Dissertations / Theses on the topic 'Breastfeeding Effect of drugs on'

Breastfeeding self-efficacy is considered one of the key components of a successful breastfeeding experience. The benefits of breastfeeding are well established in the literature and have been widely communicated to the public, resulting in an increasing trend of breastfeeding initiation. However, the United States still falls short of Healthy People 2020 breastfeeding goals. The purpose of this project was to examine the effects of a standardized hospital-based prenatal breastfeeding class on breastfeeding self-efficacy. Dennis's breastfeeding self-efficacy theory was the foundation for the breastfeeding self-efficacy tool used in this project. A quasi-experimental design used a convenience sample of 30 breastfeeding class participants as the experimental group and 30 postpartum women who had no formal breastfeeding education as the control group. The Breastfeeding Self-Efficacy Scale Short Form (BSES-SF) was administered to the intervention group prior to the breastfeeding class, at the end of the class, prior to hospital discharge, and at 2 weeks postpartum. The control group received the survey prior to hospital discharge and at 2 weeks postpartum. Key findings indicated that participants in the breastfeeding class demonstrated a statistically significant increase in breastfeeding confidence after the class (t = 9.55(29), p = 0.00). There was no difference between the intervention and control groups at discharge (t = -.412(47), p = 0.686). Nurses and lactation professionals are in a position to evoke social change by examining the impact of breastfeeding self-efficacy and using the findings to shape breastfeeding education.

The purpose of this study was to examine the effect of a breastfeeding education program on breastfeeding initiation rates, breastfeeding knowledge, and attitude towards breastfeeding among teenage mothers at an urban school for pregnant and parenting teens. Breastfeeding initiation rose from 35.7% in the control group to 85.2% in the treatment group. The mean score on the Breastfeeding Knowledge Subscale was significantly higher for the treatment group but not the control group. There was not a significant increase in mean scores on the Breastfeeding Attitude Subscale. Participants who initiated breastfeeding scored also had a significant increase in scores from pretest to posttest on the Breastfeeding Knowledge Subscale, while participants who did not initiate breastfeeding did not.

This thesis describes the development of a curriculum for a prenatal breastfeeding workshop and the randomized controlled trial that was completed to test the hypotheses that the workshop would have a positive influence on maternal breastfeeding self-efficacy and that increased self-efficacy would positively affect breastfeeding duration. Breastfeeding self-efficacy, measured with the Breastfeeding Self-Efficacy Scale-Short Form, and breastfeeding duration, recorded as number of days and amount of breastfeeding, were measured at 4 and 8 weeks postpartum. The results of this study suggest that the prenatal breastfeeding workshop had a positive effect on maternal breastfeeding self-efficacy and on the amount women were breastfeeding. Over time, maternal breastfeeding self-efficacy scores increased in both groups with the intervention group having higher scores. At week 4, there was a significant difference in scores (control, M = 53.38 (SD = 9.1); intervention, M = 57.98 (SD = 8.6), t(78) = -2.32, p = .023, d = .523, CI -8.53, -0.65) At week 8, there was a difference in scores, but given the small sample size, these were not statistically significant (control, M = 58.91 (SD = 9.1); intervention, M = 61.70 (SD = 5.8), t(72) = -1.60, p = .115, d = .412). Although there was little difference between the groups in the number of days of breastfeeding, the intervention group had more exclusive breastfeeding (70% vs. 58%) and less weaning (15% vs. 22%) when compared with the control group. The most common reason for weaning was insufficient milk supply. (Abstract shortened by UMI.)

Breastfeeding has health benefits for mother and child, allowing a mother to protect her newborn from numerous infections while promoting healthy nutrition and growth. Breastfed babies have decreased risk of later negative health problems including respiratory infection, asthma, obesity, and Type II diabetes. The minimum acceptable time a mother should breastfeed is six weeks, but major healthcare organizations, such as the American Academy of Pediatrics, recommend exclusive breastfeeding for the first six months of life. Nationally, 43.1% of babies were exclusively breastfed the first six weeks in 2009, and rates in rural Appalachia are known to be significantly lower than national averages. Researchers have found factors such as age, socioeconomic, marital, and smoking statuses to be predictive of breastfeeding continuation, but maternal innate characteristics have not been explored extensively. To clarify why a mother chooses to breastfeed or not, it is important to additionally look at intrinsic characteristics such as temperament. Temperament is an individual’s biologically based ability to think, behave, and react. Effortful control, a specific component of temperament, is the voluntary regulation of emotions and behaviors. The current study examined the impact of effortful control on participants’ likelihood of breastfeeding at six weeks postpartum. Informationwas collected from pregnant women recruited from Northeast Tennessee as part of the Tennessee Intervention for Pregnant Smokers Program. As part of the larger study, women completed detailed research interviews multiple times during pregnancy, and at six weeks post-partum. The responses of interest came from 230 women who had complete demographic questionnaire, Adult Temperament Questionnaire (ATQ), delivery and birth chart information, and six-week interview breastfeeding status. Logistic regression was used to assess the impact of maternal effortful control (subscale of the ATQ) on the mother’s decision to exclusively breastfeed the child up to six weeks postpartum. The model contained five variables that were significantly correlated with the breastfeeding continuation: maternal age, birth weight (normal/low), prematurity (yes/no), delivery type (vaginal/C-section), and maternal effortful control scores. The full model containing all predictors was statistically significant, X2 (5, N=230) =24.610, p < .001. Effortful control had an Exp(B) of .420, CI (.264, .668) p<.001. Those women who are still breastfeeding at six weeks have significantly higher self-reported effortful control than those who are not still breastfeeding at six weeks, controlling for several other known correlates of breastfeeding continuation. Effortful control was found to predict decreased breastfeeding at six weeks. Because effortful control is an aspect of temperament, and is therefore relatively fixed, its measurement may be useful for identifying women who are less likely to breastfeed so they can be targeted by health educators and clinicians for more intensive intervention. Any increase in breastfeeding holds the potential for positive health outcomes for both mother and child.

This quasi-experimental study, using Orem's Nursing Systems Construct as a theoretical base, was conducted to determine the effects of education and support given by a lactation consultant on early breastfeeding problem incidence and resolution. Mothers were recruited in the hospital and interviewed by telephone two to three weeks postpartum to determine problem incidence, rate of resolution, perception of the problems' interference, self-care measures, and support network characteristics. The study sample consisted of 16 first-time breastfeeding mothers placed in naturally occurring experimental (n = 7) and control (n = 9) groups. The groups did not differ significantly in age, education, ethnicity, mode of birth, or presence of a support person in the home. The groups did not differ significantly in number of problems, problem resolution length, or perceptions regarding problems' severity. A significant difference was found in the use of formula supplements, with the control group using supplementation more than the experimental group.

