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71.
Rotavirus and oral cholera vaccines have the potential to reduce diarrhea-related child mortality in low-income settings and are recommended by the World Health Organization. Uptake of vaccination depends on community support, and is based on local priorities. This study investigates local perceptions of acute watery diarrhea in childhood and anticipated vaccine acceptance in two sites in the Democratic Republic of Congo. In 2010, 360 randomly selected non-affected adults were interviewed by using a semi-structured questionnaire. Witchcraft and breastfeeding were perceived as potential cause of acute watery diarrhea by 51% and 48% of respondents. Despite misperceptions, anticipated vaccine acceptance at no cost was 99%. The strongest predictor of anticipated vaccine acceptance if costs were assumed was the educational level of the respondents. Results suggest that the introduction of vaccines is a local priority and local (mis)perceptions of illness do not compromise vaccine acceptability if the vaccine is affordable.  相似文献   
72.
Matrix metalloproteinases (MMPs) play a critical role in various pathological conditions including cutaneous inflammation. Thus far, serial assessment of MMP activity in ongoing inflammation is hampered due to technical limitations. Here, we present an innovative method for longitudinal detection of MMP activity by in vivo imaging. First, we analysed skin sections from patients suffering from leucocytoclastic vasculitis (LcV) and detected a significant MMP signal via immunofluorescence staining. Then, we mimicked LcV in mice in a well‐studied model of immune complex‐mediated vasculitis (ICV). This acute inflammatory process was serially visualized in vivo using the fluorescence‐labelled MMP tracer Cy5.5‐AF443. The deposition of fluorescence‐labelled immune complexes and MMP tracer distribution was visualized repeatedly and non‐invasively by fluorescence reflectance imaging. In correlation with the presence of MMP‐2 and MMP‐9 in immunofluorescence stainings, Cy5.5‐AF443 accumulated in ICV spots in the skin of C57BL/6 mice. This tracer accumulation could also be observed in mice equipped with a dorsal skinfold chamber, where microscopic observations revealed an increased recruitment of fluorescence‐labelled leucocytes during ICV. The specificity of the MMP tracer was supported by (i) analysis of mice deficient in functional β2‐integrins (CD18?/?) and (ii) subsequent MMP immunofluorescence staining. These findings let us conclude that MMP accumulation in the acute phase of ICV depends on β2‐mediated leucocyte recruitment. In summary, we show that MMPs are involved in ICV as determined by Cy5.5‐AF443, a new optical marker to longitudinally and non‐invasively follow MMP activity in acute skin inflammation in vivo.  相似文献   
73.
Despite treatments combining surgery, radiation-, and chemotherapy, patients affected by glioblastoma (GBM) have a limited prognosis. Addition of temozolomide (TMZ) to radiation therapy is the standard therapy in clinical application, but effectiveness of TMZ is limited by the tumor''s overexpression of the DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT). The goal of this study was to use the highly specific and efficient RNA interference (RNAi) pathway to modulate MGMT expression to increase TMZ efficiency in chemotherapy resistant GBM. Using lentiviral-based anti-MGMT small hairpin RNA (shRNA) technology we observed a specific inhibition of the MGMT expression in GBM cell lines as well as in subcutaneous tumors. Tumor growth inhibition was observed following TMZ treatment of xenografts with low MGMT expression in contrast to xenografts with high MGMT expression. Bioluminescence imaging (BLI) measurements indicated that luciferase and shRNA-expressing lentiviruses were able to efficiently transduce the GBM xenografts in vivo. Treatment combining injection of a lentivirus expressing an anti-MGMT shRNA and TMZ induced a reduction of the size of the tumors, in contrast with treatment combining the lentivirus expressing the control shRNA and TMZ. Our data suggest that anti-MGMT shRNA therapy could be used in combination with TMZ chemotherapy in order to improve the treatment of resistant GBM.  相似文献   
74.
J Oral Pathol Med (2010) 39 : 435–439 Background: It is diagnostically difficult to differentiate plasmablastic lymphomas (PBLs) from plasma cell neoplasms with plasmablastic differentiation. Plasmablastic lymphomas are currently classified as ‘PBL of the oral mucosa’ and ‘PBL with plasmacytic differentiation’. Methods: Forty‐five cases of PBL were retrieved from the Departments of Oral Pathology of the Universities of Pretoria and Limpopo, South Africa. Clinical features and HIV status were recorded and each case was classified as ‘PBL of the oral mucosa type’ or as ‘PBL with plasmacytic differentiation’. Immunohistochemistry included: CD45, CD3, CD20, CD79a, CD38, CD138, MUM1, Ki‐67 and kappa and lambda light chains. Positivity was recorded based on the percentage of positive staining cells as focal (5–20%); intermediate (20–70%) or diffuse (>70%). In situ hybridization was performed for Epstein–Barr virus (EBV) and HHV‐8. Results were recorded as positive or negative. Results: All cases showed some degree of plasmacytic differentiation. All were negative for CD20 with reactive T cells detected with CD3. Diffuse and strong positive staining was found with Ki‐67 and MUM1, but variable immunoreactivity was found with CD79a, CD45, CD38 and CD138. Twenty cases (47%) showed light chain restriction. Epstein–Barr virus was detected in 44/45 cases and HHV‐8 in none. Conclusions: The morphological classification of PBLs is not valid as all cases showed some degree of plasmacytic differentiation. We propose that PBLs with light chain restriction be reclassified as ‘plasmablastic extramedullary plasmacytomas’ and managed accordingly. The rest represents true PBLs. The true nature of these neoplasms as an entity should be further investigated with molecular and genetic studies.  相似文献   
75.
76.
