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1.
In this report we describe the first patient ever found to have azoospermia in association with both exceptional complex chromosomal rearrangements and microdeletions at two translocation breakpoints. A 36-year-old male who had been suffering from male factor infertility was admitted to our clinic. The patient also displayed mild dysmorphia. An analysis of the patient's semen revealed azoospermia. GTG banding revealed the presence of an exceptional complex chromosomal rearrangement involving chromosomes 1, 4, 10 and 14. Using subtelomeric FISH analysis, the patient's karyotype was designated as 46,XY,t(1;10)(q43q44;q21q26.1)(CEB108/T7+,D1S3738-;10PTEL006+,D10S2290+, D1S3738+), ins(14;4) (q31.3;q23q33)(D14S1420+; D4S3359+, D4S2930+). Array-CGH analysis revealed two microdeletions at the 4q22.3q23 and 14q31.1q31.3 chromosomal regions. We suggest that microdeletions at the 4q22.3q23 and 14q31.1q31.3 chromosomal regions associated with both an exceptional complex chromosomal rearrangement and the Homo sapiens chromosome 4 open reading frame 37 (C4orf37) gene located at the 4q22.3q23 region might be associated with male factor infertility.  相似文献   
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Complex chromosomal rearrangements are very rare chromosomal abnormalities. Individuals with a complex chromosomal rearrangement can be phenotypically normal or display a clinical abnormality. It is believed that these abnormalities are due to either microdeletions or microduplications at the translocation breakpoints or as a result of disruption of the genes located in the breakpoints. In this study we describe a 2-year-old child with mental retardation and developmental delay in whom a de novo apparently balanced exceptional complex chromosomal rearrangement was found through conventional cytogenetic analysis. Using both cytogenetic and FISH analysis, the patient's karyotype was found to be: 46,XY,der(5)t(5;7)(p15.1;7q34),t(5;8)(q13.1;8q24.1)dn. A large, clinically significant deletion which encompassed 887.69 kb was detected at the 5q12.1–5q12.3 (chr5:62.886.523–63.774.210) genomic region using array-CGH. This deleted region includes the HTR1A and RNF180 genes. This is the first report of an individual with an apparently balanced complex chromosomal rearrangement in conjunction with a microdeletion at 5q12.1–5q12.3 in which there are both mental-motor retardation and dysmorphia.  相似文献   
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The intention of this experiment was to assess the effects of different sources of dietary lipid on the fatty acid composition of the fillet and liver and the flesh quality traits of rainbow trout (Oncorhynchus mykiss) after a 70‐day feeding period. Four iso‐nitrogenous (approx. 51% crude protein) and iso‐lipidic (approx. 14% crude lipid) experimental diets were formulated. The control diet contained only fish oil (FO) as the primary lipid source. In the other three dietary treatments, fish oil was replaced by 100% (LO30/SO35/SFO35) and 70% (FO30/LO35/SO35 or FO30/SO35/SFO35) sesame oil (SO), linseed oil (LO), or sunflower oil (SFO). Triplicate groups of 40 rainbow trout (~46 g) held under similar culture conditions were hand‐fed daily to apparent satiation for 70 days. At the end of the feeding trials, no difference in growth performance among experimental groups was noted (P > 0.05). There were some differences in the proximate composition of fish fillets (P < 0.05): the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels were highest in fish fed the control diet (P < 0.05); and EPA and DHA levels in fish fed the FO30/LO35/SO35 diet were closest to the control diet (P < 0.05). In contrast, fish fed the diet containing 100% plant oils (LO30/SO35/SFO35) had the highest level of total n‐6 fatty acids in the fillet and liver. In a 12‐day refrigerated storage at 1°C the thiobarbituric acid (TBA), trimethylamin nitrogen (TMA‐N) and pH values gradually increased in all dietary groups (P < 0.05). The chemical indicators of spoilage, TBA, TMA‐N, and pH values were within the limit of acceptability for human consumption.  相似文献   
5.
