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31.
32.
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   
33.
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   
34.
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   
35.
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   
36.
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   
37.

Background

Leukocyte adhesion deficiency type 1 (LAD I) is an autosomal recessive disorder caused by mutations in the ITGB2 gene, encoding the β2 integrin family. Severe recurrent infections, impaired wound healing, and periodontal diseases are the main features of disease.

Methods

In order to investigate clinical and molecular manifestations of new LAD I cases, 11 patients diagnosed in one center during 7 years were studied. Patients were screened for the ITGB2 gene mutations, using polymerase chain reaction, followed by single-strand conformation polymorphism and sequencing.

Results

The most common first presenting feature of the patients was omphalitis. The mean age of cord separation was 19.9?±?1 days. The most common clinical manifestations of the patients during the follow-up period included omphalitis, skin ulcers with poor healing, sepsis, and otitis media. During the follow-up, eight patients died. Eight homozygous changes, including seven novel mutations, were detected: two splicing (IVS4?6C>A, IVS7+1G>A), three missense (Asp128Tyr, Ala239Thr, and Gly716Ala), and three frameshift deletions (Asn282fsX41, Tyr382fsX9, and Lys636fsX22).

Conclusion

Our results indicate that different mutations underlie the development of LAD I. Definitive molecular diagnosis is valuable for genetic counseling and prenatal diagnosis. Regarding clinical presentations, it seems that omphalitis is the most consistent finding seen in LAD I infants.  相似文献   
38.
Globally at 2014, it was estimated that there was 347 million people with diabetes in which 90 percent of them were diagnosed with type 2 diabetes mellitus (T2DM). Although the association between diabetes mellitus and cancer risk was found about 100 years ago, the issue is not still clear. Many studies especially cohort and case–control studies have suggested a higher risk of cancer in patients with diabetes mainly in those with type 2 diabetes. Insulin concentration is high in these patients, and due to its mitogenic effects, it may be a possible hypotheses for higher risk of cancer in diabetic patients. Therefore, antidiabetic drugs, which are involved in insulin secretion and sensitivity, may have beneficial effects in cancer treatment. Several groups of drugs with different mechanisms of action, mostly prescribed orally, are used for the treatment of type 2 diabetes mellitus including, insulin sensitizers (thiazolidinediones), insulin secretagogues (sulfonylureas), and biguanides. In this review, the possible effects of antidiabetic drugs (biguanides, thiazolidinediones, and sulfonylureas) and some of their mechanisms for overcoming cancer will be discussed.  相似文献   
39.
In this report, we present the antenatal two‐ and three‐dimensional sonographic findings from a fetus with choledochal cyst as well as confirmatory postnatal MRI. A delayed diagnosis of choledochal cyst is common, leading to significant morbidity and mortality. Visualizing bile ducts entering a right upper quadrant cyst is pathognomonic, and early diagnosis can facilitate definitive treatment with Roux‐en‐Y hepaticojejunostomy. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43 :581–583, 2015  相似文献   
40.
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