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47,XYY syndrome is a sex chromosomal anomaly in men, which may be associated with infertility and has an incidence of 0.1% of male births. The clinical and paraclinical characteristics of men suffering from this anomaly have not been fully described. In this retrospective study, we present 37 cases of 47,XYY infertile men with sperm counts varying from normal to azoospermia, referred to the Genetics Laboratory at the Royan Institute, Iran. Thirteen individuals were mosaic and 24 non-mosaics. Non-mosaic patients were classified as azoospermic (nine cases) and normospermic/oligozoospermic men (15 cases). Two of the non-mosaic and three mosaic patients had secondary infertility. In addition, 13 of them underwent IUI, IVF or ICSI, and in seven cases, there was a biochemical pregnancy. The remaining 14 patients did not have ART. The 47,XYY syndrome is relatively unusual and can be missed clinically because of the lack of symptoms and of diverse phenotypes. Diagnosis of this aneuploidy can provide valuable data for counselling and early management of the patients who undergo fertility evaluation.  相似文献   
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Objective:To determine the patterns of resistance to first line anti-tuberculosis(TB)drugs among a collection of Mycobacterium tuberculosis(MTB)isolates from 5 provinces of Iran.Methods:A total of the 6 426 clinical specimens from patients suspected of active TB were collected from March 2010 to June 2012.All specimens were subjected for microscopy and culture tests in the TB centers of studies provinces.Drug susceptibility testing to the first line anti-TB drugs for culture positive MTB was performed on Lwenstein-Jensen(LJ)medium using proportion method.Results:Of 6 426 clinical specimens,261 were culture positive for mycobacteria,of which 252 were MTB and 9 were MOTT(mycobacteria other than tuberculosis).Of 252 MTB isolates.211(83.7%)were pan-susceptible and 41(16.3%)were resistant to at least one drug.Resistance was most common to streptomycin.30 isolates(12.0%),followed by isoniuzid,20isolates(8.0%),rifampin,15 isolates(6.0%)and ethambutol,14 isolates(5.5%).Sixteen(6.3%)MTB isolates were MDR.A clear evidence of heterogeneity amongst the 5 provinces in the proportions with resistance to one or more drugs was observed[χ~2=12.209(4 degrees of freedom),P values=0.015 9].Conclusions:The prevalence of drug resistance in this study area underscoring the need for further enforcement of TB control strategies in the Iran.Drug susceptibility testing for all TB cases to provide optimal treatment,establishing advanced diagnostic facilities for rapid detection of MDR-TB and continuous monitoring of drug resistance are recommended for prevention and control of drug-resistant TB.  相似文献   
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Tissue engineered heart valves (TEHVs) may provide a permanent solution to congenital heart valve disease by permitting somatic valve growth in the pediatric patient. However, to date, TEHV studies have focused primarily on collagen, the dominant component of valve extracellular matrix (ECM). Temporal decreases in other ECM components, such as the glycosaminoglycans (GAGs), generally decrease as cells produce more collagen under mechanically loaded states; nevertheless, GAGs represent a key component of the valve ECM, providing structural stability and hydration to the leaflets. In an effort to retain GAGs within the engineered constructs, here we investigated the utility of the protein fibrin in combination with a valve-like, cyclic flexure and steady flow (flex–flow) mechanical conditioning culture process using adult human periodontal ligament cells (PLCs). We found both fibrin and flex–flow mechanical components to be independently significant (p < 0.05), and hence important in influencing the DNA, GAG and collagen contents of the engineered tissues. In addition, the interaction of fibrin with flex–flow was found to be significant in the case of collagen; specifically, the combination of these environments promoted PLC collagen production resulting in a significant difference compared to dynamic and statically cultured specimens without fibrin. Histological examination revealed that the GAGs were retained by fibrin entrapment and adhesion, which were subsequently confirmed by additional experiments on native valve tissues. We conclude that fibrin in the flex–flow culture of engineered heart valve tissues: (i) augments PLC-derived collagen production; and (ii) enhances retention of GAGs within the developing ECM.  相似文献   
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Transcranial magnetic stimulation (TMS) is a non-invasive treatment for adolescent major depressive disorder (MDD). Existing evidence on the efficacy of TMS in adolescent MDD awaits quantitative synthesis. A systematic literature search was conducted, and data from eligible studies were synthesized using random-effects models. Treatment-covariate interactions were examined in exploratory analyses of individual-patient data (IPD). Systematic search of the literature yielded 1264 hits, of which 10 individual studies (2 randomized trials) were included for quantitative synthesis of mainly uncontrolled studies. Individual patient data (IPD) were available from five trials (all uncontrolled studies). Quantitative synthesis of aggregated data revealed a statistically significant negative overall standardized mean change (pooled SMCC = 2.04, 95% CI [1.46; 2.61], SE = 0.29, p < .001), as well as a significant overall treatment response rate (Transformed Proportion = 41.30%, 95% CI [31.03; 51.57], SE = 0.05; p < 0.001), considering data from baseline to post-treatment. Exploratory IPD analyses suggests TMS might be more effective in younger individuals and individuals with more severe depression, and efficacy might be enhanced with certain treatment modality settings, including higher number of TMS sessions, longer treatment durations, and unilateral and not bilateral stimulation. Existing studies exhibit methodological shortcomings, including small-study effects and lack of control group, blinding, and randomization—compromising the credibility of the present results. To date, two randomized controlled trials on TMS in adolescent depression have been published, and the only large-scale randomized trial suggests TMS is not more effective than sham stimulation. Future large-scale, randomized, and sham-controlled trials are warranted. Future trials should ensure appropriate selection of patients for TMS treatment and guide precision medicine approaches for stimulation protocols.