The natural practice of breastfeeding has been strongly noted as one of the most cost-effective, health promoting, disease-prevention strategies of the 21st century. Although primary health organizations recommend exclusive breastfeeding for the first 6 months of life with added complementary foods and continued breastfeeding up to 2 years of age or longer, many mothers do not breastfeed their infants for the recommendation length of time. Applied policies and health practices, such as those described under the 10 Steps to Successful Breastfeeding and The International Code of Marketing of Breast Milk Substitutes, have been noted as contributing factors that can considerably impact the manner which women choose to feed their infants. A cross-sectional methodology assessed associations between maternity health practices and breastfeeding duration among women birthing in the United States. A secondary data analysis of the Infant Feeding Practice Study II and its Year 6 Follow-Up was conducted using IBM SPSS Statistics Version 24. Procedures for data analysis included frequencies, Ï?2 tests, and ordinal logistic regressions. Outcomes revealed that feeding infants any formula during their hospital stay drastically reduces the likelihood for prolonged breastfeeding duration. Study results also concluded that offering a pacifier to infants during their hospital stay reduced the length of breastfeeding duration. This study confirms many of the primary breastfeeding practices that are at the frontline of maternity patient care in the United States. Establishing well-grounded practices that aid in the long-term duration of breastfeeding could help save lives and improve child and maternal health outcomes within the United States.

Breastmilk feeding at birth demonstrates short- and long-term medical and neurodevelopmental advantages. Infants who are exclusively breastfed demonstrate less nausea, vomiting, and diarrhea, and they experience less upper respiratory and ear infections than do infants who are not breastfed. One strategy that supports breastfeeding initiation is providing skin-to-skin contact (STS) with mothers and newborns immediately upon birth. The purpose of this project was to evaluate the impact of a second session of STS on the postpartum unit on exclusive breastfeeding rates at discharge. A retrospective comparison design using Swanson's caring model was used to guide the evaluation study that examined and compared the rate of exclusive breastfeeding before and after the new model of care was implemented. The historical controls rate included all delivered women in a 3-month period who expressed a desire to exclusively breastfeed and who had one session of STS. In this group, the exclusive breastfeeding rates were 46% at discharge. After the practice change, the 75 women who expressed a desire to exclusively breastfeed and who had the second session of STS demonstrated exclusive breastfeeding rates of 72% at discharge. The increased rate of exclusive breastfeeding and the promotion of newborn health represent a major contribution to positive social change through the introduction of a second session of STS. The extension of the STS practice from only the immediate postdelivery setting to the postpartum setting provides a contribution to nursing practice that can be shared in any birth or similar practice setting.

The American Academy of Pediatrics and World Health Organization recommend exclusive breastfeeding for the first 4-6 months of life to reduce risk of obesity in pre-school children. Previous research has indicated a high rate of obesity among Hispanic children in the northeastern United States. There is also a gap in the literature regarding the effectiveness of exclusive breastfeeding in preventing obesity among preschool Hispanic children. Therefore, the purpose of this study was to determine if there was an association between exclusive breastfeeding and obesity among pre-school Hispanic children enrolled in the Special Supplemental Nutrition Education Program for Women, Infants and Children (WIC) in a metropolitan area of mid-Atlantic region between the years 2004 and 2009. This retrospective secondary analysis of data for 4454 Hispanic children compared the body mass index (BMI) at 36-59 months of age for those that were breastfed to those that were not breastfed using the Student's t-test. Duration of exclusive breastfeeding was examined for any correlation with BMI for the cohort of breastfeeding women using Pearson's correlation analysis. Results revealed that the BMI for 1181 breastfed children was not statistically different from the non-breastfed children (16.97 vs. 17.04). However, there was a statistically significant inverse relationship between duration of breastfeeding and BMI among children of breastfeeding mothers (r = -.75, p < .05). These results make an important contribution to the existing literature and can enhance social change initiatives by encouraging practitioners to educate Hispanic mothers on the positive effects of exclusive breastfeeding the first 4 months of life which could help minimize obesity prevalence among children.

Breastfeeding is the best infant feeding method, and breastmilk has many immunological and anti-inflammatory properties that protect babies against illnesses and diseases. It protects the health of the mother and saves society substantial economic costs, as demonstrated in many studies. Studies show that if 90% of U.S mothers breastfed for 6 months, up to $13 billion in healthcare costs could be saved. Despite the health and economic benefits of breastfeeding, most women stop breastfeeding before 6 months postpartum, which falls short of the recommendations of the World Health Organization, U.S. Surgeon General, and American Academy of Pediatrics. This study explored the effects of hand expression with lactation support on first-time mothers' self-efficacy for breastfeeding and breastfeeding duration among vaginal and Cesarean delivery mothers at a healthcare center in Oregon. The pretest posttest quasi-experimental design was used on 32 women with 4 repeated-measures ANOVA, and the women were followed up for 6 weeks postpartum. The women in the intervention group received the hand-expression intervention after the first breastfeeding until their white milk had been established. Results showed a large effect of the hand-expression intervention with lactation support on the dependent variable of self-efficacy, with an effect size of 0.888, and the dependent variable of breastfeeding duration, with an effect size of 0.801. Further, self-efficacy and breastfeeding duration increased over time. The results may inform policy development to increase women's self-efficacy and breastfeeding duration, which could help babies, mothers, and society to derive maximum benefits from breastfeeding.

The Breastfeeding Education Support Team (BEST) is a pilot project to promote breastfeeding in WIC clients in Tucson, Arizona. In this study, the control group breastfed their infants significantly longer than the intervention group (p < .006). Ethnicity and perceived support were shown to positively affect breastfeeding longevity in the control group. The intervention did increase the probability that a client receiving it would initiate breastfeeding (p < 0.06). The trimester a client attended the BEST class did significantly affect the longevity of breastfeeding in the intervention group (p < 0.016). The control group appeared to be influenced by cultural norms that favor breastfeeding. The intervention group seems to be functioning under transitional influences that do not favor breastfeeding. Strategies that include the BEST class, homevisiting a new breastfeeding mother, and the formation of breastfeeding support groups could increase the initiation and longevity of breastfeeding in this population.

Detrusor instability is the commonest type of urinary incontinence in the elderly and is present in up to 50% of patients attending continence clinics. Treatment of this condition, aimed at reducing uncontrollable detrusor contractions, is at present unsatisfactory. For example, calcium antagonists are cliniclly disappointing and studies were carried out to investigate why they are ineffective. Rats were treated with nimodipine for 8 days or with a single dose. Treatment for 8 days had no effect on isolated detrasor contraction but a single dose reduced detrasor contractile response. It is propossed that chronic treatment with nimodipine caused an up-regulation of calcium channels as a compensatory mechanism. Oestrogens have been shown to have an inhibitory effect on detrusor muscle contraction after in vitro and in vivo treatment. In post-menopausal women with a uterus unopposed oestrogens should not be given, but progesterone has anti-oestrogenic actions. When rats were treated with oestrogen and progesterone for 8 days, there was no effect on rat detrasor contractile response. An anti-oestrogenic effect of progesterone has therefore been demonstrated in rat detrusor smooth muscle. Caffeine has been shown to increase detrasor pressme on bladder filling in patients with detrusor instability. The effect of low concentrations of caffeine on the contractile response of isolated human and rat detrusor muscle was therefore determined. Caffeine was found to have only a slight potentiating effect on isolated human and rat detruosr muscle contraction. The results in this thesis have important clinical imphcations for the treatment of detrusor instability. It may be more effective to administer calcium antagonists in an intermittent manner. Oestrogens are better given alone or with the lowest possible dose of progestogens. Caffeine would not be contraindicated in patients with detrusor instability.

