Journal articles: 'TCPO'

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Steen, Jennifer A., Trudi L. Bannam, Wee Lin Teng, Rodney J. Devenish, and Julian I. Rood. "The Putative Coupling Protein TcpA Interacts with Other pCW3-Encoded Proteins To Form an Essential Part of the Conjugation Complex." Journal of Bacteriology 191, no. 9 (February 27, 2009): 2926–33. http://dx.doi.org/10.1128/jb.00032-09.

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ABSTRACT Conjugative plasmids encode antibiotic resistance determinants or toxin genes in the anaerobic pathogen Clostridium perfringens. The paradigm conjugative plasmid in this bacterium is pCW3, a 47-kb tetracycline resistance plasmid that encodes the unique tcp transfer locus. The tcp locus consists of 11 genes, intP and tcpA-tcpJ, at least three of which, tcpA, tcpF, and tcpH, are essential for the conjugative transfer of pCW3. In this study we examined protein-protein interactions involving TcpA, the putative coupling protein. Use of a bacterial two-hybrid system identified interactions between TcpA and TcpC, TcpG, and TcpH. This analysis also demonstrated TcpA, TcpC, and TcpG self-interactions, which were confirmed by chemical cross-linking studies. Examination of a series of deletion and site-directed derivatives of TcpA identified the domains and motifs required for these interactions. Based on these results, we have constructed a model for this unique conjugative transfer apparatus.

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Teng, Wee Lin, Trudi L. Bannam, Jennifer A. Parsons, and Julian I. Rood. "Functional Characterization and Localization of the TcpH Conjugation Protein from Clostridium perfringens." Journal of Bacteriology 190, no. 14 (May 16, 2008): 5075–86. http://dx.doi.org/10.1128/jb.00386-08.

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ABSTRACT In Clostridium perfringens, conjugative plasmids encode important virulence factors, such as toxins and resistance determinants. All of these plasmids carry a conjugation locus that consists of 11 genes: intP and tcpA to tcpJ. Three proteins, TcpA, a potential coupling protein, TcpF, a putative ATPase that is similar to ORF15 from Tn916, and TcpH, which contains VirB6-like domains, are essential for conjugation in the prototype conjugative plasmid pCW3. To analyze the functional domains of TcpH, a putative structural component of the mating-pair formation complex and deletion and site-directed mutants were constructed and analyzed. The results showed that the N-terminal 581 residues and the conserved 242VQQPW246 motif were required for conjugative transfer. Bacterial two-hybrid and biochemical studies showed that TcpH interacted with itself and with TcpC. An analysis of the tcpH mutants demonstrated that the region required for these interactions also was localized to the N-terminal 581 residues and that the function of the C-terminal region of TcpH was independent of protein-protein interactions. Finally, immunofluorescence studies showed that TcpH and TcpF were located at both cell poles of donor C. perfringens cells. The results provide evidence that TcpH is located in the cell membrane, where it oligomerizes and interacts with TcpC to form part of the mating-pair formation complex, which is located at the cell poles and is closely associated with TcpF.

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Wu, Daoxia, Dinghua Zhang, and Changfeng Yao. "Effect of Turning and Surface Polishing Treatments on Surface Integrity and Fatigue Performance of Nickel-Based Alloy GH4169." Metals 8, no. 7 (July 18, 2018): 549. http://dx.doi.org/10.3390/met8070549.

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In this paper, the effects of turning and surface polishing treatments on surface integrity and fatigue properties of superalloy GH4169 were investigated. Finish turning (FT), surface circumferential polishing treatment (TCP), surface oblique texture (TCPO), and surface axial texture (TCPA) were applied to GH4169 superalloy. The surface roughness, surface topography, residual stress, microhardness, and microstructure after different processes were studied. Rotating bending fatigue tests were carried out to investigate the effects of surface integrity and surface texture direction on the fatigue performance of GH4169. The experiments reveal that the TCPA specimens present the longest fatigue life of 15.01 × 104 cycles. By comparison with the FT, TCP, and TCPO specimens, the fatigue lives of TCPA specimens are increased by 134.2%, 183.7%, and 96.2%, respectively. Single crack initiation source is observed for TCPA specimen. It is mainly attributed to the small surface stress concentration factor and surface axial texture.

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Knight, Sarah L., Richard P. Taylor, Adrian A. Polliack, and Dan L. Bader. "Establishing predictive indicators for the status of loaded soft tissues." Journal of Applied Physiology 90, no. 6 (June 1, 2001): 2231–37. http://dx.doi.org/10.1152/jappl.2001.90.6.2231.

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Two complementary techniques were employed to assess the soft tissue response to applied pressure. The noninvasive methods involve the simultaneous measurement of the local tensions of oxygen and carbon dioxide (tcPo 2 and tcPco 2) and the collection and subsequent analysis of sweat collected from the sacrum, a common site for the development of pressure sores. All tests were performed on able-bodied subjects. Results have indicated that oxygen levels (tcPo 2) were lowered in soft tissues subjected to applied pressures of between 40 (5.3 kPa) and 120 mmHg (16.0 kPa). At the higher pressures, this decrease was generally associated with an increase in carbon dioxide levels (tcPco 2) well above the normal basal levels of 45 mmHg (6 kPa). There were also considerable increases, in some cases up to twofold, in the concentrations of both sweat lactate and urea at the loaded site compared with the unloaded control. By comparing selected parameters, a threshold value for loaded tcPo 2 was identified, representing a reduction of ∼60% from unloaded values. Above this threshold, there was a significant relationship between this parameter and the loaded/unloaded concentration ratios for both sweat metabolites. These parameters may prove useful in identifying those subjects whose soft tissue may be compromised during periods of pressure ischemia.

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Seinturier, Christophe, Sophie Blaise, Théophile Tiffet, Cynthia Brousseau Provencher, Jean Luc Cracowski, Gilles Pernod, and Patrick Carpentier. "Fluorescence angiography compared to toe blood pressure in the evaluation of severe limb ischemia." Vasa 49, no. 3 (April 1, 2020): 230–34. http://dx.doi.org/10.1024/0301-1526/a000853.

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Summary: Background: Severity of limb ischemia in peripheral arterial disease (PAD) patients is usually evaluated by clinical assessment and toe blood pressure (TBP) or transcutaneous oxygen pressures (TcPO 2). Indocyanin green angiography (IGA) is a promising tool generating a foot cartography of skin microvascular perfusion. However, there is no consensus about the fluorescence parameters that should be used to evaluate ischemia. The purpose of this cross-sectional evaluation and 3-month clinical follow-up was to determine the best fluorescence parameter for the evaluation of severe PAD, using TBP as reference. Patients and methods: IGA was realized in patients with clinical suspicion of CLI in addition to TBP and TcPO 2. Parameters from the time intensity fluorescence curve measured on the foot were compared with TBP (primary reference), and with TcPO2. Clinical outcomes (amputation, revascularization, death) were recorded at 3 months follow-up. Results: Thirty-four patients were included and IGA could be analysed in 29 of them. When all limbs were studied, no significant correlation was found between any of the measured fluorescence parameters (saturation time, ingress slope, amplitude, delay) and TBP pressure neither TCPO2. In the limbs with CLI, a significant correlation between the TBP and amplitude on the forefoot was found. According to the outcome, none of the fluorescence parameters showed a significant prognostic value in contrast to the significant results for TBP and TcPO2. Conclusions: In this study, quantitative analysis of IGA parameters did not show any prognostic value, nor was there any significant statistical association with well-established prognostic parameters such as TBP and TcPO 2 in patients with suspected CLI. A correlation was found between amplitude and TBP in patients with CLI. Topographical information such as perfusion heterogeneity was not evaluated and remains a valuable target to be investigated.

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Yu, Rosa R., and Victor J. DiRita. "Analysis of an Autoregulatory Loop Controlling ToxT, Cholera Toxin, and Toxin-Coregulated Pilus Production inVibrio cholerae." Journal of Bacteriology 181, no. 8 (April 15, 1999): 2584–92. http://dx.doi.org/10.1128/jb.181.8.2584-2592.1999.

