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71.
72.
Lakshmi Krishnan Branka Pejcic-Karapetrovic Komal Gurnani Ahmed Zafer Subash Sad 《American journal of reproductive immunology (New York, N.Y. : 1989)》2010,63(1):54-65
Listeria monocytogenes (LM) preferentially colonizes the placenta and causes fetal loss and systemic disease during pregnancy. As systemic CD8+ T-cell memory is critical in controlling LM infection, we addressed the issue as to whether it is modulated during pregnancy.
Pregnant mice were infected with LM and their immune response was quantified relative to the non-pregnant cohort using advanced immunological techniques.
Pregnant mice exhibited progressive and massive placental LM infection leading to fetal resorptions. In contrast, they harbored significantly lower bacteria in spleen and liver relative to non-pregnant controls, and rapidly cleared systemic infection. Both pregnant and non-pregnant mice exhibited similar activation of systemic innate immunity. Moreover, LM infection in pregnant and non-pregnant hosts evoked strong antigen-specific cytolytic CD8+ T cells that produced IFN-γ. Consequently, LM infection initiated during pregnancy afforded long-term protective memory to secondary infection.
Maternal hosts generate a normal Listeria -specific adaptive immunity in particular CD8+ T-cell memory response suggesting that systemic listeriosis during pregnancy may be an immunopathology associated with placental infection. 相似文献
Method of study
Pregnant mice were infected with LM and their immune response was quantified relative to the non-pregnant cohort using advanced immunological techniques.
Results
Pregnant mice exhibited progressive and massive placental LM infection leading to fetal resorptions. In contrast, they harbored significantly lower bacteria in spleen and liver relative to non-pregnant controls, and rapidly cleared systemic infection. Both pregnant and non-pregnant mice exhibited similar activation of systemic innate immunity. Moreover, LM infection in pregnant and non-pregnant hosts evoked strong antigen-specific cytolytic CD8
Conclusion
Maternal hosts generate a normal Listeria -specific adaptive immunity in particular CD8
73.
Diagnostic usefulness of monoclonal antibody P504S in the workup of atypical prostatic glandular proliferations 总被引:7,自引:0,他引:7
We stained 37 prostate needle biopsies and 3 transurethral resections (TURP) containing atypical foci and 20 morphologically unequivocal prostate cancer biopsies, including 4 with foamy features, with P504S. Of 20 biopsies with unequivocal cancer, 18 showed variable P504S staining (sensitivity, 90%); 1 minute cancer and 1 foamy cancer lacked P504S staining. Of 40 cases with atypical foci (biopsies, 37; TURP, 3), 9 were diagnosed as high-grade prostatic intraepithelial neoplasia (HGPIN), 2 were excluded, and 29 had foci of atypical small glandular proliferation. Of these 29 cases, 7 were highly suggestive of cancer, 2 of which lacked P504S staining. In 22 cases with benign atypical foci, 11 were diagnosed as postatrophic hyperplasia (none expressed P504S) and 7 as atypical adenomatous hyperplasia (AAH; 1 showed focal weak P504S staining). Of 9 HGPIN specimens, 8 showed predominantly diffuse, moderate P504S staining. P504S has slightly lower sensitivity for detection of prostate cancer than found previously. Heterogeneous expression patterns may explain negativity in some biopsy specimens with minute cancer. In atypical small glandular proliferations, diffuse positive P504S staining in atypical glands strongly supports a cancer diagnosis, but negative staining does not exclude it. P504S seems to have low sensitivity for detecting foamy prostate cancer. Most HGPINs show diffuse moderate P504S staining. AAH may show focal P504S staining. We recommend using P504S along with morphologic examination and conventional basal cell markers. 相似文献
74.
