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1.
For a long time, classification of Demodex mites has been based mainly on their hosts and phenotypic characteristics. A new subspecies of Demodex folliculorum has been proposed, but not confirmed. Here, cox1 partial sequences of nine isolates of three Demodex species from two geographical sources (China and Spain) were studied to conduct molecular identification of D. folliculorum. Sequencing showed that the mitochondrial cox1 fragments of five D. folliculorum isolates from the facial skin of Chinese individuals were 429 bp long and that their sequence identity was 97.4%. The average sequence divergence was 1.24% among the five Chinese isolates, 0.94% between the two geographical isolate groups (China (5) and Spain (1)), and 2.15% between the two facial tissue sources (facial skin (6) and eyelids (1)). The genetic distance and rate of third-position nucleotide transition/transversion were 0.0125, 2.7 (3/1) among the five Chinese isolates, 0.0094, 3.1 (3/1) between the two geographical isolate groups, and 0.0217, 4.4 (3/1) between the two facial tissue sources. Phylogenetic trees showed that D. folliculorum from the two geographical isolate groups did not form sister clades, while those from different facial tissue sources did. According to the molecular characteristics, it appears that subspecies differentiation might not have occurred and that D. folliculorum isolates from the two geographical sources are of the same population. However, population differentiation might be occurring between isolates from facial skin and eyelids.  相似文献   

2.
A total of 64 patients with β-lactam allergy and 30 control subjects were enrolled in a case-control study. This study is aimed to analyze the relationship between β-lactam allergy and 10 single nucleotide polymorphisms (SNPs) in interleukin-10 (IL-10), IL-13, IL-4Rα, high-affinity immunoglobulin E-receptor β chain (FcεRIβ), interferon γ receptor 2 (IFNGR2), and CYP3A4, and within the Han Chinese population of Northwest China. Genotyping for the SNPs was conducted using the Sequenom MassARRAY®platform. SPSS 17.0 was employed to analyze the statistical data and SHEsis was used to perform the haplotype reconstruction and analyze linkage disequilibrium of SNPs of IL-10 and IL-13. The results showed that the genotype distribution of CYP3A4 rs2242480/CT differed significantly between case and control groups of males (P=0.022; odds ratio (OR)=0.167, 95% confidence interval (CI): 0.032–0.867). Further analysis showed that CCA, CCG, and TAA haplotypes of IL-10 had no significant correlation in patients with β-lactam allergy. The correlation between CCT and CAC haplotypes of IL-13 and β-lactam allergy needs to be further studied. The analysis did not reveal any differences in the distribution of others gene polymorphisms between cases and controls.  相似文献   

3.
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4.
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5.
Mutations of fms-like tyrosine kinase 3 (FLT3) and nucleophosmin (NPM1) exon 12 genes are the most common abnormalities in adult acute myeloid leukemia (AML) with normal cytogenetics. To assess the prognostic impact of the two gene mutations in Chinese AML patients, we used multiplex polymerase chain reaction (PCR) and capillary electrophoresis to screen 76 AML patients with normal cytogenetics for mutations in FLT3 internal tandem duplication (FLT3/ITD) and exon 12 of the NPM1 gene. FLT3/ITD mutation was detected in 15 (19.7%) of 76 subjects, and NPM1 mutation in 20 (26.3%) subjects. Seven (9.2%) cases were positive for both FLT3/ITD and NPM1 mutations. Significantly more FLT3/ITD aberration was detected in subjects with French-American-British (FAB) M1 (42.8%). NPM1 mutation was frequently detected in subjects with M5 (47.1%) and infrequently in subjects with M2 (11.1%). FLT3 and NPM1 mutations were significantly associated with a higher white blood cell count in peripheral blood and a lower CD34 antigen expression, but not age, sex, or platelet count. Statistical analysis revealed that the FLT3/ITDpositive group had a lower complete remission (CR) rate (53.3% vs. 83.6%). Survival analysis showed that the FLT3/ITD-positive/NPM1 mutation-negative group had worse overall survival (OS) and relapse-free survival (RFS). The FLT3/ITD-positive/NPM1 mutation-positive group showed a trend towards favorable survival compared with the FLT3/ITD-positive/NPM1 mutation-negative group (P=0.069). Our results indicate that the FLT3/ITD mutation might be a prognostic factor for an unfavorable outcome in Chinese AML subjects with normal cytogenetics, while NPM1 mutation may be a favorable prognostic factor for OS and RFS in the presence of FLT3/ITD.  相似文献   