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ABSTRACT Coordinate expression of many virulence genes in the human pathogenVibrio cholerae is controlled by the ToxR, TcpP, and ToxT proteins. These proteins function in a regulatory cascade in which ToxR and TcpP, two inner membrane proteins, are required to activatetoxT and ToxT is the direct activator of virulence gene expression. ToxT-activated genes include those whose products are required for the biogenesis of cholera toxin (CTX) and the toxin-coregulated pilus, the major subunit of which is TcpA. This work examined control of toxT transcription. We tested a model whereby activation of toxT by ToxR and TcpP is required to prime an autoregulatory loop in which ToxT-dependent transcription of the tcpA promoter reads through a proposed terminator between the tcpF and toxT genes to result in continued ToxT production. Primer extension analysis of RNA from wild-type classical strain O395 showed that there are two products encoding toxT, one of which is longer than the other by 105 bp. Deletion of the toxT promoter (toxTΔpro ) resulted in the abolishment oftoxT transcription, as predicted. Deletion of thetcpA promoter (tcpAΔpro ) had no effect on subsequent detection of the smaller toxT primer extension product, but the larger toxT product was not detected, indicating that this product may be the result of transcription from the tcpA promoter and not of initiation directly upstream of toxT. Neither mutant strain produced detectable TcpA, but the CTX levels of the strains were different. ThetoxTΔpro strain produced little detectable CTX, while the tcpAΔpro strain produced CTX levels intermediate between those of the wild-type andtoxTΔpro strains. Dependence oftoxT transcription on TcpP and TcpH was confirmed by analyzing RNAs from strains carrying deletions in the genes encoding these regulators. The tcpP defect resulted in undetectabletoxT transcription, whereas the tcpH mutation led to a diminishing of toxT RNA but not complete abolishment. Taken together, these results suggest thattoxT transcription is dependent on two different promoters; one is directly upstream and is activated in part by TcpP and TcpH, and the other is much further upstream and is activated by ToxT.

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Wisniewski, Jessica A., Wee L. Teng, Trudi L. Bannam, and Julian I. Rood. "Two Novel Membrane Proteins, TcpD and TcpE, Are Essential for Conjugative Transfer of pCW3 in Clostridium perfringens." Journal of Bacteriology 197, no. 4 (December 8, 2014): 774–81. http://dx.doi.org/10.1128/jb.02466-14.

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The anaerobic pathogenClostridium perfringensencodes either toxin genes or antibiotic resistance determinants on a unique family of conjugative plasmids that have a novel conjugation region, thetcplocus. Studies of the paradigm conjugative plasmid fromC. perfringens, the 47-kb tetracycline resistance plasmid pCW3, have identified severaltcp-encoded proteins that are involved in conjugative transfer and form part of the transfer apparatus. In this study, the role of the conserved hypothetical proteins TcpD, TcpE, and TcpJ was examined. Mutation and complementation analyses showed that TcpD and TcpE were essential for the conjugative transfer of pCW3, whereas TcpJ was not required. To analyze the TcpD and TcpE proteins inC. perfringens, functional hemagglutinin (HA)-tagged derivatives were constructed. Western blots showed that TcpD and TcpE localized to the cell envelope fraction independently of the presence of other pCW3-encoded proteins. Finally, examination of the subcellular localization of TcpD and TcpE by immunofluorescence showed that these proteins were concentrated at both poles ofC. perfringensdonor cells, where they are postulated to form essential components of the multiprotein complex that comprises the transfer apparatus.

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White, Augustus M., Deborah J. Ossip, L. Morgan Snell, Dongmei Li, Cosima Hoetger, Richard O'Connor, Rebecca C. Lester, et al. "Tobacco Product Access Scenarios Influence Hypothetical Use Behaviors." Tobacco Regulatory Science 7, no. 3 (May 1, 2021): 184–202. http://dx.doi.org/10.18001/trs.7.3.4.

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Objective: In this paper, we characterize how potential policies restricting access to tobacco products may impact use behaviors among adult, past 30-day, smokers and e-cigarette users. Methods: We conducted an online experiment with 820 smokers, e-cigarette users, and dual users (April 27-June 8, 2020). We randomized participants to one of 4 hypothetical access scenarios: (1) tobacco retail stores open + pharmacies open (TOPO); (2) tobacco stores open but favorite brand unavailable + pharmacies open (TOPO-NFB); (3) tobacco stores closed + pharmacies open (TCPO); and (4) tobacco stores closed + pharmacies closed (TCPC). Outcomes (measured on 0-100 visual analog scales) included the likelihood of quitting, reducing, switching brands or products, and finding another source of tobacco products. Seemingly unrelated regressions tested for associations between access scenarios and prospective tobacco use behaviors. Results: Participants in the TCPO and TOPO-NFB scenarios were more likely to reduce use, switch brands/products, and find another source (ps < .001) than those in the TOPO scenario. Dual and flavored product users were more likely to switch products (ps < .01). Conclusions: When tobacco retailers are closed, tobacco users may be more likely to quit and/or reduce use compared to when retailers are open. However, access restrictions could prompt users to switch tobacco brands/products or sources.

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Louie, Tai Man, Christopher M. Webster, and Luying Xun. "Genetic and Biochemical Characterization of a 2,4,6-Trichlorophenol Degradation Pathway in Ralstonia eutropha JMP134." Journal of Bacteriology 184, no. 13 (July 1, 2002): 3492–500. http://dx.doi.org/10.1128/jb.184.13.3492-3500.2002.

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ABSTRACT Ralstonia eutropha JMP134 can grow on several chlorinated aromatic pollutants, including 2,4-dichlorophenoxyacetate and 2,4,6-trichlorophenol (2,4,6-TCP). Although a 2,4,6-TCP degradation pathway in JMP134 has been proposed, the enzymes and genes responsible for 2,4,6-TCP degradation have not been characterized. In this study, we found that 2,4,6-TCP degradation by JMP134 was inducible by 2,4,6-TCP and subject to catabolic repression by glutamate. We detected 2,4,6-TCP-degrading activities in JMP134 cell extracts. Our partial purification and initial characterization of the enzyme indicated that a reduced flavin adenine dinucleotide (FADH2)-utilizing monooxygenase converted 2,4,6-TCP to 6-chlorohydroxyquinol (6-CHQ). The finding directed us to PCR amplify a 3.2-kb fragment containing a gene cluster (tcpABC) from JMP134 by using primers designed from conserved regions of FADH2-utilizing monooxygenases and hydroxyquinol 1,2-dioxygenases. Sequence analysis indicated that tcpA, tcpB, and tcpC encoded an FADH2-utilizing monooxygenase, a probable flavin reductase, and a 6-CHQ 1,2-dioxygenase, respectively. The three genes were individually inactivated in JMP134. The tcpA mutant failed to degrade 2,4,6-TCP, while both tcpB and tcpC mutants degraded 2,4,6-TCP to an oxidized product of 6-CHQ. Insertional inactivation of tcpB may have led to a polar effect on downstream tcpC, and this probably resulted in the accumulation of the oxidized form of 6-CHQ. For further characterization, TcpA was produced, purified, and shown to transform 2,4,6-TCP to 6-CHQ when FADH2 was supplied by an Escherichia coli flavin reductase. TcpC produced in E. coli oxidized 6-CHQ to 2-chloromaleylacetate. Thus, our data suggest that JMP134 transforms 2,4,6-TCP to 2-chloromaleylacetate by TcpA and TcpC. Sequence analysis suggests that tcpB may function as an FAD reductase, but experimental data did not support this hypothesis. The function of TcpB remains unknown.

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Sánchez, M. A., and B. González. "Genetic Characterization of 2,4,6-Trichlorophenol Degradation in Cupriavidus necator JMP134." Applied and Environmental Microbiology 73, no. 9 (February 23, 2007): 2769–76. http://dx.doi.org/10.1128/aem.02584-06.

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ABSTRACT The degradation pathway of 2,4,6-trichlorophenol (2,4,6-TCP), a hazardous pollutant, in the aerobic bacterium Cupriavidus necator JMP134(pJP4) (formerly Ralstonia eutropha JMP134) is encoded by the tcp genes. These genes are located in a genetic context, tcpRXABCYD, which resembles a putative catabolic operon. In this work, these gene sequences were individually disrupted and mutant strains were evaluated for their ability to grow on or degrade 2,4,6-TCP. The tcpX and tcpA mutants completely failed to degrade this compound. Although the tcpC mutant was also unable to grow on 2,4,6-TCP, it still transformed this chlorophenol to 6-chlorohydroquinol. In contrast, the tcpD mutant grew on 2,4,6-TCP, suggesting the presence of additional maleylacetate reductase-encoding genes. Five other open reading frames encoding maleylacetate reductases, in addition to the tcpD gene, were found in the genome of C. necator, and two of them provide this function in the tcpD mutant. The tcpR gene, encoding a putative LysR-type transcriptional regulator, was disrupted, and this mutant strain completely failed to grow on 2,4,6-TCP. Transcriptional fusion studies demonstrated that TcpR activates the expression of the tcp genes, responding specifically to 2,4,6-TCP. The transcriptional start of the tcp operon was mapped, and a putative σ70-type promoter was identified.

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Bose, Niranjan, and Ronald K. Taylor. "Identification of a TcpC-TcpQ Outer Membrane Complex Involved in the Biogenesis of the Toxin-Coregulated Pilus of Vibrio cholerae." Journal of Bacteriology 187, no. 7 (April 1, 2005): 2225–32. http://dx.doi.org/10.1128/jb.187.7.2225-2232.2005.