There has been a great deal of research investigating drug combinations which can increase analgesia. A number of studies have been conducted with one particular combination--opioids combined with the amphetamine drugs. Despite the existing literature, this combination is rarely used in clinical practice. One purpose of this thesis is to review the literature pertaining to the opioid-amphetamine combination. Another purpose of this thesis is to investigate whether dextroamphetamine sulfate ($ circler$Dexedrine) can potentiate morphine sulfate analgesia in rats in the formalin test (Experiment 1). To investigate whether these results can be generalized to another psychostimulant, methylphenidate hydrochloride ($ circler$Ritalin) is used in Experiment 2. Methylphenidate has been chosen instead of another amphetamine drug because it is currently being used in clinical studies without supporting evidence from animal studies. The results of the two experiments indicate that low doses of d-amphetamine and methylphenidate can potentiate the analgesic effects of morphine.

Mestrado em Biomedicina Molecular
Um dos principais mecanismos reguladores da função celular é a fosforilação de proteínas. É de focar que a fosforilação anormal de proteínas-chave pode estar associada a várias patologias, incluindo o cancro. Embora já existam muitos estudos sobre cinases no cancro, o conhecimento sobre as fosfatases que antagonizam a acção das cinases é muito menos. A PP1, uma das principais proteínas fosfatase de serina/treonina expressa em todas as células eucarióticas, está envolvida em vários processos celulares incluindo apoptosis e ciclo celular. Na realidade, diversos estudos demonstram que a PP1 regula variadas proteínas que são elementos-chave no processo de tumorigenesis. A AKT, uma cinase serina/treonina que se encontra desregulada em vários tipos de cancro, é um factor crucial na progressão e sobrevivência de melanoma. Prodigiosina, um membro da família de metabolitos secundários tripirrolicos pigmentados de vermelho, as prodigininas, demonstra propriedades anticancerigenas em vários tipos de cancro. Na verdade alguns estudos verificaram que a AKT é desfosforilada pela prodigiosina embora ainda seja desconhecido o mecanismo pelo qual tal acontece. Dada a importância da AKT na progressão e sobrevivência do melanoma e a capacidade da PP1 em desfosforilar a AKT é possível que a PP1 esteja envolvida em tal mecanismo. Os resultados preliminares demonstraram que a PP1 liga-se a um membro da família das prodigininas provando a interacção entre estas moléculas. Por outro lado, ensaios em linhas celulares de melanoma usando tratamentos com prodigiosina e cantaridina, um inibidor da PP1, demonstraram que a prodigiosina afecta isoformas da PP1 diferencialmente. Estes resultados sugerem que a prodigiosina actua em duas vias de sinalização distintas em melanoma, a via da AKT e a da MAPK, uma vez que alteração nos níveis de PP1α, uma das isoformas da PP1, se correlaciona com a variação dos níveis de fosforilação da AKT e as mudanças nos níveis da PP1γ com a variação dos níveis de fosforilação da MAPK. Com estes resultados propomos um modelo de como a prodigiosina desfosforila a AKT e como este processo contribui para a indução da morte celular em células de melanoma. Esperamos que este modelo ajude na compreensão do mecanismo de acção da prodigiosina bem como no reconhecimento das fosfatases como novos alvos terapêuticos no tratamento de cancro.
Protein phosphorylation is a major regulatory mechanism for cell function. It is noteworthy that several pathologies, including cancer to be associated with abnormal phosphorylation of key proteins. Although many studies have addressed the kinases that are misregulated in cancer, much less is known about the phosphatases that counteract their actions. PP1, a major serine/threonine protein phosphatase that is ubiquitously expressed in all eukaryotic cells, is involved in many cellular processes including apoptosis and cell cycle. In fact, several studies demonstrate that PP1 regulates several proteins that are key elements in the tumorogenesis process. AKT, a serine/threonine kinase that is disregulated in several types of cancer is a crucial factor in melanoma progression and survival. Prodigiosin, a family member of the natural red pigmented tripyrrolic secondary metabolites, prodiginines, show anticancer properties in numerous types of cancer. In fact, some prodigiosin studies demonstrate that AKT is dephosphorylated by prodigiosin by an unknown mechanism. Given the importance of AKT in melanoma progression and survival and the capacity of PP1 to dephosphorylate AKT it is possible that PP1 is involved in this mechanism. Our preliminary results showed that PP1 binds to one member of prodiginine family proving the interaction between these molecules. On the other hand, experiments with melanoma cell lines, using prodigiosin and cantharidin, a PP1 inhibitor, treatments, demonstrate that prodigiosin affect differently PP1 isoforms. These results suggest that prodigiosin acts in a different way in two altered pathways in melanoma, AKT and MAPK, since the alterations in PP1α levels, one of PP1 isoforms, are correlated with the conversion in AKT dephosphorylation and the variations in PP1γ levels with the changes in MAPK dephosphorylation. Given these results we propose a model of how prodigiosin dephosphorylates AKT and how this process contributes to induce cell death in melanoma cells. We expect that this model helps to understand prodigiosin action mechanism as well as acknowledge phosphatases as a therapy target in cancer treatment.

Cell-based metabolomics using LC-MS systemizes the study of the uniqueness of small-molecule metabolite (metabolomes) profiles in cellular processes. Cell-based metabolomics can potentially be used in many applications for the study of biological perturbation from stimulants in cellular pathways. The advantages of cell-based metabolomics include ease of control and interpretation when compared to the study of human subjects and animal models. Furthermore, this method can decrease some highly challenging problems that occur in genomics, transcriptomics and proteomics. Nowadays, cell culture in metabolomics studies has been used in many applications. These include cell culture and bioreactor optimisation, phenotype classification, stimulant testing effect, target and toxicity analysis, metabolic networks determination and modelling, and biomarker and drug target discovery. In this study, the reverse phase-liquid chromatography-mass spectrometry and hydrophilic interaction chromatography-mass spectrometry for comprehensive metabolic profiling well suited to the untargeted analysis of non-polar and polar metabolites in mammalian cells were developed, optimized and validated. These methods can separate and detect most of hydrophobic and polar metabolites that are normally found in mammalian cell lines. After that the LC-MS methods were applied to assess the effects of drugs with known and unknown cellular metabolic effects on three mammalian cell lines, namely HMVECs for antipsychotics experiment, MCF-7 cells for cordycepin experiment and MIN6 cells for fluoxetine experiment by using untargeted metabolic profiling. The global effects of antipsychotics at high therapeutic dosage in HMVECs were investigated. The results support for the toxicity hypothesis with measurements that confirm previous findings and reveal the exact biological pathways of antipsychotic-altered BBB functions. It was found that antipsychotics may affect the bioenergetics pathway due to mitochondrial dysfunction resulted in ketoacidosis and inducing oxide stress by reactive oxygen species generation. In the MCF- cell experiment, the results of the untargeted metabolite profiling demonstrated the clear anti-breast cancer effects of cordycepin and pentostatin. By investigating the metabolite profiles, clear synergistic effects of cordycepin and pentostatin combined in comparison to cordycepin activity alone in MCF-7 cells was observed. Furthermore, the pathway analysis indicated that anti-breast cancer activity was mainly responsible for alterations in purine and pyrimidine metabolism and bioenergetics. Additionally, cordycepin may be involved in the inhibition of cell proliferation and differentiation, and the activation of cell apoptosis. The last experiment on MIN6 cells, the developed and optimized HILIC-MS approach in order to determine the biological pathways which are impaired by fluoxetine on glucose-stimulated insulin secretion on MIN6 cell lines was performed. It is found that fluoxetine may impair glycolysis, TCA and fatty acid metabolism on MIN6 cell lines. Moreover, it is also reveal that the alteration of biological pathways on MIN6 cells by known ETC inhibitors (rotenone (Complex I inhibitor) antimycin (Complex III inhibitor)) and azide (a complex IV inhibitor). From comparison with these ETC inhibitors, it is found that fluoxetine may have the same effect pattern with azide.

