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1.
Molecular Biology Reports - Teratozoospermia is a condition related to poor morphologically normal sperm count below the lower reference limit, which could hinder natural conception. Single...  相似文献   

2.
Zhang AM  Bandelt HJ  Jia X  Zhang W  Li S  Yu D  Wang D  Zhuang XY  Zhang Q  Yao YG 《PloS one》2011,6(10):e26511
Mitochondrial transfer RNA (mt-tRNA) mutations have been reported to be associated with a variety of diseases. In a previous paper that studied the mtDNA background effect on clinical expression of Leber''s hereditary optic neuropathy (LHON) in 182 Chinese families with m.11778G>A, we found a strikingly high frequency (7/182) of m.593T>C in the mitochondrially encoded tRNA phenylalanine (MT-TF) gene in unrelated LHON patients. To determine the potential role of m.593T>C in LHON, we compared the frequency of this variant in 479 LHON patients with m.11778G>A, 843 patients with clinical features of LHON but without the three known primary mutations, and 2374 Han Chinese from the general populations. The frequency of m.593T>C was higher in LHON patients (14/479) than in suspected LHON subjects (12/843) or in general controls (49/2374), but the difference was not statistically significant. The overall penetrance of LHON in families with both m.11778G>A and m.593T>C (44.6%) was also substantially higher than that of families with only m.11778G>A (32.9%) (P = 0.083). Secondary structure prediction of the MT-TF gene with the wild type or m.593T>C showed that this nucleotide change decreases the free energy. Electrophoretic mobility of the MT-TF genes with the wild type or m.593T>C transcribed in vitro further confirmed the change of secondary structure in the presence of this variant. Although our results could suggest a modest synergistic effect of variant m.593T>C on the LHON causing mutation m.11778G>A, the lack of statistical significance probably due to the relatively small sample size analyzed, makes necessary more studies to confirm this effect.  相似文献   

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The electrical stimulation model of thrombus formation was tested on rabbit carotid artery and adapted to sheep left circumflex coronary artery (LCCA). LCCA blood flow, mean arterial pressure (MAP), heart rate (HR) and ECG were monitored continuously and arterial and coronary venous blood samples were taken for radioimmunoassay of thromboxane B2. Stimulation of the LCCA mimicked acute myocardial infarction; reduction in LCCA blood flow preceded a fall in MAP and appearance of ECG abnormalities. Thromboxane B2 levels rose by 126% 35 min after stimulation. These findings support the proposal by other authors that thromboxane plays an important role in the pathogenesis of acute myocardial infarction.  相似文献   

5.
Mutations in the human DJ-1/PARK7 gene are associated with familial Parkinson’s disease. DJ-1 belongs to a large, functionally diverse family with homologues in all biological kingdoms. Several activities have been demonstrated for DJ-1: an antioxidant protein, a redox-regulated molecular chaperone and a modulator of multiple cellular signalling pathways. The majority of functional studies have focussed on human DJ-1 (hDJ-1), but studies on DJ-1 homologues in Drosophila melanogaster, Caenorhabditis elegans, Dugesia japonica and Escherichia coli also provide evidence of a role for DJ-1 as an antioxidant. Here, we show that dehydration is a potent inducer of a dj-1 gene in the anhydrobiotic nematode Panagrolaimus superbus. Our secondary structure and homology modelling analyses shows that recombinant DJ-1 protein from P. superbus (PsuDJ-1.1) is a well-folded protein, which is similar in structure to the hDJ-1. PsuDJ-1.1 is a heat stable protein; with T1/2 unfolding transition values of 76 and 70 °C obtained from both circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR) measurements respectively. We found that PsuDJ-1.1 is an efficient antioxidant that also functions as a ‘holdase’ molecular chaperone that can maintain its chaperone function in a reducing environment. In addition to its chaperone activity, PsuDJ-1.1 may also be an important non-enzymatic antioxidant, capable of providing protection to P. superbus from oxidative damage when the nematodes are in a desiccated, anhydrobiotic state.