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ABSTRACT The toxin-coregulated pilus (TCP) of Vibrio cholerae and the soluble TcpF protein that is secreted via the TCP biogenesis apparatus are essential for intestinal colonization. The TCP biogenesis apparatus is composed of at least nine proteins but is largely uncharacterized. TcpC is an outer membrane lipoprotein required for TCP biogenesis that is a member of the secretin protein superfamily. In the present study, analysis of TcpC in a series of strains deficient in each of the TCP biogenesis proteins revealed that TcpC was absent specifically in a tcpQ mutant. TcpQ is a predicted periplasmic protein required for TCP biogenesis. Fractionation studies revealed that the protein is not localized to the periplasm but is associated predominantly with the outer membrane fraction. An analysis of the amount of TcpQ present in the series of tcp mutants demonstrated the inverse of the TcpC result (absence of TcpQ in a tcpC deletion strain). Complementation of the tcpQ deletion restored TcpC levels and TCP formation, and similarly, complementation of tcpC restored TcpQ. Metal affinity pull-down experiments performed using His-tagged TcpC or TcpQ demonstrated a direct interaction between TcpC and TcpQ. In the presence of TcpQ, TcpC was found to form a high-molecular-weight complex that is stable in 2% sodium dodecyl sulfate and at temperatures below 65°C, a characteristic of secretin complexes. Fractionation studies in which TcpC was overexpressed in the absence of TcpQ showed that TcpQ is also required for proper localization of TcpC to the outer membrane.

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Zhou, J., X. G. Zhou, J. W. Wang, H. Zhou, and J. Dong. "Treatment of osteomyelitis defects by a vancomycin-loaded gelatin/β-tricalcium phosphate composite scaffold." Bone & Joint Research 7, no. 1 (January 2018): 46–57. http://dx.doi.org/10.1302/2046-3758.71.bjr-2017-0129.r2.

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Objective In the present study, we aimed to assess whether gelatin/β-tricalcium phosphate (β-TCP) composite porous scaffolds could be used as a local controlled release system for vancomycin. We also investigated the efficiency of the scaffolds in eliminating infections and repairing osteomyelitis defects in rabbits. Methods The gelatin scaffolds containing differing amounts of of β-TCP (0%, 10%, 30% and 50%) were prepared for controlled release of vancomycin and were labelled G-TCP0, G-TCP1, G-TCP3 and G-TCP5, respectively. The Kirby-Bauer method was used to examine the release profile. Chronic osteomyelitis models of rabbits were established. After thorough debridement, the osteomyelitis defects were implanted with the scaffolds. Radiographs and histological examinations were carried out to investigate the efficiency of eliminating infections and repairing bone defects. Results The prepared gelatin/β-TCP scaffolds exhibited a homogeneously interconnected 3D porous structure. The G-TCP0 scaffold exhibited the longest duration of vancomycin release with a release duration of eight weeks. With the increase of β-TCP contents, the release duration of the β-TCP-containing composite scaffolds was decreased. The complete release of vancomycin from the G-TCP5 scaffold was achieved within three weeks. In the treatment of osteomyelitis defects in rabbits, the G-TCP3 scaffold showed the most efficacious performance in eliminating infections and repairing bone defects. Conclusions The composite scaffolds could achieve local therapeutic drug levels over an extended duration. The G-TCP3 scaffold possessed the optimal porosity, interconnection and controlled release performance. Therefore, this scaffold could potentially be used in the treatment of chronic osteomyelitis defects. Cite this article: J. Zhou, X. G. Zhou, J. W. Wang, H. Zhou, J. Dong. Treatment of osteomyelitis defects by a vancomycin-loaded gelatin/β-tricalcium phosphate composite scaffold. Bone Joint Res 2018;7:46–57. DOI: 10.1302/2046-3758.71.BJR-2017-0129.R2.

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BECKER, F., J. BECKER, B. TERRIAT, E. STEINMETZ, and M. DAVID. "Evaluation of lower limb ischemia using TCPO." Biorheology 32, no. 2-3 (March 1995): 146. http://dx.doi.org/10.1016/0006-355x(95)92007-w.

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Coleman, L. S., G. S. E. Dowd, and G. Bentley. "Reproducibility of tcPO 2 measurements in normal volunteers." Clinical Physics and Physiological Measurement 7, no. 3 (August 1986): 259–63. http://dx.doi.org/10.1088/0143-0815/7/3/006.

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Sarkar, Amit, Ranjan K. Nandy, G. Balakrish Nair, and Asoke C. Ghose. "Vibrio Pathogenicity Island and Cholera Toxin Genetic Element-Associated Virulence Genes and Their Expression in Non-O1 Non-O139 Strains of Vibrio cholerae." Infection and Immunity 70, no. 8 (August 2002): 4735–42. http://dx.doi.org/10.1128/iai.70.8.4735-4742.2002.

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ABSTRACT A non-O1 non-O139 Vibrio cholerae strain, 10259, belonging to the serogroup O53 was shown to harbor genes related to the vibrio pathogenicity island (VPI) and a cholera toxin (CT) genetic element called CTX. While the nucleotide sequence of the strain 10259 tcpA gene differed significantly (26 and 28%) from those of O1 classical and El Tor biotype strains, respectively, partial sequence analysis data of certain other VPI-associated genes (aldA, tagA, tcpP/H, toxT, acfB/C, and int) and intergenic regions (tcpF to toxT and tcpH to tcpA) of the strain showed only minor variations (0.4 to 4.8%) from corresponding sequences in O1 strains. Strain 10259 also contained CTX element-associated toxin genes with sequences almost identical to those of O1 strains. Growth of the organism in Luria broth (LB) under ToxR inducing conditions (30°C and pH 6.5) led to transcriptional activation of tcpP/H, toxR, toxT, and tcpA genes, but not of ctxA, as determined by reverse transcription-PCR (RT-PCR). Subsequent analysis revealed that strain 10259 possessed only two copies (instead of three or more copies found in epidemic-causing O1 or O139 strains) of the heptanucleotide (TTTTGAT) repeats in the intergenic region upstream of ctxAB. Therefore, a strain 10259 mutant was generated by replacement of this region with a homologous region (1.4 kb) derived from a V. cholerae O1 classical biotype strain (O395) that contained seven such repeats. The resultant recombinant strain (10259R) was found to be capable of coordinately regulated expression of toxT, ctxA, and tcpA when grown under the ToxR inducing conditions. Serological studies also demonstrated that the recombinant strain produced TcpA and a significantly (∼1,000-fold) higher level of CT in vitro compared to that of the parent strain. Virulence gene expression in two other non-O1 non-O139 strains (serogroup O37) containing VPI and the CTX element was studied by RT-PCR and serological assay. One strain (S7, which was involved in an epidemic in Sudan in 1968) showed coordinately regulated expression of virulence genes leading to the production of both CT and TcpA in LB medium. However, the other strain, V2, produced RT-PCR-detectable transcripts of toxT, ctxA, or tcpA genes in the early phase (6 h), but not in the late phase (16 h) of growth in LB medium. These results are consistent with the low levels of production of CT and TcpA by the strain that were serologically detectable. The significance of these results is discussed in relation to the role of virulence genes and their expression to the pathogenic potential of V. cholerae strains belonging to non-O1 serogroups.

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Kelechi, Teresa J., and Yvonne Michel. "A Descriptive Study of Skin Temperature, Tissue Perfusion, and Tissue Oxygen in Patients With Chronic Venous Disease." Biological Research For Nursing 9, no. 1 (July 2007): 70–80. http://dx.doi.org/10.1177/1099800407299424.

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Chronic inflammation and microcirculatory disturbances of the skin have been implicated as causative factors of complications associated with chronic venous disease (CVD). The purpose of this study is to describe the mean differences between and correlations among three measures of microcirculation: skin temperature (Tsk), tissue perfusion/blood flow (BF), and tissue oxygen (tcPO2) of CVD-inflamed skin compared to normal controls. In a convenience sample of 55 patients with CVD ( n = 31) and without CVD ( n = 24), Tsk was measured with an infrared thermometer, BF with a laser Doppler flowmeter, and tcPO 2 with a transcutaneous oximeter across three measurements periods 1 week apart (Times 1, 2, and 3) at the medial aspect of both lower legs. Tsk was higher (1.2°C) across all measurement periods ( p < .05), BF was higher at Times 1 and 3 ( p = .002 and .012, respectively), and tcPO2 was lower at Times 1 and 3 ( p = .013 and .050, respectively) in the CVD group as compared to the non-CVD group. BF and Tsk were positively correlated at Times 1 and 2 ( r = .516, p < .005; r = 0.278, p = .04) but not at Time 3 ( r = 0.235, p > .05). No consistently significant correlations were found between tcPO2 and BF or tcPO2 and Tsk ( p > .05). Tsk and BF were higher in the skin of lower legs affected by CVD than in those not affected. Pathological processes in the skin produce heat detectable by an infrared thermometer. Measurement and monitoring of Tsk can augment clinical findings and guide treatment when localized inflammation is suspected. Future studies of Tsk should be directed toward the usefulness of infrared technology to develop a CVD leg ulcer prediction model.

