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11.
A minority of individuals infected with the parasite Schistosoma mansoni develops hepatic fibrosis. HLA studies in Egypt and a candidate gene search in a Sudanese population indicate that the host's genetics contribute to disease susceptibility. In an Egyptian community, 32.7% of individuals 11 years and older had significant fibrosis by WHO ultrasound criteria. Linkage to 10 candidate genes was tested using 89 affected sibling pairs from 40 pedigrees in this community. The candidates included genes that initiate fibrosis, participate in collagen synthesis, or control collagen degradation. Two to four single-nucleotide polymorphisms (SNPs) were genotyped per locus, and 188 individuals were genotyped at 48 markers. Model-free modified Haseman-Elston analysis identified linkage to a SNP in the interferon gamma receptor locus (P=0.000001). There was also weak evidence for linkage to the interleukin 13-4 region and tissue growth factor beta 1.  相似文献   
12.
Lymphocytes of thymus, spleen, peripheral blood (PB) and bone marrow (BM) collected from adult lizards, Chalcidesocellatus were cultured for 24 hr in the presence of 10?3M hydrocortisone acetate (HC) in order to assess the effect of in vitro HC on lizard T and B cell viability. The results indicated that HC induced stepwise, time-dependent mortality of the majority of thymocytes carrying T cell specific antigen(s) (TSA), 30–50% of T cells of spleen, PB and BM, and of a proportion of splenic B lymphocytes. Administration of 1 mg/g body weight HC to adult Ch. ocellatus lead to depletion of all TSA+ thymocytes. In contrast, T lymphocytes in the peripheral lymphoid compartments revealed both sensitivity and resistance to HC; similarly, B lymphocytes constituted susceptible and resistant subpopulations.  相似文献   
13.
The effect of HIV infection duration and CD4 cell count on short-term CD4 response was evaluated in treatment-naive seroconverters using logistic regression adjusted for CD4 count before highly active antiretroviral therapy (HAART) as well as for exposure category, age, sex, acute infection, and cohort. This association was also investigated in pretreated seroconverters, further adjusting for prior therapy. CD4 response (increase of >100 cells/microL at 6 months) was more likely if HAART was initiated in the first year following seroconversion (OR = 1.50 [95% CI: 1.07-2.10] compared with 2-5 years). There was no improvement in response from initiating HAART with CD4 count >350 cells/microL compared with 201 to 350 cells/microL. Below 200 cells/microL, however, the chance of a CD4 response appeared to be reduced (OR = 0.72 [95% CI: 0.40-1.28] for 0-200 cells/microL compared with 201-350 cells/microL, P = 0.26). Results were similar for pretreated individuals. Further, in pretreated individuals, a CD4 response was less likely if the CD4 nadir was lower than the pre-HAART CD4 count (OR = 0.18 [95% CI: 0.10-0.36] for >150 cells/microL difference between nadir and pre-HAART CD4 count vs. no difference, P < 0.001). Given the limitations of observational studies, particularly the inability to control for unmeasured confounders, these findings suggest that the initiation of HAART within the first year following seroconversion appears to improve short-term immunologic response. After that time, there is little to be gained in terms of short-term response from initiating HAART before reaching a CD4 count of 200 cells/microL.  相似文献   
14.
In the class II region of the major histocompatibility complex (MHC), four genes implicated in MHC class I-mediated antigen processing have been described. Two genes (TAP 1 and TAP 2) code for multimembrane-spanning ATP-binding transporter proteins and two genes (LMP 2 and LMP 7) code for subunits of the proteasome. While TAP 1 and TAP 2 have been shown to transport antigenic peptides from the cytosol into the endoplasmic reticulum, where the peptides associate with MHC class I molecules, the role of LMP 2/7 in antigen presentation is less clear. Using antigen processing mutant T2 cells that lack TAP 1/2 and LMP 2/7 genes, it was recently shown that expression of TAP 1/2 alone was sufficient for processing and presentation of the influenza matrix protein M1 as well as the minor histocompatibility antigen HA-2 by HLA-A2. To understand if presentation of a broader range of viral antigens occurs in the absence of LMP 2/7, we transfected T2 cells with TAP 1, TAP 2 and either of the H-2Kb, Db or Kd genes and tested their ability to present vesicular stomatitis vires and influenza virus antigens to virus-specific cytotoxic T lymphocytes. We found that T2 cells, expressing TAP 1/2 gene products, presented all tested viral antigens restricted through either the H-2Kb, Db or Kd class I molecules. We conclude that the proteasome subunits LMP 2/7 as well as other gene products in the MHC class II region, except from TAP 1/2, are not generally necessary for presentation of a broader panel of viral antigens to cytotoxic T cells. However, the present results do not exclude that LMP 2/7 in a more subtle way may, or in rare cases completely, affect processing of antigen for presentation by MHC class I molecules.  相似文献   
15.
