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1.
OBJECTIVE: To evaluate the effectiveness of a special course on environmental health and dengue, given to primary school students and intended to promote behavioral changes in the mothers of those students that would lead to the safe handling of water, adequate disposal of trash, and control of household breeding sites of Aedes aegypti, the mosquito vector for dengue. METHODS: In the period from April to November 2002 a community field trial was carried out that included four public schools in the city of Comayaguela, Honduras. Two of the schools formed the intervention group, and the two others made up the comparison or control group. The data collection activities before and after the intervention included knowledge tests for the schoolchildren and the teachers; surveys of the knowledge, attitudes, and practices of the students' mothers; entomological surveys (systematic checking in order to find water containers, to search for mosquito larvae) in the homes of the schoolchildren; in-depth interviews with the students' mothers; observation in the classrooms; and postintervention focus group with the teachers. RESULTS: During the intervention period the largest epidemic of classical dengue ever in the history of Tegucigalpa, the capital of Honduras, occurred. That event prompted the Secretariat of Health to undertake large-scale control activities. In the two intervention schools there was a significant increase in the students' knowledge of the following three variables: dengue caused by a virus, life cycle of the vector, and reduction of breeding sites, which is the most effective measure for controlling the vector (P < 0.0001 for all those increases in knowledge). There were also significant increases in the knowledge of the same variables among the teachers in the intervention schools: dengue caused by a virus (P = 0.03), life cycle of the vector (P = 0.01), and reduction of breeding sites (P = 0.004). Reducing the number of breeding sites as being the best measure for controlling Aedes aegypti was the knowledge variable that showed the greatest change among the mothers in the intervention group (P = 0.02). The values for two of the entomological indices (the House index and the Breteau index) were better in the intervention group than in the control group, but the difference was not statistically significant. However, there was a statistically significant difference in the Breteau index values between the two control group schools and the one intervention school where the education course was implemented more adequately than in the other intervention school. CONCLUSIONS: The application of educational interventions directed to schoolchildren, as a part of a comprehensive plan for controlling Aedes aegypti, is an effective way to raise the awareness of teachers and parents with respect to the problem of dengue, and it also helps in encouraging family members to be involved in reducing breeding sites in the home. In moving to control the dengue vector, this strategy should take into consideration the involvement not only of families but also of civic and public institutions in the community. Given our results, it appears that this approach of using a special course for schoolchildren can constitute a fundamental pillar in the strategy for integrated dengue control.  相似文献   
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Type 1 diabetes (T1D) is a great medical challenge and its incidence rises rapidly. T lymphocytes and their cytokine production are supposed to play a major role in T1D development. So far, there is no potent tool to recognize the early signs of cellular auto-reactivity which leads to β-cell damage. The naïve immune system of the newborn (not yet influenced by external factors) can be used as an important model for T1D pathogenesis studies. Cord blood samples of 22 healthy neonates born at term to a diabetic parent (T1DR) and 15 newborns with no family history of any autoimmune disease (controls) were collected. Determination of 23 cytokines was performed before and after the stimulation with diabetogenic autoantigens using protein microarray. We observed lower basal production of all detected cytokines in the T1DR group – granulocyte/macrophage colony-stimulating factor (GM-CSF) (P = 0.025), growth regulated protein (GRO) (P = 0.002), GRO-α (P = 0.027), interleukin (IL)-1-α (P = 0.051), IL-3 (P = 0.008), IL-7 (P = 0.027), IL-8 (P = 0.042), monocyte chemoattractant proteins (MCP)-3 (P = 0.022), monokine-induced by IFN-γ (MIG) (P = 0.034) and regulated upon activation normal T-cell express sequence (RANTES) (P = 0.004). Exclusively lower post-stimulative levels of G-CSF (P = 0.030) and GRO-α (P = 0.04) were observed in controls in comparison with the basal levels. A significant post-stimulative decrease in G-CSF (P = 0.030) and MCP-2 (P = 0.009) levels was observed in controls in comparison with T1DR neonates. We also observed the interesting impact of the risky genotype on the protein microarray results. Protein microarray seems to be a useful tool to characterize a risk pattern of the immune response for T1D also in newborns.  相似文献   