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Morgan, Sarah J., Emily L. French, Joshua J. Thomson, Craig P. Seaborn, Christian A. Shively, and Eric S. Krukonis. "Formation of an Intramolecular Periplasmic Disulfide Bond in TcpP Protects TcpP and TcpH from Degradation in Vibrio cholerae." Journal of Bacteriology 198, no. 3 (November 16, 2015): 498–509. http://dx.doi.org/10.1128/jb.00338-15.

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ABSTRACTTcpP and ToxR coordinately regulate transcription oftoxT, the master regulator of numerous virulence factors inVibrio cholerae. TcpP and ToxR are membrane-localized transcription factors, each with a periplasmic domain containing two cysteines. In ToxR, these cysteines form an intramolecular disulfide bond and a cysteine-to-serine substitution affects activity. We determined that the two periplasmic cysteines of TcpP also form an intramolecular disulfide bond. Disruption of this intramolecular disulfide bond by mutation of either cysteine resulted in formation of intermolecular disulfide bonds. Furthermore, disruption of the intramolecular disulfide bond in TcpP decreased the stability of TcpP. While the decreased stability of TcpP-C207S resulted in a nearly complete loss oftoxTactivation and cholera toxin (CT) production, the second cysteine mutant, TcpP-C218S, was partially resistant to proteolytic degradation and maintained ∼50%toxTactivation capacity. TcpP-C218S was also TcpH independent, since deletion oftcpHdid not affect the stability of TcpP-C218S, whereas wild-type TcpP was degraded in the absence of TcpH. Finally, TcpH was also unstable when intramolecular disulfides could not be formed in TcpP, suggesting that the single periplasmic cysteine in TcpH may assist with disulfide bond formation in TcpP by interacting with the periplasmic cysteines of TcpP. Consistent with this finding, a TcpH-C114S mutant was unable to stabilize TcpP and was itself unstable. Our findings demonstrate a periplasmic disulfide bond in TcpP is critical for TcpP stability and virulence gene expression.IMPORTANCETheVibrio choleraetranscription factor TcpP, in conjunction with ToxR, regulates transcription oftoxT, the master regulator of numerous virulence factors inVibrio cholerae. TcpP is a membrane-localized transcription factor with a periplasmic domain containing two cysteines. We determined that the two periplasmic cysteines of TcpP form an intramolecular disulfide bond and disruption of the intramolecular disulfide bond in TcpP decreased the stability of TcpP and reduced virulence gene expression. Normally TcpH, another membrane-localized periplasmic protein, protects TcpP from degradation. However, we found that TcpH was also unstable when intramolecular disulfides could not be formed in TcpP, indicating that the periplasmic cysteines of TcpP are required for functional interaction with TcpH and that this interaction is required for both TcpP and TcpH stability.

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Tripathi, Shital A., and Ronald K. Taylor. "Membrane Association and Multimerization of TcpT, the Cognate ATPase Ortholog of the Vibrio cholerae Toxin-Coregulated-Pilus Biogenesis Apparatus." Journal of Bacteriology 189, no. 12 (April 13, 2007): 4401–9. http://dx.doi.org/10.1128/jb.00008-07.

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ABSTRACT The toxin-coregulated pilus (TCP) is one of the major virulence factors of Vibrio cholerae. Biogenesis of this type 4 pilus (Tfp) requires a number of structural components encoded by the tcp operon. TcpT, the cognate putative ATPase, is required for TCP biogenesis and all TCP-mediated functions. We studied the stability and localization of TcpT in cells containing in-frame deletions in each of the tcp genes. TcpT was detectable in each of the biogenesis mutants except the ΔtcpT strain. TcpT was localized to the inner membrane (IM) in a TcpR-dependent manner. TcpR is a predicted bitopic inner membrane protein of the TCP biogenesis apparatus. Using metal affinity pull-down experiments, we demonstrated interaction between TcpT and TcpR. Using Escherichia coli as a heterologous system, we investigated direct interaction between TcpR and TcpT. We report that TcpR is sufficient for TcpT IM localization per se; however, stable IM localization of TcpT requires an additional V. cholerae-specific factor(s). A LexA-based two-hybrid system was utilized to define interaction domains of the two proteins. We demonstrate a strong interaction between the cytoplasmic domain of TcpR and the N-terminal 100 amino acid residues of TcpT. We also demonstrated the ability of the C-terminal domain of TcpT to multimerize.

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Chaichi, M. J., M. Ehsani, S. Asghari, and V. Behboodi. "Determination of vitamin B6using an optimized novel TCPO-indolizine-H2O2chemiluminescence system." Luminescence 29, no. 8 (June 27, 2014): 1169–76. http://dx.doi.org/10.1002/bio.2678.

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Belchik, Sara Mae, and Luying Xun. "Functions of Flavin Reductase and Quinone Reductase in 2,4,6-Trichlorophenol Degradation by Cupriavidus necator JMP134." Journal of Bacteriology 190, no. 5 (December 28, 2007): 1615–19. http://dx.doi.org/10.1128/jb.01697-07.

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ABSTRACT The tcpRXABCYD operon of Cupriavidus necator JMP134 is involved in the degradation of 2,4,6-trichlorophenol (2,4,6-TCP), a toxic pollutant. TcpA is a reduced flavin adenine dinucleotide (FADH2)-dependent monooxygenase that converts 2,4,6-TCP to 6-chlorohydroxyquinone. It has been implied via genetic analysis that TcpX acts as an FAD reductase to supply TcpA with FADH2, whereas the function of TcpB in 2,4,6-TCP degradation is still unclear. In order to provide direct biochemical evidence for the functions of TcpX and TcpB, the two corresponding genes (tcpX and tcpB) were cloned, overexpressed, and purified in Escherichia coli. TcpX was purified as a C-terminal His tag fusion (TcpXH) and found to possess NADH:flavin oxidoreductase activity capable of reducing either FAD or flavin mononucleotide (FMN) with NADH as the reductant. TcpXH had no activity toward NADPH or riboflavin. Coupling of TcpXH and TcpA demonstrated that TcpXH provided FADH2 for TcpA catalysis. Among several substrates tested, TcpB showed the best activity for quinone reduction, with FMN or FAD as the cofactor and NADH as the reductant. TcpB could not replace TcpXH in a coupled assay with TcpA for 2,4,6-TCP metabolism, but TcpB could enhance TcpA activity. Further, we showed that TcpB was more effective in reducing 6-chlorohydroxyquinone than chemical reduction alone, using a thiol conjugation assay to probe transitory accumulation of the quinone. Thus, TcpB was acting as a quinone reductase for 6-chlorohydroxyquinone reduction during 2,4,6-TCP degradation.

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Mouren, X., Ph Caillard, M. Massonneau, and B. Thébault. "TcPO 2 Measurement Reproducibility During Stress in Stage II Obliterative Arterial Disease." Angiology 47, no. 4 (April 1996): 329–36. http://dx.doi.org/10.1177/000331979604700402.

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Beck, Nancy A., Eric S. Krukonis, and Victor J. DiRita. "TcpH Influences Virulence Gene Expression in Vibrio cholerae by Inhibiting Degradation of the Transcription Activator TcpP." Journal of Bacteriology 186, no. 24 (December 15, 2004): 8309–16. http://dx.doi.org/10.1128/jb.186.24.8309-8316.2004.

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ABSTRACT Expression of toxT, the transcription activator of cholera toxin and pilus production in Vibrio cholerae, is the consequence of a complex cascade of regulatory events that culminates in activation of the toxT promoter by TcpP and ToxR, two membrane-localized transcription factors. Both are encoded in operons with genes whose products, TcpH and ToxS, which are also membrane localized, are hypothesized to control their activity. In this study we analyzed the role of TcpH in controlling TcpP function. We show that a mutant of V. cholerae lacking TcpH expressed virtually undetectable levels of TcpP, although tcpP mRNA levels remain unaffected. A time course experiment showed that levels of TcpP, expressed from a plasmid, are dramatically reduced over time without co-overexpression of TcpH. By contrast, deletion of toxS did not affect ToxR protein levels. A fusion protein in which the TcpP periplasmic domain is replaced with that of ToxR remains stable, suggesting that the periplasmic domain of TcpP is the target for degradation of the protein. Placement of the periplasmic domain of TcpP on ToxR, an otherwise stable protein, results in instability, providing further evidence for the hypothesis that the periplasmic domain of TcpP is a target for degradation. Consistent with this interpretation is our finding that derivatives of TcpP lacking a periplasmic domain are more stable in V. cholerae than are derivatives in which the periplasmic domain has been truncated. This work identifies at least one role for the periplasmic domain of TcpP, i.e., to act as a target for a protein degradation pathway that regulates TcpP levels. It also provides a rationale for why the V. cholerae tcpH mutant strain is avirulent. We hypothesize that regulator degradation may be an important mechanism for regulating virulence gene expression in V. cholerae.