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Objective: The objective of this study is to determine if BPA exposure, as measured by maternal plasma (MP) and amniotic fluid (AF) BPA concentrations is associated with an increased risk of spontaneous preterm birth (PTB) and preterm premature rupture of membranes (pPROM).

Methods: In this nested case–control study, MP samples from women in term labor (n?=?30), preterm labor that ended with preterm delivery (n?=?25), or who had pPROM (n?=?30) and amniotic fluid samples from term labor (n=?45), preterm labor (n?=?60), and pPROM (n?=?35) were assayed for BPA by enzyme immunoassay.

Results: BPA was detectible in 100% of MP and AF samples. Women with MP BPA concentrations in the fourth quartile were at increased risk of PTB (cOR?=?4.12, 95% CI?=?1.32–12.87; aOR?=?4.78, 95% CI?=?1.14–20) but not pPROM. High (fourth quartile) AF BPA values also tended to increase the risk of pPROM (cOR?=?2.47, 95% CI?=?0.96–6.37) but results were not statistically significant.

Conclusions: Increased BPA concentration is associated with an increased risk for PTB or pPROM depending on the maternal–fetal compartment(s) affected. High MP plasma BPA concentrations are associated with PTB with intact membranes but high AF BPA concentrations may weakly be associated with pPROM.  相似文献   
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Purpose

The aim of this research work was to explore the possibility of providing multifunctional oral insulin delivery system by conjugating several types of dipeptides on chitosan and trimethyl chitosan to be used as drug carriers.

Method

Conjugates of Glycyl-glycine and alanyl-alanine of chitosan and trimethyl chitosan (on primary alcohol group of polymer located on carbon 6) were synthesized and nanoparticles containing insulin were prepared for oral delivery. Preparation conditions of nanoparticles were optimized and their performance to enhance the permeability of insulin as well as cytotoxicity of nanoparticles in Caco-2 cell line was evaluated. To evaluate the efficacy of orally administered nanoparticles, nanoparticles with the most permeability enhancing ability were studied in male Wistar rats as animal model by measuring insulin and glucose Serum levels.

Result

Structural study of all the conjugates by infrared spectroscopy and nuclear magnetic resonance confirmed the successful formation of the conjugates with the desirable substitution degree. By optimizing preparation conditions, nanoparticles with expected size (157.3–197.7?nm), Zeta potential (24.35–34.37?mV), polydispersity index (0.365–0.512), entrapment efficiency (70.60–86.52%) and loading capacity (30.92–56.81%), proper morphology and desirable release pattern were obtained. Glycyl-glycine and alanyl-alanine conjugate nanoparticles of trimethyl chitosan showed 2.5–3.3 folds more effective insulin permeability in Caco-2 cell line than their chitosan counterparts. In animal model, oral administration of glycyl-glycine and alanyl-alanine conjugate nanoparticles of trimethyl chitosan demonstrated reasonable increase in Serum insulin level with relative bioavailability of 17.19% and 15.46% for glycyl-glycine and alanyl-alanine conjugate nanoparticles, respectively, and reduction in Serum glucose level compared with trimethyl chitosan nanoparticles (p?<?0.05).

Conclusion

It seems that glycyl-glycine and alanyl-alanine conjugate nanoparticles of trimethyl chitosan have met the aim of this research work and have been able to orally deliver insulin with more than one mechanism in animal model. Hence, they are promising candidates for further research studies.  相似文献   
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