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41.
The role of CD16(-) and CD16(+) Mo subsets in human TB remains unknown. Our aim was to characterize Mo subsets from TB patients and to assess whether the inflammatory milieu from TB pleurisy modulate their phenotype and recruitment. We found an expansion of peripheral CD16(+) Mo that correlated with disease severity and with TNF-α plasma levels. Circulating Mo from TB patients are activated, showing a higher CD14, CD16, and CD11b expression and Mtb binding than HS. Both subsets coexpressed CCR2/CCR5, showing a potential ability to migrate to the inflammatory site. In tuberculous PF, the CD16(+) subset was the main Mo/MΦ population, accumulation that can be favored by the induction of CD16 expression in CD16(-) Mo triggered by soluble factors found in this inflammatory milieu. CD16(+) Mo in PF were characterized by a high density of receptors for Mtb recognition (DC-SIGN, MR, CD11b) and for lipid-antigens presentation (CD1b), allowing them to induce a successful, specific T cell proliferation response. Hence, in tuberculous PF, CD16(+) Mo constitute the main APC population; whereas in PB, their predominance is associated with the severity of pulmonary TB, suggesting a paradoxical role of the CD16(+) Mo subset that depends on the cellular localization.  相似文献   
42.
The established view that schizophrenia may have a favorable outcome in developing countries has been recently challenged; however, systematic studies are scarce. In this report, we describe the clinical outcome of schizophrenia among a predominantly treatment-naive cohort in a rural community setting in Ethiopia. The cohort was identified in a 2-stage sampling design using key informants and measurement-based assessment. Follow-up assessments were conducted monthly for a mean duration of 3.4 years (range 1-6 years). After screening 68 378 adults, ages 15-49 years, 321 cases with schizophrenia (82.7% men and 89.6% treatment naive) were identified. During follow-up, about a third (30.8%) of cases were continuously ill while most of the remaining cohort experienced an episodic course. Only 5.7% of the cases enjoyed a near-continuous complete remission. In the final year of follow-up, over half of the cases (54%) were in psychotic episode, while 17.6% were in partial remission and 27.4% were in complete remission for at least the month preceding the follow-up assessment. Living in a household with 3 or more adults, later age of onset, and taking antipsychotic medication for at least 50% of the follow-up period predicted complete remission. Although outcome in this setting appears better than in developed countries, the very low proportion of participants in complete remission supports the recent observation that the outcome of schizophrenia in developing countries may be heterogeneous rather than uniformly favorable. Improving access to treatment may be the logical next step to improve outcome of schizophrenia in this setting.  相似文献   
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Tuberculous pleurisy, one of the most common manifestations of extrapulmonary tuberculosis, is characterized by a T‐cell‐mediated hypersensitivity reaction along with a Th1 immune profile. In this study, we investigated functional cross‐talk among T and NK cells in human tuberculous pleurisy. We found that endogenously activated pleural fluid‐derived NK cells express high ICAM‐1 levels and induce T‐cell activation ex vivo through ICAM‐1. Besides, upon in vitro stimulation with monokines and PAMP, resting peripheral blood NK cells increased ICAM‐1 expression leading to cellular activation and Th1 polarization of autologous T cells. Furthermore, these effects were abolished by anti‐ICAM‐1 Ab. Hence, NK cells may contribute to the adaptive immune response by a direct cell‐contact‐dependent mechanism in the context of Mycobacterium tuberculosis infection.  相似文献   
45.