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Wang, Lijuan, and Yuhai Tang. "Determination of dipyridamole using TCPO-H2O2 chemiluminescence in the presence of silver nanoparticles." Luminescence 26, no. 6 (April 19, 2011): 703–9. http://dx.doi.org/10.1002/bio.1301.

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Murley, Yvette M., Patricia A. Carroll, Karen Skorupski, Ronald K. Taylor, and Stephen B. Calderwood. "Differential Transcription of the tcpPHOperon Confers Biotype-Specific Control of the Vibrio cholerae ToxR Virulence Regulon." Infection and Immunity 67, no. 10 (October 1, 1999): 5117–23. http://dx.doi.org/10.1128/iai.67.10.5117-5123.1999.

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ABSTRACT Epidemic strains of Vibrio cholerae O1 are divided into two biotypes, classical and El Tor. In both biotypes, regulation of virulence gene expression depends on a cascade in which ToxR activates expression of ToxT, and ToxT activates expression of cholera toxin and other virulence genes. In the classical biotype, maximal expression of this ToxR regulon in vitro occurs at 30°C at pH 6.5 (ToxR-inducing conditions), whereas in the El Tor biotype, production of these virulence genes only occurs under very limited conditions and not in response to temperature and pH; this difference between biotypes is mediated at the level of toxT transcription. In the classical biotype, two other proteins, TcpP and TcpH, are needed for maximal toxT transcription. Transcription oftcpPH in the classical biotype is regulated by pH and temperature independently of ToxR or ToxT, suggesting that TcpP and TcpH couple environmental signals to transcription of toxT. In this study, we show a near absence of tcpPH message in the El Tor biotype under ToxR-inducing conditions of temperature and pH. However, once expressed, El Tor TcpP and TcpH appear to be as effective as classical TcpP and TcpH in activating toxTtranscription. These results suggest that differences in regulation of virulence gene expression between the biotypes of V. cholerae primarily result from differences in expression oftcpPH message in response to environmental signals. We present an updated model for control of the ToxR virulence regulon inV. cholerae.

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Parsons, Jennifer A., Trudi L. Bannam, Rodney J. Devenish, and Julian I. Rood. "TcpA, an FtsK/SpoIIIE Homolog, Is Essential for Transfer of the Conjugative Plasmid pCW3 in Clostridium perfringens." Journal of Bacteriology 189, no. 21 (August 24, 2007): 7782–90. http://dx.doi.org/10.1128/jb.00783-07.

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ABSTRACT The conjugative tetracycline resistance plasmid pCW3 is the paradigm conjugative plasmid in the anaerobic gram-positive pathogen Clostridium perfringens. Two closely related FtsK/SpoIIIE homologs, TcpA and TcpB, are encoded on pCW3, which is significant since FtsK domains are found in coupling proteins of gram-negative conjugation systems. To develop an understanding of the mechanism of conjugative transfer in C. perfringens, we determined the role of these proteins in the conjugation process. Mutation and complementation analysis was used to show that the tcpA gene was essential for the conjugative transfer of pCW3 and that the tcpB gene was not required for transfer. Furthermore, complementation of a pCW3ΔtcpA mutant with divergent tcpA homologs provided experimental evidence that all of the known conjugative plasmids from C. perfringens use a similar transfer mechanism. Functional genetic analysis of the TcpA protein established the essential role in conjugative transfer of its Walker A and Walker B ATP-binding motifs and its FtsK-like RAAG motif. It is postulated that TcpA is the essential DNA translocase or coupling protein encoded by pCW3 and as such represents a key component of the unique conjugation process in C. perfringens.

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Dantoni, Patrícia, Ana Clara B. Rodrigues, Margareth Mie N. Matsuda, and Nina Coichev. "Effect of some surfactants on the chemiluminescent reactions of bis(2,4,6-trichlorophenyl)oxalate and bis(2-nitrophenyl)oxalate with hydrogen peroxide." Canadian Journal of Chemistry 90, no. 6 (June 2012): 534–41. http://dx.doi.org/10.1139/v2012-025.

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The chemiluminescent reactions of bis(2,4,6-trichlorophenyl)oxalate (TCPO) and bis(2-nitrophenyl)oxalate (2-NPO) with hydrogen peroxide in acetonitrile/water micellar systems (anionic, cationic, and non-ionic) and γ-cyclodextrin were studied in the presence of fluoranthene or 9,10-diphenylanthracene, imidazole, and two buffer solutions, HTRIS+/TRIS and H2PO4–/HPO42–. The relative chemiluminenscence (CL) intensity is higher in the presence of the cationic (DDAB, CTAC, DODAC, and OTAC), anionic (SDS), and non-ionic (Tween 80) surfactants. In the presence of some non-ionic surfactants (Brij 35, Brij 76, and Tween 20), the CL intensity was partially quenched compared with the reaction with no surfactant. The sensitivity for hydrogen peroxide determination in the range 0.01 × 10−4 to 1.0 × 10−4 mol L–1, considering the slope of the calibration curves (maximum peak height of CL vs. concentration), improved with the introduction of DDAH, CTAB, and SDS in HTRIS+/TRIS buffer.

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Cheldyshova, N. B., A. A. Kritskiy, Ya M. Krasnov, and N. I. Smirnova. "Analysis of the fragmented and full genome sequencing of atypical Vibrio Cholerae strains of the classical biovar, which brought about to the outbreak of the Asian cholera in Russia." Epidemiology and Infectious Diseases 20, no. 5 (October 15, 2015): 24–31. http://dx.doi.org/10.17816/eid40948.

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The aim of the research was the study of genetic changes in the genome of classical strains of Vibrio Cholerae which brought about to the atypical outbreak of Asian cholera in Russia in 1942 - 1943. Genome-wide and fragmented sequencing of mentioned strains revealed the presence of mutations in their structural (tcpC, tcpF, tcpS, purE) and regulatory (vieA, vieS, toxR, hapR, rpoS, crp) genes. The overproduction of CT and TCP, as well as the lack of production NAR were found to be caused by mutations in regulatory genes (hapR and rpoS). Adenine auxotrophy in V. cholerae strain M-29 is associated with a mutation in a gene purE. Thus, atypicality of the epidemic and clinical processes in the outbreak of cholera in Russia in 1942 - 1943 was associated with a combination of phenotypic features (auxotrophy, overproduction CT, TCP, lack of product HAP) of strains which brought it, caused by mutations in the structural (purE) and regulatory (hapR and rpoS) genes with social factors (war, starvation, weakened body of prisoners).

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Aruhomukama, Dickson, Ivan Sserwadda, and Gerald Mboowa. "Whole-genome sequence analysis of Vibrio cholerae from three outbreaks in Uganda, 2014 - 2016." F1000Research 8 (August 2, 2019): 1340. http://dx.doi.org/10.12688/f1000research.20048.1.

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Background: Cholera remains a serious public health problem in Uganda and Africa. The aim of this study was to provide the complete array of antimicrobial resistance genes, integrative and conjugative elements, virulence genes, pathogenicity islands, plasmids, and insertion sequences in the strains. In addition, this study also aimed to provide a single nucleotide polymorphism (SNP) based phylogenetic analysis of the strains. Methods: In the analysis, both Linux and web-based bioinformatics approaches were used to analyze the study sequences. Databases used included; FastQC, MultiQC, Snippy, PANTHER, PATRIC, Unicycler, ISFinder, Center for Genomic Epidemiology pipelines (i.e. MLST, PlasmidFinder, MyDbFinder, and ResFinder), MashTree and IcyTree. Results: The 10 sequenced strains of Vibrio cholerae were found to carry virulence-associated genes including MakA, ctxA, ctxB, carA, carB, trpB, clpB, ace, toxR, zot, rtxA, ompW, ompR, gmhA, fur, hlyA, and rstR. Also identified were: genes of the Type VI secretion system including vasA-L, vgrG-2, vgrG-3, vipA/mglA, and vipB/mglB; alsD (VC1589), involved in the synthesis of 2,3-butanediol; alsR, involved in the acetate-responsive LysR-type regulation; makA, the flagella-mediated cytotoxin gene; Type VI pilus genes including tcpA-F, tcpH-J, tcpN, tcpP-T, and icmF/vasK; adherence genes acfA-D and IlpA; and quorum sensing system genes luxS and cqsA. Pathogenicity islands identified comprised of VSP-1 and VSP-2, as well as VPI-1 and VPI-2. In addition, strA and B, APH(3'')-I, APH(3'')-Ib, APH(6)-Id, APH(6)-Ic, murA, pare, dfrA1, floR, catB, and catB9 were among the antimicrobial resistance genes found in the sequences. Analysis for SNPs shared among the sequences showed that the sequenced strains shared 218 SNPs and of these, 98 SNPs were missense. Gene enrichment analysis of these SNPs showed enrichment in genes that mediate transmembrane-signaling receptor activity, peptidyl-prolyl cis-trans isomerase activity, and phosphor-relay response regulator activity. Conclusions: This study applied bioinformatics approaches to provide comprehensive genomic analysis of V. cholerae genomes obtained from Uganda.

