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1.
(-)Tabersonine and (-)-11-methoxytabersonine were isolated from fruits of Melodinus reticulatus. Stems and leaves contain uvaol and eight alkaloids, five of which were previously described: (-)tabersonine, venalstonidine, kopsinine, venalstonine and its 3-oxoderivative. Three are new: 19-hydroxyvenalstonine, 19-hydroxyvenalstonidine and 3-oxovenalstonidine.  相似文献   
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Objective: The aim of the present study was to determine the accuracy of commonly used predictive formulas of resting metabolic rate (RMR) compared to measured RMR in normal and overweight young females.

Methods: In this cross-sectional study, 98 female university students aged 18–30 years with body mass index 18 to 30 kg/m2 were recruited. Anthropometric indices and body compositions were measured. RMR was measured by indirect calorimetry (FitMate, Cosmed, Rome, Italy) and estimated by 11 predictive formulas. The accuracy of the RMR formulas and mean percentage differences between estimated and measured values were calculated. Paired t test was used to compare estimated and measured RMRs.

Result: There were no significant differences between measured and estimated RMR by the 4 commonly used formulas (Mifflin, Cunningham, and World Health Organization [WHO]/Food and Agriculture Organization [FAO]). Among all of the equations, the Mifflin formula showed the lowest bias (?2.97 ± 116.43 kcal/day) at the group level and was the most accurate formula (80.23%) in normal and overweight participants. The over- and underestimated values were about 14% and 5.5%, respectively. In normal and overweight females, Mifflin was the most accurate formula, with 75.51% and 84.61% accuracy, respectively.

Conclusion: Given the current lack of a standardized formula that consistently delivers accurate results, the Mifflin formula can be recommended for estimating energy requirements in normal and overweight females in clinical practice.  相似文献   
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Aims

This study aimed to investigate the relationship between the total antioxidant capacity (TAC) and Malondialdehyde (MDA) with number of metabolic syndrome (Mets) components on the personnel working in Shahroud University of Medical Sciences.

Methods

This cross-sectional study was conducted on 167 personnel aged 30–60 years old. ATP III criteria were used to diagnose patients with MetS. Oxidative stress indicators were measured. The data was analyzed via one-way ANOVA, and Pearson and Spearman correlation coefficients.

Results

The result showed that TAC had a significant positive correlation with HDL and a significant negative correlation with abdominal obesity. In addition, there was a significant positive association between the level of MDA and age, BMI, abdominal obesity, diastolic blood pressure, triglycerides, and LDL; however, it had a negative significant correlation with HDL.

Conclusions

The measurement of TAC and MDA biomarkers can increase the early diagnosis of patients at risk of developing Mets.  相似文献   
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Objectives

Urinary tract infection caused by uropathogenic Escherichia coli (UPEC) strains is one of the most important infections in the world. UPEC encode widespread virulence factors closely related with pathogenesis of the bacteria. The purpose of this study was to evaluate the presence of different phenotypic virulence markers in UPEC isolates and determine their correlation with antibiotic resistance pattern.

Methods

UPEC isolates from patients with different clinical symptoms of UTI were collected and screened for biofilm and hemolysin production, mannose resistant, and mannose sensitive hemagglutination (MRHA and MSHA, respectively). In addition, antimicrobial resistance pattern and ESBL-producing isolates were recorded.

Results

Of the 156 UPEC isolates, biofilm and hemolysin formation was seen in 133 (85.3%) and 53 (34%) isolates, respectively. Moreover, 98 (62.8%) and 58 (37.2%) isolates showed the presence of Types 1 fimbriae (MSHA) and P fimbriae (MRHA), respectively. Our results also showed a relationship between biofilm formation in UPEC isolated from acute cystitis patients and recurrent UTI cases. Occurrence of UTI was dramatically correlated with the patients'' profiles. We observed that the difference in antimicrobial susceptibilities of the biofilm and nonbiofilm former isolates was statistically significant. The UPEC isolates showed the highest resistance to ampicillin, tetracycline, amoxicillin, and cotrimoxazole. Moreover, 26.9% of isolates were ESBL producers.

Conclusion

This study indicated that there is a relationship between the phenotypic virulence traits of the UPEC isolates, patients'' profiles, and antibiotic resistance. Detection of the phenotypic virulence factors could help to improve understanding of pathogenesis of UPEC isolates and better medical intervention.  相似文献   
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Thalassemias are the most common hereditary diseases in Iran, resulting from synthesis defects in one or more hemoglobin (Hb) subunits. The majority of patients suffer from beta-thalassemia (thal), but cases with microcytic hypochromic anemia and normal electrophoretic patterns are suspected to have alpha- or silent beta-thal. A family from the northern part of Iran, an area highly prevalent for thalassemias, was referred to us for prenatal diagnosis. The hematological data of the father indicated a pattern of beta-thal minor. Reverse hybridization analysis for the most common beta-globin mutations identified IVS-II-1 (G-->A) in the heterozygous state. The maternal laboratory data indicated a case more compatible with alpha-thal. Iron deficient anemia was ruled out, and common alpha-thal point mutations and deletions were investigated. As no mutation was detected, chain synthesis was performed and showed an alpha/beta chain ratio of 2.1, that was in the range of beta-thal minor. DNA sequencing of the entire beta-globin gene identified a heterozygous GTG-->GGG (Val-->Gly) mutation at codon 126, also known as Hb Dhonburi (Neapolis). Prenatal diagnosis of the fetal DNA showed the absence of the IVS-II-1 and codon 126 anomalies. This result demonstrates the importance of screening of individuals with mild microcytic hypochromic anemia for both alpha- and silent beta-thal mutations.  相似文献   
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Lasers in Medical Science - The combination of multiple therapeutic and diagnostic functions is fast becoming a key feature in the area of clinical oncology. The advent of nanotechnology promises...  相似文献   
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The main aim of this study was to assay the testicular H2S levels in the varicocele rat model and then to investigate the protective effects of NaHS on morphometric changes, sperm parameters, oxidative stress and apoptosis markers in rat's testis. D,L-propargylglycine (PAG) was administrated to show the effects of cystathionine γ-lyase enzyme (CSE) inhibition in the varicocele. Rats were assigned to four groups: (a) Sham, (b) varicocele, (c) varicocele + PAG and (d) varicocele + NaHS. Animals in varicocele + NaHS group received 30 µmol/L NaHS in drinking water for 56 days. In the varicocele + PAG group, animals received PAG 19 mg/kg twice a week. Morphometric assessment, oxidative stress markers, testicular H2S levels, sperm parameters, TUNEL assay and expression of Bax/Bcl2 were evaluated at the end of experiment. Testicular H2S levels were significantly decreased in varicocele group. NaHS significantly improved sperm parameters, morphometric characteristics and oxidative stress compared to varicocele group. Oxidative stress status deteriorated in the PAG group compared to the varicocele group. This study showed that a low testicular H2S level might play a critical role in male infertility. Thus, NaHS administration may be a promising treatment strategy for male infertility in varicocele. In addition, CSE may not be the only important enzyme in testicular H2S production.  相似文献   
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