Electronic supplementary material

The online version of this article (doi:10.1007/s12192-014-0531-6) contains supplementary material, which is available to authorized users.  相似文献   

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An endo-β-1,3(4)-glucanase gene, Agl9A, was cloned from Alicyclobacillus sp. A4 and expressed in Pichia pastoris. Its deduced amino acid sequence shared the highest identity (48%) with an endo-β-1,4-glucansae from Alicyclobacillus acidocaldarius that belongs to family 9 of the glycoside hydrolases. The purified recombinant Agl9A exhibited relatively wide substrate specificity, including lichenan (109%), barley β-glucan (100%), CMC-Na (15.02%), and laminarin (6.19%). The optimal conditions for Agl9A activity were pH 5.8 and 55°C. The enzyme was stable over a broad pH range (>60% activity retained after 1-h incubation at pH 3.8–11.2) and at 60°C (>70% activity retained after 1-h incubation). Agl9A was highly resistant to various neutral proteases (e.g., trypsin, α-chymotrypsin, and collagenase) and Neutrase 0.8L (Novozymes), a protease widely added to the mash. Under simulated mashing conditions, addition of Agl9A (20 U/ml) or a commercial xylanase (200 U/ml) reduced the filtration rate (26.71% and 20.21%, respectively) and viscosity (6.12% and 4.78%, respectively); furthermore, combined use of Agl9A (10 U/ml) and the xylanase (100 U/ml) even more effectively reduced the filtration rate (31.73%) and viscosity (8.79%). These characteristics indicate that Agl9A is a good candidate to improve glucan degradation in the malting and brewing industry.  相似文献   

8.

Chronic infection with HBV has been reported to be associated with the development of HCC. The inflammation mounted by cytokine-mediated immune system plays an important role in the pathogenesis of HBV-associated HCC. IL-18 is a pro-inflammatory cytokine whose role in the development of HBV-associated chronic to malignant disease state has not been much studied. The present study was conceived to determine the role of genetic polymorphisms in IL-18, serum levels of IL-18, and expression level of its signal transducers in the HBV disease progression. A total of 403 subjects were enrolled for this study including 102 healthy subjects and 301 patients with HBV infection in different diseased categories. Polymorphism was determined using PCR–RFLP. Genotypic distributions between the groups were compared using odd’s ratio and 95% CI were calculated to express the relative risk. Circulating IL-18 levels were determined by ELISA. Expression levels of pSTAT-1 and pNF?B was determined by western blotting. In case of IL-18(??607C?>?A), the heterozygous genotype (CA) was found to be a protective factor while in case of IL-18(??137G?>?C) the heterozygous genotype (GC) acted as a risk factor for disease progression from HBV to HCC. Moreover, serum IL-18 levels were significantly increased during HBV disease progression to HCC as compared to controls. Also the levels of activated signal transducers (pSTAT-1 and pNF-κB) of IL-18 in stimulated PBMCs were significantly increased during HBV to HCC disease progression. These findings suggest that IL-18 has the potential to act as a biomarker of HBV-related disease progression to HCC.

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9.
BackgroundIL-18, a pleiotropic, pro-inflammatory cytokine that plays a major role in innate as well as acquired immunity, has been implicated in asthma etiology and this is the first study investigating the role of IL-18 ?137G/C (rs 187238) promoter polymorphism in asthma pathogenesis in a North Indian population.MethodsA pilot study was conducted with a total of 824 subjects, out of which 410 were asthma patients including 323 patients suffering from allergic rhinitis and 414 healthy controls from regions of North India. Tetra-Primer Amplification Refractory Mutation System Polymerase Chain Reaction (Tetra-Primer ARMS PCR) was used for genotyping the IL-18 ?137G/C polymorphism.ResultsWhile the homozygous wild (GG) genotype was equally prevalent in asthma patients as well as control subjects (70.0%), the homozygous mutant (CC) genotype was more prevalent among the controls (8.0%) than in asthma patients (3.4%), which yielded a significant protection or decreased risk towards asthma. Statistical analysis revealed Odds Ratio (OR) = 0.43 (95% CI = 0.21–0.85), Chi2 (χ2) = 6.93 and p-value = 0.008 (p < 0.005). Moreover, a few asthma phenotypic traits also revealed significant protective associations with the polymorphism.ConclusionsThe IL-18 ?137G/C polymorphism confers a significant protection from asthma in the studied North Indian population. This is the first study to report the protective association of the polymorphism with the disease.  相似文献   