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Zhang, Leifeng, Changle Li, Yilun Fan, Xuehe Zhang, and Jie Zhao. "Physician-Friendly Tool Center Point Calibration Method for Robot-Assisted Puncture Surgery." Sensors 21, no. 2 (January 7, 2021): 366. http://dx.doi.org/10.3390/s21020366.

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After each robot end tool replacement, tool center point (TCP) calibration must be performed to achieve precise control of the end tool. This process is also essential for robot-assisted puncture surgery. The purpose of this article is to solve the problems of poor accuracy stability and strong operational dependence in traditional TCP calibration methods and to propose a TCP calibration method that is more suitable for a physician. This paper designs a special binocular vision system and proposes a vision-based TCP calibration algorithm that simultaneously identifies tool center point position (TCPP) and tool center point frame (TCPF). An accuracy test experiment proves that the designed special binocular system has a positioning accuracy of ±0.05 mm. Experimental research shows that the magnitude of the robot configuration set is a key factor affecting the accuracy of TCPP. Accuracy of TCPF is not sensitive to the robot configuration set. Comparison experiments show that the proposed TCP calibration method reduces the time consumption by 82%, improves the accuracy of TCPP by 65% and improves the accuracy of TCPF by 52% compared to the traditional method. Therefore, the method proposed in this article has higher accuracy, better stability, less time consumption and less dependence on the operations than traditional methods, which has a positive effect on the clinical application of high-precision robot-assisted puncture surgery.

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Zhang, Leifeng, Changle Li, Yilun Fan, Xuehe Zhang, and Jie Zhao. "Physician-Friendly Tool Center Point Calibration Method for Robot-Assisted Puncture Surgery." Sensors 21, no. 2 (January 7, 2021): 366. http://dx.doi.org/10.3390/s21020366.

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After each robot end tool replacement, tool center point (TCP) calibration must be performed to achieve precise control of the end tool. This process is also essential for robot-assisted puncture surgery. The purpose of this article is to solve the problems of poor accuracy stability and strong operational dependence in traditional TCP calibration methods and to propose a TCP calibration method that is more suitable for a physician. This paper designs a special binocular vision system and proposes a vision-based TCP calibration algorithm that simultaneously identifies tool center point position (TCPP) and tool center point frame (TCPF). An accuracy test experiment proves that the designed special binocular system has a positioning accuracy of ±0.05 mm. Experimental research shows that the magnitude of the robot configuration set is a key factor affecting the accuracy of TCPP. Accuracy of TCPF is not sensitive to the robot configuration set. Comparison experiments show that the proposed TCP calibration method reduces the time consumption by 82%, improves the accuracy of TCPP by 65% and improves the accuracy of TCPF by 52% compared to the traditional method. Therefore, the method proposed in this article has higher accuracy, better stability, less time consumption and less dependence on the operations than traditional methods, which has a positive effect on the clinical application of high-precision robot-assisted puncture surgery.

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Baig, Noorullah, Suchetha Shetty, Moustafa Sherief Moustafa, Saleh Al-Mousawi, and Bassam Alameddine. "Selective removal of toxic organic dyes using Trӧger base-containing sulfone copolymers made from a metal-free thiol-yne click reaction followed by oxidation." RSC Advances 11, no. 34 (2021): 21170–78. http://dx.doi.org/10.1039/d1ra03783h.

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Copolymers TCP1–3 with Trӧger's base units and aryl thioether groups were made via a click reaction. Selective oxidation of the thioethers into sulfone groups afforded TCP4–6 which display up to 100% removal efficiency of methylene blue from water.

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Borja, Luis Claudio A., Sandro Fábio César, Rita Dione A. Cunha, and Asher Kiperstok. "Getting Environmental Information from Construction Cost Databases: Applications in Brazilian Courses and Environmental Assessment." Sustainability 11, no. 1 (January 1, 2019): 187. http://dx.doi.org/10.3390/su11010187.

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The traditional decision-making process in construction is still driven by factors such as cost and time, not adequately addressing indicators to control their environmental impacts. So, how to improve environmental communication to incorporate sustainable building practices. The incorporation of environmental indicators may enlarge the scope of construction management tools. In the case of cost databases, widely used in the construction sector, this action can contribute to the communication and dissemination of environmental practices. This paper mapped 24 indicators from construction cost databases to assess their ability to communicate and disseminate environmental information. The research comprised: (a) a review of the use of cost bases in the environmental study, (b) identification of the most cited bases in 27 Brazilian civil engineering courses, and (c) analysis of the selected databases through of the assessment matrix, it crosses cost data versus environmental information. CYPE, TCPO, and ORSE presented performance medium, and higher results than SINAPI, BDCCM, and BCCA. The tools presented low control over environmental information, such as water and energy consumption, machine circulation and pollution generation. However, it has been observed that when adding environmental indicators, these tools can contribute significantly to disseminate good practices in its wide user base.

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Juachon, Maria Janine, Justine Grace Regala, John Matthew Marquez, and Mark Xavier Bailon. "A proposed image-based detection of methamidophos pesticide using peroxyoxalate chemiluminescence system." Open Chemistry 17, no. 1 (April 24, 2019): 270–78. http://dx.doi.org/10.1515/chem-2019-0034.

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AbstractPesticides pose a serious public health risk due to their toxicity, such as in the case of the widely distributed organophosphorus pesticide methamidophos. There is a strong need to develop a simple, rapid, and cost-effective method of detecting methamidophos residues; thus, this study proposes the TCPO-Rubrene-H2O2 chemiluminescence (CL) system as a means of pesticide detection via quenching effect. The results show that the methamidophos concentration is inversely proportional to the CL system's light output as confirmed through fluorescence spectroscopy and Batch Measure Macro (BMM) analysis. The light intensity differences were correlated with the methamidophos concentration with both methods showing linear trends. Both the digital camera and the smartphone camera BMM analyses displayed good sensitivity, with respective detection limits of 1.6 μg/mL and 1.0 μg/mL and respective quantitation limits of 5.0 μg/mL and 3.0 μg/mL. Both also showed good linearity within the 100-10000 μg/mL range, suggesting viability as alternatives to the fluorescence spectrometer; however, the light intensity difference values per pesticide concentration of both camera systems were significantly different from one another owing to differences in camera features.

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Habault, P., D. Eveno, S. Le Lamer, M. Ledemeney, C. Haon, and D. Chomard. "Criteria Predictive of Limb Viability at 1 Year in Patients with Chronic Severe Ischemia-TcPO 2 and Demographic Parameters." Angiology 51, no. 9 (September 2000): 765–76. http://dx.doi.org/10.1177/000331970005100909.

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Moore, Wesley S., and Andreas S. Scheffler. "A comparative analysis of transcutaneous oximetry (tcPo) during oxygen inhalation and leg dependency in severe peripheral arterial occlusive disease." Journal of Vascular Surgery 16, no. 2 (August 1992): 0218–24. http://dx.doi.org/10.1067/mva.1992.36659.

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Biparva, Pourya, Seyed Mohammad Abedirad, and Sayed Yahya Kazemi. "Silver nanoparticles enhanced a novel TCPO–H 2 O 2 –safranin O chemiluminescence system for determination of 6-mercaptopurine." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 145 (June 2015): 454–60. http://dx.doi.org/10.1016/j.saa.2015.03.019.

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Spears, Benjamin J., T. C. Howton, Fei Gao, Christopher M. Garner, M. Shahid Mukhtar, and Walter Gassmann. "Direct Regulation of the EFR-Dependent Immune Response by Arabidopsis TCP Transcription Factors." Molecular Plant-Microbe Interactions® 32, no. 5 (May 2019): 540–49. http://dx.doi.org/10.1094/mpmi-07-18-0201-fi.

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One layer of the innate immune system allows plants to recognize pathogen-associated molecular patterns (PAMPS), activating a defense response known as PAMP-triggered immunity (PTI). Maintaining an active immune response, however, comes at the cost of plant growth and development; accordingly, optimization of the balance between defense and development is critical to plant fitness. The TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP) transcription factor family consists of well-characterized transcriptional regulators of plant development and morphogenesis. The three closely related class I TCP transcription factors TCP8, TCP14, and TCP15 have also been implicated in the regulation of effector-triggered immunity, but there has been no previous characterization of PTI-related phenotypes. To identify TCP targets involved in PTI, we screened a PAMP-induced gene promoter library in a yeast one-hybrid assay and identified interactions of these three TCPs with the EF-Tu RECEPTOR (EFR) promoter. The direct interactions between TCP8 and EFR were confirmed to require an intact TCP binding site in planta. A tcp8 tcp14 tcp15 triple mutant was impaired in EFR-dependent PTI and exhibited reduced levels of PATHOGENESIS-RELATED PROTEIN 2 and induction of EFR expression after elicitation with elf18 but also increased production of reactive oxygen species relative to Col-0. Our data support an increasingly complex role for TCPs at the nexus of plant development and defense.

