• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 215
  • 207
  • 30
  • 23
  • 11
  • 11
  • 8
  • 8
  • 4
  • 4
  • 3
  • 3
  • 2
  • 2
  • 1
  • Tagged with
  • 739
  • 739
  • 206
  • 125
  • 99
  • 87
  • 80
  • 78
  • 69
  • 66
  • 53
  • 48
  • 43
  • 42
  • 42
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

The Impact of Psychosocial Variables on Immune System Functioning in a Sample of HIV-Positive Males

Richey, Gary K. 01 May 1992 (has links)
This study addressed the issue of the relationship between psychological well-being and immune function in a sample of HIV seropositive homosexual and bisexual males. A control group of HIV seronegative gay males was included. The study assessed the relationship between various psychological independent variables and immune system functioning over a 24-month time period for the seropositive subjects. Data on depression, coping style, psychosocial stress, and psychomatic symptoms were collected at baseline, as well as data on depression at 12 months and CD4 counts at 6-month intervals over a 2-year period. Preliminary analyses comparing HIV seropositive to HIV seronegative subjects showed differences on four of eight coping style scales, as well as on all of the psychogenic attitudes scales reflecting stress levels. There were no effects of eight coping styles on immune system functioning for the seropositives. However, there were significant relationships among four of six psychogenic attitudes scales (chronic tension, premorbid pessimism, future despair, and somatic anxiety) and immune system functioning for the seropositives. There were also significant effects of three scales measuring psychosomatic symptoms (Allergic Inclination, Gastrointestinal Susceptibility, and Cardiovascular Tendency) for the seropositives. However, there was no effect of level of depression on immune system functioning. The final chapter discusses the findings given the existing body of research. The emphasis is on the need to develop interventions targeting stress levels among persons with AIDS, as well as on conducting further research utilizing carefully constructed longitudinal research designs.
192

High Rates of Misdiagnosis of Pediatric Acute-Onset Neuropsychiatric Syndrome and How to Reduce Them

Centner, Aliya 01 January 2021 (has links)
Pediatric Acute-Onset Neuropsychiatric Syndrome (PANS) is a clinical diagnosis characterized by sudden onset of obsessive compulsive disorder and is considered a type of Autoimmune Encephalitis. Pediatric Autoimmune Neuropsychiatric Disorder associated with Streptococcal Infection (PANDAS) is a subset of PANS characterized by a similar presentation but specifically results from infection by Group A β-hemolytic streptococcus. Early and accurate diagnosis is essential, as PANS can become a chronic condition. PANS and PANDAS are frequently misdiagnosed. There are a variety of differential diagnoses. The intent of this thesis is to evaluate differences in symptoms between PANDAS patients and those with a differential diagnosis and to synthesize existing knowledge to evaluate research areas that need improvement and reduce the rate of misdiagnosis. A review of clinical studies on the PubMed database was done using the key terms: "pediatric autoimmune encephalitis," "pediatric acute-onset neuropsychiatric syndrome," "pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection," and "clinical study." A literature review was done to examine research articles and case reports to compare symptom presentation between PANDAS Patients and Differential Diagnosis Patients. The results of this thesis show that clinical studies only make up 2.73% of the articles and references on PubMed, revealing a need for increased clinical research. 16 symptoms were compared between PANDAS patients and Differential Diagnosis Patients. A One-Way ANOVA test was done, and 12 symptoms were found to be significantly higher in the PANDAS Patients compared to the Differential Diagnosis Patients. Symptom overlap between PANDAS Patients and Differential Diagnosis Patients and the results of the One-Way ANOVA test were compiled into a PANS Diagnostic Form for clinician use.
193

A Case Report of Catastrophic Antiphospholipid Syndrome with Libman-Sacks Presenting as Interstitial Pneumonia

Martin, Chassidy Sumler, Cannistraro, Rocco J 25 April 2023 (has links)
A Case Report of Catastrophic Antiphospholipid Syndrome with Libman-Sacks Presenting as Interstitial Pneumonia Chassidy Sumler Martin, MS, Rocco Cannistraro, MD Antiphospholipid syndrome (APS) is an autoimmune condition characterized by vascular thromboses and a positive antiphospholipid antibody. Catastrophic antiphospholipid syndrome (CAPS) is a rare disease that often results in death. CAPS is the most severe form of APS, which can develop in a short period of time and occurs in less than 1% of people with APS. CAPS involves multiple organs simultaneously with diffuse microvascular and macrovascular involvement. Here, we present a case of catastrophic antiphospholipid syndrome presenting as interstitial pneumonia that rapidly progressed to acute renal failure, acute ischemic cerebral infarcts, cardiac valvular vegetations, and heart failure. This case report aims to bring awareness of prompt medical suspicion and treatment of CAPS in hopes of improving disease outcomes.
194

