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81.
BACKGROUND: Hepatitis C virus (HCV) infection in Egypt has reached an epidemic proportion and is associated with many extra hepatic manifestations; Glomerulonephritis (GN) is one of the most consequences of HCV infection often resulting in end stage renal disease in some cases. Detection of viral genome or particles within the kidney biopsies from HCV-infected patients has proven to be difficult. Histological characterization of renal lesions still represents a major challenge. The aim of our work was to describe the histological pattern of HCV-associated nephropathy. METHODS: Fifty Patients--out of 233--presented to Mansoura Urology and Nephrology clinic with manifestations of glomerular disease were screened for HCV antibodies by a 3rd generation ELISA test. Those tested positive for HCV antibodies were confirmed by PCR for HCV-RNA and subjected to more detailed clinical, biochemical and histological study. Kidney biopsies and in appropriate cases liver biopsies were examined by LM and electron microscopy (EM). RESULTS: Histological study of renal biopsies revealed membranoproliferative (MPGN) type 1 to be the most common lesion encountered (54%), followed by focal segmental glomerulosclerosis (FSGS) (24%), mesangioproliferative GN (18%), membranous nephropathy (MN) (4%) in that order. EM examinations of renal biopsies were successful in identifying HCV like particles in frozen renal tissue. CONCLUSION: HCV-associated glomerulopathy is a distinct category of glomerulonephritis. Results of LM showed some peculiar features. In addition, we were successful in location and detection of HCV particles in renal tissues by EM.  相似文献   
82.
BACKGROUND: The role of CD8+ T cells in the immune response to airway challenge with an allergen is poorly understood. OBJECTIVE: The aim of this study was to test the hypothesis that resident naive CD8+ T cells modulate the magnitude of CD4+ T cell-dependent allergic airway responses. METHODS: Cervical lymph node CD4+ T cells (2 x 10(6)) were harvested from ovalbumin (OVA)- or sham-sensitized rats and injected intraperitoneally into naive Brown Norway recipients. The recipients were treated with a CD8alpha mAb (OX-8) to deplete the resident CD8+ T cells (n = 12) or mouse ascites (n = 12). Two days after adoptive transfer, the recipient animals were OVA challenged, lung resistance was measured for 8 hours, and bronchoalveolar lavage (BAL) was performed. RESULTS: After OVA challenge, primed CD4-transferred CD8-depleted rats had larger early airway responses and late airway responses compared with primed CD4-transferred CD8-nondepleted rats (early airway responses: 158.6% +/- 19.2% vs 115.7% +/- 5.9%, P < .05; late airway responses: 8.5% +/- 1.7% vs 4.4% +/- 0.9%, P < .05). BAL eosinophilia was also greater (4.67% +/- 0.45% vs 2.34 +/- 0.26%, P < .01). The cells in BAL fluid expressing IL-4 mRNA were not significantly changed by CD8 depletion, but IL-5 mRNA+ cells were higher in number, and IFN-gamma mRNA+ cells were fewer in the CD8-depleted group. CONCLUSIONS: Resident CD8+ T cells downregulate the late allergic response and airway inflammation evoked by CD4+ T-cell transfers in Brown Norway rats. This downregulation does not require antigen priming.  相似文献   
83.
BackgroundThe genus Malassezia represents the dominant eukaryotic component of the skin microbial flora. There are complex interactions between this commensal and the skin, leading to various Malassezia-caused or Malassezia exacerbated skin conditions.ObjectivesTo identify Malassezia species in lesions of patients with pityriasis versicolor (PV), atopic dermatitis (AD), and seborrheic dermatitis (SD), as well as corresponding sites in healthy subjects according to the culture methods used for Malassezia species isolation.MethodsScrapings were collected from 80 patients (40 PV, 20 AD, and 20 SD) and 30 healthy subjects. For 10-14 days, specimens were cultured on Dixon's medium and Malt extract agar. Direct microscopic examination with Gram's stain, subculture on Hi chrome agar, Dixon's medium at various temperatures, Tweens assimilation, and hydrolysis of tryptophan were used for the identification of yeast isolates.ResultsThe isolation frequency of Malassezia species in healthy subjects was 13.3% for M. furfur, 10.0% for M. globosa, and 3.3% for M.sympodialis. In patients with SD, M. furfur was isolated more frequently from scalp lesions (25.0%) and then M. sympodialis (15%) and M. globosa (10%). Malassezia sympodialis was the most prevalent isolated species in AD lesions (20%), followed by M. furfur (10%). Malassezia species isolation was found to be most prevalent in PV lesions, with M. furfur being the most prevalent identified species (52.5 %), followed by unidentified species (20%).ConclusionsMalassezia species composition was similar in PV, SD, and healthy subjects, with M. furfur being the commonest isolate, while Malassezia sympodialis was the prevalent species isolated in AD lesions. Chrome agar media can be promising for the identification of Malassezia species phenotypically. However, species differentiation has to be complemented by molecular methods.  相似文献   
84.
BACKGROUND: IL-5-producing T lymphocytes increase in rat bone marrow after inhalational challenge with allergen. OBJECTIVE: To test the hypothesis that T cells migrate from the airways to the marrow, we examined the trafficking of T cells in Brown Norway rats after sensitization and challenge with ovalbumin. METHODS: Purified CD4+ T cells, harvested from cervical lymph nodes of naive and ovalbumin-sensitized donors, were labeled with carboxy fluorescein diacetate succinimidyl ester; 20 x 10(6) cells were placed in the trachea of naive or sensitized recipients under anesthesia, and 18 hours later, animals were challenged with inhaled ovalbumin. Cells were harvested 24 hours later from the bone marrow, bronchoalveolar lavage fluid, lungs, the lung blood pool of cells, lung draining lymph nodes, peripheral blood, and spleen. RESULTS: The number of carboxy fluorescein diacetate succinimidyl ester-positive cells, measured by fluorescence-activated cell sorter, in the bone marrow of ovalbumin sensitized, primed T-cell recipients was higher than either the sham-sensitized, primed T-cell recipients or sham-sensitized, naive T-cell recipients (P < .05). The number of eosinophils in both bone marrow and bronchoalveolar lavage fluid was increased in ovalbumin-sensitized, primed T-cell recipients. The expression of the T-cell chemoattractants eotaxin and IL-16, evaluated by immunohistochemistry, was higher in the bone marrow of ovalbumin-sensitized, primed T-cell recipients. CONCLUSIONS: CD4+ T cells travel from airway to bone marrow after antigen inhalation. The homing of the CD4+ T cells might be facilitated by eotaxin and IL-16 expression in the bone marrow and might contribute to the stimulation of eosinophilopoiesis after airway allergen exposure.  相似文献   