Indeterminate colitis: the real story   总被引:3,自引:4,他引:3  
PURPOSE: Up to one in five patients undergoing surgery for ulcerative colitis will have ambiguous histology, with features of both ulcerative colitis and Crohn's disease, and are categorized as having indeterminate colitis. We hypothesized that functional outcomes in indeterminate colitis patients undergoing ileal pouch-anal anastomosis are comparable with those of ulcerative colitis patients undergoing ileal pouch-anal anastomosis. METHODS: Physician-conducted interviews of 120 consecutive ileal pouch-anal anastomosis patients with a preoperative diagnosis of ulcerative colitis were reviewed, with a mean follow-up of 54 months. All colectomy specimens were reviewed by a single pathologist. Any changes in histologic diagnosis from ulcerative colitis to indeterminate colitis or Crohn's disease, frequency of postoperative complications, pouch function, and long-term postoperative medication usage were recorded. RESULTS: Although postoperative fistulas were more common in indeterminate colitis than ulcerative colitis (26 vs. 10 percent; P = 0.02, chi-squared), no indeterminate colitis patient required a permanent ileostomy as compared with six ulcerative colitis patients. Long-term functional results were similar. Overall, two-thirds of patients developed pouchitis. Ulcerative colitis and Crohn's disease patients were more likely to have had >3 episodes of pouchitis (58 and 72 percent) compared with indeterminate colitis patients (29 percent; P = 0.006, chi-squared). A greater number of Crohn's disease patients required maintenance oral antibiotic therapy (64 percent) to achieve satisfactory functional results compared with both indeterminate colitis and ulcerative colitis patients (20 and 28 percent; P = 0.014, chi-squared). CONCLUSIONS: Although ileal pouch-anal anastomosis patients with indeterminate colitis have more postoperative fistulas, long-term function is equal to that of ulcerative colitis patients and better than Crohn's disease patients. Ileal pouch-anal anastomosis should be offered to patients with indeterminate colitis and those with severe colitis in whom clear differentiation between indeterminate colitis and ulcerative colitis cannot be made.  相似文献   
77.
Pulmonary veins are considered to be the most common origin of the focal activity that triggers the onset of atrial fibrillation (AF). However, little is known about the importance of ectopic activity located outside the pulmonary veins. This study included 45 patients (8 women and 37 men, mean age 55 ± 12 years) with paroxysmal (n = 25) and persistent (n = 20) AF in whom multisite mapping of the right and left atria was performed using a 64-electrode basket catheter (n = 21) or a noncontact mapping system (n = 24). Spontaneous or orciprenaline-induced atrial premature complexes (APCs) were mapped. In all, 94 AF onsets from 38 distinct foci in 30 patients were observed and analyzed. Of these foci, 20 (53%) were located in pulmonary veins and 18 (47%) were located outside the pulmonary veins in other parts of the atria. In 22 patients (73%), AF was reproducibly induced by APCs from a single focus (59 episodes). In 8 patients (27%), AF originated from 2 distinct foci (35 episodes). Additionally, 20 of 30 patients (67%) who developed AF had APCs in different locations not inducing AF. APCs inducing AF had shorter coupling intervals than APCs not inducing AF (307 ± 54 vs 409 ± 76 ms, p <0.001). This study showed that 47% of ectopic foci triggering the onset of AF were located outside the pulmonary veins in extravenous parts of the left atrium and the right atrium, and 27% of patients had AF onsets of bifocal origin. These data challenge the current opinion that extrapulmonary foci play a minor role in inducing AF.  相似文献   
78.
O'Rourke MF  Adji A  Hoegler S 《Hypertension》2005,46(5):e15; author reply e15-e15; author reply e16
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79.
BACKGROUND: In rodents, the development of alcoholic liver disease (ALD) after chronic alcohol feeding was shown to depend on the activity of enzymes that are necessary for production of reactive oxygen species (ROS) in phagocytes. The aim of this study was to determine the formation of ROS by resting and challenged phagocytes of patients with different stages of ALD in the presence of ethanol concentrations commonly found in the blood of alcohol abusers. PATIENTS AND METHODS: The release of ROS and the phagocytosis of bacteria by neutrophils and monocytes obtained from 60 patients, who were categorized in three groups due to the severity of ALD, were compared to that of 28 healthy controls. ROS release by these phagocytes was measured after challenging with endotoxin and the addition of ethanol (22 and 44 mM). RESULTS: Resting neutrophils but not monocytes from patients with severe stages of ALD produced significantly more ROS than those of healthy controls. Basal values of ROS production from neutrophils correlated closely to markers of the severity of ALD. ROS formation was depressed dose-dependently by ethanol in the healthy controls but not in alcohol abusers. CONCLUSIONS: Changes in the ROS metabolism of phagocytes found in this study might contribute to both the development of ALD and the impaired immune response occurring in patients with severe ALD.  相似文献   
80.
A prospective study to evaluate the incidence of herpes zoster (HZ) as an immune restoration disease in patients with AIDS during highly active antiretroviral therapy (HAART) was conducted in a series of 115 patients diagnosed with AIDS initiated on HAART between 1 January 2000 and 31 July 2001. Of these, a single dermatomal HZ episode occurred in 14 (12%) patients within one and 15 months of HAART (median eight months). The HZ patients were similar to the non-HZ patients in age, sex, and HIV transmission risk factor, but had a more advanced disease. Compared with the baseline values, the viral loads significantly (P<0.01) decreased, while the mean CD4+ T-cell counts increased by almost four-fold (P<0.01) in both groups at the time of the HZ episode (or equivalent in non-HZ), but remained below 400/mL in the HZ patients. HZ during HAART is an immunopathological consequence of the improvement of the host immuneresponse, correlating with the beginning of immune restoration.  相似文献   
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