Vliv chladového stresu na imunitní systém za působení infekčních agens / The effect of cold stress on the immune system in the presence of infection

Kratochvílová, Anna January 2021 (has links)
Although the relationship between the effects of cold and infection has been studied for a long time, the mechanisms contributing to this phenomenon have not yet been discovered. While short-term exposure to cold triggers a stress response and the production of proinflammatory cytokines, long-term cold exposure induces adaptation and anti- inflammatory shift. The role of cold adaptation in the development and the process of the organism's response to infection remains an unresolved issue. In this diploma thesis, we focused on determining the effect of cold stress or cold adaptation on the immune system of rats which was stimulated by ligands of Toll-like receptors (TLRs). The obtained results showed the importance of γδT lymphocytes and their cytokine production in the process of cold adaptation. To determine how cold adaptation affects the response to infectious agents, we studied changes in the proportion of different immune cell populations in rats treated with the TLR2/6 ligand Pam2CSK4. We determined significant changes in the activation of myeloid cells and B lymphocytes, but also in the population of γδT lymphocytes. Our obtained results suggested the importance of γδT lymphocytes and the protective effect of cold adaptation. Key words: immune system, cold stress, cold adaptation, infection,...
195

Effect of Sepsis on Circulating CTRP3 Levels

Musick, Adam, Shipley, Madison, Tu, Fei, Li, Chuanfu, Yakubenko, Valentin, Peterson, Jonathan 12 April 2019 (has links)
Effect of Sepsis on Circulating CTRP3 Levels Adam Musick, Madison Shipley, Fei Tu, Chuanfu Li, Valentin Yakubenko, and Jonathan M. Peterson. Adipose tissue is an active endocrine organ which secrets several pro- and anti- inflammatory mediators, collectively called adipokines. Our previous work has identified a novel anti-inflammatory adipokine called C1q TNF Related Protein 3 (CTRP3). Others have previously demonstrated that localized overexpression of CTRP3 protects myocardial tissue from lipopolysaccharide (LPS)-induced sepsis, further supporting the potential protective role of CTRP3. However, endogenous regulation of CTRP3 in response to a sepsis event has not been explored. Further, other adipokines have been identified as diagnostic/prognostic biomarkers for critically ill patients. Therefore, the purpose of this project was to determine the effects of a sepsis event on the circulating CTRP3 levels. METHODS: Gonadal adipose tissue and serum were collected 8 hours after induction of the cecal-puncture and ligation (CLP) model of sepsis or sham control mice. The circulating levels of CTRP3 were quantified by immunoblot analysis. The transcription levels of CTRP3 in adipose tissue were measured by Real-Time PCR. In addition, to explore a potential mechanism for a protective role of CTRP3, thioglycollate-induced peritoneal macrophages were isolated and binding of recombinant CTRP3 was determined by imaging flow cytometry. RESULTS: Circulating CTRP3 levels decreased by approximately 90% compared to sham mice. However, adipose tissue transcription levels of CTRP3 was not difference between CLP and sham mice. Further, imaging flow cytometry demonstrated that CTRP3 binds directly to isolated macrophages. CONCLUSION: The overserved reduction in circulating CTRP3 protein levels and the absence of changes to the CTRP3 transcription, indicate that during sepsis CTRP3 is actively removed from the blood. As CTRP3 binds directly to macrophages and has been previously shown to attenuate LPS-induced macrophage activation these data could indicate that under normal conditions CTRP3 combines with active macrophages to help suppress cytokine overexpression. However, it appears that during sepsis the endogenous CTRP3 levels are quickly depleted. Combine these data support future research to determine if circulating CTRP3 levels are a biomarker indicative of sepsis prognosis and to determine if increasing the circulating levels of CTRP3 could reduce the cytokine storm associated to a sepsis event. Further, as we have demonstrated CTRP3 binds directly to macrophages, future studies are also needed to explore the potential anti-inflammatory mechanism of CTRP3 action on macrophages.
196

