Artigos de revistas: "Confined compartment"

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Heasley, Lydia R., Steven M. Markus e Jennifer G. DeLuca. "“Wait anaphase” signals are not confined to the mitotic spindle". Molecular Biology of the Cell 28, n.º 9 (maio de 2017): 1186–94. http://dx.doi.org/10.1091/mbc.e17-01-0036.

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The spindle assembly checkpoint ensures the faithful inheritance of chromosomes by arresting mitotic progression in the presence of kinetochores that are not attached to spindle microtubules. This is achieved through inhibition of the anaphase-promoting complex/cyclosome by a kinetochore-derived “wait anaphase” signal known as the mitotic checkpoint complex. It remains unclear whether the localization and activity of these inhibitory complexes are restricted to the mitotic spindle compartment or are diffusible throughout the cytoplasm. Here we report that “wait anaphase” signals are indeed able to diffuse outside the confines of the mitotic spindle compartment. Using a cell fusion approach to generate multinucleate cells, we investigate the effects of checkpoint signals derived from one spindle compartment on a neighboring spindle compartment. We find that spindle compartments in close proximity wait for one another to align all chromosomes before entering anaphase synchronously. Synchrony is disrupted in cells with increased interspindle distances and cellular constrictions between spindle compartments. In addition, when mitotic cells are fused with interphase cells, “wait anaphase” signals are diluted, resulting in premature mitotic exit. Overall our studies reveal that anaphase inhibitors are diffusible and active outside the confines of the mitotic spindle from which they are derived.

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Schmidt, Kathleen. "Which Linear Compartmental Systems Can Be Analyzed by Spectral Analysis of PET Output Data Summed over All Compartments?" Journal of Cerebral Blood Flow & Metabolism 19, n.º 5 (maio de 1999): 560–69. http://dx.doi.org/10.1097/00004647-199905000-00010.

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General linear time-invariant compartmental systems were examined to determine which systems meet the conditions necessary for application of the spectral analysis technique to the sum of the concentrations in all compartments. Spectral analysis can be used to characterize the reversible and irreversible components of the system and to estimate the minimum number of compartments, but it applies only to systems in which the measured data can be expressed as a positively weighted sum of convolution integrals of the input function with an exponential function that has real-valued nonpositive decay constants. The conditions are met by compartmental systems that are strongly connected, have exchange of material with the environment confined to a single compartment, and do not contain cycles, i.e., there is no possibility for material to pass from one compartment through two or more compartments back to the initial compartment. Certain noncyclic systems with traps, systems with cycles that obey a specified loop condition, and noninterconnected collections of such systems also meet the conditions. Dynamic positron emission tomographic data obtained after injection of a radiotracer, the kinetics of which can be described by any model in the class of models identified here, can be appropriately analyzed with the spectral analysis technique.

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Chan, Michael W., Isabelle Thibault, Eshetu G. Atenafu, Eugene Yu, B. C. John Cho, Daniel Letourneau, Young Lee, Albert Yee, Michael G. Fehlings e Arjun Sahgal. "Patterns of epidural progression following postoperative spine stereotactic body radiotherapy: implications for clinical target volume delineation". Journal of Neurosurgery: Spine 24, n.º 4 (abril de 2016): 652–59. http://dx.doi.org/10.3171/2015.6.spine15294.

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OBJECT The authors performed a pattern-of-failure analysis, with a focus on epidural disease progression, in patients treated with postoperative spine stereotactic body radiotherapy (SBRT). METHODS Of the 70 patients with 75 spinal metastases (cases) treated with postoperative spine SBRT, there were 26 cases of local disease recurrence and 25 cases with a component of epidural disease progression. Twenty-four of the 25 cases had preoperative epidural disease with subsequent epidural disease progression, and this cohort was the focus of this epidural-specific pattern-of-failure investigation. Preoperative, postoperative, and follow-up MRI scans were reviewed, and epidural disease was characterized based on location according to a system in which the vertebral anatomy is divided into 6 sectors, with the anterior compartment comprising Sectors 1, 2, and 6, and the posterior compartment comprising Sectors 3, 4, and 5. RESULTS Patterns of epidural progression are reported specifically for the 24 cases with preoperative epidural disease and subsequent epidural progression. Epidural disease progression within the posterior compartment was observed to be significantly lower in those with preoperative epidural disease confined to the anterior compartment than in those with preoperative epidural disease involving both anterior and posterior compartments (56% vs 93%, respectively; p = 0.047). In a high proportion of patients with epidural disease progression, treatment failure was found in the anterior compartment, including both those with preoperative epidural disease confined to the anterior compartment and those with preoperative epidural disease involving both anterior and posterior compartments (100% vs. 73%, respectively). When epidural disease was confined to the anterior compartment on the preoperative and postoperative MRIs, no epidural disease progression was observed in Sector 4, which is the most posterior sector. Postoperative epidural disease characteristics alone were not predictive of the pattern of epidural treatment failure. CONCLUSIONS Reviewing the extent of epidural disease on preoperative MRI is imperative when planning postoperative SBRT. When epidural disease is confined to the anterior epidural sectors pre- and postoperatively, covering the entire epidural space circumferentially with a prophylactic “donut” distribution may not be needed.

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Salvado, Francisco C., Arikson J. Tavares, F. Teixeira-Dias e João B. Cardoso. "Confined explosions: The effect of compartment geometry". Journal of Loss Prevention in the Process Industries 48 (julho de 2017): 126–44. http://dx.doi.org/10.1016/j.jlp.2017.04.013.

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Dwyer, C. Liam, Maximillian C. Soong e N. George Kasparyan. "Chronic Exertional Compartment Syndrome of the Hand: Case Report and Literature Review". HAND 12, n.º 3 (15 de setembro de 2016): NP43—NP45. http://dx.doi.org/10.1177/1558944716668826.

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Background: Chronic exertional compartment syndrome (CECS) is characterized by activity-induced pain, swelling, and decreased muscle function due to increased pressure and decreased circulation within a confined muscle compartment. Although well-known to occur in the leg, involvement of the hand has rarely been reported in the literature. Methods: We present a 44 year old male with CECS involving bilateral thenar and hypothenar compartments. Symptoms were reproduced on exam by driving screws into wood with a screwdriver. Elevated compartment pressures were confirmed with a hand-held digital device which employs a rigid needle that is readily directed to specific compartments. Results: Selective releases of the thenar and hypothenar compartments were performed under local anesthesia and forearm tourniquet in the ambulatory surgery center. At 3-month follow-up, the patient reported full use of his right hand, including woodworking, with excellent relief of symptoms. At 5 months postoperatively, he underwent identical surgical releases on the contralateral left side, with similar relief. Conclusions: CECS of the hand is a rare condition. Our case is unique among prior reports with regard to pattern of compartment involvement, as well as provocative maneuvers and compartment testing methods employed. This report should help foster clinical suspicion, facilitate diagnosis, and demonstrate success of targeted surgical treatment.

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Armstrong, J. B., P. K. Rose, S. Vanner, G. J. Bakker e F. J. Richmond. "Compartmentalization of motor units in the cat neck muscle, biventer cervicis". Journal of Neurophysiology 60, n.º 1 (1 de julho de 1988): 30–45. http://dx.doi.org/10.1152/jn.1988.60.1.30.