10.
《Genomics》2020,112(1):669-676
This investigation profiled circulating serum concentrations of microRNAs (miRNAs) in premature cardiovascular disease (CVD) patients screened for the 677C > T polymorphism in methylenetetrahydrofolate reductase (MTHFR), a risk factor for hypertension. Serum samples from 75 premature CVD patients of known MTHFR genotype were analysed for CVD-related miRNA expression, to identify those that were associated with blood pressure. Samples were collected at baseline and following intervention with riboflavin as part of a randomized controlled trial. In patients with the MTHFR 677TT genotype, expression of miR-199a-5p in serum was inversely correlated with hypertension at baseline, and with change in blood pressure in TT genotype patients who responded to riboflavin intervention. These correlations were not observed in MTHFR 677CC genotype patients. In vitro experiments and in silico data analysis provided evidence that miR-199a-5p targets SMAD4. This is the first study to link miR-199a-5p expression with hypertension in a genetically at-risk cohort of premature CVD patients.  相似文献   

11.
Metabolomics - Studies investigating crop resistance to abiotic and biotic stress have largely focused on plant responses to singular forms of stress and individual biochemical pathways that only...  相似文献   

12.
Medulloblastoma is the most common malignant brain tumor in children and is associated with a poor outcome. We were interested in gaining further insight into the potential of targeting the human kinome as a novel approach to sensitize medulloblastoma to chemotherapeutic agents. A library of small interfering RNA (siRNA) was used to downregulate the known human protein and lipid kinases in medulloblastoma cell lines. The analysis of cell proliferation, in the presence or absence of a low dose of cisplatin after siRNA transfection, identified new protein and lipid kinases involved in medulloblastoma chemoresistance. PLK1 (polo-like kinase 1) was identified as a kinase involved in proliferation in medulloblastoma cell lines. Moreover, a set of 6 genes comprising ATR, LYK5, MPP2, PIK3CG, PIK4CA, and WNK4 were identified as contributing to both cell proliferation and resistance to cisplatin treatment in medulloblastoma cells. An analysis of the expression of the 6 target genes in primary medulloblastoma tumor samples and cell lines revealed overexpression of LYK5 and PIK3CG. The results of the siRNA screen were validated by target inhibition with specific pharmacological inhibitors. A pharmacological inhibitor of p110γ (encoded by PIK3CG) impaired cell proliferation in medulloblastoma cell lines and sensitized the cells to cisplatin treatment. Together, our data show that the p110γ phosphoinositide 3-kinase isoform is a novel target for combinatorial therapies in medulloblastoma.  相似文献   

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Summary. We have characterized a basic peroxidase with -3,4-anhydrovinblastine (AVLB) synthase activity, which was purified from Catharanthus roseus leaves. This enzyme was the single peroxidase isoenzyme detected in C. roseus leaves, and the single AVLB synthase activity detected in C. roseus extracts. It was observed that the monomeric substrates of AVLB, vindoline and catharanthine, are both suitable electron donors for the oxidizing intermediates of the basic peroxidase, compounds I and II. Results also showed that the reaction proceeds by a radical-propagated mechanism. Substrate specificity studies of the enzyme revealed that it was also able to oxidize several common peroxidase substrates, indicating a broad range of substrate specificity that is characteristic of class III plant peroxidases. Cytochemical studies showed that the enzyme is localized in C. roseus mesophyll vacuoles, in individual spots at the inner surface of the tonoplast. This particular location suggests a meaningful spatial organization that led to the proposal of a metabolic channeling model for the peroxidase-mediated synthesis of AVLB. The importance of this type of mechanism in the regulation of peroxidase isoenzyme functions in vivo is discussed. In view of the results obtained it is concluded that the basic peroxidase present in C. roseus leaves fulfills all the requirements to be considered as an AVLB synthase, and it is proposed that this specific function of this multifunctional enzyme is determined by metabolic channeling resulting from specific protein–protein interactions.Correspondence and reprints: Institute for Molecular and Cell Biology, University of Porto, rua Campo Alegre 823, 4150-180 Porto, Portugal.Received March 15, 2002; accepted February 4, 2003; published online August 26, 2003  相似文献   

15.