ALTERATION OF CYTOCHROME P450 GENE EXPRESSION AND MICROBIAL PROFILES IN PATIENTS WITH ENDOMETRIOSIS

Do, Han 01 December 2023 (has links) (PDF)
Endometriosis is characterized by aberrant estrogen signaling and chronic inflammation that results in prolonged pelvic pain and infertility. Research from our lab along with others have found that the chronic inflammatory state is maintained by a high ratio of inflammatory/ tolerant (Th17/ Tregs) cells systemically as well as increased Treg localization (tolerance) within endometriotic lesions, allowing endometriotic lesions to escape effector immune clearance. Moreover, this phenotype creates an intolerant environment for successful implantation which poses a risk of infertility and pre-term delivery in this group of women. Our previous research has also found that women with endometriosis have microbial dysbiosis within both gastrointestinal and urogenital (GI/UG) environments that may contribute to abnormal metabolism of parent estrogens. We hypothesized that microbial disruption alters enterohepatic recirculation of endogenous hormones by changing expression of cytochrome P450 (CYPs) enzymes that metabolize parent estrogens. Along with presence of disease, many external factors might also contribute to microbial disruption within the urogenital environment such as sexual partner encounters. Surgical intervention and use of hormonal therapies for treatment of endometriosis, may also contribute to microbial composition within the GI and UG environments in diseased patients. Our goal for this study was to 1) measure several CYP enzyme gene expressions in both eutopic endometrium and ectopic endometriotic lesions of diseased subjects; and 2) investigate the association of sexual partner number on microbial profiles in vaginal, urine and fecal samples of diseased patients, and whether hormonal therapy and surgical intervention affect microbial dynamics within the GI and UG environments. Our data showed that CYP1B1 gene expression was altered in eutopic endometrium of diseased patients. Hormonal therapy (HT) increased CYP1B1 gene expression in both eutopic and ectopic endometrial tissue. Patients who had more than 7 sexual partners had increased microbial dysbiosis indicated by increased composition of anaerobic bacteria in fecal and vaginal samples, indicating that increased number of sexual partners further altered microbial dysbiosis in patients with endometriosis. In conclusion, our long-term goal is to identify a unique microbiome that may serve as a potential marker to detect the early onset of endometriosis. Our study contributes to current knowledge on the expression of CYP enzyme metabolites on endometriosis. Since our patient cohorts are divided based on hormonal and surgical treatment, we hope to contribute additional knowledge on the impact of pharmacological and surgical therapy on the expression of CYP enzymes in endometriosis. Moreover, we hope to gain more understanding about mechanisms that cause alteration of CYPs gene expression in patients with endometriosis. Understanding the pathophysiology of endometriosis is critical for advancement of novel therapeutic targets and treatment of disease. Through investigation of a patient’s immune system, endocrine regulation and microbial profiling, we hope to advance our understanding of the disease and identify potential areas for improving diagnostics and therapeutic interventions.
197

Microbiota induced immune system maturation plays a key role in development of normal behaviour

Philip, Vivek 11 1900 (has links)
Gut microbiota has been shown to regulate the growth and development of the central and enteric nervous systems (CNS and ENS) after birth. There is ample evidence to suggest that intestinal bacteria can influence behavior of the host through both immune and immune-independent mechanisms. Gut-microbiota-regulated CNS structural changes are focused in the limbic system, at centres associated with memory, social and emotional behaviour. Several studies using germ-free (GF) and specific pathogen free (SPF) mice demonstrated microbial influence on behaviour development accompanied by neurochemical changes in the brain. Higher exploratory and lower anxiety-like behavior was found in GF mice compared to SPF mice with lower central expression of neurotrophins, such as nerve growth factor and BDNF. The mechanisms by which the microbiota influences behavior are unknown but could be immune-mediated, neural, or humoral in origin. In this study I investigated the role of immune system maturation on mouse behaviour after bacterial colonization. I showed that mono-colonization of GF mice with E. coli normalizes behaviour similar to colonization with complex microbiota (SPF and ASF) and the continuous presence of bacteria is not required to maintain this normal behaviour. I also showed that innate immunity through the MyD88/Ticam pathway is crucial for the development of normal behaviour and that multiple innate immunity and neuronal genes are involved in this process. Together these results suggest that bacterial colonization primes and matures the innate immunity and development of the central nervous system ultimately leading to normal behaviour. I believe that bacterial colonization at birth is not only important for the epithelial barrier function, gut homeostasis, and immune functions, but also for the development of normal behaviour. Altered immune priming during the postnatal period due to abnormal microbial colonization may have wider implications when considering psychiatric disorders in humans. / Thesis / Doctor of Philosophy (PhD)
198

Effects of Short-Term Exposure to Octylphenol and Genistein on the Immune System of C57BL/6 and (NZBxNZW)F1 Mice