Lakshmi Jayashankar Kathleen M. Brasky John A. Ward Roberta Attanasio 《Clinical and Vaccine Immunology : CVI》2003,10(5):870-875
The age-related modulation of lymphocyte number and function was assessed in a nonhuman primate model consisting of healthy olive baboons (Papio cynocephalus anubis) of ages encompassing the entire life span of this species. The objectives of this study were to characterize an animal model of immunosenescence and to assess whether or not age should be considered when designing studies for the evaluation of vaccine candidates in baboons. Specifically the following parameters were assessed in baboons from 6 months to 26 years of age: relative numbers of B lymphocytes, CD4+ and CD8+ T lymphocytes, and T lymphocytes expressing CD28, CD25, and phytohemagglutinin-stimulated lymphoproliferative activity; and concentrations of total immunoglobulin, soluble interleukin-2 receptor α, and soluble CD30 in serum. There was a statistically significant effect of age on lymphocyte numbers. As age increased, relative B-cell numbers (ranging from 6 to 50%) decreased (P < 0.001) and relative T-cell numbers (ranging from 28 to 80%) increased (P < 0.001). The increase in T-cell numbers involved both the CD4+ and CD8+ subsets. In addition, there was a significant negative correlation of age with levels of soluble interleukin-2 receptor α in serum. Modulation of lymphocyte numbers appears to occur gradually during the entire baboon life span, thus suggesting the presence of an age-related developmentally regulated process. These findings indicate that baboons represent a potentially useful model to study selected phenomena related to immunosenescence. These findings also indicate that, when using the baboon model for vaccine or other experimental protocols requiring the assessment of immune responses, it would be appropriate to take into account the age of the animals in the study design. 相似文献
75.
Although peripheral immune cells infiltrate ischemic infarct tissue and elicit immune injury, the role of Cytotoxic T Lymphocytes (CTLs) and the toxins they release in mediating neuronal death is not well understood. Granzyme-b (Gra-b), a serine protease found in the cytoplasmic granules of CTLs and natural killer cells, plays an important role in inducing target cell death by activating several caspases and by initiating caspase-independent pathways that contribute to target cell death. To determine if CTLs and Gra-b are involved in post-ischemic cerebral cell death; we investigated the role of CD8+ CTLs and Gra-b in ischemic rat brain infarct after transient middle cerebral artery occlusion (tMCAO) and in sham-operated animals. We observed that CTLs infiltrate the ischemic infarct within 1 h of reperfusion. There was a significant increase in Gra-b levels in the ischemic region starting from 1 h until 3 day which correlated with increased levels of chemokines (IP-10/CXCL10, IL-2) and TNF-α. Co-immunoprecipitation experiments show that Gra-b interacts with Bid, PARP, and caspase-3 in ischemic samples. Immunofluorescence analysis of Gra-b and TUNEL showed that Gra-b is present both in apoptotic and necrotic cells. Triple immunostaining further confirmed that the Gra-b positive degenerating cells were neurons. CTLs in close spatial proximity to degenerating neurons, increased levels of Gra-b, localization in neurons positive for TUNEL, and interaction with other pro-apoptotic proteins indicate that Gra-b and CTLs play a significant role in neuronal death following cerebral ischemia in the rat brain after tMCAO. Based on the above findings we support our hypothesis that Gra-b secreted from activated CTLs might be involved in aggravating post-ischemic damage by mediating neuronal death. 相似文献
76.
Jun Ren Lakshmi Pulakat Adam Whaley-Connell James R. Sowers 《Journal of molecular medicine (Berlin, Germany)》2010,88(10):993-1001
The metabolic syndrome is a constellation of metabolic disorders including obesity, hypertension, and insulin resistance,
components which are risk factors for the development of diabetes, hypertension, cardiovascular, and renal disease. Pathophysiological
abnormalities that contribute to the development of the metabolic syndrome include impaired mitochondrial oxidative phosphorylation
and mitochondrial biogenesis, dampened insulin metabolic signaling, endothelial dysfunction, and associated myocardial functional
abnormalities. Recent evidence suggests that impaired myocardial mitochondrial biogenesis, fatty acid metabolism, and antioxidant
defense mechanisms lead to diminished cardiac substrate flexibility, decreased cardiac energetic efficiency, and diastolic
dysfunction. In addition, enhanced activation of the renin–angiotensin–aldosterone system and associated increases in oxidative
stress can lead to mitochondrial apoptosis and degradation, altered bioenergetics, and accumulation of lipids in the heart.