Questa tesi affronta il problema di studiare il comportamento cognitivo negli animali attraverso metodi di analisi statistica e modelli dinamici stocastici. Negli esperimenti analizzati sono stati utilizzati degli esemplari di Drosophila Melanogaster confinati in un'arena a quali sono state somministrate droghe diverse in diversi esperimenti; parte integrante dello studio riguarderà l'influenza di queste droghe. Lo scopo è esaminare il comportamento cognitivo degli animali attraverso l'analisi statistica degli incontri tra esemplari che possono avvenire sia per una situazione casuale che per una decisione dell'animale stesso. Per evidenziare la presenza di questa interazione sociale è stato prodotto un modello nullo dell'esperimento: diversi parametri estratti dai dati in possesso permettono la generazione di percorsi casuali. Assumendo la sua capacità di rappresentazione, differenze significative dal modello nullo indicheranno la presenza di comportamenti cognitivi.

Introduction: Lipid abnormalities including increased total cholesterol, triglycerides, and lowdensity lipoprotein-cholesterol have been frequently reported in renal transplantation and could be involved in the high frequency of cardiovascular disease in this population. Immunosuppressive therapy appears to be a main factor that influences the post-transplant lipid profile. Cyclosporine A (CsA), rapamycin (RAPA), tacrolimus (TAC) and mycophenolate mofetil (MMF) are commonly used immunosuppressant in solid organ transplant patients. Several of these immunosuppressive agents including CsA, RAPA and TAC appear to have a significant effect on patient lipid level. Although RAPA does not seem to cause nephrotoxicity as commonly seen in patients treated with CsA or TAC, it seems to be associated with an incremental increase in triglyceride level. However, the immunosuppressive-induced hyperlipidemia has not been sufficiently described. Purpose: Our aim was to determine the effects of these drugs in vitro on key regulatory enzymes of lipid metabolism; Cholesteryl Ester Transfer Protein (CETP), hepatic lipase (HL) and lipoprotein lipase (LPL) activity within human plasma, as well as the in vivo effects of TAC on these enzymes in renal transplant patients. In addition, we also investigated the effects of RAPA and TAC on cholesterol efflux from human THP-l macrophages. Methods: The effects of CsA, TAC, RAPA and MMF on CETP, HL and LPL activity were first determined in vitro in human normolipidemic plasma and post-heparin normal human plasma, respectively. We further investigated the in vivo effects of TAC on these enzymes activities in renal transplant patients for one month following transplantation. The cholesterol efflux study was conducted independently to assess the effects of RAPA and TAC on ApoA-I- and HDL-mediated cholesterol efflux from human THP-l macrophages, as well as adenosine-triphosphate binding cassette (ABC)Al and ABCG1 protein expressions in these cells. Results: Our in vitro CETP study showed that CsA and RAPA induced CETP activity in human normolipidemic plasma in a dose-dependant manner. Although, none of these drugs, CsA, TAC, RAPA and MMF affected in vitro HL activity, these drugs suppressed the LPL activity in the post-heparin plasma. Unlike TAC, RAPA was shown to decrease apoAl-mediated cholesterol efflux and ABCA1 protein expression in human THP-l macrophages. In agreement with our in vitro result, our clinical study demonstrated that TAC significantly increased triglyceride levels and reduced the LPL activity in the renal transplant patients, regardless of the patients were on statin or not. Conclusions: These findings suggest that the increase in CETP activity, suppression in LPL activity and inhibition in the cholesterol efflux following either CsA, RAPA or TAC treatments observed in the present study may be associated with hypercholesterolemia and hypertriglyceridemia seen in patients administered these drugs.

This study examined the relationship between active support of the breastfeeding mother and breastfeeding rates in the WIC population. The study consisted of two groups, a control group and an intervention group. Participants in the experimental group received scheduled contacts from a lactation educator in the form of home visitations, telephone calls, and written communication, while the control group participants were encouraged to seek breastfeeding support as needed. Demographic measures, duration of breastfeeding, number of breastfeeding support contacts, and formula supplementation were recorded for all subjects. Women in the experimental group received significantly more breastfeeding support contacts than those in the control group; however, breastfeeding duration was similar among women in both groups. Women who requested six or more cans of powdered formula breastfed for a significantly shorter time than those who requested lesser amounts of formula. These results suggest postpartum breastfeeding support, in isolation, may be inadequate to encourage sustained breastfeeding.
Department of Family and Consumer Sciences

Thesis (M. Tech. (Biomedical technology)) - Central University of technology, Free State, 2013
Thirty-one years after the discovery and isolation of the human immunodeficiency virus (HIV) by French and American scientists, much progress has been made in basic research, clinical treatment, and public heath prevention. Although, much evidence of mother-to-child-transmission (MTCT) of HIV has been amassed since then, not much of it describes the effects of HIV on the nutrient composition of breast milk. The aim of this study was to determine the effects of HIV on the nutrient composition of breast milk, by studying two groups of adult lactating respondents from the same socio-economic background, who were chosen randomly and participated voluntarily. The study population consisted of 60 breastfeeding mothers, divided into two groups of 30 mothers each. Group one represented the control group of HIV non-infected mothers whereas group two consisted of HIV-infected mothers who did not receive any treatment. After a registered medical nurse took blood and breast milk samples, analysis was done on ethylenediamine tetra-acetic acid (EDTA) whole blood to determine the haematological and immunological parameters and breast milk was analyzed for nutrient composition. Standard laboratory operating procedures (SOP) were followed, throughout, to determine the parameters of the blood and breast milk samples. Results showed that associations between the socio-economic statuses (SES) of the two respondent groups could be established. Albeit differences were not significant, some were, however, detected in the number of people contributing to the household income of the respondents (p = 0.0051), their employment status (p < 0.0001) and the availability of water sources (p = 0.1124). It is believed that factors, such as the prevalence of HIV, if related to the different levels of SES may play an important role in the outcome of the health statuses of individuals at different levels of society. By implication, it is not the different levels of SES, but rather factors related to the different levels of SES that have an impact. Significant differences could be seen in the haematological variables between the two respondent groups: Red blood cell count (RBC) (p < 0.0001), hemoglobin (Hb) levels (p = 0.0119), hematocrit (Hct) (p = 0.0031), mean corpuscular volume (MCV) (p = 0.0005), mean corpuscular hemoglobin (MCH) (p = 0.0043) and monocyte count (p = 0.0275). These differences, however, were not significant to this study. Other differences that were significant were immunological parameters between the two respondent groups: CD4 cell count (p < 0.0001) and viral load, done only on the blood of the HIV-infected respondent group. The CD4 cell count is used as a guideline for the initiation of treatment for HIV-infected persons and is required to accurately assess the immune status of any patient at any given time. The viral load has long been established as a strong predictor of the rate of disease progression. The only significant difference in the breast milk composition was reflected in the following variables between the two groups: percentage (%) proteins (p < 0.0001) and calcium levels (p = 0.0081). The median and mean values of the percentage proteins were elevated in the subject group of mothers living with HIV, while calcium levels in the same group showed a decrease in both median and mean values. The lack of significant differences between the groups might be due to the small study population. If nothing else, this study highlights the need for further trials to evaluate the true effects of HIV on the nutrient composition of breast milk.