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1. The neck muscle biventer cervicis is supplied by five separate nerve bundles that originate from segments C2-C5 and enter the muscle at different rostrocaudal levels. We have used the glycogen-depletion method to investigate the distribution of muscle fibers supplied by each nerve bundle and also the extent of motor-unit territories supplied by single motoneurons in the C3 segment. 2. Prolonged intermittent stimulation of each nerve bundle produced glycogen depletion in a compartment of muscle fibers that ran only a fraction of the whole-muscle length. The depleted compartment was separated by tendinous inscriptions from adjacent, serially arranged compartments that were supplied by different nerve bundles. Thus the muscle was divided into five in-series compartments, arranged in the same rostrocaudal sequence as the nerves by which they were supplied. 3. Six fast, glycolytic (FG) and five fast, oxidative-glycolytic (FOG) motor units were depleted by repetitive intracellular stimulation of their antidromically identified motoneurons in the C3 segment. The fibers of each motor unit were confined to a striplike subvolume whose cross-sectional area was only 20-40% of that for the whole compartment in which it was located. Single motor units contained an average of 408 extrafusal fibers (range: 262-582 fibers), and these were distributed with an average density of 20 fibers/mm2 in cross sections through their motor domains. No significant differences were found between the numbers or densities of fibers in FG and FOG motor units. 4. The specialized in-series organization of compartments has functional implications because the forces generated by one compartment of motor units must be transmitted through other in-series compartments of muscle fibers rather than directly onto skeletal attachments. The confined distribution of muscle fibers belonging to a single motor unit suggests that an additional level of organization may exist within individual compartments. The implications of these features for the physiological behavior and neural control of biventer cervicis are discussed.

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Wang, Aijuan, Brady Manescau, Khaled Chetehouna, Steve Rudz e Ludovic Lamoot. "Experimental study on the flame extension and risk analysis of a diffusion impinging flame in confined compartment". Journal of Fire Sciences 39, n.º 4 (17 de junho de 2021): 285–308. http://dx.doi.org/10.1177/07349041211015766.

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In this work, an experimental investigation on a diffusion impinging flame in a confined compartment was performed. The objective was to study the influence of confinement on the behavior of a flame impinging the ceiling and to deduce the auto-ignition risk of the smoke produced in the confined compartment. For this, configurations with five confinement levels were constructed by the condition of windows and/or door in the compartment and the variation of the heat release rates was made between 0.5 and 18.6 kW. To evaluate the flame morphology and flame extension length, an image processing method based on the direct linear transformation algorithm and the fire segmentation algorithm was adopted. From the experimental data, it was shown that the heat release rate of 4.6 kW presents a critical value for the flame extension in confined configurations, which corresponds to the equivalence ratio of the enclosure greater than 1, highlighting an under-ventilated environment. In addition, an auto-ignition risk analysis of smoke with unburnt gas in the compartment was carried out. The concentration and temperature of these gases were compared to the lower flammability limits and the auto-ignition temperature. It was observed that there was auto-ignition risk of the smoke under the ceiling, especially in the confined compartment of equivalence ratio greater than 1. Under these conditions, it is possible to have a fire spread to another compartment.

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Yadav, VedPal, Anil Juyal e Sansar Sharma. "Evaluation of lateral closed wedge high tibial osteotomy for medial compartment osteoarthritis". Bangladesh Journal of Medical Science 14, n.º 4 (11 de dezembro de 2015): 389–92. http://dx.doi.org/10.3329/bjms.v14i4.18584.

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Introduction: Osteoarthritis of the knee is a common orthopaedic condition. Medial compartment osteoarthritis results from undue stress on the medial compartment of the knee joint following varus deformity. High tibial osteotomy (HTO) has been a long-standing treatment for osteoarthritis of the medial compartment of the knee. Although knee replacement has gained wide popularity for its treatment, still HTO is a good and cost effective procedure for young patients having good range of motion and uni-compartmental involvement. Objective: To evaluate the results of HTO in medial compartment osteoarthritis. Methods and Material: This study was conducted in a tertiary care teaching hospital of North India over a period of 3 years. The patients with disabling knee pain due to medial compartment osteoarthrosis with genu varus deformity refractory to conservative treatment were treated by High Tibial Osteotomy. Results: Overall 40 patients with medial compartmental osteoarthritis were treated with HTO. Patients were evaluated for the severity of pain as per Visual Analogue Score (VAS). There was satisfactory pain reduction (up to 80%) in most of the patients. Conclusions: HTO is a good procedure for young patients with good range of motion and changes confined to one compartment only.Bangladesh Journal of Medical Science Vol.14(4) 2015 p.389-392

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Songyang Li, Ruowen Zong, Lvyi Chen, Tao Wei e Guangxuan Liao. "Effect of Different Fuels on Confined Compartment Fire". Journal of Fire Sciences 28, n.º 4 (4 de dezembro de 2009): 383–403. http://dx.doi.org/10.1177/0734904109350192.

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Elhadi, Hashim Mohamed. "Effect of Diet Quality and Housing on Water Status in Sudanese Desert Sheep and Goats". Journal of Agricultural and Marine Sciences [JAMS] 15 (1 de janeiro de 2010): 29. http://dx.doi.org/10.24200/jams.vol15iss0pp29-32.

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Two independent experiments were carried out using Sudanese Desert sheep and goats to investigate water metabolism (total body water, TBW and water turnover, WTO) and internal water compartments using radioactive water (tritium), under natural grazing conditions in a semi-desert area. The second trial was carried out on confined sheep, fed high (Lucerne) and poor quality (desert grasses) diets. The body weights, rectal temperature and water parameters were monitored in both trials and species under the Sudanese summer conditions. The grazing animal’s body weights were reduced compared to confined ones. Hyperthermia was pronounced in goats (9%) compared to sheep (6%). The goat hyperthermia was associated with high water turnover, indicating the poor heat tolerance of this species of high evaporative cooling. The confined animals, however, maintained their body weights and did not show signs of hyperthermia. The poor diet (desert grasses) was associated with reduced water intake whereas the Lucerne was associated with high water turnover and high feed intake. The extracelluar compartment (ECV) was higher with the poor diet but was lower than the grazing group. The intracellular compartment (ICV) was higher in the Lucerne group. The study indicated that Sudanese Desert sheep are more tolerant to high temperatures and grazing system than goats.

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Santos, Elena C. dos, Alessandro Angelini, Dimitri Hürlimann, Wolfgang Meier e Cornelia G. Palivan. "Giant Polymer Compartments for Confined Reactions". Chemistry 2, n.º 2 (12 de maio de 2020): 470–89. http://dx.doi.org/10.3390/chemistry2020028.

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In nature, various specific reactions only occur in spatially controlled environments. Cell compartment and subcompartments act as the support required to preserve the bio-specificity and functionality of the biological content, by affording absolute segregation. Inspired by this natural perfect behavior, bottom-up approaches are the focus to develop artificial cell-like structures, detrimental for understanding relevant bioprocesses and interactions or to produce tailored solutions in the field of therapeutics and diagnostics. In this review, we discuss the benefits of constructing polymer-based single and multicompartments (capsules and giant unilamellar vesicles (GUVs)), equipped with biomolecules as to mimic cells. In this respect, we outline key examples of how such structures have been designed from scratch, namely starting from the application-oriented selection and synthesis of the amphiphilic block copolymer. We then present the state-of-the-art techniques for assembling the supramolecular structure while permitting the encapsulation of active compounds and the incorporation of specific ion channels (peptides/proteins), essential to support in situ reactions, e.g., to replicate intracellular signaling cascades. Finally, we briefly discuss important features that these compartments offer and how they could be applied to engineer the next generation of microreactors, therapeutic solutions, and cell models.

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Simoni, G., S. M. Sirchia e M. Fraccaro. "Aneuploid Correction and Confined Placental Mosaicism". Acta geneticae medicae et gemellologiae: twin research 45, n.º 1-2 (abril de 1996): 153–61. http://dx.doi.org/10.1017/s0001566000001240.