85.
ABSTRACT: BACKGROUND: Hepatitis C Virus (HCV), a single stranded RNA virus, affects millions of people worldwide and leads to chronic infection characterized by chronic inflammation in the liver and in peripheral immune cells. Chronic liver inflammation leads to progressive liver damage. MicroRNAs (miRNA) regulate inflammation (miR-155, -146a and -125b) as well as hepatocyte function (miR-122). METHODS: Here we hypothesized that microRNAs are dysregulated in chronic HCV infection. We examined miRNAs in the circulation and in peripheral monocytes of patients with chronic HCV infection to evaluate if specific miRNA expression correlated with HCV infection. RESULTS: We found that monocytes from chronic HCV infected treatment-naive (cHCV) but not treatment responder patients showed increased expression of miR-155, a positive regulator of TNFalpha, and had increased TNFalpha production compared to monocytes of normal controls. After LPS stimulation, miR-155 levels were higher in monocytes from cHCV patients compared to controls. MiR-125b, which has negative regulatory effects on inflammation, was decreased in cHCV monocytes compared to controls. Stimulation of normal monocytes with TLR4 and TLR8 ligands or HCV core, NS3 and NS5 recombinant proteins induced a robust increase in both miR-155 expression and TNFalpha production identifying potential mechanisms for in vivo induction of miR-155. Furthermore, we found increased serum miR-155 levels in HCV patients compared to controls. Serum miR-125b and miR-146a levels were also increased in HCV patients. Serum levels of miR-122 were elevated in cHCV patients and correlated with increased ALT and AST levels and serum miR-155 levels. CONCLUSION: In conclusion, our novel data demonstrate that miR-155, a positive regulator of inflammation, is upregulated both in monocytes and in the serum of patients with chronic HCV infection. Our study suggests that HCV core, NS3, and NS5 proteins or TLR4 and TLR8 ligands can mediate increased miR-155 and TNFalpha production in chronic HCV infection. The positive correlation between serum miR-155 and miR-122 increase in cHCV may be an indicator of inflammation-induced hepatocyte damage.  相似文献   
86.
Coronavirus disease 2019 (COVID‐19) is caused by SARS‐CoV‐2, a novel coronavirus strain. Some studies suggest that COVID‐19 could be an immune‐related disease, and failure of effective immune responses in initial stages of viral infection could contribute to systemic inflammation and tissue damage, leading to worse disease outcomes. T cells can act as a double‐edge sword with both pro‐ and anti‐roles in the progression of COVID‐19. Thus, better understanding of their roles in immune responses to SARS‐CoV‐2 infection is crucial. T cells primarily react to the spike protein on the coronavirus to initiate antiviral immunity; however, T‐cell responses can be suboptimal, impaired or excessive in severe COVID‐19 patients. This review focuses on the multifaceted roles of T cells in COVID‐19 pathogenesis and rationalizes their significance in eliciting appropriate antiviral immune responses in COVID‐19 patients and unexposed individuals. In addition, we summarize the potential therapeutic approaches related to T cells to treat COVID‐19 patients. These include adoptive T‐cell therapies, vaccines activating T‐cell responses, recombinant cytokines, Th1 activators and Th17 blockers, and potential utilization of immune checkpoint inhibitors alone or in combination with anti‐inflammatory drugs to improve antiviral T‐cell responses against SARS‐CoV‐2.  相似文献   
87.
ObjectiveTo assess the role of the computerized tomography (CT) scanner in cross-transmission of carbapenem-resistant Acinetobacter baumannii between hospitalized patients undergoing CT scan.MethodsA single-centre retrospective observational analysis of inpatients undergoing CT scans. Patient-unique CT scans were defined as ‘index cases’ (patients undergoing CT scan with carbapenem-resistant Acinetobacter baumannii (CRAB) colonization documented during the previous 60 days), ‘incident cases’ (patients found colonized with CRAB within 14 days following CT scan), and ‘negative cases’ (negative for CRAB before and after CT scan). CRAB acquisition was analysed by time interval between CT scan and CT scan of the prior index-case patient.ResultsAmongst 73 047 CT scans performed over 5 years, 4834 scans were performed within 12 hours of an index case. CRAB acquisition was detected in 20 patients (incident cases), including 16/2725 (5.8/1000 scans) who underwent CT scan within 6 hours of an index-case CT scan and 4/2109 (1.9/1000 scans) who had their CT scan 7–12 hours after the CT scan of an index-case patient (p 0.033, risk ratio 3.1, 95%CI 1.03–9.25). Patient characteristics for the two time periods were similar. While not the only significant predictor of CRAB acquisition (others included age and length of hospital stay prior to the CT scan), the time elapsed from an index case remained a significant predictor for CRAB acquisition on multivariate analysis (OR 0.84, 95%CI 0.74–0.95, p 0.007).ConclusionsPerforming a CT scan within 6 hours of a CT scan performed in a CRAB-positive patient was an independent predictor of CRAB acquisition, approximately tripling the risk. This probably reflects poor infection control practice in the CT suite.  相似文献   
88.