The purpose of this experimental study was to investigate whether a prenatal teaching intervention on position and attachment of the baby on the breast had any effect on postpartum nipple pain and trauma, and breastfeeding rates at six weeks. Many mothers who Initiate breastfeeding, discontinue because they experience nipple pain and trauma. Correct position and attachment of the baby on the breast for feeding Is paramount in preventing these problems. Using Orem's supportive-educative nursing system, i was hypothesised that the teaching Intervention would result in significantly less nipple pain and trauma, and would Increase breastfeeding rates at six weeks. The teaching in this intervention was given by a qualified midwife, who was also a lactation consultant, and who was not involved In any date collection. Seventy primiparae at a suburban hospital In Perth, Western Australia were randomly assigned to the experimental group (n = 36), who received the teaching Intervention as well as the usual prenatal education, or the control group (n=35) who received the usual prenatal education. During the first four postpartum days the LATCH Instrument was used to measure position and attachment of the baby on the breast; the Visual Analogue Scale (VAS) measured nipple pain, and tho Nipple Trauma Severity Index (NTSI) was developed to measure nipple trauma. A questionnaire measured demographic data, breastfeeding progress and breastfeeding rates at six weeks postpartum. The researcher was observer blind to group allocation unlit all observations were completed on day four postpartum. A significance level of 0.05 was set for all statistical procedures. There was no difference between groups for other variables which have the potential to influence breastfeeding success. All hypotheses were supported. Repeated measures ANOVA showed a significant difference between groups, with the experimental group having less nipple pain and trauma. Breastfeeding rates were analysed by Chi-Square (y²) and showed 92% of mothers in the experimental group and 29% In the control group still breastfeeding at six weeks postpartum. The findings of this study will have Implications for health professionals educating mothers on breastfeeding. It is anticipated that such an intervention has the potential to increase breastfeeding rates and encourage the continuation of breastfeeding up to at least six weeks postpartum.

Thesis (Ph. D.)--School of Pharmacy and Dept. of Chemistry. University of Missouri--Kansas City, 2004.
"A dissertation in pharmaceutical sciences and chemistry." Advisor: Thomas P. Johnston. Typescript. Vita. Description based on contents viewed Feb. 23, 2006; title from "catalog record" of the print edition. Includes bibliographical references (leaves 202-223). Online version of the print edition.

Thesis (Ph. D.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on December 20, 2007) Includes bibliographical references.

Impulsivity is a major component of mania in bipolar disorder, and patients also show impairments in decision-making involving risk on the Iowa Gambling Task (IGT). Similar deficits are also observed in some patients with temporal lobe epilepsy (TLE), in which seizures originate in the amygdala and hippocampal formations, and incidence of pathological gambling is higher in both these populations. Anticonvulsant drugs are widely used in the treatment of epilepsy, but also as mood stabilizers and prophylaxis for the management of bipolar disorder. Unfortunately, little is still known about the precise mechanisms of action underlying their efficacy, and the specific behavioural aspect targeted by these drugs. Patients with damage to the basolateral amygdala (BLA) also show deficits in decision-making, and rats with BLA lesions have shown such deficits in a variety of behavioural tasks. Few studies have looked at the effect of BLA stimulation on risky decision-making. This project first aimed at exploring the effect of the three anticonvulsant drugs currently also used as mood stabilisers- carbamazepine, valproate and lamotrigine- on aspects of decision-making using a rat analogue of the IGT, the rat Gambling Task (rGT). We then investigated the effect of kindling of the BLA on this task, with the aim of antagonizing any behavioural effects with the anticonvulsant drugs. Thirty-two rats in total learned the rGT. Sixteen rats were used in the pharmacology study, and 16 were implanted unilaterally with a bipolar electrode into the BLA and stimulated twice daily until kindling had been established i.e. three class five seizures were observed. Carbamazepine appeared to slow processing speed, decreased premature responses and also blocked the pro-impulsive effect of amphetamine. Kindling increased choice of the small, but immediate reward option P1 and also increased premature responses. However, none of the changes observed were permanent and therefore, we could not assess the effect of carbamazepine on blocking the effect of kindling. Further studies looking at chronic administration of anticonvulsants, and the effect of kindling on acquisition of the rGT, would help us understand the neurobiological mechanisms underlying vulnerability to impairments in decision-making under uncertainty associated with TLE and other psychiatric disorders.

The rich behavioural repertoire of the fetus provides a means of assessing central nervous system integrity, and thus the well-being of the fetus. Pregnancy in women with epilepsy is associated with a higher risk of congenital malformation and long-term developmental delay. The cause of these risks is thought to be the anti-epileptic drugs that women with epilepsy continue to take during pregnancy to prevent seizures. This thesis, using fetal behaviour as a diagnostic tool, studied the effect of the anti-epileptic drugs; Carbamazepine, Lamotrigine and Valproate on the fetal behaviour. The spontaneous behaviour and the habituation response of the fetus were examined at 12- 15, 18-22, 31 and 37 weeks of gestation in two groups of mothers; those mothers with epilepsy taking anti-epileptic drugs and a control group of mothers not having epilepsy and thus not taking anti-epileptic drugs. Further analyses examined the effects of the specific drug; mothers were taking Carbamazepine, Lamotrigine or Valproate with a group of mothers not taking anti-epileptic drugs. There was a significant difference between the fetuses in the Carbamazepine group and the control group higher at 12-15 weeks gestation. Total activity was significantly higher in the Carbamazepine group compared with fetuses not exposed to anti-epileptic drugs. Mean mouth movement scores were significantly lower at 18-22 weeks in fetuses exposed to Carbamazepine. Habituation performance was significantly different for the fetuses exposed to Carbamazepine at 31 weeks gestation. The . fetuses exposed to Carbamazepine showed a poorer habituation performance. Postnatally children who had been exposed Valproate scored significantly lower in both the mental and psychomotor developmental index scores of the Bayleys scale of Infant Development than children who had not been exposed to anti-epileptic drugs. Anti-epileptic drugs were observed to affect the behaviour of the fetus, suggestive of an effect on the central nervous system.

Until recently, all in vitro drug susceptibility assays of cytomegalovirus (CMV) were performed in clinically irrelevant fibroblast cells. This study sought to test if drug susceptibility was affected by cell type. MRC-5 embryonic lung fibroblasts and ARPE-19 retinal pigmented epithelial cells were infected with BADrUL131-Y4 epithelial/fibroblast tropic virus under serial concentrations of ganciclovir (GCV) or maribavir (MBV). Virus was quantified using plaque reduction, GFP fluorescence, and yield reduction. Both drugs performed less efficiently in ARPE-19 cells. A cell type effect was observed for both plaque reduction and yield reduction assays with implications for the treatment of CMV retinitis as well as other manifestations of CMV Disease that involve non-fibroblast cell types.