Objective

Studies in children with heart disease have been hampered by a lack of easily identifiable patient groups. Currently, there are few prospective population-based registries covering the entire spectrum of heart disease in children. KinCor is a Dutch national registry for children with heart diseases. This paper presents the aims, design and interim results of the KinCor project.

Methods

All children presenting at a Dutch university medical centre with a diagnosis of heart disease from 2012 onwards were eligible for registration in the KinCor database. Data entry is through a web-based portal. Entry codes have been synchronised with the European Paediatric Cardiac Coding system, allowing coupling with similar databases for adults, such as CONCOR.

Results

Between June 2012 and July 2015, 8421 patients were registered (76?% of those eligible). Median age of the patients was 9.8 years, 44.7?% were female; 6782 patients had morphological congenital heart disease. The most prevalent morphological congenital heart defects were ventricular septal defects (18?%), Tetralogy of Fallot (10?%) and transposition of great arteries (9?%). For 42?% of the patients additional diagnoses were registered. Sixty percent of patients had undergone at least one intervention (catheter intervention or surgery).

Conclusion

The KinCor database has developed into a large registry of data of children with all types of heart disease and continues to grow. This database will provide the opportunity for epidemiological research projects on congenital and other types of heart disease in children. Entry codes are shared with the CONCOR database, which may provide a unique dataset.
  相似文献   

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In patients with osteosarcoma several causative factors are implicated in the occurrence of osteoporosis, such as no weight-bearing, pre- and post-surgical immobilization, and neoadjuvant and adjuvant chemotherapy. Nevertheless, osteoporotic fractures are a rare complication in young patients. We report the case of a spontaneous greenstick fracture of the distal tibia occurring during adjuvant chemotherapy in a 12-year-old Caucasian girl. Among the various drugs, the main role of methotrexate was investigated. A review of the literature is also presented along with a discussion about the role of preventive agents able to reduce the occurrence of osteopenia and/or osteoporosis following cancer treatment.  相似文献   

18.
It is still unclear to what extent variations in foliar δ13C and nitrogen can be used to detect seasonal changes in canopy productivity. We hypothesize that in a wet and cloudy fir forest, seasonally higher litterfall and lower leaf area index (LAI) are correlated with higher mass-based leaf nitrogen (N mass) and net primary productivity (NPP), while foliar δ13C may change with specific leaf area (SLA), area-based leaf nitrogen (N area), and/or starch concentration. In order to test our hypotheses, stand-level litterfall and the means of δ13C, N mass, N area, SLA, and starch concentration of canopy needles for a wet and cloudy Abies fabri forest in the Gongga Mountains were monthly measured during the growing season. Seasonal estimates of LAI were obtained from our previous work. A conceptual model was used to predict seasonal NPP of the fir forest. Seasonal mean δ13C and N mass and climatic variables were used as inputs. The δ13C across 1–7-year-old needles increased from May to September associated with decreasing SLA and increasing N area. There were no significant differences in seasonal starch concentration. With increasing litterfall and decreasing LAI, seasonal mean N mass increased, while the δ13C varied little. The simulated NPP increased with increasing litterfall and related traits of N mass and N area. Our data generally supported the hypotheses. The results also suggest that in the forest with relatively moist and cloudy environment, the largest fraction of annual carbon gain may occur in the early part of the growing season when higher litterfall results in higher N mass of canopy leaves.  相似文献   

