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71.
Sulfur mustard (SM) is a highly toxic chemical warfare agent that remains a threat to human health. The immediate symptoms of pulmonary distress may develop into chronic lung injury characterized by progressive lung fibrosis, the major cause of morbidity among the surviving SM victims. Although SM has been intensely investigated, little is known about the mechanism(s) by which SM induces chronic lung pathology. Increasing evidence suggests that IL-17(+) cells are critical in fibrosis, including lung fibrotic diseases. In this study we exposed F344 rats and cynomolgus monkeys to SM via inhalation and determined the molecular and cellular milieu in their lungs at various times after SM exposure. In rats, SM induced a burst of pro-inflammatory cytokines/chemokines within 72 h, including IL-1β, TNF-α, IL-2, IL-6, CCL2, CCL3, CCL11, and CXCL1 that was associated with neutrophilic infiltration into the lung. At 2 wks and beyond (chronic phase), lymphocytic infiltration and continued elevated expression of cytokines/chemokines were sustained. TGF-β, which was undetectable in the acute phase, was strongly upregulated in the chronic phase; these conditions persisted until the animals were sacrificed. The chronic phase was also associated with myofibroblast proliferation, collagen deposition, and presence of IL-17(+) cells. At ≥30 days, SM inhalation promoted the accumulation of IL-17(+) cells in the inflamed areas of monkey lungs. Thus, SM inhalation causes acute and chronic inflammatory responses; the latter is characterized by the presence of TGF-β, fibrosis, and IL-17(+) cells in the lung. IL-17(+) cells likely play an important role in the pathogenesis of SM-induced lung injury.  相似文献   
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The number of circulating endothelial progenitor cells (EPCs) inversely correlates with cardiovascular risk and clinical outcome, and thus has been proposed as a valuable biomarker for risk assessment, disease progression, and response to therapy. However, current strategies for isolation of these rare cells are limited to complex, laborious approaches. The goal of this study was the design and validation of a disposable microfluidic platform capable of selectively capturing and enumerating EPCs directly from human whole blood in healthy and diseased subjects, eliminating sample preprocessing. We then applied the “EPC capture chip” clinically and determined EPC numbers in blood from patients with pulmonary arterial hypertension (PAH). Blood was collected in tubes and injected into polymeric microfluidic chips containing microcolumns pre-coated with anti-CD34 antibody. Captured cells were immunofluorescently stained for the expression of stem and endothelial antigens, identified and counted. The EPC capture chip was validated with conventional flow cytometry counts (r = 0.83). The inter- and intra-day reliability of the microfluidic devices was confirmed at different time points in triplicates over 1–5 months. In a cohort of 43 patients with three forms of PAH (idiopathic/heritable, drug-induced, and connective tissue disease), EPC numbers are ≈50% lower in PAH subjects vs. matched controls and inversely related to two potential disease modifiers: body mass index and postmenopausal status. The EPC capture chip (5 × 30 × 0.05 mm3) requires only 200 μL of human blood and has the strong potential to serve as a rapid bedside test for the screening and monitoring of patients with PAH and other proliferative cardiovascular, pulmonary, malignant, and neurodegenerative diseases.  相似文献   
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Background  Recurrences continue to be seen after repair of inguinal hernias. The repair of these recurrent hernias is a more complex and demanding procedure, with a high re-recurrence rate. Definite advantage has been demonstrated with endoscopic repair of these hernias. Methods  The results for this prospective study from January 2003 to December 2006 were evaluated after laparoscopic repair of 65 recurrent hernias in 61 patients. The patients were followed up for 1 year. Longer follow-up evaluation was performed for the patients who underwent surgery in the initial 3 years. Results  In this study, 37 recurrent hernias were managed using the transabdominal preperitoneal technique (TAPP) technique and 28 using the totally extraperitoneal (TEP) technique. There was no conversion and no cases of postoperative wound infection. Of the 12 metachronous hernias repaired simultaneously, 3 were occult. Seroma developed in five patients. At a follow-up assessment after 1 year, one patient had groin pain, and there was one re-recurrence. A longer follow-up period with a mean of 35.11 months failed to show any new re-recurrence. Conclusions  Laparoscopic repair of recurrent inguinal hernia is safe and effective. The morbidity and recurrence rates for the procedure are as low as for laparoscopic repair of primary hernias. Laparoscopic repair should be the gold standard for these hernias.  相似文献   
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Piper longum Linn. and Piper nigrum Linn. are conventionally used as immuno-enhancers in Indian system of traditional medicine. The underlying mechanism remains unknown. The present study was therefore, undertaken to delineate the role of piperine (major alkaloid) in cadmium (Cd) induced immuno-compromised murine splenocytes. The various biological determinants such as oxidative stress markers (reactive oxygen species and GSH), Bcl-2 protein expression, mitochondrial membrane potential, caspase-3 activity, DNA damage, splenic B and T cell population, blastogenesis and cytokines (Interleukin-2 and gamma-Interferon) were measured to ascertain its cell protective potential. Cadmium induces apoptosis at 6 h onwards. The oxidative stress markers markedly alter prior to a decline in mitochondrial membrane potential, caspase-3 activation and DNA degradation The splenic cell population was observed to change only at 18 h and the release of two cytokines was affected at 72 h. Addition of piperine in various concentrations (1, 10 and 50 microg/ml) ameliorated the above events. The highest dose of piperine could completely abrogate the toxic manifestations of cadmium and the splenic cells behaved similar to control cells. The reported free radical scavenging property of piperine and its antioxidant potential could be responsible for the modulation of intracellular oxidative stress signals. These in turn appear to mitigate the apoptotic pathway and other cellular responses altered by cadmium. The findings strongly indicate the anti-oxidative, anti-apoptotic and chemo-protective ability of piperine in blastogenesis, cytokine release and restoration of splenic cell population and is suggestive of its therapeutic usefulness in immuno-compromised situations.  相似文献   
79.
BACKGROUND/AIM: Despite bearing the main burden of HCC, prospective studies from developing countries are lacking. This prospective observational study was designed to estimate the incidence of HCC among Indian patients with hepatic cirrhosis. METHODS: Between April 2001 and November 2004, we enrolled 301 patients with liver cirrhosis. Patients found to be free of HCC using baseline abdominal ultrasound, triple-phase computed tomography (TPCT) and serum alpha-fetoprotein (AFP) levels were followed up prospectively for detection of HCC using ultrasound and AFP every 6 months, and TPCT annually. RESULTS: Among the 194 patients (mean age [SD] 45.1 [+/-13.1] years; male:female 6.1:1.0) followed up, 154 had Child's A and 40 had Child's B disease. The causes of cirrhosis were: hepatitis B-71 (36.6%), hepatitis C-54 (27.8%), dual infection with hepatitis B and C-12 (6.2%) and others including autoimmune, alcoholic and cryptogenic cirrhosis 57 (29.4%). During a cumulative follow up period of 563.4 person-years, 9 cases of HCC were detected, with an incidence rate of 1.60 per 100 person-years. CONCLUSION: In our study, the incidence of HCC among patients with liver cirrhosis was intermediate, being lower than that in Japan but higher than that reported from Europe.  相似文献   
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