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The risk of diabetic nephropathy is partially genetically determined. Diabetic nephropathy is linked to a gene locus on chromosome 18q22.3-q23. We aimed to identify the causative gene on chromosome 18 and to study the mechanism by which the product of this gene could be involved in the development of diabetic nephropathy. DNA polymorphisms were determined in 135 case (diabetic nephropathy) and 107 control (diabetes without nephropathy) subjects. The effect of carnosine on the production of extracellular matrix components and transforming growth factor-beta (TGF-beta) after exposure to 5 and 25 mmol/l d-glucose was studied in cultured human podocytes and mesangial cells, respectively. A trinucleotide repeat in exon 2 of the CNDP1 gene, coding for a leucine repeat in the leader peptide of the carnosinase-1 precursor, was associated with nephropathy. The shortest allelic form (CNDP1 Mannheim) was more common in the absence of nephropathy (P = 0.0028, odds ratio 2.56 [95% CI 1.36-4.84]) and was associated with lower serum carnosinase levels. Carnosine inhibited the increased production of fibronectin and collagen type VI in podocytes and the increased production of TGF-beta in mesangial cells induced by 25 mmol/l glucose. Diabetic patients with the CNDP1 Mannheim variant are less susceptible for nephropathy. Carnosine protects against the adverse effects of high glucose levels on renal cells.  相似文献   
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We developed and tested a single multiplex polymerase chain reaction (PCR) that detects enterotoxigenic, enteropathogenic, enteroinvasive, and Shiga toxin-producing Escherichia coli. This PCR is specific, sensitive, and rapid in detecting target isolates in stool and food. Because of its simplicity, economy, and efficiency, this protocol warrants further evaluation in large, prospective studies of polymicrobial substances.  相似文献   
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Though common, the exact incidence and clinical pattern of idiopathic pulmonary fibrosis (IPF) in Gulf countries are not known. The results of a four-year prospective study undertaken in two tertiary hospitals in Kuwait are presented. The mean age at diagnosis of the 52 patients studied was 55.40 +/- 11.87 years. Thirty-two (61.5%) patients were male and 22 (42.3%) were smokers. The mean duration of symptoms at diagnosis was 2.1 +/- 0.92 years. Digital clubbing was found in 34 (65%) patients. The mean FVC, TLC and TLCO were 57%, 64.4% and 55% of predicted normal, respectively. The FVC value showed a significant difference between smokers and non-smokers (p < 0.05). HRCT findings were abnormal in all patients. Typical histological and high-resolution computed tomography findings of usual interstitial pneumonia, desquamative interstitial pneumonia and non-specific interstitial pneumonia were observed. This study revealed that IPF is prevalent in Kuwait, with patterns showing some similarities to those established elsewhere. The response to treatment was not encouraging, especially in the usual interstitial pneumonia subtype.  相似文献   
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BACKGROUND: Studies examining the effects of inhaled corticosteroids (ICSs) on cortisol suppression show inconsistent results, and there is uncertainty regarding the dose-response relationship between ICSs and cortisol suppression. OBJECTIVE: To determine, using meta-analysis, the extent of cortisol suppression after administration of clinically relevant ICS doses in adults with asthma. METHODS: Database searches (MEDLINE, EMBASE, and The Cochrane Library) using appropriate indexed terms were performed to identify eligible articles for review. Articles reporting the effects of ICSs on cortisol levels in asthmatic adults, measured using the cumulative serum or plasma cortisol, morning serum or plasma cortisol, or cumulative overnight urinary free cortisol method, were identified. All available cortisol measurements were extracted. Cortisol suppression was estimated, and treatment arms were grouped into low-, medium-, and high-dose ranges according to the Global Initiative for Asthma guidelines. A multivariate model was used to determine relationships between ICS dose and cortisol suppression and to explore sources of heterogeneity among trials. RESULTS: Thirty-one studies providing information on 216 measures of cortisol suppression were included in this meta-analysis. Cortisol suppression in the low-, medium-, and high-dose groups were estimated to be 17.92% (95% confidence interval [CI], 11.08%-24.77%), 26.55% (95% CI, 17.29%-35.80%), and 36.31% (95% CI, 26.48%-46.13%), respectively. CONCLUSIONS: Statistically significant cortisol suppression was evident at low doses of ICSs and increased with dose. These results support an impact of all ICSs on endogenous cortisol levels and underscore the importance of titrating ICS doses to the minimum required to maintain symptom control.  相似文献   
8.
Morphological organization of rat hippocampal slice cultures.   总被引:6,自引:0,他引:6  
Using various histological methods, we investigated the cellular and morphological organization of rat hippocampal slice cultures. Many of the typical features of the hippocampus were retained in vitro over a long period of time. The principal cell types of the hippocampus and dentate gyrus, the pyramidal cells and granule cells, were well preserved and matured in vitro. Nonpyramidal cells and gamma-aminobutyric-acid (GABA) cells were also present in slice cultures and exhibited a strikingly similar dendritic appearance at the light microscopic level. Moreover, GABA-immunoreactive cell bodies and presynaptic terminals could be identified at the electron microscopic level; they expressed typical symmetric synaptic contacts with cell bodies and dendrites. The course of the intrinsic hippocampal fiber pathways--the mossy fibers, Schaffer collaterals, and alveus--was generally retained in vitro. Additional aberrant fiber projections could be identified. Finally, three types of nonneuronal cells could be distinguished on the basis of immunocytochemical methods.  相似文献   
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Background