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Uniparental disomy (UPD) can be caused by various genetic mechanisms such as gamete complementation, chromosome duplication in a monosomic zygote or postzygotic aneuploid correction. This latter mechanism has been recently well documented in human reproduction and seems to be strictly related to placental mosaicism. We have therefore studied some aspects of confined placental mosaicism (CPM) which are useful to clarify one of the most common sources of UPD in humans.Abnormal distribution of chromosomes in postzygotic mitotic cell divisions may result in a mosaic condition with two or more cell lines showing different chromosome constitutions. The effects on fetal phenotype and pregnancy development depend on the chromosomes involved, the distribution of the abnormal cells among tissues and on the precise stage at which chromosome mutation occurs.As shown in Fig. 1, when the mutational event occurs in the blastocyst, prior to the differentiation of embryonic and chorionic compartments, the mosaicism is found in both the placental and fetal tissues. In contrast, when the chromosome mutation occurs at a later stage, after embryonic and chorionic compartment separation, the abnormal cells may be confined to the placenta or to the embryo, and are not necessarily found in both.

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Eun, Changsun. "Free Energy Profile for the Complete Transport of Nonpolar Molecules through a Carbon Nanotube". International Journal of Molecular Sciences 24, n.º 19 (26 de setembro de 2023): 14565. http://dx.doi.org/10.3390/ijms241914565.

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Gas molecules or weakly interacting molecules are commonly observed to diffuse through and fill space. Therefore, when the molecules initially confined in one compartment are allowed to move through a channel into another empty compartment, we expect that some molecules will be transported into the initially empty compartment. In this work, we thermodynamically analyze this transport process using a simple model consisting of graphene plates, a carbon nanotube (CNT), and nonpolar molecules that are weakly interacting with each other. Specifically, we calculate the free energy change, or the potential of mean force (PMF), as the molecules are transported from one compartment to another compartment. The PMF profile clearly exhibits a global minimum, or a free energy well, at the state wherein the molecules are evenly distributed over the two compartments. To better understand the thermodynamic origin of the well, we calculate the energetic and entropic contributions to the formation of the well, and we show that the entropic change is responsible for it and is the driving force for transport. Our work not only enables a fundamental understanding of the thermodynamic nature of the transport of weakly interacting molecules with molecular details, but also provides a method for calculating the free energy change during transport between two separate spaces connected by a nanochannel.

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Zhou, Min, Geng Ku, Laura Pageon e Chun Li. "Theranostic probe for simultaneous in vivo photoacoustic imaging and confined photothermolysis by pulsed laser at 1064 nm in 4T1 breast cancer model". Nanoscale 6, n.º 24 (2014): 15228–35. http://dx.doi.org/10.1039/c4nr05386a.

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Goldberg, Alexander A., Simon D. Bourque, Pavlo Kyryakov, Tatiana Boukh-Viner, Christopher Gregg, Adam Beach, Michelle T. Burstein et al. "A novel function of lipid droplets in regulating longevity". Biochemical Society Transactions 37, n.º 5 (21 de setembro de 2009): 1050–55. http://dx.doi.org/10.1042/bst0371050.

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Growing evidence supports the view that LDs (lipid droplets) are dynamic organelles that can serve both as an intracellular signalling compartment and as an organizing platform orchestrating many vital processes in eukaryotic cells. It has become clear that the LDs-confined deposition and lipolytic degradation of neutral lipids define longevity in multicellular eukaryotic organisms and yeast. We summarize the evidence in support of the essential role that LDs play in longevity regulation and propose several molecular mechanisms by which these dynamic organellar compartments control the aging process in multicellular eukaryotes and yeast.

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Genoud, Sian, Blaine R. Roberts, Adam P. Gunn, Glenda M. Halliday, Simon J. G. Lewis, Helen J. Ball, Dominic J. Hare e Kay L. Double. "Subcellular compartmentalisation of copper, iron, manganese, and zinc in the Parkinson's disease brain". Metallomics 9, n.º 10 (2017): 1447–55. http://dx.doi.org/10.1039/c7mt00244k.

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Yang, Cheng, Minjie Shi, Yuyu Tian, Jun Yang, Xuefeng Song, Liping Zhao, Jing Liu, Peng Zhang e Lian Gao. "Bioinspired pomegranate-like microflowers confining core-shell binary NixSy nanobeads for efficient supercapacitors exhibiting a durable lifespan exceeding 100 000 cycles". Journal of Materials Chemistry A 7, n.º 7 (2019): 3432–42. http://dx.doi.org/10.1039/c8ta11489g.

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Bridger, Joanna M., Claudia Kalla, Harald Wodrich, Sandra Weitz, Jason A. King, Khashayarsha Khazaie, Hans-Georg Kräusslich e Peter Lichter. "Nuclear RNAs confined to a reticular compartment between chromosome territories". Experimental Cell Research 302, n.º 2 (janeiro de 2005): 180–93. http://dx.doi.org/10.1016/j.yexcr.2004.07.038.

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Karuri, AR, AM Kumar e D. Mukhopadhyay. "Differential expression and selective localization of vascular permeability factor/vascular endothelial growth factor in the rat uterus during the estrous cycle". Journal of Endocrinology 159, n.º 3 (1 de dezembro de 1998): 489–99. http://dx.doi.org/10.1677/joe.0.1590489.

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This study examines the expression of the multi-functional cytokine, vascular permeability factor/vascular endothelial growth factor (VPF/VEGF) in the rat uterus during early proestrus, proestrus, estrus and diestrus. Groups of ovariectomized or hypophysectomized rats served as endocrine controls. Expression of VPF/VEGF mRNA was 2-fold greater in uteri during proestrus and estrus than in other phases of the estrous cycle. In situ hybridization techniques indicated that VPF/VEGF mRNA expression was confined to the luminal epithelium during proestrus, but shifted to the stromal compartment during estrus. Ovariectomized, hypophysectomized or diestrus rats exhibited scattered localization of VPF/VEGF mRNA among glandular epithelium and endometrial stromal compartments. Although VPF/VEGF mRNA was expressed throughout the estrous cycle, but in different compartments of the endometrium depending on the stage of the estrous cycle, VPF/VEGF protein expression appears to be restricted to the epithelial compartment during proestrus and estrus. Results indicate that circulating levels of gonadal steroids and LH may be associated with the differential expression of VPF/VEGF mRNA and its translation activity in the endometrium during different stages of the estrous cycle.

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Bello-Mendoza, Ricardo, e Paul N. Sharratt. "Analysis of Retention Time Distribution (RTD) curves in an anaerobic digester with confined-gas mixing using a compartment model". Water Science and Technology 40, n.º 8 (1 de outubro de 1999): 49–56. http://dx.doi.org/10.2166/wst.1999.0383.

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Stimulus-response experiments were conducted in a continuous vessel with a single, centrally mounted draft-tube. The obtained retention time distribution curves were then analysed using conventional methods. These resulted in contradictory interpretation of the experimental data. To overcome this problem, a compartment model was developed to represent the mixing behaviour of this type of system. This mixing model consists of an ideally mixed compartment around the uptake tube and two cascades of tanks-in-series describing the circulation flow. The adjustable parameters of the model are the volume of the ideally mixed compartment, the circulation time and the number of tanks in each circulation loop. These parameters were estimated by fitting simulations to experimental mixing curves. The model consistently described the improvement of mixing with volumetric power input. Furthermore, the correlations found between power input and model parameters allowed the prediction of independently measured pulse-response curves rather well. The proposed compartment model brings the prospect of coupling microbial kinetics to reactor hydraulics to quantify the impact of mixing on the performance of anaerobic sludge digesters.