In addition to impairments in metabolic signaling and oxidative stress, genetic and environmental factors, aging, and hyperglycemia
all contribute to reduced mitochondrial biogenesis and mitochondrial dysfunction. These mitochondrial abnormalities can predispose
a metabolic cardiomyopathy characterized by diastolic dysfunction. Mitochondrial dysfunction and resulting lipid accumulation
in skeletal muscle, liver, and pancreas also impede insulin metabolic signaling and glucose metabolism, ultimately leading
to a further increase in mitochondrial dysfunction. Interventions to improve mitochondrial function have been shown to correct
insulin metabolic signaling and other metabolic and cardiovascular abnormalities. This review explores mechanisms of mitochondrial
dysfunction with a focus on impaired oxidative phosphorylation and mitochondrial biogenesis in the pathophysiology of metabolic
heart disease. 相似文献
77.
Nair LS Lee DA Bender JD Barrett EW Greish YE Brown PW Allcock HR Laurencin CT 《Journal of biomedical materials research. Part A》2006,76(1):206-213
This study deals with the synthesis and in vitro osteocompatibility evaluation of two novel alanine-containing biodegradable ester polyphosphazenes as candidates to form self-setting composites with hydroxyapatite (HAp) precursors. The two novel biodegradable polyphosphazenes synthesized were poly[(ethyl alanato)1.0(ethyl oxybenzoate)1.0 phosphazene] (PN-EA/EOB) and poly[(ethyl alanato)1.0(propyl oxybenzoate)1.0 phosphazene] (PN-EA/POB). The polymers were characterized by multinuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC). Biodegradability and percentage water absorption of the polymers were evaluated by following the mass change in phosphate buffer (pH 7.4) at 37 degrees C. PN-EA/POB underwent faster degradation and showed higher water absorption compared to PN-EA/EOB. Both polymers became insoluble in common organic solvents following hydrolysis presumably due to crosslinking reactions accompanying the degradation process. Osteoblast cell adhesion and proliferation on PN-EA/EOB and PN-EA/POB was followed by scanning electron microscopy (SEM) and by using a biochemical assay. Both PN-EA/EOB and PN-EA/POB supported the adhesion and proliferation of primary rat osteoblast cells in vitro. Furthermore, the enzymatic activity of the osteoblast cells cultured on the polymers was confirmed by the alkaline phosphatase activity. Thus, these biodegradable amino-acid-based polyphosphazenes are promising new materials for forming self-setting bone cements. 相似文献
78.
Central nervous system (CNS) shunt infection is a cause of significant morbidity, causing shunt malfunction and chronic ill health. This study was carried out to evaluate the infection rate associated with CNS shunts, assess the frequency of the pathogens as well as their antibiotic sensitivity pattern aiming at suitable prophylaxis. A retrospective analysis of 226 CSF cerebrospinal fluid (CSF) shunt procedures sent for bacteriological work up over a period of one year and six months was undertaken. Laboratory diagnosis was established by subjecting the CSF to cell count, biochemical tests, bacteriological culture and antibiotic susceptibility test. Nine out of 226(3.98%) of the CSF samples were culture positive. Coagulase negative Staphylococcus was the most common isolate accounting for 36.36%. Majority of the isolates were sensitive to the thirdgeneration cephalosporins and quinolones. The antibiotic sensitivity pattern suggests cephalosporins and quinolones to be a better choice of antibiotics either prophylactically or therapeutically, which may result in effective and rapid sterilisation of the CSF. 相似文献
79.
Neeraja M Lakshmi V Teja VD Umabala P Subbalakshmi MV 《Indian journal of medical microbiology》2006,24(4):280-282
Dengue is an acute infectious disease of viral etiology. It is probably one of the most important arthropod borne viral disease in terms of human morbidity and mortality. The spectrum of disease ranges from self-limited dengue fever to more severe forms of dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS). Laboratory diagnosis of dengue virus infection mainly depends on detection of virus specific antibodies. The aim of the study was to correlate the serological results with clinical presentation in patients with a diagnosis of dengue. Eleven out of 15 (73.3%) patients with DHF and DSS had secondary antibody response and mortality was 100% in these patients. 相似文献
80.
Nagarajan Ramakrishnan D. K. Daphnee Lakshmi Ranganathan S. Bhuvaneshwari 《Indian Journal of Critical Care Medicine》2014,18(3):144-148