Purpose

To derive a novel formula for fetal weight estimation utilizing the linear measurement of mid-thigh soft-tissue thickness (STT).

Methods

300 women, with singleton uncomplicated pregnancy, were included in a prospective cross-sectional study. The study included four consecutive phases: phase (1) validated the original Scioscia’s formula, phase (2) derived a novel modified formula for fetal weight estimation, phase (3) validated the novel modified formula, and phase (4) evaluated the agreement between the modified and original formulae.

Results

A statistically significant correlation was found between actual fetal weight (AFW) and various sonographic biometric measurements including mid-thigh STT (r 2 = 0.656, p < 0.001), femur length (FL) (r 2 = 0.573, p < 0.001), bi-parietal diameter (BPD) (r 2 = 0.250, p < 0.001), abdominal circumference (AC) (r 2 = 0.310, p < 0.001), and estimated fetal weight (EFW) using the original Scioscia’s formula (r 2 = 0.644, p < 0.001). The modified formula showed a better signed % difference (median = ?0.41 %, IQR ?1.88 to 2.03) than the original formula (median = ?0.51 %, IQR ?2.33 to 2.00). It was noted that, using the original formula, 88.7 % of the sample had absolute error below 5 and 98.3 % of the sample had absolute error below 10 %. On the other hand, using the modified formula, 87.3 % of the sample had absolute error below 5 %, while 97.3 % had absolute error below 10 %. The agreement between the two formulae was moderate as 134 patients out of 150 had similar ranking (κ = 0.57).

Conclusion

Fetal mid-thigh SST is a simple, useful, and easily applicable parameter for fetal weight estimation.  相似文献   
89.
Although an elevated sodium concentration in human milk is suggested to be an indicator of mastitis, it is unclear whether elevated sodium concentrations are associated with immunological and inflammatory mediators in human milk. We conducted a cross-sectional study to evaluate the relationships between elevated breast milk sodium concentrations and levels of lactoferrin, lysozyme, secretory leukocyte protease inhibitor (SLPI), interleukin-8 (IL-8), and RANTES (regulated on activation normal T cell expressed and secreted) in human milk at 6 weeks postpartum in 96 lactating women in Blantyre, Malawi. Mastitis, as indicated by an elevated breast milk sodium concentration, was present in 15.6% of the women. Women with and without mastitis had respective median levels of other factors as follows: lactoferrin, 1,230 versus 565 mg/liter (P < 0.0007); lysozyme, 266 versus 274 mg/liter (P = 0.55); SLPI, 76 versus 15 μg/liter, (P < 0.0002); IL-8, 339 versus 25 ng/liter (P < 0.0001); and RANTES, 82 versus 3 ng/liter (P < 0.0001). Elevated sodium concentrations in breast milk are associated with an increase in levels of some immunological and inflammatory factors in breast milk.  相似文献   
90.
Vaccine-associated paralytic poliomyelitis (VAPP) is a rare complication of oral polio vaccine. We describe a fatal case of VAPP in an 8-month-old boy with Major Histocompatibility Class II deficiency. The isolated poliovirus was a Sabin type 2-type 1 recombinant that showed 1.4% VP1 divergence from Sabin type 2.  相似文献   
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