Free-radical-mediated damages may play an important role during metastasis. To investigate their relevance in the metastatic process MDA levels, glutathione peroxidase (GPX) and superoxide dismutase (SOD) activities, and selenium, zinc and copper contents were determined in plasma and erythrocytes from 20 cancerous patients with metastasis and 30 age-matched controls. Significantly higher concentrations of MDA in plasma as well as in erythrocytes were found comparing to the control group. In both plasma and erythrocytes, GPX activity and selenium and zinc levels were significantly lower in patients than in controls. However, SOD activity in erythrocytes and copper levels in both plasma and erythrocytes were significantly higher in patients. The impaired antioxidant system may favor accumulation of free radicals which may induce the process of metastasis. On the other hand, it is possible that the antioxidant system is impaired as a consequence of abnormality in the antioxidative metabolisms due to the cancer process.  相似文献   
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Wower IK  Zwieb CW  Guven SA  Wower J 《The EMBO journal》2000,19(23):6612-6621
UV irradiation of an in vitro translation mixture induced cross-linking of 4-thioU-substituted tmRNA to Escherichia coli ribosomes by forming covalent complexes with ribosomal protein S1 and 16S rRNA. In the absence of S1, tmRNA was unable to bind and label ribosomal components. Mobility assays on native gels demonstrated that protein S1 bound to tmRNA with an apparent binding constant of 1 x 10(8) M(-1). A mutant tmRNA, lacking the tag coding region and pseudoknots pk2, pk3 and pk4, did not compete with full-length tmRNA, indicating that this region is required for S1 binding. This was confirmed by identification of eight cross-linked nucleotides: U85, located before the resume codon of tmRNA; U105, in the mRNA portion of tmRNA; U172 in pK2; U198, U212, U230 and U240 in pk3; and U246, in the junction between pk3 and pk4. We concluded that ribosomal protein S1, in concert with the previously identified elongation factor EF-Tu and protein SmpB, plays an important role in tmRNA-mediated trans-translation by facilitating the binding of tmRNA to ribosomes and forming complexes with free tmRNA.  相似文献   
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Emanuel syndrome results from +der(22)t(11q23;22q11). Cleft palate, ear anomalies, heart defects, genital anomalies, hypotonia, and mental retardation are the main features of the syndrome. We report a nine-year-old boy with the t(11;22)(q23;q11) chromosome, transmitted in an unbalanced fashion from his mother, and originated in the maternal grandmother's meiosis. In addition to mental retardation, hypotonia, craniofacial anomalies, and cryptorchidism, he has novel findings such as, joint hyperextensibility, left liver lobe agenesis, left sided malposition of the gallbladder and pancreas hypoplasia. This is the first report associating these features with Emanuel syndrome.  相似文献   
10.
Propolis is an agent having antimicrobial properties, however, its composition can vary depending on the area where it is collected. In the present study, the antimicrobial activity of five propolis samples, collected from four different regions in Turkey and from Brazil, against nine anaerobic strains was evaluated. Ethanol extracts of propolis (EEP) were prepared from propolis samples and we determined minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of EEP on the growth of test microorganisms by using agar dilution method. All strains were susceptible and MIC values ranged from 4 to 512 microg/ml for propolis activity. Propolis from Kazan-Ankara showed most effective MIC values to the studied microorganisms. MBC values of Kazan-Ankara EEP samples were ranged from 8 to 512 microg/ml. Death was observed within 4 h of incubation for Peptostreptococcus anaerobius and micros and Lactobacillus acidophilus and Actinomyces naeslundii, while 8 h for Prevotella oralis and Prevotella melaninogenica and Porphyromonas gingivalis, 12 h for Fusobacterium nucleatum, 16 h for Veillonella parvula. It was shown that propolis samples were more effective against Gram positive anaerobic bacteria than Gram negative ones. The organic chemical compositions of EEPs were determined by high-resolution gas chromatography coupled to mass spectrometry (GC-MS). The main compounds of EEPs were flavonoids such as pinobanksin, quercetin, naringenin, galangine, chrysin and aromatic acids such as cafeic acid. Because of increased antimicrobial resistance, propolis may be kept in mind in the treatment of oral cavity diseases.  相似文献   
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