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MORITA, Masamune, Yuri OTA e Naohiro NODA. "Microbial Culture and Detection Technology in a Confined Cell-sized Small Compartment". BUNSEKI KAGAKU 70, n.º 6 (5 de junho de 2021): 335–40. http://dx.doi.org/10.2116/bunsekikagaku.70.335.

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Chu, William, Jiun-Hung Lin, Shih-Tsang Tang, Woei-Chyn Chu, Shuenn-Tsong Young e Chia-Tai Chan. "A RAPID AND CONVENIENT METHOD FOR DETERMINING LIMB COMPARTMENT PRESSURE". Biomedical Engineering: Applications, Basis and Communications 23, n.º 06 (dezembro de 2011): 435–44. http://dx.doi.org/10.4015/s1016237211002815.

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Compartment syndrome (CS) is the pressure increasing within a confined anatomic space, which results in ischemia to the encompassed tissues and then leads to cells death. If left untreated, CS results in irreversible cell damage, further permanently postischemic scarring and contracture. The intracompartmental pressure is a major diagnostic consideration. Various methods of compartment pressure (CP) measurement have been developed since the late 1800s. They can be classified into invasive and noninvasive categories. Invasive methods are accurate but painful; whereas noninvasive approaches are more comfortable but less accurate. Both methods provide reproducible outcomes but also require specific CP measurement instrument to be performed. This research proposes a rapid and convenient method via examining ultrasonographic fascia wall displacement. For the viscoelastic nature of the compartment fascia, our experiment results have shown the ultrasonographic fascia displacement accurately reflects even small changes of the compartment diameter. There is a strong correlation between compartment pressure and fascia displacement ratio. It also recommends that the ratio of 1.4 could be chosen as the critical value for determining acute compartment syndrome. These results suggest that ultrasonography may serve as an adequate noninvasive tool to monitor CP variations.

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Zajicek, G., I. Ariel e N. Arber. "The streaming adrenal cortex: direct evidence of centripetal migration of adrenocytes by estimation of cell turnover rate". Journal of Endocrinology 111, n.º 3 (dezembro de 1986): 477–82. http://dx.doi.org/10.1677/joe.0.1110477.

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ABSTRACT Thirty adult male rats were injected with 0·5 μCi [3H]thymidine/g body weight (specific activity 5 Ci/ mmol) and killed, in groups of five, 1 h and 14, 30, 60, 90 and 120 days after injection. The displacement of labelled adrenocytes with time was estimated in autoradiograms of adrenal sections. The radial distance of the labelled cell from the capsule was measured with an eyepiece micrometer and expressed in cell location units, i.e. the number of cells separating the labelled cell from the capsule. One hour after labelling, 95% of labelled cells were confined to the outer quarter of the cortex. During the following days, adrenocytes were displaced inwardly, approaching the medulla at a velocity of 0·24 locations/day. They traversed the three cortex zones, reaching the medulla after 104 days. The three adrenal zones represent three differentiation states of the adrenocyte. When young, the adrenocyte secretes aldosterone, after leaving the glomerulosa it produces corticosteroids and on reaching the reticularis it produces sex hormones. The adrenal cortex is a cell renewal system made of two compartments. A progenitor compartment extending between locations 1 and 15, and a functional compartment, covering locations 16–64. The first compartment produces 0·47 cells daily, which enter the second. Half of them die on their way while the rest are eliminated in the reticular zone. The cell stream is nourished by a subcapsular stem cell. J. Endocr. (1986) 111, 477–482

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Rabinowitz, S., H. Horstmann, S. Gordon e G. Griffiths. "Immunocytochemical characterization of the endocytic and phagolysosomal compartments in peritoneal macrophages." Journal of Cell Biology 116, n.º 1 (1 de janeiro de 1992): 95–112. http://dx.doi.org/10.1083/jcb.116.1.95.

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We have used endocytic and phagocytic tracers in an EM immunocytochemical study to define the compartments of the phagocytic and endocytic pathways in mouse peritoneal macrophages. Endocytosed BSA-gold appeared successively in early endosomes, spherical endosomal vesicles, a late endosomal tubuloreticular compartment (TC), and terminal lysosomes. The TC appeared as an elaborate structure enriched for the lysosomal membrane glycoproteins Lamp 1 and Lamp 2, and expressing significant levels of rab7, a late endosome-specific GTP-binding protein. The cation-independent mannose-6-phosphate receptor was restricted to specialized regions of the TC that were predominantly adjacent to the Golgi complex. Both the early endosome and the TC had coated bud structures whose composition and function are presently unknown. Phagolysosomes containing latex beads expressed the same membrane antigens and received endocytic tracers simultaneously with the TC. Since the membrane surrounding both organelles was also in direct continuity, we assume that both structures form one functional compartment. Macrosialin, an antigen confined to macrophages and dendritic cells, was heavily expressed in TC and phagolysosomal membranes with low levels being detected in other endosomal compartments and on the cell surface. Treatment of cells with wheat germ agglutinin drastically altered the morphology of the TC, giving rise to sheets of tightly adherent membrane and greatly expanded vesicles, in which cell-associated wheat germ agglutinin was concentrated. The spherical endosomal carrier vesicles loaded with internalized gold tracers clustered nearby, often making contact without fusing. Since the delivery of endocytic tracer to the TC was significantly delayed these experiments suggest that the lectin is somehow preventing the endosome vesicles from fusing with the TC. Collectively, our data argue first that the PLC is equivalent to the "tubular lysosomes" commonly described in macrophages, and second that the meeting of the phagocytic and endocytic pathway occurs in this compartment.

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Wang, Xiao Wei, Hai Bing Hu, Jun Qin e Yong Ming Zhang. "A New Method to Detect Fire and Alarm in Confined Space Based on Electronic Nose". Applied Mechanics and Materials 390 (agosto de 2013): 383–87. http://dx.doi.org/10.4028/www.scientific.net/amm.390.383.

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This paper presents a new method to detect fire and alarm in confined space based on electronic nose. Common confined space includes some distribution cabinet, machine room, warehouse, air cargo compartment and spacecraft cabin, etc. Combined with the characteristics of the confined space, a fire detection and alarm system is schematically designed. This system is based on electronic nose and is an aspirated configuration. With this system, this method adopts PNN as the recognition algorithm, and introduces steady status and warning time to the monitoring host. The CO, O2, CO2and temperature are taken into account as the input of the PNN to get the probability of fire. Compared with the normal methods, this method can detect fire more quickly, reduce the false and missing alarm rate and realize real-time online alarming.

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Pretrel, Hugues, e Laurent Audouin. "Periodic puffing instabilities of buoyant large-scale pool fires in a confined compartment". Journal of Fire Sciences 31, n.º 3 (16 de novembro de 2012): 197–210. http://dx.doi.org/10.1177/0734904112462361.

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Seidenbecher, Constanze I., Kristina Langnaese, Lydia Sanmartı́-Vila, Tobias M. Boeckers, Karl-Heinz Smalla, Bernhard A. Sabel, Craig C. Garner, Eckart D. Gundelfinger e Michael R. Kreutz. "Caldendrin, a Novel Neuronal Calcium-binding Protein Confined to the Somato-dendritic Compartment". Journal of Biological Chemistry 273, n.º 33 (14 de agosto de 1998): 21324–31. http://dx.doi.org/10.1074/jbc.273.33.21324.

