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21.
Zali MR Mehr AJ Rezaian M Meamar AR Vaziri S Mohraz M 《Japanese journal of infectious diseases》2004,57(6):268-270
Parasites are important enteric pathogens among patients with human immunodeficiency virus (HIV) infection. There have been very few reports on the prevalence of intestinal parasites among such patients in Iran. To determine the prevalence of intestinal parasites among HIV-positive individuals, we collected single stool samples and analyzed them for detection of various intestinal parasites from 206 HIV-positive individuals with different immune status visited in different medical centers in Iran. The data were tested for statistical significance with chi(2) and Mann-Whitney U tests. The overall prevalence of intestinal parasites was 18.4% (95%CI: 13.7, 24.3). More specifically, the following parasites were identified: Giardia lamblia (7.3%), Blastocystis hominis (4.4%), Entamoeba coli (3.9%), and Cryptosporidium parvum (1.5%). Other parasites observed included Strongyloides stercoralis and Hymenolepis nana in two cases and Dicrocoelium dendriticum in one. Of the 38 patients who tested positive for intestinal parasites, 15 (39.2%) had diarrhea. Intestinal parasites were significantly more common among patients with diarrhea than those without (P < 0.001). Further, CD4 counts were significantly lower among individuals with diarrhea than those without (P < 0.001). This study highlights the importance of testing for intestinal parasites among Iranian HIV-positive patients, especially those with low immunity presenting with diarrhea. 相似文献
22.
Multilayer three-dimensional super resolution imaging of thick biological samples 总被引:1,自引:0,他引:1
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Alipasha Vaziri Jianyong Tang Hari Shroff Charles V. Shank 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(51):20221-20226
Recent advances in optical microscopy have enabled biological imaging beyond the diffraction limit at nanometer resolution. A general feature of most of the techniques based on photoactivated localization microscopy (PALM) or stochastic optical reconstruction microscopy (STORM) has been the use of thin biological samples in combination with total internal reflection, thus limiting the imaging depth to a fraction of an optical wavelength. However, to study whole cells or organelles that are typically up to 15 μm deep into the cell, the extension of these methods to a three-dimensional (3D) super resolution technique is required. Here, we report an advance in optical microscopy that enables imaging of protein distributions in cells with a lateral localization precision better than 50 nm at multiple imaging planes deep in biological samples. The approach is based on combining the lateral super resolution provided by PALM with two-photon temporal focusing that provides optical sectioning. We have generated super-resolution images over an axial range of ≈10 μm in both mitochondrially labeled fixed cells, and in the membranes of living S2 Drosophila cells. 相似文献
23.
Mohammadhassan JOKAR Zohreh MOOSSAVI Azam Vaziri FARD 《International journal of rheumatic diseases》2007,10(2):117-120
Aim: To study the response of cortisol to insulin‐induced hypoglycemia in patients with active rheumatoid arthritis (RA). Methods: We measured the response of cortisol to insulin‐induced hypoglycemia (0.15 µ/kg) in 10 patients (6 female, 4 male) with active RA and 10 (6 female, 4 male) healthy controls. All patients had never received glucocorticoids before the study. The cortisol concentration was assessed by radioimmunoassay. Results: The mean age was 47.3 years (± 14.2 years) in patients and 43.5 years (± 10.6 years) in control subjects. The mean disease duration was 66.3 months (range 12–120). The basal serum levels of cortisol in patients with RA were not significantly different from those of controls. Although the mean serum cortisol levels after insulin‐induced hypoglycemia were lower in patients with RA than controls in all samples, the significant difference was seen only in the samples 60 min after insulin injection (18.59 vs. 24.28 µg/dL, P = 0.041). Conclusion: Our findings suggest that active RA is associated with dysfunction of the hypothalamic–pituitary‐adrenal axis. 相似文献
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25.
R C Allsopp H Vaziri C Patterson S Goldstein E V Younglai A B Futcher C W Greider C B Harley 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(21):10114-10118
When human fibroblasts from different donors are grown in vitro, only a small fraction of the variation in their finite replicative capacity is explained by the chronological age of the donor. Because we had previously shown that telomeres, the terminal guanine-rich sequences of chromosomes, shorten throughout the life-span of cultured cells, we wished to determine whether variation in initial telomere length would account for the unexplained variation in replicative capacity. Analysis of cells from 31 donors (aged 0-93 yr) indicated relatively weak correlations between proliferative ability and donor age (m = -0.2 doubling per yr; r = -0.42; P = 0.02) and between telomeric DNA and donor age (m = -15 base pairs per yr; r = -0.43; P = 0.02). However, there was a striking correlation, valid over the entire age range of the donors, between replicative capacity and initial telomere length (m = 10 doublings per kilobase pair; r = 0.76; P = 0.004), indicating that cell strains with shorter telomeres underwent significantly fewer doublings than those with longer telomeres. These observations suggest that telomere length is a biomarker of somatic cell aging in humans and are consistent with a causal role for telomere loss in this process. We also found that fibroblasts from Hutchinson-Gilford progeria donors had short telomeres, consistent with their reduced division potential in vitro. In contrast, telomeres from sperm DNA did not decrease with age of the donor, suggesting that a mechanism for maintaining telomere length, such as telomerase expression, may be active in germ-line tissue. 相似文献
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27.
