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31.
Objective  To determine the presence of unculturable bacteria using polymerase chain reaction (PCR) in infertile men with pyosperrmia. Design  Perspective clinical study. Setting  The study took place at the Department of Reproductive Medicine, Owaisi Hospital and Research Center; In vitro Fertilization Unit, Mahavir Hospital and Research Center; Center for Cellular and Molecular Biology; and Bharat Biotech Foundation, Hyderabad, India. Patients  A total of 68 infertile men and 15 donors, all with no symptoms of genito-urinary tract infections and sterile semen cultures were included in the study. Interventions  None. Main outcome measures  Screening bacteria using routine bacterial cultures and PCR based screening with universal eubarterial primers. Results  The statistical analysis of all the semen parameters in asthenazoospermic, azoospermic, ceyptazoospermic, severe oligospermic and mild oligospermic patients were found to be significant compared with the controls. All the groups were found to be significant compared with the controls (P < 0.05) except for volume and pus cells in the cryptozoospermia group. The Student’s t-test also was significant for the seminal parameters before and after treatment of 68 selected individuals with pyospermia and sterile cultures. A total of 44.11% (30/ 68) samples were collected from the negative culture of pyospermic infertile men have shown the presence of bacteria on amplification using PCR with universal eubacterial primers. The DNA was purified and sequenced. The sequences were checked for homology using DNASTAR and Ribosomal Data-Base Project II. A total of 90% of the samples have shown the nearest evolutionary relation to Pantoea P102 (AF394539) and 10% of samples have shown close relation with Burkholderia cepacia (AF042161). Conclusion  The routine bacteriological cultures were unable to detect certain bacterial species particularly with members of enterobacteriaceae family (Pantoea species). Polymerase chain reaction, when used for screening bacteria, can detect the unculturable form of bacteria in infertile men. No amplification for bacterial DNA was obtained in control samples (fertile men with sterile semen cultures.)  相似文献   
32.
Apoptosis is the best-characterized form of programmed cell death (PCD) and is of fundamental importance in tissue homeostasis. In mammalian systems, there are two major pathways that are involved in the initiation of apoptosis: the "extrinsic" death receptor pathway and the "intrinsic" mitochondrial pathway. Although these pathways act independently to initiate the death machinery in some cellular systems, in many cell types, including numerous tumor cells, there is delicate coordination and cross talk between the extrinsic and intrinsic pathways, which leads to the activation of the executioner caspase cascade. Additionally, there appears to be a fine balance between the caspase-mediated arm of death receptor signaling that engages mitochondria and the caspase-independent arm that promotes vacuole proliferation in many cells. Here, we review our current knowledge about the layers of complexity that are posed by the interactions between death receptor-induced pathways and how they influence mitochondria to regulate cellular life and death decisions.  相似文献   
33.
Role of environmental estrogens in the deterioration of male factor fertility   总被引:17,自引:0,他引:17  
OBJECTIVE: To evaluate the role of the environmental estrogens polychlorinated biphenyls (PCBs) and phthalate esters (PEs) as potential environmental hazards in the deterioration of semen parameters in infertile men without an obvious etiology. DESIGN: Randomized controlled study. SETTING: Tertiary care referral infertility clinic and academic research center. PATIENT(S): Twenty-one infertile men with sperm counts <20 million/mL and/or rapid progressive motility <25% and/or <30% normal forms without evidence of an obvious etiology and 32 control men with normal semen analyses and evidence of conception.Semen and blood samples were obtained as part of the treatment protocol. MAIN OUTCOME MEASURE(S): Evaluation of semen parameters such as ejaculate volume, sperm count, motility, morphology, vitality, osmoregulatory capacity, sperm chromatin stability, and sperm nuclear DNA integrity. RESULT(S): PCBs were detected in the seminal plasma of infertile men but not in controls, and the concentration of PEs was significantly higher in infertile men compared with controls. Ejaculate volume, sperm count, progressive motility, normal morphology, and fertilizing capacity were significantly lower in infertile men compared with controls. The highest average PCB and PE concentrations were found in urban fish eaters, followed by rural fish eaters, urban vegetarians, and rural vegetarians. The total motile sperm counts in infertile men were inversely proportional to their xenoestrogen concentrations and were significantly lower than those in the respective controls. CONCLUSION(S): PCBs and PEs may be instrumental in the deterioration of semen quality in infertile men without an obvious etiology.  相似文献   
34.