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Chen, Xiao, Shouxiang Lu, Xiaomin Wang, Kim Meow Liew, Changhai Li e Jiaqing Zhang. "Pulsation Behavior of Pool Fires in a Confined Compartment with a Horizontal Opening". Fire Technology 52, n.º 2 (23 de maio de 2015): 515–31. http://dx.doi.org/10.1007/s10694-015-0484-z.

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Gantert, Markus, Reint K. Jellema, Heike Heineman, Julia Gantert, Jennifer J. P. Collins, Matthias Seehase, Verena A. C. Lambermont et al. "Lipopolysaccharide-Induced Chorioamnionitis Is Confined to One Amniotic Compartment in Twin Pregnant Sheep". Neonatology 102, n.º 2 (2012): 81–88. http://dx.doi.org/10.1159/000338015.

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Butler, C., e D. Newport. "Experimental and numerical analysis of thermally dissipating equipment in an aircraft confined compartment". Applied Thermal Engineering 73, n.º 1 (dezembro de 2014): 869–78. http://dx.doi.org/10.1016/j.applthermaleng.2014.08.035.

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Deenen, G. J., S. V. Hunt e D. Opstelten. "A stathmokinetic study of B lymphocytopoiesis in rat bone marrow: proliferation of cells containing cytoplasmic mu-chains, terminal deoxynucleotidyl transferase and carrying HIS24 antigen." Journal of Immunology 139, n.º 3 (1 de agosto de 1987): 702–10. http://dx.doi.org/10.4049/jimmunol.139.3.702.

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Abstract In rat bone marrow (BM), the B lineage surface antigen HIS24 is expressed by all surface mu chain-bearing (s mu+) B cells, by cytoplasmic mu chain-containing (c mu+s mu-) pre-B cells and TdT+ cells, and by lymphoid cells lacking both mu and TdT. Because TdT+ and HIS24+TdT-mu- cells may represent stages in B lymphocytopoiesis before mu chain expression, we investigated their kinetics. The metaphase arrest method was combined with immunofluorescence staining to detect proliferation and to quantitate cell production in the BM pre-B, TdT+, and HIS24+TdT-mu- compartments. Their apparent cell cycle times (tC(a)) were 38, 36, and 19 hr, and the number of cells produced per hour per femur were 58, 9, and 41 X 10(4), respectively. The HIS24+ compartments showed further phenotypic heterogeneity. Six percent of TdT+ cells expressed mu chains and were therefore pre-B cells. Twenty percent of HIS24+TdT-mu- cells expressed Ig other than mu chains, with size distribution and kinetics similar to HIS24+TdT-Ig- cells. Thus, the rate of production in the truly Ig-HIS24+ compartment was about 40 X 10(4)/hr/femur (8.5 by TdT+mu- and 33 by TdT-Ig-). In each phenotypic compartment, mitoses were confined to subsets of large (greater than 11 to 12 micron) cells with tC(a) of 13 to 15 hr. Surface mu+ B cells were essentially non-cycling. To quantitate whole body BM cell production, the recovery of marrow from bone and the distribution of BM were measured in 59Fe distribution experiments. The number of cells produced by whole body BM was estimated as follows: for pre-B cells, 4.5 X 10(8)/day; for TdT+mu-, 0.7 X 10(8)/day; and for HIS24+TdT-Ig- 2.6 X 10(8)/day. From the derived cell flux in these compartments we suggest that 1) many more pre-B cells are produced than needed by the peripheral B cell pool; 2) if TdT is an obligatory stage in B cell genesis, there must be at least two cell cycles in the pre-B cell compartment; 3) if it is not, the TdT+ stage may be bypassed, with HIS24+TdT-Ig- cells perhaps feeding directly into the pre-B cell compartment.

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Cammann, Jan, Fabian Jan Schwarzendahl, Tanya Ostapenko, Danylo Lavrentovich, Oliver Bäumchen e Marco G. Mazza. "Emergent probability fluxes in confined microbial navigation". Proceedings of the National Academy of Sciences 118, n.º 39 (23 de setembro de 2021): e2024752118. http://dx.doi.org/10.1073/pnas.2024752118.

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When the motion of a motile cell is observed closely, it appears erratic, and yet the combination of nonequilibrium forces and surfaces can produce striking examples of organization in microbial systems. While most of our current understanding is based on bulk systems or idealized geometries, it remains elusive how and at which length scale self-organization emerges in complex geometries. Here, using experiments and analytical and numerical calculations, we study the motion of motile cells under controlled microfluidic conditions and demonstrate that probability flux loops organize active motion, even at the level of a single cell exploring an isolated compartment of nontrivial geometry. By accounting for the interplay of activity and interfacial forces, we find that the boundary’s curvature determines the nonequilibrium probability fluxes of the motion. We theoretically predict a universal relation between fluxes and global geometric properties that is directly confirmed by experiments. Our findings open the possibility to decipher the most probable trajectories of motile cells and may enable the design of geometries guiding their time-averaged motion.

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Altabef, M., J. D. Clarke e C. Tickle. "Dorso-ventral ectodermal compartments and origin of apical ectodermal ridge in developing chick limb". Development 124, n.º 22 (15 de novembro de 1997): 4547–56. http://dx.doi.org/10.1242/dev.124.22.4547.

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We wish to understand how limbs are positioned with respect to the dorso-ventral axis of the body in vertebrate embryos, and how different regions of limb bud ectoderm, i.e. dorsal ectoderm, apical ridge and ventral ectoderm, originate. Signals from dorsal and ventral ectoderm control dorso-ventral patterning while the apical ectodermal ridge (AER) controls bud outgrowth and patterning along the proximo-distal axis. We show, using cell-fate tracers, the existence of two distinct ectodermal compartments, dorsal versus ventral, in both presumptive limb and flank of early chick embryos. This organisation of limb ectoderm is the first direct evidence, in vertebrates, of compartments in non-neural ectoderm. Since the apical ridge appears to be confined to this compartment boundary, this positions the limb. The mesoderm, unlike the ectoderm, does not contain two separate dorsal and ventral cell lineages, suggesting that dorsal and ventral ectoderm compartments may be important to ensure appropriate control of mesodermal cell fate. Surprisingly, we also show that cells which form the apical ridge are initially scattered in a wide region of early ectoderm and that both dorsal and ventral ectoderm cells contribute to the apical ridge, intermingling to some extent within it.

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Calef, Richard S., Michael C. Choban, Katherine R. Glenney, Ruth A. Calef, Julie N. Godbey e Ila M. Hislrman. "Delay of Reinforcement Effects: Timing of Reinforcement or Narrow Goal-Box Confinement". Psychological Reports 87, n.º 3 (dezembro de 2000): 988–90. http://dx.doi.org/10.2466/pr0.2000.87.3.988.

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The present experiment investigated whether narrow goal-box confinement in studies of delay of reinforcement in the runway may have had aversive or punishing effects. Analysis showed no difference in performance between groups of rats who were either confined in a narrow goal-box or a large compartment while receiving their delay of reinforcement. The results suggest that narrow goal-box confinement does not have aversive characteristics.

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Dong, Qiwei, Yanfeng Li, Junmei Li, Fei Xie, Desheng Xu e Zhihe Su. "The Influence of Confined Space Size on the Temperature Distribution Characteristics of Internal Window Plume from Well-Ventilated Compartment Fires". Fire 7, n.º 5 (1 de maio de 2024): 158. http://dx.doi.org/10.3390/fire7050158.