Despite extensive research into the effects of alcohol consumption, there is no clear understanding into the mechanisms underlying human information processing impairment. The acute consumption of alcohol was investigated to determine the implications for human information processing capabilities, and to identify the extent to which these implications were stage-specific. Further aims included the investigation and quantification of caffeine-induced antagonism of alcohol impairment. Moreover, the aforementioned relationships were investigated in morning versus evening conditions. A test battery of six resource-specific tasks was utilised to measure visual perceptual, cognitive and sensory-motor performance, fashioned to return both simple and complex measures of each task. The tasks implemented were: visual perceptual performance (accommodation, visual detection, visual pattern recognition); cognition (memory recall- digit span); and motor output (modified Fitts‟ and a driving simulated line-tracking). Performance measures were recorded by the respective computer based tasks. Physiological variables measured included heart rate frequency, heart rate variability (RMSSD, High and Low Frequency Power) and body temperature. Saccade speed, saccade amplitude, pupil size and fixation duration were the oculomotor parameters measured. Three groups of participants (alcohol, caffeine+alcohol and control) n=36 were studied, split evenly between sexes in a mixed repeated/non-repeated measures design. The control group performed all test batteries under no influence. The alcohol group performed test batteries one and two sober, and three and four under the influence of a 0.4 g/kg dose of alcohol. Group caffeine+alcohol conducted test battery one sober, two under the effect of caffeine only (4 mg/kg), and three and four under the influence of both caffeine and alcohol (0.4 g/kg). The third test battery demonstrated the effects of alcohol during the inclining phase of the blood alcohol curve, and the fourth represented the declining phase. Morning experimentation occurred between 10:00 - 12: 45 and 10:30 -13:15 with evening experimentation between 19:00 - 21:30 and 19:30 - 22:00. Acute alcohol consumption at a dose of approximately 0.4 g/kg body weight effected an average peak breath alcohol concentration of 0.062 % and 0.059 % for the alcohol and caffeine+alcohol groups respectively. Task-related visual perceptual performance demonstrated significant decrements for simple reaction time, choice reaction time and error rate. Cognitive performance demonstrated no significant performance decrements, while motor performance indicated significant decrements in target accuracy only. Physiological parameters in response to alcohol consumption showed significantly decreased heart rate variability (RMSSD) in the modified Fitts‟ task only. A significant decrease in saccade amplitude in the memory task was the only change in oculomotor parameters. Prior caffeine consumption demonstrated limited antagonism to task-related alcohol impairment, significantly improving performance only in reduced error rate while reading. Caffeine consumption showed stimulating effects on physiological parameters, significantly increasing heart rate and heart rate variability when compared to alcohol alone. The design of the tasks allows for comparison between complex and simple task performance, indicating resource utilisation and depletion. Complex tasks demonstrated higher resource utilisation, however with no statistical performance differences to simple tasks. Physiological parameters showed greater change in response to alcohol consumption, than did the performance measures. Alcohol consumption imposed significant changes in physiological and oculomotor parameters for cognitive tasks only, significantly increasing heart rate frequency and decreasing heart rate variability, skin temperature and saccade amplitude. Caffeine consumption showed no antagonism of alcohol-induced performance measures. Physiological measures showed that caffeine consumption imposed stimulating effects in only the neural reflex and memory tasks, significantly increasing heart rate frequency and heart rate variability. Prior caffeine consumption significantly decreased fixation duration in the memory task only. The time of day at which alcohol was consumed demonstrated significant performance and physiological implications. Results indicated that morning consumption of alcohol imposes greater decrements in performance and larger fluctuations in physiological parameters than the decrements in evening experimental sessions. It can be concluded that alcohol consumption at a dose of 0.4 g/kg affects all stages in the information processing chain. Task performance indicates that alcohol has a greater severity on the early stages of information processing. Conversely, under the influence of alcohol an increased task complexity induces greater effects on central stage information processing. In addition, caffeine consumption at a dose of 4 mg/kg prior to alcohol does not antagonise the alcohol-induced performance decrements.

The DNA damaging activity of RSU 1069 and seven of its analogues (RSU 1131, RSU 1164, RSU 1150, RB 7040, RSU 1172, RSU 1137 and RSU 1170) plus misonidazole and CB 1954 were investigated using the SOS-Chromotest The SOS-Chromotest is a genotoxicity assay that monitors the induction of the SOS response, which is induced in response to DNA damage. The strains used were PQ37, which possesses a uvrA mutation and is deficient in UvrA excinuclease activity, and PQ35, which is uvr and UvrABC excinuclease conpetent. These strains were exposed to the compounds being investigated under both oxic and hypoxic conditions. The results showed that RSU 1069 and some of its analogues were more active than misonidazole under both oxic and hypoxic conditions. This increase was due to their aziridine side-chains. With the exception of RSU 1137 and RSU 1170 all of the compounds showed altered SOS induction activities between oxic and hypoxic conditions. This alteration was shown to correlate with increased reduction of their nitro-groups under hypoxia. There was a difference in the hypoxic activities of RSU 1069 and some of its analogues between the uvrA-strain and the uvr -strain. With the uvrA-strain RSU 1069 showed decrease activity under hypoxia compared to oxia, whereas, the converse applied with the uvr -strain. This was interpreted to mean that RSU 1069 caused some damage that required an active UvrABC excinuclease to produce an SOS response. It has been proposed that this damage takes the form of DNA crosslinks. RSU 1137 showed insignificant SOS induction and this was demonstrated to be due to its nitro-group not being reduced. It was suggested that the ring opened aziridine side chain of RSU 1137 in some way inhibited its bioreduction. The order of activity of the drugs for SOS induction activities did not correlate with that for their toxicities. This indicated that DNA lesions other than, or in addition to, those responsible for cytotoxicity induced the SOS response. The DNA damaging activity and mutagenicity of RSU 1069 was also investigated using Ml3 phage rfDNA. Radiation reduced RSU 1069 was shown to produce some relatively long lived product that was more active towards DNA than unreduced RSU 1069, as judged by phage survival. Unreduced RSU 1069 was shown to be non-mutagenic, producing mutation rates under 1.5 times background level. The effect of strict hypoxic conditions upon the SOS response was investigated using the SOS-Chromotest with the uvrA tester strain. The results showed that the SOS response was induced under strictly anaerobic conditions in E. coli but that the response was altered compared to that obtained aerobically. The nature of the alteration was not determined as six different compounds, with five different modes of action, were used as SOS-inducers and all showed different types of response under hypoxic conditions.