Becker, Kelcey Manae 16 September 1999 (has links)
Octylphenol and genistein are two of the growing list of endocrine disrupting chemicals found in the environment that mimic estrogen in reproductive tissue both in vitro and in vivo. It is well established that endogenous estrogens modulate not only the reproductive system, but also the immune system. However, the effects of many endocrine disrupting chemicals, such as octylphenol and genistein, on the immune system have yet to be determined. Preliminary studies on short-term treatment with genistein (0.6 mg) and octylphenol (10 mg) showed that the thymus of orchiectomized (NZBxNZW)F1 males is sensitive to these agents. Further studies focused on the effects of short-term treatment of octylphenol on the morphology and function of the thymus in adult, reproductively intact non-autoimmune C57BL/6 and pre-autoimmune (NZBxNZW)F1 males. Oral dosing of 0.1 mg, 1 mg, or 10 mg of octylphenol 3 times a week for 3 weeks did not affect the morphology or function of the thymus as assessed by its weight, thymocyte cellularity, proportion of immature and mature thymocytes, level of apoptosis, apoptotic rates of stimulated thymocytes, and proportion of mature T cells in the spleen. Furthermore, oral dosing of 0.1 mg, 1 mg, or 10 mg of octylphenol did not result in estrogenic changes in the reproductive tract in our model. Subcutaneous injection of 10 mg of octylphenol resulted in skin lesions that confounded the assessment of its affects on the thymus. Further studies are needed to definitively determine the effects of octylphenol on the immune system of both males and females of various ages and to determine the effect of long-term exposure. / Master of Science
199

Age-associated alterations in the immune system of normal and autoimmune-susceptible mice

Seth, Aruna 28 July 2008 (has links)
In this study, the effect of aging on various cells of the immune system was investigated. The two experimental models used were normal young (1-2 months) and old (22-24 months) DBA/2 mice and autoimmune-susceptible young (1-2 months) and old (5-6 months) MRL-Ipr/Ipr (Ipr) mice. Autoreactive T cell clones isolated from DBA/2 mice were used to study the age-induced differential responses of syngeneic T cells and B cells. These cell interactions were found to be greatly diminished in old DBA/2 mice, and this appeared to be due to an intrinsic defect in the cells from old mice. A decreased syngeneic mixed lymphocyte reaction (SMLR) was also found to be associated with these defects in T-T and T-B interactions. The decreased SMLR was due to a reduction in the production of interleukin-1 by macrophages from old mice. In the Ipr mice, age-induced alterations in the cell surface characteristics of the abnormal T cells that accumulate in the lymph nodes were studied. The double-negative T cells from the lymph nodes of old Ipr mice were found to express a cell surface marker, J11d, that is normally present only on immature T cells in the thymus. Furthermore, the number of double-negative J11d⁺ T cells also increased in the thymus of old Ipr mice. Autoreactive T cell clones isolated from DBA/2 and /pr mice exhibited the properties of both T<sub>H</sub>1 and T<sub>H</sub>2 subsets as the clones secreted IL-2, IL-4 and IFN-γ, and activated both B cells and macrophages. The current study indicates that with increasing age, the autoreactive T cell-induced immunoregulation is disturbed, which may account for reduced immune responsiveness to foreign antigens and increased susceptibility to autoimmune diseases. / Ph. D.
200

Pro-Tumorigenic role of ETS-related gene (ERG) in precursor prostate cancer lesions

Lorenzoni, Marco 14 October 2019 (has links)
Prostate cancer (PCa) is the second most common cancer in men with more than 1 million new cases worldwide each year. While some of the genomic, genetic and molecular events characterizing PCa have been functionally associated with tumor onset, development and resistance to therapy, the meaning of many other molecular alterations remains poorly understood. Recent development of organoids technology and prostate organoid cultures has established an innovative and valuable model for the study of adult tissue homeostasis, physiology and disease. In this project we combined prostate organoids technology with genetic engineering and CLICK-chemistry coupled Mass Spectrometry approaches in order to better characterize molecular features of wild type and genetically engineered mouse prostate organoids modeling early steps of human prostate tumorigenesis. In details, by manipulating mPrOs to proxy ETS-related gene (ERG) precursor PIN/HGPIN lesions of human prostate, we identified possible novel pro-tumorigenic roles of ERG which unleashes cells proliferation from the tight control of growth stimuli, and, even more interesting, corrupts immune system components to escape immune surveillance. In conclusion, this project shows that coupling innovative biological systems and technological approaches can lead to significant improvements in the analysis and understanding of disease mechanisms.

Page generated in 0.0352 seconds