Mixed phenotype acute leukemia (MPAL) represents a diagnostic and therapeutic dilemma. The European Group for the Immunological Classification of Leukemias (EGIL) scoring system unambiguously defines MPAL expressing aberrant lineage markers. Discussions surrounding it have focused on scoring details, and information is limited regarding its biological, clinical and prognostic significance. The recent World Health Organization classification is simpler and could replace the EGIL scoring system after transformation into unambiguous guidelines.

Design and Methods

Simple immunophenotypic criteria were used to classify all cases of childhood acute leukemia in order to provide therapy directed against acute lymphoblastic leukemia or acute myeloid leukemia. Prognosis, genotype and immunoglobulin/T-cell receptor gene rearrangement status were analyzed.

Results

The incidences of MPAL were 28/582 and 4/107 for children treated with acute lymphoblastic leukemia and acute myeloid leukemia regimens, respectively. In immunophenotypic principal component analysis, MPAL treated as T-cell acute lymphoblastic leukemia clustered between cases of non-mixed T-cell acute lymphoblastic leukemia and acute myeloid leukemia, while other MPAL cases were included in the respective non-mixed B-cell progenitor acute lymphoblastic leukemia or acute myeloid leukemia clusters. Analogously, immunoglobulin/T-cell receptor gene rearrangements followed the expected pattern in patients treated as having acute myeloid leukemia (non-rearranged, 4/4) or as having B-cell progenitor acute lymphoblastic leukemia (rearranged, 20/20), but were missing in 3/5 analyzed cases of MPAL treated as having T-cell acute lymphobastic leukemia. In patients who received acute lymphoblastic leukemia treatment, the 5-year event-free survival of the MPAL cases was worse than that of the non-mixed cases (53±10% and 76±2% at 5 years, respectively, P=0.0075), with a more pronounced difference among B lineage cases. The small numbers of MPAL cases treated as T-cell acute lymphoblastic leukemia or as acute myeloid leukemia hampered separate statistics. We compared prognosis of all subsets with the prognosis of previously published cohorts.

Conclusions

Simple immunophenotypic criteria are useful for therapy decisions in MPAL. In B lineage leukemia, MPAL confers poorer prognosis. However, our data do not justify a preferential use of current acute myeloid leukemia-based therapy in MPAL.  相似文献   
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