6.
Aphrodisiacs are required to improve male sexual function under stressful conditions. Due to the effects of oxidative stress and dopamine on male sexual function, we hypothesized that Moringa oleifera leaves might improve male sexual dysfunction induced by stress. Therefore, the effects on various factors playing important roles in male sexual behavior, such as antioxidant effects, the suppression of monoamine and phosphodiesterase type 5 (PDE-5) activities, serum testosterone and corticosterone levels, and histomorphological changes in the testes, of a hydroethanolic extract of M. oleifera leaves were investigated. Various doses of extract including 10, 50, and 250 mg/kg body weight (BW) were given orally to male Wistar rats before exposure to 12 h-immobilization stress for 7 d. The results demonstrated that the extract showed both antioxidant and monoamine oxidase type B (MAO-B) suppression activities. At 7 d of treatment, the low dose of extract improved sexual performance in stress-exposed rats by decreasing intromission latency and increasing intromission frequency. It also suppressed PDE-5 activity, decreased serum corticosterone level, but increased serum testosterone, numbers of interstitial cells of Leydig and spermatozoa. The increased numbers of interstitial cells of Leydig and spermatozoa might have been due to the antioxidant effect of the extract. The increased sexual performance during the intromission phase might have been due to the suppression of MAO-B and PDE-5 activities and increased testosterone. Therefore, M. oleifera is a potential aphrodisiac, but further research concerning the precise underlying mechanisms is still needed.  相似文献   

7.
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8.
To our knowledge, few reports on Demodex studied at the molecular level are available at present. In this study our group, for the first time, cloned, sequenced and analyzed the chitin synthase (CHS) gene fragments of Demodex folliculorum, Demodex brevis, and Demodex canis (three isolates from each species) from Xi’an China, by designing specific primers based on the only partial sequence of the CHS gene of D. canis from Japan, retrieved from GenBank. Results show that amplification was successful only in three D. canis isolates and one D. brevis isolate out of the nine Demodex isolates. The obtained fragments were sequenced to be 339 bp for D. canis and 338 bp for D. brevis. The CHS gene sequence similarities between the three Xi’an D. canis isolates and one Japanese D. canis isolate ranged from 99.7% to 100.0%, and those between four D. canis isolates and one D. brevis isolate were 99.1%–99.4%. Phylogenetic trees based on maximum parsimony (MP) and maximum likelihood (ML) methods shared the same clusters, according with the traditional classification. Two open reading frames (ORFs) were identified in each CHS gene sequenced, and their corresponding amino acid sequences were located at the catalytic domain. The relatively conserved sequences could be deduced to be a CHS class A gene, which is associated with chitin synthesis in the integument of Demodex mites.  相似文献   

9.
Utilization of a two-line breeding system via photoperiod-thermo sensitive male sterility has a great potential for hybrid production in wheat (Triticum aestivum L.). 337S is a novel wheat male sterile line sensitive to both short daylength/low temperature and long daylength/high temperature. Five F2 populations derived from the crosses between 337S and five common wheat varieties were developed for genetic analysis. All F1’s were highly fertile while segregation occurred in the F2 populations with a ratio of 3 fertile:1 sterile under short daylength/low temperature. It is shown that male sterility in 337S was controlled by a single recessive gene, temporarily designated as wptms3. Bulked segregant analysis (BSA) coupled with simple sequence repeat (SSR) markers was applied to map the sterile gene using one mapping population. The wptms3 gene was mapped to chromosome arm 1BS and flanked by Xgwm413 and Xgwm182 at a genetic distance of 3.2 and 23.5 cM, respectively. The accuracy and efficiency of marker-assisted selection were evaluated and proved essential for identifying homozygous recessive male sterile genotypes of the wptms3 gene in F2 generation.  相似文献   