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In this research, the influence of confined space size on the temperature distribution characteristics of internal window plumes from well-ventilated compartment fires was studied. Theoretical analysis was firstly used to establish a mathematical model for the smoke after ejecting from the window in the space. The study considered fire heat release rate and vertical height as dependent variables. Numerical simulations and experimental methods were carried out to study the temperature variations. A critical distance L2 was obtained. Results show that when the space D between the vertical retaining wall and the building façade is greater than L2, the variation of D has little influence on radial temperature. Once D is less than L2, the radial temperature distribution inside the confined space will tend to be consistent, and the temperature in the confined space sharply increases as D decreases. In addition, a dimensionless model was derived to quantify the relationship between temperature rise and vertical height. The experimental and numerical simulation results were processed, which are in good agreement with the model. The study can provide a framework for managing building safety.

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Huang, Xianjia, Zhaoying Ren, He Zhu, Lan Peng, Chihonn Cheng e Wanki Chow. "A modified zone model on vertical cable tray fire in a confined compartment in the nuclear power plant". Journal of Fire Sciences 36, n.º 6 (19 de setembro de 2018): 472–93. http://dx.doi.org/10.1177/0734904118800648.

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Room fire with vertical cable tray involves upward flame spread along the cable. Assessing the vertical cable tray fire hazard in confined spaces has been challenging because of the strong coupling between flame spread and heat transfer. Long computing time is required in using sophisticated field model with computational fluid dynamics. Therefore, developing an appropriate zone model in a cable room fire with experimental validation is required for engineering applications. In this study, a vertical cable tray fire in a confined compartment was simulated using a modified zone model along three new areas on having temporal variations of the fire position, upward-spreading cable flame considered as a burning source moving at a constant speed, and validated through full-scale experiments on vertical cable tray fire with two typical cable-line spacing. The modified zone model can predict accurately the upper-layer temperature in the compartment. The accuracy is at least 25% higher than the model with fixed fire position. The measured temperature at different heights started to decrease at different times, which was due to the vertical spreading of the cable flame. For interface height, the relative error and normalized Euclidean distance in the time-varying fire position model can be improved by 50%.

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Mayer, Gaétan, e Moïse Bendayan. "Biotinyl–Tyramide: A Novel Approach for Electron Microscopic Immunocytochemistry". Journal of Histochemistry & Cytochemistry 45, n.º 11 (novembro de 1997): 1449–54. http://dx.doi.org/10.1177/002215549704501101.

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The biotinyl–tyramide protocol recently introduced for sensitive light microscopic immunocytochemistry was applied to electron microscopy and revealed various tissue antigens with high resolution. The protocol consists of an indirect method in which thin tissue sections are incubated successively within a specific primary antibody, followed by a biotinylated secondary antibody, streptavidin–HRP, and then finally with biotinyl–tyramide. The reaction product appears as a dense filamentous material that is deposited over particular cellular compartments. The labeling obtained for the antigens tested, amylase and heat-shock protein 70 in pancreatic acinar cells, insulin in pancreatic β-cells, and carbamoyl phosphate synthetase and catalase in liver tissue, was found to be highly specific, with the labeling for each antigen confined to its particular cellular compartment. Background levels and nonspecific deposition of the staining were negligible. The use of biotinyl–tyramide therefore appears to be an alternative sensitive technique for immunoelectron microscopy. (J Histochem Cytochem 45:1449–1454, 1997)

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38

Sadoni, Nicolas, Sabine Langer, Christine Fauth, Giorgio Bernardi, Thomas Cremer, Bryan M. Turner e Daniele Zink. "Nuclear Organization of Mammalian Genomes". Journal of Cell Biology 146, n.º 6 (20 de setembro de 1999): 1211–26. http://dx.doi.org/10.1083/jcb.146.6.1211.

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We investigated the nuclear higher order compartmentalization of chromatin according to its replication timing (Ferreira et al. 1997) and the relations of this compartmentalization to chromosome structure and the spatial organization of transcription. Our aim was to provide a comprehensive and integrated view on the relations between chromosome structure and functional nuclear architecture. Using different mammalian cell types, we show that distinct higher order compartments whose DNA displays a specific replication timing are stably maintained during all interphase stages. The organizational principle is clonally inherited. We directly demonstrate the presence of polar chromosome territories that align to build up higher order compartments, as previously suggested (Ferreira et al. 1997). Polar chromosome territories display a specific orientation of early and late replicating subregions that correspond to R- or G/C-bands of mitotic chromosomes. Higher order compartments containing G/C-bands replicating during the second half of the S phase display no transcriptional activity detectable by BrUTP pulse labeling and show no evidence of transcriptional competence. Transcriptionally competent and active chromatin is confined to a coherent compartment within the nuclear interior that comprises early replicating R-band sequences. As a whole, the data provide an integrated view on chromosome structure, nuclear higher order compartmentalization, and their relation to the spatial organization of functional nuclear processes.

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Bagnato, Giulia, Martina Leopizzi, Enrica Urciuoli e Barbara Peruzzi. "Nuclear Functions of the Tyrosine Kinase Src". International Journal of Molecular Sciences 21, n.º 8 (11 de abril de 2020): 2675. http://dx.doi.org/10.3390/ijms21082675.

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Src is the representative member of the Src-family kinases (SFKs), a group of tyrosine kinases involved in several cellular processes. Its main function has been for long confined to the plasma membrane/cytoplasm compartment, being a myristoylated protein anchored to the cell membrane and functioning downstream to receptors, most of them lacking intrinsic kinase activity. In the last decades, new roles for some SFKs have been described in the nuclear compartment, suggesting that these proteins can also be involved in directly regulating gene transcription or nucleoskeleton architecture. In this review, we focused on those nuclear functions specifically attributable to Src, by considering its function as both tyrosine kinase and adapting molecule. In particular, we addressed the Src involvement in physiological as well as in pathological conditions, especially in tumors.

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40

Prétrel, H., W. Le Saux e L. Audouin. "Pressure variations induced by a pool fire in a well-confined and force-ventilated compartment". Fire Safety Journal 52 (agosto de 2012): 11–24. http://dx.doi.org/10.1016/j.firesaf.2012.04.005.

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Pol, Erwan, Etienne Côme, Zaha Merlaud, Juliette Gouhier, Marion Russeau, Sophie Scotto-Lomassese, Imane Moutkine, Xavier Marques e Sabine Lévi. "NKCC1 and KCC2 Chloride Transporters Have Different Membrane Dynamics on the Surface of Hippocampal Neurons". Cells 12, n.º 19 (26 de setembro de 2023): 2363. http://dx.doi.org/10.3390/cells12192363.

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Na-K-2Cl cotransporter 1 (NKCC1) regulates chloride influx in neurons and thereby GABAA receptor activity in normal and pathological conditions. Here, we characterized in hippocampal neurons the membrane expression, distribution and dynamics of exogenous NKCC1a and NKCC1b isoforms and compared them to those of the chloride extruder K-Cl cotransporter 2 (KCC2). We found that NKCC1a and NKCC1b behave quite similarly. NKCC1a/1b but not KCC2 are present along the axon initial segment where they are confined. Moreover, NKCC1a/1b are detected in the somato-dendritic compartment at a lower level than KCC2, where they form fewer, smaller and less compact clusters at perisynaptic and extrasynaptic sites. Interestingly, ~60% of dendritic clusters of NKCC1a/1b are colocalized with KCC2. They are larger and brighter than those devoid of KCC2, suggesting a particular NKCC1a/1b-KCC2 relationship. In agreement with the reduced dendritic clustering of NKCC1a/1b compared with that of KCC2, NKCC1a/1b are more mobile on the dendrite than KCC2, suggesting weaker cytoskeletal interaction. NKCC1a/b are confined to endocytic zones, where they spend more time than KCC2. However, they spend less time in these compartments than at the synapses, suggesting that they can rapidly leave endocytic zones to increase the membrane pool, which can happen in pathological conditions. Thus, NKCC1a/b have different membrane dynamics and clustering from KCC2, which helps to explain their low level in the neuronal membrane, while allowing a rapid increase in the membrane pool under pathological conditions.