Pulmonary hypertension (PH) produces strain followed by hypertrophy and later dilatation of the right ventricle (RV) and pulmonary artery. The signs and symptoms are nonspecific. There is a need for a noninvasive sensitive way to diagnose PH. The purpose of this study is to evaluate phase abnormalities in radionuclide MUGA studies of patients with referred diagnosis of PH. In a retrospective analysis of 44 patients who had a radionuclide multigated study (MUGA) and contrast ventriculography (CV), 19 had high mean pulmonary pressure (over 20 mmHg) and a high pulmonary vascular resistance index (over 2.0). In 15 patients, a delayed phase segment in the RV corresponding to the pulmonary infundibulum and pulmonary conus was noted The Pulmonary Tongue sign (PT), 12 had PH (True positive) and 3 did not (false positive) on CV. No PT was seen in the remaining 29 patients, only 7 of them had PH (False negative). The sensitivity, specificity and accuracy of the PT sign in detecting PH was 80%, 72% and 77% respectively. The number of patients was too small to calculate the correlation of the grade of PT with the severity of PH. We conclude that The Pulmonary Tongue sign on a MUGA study is clinically useful in detecting PH.This project is supported by research project MLNO13 and funded by research Council, Kuwait University  相似文献   
16.
BackgroundDespite the huge numbers of the universally produced and employed protocols, the adherence with them is still low to moderate in the healthcare settings. This study was employed to assess the attitudes of Palestinian healthcare professionals in Gaza Strip to health education and counseling on healthy behaviours protocol (WHO-PEN Protocol 2), for patients with non-communicable diseases in the Ministry of Health primary healthcare centers.MethodsThis cross-sectional study was conducted with a census sample of all governmental family physicians and nurses (n=175). The study questionnaire was developed based on Cabana theoretical framework. The Arabic version questionnaire was developed based on the cross-cultural adaptation framework. The psychometric properties of the Arabic version questionnaire was finally evaluated.ResultsThe psychometric properties of the Arabic version questionnaire showed good construct validity and internal consistency reliability. The overall adherence level to WHO-PEN Protocol 2 was 70.0, SD=6.9. The main perceived barriers were lack of incentive, patients'' factors, and lack of time. In general, most of healthcare professional respondents had a positive attitude toward the protocol, but this attitude was not predictor to protocol adherence.ConclusionThe good validity and reliability of the questionnaire can provide support for the accuracy of the study results. Varied implementation strategies targeting the major barriers derived from the study are extremely required for addressing the lack of incentives, patients'' factors and time constraints.  相似文献   
17.
BackgroundAcquired idiopathic stiffness (AIS) remains a common failure mode of contemporary total knee arthroplasties (TKAs). The present study investigated the incidence of AIS and manipulation under anesthesia (MUA) at a single institution over time, determined outcomes of MUAs, and identified risk factors associated with AIS and MUA.MethodsWe identified 9771 patients (12,735 knees) who underwent primary TKAs with cemented, modular metal-backed, posterior-stabilized implants from 2000 to 2016 using our institutional total joint registry. Mean age was 68 years, 57% were female, and mean body mass index was 33 kg/m2. Demographic, surgical, and comorbidity data were investigated via univariate Cox proportional hazard models and fit to an adjusted multivariate model to access risk for AIS and MUA. Mean follow-up was 7 years.ResultsDuring the study period, 456 knees (3.6%) developed AIS and 336 knees (2.6%) underwent MUA. Range of motion (ROM) increased a mean of 34° after the MUA; however, ROM for patients treated with MUA was inferior to patients without AIS at final follow-up (102° vs 116°, P < .0001). Significant risk factors included younger age (HR 2.3, P < .001), increased tourniquet time (HR 1.01, P < .001), general anesthesia (HR 1.3, P = .007), and diabetes (HR 1.5, P = .001).ConclusionAcquired idiopathic stiffness has continued to have an important adverse impact on the outcomes of a subset of patients undergoing primary TKAs. When utilized, MUA improved mean ROM by 34°, but patients treated with MUA still had decreased ROM compared to patients without AIS. Importantly, we identified several significant risk factors associated with AIS and subsequent MUA.Level of EvidenceLevel III, retrospective comparative study.  相似文献   
18.