Este trabalho pretende contribuir para o conhecimento geral da resposta imunológica do mosquito ao parasita da malária, uma vez que a elucidação das interacções entre vector e parasita poderão facilitar o desenvolvimento de medidas eficientes para bloquear a transmissão. As experiências realizadas neste trabalho incluíram o uso de Drosophila melanogaster como modelo de estudo das respostas imunológicas do mosquito e a avaliação do impacto da presença de esporozoítos de Plasmodium na hemolinfa do mosquito através da determinação de alterações no número de hemócitos, activação da reacção de melanização e do padrão de expressão de proteínas na hemolinfa do mosquito. O fármaco antimalárico cloroquina promove a transmissão no mosquito e tem sido relacionado com a expressão diferencial de péptidos antimicrobianos no mosquito. Para avaliar o efeito da cloroquina na sua produção usámos o modelo Drosophila, uma vez que a expressão e síntese de péptidos antimicrobianos na mosca está bem caracterizada, assim como as vias de sinalização da resposta imunológica. Os resultados deste trabalho não conseguiram provar algum efeito do fármaco na expressão e/ou síntese de péptidos antimicrobianos de Drosophila. O tratamento com cloroquina in vivo não afectou as vias de sinalização Toll e Imd, avaliado pela expressão de drosomicina e diptericina em moscas infectadas. Experiências in vitro em que se utilizaram linhas celulares derivadas de hemócitos de moscas produziram os mesmos resultados para a síntese de Drosomicina e Atacina. Experiências de sobrevivência de moscas infectadas e tratadas com cloroquina também não evidenciaram qualquer efeito do fármaco na resposta imunitária de Drosophila. Como este fármaco antimalárico tem um efeito conhecido na resposta imune do mosquito, propomos que a cloroquina tenha uma acção sobre moléculas específicas dos mosquito ou sobre diferentes vias de activação da sinalização que possam estar presentes apenas no mosquito. Por outro lado, a informação conhecida acerca do efeito da cloroquina na imunidade foi obtida após tratamento de humanos, ratinhos ou linhas celulares de mamíferos, implicando a metabolização do fármaco. Como tal, não é claro se o efeito observado resulta da acção do própria fármaco ou de um metabolito específico. Neste trabalho pretendeu-se também determinar as respostas do mosquito aos esporozoítos de Plasmodium na hemolinfa, uma vez que nesta fase da infecção no mosquito o parasita sofre uma grande redução no seu número. No hemocélio domosquito podem ser activadas respostas celulares e humorais. Durante o seu desenvolvimento no oocysto, os esporozoítos são cobertos por uma camada de proteína circumsporozoítica, que constitui o seu maior antigénio de superfície. Quando o oocisto rompe e os esporozoítos são libertados, esta proteína pode ser reconhecida pelas moléculas de reconhecimento presentes na hemolinfa levando à activação de respostas imunes. A activação de respostas imunitárias celulares contra os esporozoítos foi testada com base na determinação de variação do número de hemócitos quando estimulados com a proteína circumsporozoítica de P. falciparum. Apenas uma das doses (5ng) de proteína utilizadas para estimular linhas celulares de hemóctios causou uma redução significativa no números de hemócitos. Isto pode ser um reflexo de uma cinética de divisão celular mais lenta ou de destruição celular, apoptose, que poderia ser despoletada pela fagocitose de parasitas, por exemplo. Não foi possível obter uma resposta correlacionada com a dose usada para estimulação. No entanto, os hemócitos do mosquito parecem reconhcer a proteína do parasita e responder à sua presença. A activação da reacção de melanização durante a invasão da hemolinfa por esporozoítos foi testada, através da determinação da activação da enzima profenoloxidase e da actividade da fenoloxidase. Verificou-se que a actividade enzimática da fenoloxidase varia com o tempo em mosquitos submetidos a uma refeição sanguínea não infectante. A infecção por P. berhgei não pareceu impor variações na actividade da fenoloxidase. Diferenças subtis foram observadas aos dias 9, 12 e 15 pós-infecção, sendo a actividade enzimática mais elevada em mosquitos infectados. Os esporozoítos foram detectados na hemolinfa de mosquitos a partir do dia 9 pós-infecção, indicando que o parasita pode induzir um aumento subtil na activação da melanização. A actividade da fenoloxidase parece ser mantida constitutivamente num nível baixo, mesmo em mosquitos não infectados, o que pode explicar que apenas pequenas diferenças sejam observadas em mosquitos infectados. Injecções da proteína circumsporozoítica de P. falciparum em mosquitos não revelaram indução da actividade da enzima fenoloxidase. Apesar de não ter sido possível demonstrar conclusivamente a melanização de esporozoítos na hemolinfa, experiências de inibição da fenoloxidase mostraram que a actividade desta enzima é necessária para controlar o número de esporozoítos na hemolinfa e nas glândulas salivares. A hemolinfa é extremamente rica em proteínas, e conhecida por albergar a maior parte das moléculas do sistema imunológico necessárias ao reconhecimento, sinalização e à resposta efectora. Como tal, de modo a caracterizar o proteoma da hemolinfa durante a infecção por P. berhgei ao dia 13 pós-infecção, usámos umaabordagem que incluiu electroforese bidimensional e espectrometria de massa MALDITOF, visando identificar proteínas diferencialmente reguladas em mosquitos infectados. As proteínas com níveis alterados na hemolinfa de mosquitos infectados poderão estar envolvidas em processos fisiológicos como metabolismo de ácidos gordos, glicólise e transporte de iões. Estes resultados indicam que o parasita impõe alterações no metabolismo do mosquito, quer directamente quer levando o mosquito a alterar o seu próprio metabolismo como forma de conter a infecção. De facto, não há evidência se as alterações observadas são danosas ou necessárias para o desenvolvimento do parasita. No entanto, os nossos resultados sugerem que mecanismos fisiológicos do mosquito podem ter um papel na resposta imune. Um dado interessante obtido neste trabalho foi a inexistência de correlação entre a regulação a nível proteico e a nível do RNA na emolinfa. Isto pode derivar de uma janela de tempo diferente entre expressão génica e síntese proteica, uma vez que as amostras foram recolhidas ao mesmo tempo, ou pode reflectir um fonte diferente de RNA e proteína. O RNA amplificado para avaliar a expressão génica era originário dos hemócitos presentes na hemolinfa, enquanto que as proteínas podem ter sido produzidas quer pelos hemócitos quer pelo corpo gordo, que sintetiza a maior parte das moléculas imunes que são secretadas para a hemolinfa. No entanto, é importante tem em atenção que a informação resultante da análise de expressão génica ter de ser avaliada cuidadosamente, pois pode não ter uma regulação correspondente ao nível da proteína. A biosíntese de eicosanóides teve dois impactos distintos e opostos no desenvolvimento do parasita, promovendo e bloqueando a transmissão. Os eicosanóides parecem ser importantes para o desenvolvimento do parasita numa fase da infecção em que os esporozoítos se desenvolvem nos oocistos, enquanto que numa fasemais tardia, estas moléculas parecem ser importantes para controlar o número de parasitas na hemolinfa. Os nossos resultados sugerem que o parasita possa imunosuprimir o mosquito. A resposta do mosquito ao Plasmodium parece ser muito complexa, envolvendo acções de ambos os organismos. Para responderà invasão da hemolinfa pelos esporozoítos, o mosquito parece depender de diferentes mecanismos, como a fagocitose e a melanização. Para além destes, moléculas envolvidas em processos fisiológicos do mosquito são também afectadas pela infecção. Os nossos resultados sugerem que a resposta imunológica do mosquito possa envolver mecanismos para além daqueles que são tradicionalmente relacionados com a imunidade, como a biosíntese de eicosanóides. Verificámos também que pode não existir correlação entre a expressão génica e a síntese de proteínas, e como tal, a resposta imune deveria ser analisada em primeiro lugar por uma abordagem proteómica.
This work aimed at contributing to the general knowledge of the mosquito immune responses to the malaria parasite, in hope that the elucidation of vector/parasite interactions will facilitate the development of effective transmission blocking measures. Experiments performed here include the use of Drosophila melanogaster as a model for immunity studies in the mosquito and the evaluation of Plasmodium sporozoites presence in mosquito hemolymph impact on hemocyte numbers, melanization reaction responses and protein expression pattern. Chloroquine promotes malaria transmission in mosquito and it has been linked to differential AMP gene expression in mosquitoes. As Drosophila AMP expression and synthesis is well understood and as we have a good knowledge about immune signaling pathways, we chose this model to evaluate chloroquine effect on AMP production upon infection. Our results failed to show any drug effect on Drosophila AMP expression and/or synthesis. Drug treatment in vivo did not affect either the Toll or Imd immune signaling pathways, as shown when accessing drosomycin and diptericin expression in infected flies, and in vitro experiments using hemocyte-like cell lines produced the same results for Drosomycin and Attacin synthesis. Survival experiments were also performed in drug treated flies and failed to indicate any effect. For all the mechanisms tested, chloroquine did not seem to have any effect on Drosophila immunity. As this antimalarial drug has a known effect on mosquito immunity we propose that chloroquine may act on particular mosquito immune molecules or on different routes for pathway activation operating in the mosquito. Also, data obtained for chloroquine action on immunity were collected from treatment of humans, mice or mammalian cell-lines, implying that the drug is metabolized. Thus it is not clear if the observed effect results from an action of the drug itself, or from a specific metabolite. This would explain why direct drug feeding to flies would fail to produce an effect on Drosophila immunity. Another purpose of this work was to determine the mosquito responses to Plasmodium sporozoites in the hemolymph, as parasite development in the mosquito suffers a major bottleneck at this stage of infection. Both cellular and humoral responses may be triggered in the mosquito hemocel. Upon development inside the oocysts, sporozoites are covered with a layer of circumsporozoite protein, its majorsurface antigen. Recognition molecules present in the hemolymph may recognize sporozoites upon oocyst burst, possibly through its surface protein and activate immune responses towards it. Cellular responses towards sporozoites were tested, based on the evaluation of hemocyte number variation upon stimulation with the circumsporozoite protein of P. falciparum. Only one dose (5ng) stimulated hemocytelike cell lines and led to a significant reduction in cell numbers. This may reflect a slower cell-division kinetics or cell destruction, by apoptosis, following phagocytosis. We failed to show any dose-dependent response. Nevertheless, it seems that the CS protein is recognized by mosquito hemocytes that respond to its presence only in specific conditions. We also tested for activation of melanization reaction upon sporozoite invasion of the hemolymph by accessing PPO activation and PO activity. PO activity was found to vary over time in blood fed mosquitoes. P. berghei infection did not seem to impose variations in PO activity. Subtle differences were observed at D9, 12 and 15pi, when PO activity was higher in infected mosquitoes. Sporozoites were first detected in the hemolymph at D9pi indicating that parasite recognition may induce subtle increases in melanization activation. PO activity seems to be maintained at a low level even in noninfected mosquitoes. This may explain the fact that no great variations were observed upon infection. Pf-CS protein injections in mosquitoes failed to show PO activity induction. Although we could not conclusively determine sporozoite melanization, PO inhibition experiments showed that its activity is necessary for control of sporozoite load in the hemolymph and salivary glands. Hemolymph is an extremely protein rich environment, and known to harbor most of the immune molecules necessary for recognition, signaling and effector mechanisms. As such, we used a two dimensional electrophoresis approach coupled with MALDITOF mass spectrometry to compare the hemolymph proteome of P. berghei infected and non-infected An. gambiae mosquitoes at D13pi, aiming at the identification of differentially regulated protein in infected mosquitoes. Proteins found to have altered levels in the hemolymph of infected mosquitoes are predicted to be involved in physiological processes such as fatty acid metabolism, aminoacid synthesis, glycolysis and ion transport. This indicated that the parasite imposes alterations in the overall mosquito metabolism, either directly, or secondarly to combat infection. Actually we have no evidence if the alterations observed are harmful or necessary for parasite development. Yet, the results suggest that mechanisms operating in mosquito physiology may have a role on immune responses. An interesting fact is that protein regulation in the hemolymph did not correlate at any level with gene transcription. This may reflect a different time frame between transcription and protein synthesis, assamples were collected at the same time, or a different source for the RNAs and the tested proteins. RNA amplified to evaluate transcription was hemolymph, ie, hemocyte-derived, while hemolymph proteins may have been produced not only by hemocytes, but also by fat body cells, that synthesize the majority of immune-related molecules secreted into the hemolymph. Nevertheless, it is important to bear in mind that data resulting from gene expression analysis have to be carefully analyzed as it may not indicate direct protein synthesis. Eicosanoid biosynthesis was found to have two distinctive and opposite impacts in parasite development: both promoting and blocking transmission. Eicosanoids seem to be important for parasite biology and development, at a time when sporozoites are developing inside oocysts. At a later stage, these molecules seem to restrain sporozoite infection in the hemolymph. Evidence also point to mosquito immunosuppression by the parasite. Mosquito responses to Plasmodium seem to be highly complex, involving actions from both organisms. To respond to hemolymph invasion by sporozoites, the mosquito seems to rely on different mechanisms, such as phagocytosis and melanization. Additionally, molecules involved in physiological processes are affected by hemolymph infection. Data obtained by this work suggests that immune responses may include mechanisms other than those traditionally related to immunity, as in the case of eicosanoid biosynthesis. Also, our results indicate that correlation between transcription and protein synthesis is not sure to exist and thus, immune responses should be analyzed by proteomics in a first approach.