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Yang, Woorim, Myung-Hwan Choi, Bosl Noh, and Yoo-Sun Noh. "De Novo Shoot Regeneration Controlled by HEN1 and TCP3/4 in Arabidopsis." Plant and Cell Physiology 61, no. 9 (June 24, 2020): 1600–1613. http://dx.doi.org/10.1093/pcp/pcaa083.

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Abstract Plants have the ability to regenerate whole plant body parts, including shoots and roots, in vitro from callus derived from a variety of tissues. However, the underlying mechanisms for this de novo organogenesis, which is based on the totipotency of callus cells, are poorly understood. Here, we report that a microRNA (miRNA)-mediated posttranscriptional regulation plays an important role in de novo shoot regeneration. We found that mutations in HUA ENHANCER 1 (HEN1), a gene encoding a small RNA methyltransferase, cause cytokinin-related defects in de novo shoot regeneration. A hen1 mutation caused a large reduction in the miRNA319 (miR319) level and a subsequent increase in its known target (TCP3 and TCP4) transcript levels. TCP transcription factors redundantly inhibited shoot regeneration and directly activated the expression of a negative regulator of cytokinin response ARABIDOPSIS THALIANA RESPONSE REGULATOR 16 (ARR16). A tcp4 mutation at least partly rescued the shoot-regeneration defect and derepression of ARR16 in hen1. These findings demonstrate that the miR319-TCP3/4-ARR16 axis controls de novo shoot regeneration by modulating cytokinin responses.

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Althurwi, Safiah Ibrahim, Jun Q. Yu, Philip Beale, and Fazlul Huq. "Sequenced Combinations of Cisplatin and Selected Phytochemicals towards Overcoming Drug Resistance in Ovarian Tumour Models." International Journal of Molecular Sciences 21, no. 20 (October 12, 2020): 7500. http://dx.doi.org/10.3390/ijms21207500.

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In the present study, cisplatin, artemisinin, and oleanolic acid were evaluated alone, and in combination, on human ovarian A2780, A2780ZD0473R, and A2780cisR cancer cell lines, with the aim of overcoming cisplatin resistance and side effects. Cytotoxicity was assessed by MTT reduction assay. Combination index (CI) values were used as a measure of combined drug effect. MALDI TOF/TOF MS/MS and 2-DE gel electrophoresis were used to identify protein biomarkers in ovarian cancer and to evaluate combination effects. Synergism from combinations was dependent on concentration and sequence of administration. Generally, bolus was most synergistic. Moreover, 49 proteins differently expressed by 2 ≥ fold were: CYPA, EIF5A1, Op18, p18, LDHB, P4HB, HSP7C, GRP94, ERp57, mortalin, IMMT, CLIC1, NM23, PSA3,1433Z, and HSP90B were down-regulated, whereas hnRNPA1, hnRNPA2/B1, EF2, GOT1, EF1A1, VIME, BIP, ATP5H, APG2, VINC, KPYM, RAN, PSA7, TPI, PGK1, ACTG and VDAC1 were up-regulated, while TCPA, TCPH, TCPB, PRDX6, EF1G, ATPA, ENOA, PRDX1, MCM7, GBLP, PSAT, Hop, EFTU, PGAM1, SERA and CAH2 were not-expressed in A2780cisR cells. The proteins were found to play critical roles in cell cycle regulation, metabolism, and biosynthetic processes and drug resistance and detoxification. Results indicate that appropriately sequenced combinations of cisplatin with artemisinin (ART) and oleanolic acid (OA) may provide a means to reduce side effects and circumvent platinum resistance.

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Matus, V., M. A. Sánchez, M. Martínez, and B. González. "Efficient Degradation of 2,4,6-Trichlorophenol Requires a Set of Catabolic Genes Related to tcp Genes from Ralstonia eutropha JMP134(pJP4)." Applied and Environmental Microbiology 69, no. 12 (December 2003): 7108–15. http://dx.doi.org/10.1128/aem.69.12.7108-7115.2003.

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ABSTRACT 2,4,6-Trichlorophenol (2,4,6-TCP) is a hazardous pollutant. Several aerobic bacteria are known to degrade this compound. One of these, Ralstonia eutropha JMP134(pJP4), a well-known, versatile chloroaromatic compound degrader, is able to grow in 2,4,6-TCP by converting it to 2,6-dichlorohydroquinone, 6-chlorohydroxyquinol, 2-chloromaleylacetate, maleylacetate, and β-ketoadipate. Three enzyme activities encoded by tcp genes, 2,4,6-TCP monooxygenase (tcpA), 6-chlorohydroxyquinol 1,2-dioxygenase (tcpC), and maleylacetate reductase (tcpD), are involved in this catabolic pathway. Here we provide evidence that all these tcp genes are clustered in the R. eutropha JMP134(pJP4) chromosome, forming the putative catabolic operon tcpRXABCYD. We studied the presence of tcp-like gene sequences in several other 2,4,6-TCP-degrading bacterial strains and found two types of strains. One type includes strains belonging to the Ralstonia genus and possessing a set of tcp-like genes, which efficiently degrade 2,4,6-TCP and therefore grow in liquid cultures containing this chlorophenol as a sole carbon source. The other type includes strains belonging to the genera Pseudomonas, Sphingomonas, or Sphingopixis, which do not have tcp-like gene sequences and degrade this pollutant less efficiently and which therefore grow only as small colonies on plates with 2,4,6-TCP. Other than strain JMP134, none of the bacterial strains whose genomes have been sequenced possesses a full set of tcp-like gene sequences.

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Krishnan, H. H., Amalendu Ghosh, Kalidas Paul, and Rukhsana Chowdhury. "Effect of Anaerobiosis on Expression of Virulence Factors in Vibrio cholerae." Infection and Immunity 72, no. 7 (July 2004): 3961–67. http://dx.doi.org/10.1128/iai.72.7.3961-3967.2004.

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ABSTRACT In Vibrio cholerae, the transmembrane DNA binding proteins, ToxR and TcpP, activate expression of the regulatory gene toxT in response to specific environmental signals. The resulting enhanced level of ToxT leads to a coordinated increase in the production of a subset of virulence factors, including cholera toxin (CT) and toxin-coregulated pilus (TCP). The effect of anaerobiosis on expression of the V. cholerae virulence regulatory cascade was examined. The expression of the major regulatory genes, tcpP, toxR, and toxT, in anaerobically grown V. cholerae was comparable to that in cells grown under aerobic conditions, and no significant difference in the ToxT-dependent expression of tcpA was detected when aerobic and anaerobic cultures were compared. However, in spite of the presence of functional ToxT, ctxAB expression was drastically reduced, and practically no CT was detected in cells grown under anaerobic conditions. In a V. cholerae hns mutant, however, high levels of ctxAB expression occurred even under anaerobic conditions. Also, deletion of the H-NS binding site from the ctxAB promoter eliminated anaerobic repression of ctxAB expression. These results suggest that H-NS directly represses ctxAB expression under anaerobic growth conditions. It has been reported that in the first stage of infection of infant mice by V. cholerae, tcpA is expressed but ctxAB expression is shut off (S. H. Lee, D. L. Hava, M. K. Waldor, and A. Camilli, Cell 99: 625-634, 1999). This pattern is similar to the pattern in anaerobic cultures of V. cholerae. Under all other in vitro conditions, ctxAB and tcpA are known to be coordinately expressed.

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Soares, Adrielle Naiana Ribeiro, Ana Veruska Cruz da Silva, Evandro Neves Muniz, Marília Freitas de Vasconcelos Melo, Priscilla Santana Santos, and Ana da Silva Ledo. "Biometry, Emergence and Initial Growth of Accessions and Mangaba Progenies." Journal of Agricultural Science 11, no. 4 (March 15, 2019): 436. http://dx.doi.org/10.5539/jas.v11n4p436.

