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41.
Phototherapy is commonly used in the treatment of hyperbilirubinemia in newborns. No serious side effects related to phototherapy have been observed, but concerns regarding its potential to damage DNA have been expressed, based on animal or cell-culture studies. The aim of this study was to investigate, in neonates with hyperbilirubinemia, the possible relation between phototherapy and DNA damage. The study included 33 full-term newborns with non-physiological jaundice and 14 healthy newborns with physiological jaundice as controls. Phototherapy was performed with an array of six fluorescent lamps producing radiation with wavelengths of 480–520 nm at 12 μW/cm2/nm. DNA damage in lymphocytes was determined by use of the alkaline comet assay. The DNA damage increased significantly with the duration of phototherapy, as shown by measurements at 24, 48, and 72 h (P < 0.001). These findings indicate that phototherapy, widely used in neonatology units, increases DNA damage in newborns. It remains to be seen whether the genotoxic effect observed in the present study can cause any long-term health effect in phototherapy-treated infants in later life.  相似文献   
42.
SNUFER is a software for the automatic localization and generation of tables used for the presentation of single nucleotide polymorphisms (SNPs). After input of a fasta file containing the sequences to be analyzed, a multiple sequence alignment is generated using ClustalW ran inside SNUFER. The ClustalW output file is then used to generate a table which displays the SNPs detected in the aligned sequences and their degree of similarity. This table can be exported to Microsoft Word, Microsoft Excel or as a single text file, permitting further editing for publication. The software was written using Delphi 7 for programming and FireBird 2.0 for sequence database management. It is freely available for noncommercial use and can be downloaded from http://www.heranza.com.br/bioinformatica2.htm.  相似文献   
43.
Microglia are the immune cells of the CNS. Brain injury triggers phenotypic changes in microglia including regulation of surface antigens. The serine proteinase α-thrombin can induce profound changes in neural cell physiology via cleavage of proteinase-activated receptors (PARs). We recently demonstrated that pharmaceutical-grade recombinant human α-thrombin (rh-thr) induces a restricted set of proteolysis-dependent changes in microglia. CD95(Fas) is a cell-death receptor that is up-regulated in microglia by inflammatory stimuli. Here we characterized the effect of rh-thr on CD95(Fas) expression in the N9 microglial cell line. Dose–response and time course studies demonstrated maximal effects at 100 U/ml and 24 h, respectively. Regulation of expression was seen at both the surface protein and steady-state mRNA levels. The rh-thr-induced effects were mimicked by PAR1 agonist peptides and blocked by pharmacologic inhibitors selective for extracellular signal-regulated kinase 1/2 (ERK 1/2). Rh-thr also induced a rapid and sustained phosphorylation of ERK 1/2. Thrombin-induced regulation of CD95(Fas) could modulate the neuroinflammatory response in a variety of neurological disorders.  相似文献   
44.
The Familial Mediterranean Fever (FMF) shows an autosomal recessive pattern of inheritance and affects certain ethnic groups. Disease is caused by mutations in MEFV gene and more than 180 mutations have been defined in affected individuals. Current study aimed to determine the frequency-type of the mutations for MEFV gene in Sivas??middle Anatolian city. The cohort was composed of 3340 patients. MEFV gene mutations were studied by multiplex PCR based reverse hybridization stripAssay method. Patients?? clinical features were; family history: 68%, erysipelas-like erythema: 17.6%, fever: 89.9%, abdominal pain: 84.2%, peritonitis: 90.2%, arthritis: 33%, pleuritis: 14.2%, parental consanguinity: 21.2%. Current results revealed that M694V is the most frequent mutation (43.12%), followed by E148Q (20.18), M680I(G/C) (15.00%) and V726A (11.32%). The study population has a high rate of carriers and the E148Q mutation frequency was found to be highest when compared to the other regions of Turkey and other Mediterranean groups.  相似文献   
45.
Chlamydia trachomatis (CT) is the most common bacterial cause of sexually transmitted disease. High-risk human papillomavirus (HR-HPV) is considered the main etiological agent for cervical neoplasia. Evidences showed that the presence of co-infection of CT and HR-HPV plays a central role in the etiology of cervical intraepithelial neoplasia (CIN) and cervical cancer. The goals of this study were: evaluate the human papillomavirus (HPV) and CT prevalence among Brazilian women with abnormal cytology and provide the effect of this association on the severity of cervical neoplasia. The population of this study was composed by 142 women with incident histological incidence of CIN grades I, II, III or cervical cancer from Recife, Northeast of Brazil. The polymerase chain reaction method on a cervical brush specimen was used to detect both agents and the automatic sequencing method was used for HPV genotyping assay. The prevalence of HPV and CT was 100 and 24.65 %, respectively. Thirteen types of HPV were detected; HPV 16, 18, 31 and 33 were the most common. The most prevalent HPV types were HPV 16 and 18. A significant association between CT positive and HPV 16 infection was found (p < 0.0106; OR = 5.31; 95 % IC 1.59–17.67). In the study population, there was diversity of HPV infections, with high-risk types being the most common. Also, the data collected suggest that CT infection may play an important role in the natural history of HPV infection.  相似文献   
46.
47.