Amyloid precursor protein (APP) belongs to a conserved gene family, also including the amyloid precursor-like proteins, APLP1 and APLP2. The function of these three proteins is not yet fully understood. One of the proposed roles of APP is to promote neurite outgrowth. The aim of this study was to investigate the regulation of the expression levels of APP family members during neurite outgrowth. We observed that retinoic acid (RA)-induced neuronal differentiation of human SH-SY5Y cells resulted in increased expression of APP, APLP1 and APLP2. We also examined the effect of the NFkappaB, AP-1 and c-Jun N-terminal kinase inhibitor curcumin (diferuloylmethane) on the RA-induced expression levels of these proteins. We found that treatment with curcumin counteracted the RA-induced mRNA expression of all APP family members. In addition, we observed that curcumin treatment resulted in neurite retraction without any effect on cell viability. Surprisingly, curcumin had differential effects on the APLP protein levels in RA-differentiated cells. RA-induced APLP1 protein expression was blocked by curcumin, while the APLP2 protein levels were further increased. APP protein levels were not affected by curcumin treatment. We propose that the sustained levels of APP and the elevated levels of APLP2, in spite of the reduced mRNA expression, are due to altered proteolytic processing of these proteins. Furthermore, our results suggest that APLP1 does not undergo the same type of regulated processing as APP and APLP2.  相似文献   
35.
Recently, we defined an estimate for total branched-chain amino acids (BCAA) using the indicator amino acid oxidation technique in men fed the three BCAA (leucine, isoleucine and valine) in the proportion present in egg protein. Although egg protein is regarded as a high quality dietary protein source, it is not known whether the proportions of the three BCAA are optimal. Five men with known total BCAA requirements were restudied. Each men was studied with isoleucine, leucine or valine held constant at that individual's requirement level while the intake of the other two BCAA was reduced; one BCAA was held constant and the intake of the other two was reduced by 10 and 20% in random order. The label appearance from the oxidation of L-[13C]-phenylalanine to 13CO2 (F13CO2) in breath was monitored in response to the change in amino acid intake. When either isoleucine or leucine was held constant, and the other two BCAA reduced by 20% (valine and leucine, or valine and isoleucine, respectively) F13CO2 increased (P = 0.007, P = 0.038, respectively). We conclude that valine may be the first limiting BCAA in egg protein.  相似文献   
36.
The incidence and severity of tomato leaf curl disease (TLCD) is increasing worldwide. Here we assess the diversity and distribution within tomato producing areas of Iran of begomoviruses that cause this disease. Tomato with typical TLCD symptoms and asymptomatic weeds were collected in 2005 and 2006 and tested for the presence of begomovirus DNA using polymerase chain reaction (PCR). Analysis of cloned and sequenced PCR products revealed that both mono- and bipartite begomoviruses are associated with TLCD in Iran. Furthermore, our results confirmed the symptomless infection with mono- and bipartite begomoviruses of two weed species, Chrozophora hierosolymitana Spreng (Euphobiaceae) and Herniaria sp. (Caryophyllaceae). Eighteen Iranian begomovirus isolates were classified into two major groups and two or three subgroups according to the 5′-proximal 200 nucleotides of the coat protein (CP) gene or the N-terminal 600 nucleotides of the Rep gene. Whereas most of the monopartite isolates showed closest similarity to tomato yellow leaf curl virus-Gezira (TYLCV-Ge), the three bipartite isolates were most similar to Tomato leaf curl New Delhi virus (ToLCNDV). Mixed mono- and a bipartite begomovirus infections were detected in both tomato and C. hierosolymitana. Our results indicate that the tomato producing areas in central, southern, and southeastern Iran are threatened by begomoviruses originating from both the Mediterranean basin and the Indian subcontinent.  相似文献   
37.