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Mangaba (Hancornia speciosa Gomes) is a native fruit of great economic, cultural, and environmental importance in its areas of occurrence. Due to extractive activities and real estate pressure, the number of natural populations has considerably decreased. The propagation of the species is still one of the primary obstacles for orchard implantations, thus, studies that provide a better understanding of the dynamics of the species’ growth should be developed. This work aimed to evaluate the biometry, emergence, and initial growth of mangaba progenies (Hancornia speciosa Gomes), using the plant material from the Active Germplasm Bank of Embrapa Coastal Tablelands, located in Itaporanga d’Ajuda, SE, Brazil. Treatments consisted of progenies from 17 accessions. The experiment was carried out in a completely randomized design with four replications of 25 seeds. Number of seeds per fruit, as well as fruit and seed weight (g), length (mm), width (mm), and thickness (mm) were evaluated. For emergence and initial growth, the following variables were analyzed: percentage of emergence (PE%), emergence speed index (ESI%), survival rate (SR%), height (H), stem diameter (SD), and the number of leaves (NL). Biometric analyses of fruits and seeds revealed significant phenotypic variability among mangaba accessions. Progenies of the accessions LGP1, LGP3, LGP4, PTP4, TCP2, TCP6, ABP1, ABP2, ABP4 and BIP4 showed better results for all emergence and initial growth variables. The progenies of accessions TCP1, BIP4, CAP5 and PRP5 expressed lower emergence and survival percentages, and low vigor.

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Molaee, Neda, Ghasem Mosayebi, Alireza Amozande-Nobaveh, Mohammad Reza Soleyman, and Hamid Abtahi. "Evolution of the Immune Response against Recombinant Proteins (TcpA, TcpB, and FlaA) as a Candidate Subunit Cholera Vaccine." Journal of Immunology Research 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/2412747.

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Vibrio choleraeis the causative agent of cholera and annually leads to death of thousands of people around the globe. Two factors in the pathogenesis of this bacterium are its pili and flagella. The main subunits of pili TcpA, TcpB, and FlaA are the constituent subunit of flagella. In this study, we studied the ability of pili and flagella subunits to stimulate immune responses in mice. After amplification of TcpA, TcpB, and FlaA genes using PCR, they were cloned in expression plasmids. After production of the above-mentioned proteins by using IPTG, the proteins were purified and then approved using immunoblot method. After injection of the purified proteins to a mice model, immune response stimulation was evaluated by measuring the levels of IgG1 and IgG2a antibody titers, IL5 and IFN-γ. Immune response stimulation against pili and flagella antigens was adequate. Given the high levels of IL5 titer and IgG1 antibody, the stimulated immune response was toward Th1. Humoral immune response stimulation is of key importance in prevention of cholera. Our immunological analysis shows the appropriate immune response in mice model after vaccination with recombinant proteins. The high level of IL5 and low level of IFN-γshow the activation of Th2 cell response.

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Withey, Jeffrey H., and Victor J. DiRita. "Vibrio cholerae ToxT Independently Activates the Divergently Transcribed aldA and tagA Genes." Journal of Bacteriology 187, no. 23 (December 1, 2005): 7890–900. http://dx.doi.org/10.1128/jb.187.23.7890-7900.2005.

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ABSTRACT The Vibrio cholerae ToxT regulon includes the genes encoding cholera toxin (CT) and the toxin-coregulated pilus (TCP), which are the major virulence factors required for causing cholera disease and colonizing the upper small intestine of the host, respectively. The genes encoding CT, ctxAB, and the genes encoding the components of the TCP, tcpA to tcpJ, are organized within operons, upstream of which are DNA binding sites for the transcriptional activator ToxT. ToxT is a member of the large AraC/XylS family of transcriptional regulators and also activates transcription of five other genes whose roles in V. cholerae pathogenesis, if any, are poorly understood. acfA and acfD are divergently transcribed genes required for efficient colonization of the intestine. Transcriptional activation of acfA and acfD requires a pair of central ToxT binding sites in an inverted-repeat configuration for ToxT-directed transcription of both genes. tcpI has an unknown role in pathogenesis. aldA and tagA are divergently transcribed genes that also have unknown roles in pathogenesis. In this study, we map the aldA and tagA promoters and identify the ToxT binding sites upstream of each gene. Our results suggest that two ToxT binding sites in an inverted-repeat configuration are required for ToxT-directed transcription of tagA and that a single ToxT binding site is required for ToxT-directed transcription of aldA. Furthermore, to direct transcription of tagA and aldA, ToxT uses independent binding regions upstream of each gene, in contrast to what we previously found for the divergently transcribed acfA and acfD genes, which share ToxT binding sites between the two genes.

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Thomas, Catherine, Michel Mosnier, Gérard Percebois, Gérard Debry, and J. P. Pointel. "tcpO 2, Arterial Blood Flow and Lactate/Pyruvate Modifications Induced by a Single Dose of Naftidrofuryl IV During Stage III Lower-Limb Arteriopathies." Angiology 37, no. 9 (August 1986): 647–53. http://dx.doi.org/10.1177/000331978603700905.

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Rivera, Irma N. G., Jongsik Chun, Anwar Huq, R. Brad Sack, and Rita R. Colwell. "Genotypes Associated with Virulence in Environmental Isolates of Vibrio cholerae." Applied and Environmental Microbiology 67, no. 6 (June 1, 2001): 2421–29. http://dx.doi.org/10.1128/aem.67.6.2421-2429.2001.

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ABSTRACT Vibrio cholerae is an autochthonous inhabitant of riverine and estuarine environments and also is a facultative pathogen for humans. Genotyping can be useful in assessing the risk of contracting cholera, intestinal, or extraintestinal infections via drinking water and/or seafood. In this study, environmental isolates ofV. cholerae were examined for the presence of ctxA, hlyA, ompU, stn/sto, tcpA, tcpI, toxR, and zot genes, using multiplex PCR. Based on tcpA and hlyAgene comparisons, the strains could be grouped into Classical and El Tor biotypes. The toxR, hlyA, and ompU genes were present in 100, 98.6, and 87.0% of the V. choleraeisolates, respectively. The CTX genetic element and toxin-coregulated pilus El Tor (tcpA ET) gene were present in all toxigenicV. cholerae O1 and V. cholerae O139 strains examined in this study. Three of four nontoxigenic V. cholerae O1 strains contained tcpA ET. Interestingly, among the isolates of V. cholerae non-O1/non-O139, two hadtcpA Classical, nine contained tcpA El Tor, three showed homology with both biotype genes, and four carried thectxA gene. The stn/sto genes were present in 28.2% of the non-O1/non-O139 strains, in 10.5% of the toxigenicV. cholerae O1, and in 14.3% of the O139 serogroups. Except for stn/sto genes, all of the other genes studied occurred with high frequency in toxigenic V. cholerae O1 and O139 strains. Based on results of this study, surveillance of non-O1/non-O139 V. cholerae in the aquatic environment, combined with genotype monitoring using ctxA, stn/sto, andtcpA ET genes, could be valuable in human health risk assessment.

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MESEGUERLLORET, S. "FI automatic method for the determination of copper(II) based on coproporphyrin I?Cu(II)/TCPO/H2O2 chemiluminescence reaction for the screening of waters." Talanta 64, no. 4 (November 2004): 1030–35. http://dx.doi.org/10.1016/j.talanta.2004.05.004.

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Molins-Legua, C., P. Campíns-Falcó, and A. Sevillano-Cabeza. "Automated pre-column derivatization of amines in biological samples with dansyl chloride and with or without post-column chemiluminescence formation by using TCPO–H2O2." Analyst 123, no. 12 (1998): 2871–76. http://dx.doi.org/10.1039/a805266b.

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Chaichi, M. J., and S. O. Alijanpour. "Determination of vitamin C in drugs using of an optimized novel TCPO–Amplex red–gold/silver alloy nanoparticles–H2O2 chemiluminescence method by the Box–Behnken design." Journal of Luminescence 134 (February 2013): 195–200. http://dx.doi.org/10.1016/j.jlumin.2012.08.048.

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Bhanumathi, R., F. Sabeena, Sree Renjini Isac, B. N. Shukla, and D. V. Singh. "Molecular Characterization of Vibrio cholerae O139 Bengal Isolated from Water and the Aquatic Plant Eichhornia crassipes in the River Ganga, Varanasi, India." Applied and Environmental Microbiology 69, no. 4 (April 2003): 2389–94. http://dx.doi.org/10.1128/aem.69.4.2389-2394.2003.

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ABSTRACT A collection of ten strains of Vibrio cholerae O139, comprising six isolates from Eichhornia crassipes, two from water of the River Ganga, and one each from a well and a hand pump, were characterized. All the strains carried the CTX genetic element (ctxA, zot, and ace) except for the st gene and carried structural and regulatory genes for toxin-coregulated pilus (tcpA, tcpI, and toxR), adherence factor (ompU), and accessory colonization factor (acfB); all produced cholera toxin (CT). These strains were resistant to trimethoprim, sulfamethoxazole, streptomycin, and to the vibriostatic agent pteridine. Results obtained by ribotyping and enterobacterial repetitive intergenic consensus sequence-PCR fingerprint analysis indicate that multiple clones of toxigenic-pathogenic V. cholerae O139 were present in the aquatic environment.

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Journal articles on the topic 'TCPO'

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