Visceral leishmaniasis (VL) is caused by protozoa belonging to the Leishmania donovani complex and is considered the most serious and fatal form among the different types of leishmaniasis, if not early diagnosed and treated. Among the measures of disease control stand out the management of infected dogs and the early diagnosis and appropriate treatment of human cases. Several antigens have been characterized for use in the VL diagnosis, among them are the recombinant kinesin-derived antigens from L. infantum, as rK39 and rKDDR. The main difference between these antigens is the size of the non-repetitive kinesin region and the number of repetitions of the 39 amino acid degenerate motif (6.5 and 8.5 repeats in rK39 and rKDDR, respectively). This repetitive region has a high antigenicity score. To evaluate the effect of increasing the number of repeats on diagnostic performance, we designed the rKDDR-plus antigen, containing 15.3 repeats of the 39 amino acid degenerate motif, besides the absence of the non-repetitive portion from L. infantum kinesin. Its performance was evaluated by enzyme-linked immunosorbent assay (ELISA) and rapid immunochromatographic test (ICT), and compared with the kinesin-derived antigens (rKDDR and rK39). In ELISA with human sera, all recombinant antigens had a sensitivity of 98%, whereas the specificity for rKDDR-plus, rKDDR and rK39 was 100%, 96% and 71%, respectively. When evaluated canine sera, the ELISA sensitivity was 97% for all antigens, and the specificity for rKDDR-plus, rKDDR and rK39 was 98%, 91% and 83%, respectively. Evaluation of the ICT/rKDDR-plus, using human sera, showed greater diagnostic sensitivity (90%) and specificity (100%), when compared to the IT LEISH (79% and 98%, respectively), which is based on the rK39 antigen. These results suggest that the increased presence of repetitive motifs in the rKDDR-plus protein improves the diagnostic performance of serological tests by increasing the specificity and accuracy of the diagnosis.  相似文献   
48.
Plasma triglyceride (TG) levels show a clear daily rhythm, however, thus far it is still unknown whether this rhythm results from a daily rhythm in TG production, TG uptake or both. Previous studies have shown that feeding activity affects plasma TG concentrations, but it is not clear how the daily rhythm in feeding activity affects plasma TG concentrations. In the present study, we measured plasma TG concentrations and TG secretion rates in rats at 6 Zeitgeber times to investigate whether plasma TG concentrations and TG secretion show a daily rhythm. We found that plasma TG concentrations and TG secretion show a significant day/night rhythm. Next, we removed the daily rhythm in feeding behavior by introducing a 6-meals-a-day (6M) feeding schedule to investigate whether the daily rhythm in feeding behavior is necessary to maintain the daily rhythm in TG secretion. We found that the day/night rhythm in TG secretion was abolished under 6M feeding conditions. Hepatic apolipoprotein B (ApoB) and microsomal TG transfer protein (Mttp), which are both involved in TG secretion, also lost their daily rhythmicity under 6M feeding conditions. Together, these results indicate that: (1) the daily rhythm in TG secretion contributes to the formation of a day/night rhythm in plasma TG levels and (2) a daily feeding rhythm is essential for maintaining the daily rhythm in TG secretion.  相似文献   
49.
Summary The results of a population genetic investigation on Iranians are given and compared to the results obtained on other populations from Southwestern and Southern Asia. Our total material from Iran comprises n=1020 nonrelated male and female individuals of different age. The following serum groups have been typed: Hp, Gc, Gm, and Inv. In general there exist no remarkable age or sex differences in the distribution of phenotypes and alleles (the only exception: sex differences in the distribution of the Gm (7)-phenotype). The regional distribution of phenotypes and alleles yield no marked differences, too, apart from the Invphenotypes, however. For the total material of Iran the following alleles frequencies could be calculated: Hp1=0.3045, Hp2=0.6595, Gc2=0.3405; Gm1=0.1780, Gm1,2=0.0537, Gm1,5=0.0632, Gm5=0.7051. The Gm (7)-phenotype turned out to be 36.6%; the Inv (1)-phenotype amounts to 25.6%. Comparing with other populations, especially Pakistani and Indian samples, some heterogeneity in the distribution of phenotypes and alleles within Southwestern and Southern Asia was to be demonstrated. Some distributional trends of alleles frequencies shall be mentioned here: the increase of Hp2, Gc1, and Gm1 alleles from West towards East, and in the opposite direction the decrease of Hp1, Gc2, and Gm5 alleles. Selective acting forces are supposed to be most important factors for this. D77  相似文献   
50.
Introduction of foreign genes into plant tissues via Agrobacterium tumefaciens based vectors requires specific knowledge of Agrobacterium-host compatibility. Therefore, to develop a transformation protocol for peanut (Arachis hypogaea L.), five Brazilian cultivars were screened with four wild-type A.tumefaciens strains. Successful transformation was dependent on specific bacterial strain-plant cultivar interactions and strain A281 was the most effective for tumor induction. Tumors displayed hormone autonomous growth, were opine positive and contained DNA that was homologous to the T-DNA of the inciting strain. Tumors induced on seed and seedling explants by A281 (pTD02) also expressed the reporter genes gus and npt-II contained in the binary vector. These results show that peanut is a permissive host for the acceptance of genes from specific A.tumefaciens gene vectors.Abbreviations GUS ß-glucuronidase (EC 3.2.1.31) - NPT-II neomycin phosphotransferase II (EC 2.7.1.95) - EDTA ethylene-diamine-tetracetic acid  相似文献   
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