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Ritzenthaler, C., C. Laporte, F. Gaire, P. Dunoyer, C. Schmitt, S. Duval, A. Piéquet et al. "Grapevine Fanleaf Virus Replication Occurs on Endoplasmic Reticulum-Derived Membranes". Journal of Virology 76, n.º 17 (1 de setembro de 2002): 8808–19. http://dx.doi.org/10.1128/jvi.76.17.8808-8819.2002.

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ABSTRACT Infection by Grapevine fanleaf nepovirus (GFLV), a bipartite RNA virus of positive polarity belonging to the Comoviridae family, causes extensive cytopathic modifications of the host endomembrane system that eventually culminate in the formation of a perinuclear “viral compartment.” We identified by immunoconfocal microscopy this compartment as the site of virus replication since it contained the RNA1-encoded proteins necessary for replication, newly synthesized viral RNA, and double-stranded replicative forms. In addition, by using transgenic T-BY2 protoplasts expressing green fluorescent protein in the endoplasmic reticulum (ER) or in the Golgi apparatus (GA), we could directly show that GFLV replication induced a depletion of the cortical ER, together with a condensation and redistribution of ER-derived membranes, to generate the viral compartment. Brefeldin A, a drug known to inhibit vesicle trafficking between the GA and the ER, was found to inhibit GFLV replication. Cerulenin, a drug inhibiting de novo synthesis of phospholipids, also inhibited GFLV replication. These observations imply that GFLV replication depends both on ER-derived membrane recruitment and on de novo lipid synthesis. In contrast to proteins involved in viral replication, the 2B movement protein and, to a lesser extent, the 2C coat protein were not confined to the viral compartment but were transported toward the cell periphery, a finding consistent with their role in cell-to-cell movement of virus particles.

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Sako, Y., e A. Kusumi. "Barriers for lateral diffusion of transferrin receptor in the plasma membrane as characterized by receptor dragging by laser tweezers: fence versus tether." Journal of Cell Biology 129, n.º 6 (15 de junho de 1995): 1559–74. http://dx.doi.org/10.1083/jcb.129.6.1559.

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Our previous results indicated that the plasma membrane of cultured normal rat kidney fibroblastic cell is compartmentalized for diffusion of receptor molecules, and that long-range diffusion is the result of successive intercompartmental jumps (Sako, Y. and Kusumi, A. 1994. J. Cell Biol. 125:1251-1264). In the present study, we characterized the properties of intercompartmental boundaries by tagging transferrin receptor (TR) with either 210-nm-phi latex or 40-nm-phi colloidal gold particles, and by dragging the particle-TR complexes laterally along the plasma membrane using laser tweezers. Approximately 90% of the TR-particle complexes showed confined-type diffusion with a microscopic diffusion coefficient (Dmicro) of approximately 10(-9) cm2/s and could be dragged past the intercompartmental boundaries in their path by laser tweezers at a trapping force of 0.25 pN for gold-tagged TR and 0.8 pN for latex-tagged TR. At lower dragging forces between 0.05 and 0.1 pN, particle-TR complexes tended to escape from the laser trap at the boundaries, and such escape occurred in both the forward and backward directions of dragging. The average distance dragged was half of the confined distance of TR, which further indicates that particle-TR complexes escape at the compartment boundaries. Since variation in the particle size (40 and 210 nm, the particles are on the extracellular surface of the plasma membrane) hardly affects the diffusion rate and behavior of the particle-TR complexes at the compartment boundaries, and since treatment with cytochalasin D or vinblastin affects the movements of TR (Sako and Kusumi as cited above), argument has been advanced that the boundaries are present in the cytoplasmic domain. Rebound of the particle-TR complexes when they escape from the laser tweezers at the compartment boundaries suggests that the boundaries are elastic structures. These results are consistent with the proposal that the compartment boundaries consist of membrane skeleton or a membrane-associated part of the cytoskeleton (membrane skeleton fence model). Approximately 10% of TR exhibited slower diffusion (Dmicro approximately 10(-10)-10(-11) cm2/s) and binding to elastic structures.

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Fujiwara, Takahiro K., Kokoro Iwasawa, Ziya Kalay, Taka A. Tsunoyama, Yusuke Watanabe, Yasuhiro M. Umemura, Hideji Murakoshi et al. "Confined diffusion of transmembrane proteins and lipids induced by the same actin meshwork lining the plasma membrane". Molecular Biology of the Cell 27, n.º 7 (abril de 2016): 1101–19. http://dx.doi.org/10.1091/mbc.e15-04-0186.

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The mechanisms by which the diffusion rate in the plasma membrane (PM) is regulated remain unresolved, despite their importance in spatially regulating the reaction rates in the PM. Proposed models include entrapment in nanoscale noncontiguous domains found in PtK2 cells, slow diffusion due to crowding, and actin-induced compartmentalization. Here, by applying single-particle tracking at high time resolutions, mainly to the PtK2-cell PM, we found confined diffusion plus hop movements (termed “hop diffusion”) for both a nonraft phospholipid and a transmembrane protein, transferrin receptor, and equal compartment sizes for these two molecules in all five of the cell lines used here (actual sizes were cell dependent), even after treatment with actin-modulating drugs. The cross-section size and the cytoplasmic domain size both affected the hop frequency. Electron tomography identified the actin-based membrane skeleton (MSK) located within 8.8 nm from the PM cytoplasmic surface of PtK2 cells and demonstrated that the MSK mesh size was the same as the compartment size for PM molecular diffusion. The extracellular matrix and extracellular domains of membrane proteins were not involved in hop diffusion. These results support a model of anchored TM-protein pickets lining actin-based MSK as a major mechanism for regulating diffusion.

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Podkowinski, Dominika, Ana-Maria Philip, Wolf-Dieter Vogl, Jutta Gamper, Hrvoje Bogunovic, Bianca S. Gerendas, Bilal Haj Najeeb, Sebastian M. Waldstein e Ursula Schmidt-Erfurth. "Neuroretinal atrophy following resolution of macular oedema in retinal vein occlusion". British Journal of Ophthalmology 103, n.º 1 (6 de março de 2018): 36–42. http://dx.doi.org/10.1136/bjophthalmol-2017-311614.

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Background/aimsTo characterise neuroretinal atrophy in retinal vein occlusion (RVO).MethodsWe included patients with central/branch RVO (CRVO=196, BRVO=107) who received ranibizumab according to a standardised protocol for 6 months. Retinal atrophy was defined as the presence of an area of retinal thickness (RT) <260 µm outside the foveal centre. Moreover, the thickness of three distinct retinal layer compartments was computed as follows: (1) retinal nerve fibre layer to ganglion cell layer, (2) inner plexiform layer (IPL) to outer nuclear layer (ONL) and (3) inner segment/outer segment junction to retinal pigment epithelium. To characterise atrophy further, we assessed perfusion status on fluorescein angiography and best-corrected visual acuity (BCVA), and compared these between eyes with/without atrophy.Results23 patients with CRVO and 11 patients with BRVO demonstrated retinal atrophy, presenting as sharply demarcated retinal thinning confined to a macular quadrant. The mean RT in the atrophic quadrant at month 6 was 249±26 µm (CRVO) and 244±29 µm (BRVO). Individual layer analysis revealed pronounced thinning in the IPL to ONL compartment. Change in BCVA at 6 months was similar between the groups (BRVO, +15 vs +18 letters; CRVO, +14 vs +18 letters).ConclusionsIn this exploratory analysis, we describe the characteristics of neuroretinal atrophy in RVO eyes with resolved macular oedema after ranibizumab therapy. Our analysis shows significant, predominantly retinal thinning in the IPL to ONL compartment in focal macular areas in 11% of patients with RVO. Eyes with retinal atrophy did not show poorer BCVA outcomes.