Structural abnormalities of the heart are a fairly common problem, affecting more than 8 of 1,000 newborns annually in the United States. Therefore, sonographic detection of these anomalies in utero is important. It is possible to detect a high percentage of fetal cardiac anomalies through proper sonographic examination using three central views of the heart: (1) the four-chamber view; (2) the aortic outflow tract view; and (3) the pulmonary output tract view. Although average sonologists may not be able to provide a precise diagnosis for a cardiac abnormality, they are able to recognize such abnormalities in a high percentage of cases by using these three views and by answering the following questions: (1) Is the heart in a normal position? (2) Is the heart size normal? (3) Are the ventricles equal in size? (4) Is there a septal defect? (5) Are the atrioventricular valves in a normal position? and (6) Is there any abnormality of the endocardium, myocardium, or pericardium? This article presents a practical approach to the detection of fetal cardiac anomalies using the four-chamber and outflow tract views. Examples of normal anatomy and cardiac pathology are provided as well as a listing of differential diagnoses that should be reviewed when certain abnormalities are visualized.  相似文献   
38.
Objective: The objective was to review all the available published studies and reports with particular emphasis on the prevalence of opioid use and the availability of opioid treatment and harm reduction services for adults in nine countries of the Persian Gulf region. The countries are the members of the Middle and North Africa Harm Reduction Association (MENAHRA).

Methods: Data were collected by searching Pub Med, Med line and EMBASE, by reviewing the reports of the United Nations Office on Drugs and Crime (UNODC), World Health Organization (WHO), Ministries of Health (MoH) in each country, regional databases, conference presentations and annual AIDS progress reports over the last one decade.

Results: We found that with an exception of Iran, there is a paucity of research on opioid use in the region. With an exception of Iran, opioid substitution therapy (OST) is not developed but in some countries, needle and syringe programs (NSPs) are slowly emerging. Voluntary counselling and testing (VCT), HIV testing and antiretroviral therapy (ART) have been widely addressed. Non-governmental organizations (NGOs) are generally inactive. Islamic prohibitions against opioid use and stigma have prevented developing opioid treatment and harm reduction in the region.

Conclusion: An exchange of knowledge and experience on opioid use prevention, treatment and harm reduction is required between Iran and the region. Collaborations among religious leaders, mass-media, clinicians and policy makers are rigorously suggested to remove Islamic prohibitions and stigma and make opioid treatment a social norm.  相似文献   
39.
BackgroundNeisseria meningitidis is one of the most important causes of meningitis and pathogens-associated deaths in developing and developed countries. Effective anti-microbial agents are pivotal to treat and control N. meningitidis infections. The aim of the present study was to systematically review published studies on the antibiotic resistance of N. meningitidis in the last 20 years (2000–2020) in the world.MethodsPublished researches were identified through a literature search using reputable databases including PubMed, Scopus, and Web of Science. Finally, 24 studies were included for a random-effects model meta-analysis.ResultsThe overall resistance to most commonly used antibiotics such as ceftriaxone, cefotaxime, ciprofloxacin and rifampin was low, ranging from 1 to 3.4%. However, non-sensitivity to penicillin, as the first-line antibiotic against N. meningitidis, was higher (27.2%). Altogether, the resistance to the first-line antibiotics (except penicillin) is still low indicating these drugs are effective against meningococcal meningitis. We also found a significant gap between MIC and disk diffusion for evaluating resistance to antibiotics in which disk diffusion overestimate the resistance rate.ConclusionsTo properly management and prevent the spread of N. miningitidis isolates resistant antibiotics, it is necessary to monitor the pattern of antibiotic susceptibility regionally and globally using the MIC methods.  相似文献   
40.
Cancer is one of the major causes of death in the world and despite many years of research, the treatment of cancer is still a problem. Epidemiological observations and laboratory studies have indicated anticarcinogenic potential of garlic, which has been traditionally used for various human diseases around the world. In this study the cytotoxicity of garlic extract against three malignant cancer cell lines including gastric (AGS), breast (MCF-7) and colon (HT-29) and a nonmalignant cell line (L929) were evaluated by the MTT assay. The results of this study reveal MCF-7 and AGS cells were sensitive to garlic extract. Despite a many reports on inhibitory effects of garlic on cancer cell line, our data showed these effects are tumor specific and dose dependent. Further studies on animal models and humans are needed to clarify the important molecules and their mechanisms.  相似文献   
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