The adherence of three Candida species to human buccal epithelial cells (BECs) following treatment of the yeast with sub-inhibitory concentrations of amphotericin B, nystatin, miconazole nitrate, 5-fluorocytosine, octenidine and pirtenidine was investigated in vitro. Pre-incubation of C. albicans (two strains), C. tropicalis or C.kefyr with these antifungal drugs inhibited their adherence to varying degrees (reduction between 17% and 78% of the control value). Pre-treatment of yeast for a short period (l hr) had less effect on adhesion than pre-treatment for a long period (24 hr). Furthermore, treating C. albicans with a combination of amphotericin B plus 5-fluorocytosine, both at 1/8 MIC level, led to stronger adherence inhibition than that obtained for yeast pre-treated with either one alone at 1/4 MIC levels. In addition, the pre-treatment of either Candida or BECs or both types of cells with the drugs reduced adherence, the reduction being greatest when both types of cells were pre-treated. No difference in adherence between stationary or exponential phase yeast to BEC was observed and the drugs were effective in reducing the adherence of cells from either growth phase.

Thesis (M.A.) -- Central Connecticut State University, 2009.
Thesis advisor: Joanne DiPlacido. "... in partial fulfillment of the requirements for the degree of Master of Arts in Psychology." Includes bibliographical references (leaves 103-114). Also available via the World Wide Web.