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Le, Duy, Jeffrey Labahn, Tarek Beji, Cecile B. Devaud, Elizabeth J. Weckman e Abderrazzaq Bounagui. "Assessment of the capabilities of FireFOAM to model large-scale fires in a well-confined and mechanically ventilated multi-compartment structure". Journal of Fire Sciences 36, n.º 1 (24 de outubro de 2017): 3–29. http://dx.doi.org/10.1177/0734904117733427.

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This article presents a large eddy simulation study of a pool fire in a well-confined and mechanically ventilated multi-room configuration. The capabilities of FireFOAM are assessed by comparing the numerical results to a well-documented set of experimental data available from Propagation d’un Incendie pour des Scénarios Multi-locaux Elémentaires. The eddy dissipation concept, finite volume discrete ordinate method, and one k-equation model are used for combustion, thermal radiation, and sub-grid scale closure, respectively. The main boundary conditions are imposed based on the experimental profiles. A detailed comparison is made with available experimental data. Good agreement between the large eddy simulation results and experimental values is achieved for temperatures, velocity, CO2 volume concentrations, and pressures for most compartments. There are some noticeable underpredictions of temperature in the outlet room. Overall, FireFOAM is shown to have good predictive capabilities for the present confined large-scale fire scenario.

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Abd-ElHady, Mohamed Elsayed, Imane Yassine, Ehab Ahmed Hashish, Maha Mohamed Anani e Mohamed Ibraheem Negm. "Role of Neurofilament Light Chain as A Biomarker in Neurological Disorders: A Literature Review". SVOA Neurology 4, n.º 4 (10 de julho de 2023): 98–102. http://dx.doi.org/10.58624/svoane.2023.04.099.

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Neurofilament light chain (NfL) is a main element of neurons’ structure which is exclusively confined to the neuroaxonal compartment, NfL therefore provides an advantage over other potential biomarkers since it’s highly selective for neuronal cell injury and eventual neuronal cell death. Independent of etiology, NfL levels in CSF and blood increase above normal in response to neuronal damage and neurodegeneration, making it a suitable candidate as a biomarker in these circumstances. Biomarkers of neuronal injury and neurodegeneration have the potential to enhance diagnostic accuracy, disease monitoring, and prognosis.

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Sako, Y., e A. Kusumi. "Compartmentalized structure of the plasma membrane for receptor movements as revealed by a nanometer-level motion analysis." Journal of Cell Biology 125, n.º 6 (15 de junho de 1994): 1251–64. http://dx.doi.org/10.1083/jcb.125.6.1251.

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Movements of transferrin and alpha 2-macroglobulin receptor molecules in the plasma membrane of cultured normal rat kidney (NRK) fibroblastic cells were investigated by video-enhanced contrast optical microscopy with 1.8 nm spatial precision and 33 ms temporal resolution by labeling the receptors with the ligand-coated nanometer-sized colloidal gold particles. For both receptor species, most of the movement trajectories are of the confined diffusion type, within domains of approximately 0.25 microns2 (500-700 nm in diagonal length). Movement within the domains is random with a diffusion coefficient approximately 10(-9) cm2/s, which is consistent with that expected for free Brownian diffusion of proteins in the plasma membrane. The receptor molecules move from one domain to one of the adjacent domains at an average frequency of 0.034 s-1 (the residence time within a domain approximately 29 s), indicating that the plasma membrane is compartmentalized for diffusion of membrane receptors and that long-range diffusion is the result of successive intercompartmental jumps. The macroscopic diffusion coefficients for these two receptor molecules calculated on the basis of the compartment size and the intercompartmental jump rate are approximately 2.4 x 10(-11) cm2/s, which is consistent with those determined by averaging the long-term movements of many particles. Partial destruction of the cytoskeleton decreased the confined diffusion mode, increased the simple diffusion mode, and induced the directed diffusion (transport) mode. These results suggest that the boundaries between compartments are made of dynamically fluctuating membrane skeletons (membrane-skeleton fence model).

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Mutterer, J. D., C. Stussi-Garaud, P. Michler, K. E. Richards, G. Jonard e V. Ziegler-Graff. "Role of the beet western yellows virus readthrough protein in virus movement in Nicotiana clevelandii". Journal of General Virology 80, n.º 10 (1 de outubro de 1999): 2771–78. http://dx.doi.org/10.1099/0022-1317-80-10-2771.

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Luteoviruses such as beet western yellows polerovirus (BWYV) are confined to and multiply within the phloem compartment of their hosts. The readthrough domain (RTD) of the minor BWYV capsid protein P74 is required for efficient virus accumulation in Nicotiana clevelandii. Experiments were carried out to determine if the low virus titres observed following agro-inoculation of whole plants with certain RTD mutants are due to a defect in virus multiplication in the nucleate cells of the phloem compartment or to inefficient virus movement to new infection sites. Immuno-localization of wild-type and an RTD-null mutant virus in thin sections of petioles and in phloem cells of leaf lamina, as well as electron microscopy observations, were all consistent with the conclusion that the RTD is not essential for efficient virus multiplication in the nucleate phloem cells but intervenes in virus movement to increase the rate at which new infection foci are established and expand.

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Ilyin, L. A., O. A. Kochetkov, A. V. Barabanova e V. G. Barchukov. "Health Effects of Onboard Radiation Accidents in the Soviet Nuclear Submarines". MEDICAL RADIOLOGY AND RADIATION SAFETY 68, n.º 6 (dezembro de 2023): 42–48. http://dx.doi.org/10.33266/1024-6177-2023-68-6-42-48.

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Purpose: To analyze the health effects of onboard radiation accidents in the Soviet nuclear submarines. Results: Over the entire operation period of Soviet nuclear submarines, eight severe accidents occurred related to nuclear power installations. These accidents occurred in a confined space and the associated radiation situation is more complex than in other conditions; therefore, health effects of such accidents are more significant. There were two types of onboard accidents: thermal accidents (five cases) associated with a failure during heat removal from the reactor core; and accidents (three cases) caused by a partial chain reaction. The first type of accidents occurred during the route operation of nuclear submarine, and the second one – during repair work. Thermal accidents were associated with varying degrees of depressurization of the primary circuit of the reactor, which increased the gamma and beta background due to the entry into the compartment of a large amount of radioactive noble gases (hereinafter – RBGs) and radioactive aerosols. It has been shown that in the confined space of nuclear submarines, RBG isotopes (mainly 85Кr, 133Хе, 135Хе) make a significant contribution to the individual dose and the skin is a critical organ. Conclusion: An analysis of the health effects of thermal onboard accidents showed that radiation injuries were caused by external gamma- and beta-exposure, as well as the ingestion of radioactive aerosols. If accidents are accompanied by prolonged minor leaks leading to entry of RBG into the compartment, the main contribution is made by beta-exposure and the skin is a critical organ. If there is a simultaneous inflow of coolant into the compartment, combined radiation injuries are formed and, in this case, skin lesions aggravate the acute radiation sickness. In accidents induced by a partial chain reaction, the main radiation factor is external γ-n-exposure during an outbreak of a partial chain reaction, and in the case of a thermal explosion, a traumatic factor also affects a person, leading to injuries of varying severity in the victims.

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