Parasitic helminth infection has been shown to modulate pathological inflammatory responses in allergy and autoimmune disease. The aim of this study was to examine the effects of infection with a helminth parasite, Heligmosomoides polygyrus, on type 1 diabetes (T1D) in nonobese diabetic (NOD) mice and to elucidate the mechanisms involved in this protection. H. polygyrus inoculation at 5 weeks of age protected NOD mice from T1D until 40 weeks of age and also inhibited the more aggressive cyclophosphamide-induced T1D. Moreover, H. polygyrus inoculation as late as 12 weeks of age reduced the onset of T1D in NOD mice. Following H. polygyrus inoculation of NOD mice, pancreatic insulitis was markedly inhibited. Interleukin-4 (IL-4), IL-10, and IL-13 expression and the frequency of CD4+ CD25+ FoxP3+ regulatory T cells were elevated in mesenteric and pancreatic lymph nodes. Depletion of CD4+ CD25+ T cells in vivo did not abrogate H. polygyrus-induced T1D protection, nor did anti-IL-10 receptor blocking antibody. These findings suggest that infection with H. polygyrus significantly inhibits T1D in NOD mice through CD25- and IL-10-independent mechanisms and also reduces the severity of T1D when administered late after the onset of insulitis.Helminth parasites infect about 1.5 billion people worldwide, especially in developing countries, and cause chronic infection that leads to malnutrition, anemia, impaired growth, and significant mortality. Intestinal nematode parasites can produce strong polarized Th2-type responses in mice. This immune response is characterized by eosinophilia, mucosal mast cell hyperplasia, elevated immunoglobulin E (IgE) secretion, and increased production of Th2 cytokines, such as interleukin-4 (IL-4) and IL-13. Recent studies have suggested that helminth infection can regulate infectious, allergic, or autoimmune inflammatory diseases. Helminth infection enhances susceptibility to certain infectious diseases, like tuberculosis (11, 35) and viral hepatitis (10, 17). Conversely, helminth infection is protective in murine models of asthma (19), multiple sclerosis (40), and inflammatory bowel disease (42).Type 1 diabetes (T1D) is a life-threatening disease that affects approximately 1 out of 400 children in westernized societies (18). Over the past 3 decades, the rate of T1D has increased by approximately 4% per year in both Europe and the United States (8, 12, 39). This increase in disease incidence may result in part from a dysregulated immune system due to lack of exposure to certain environmental pathogens, such as helminth parasites (5, 7, 32). Studies with nonobese diabetic (NOD) mice showed that inoculation with Trichinella spiralis, Heligmosomoides polygyrus, or Schistosoma mansoni markedly reduced the rate of T1D and suppressed lymphoid infiltration in the islets (9, 37). T1D was also prevented in NOD mice by injection of whole eggs or soluble antigens from the schistosome egg antigen or the schistosome worm antigen, but only if treatment was started at 4 weeks of age (49). Moreover, the addition of oral insulin B chain to schistosome egg antigen-treated mice augmented the induction of regulatory T cells (Tregs) that secreted IL-4, IL-10, and transforming growth factor beta (TGF-β) (27).We were interested in further examining potential mechanisms contributing to the control of T1D during infection with the intestinal nematode parasite H. polygyrus. This strictly enteric parasite triggers a potent Th2-type response without eliciting an associated Th1-type response (4). We found that H. polygyrus infection exerted significant protection against T1D in NOD mice when administered at 5 and 7 weeks of age and even when given as late as 12 weeks of age (30% protection). This was associated with reduced lymphoid infiltration in the islets and an increased frequency of CD25+ Tregs with augmented Th2-type responses, including induction of alternatively activated macrophages (AAMΦs) and IL-10 mRNA in pancreatic lymph nodes (PLN). When H. polygyrus-inoculated NOD mice were treated with cyclophosphamide (Cyp), an agent known to accelerate T1D, T1D prevention was sustained. Similarly, when H. polygyrus-inoculated NOD mice were treated with anti-CD25 monoclonal antibody (MAb) in vivo, we observed no change in insulitis between this group and those receiving a control monoclonal Ig. Furthermore, in Cyp-treated NOD mice, administration of an anti-IL-10 receptor (IL-10R) blocking MAb did not abrogate H. polygyrus-induced protection from T1D. These findings suggest that H. polygyrus inoculation suppressed T1D even after the development of insulitis and that suppression of T1D in H. polygyrus-treated NOD mice is accomplished through CD25- and IL-10-independent mechanisms.  相似文献   
46.