BackgroundA simultaneous periprosthetic joint infection (PJI) of an ipsilateral hip and knee arthroplasty is a challenging complication of lower extremity reconstructive surgery. We evaluated the use of total femur antibiotic-impregnated polymethylmethacrylate (PMMA) bone cement spacers in the staged treatment of such limb-threatening PJIs.MethodsThirteen patients were treated with a total femur antibiotic spacer. The mean age at the time of spacer placement was 65 years. Nine patients had polymicrobial PJIs. All spacers incorporated vancomycin (3.0 g/40 g PMMA) and gentamicin (3.6 g/40 g PMMA), while 8 also included amphotericin (150 mg/40 g PMMA). Eleven spacers were biarticular. Twelve spacers were implanted through one longitudinal incision, while 8 of 12 reimplantations occurred through 2 smaller, separate hip and knee incisions. Mean follow-up after reimplantation was 3 years.ResultsTwelve (92%) patients underwent reimplantation of a total femur prosthesis at a mean of 26 weeks. One patient died of medical complications 41 days after spacer placement. At latest follow-up, 3 patients had experienced PJI recurrence managed with irrigation and debridement. One required acetabular component revision for instability. All 12 reimplanted patients retained the total femur prosthesis with no amputations. Eleven (91%) were ambulatory, and 7 (58%) remained on suppressive antibiotics.ConclusionTotal femur antibiotic spacers are a viable, but technically demanding, limb-salvage option for complex PJIs involving the ipsilateral hip and knee. In the largest series to date, there were no amputations and 75% of reimplanted patients remained infection-free. Radical debridement, antimicrobial diversity, prolonged spacer retention, and limiting recurrent soft tissue violation are potential tenets of success.Level of EvidenceIV.  相似文献   
19.
The purpose of this study is to develop and test the reliability and validity of an Egyptian version of the Children's Health Locus of Control scale. A cross sectional study design was applied using a stratified random sample of 930 students from the final two grades of primary and all grades of the preparatory schools. A further convenience sample of 120 students was selected to examine test-retest reliability of the scale. A preliminary instrument was developed and consisted of 40 statements having one of two response forms; a Yes/No format and a 4-point Likert scale format From data analysis the later format showed higher validity and reliability than the former one. Construct validity of the scale is evidenced by the factor analysis which revealed five factors (Internal, Chance, Powerful Others, Fate and Self blame) consistent with the previous theoretical model of HLC. As indicated by eta coefficient the scale and the subscales showed strong discriminating power between subjects. The known group comparison indicated a good criterion validity of the scale and the subscales. The scale showed a considerable reliability as alpha coefficient was 0.73 with test-retest reliability of 0.65. Comparison of different groups of students indicated that the scale could be used with confidence for all age groups, though it was more reliable for the preparatory phase, for private and governmental schools for males and females and for different social strata. Further testing of the developed scale is indicated among Egyptian children in different cultures.  相似文献   
20.
Both the quantity and quality of microorganisms (mold, actinomycetes and bacteria) were investigated in the air of five clean rooms indoors, outdoor air sampling was a routine work of the present study. Total viable bacterial counts were recorded in a mean value of 103 cfu/m3, whereas mold counts ranged between 102-103 cfu/m3. The highest mold counts were recorded at some places investigated such as research laboratories and a library. Moreover, the types, percentages and frequencies of occurance of viable mold were studied. Penicillium, Cladosporium and Aspergillus were the predominant mold genera. These organisms are aeroallergens. Actinomycetes were detected in low numbers compared with other organisms (range between 0-102 cfu/m3). Yellow, grey and white colour series were dominant streptomycetes. The mold and streptomycetes spore sizes were measured microscopically. The sizes of major mold spores ranged between 2.5-10 mum, whereas that of streptomycetes spores ranged between 1.2-2.5 mum. The particles < 5 mum in sizes are likely to reach the alveoli which may elicit potential risk for exposed residents. However, a low number of air microorganisms does not mean a clean and healthy environment.  相似文献   
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