Howard I. Pryor II Adam Singleton Elissa Lin Paul Lin Khashayar Vaziri 《Surgical endoscopy》2013,27(3):843-848
Background
In the morbidly obese population that undergoes bariatric surgery, venous thromboembolism (VTE) is the leading cause of morbidity and mortality. Certain factors place a patient at higher risk for VTE. No consensus exists on VTE screening or prophylaxis for the high-risk patient. This report describes the results of a survey on VTE screening and prophylaxis patterns in high-risk bariatric surgery.Methods
Members of the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) were queried on factors that identified bariatric patients as high risk for VTE and on routine screening and prophylaxis practices. This included mechanical and chemical prophylaxis, duration of therapy, and use of inferior vena cava (IVC) filters.Results
Of the 385 surgeons who responded to the survey, 81 % were bariatric surgeons, and the majority managed more than 50 cases annually. One or more of the following risk factors qualified patients as high risk: history of VTE, hypercoagulable status, body mass index (BMI) exceeding 55 kg/m2, partial pressure of arterial oxygen (PaO2) lower than 60 mmHg, and severe immobility. Preoperative screening of patients for VTE was practiced routinely by 56 % of the surgeons, and 92.4 % used preoperative chemoprophylaxis. The most common agent used preoperatively was heparin (48 %), and Lovenox was most commonly used postoperatively (49 %). Whereas 48 % of the patients discontinued chemoprophylaxis at discharge, 43 % continued chemoprophylaxis as outpatients, and 47 % routinely screened for VTE postoperatively. Use of IVC filters was routine for 28 % of the patients, who most commonly removed them after 1–3 months.Conclusions
This study describes current practice patterns of VTE screening and prophylaxis in high-risk bariatric surgery. Nearly all surgeons agree on risk factors that qualify patients as high risk, but only half routinely screen patients preoperatively. Preoperative VTE chemoprophylaxis is used by nearly all surgeons, but the duration of therapy varies. Use of IVC filters is not routine, and postoperative screening was performed by less than half of the respondents. An understanding of current practice patterns yields insight into the rates of VTE and shows variability in the need for evidence-based prophylaxis and standardized screening. 相似文献28.
M.K. Mirahmadi C.H. Barton N.D. Vaziri S. Gordon N. Penera 《The journal of spinal cord medicine》2013,36(2):36-40
ABSTRACTBoth end stage renal disease (ESRD) and spinal cord injury (SCI) represent major disabling conditions that may be associated with protein-calorie malnutrition (PCM). The prevalence of PCM in ESRD, however, remains unknown, and virtually no data exist regarding the status of PCM in patients with both SCI and ESRD. In this study we evaluated 23 ambulatory-ESAD patients and 11 SCI-ESRD patients utilizing a range of parameters recommended for assessing nutritional status in ESRD. Based on these parameters, our results show evidence for PCM in a substantial proportion of both groups. When the two groups were compared, however, the frequency and severity of PCM were significantly greater in the SCI-ESRD patients. Important factors felt to adversely influence nutritional status in the SCI-ESRD patients were intercurrent infection and amyloidosis that were found to frequently complicate this setting. It is also probable that the combined effects of PCM and ESRD significantly predispose these patients to further infection, establishing a vicious cycle. 相似文献
29.
Marco Milone Matteo ND Di Minno Paolo Bianco Guido Coretti Mario Musella Francesco Milone 《International wound journal》2016,13(3):349-353
Pilonidal sinus surgery could, as of now, be considered a surgery tailored more to the surgeon than to the patient. In an attempt to give to surgeons an objective instrument of decision, we have evaluated which variables could be considered predictive of postoperative complications after pilonidal sinus surgery. A prospective electronic database of all patients treated for sacrococcygeal pilonidal disease was analysed. Sex, age, obesity, smoking, recurrent disease, the presence of multiple orifices and the distance between the most lateral orifice and midline were recorded and correlated with the occurrence of postoperative complications (infection and recurrence); 1006 patients were evaluated. Excision with primary mid‐line closure was performed on all the patients. Mean follow‐up was 7·3 ± 3·6 years. A total of 158 patients with postoperative complications (infection and/or recurrence) were recorded during this period. A multivariate analysis showed that, after adjusting for major clinical and demographic characteristics, only a recurrent disease [odds ratio (OR): 3·41, 95% confidence interval (CI): 1·89–6·15, P < 0·001] and the distance of lateral orifice from midline (OR: 26·3, 95% CI: 12·2–56·7, P < 0·001) were independent predictors of overall postoperative complications. Focussing on the distance from midline, the receiver operative characteristic (ROC) analysis showed that the distance of lateral orifice from midline predicted 79·2% of complications and the Youden's test identified the best cut‐off as 2·0 cm for this variable. An evidence‐based tool for deciding on the type of surgical intervention could be developed and validated by further ad hoc prospective studies evaluating our results in comparison to other different types of surgical techniques. Our results support the use of these variables as an effective way to tailor pilonidal sinus surgery to the patient, so as to obtain the best results in patient care. 相似文献
30.