Chlamydia trachomatis is a global cause of blinding trachoma and sexually transmitted infections (STIs). We used comparative genomics of the family Chlamydiaceae to select conserved housekeeping genes for C. trachomatis multilocus sequencing, characterizing 19 reference and 68 clinical isolates from 6 continental/subcontinental regions. There were 44 sequence types (ST). Identical STs for STI isolates were recovered from different regions, whereas STs for trachoma isolates were restricted by continent. Twenty-nine of 52 alleles had nonuniform distributions of frequencies across regions (p<0.001). Phylogenetic analysis showed 3 disease clusters: invasive lymphogranuloma venereum strains, globally prevalent noninvasive STI strains (ompA genotypes D/Da, E, and F), and nonprevalent STI strains with a trachoma subcluster. Recombinant strains were observed among STI clusters. Single nucleotide polymorphisms (SNPs) were predictive of disease specificity. Multilocus and SNP typing can now be used to detect diverse and emerging C. trachomatis strains for epidemiologic and evolutionary studies of trachoma and STI populations worldwide.  相似文献   
47.
In this paper, we present a new approach to the segmentation and analysis of solid breast nodules in ultrasonography. We have applied computer vision techniques to segment the nodules and analyze a series of diagnostic criteria which can help discriminate malignant and benignant tumors. The segmentation is carried out in a semiautomatic way, whereas the analysis of the diagnostic criteria involves several computational methods. The techniques which we propose have provided quite satisfactory results and show the usefulness of image processing in the diagnosis through medical imaging.  相似文献   
48.
Our goal is to study the human brain anatomical network. For this, the anatomical connection probabilities (ACP) between 90 cortical and subcortical brain gray matter areas are estimated from diffusion-weighted Magnetic Resonance Imaging (DW-MRI) techniques. The ACP between any two areas gives the probability that those areas are connected at least by a single nervous fiber. Then, the brain is modeled as a non-directed weighted graph with continuous arc weights given by the ACP matrix. Based on this approach, complex networks properties such as small-world attributes, efficiency, degree distribution, vulnerability, betweenness centrality and motifs composition are studied. The analysis was carried out for 20 right-handed healthy subjects (mean age: 31.10, S.D.: 7.43). According to the results, all networks have small-world and broad-scale characteristics. Additionally, human brain anatomical networks present bigger local efficiency and smaller global efficiency than the corresponding random networks. In a vulnerability and betweenness centrality analysis, the most indispensable and critical anatomical areas were identified: putamens, precuneus, insulas, superior parietals and superior frontals. Interestingly, some areas have a negative vulnerability (e.g. superior temporal poles, pallidums, supramarginals and hechls), which suggest that even at the cost of losing in global anatomical efficiency, these structures were maintained through the evolutionary processes due to their important functions. Finally, symmetrical characteristic building blocks (motifs) of size 3 and 4 were calculated, obtaining that motifs of size 4 are the expanded version of motif of size 3. These results are in agreement with previous anatomical studies in the cat and macaque cerebral cortex.  相似文献   
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50.
INTRODUCTION: The quality of first-responder performance at the end of automated external defibrillator (AED) training may not predict the performance adequately during a real resuscitation attempt. METHODS: Between January and December 2000, we evaluated 67 resuscitation attempts in Amsterdam and surroundings, where police officers used an AED. We compared their performance with their assessment at the end of their ERC AED training course. One of the main goals of training was to deliver a shock within 90 s after switching the power on in the AED. RESULTS: We analysed 127 police officers working in 67 police-teams. The police officers had a mean age of 35 years (range 23-54 years), 73% was male. The interval between AED training and the first resuscitation attempt was a median of 4 months (range 1-13). 78% percent of the 67 teams consisted of two police officers who both were qualified as "competent" after the initial training. Successful completion of the course correlated well with good performance during a resuscitation attempt (p = 0.009). When measured switching the power on in the AED, 92% of the victims received a shock within 90 s. CONCLUSIONS: Successful training correlates well with successful performance in the field. Competence of a team may be better than competence of two separate individuals.  相似文献   
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