19.
The Apolipoprotein A5 (APO A5) ?1131T/C, fibrinogen β (FgB) ?455G/A, ?148C/T, and cholesteryl ester transfer protein (CETP) TaqIB gene polymorphisms have been indicated to be associated with the coronary artery disease (CAD) risk, but the individual study results are still inconsistent. To explore the relationship between APO A5 ?1131T/C, FgB ?455G/A, ?148C/T, and CETP TaqIB gene polymorphisms and CAD in the Chinese population, the current meta-analysis involving 15,055 subjects from 40 individual studies was conducted. The pooled odds ratio (OR) for the association between APO A5 ?1131T/C, FgB ?455G/A, ?148C/T, and CETP TaqIB gene polymorphisms and CAD and its corresponding 95 % confidence interval (95 % CI) were evaluated by random or fixed effect model. A significant association between APO A5 ?1131T/C gene polymorphism and CAD in the Chinese population was found under an allelic (OR: 1.33, 95 % CI: 1.22–1.44, P < 0.00001), recessive (OR: 1.67, 95 % CI: 1.25–2.25, P = 0.0006), dominant (OR: 0.820, 95 % CI: 0.767–0.876, P = 1.0 × 10?10), homozygous (OR: 2.36, 95 % CI: 1.55–3.58, P < 0.0001) and heterozygous genetic models (OR: 1.136, 95 % CI:1.075–1.200, P = 1.0 × 10?10). A significant association between FgB ?455G/A gene polymorphism and CAD was also detected in the Chinese population under an allelic (OR: 1.50, 95 % CI: 1.25–1.81, P < 0.0001), dominant (OR: 0.864, 95 % CI: 0.819–0.912, P = 1.0 × 10?10), homozygous (OR: 1.616, 95 % CI: 1.213–2.152, P = 0.001) and heterozygous genetic models (OR: 1.245, 95 % CI:1.138–1.361, P = 1.0 × 10?10). No significant association was found between them under a recessive genetic model (OR: 1.124, 95 % CI: 0.844–1.497, P = 0.424). A significant association was also found between FgB ?148C/T gene polymorphism and CAD in the Chinese population under an allelic (OR: 1.34, 95 % CI: 1.06–1.71, P = 0.02), recessive (OR: 1. 65, 95 % CI: 1.02–2.69, P = 0.04), dominant (OR: 0.924, 95 % CI: 0.872–0.978, P = 0.007) and homozygous genetic models (OR: 0.968, 95 % CI: 0.942–0.995, P = 0.018). No significant association was found between them under a heterozygous genetic model (OR: 0.979, 95 % CI: 0.937–1.023, P = 0.342). In the whole Chinese population, no significant association between the CETP TaqIB gene polymorphism and CAD was found under an allelic (OR: 1.17, 95 % CI: 0.94–1.45, P = 0.15), dominant (OR: 1.46, 95 % CI: 0.80–2.67, P = 0.22) or recessive genetic models (OR: 0.68, 95 % CI: 0.32–1.44, P = 0.31). However, in the subgroup analysis stratified by ethnicity, there was a significant association between them under an allelic (OR: 1.27, 95 % CI: 1.07–1.52, P = 0.007) and dominant genetic model (OR: 2.04, 95 % CI: 1.49–2.79, P < 0.00001) in the Han subgroup. In the Chinese population, the APO A5 ?1131T/C and FgB ?455G/A, ?148C/T gene polymorphisms were implied to be associated with CAD susceptibility. The APO A5 ?1131C, FgB ?455A, and ?148T alleles might confer susceptibility to CAD. CETP TaqIB gene polymorphism was suggested to be associated with CAD susceptibility in the Chinese Han population. Carriers with B1 allele of CETP TaqIB gene might be predisposed to CAD in the Chinese Han population.  相似文献   

20.
Genetic deficiency of the glycogen-debranching enzyme (debrancher) causes glycogen storage disease type III (GSD III), which is divided into two subtypes: IIIa and IIIb. In GSD IIIb, glycogen accumulates only in the liver, whereas both liver and muscles are involved in GSD IIIa. The molecular basis for the differences between the two subtypes has not been fully elucidated. Recently, mutations in exon 3 of the debrancher gene were reported to be specifically associated with GSD IIIb. However, we describe a homozygous GSD IIIb patient without mutations in exon 3. Analysis of the patient’s debrancher cDNA revealed an 11-bp insertion in the normal sequence. An A to G transition at position –12 upstream of the 3′ splice site of intron 32 (IVS 32 A–12→G) was identified in the patient’s debrancher gene. No mutations were found in exon 3. Mutational analysis of the family showed the patient to be homozygous for this novel mutation as well as three polymorphic markers. Furthermore, the mother was heterozygous and the parents were first cousins. The acceptor splice site mutation created a new 3′ splice site and resulted in insertion of an 11-bp intron sequence between exon 32 and exon 33 in the patient’s debrancher mRNA. The predicted mutant enzyme was truncated by 112 amino acids as a result of premature termination. These findings suggested that a novel IVS 32 A–12→G mutation caused GSD IIIb in this patient. Received: 1 August 1997 / Accepted: 22 September 1997  相似文献   

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