10.
Objective:Weed pollens are common sources of allergens worldwide.The prevalence of weed pollen sensitization is not yet fully known in China.The purpose of this study was to investigate the prevalence of sensitization to weed allergens from Artemisia,Ambrosia,and Humulus in northern China.Methods:A total of 1144 subjects(aged from 5 to 68 years) visiting our clinic from June to October 2011 underwent intradermal testing using a panel of 25 allergen sources.Subjects with positive skin responses to any pollen were further tested for their serum concentrations of IgE antibodies against Artemisia vulgaris,Ambrosia artemisiifolia,and Humulus scandens,and against the purified allergens,Art v 1 and Amb a 1.Results:Of 1144 subjects,170 had positive intradermal reactions to pollen and 144 donated serum for IgE testing.The prevalence of positive intradermal responses to pollens of Artemisia sieversiana,Artemisia annua,A.artemisiifolia,and H.scandens was 11.0%,10.2%,3.7%,and 6.6%,respectively.Among the intradermal positive subjects,the prevalence of specific IgE antigens to A.vulgaris was 58.3%,to A.artemisiifolia 14.7%,and to H.scandens 41.0%.The prevalence of specific IgE antigens to the allergen Art v 1 was 46.9%,and to Amb a 1 was 11.2%.The correlation between the presence of IgE antibodies specific to A.vulgaris and to the Art v 1 antigen was very high.Subjects with A.artemisiifolia specific IgE also had A.vulgaris specific IgE,but with relatively high levels of A.vulgaris IgE antibodies.There were no correlations between the presence of IgE antibodies to H.scandens and A.vulgaris or to H.scandens and A.artemisiifolia.Conclusions:The intradermal prevalence of weed pollen sensitization among allergic subjects in northern China is about 13.5%.Correlations of specific IgE antibodies suggest that pollen allergens from Artemisia and Humulus are independent sources for primary sensitization.  相似文献   

11.
Biotransformation of phytosterol(PS) by a newly isolated mutant Mycobacterium neoaurum ZJUVN-08 to produce androstenedione has been investigated in this paper.The parameters of the biotransformation process were optimized using fractional factorial design and response surface methodology.Androstenedione was the sole product in the fermentation broth catalyzed by the mutant M.neoaurum ZJUVN-08 strain.Results showed that molar ratio of hydroxypropyl-β-cyclodextrin(HP-β-CD) to PS and substrate concentrations were the two most significant factors affecting androstenedione production.By analyzing the statistical model of three-dimensional surface plot,the optimal process conditions were observed at 0.1 g/L inducer,pH 7.0,molar ratio of HP-β-CD to PS 1.92:1,8.98 g/L PS,and at 120 h of incubation time.Under these conditions,the maximum androstenedione yield was 5.96 g/L and nearly the same with the non-optimized(5.99 g/L),while the maximum PS conversion rate was 94.69% which increased by 10.66% compared with the non-optimized(84.03%).The predicted optimum conditions from the mathematical model were in agreement with the verification experimental results.It is considered that response surface methodology was a powerful and efficient method to optimize the parameters of PS biotransformation process.  相似文献   

12.

Objective

A study in a Caucasian population has identified two single-nucleotide polymorphisms (SNPs) in ZNF533, one in DOCK4, and two in IMMP2L, which were all significantly associated with autism. They are located in AUTS1 and AUTS5, which have been identified as autism susceptibility loci in several genome-wide screens. The present study aimed to investigate whether ZNF533, DOCK4, and IMMP2L genes are also associated with autism in a northeastern Chinese Han population.

Methods

We performed a similar association study using families with three individuals (one autistic child and two unaffected parents). A family-based transmission disequilibrium test (TDT) was used to analyze the results.

Results

There were significant associations between autism and the two SNPs of ZNF533 gene (rs11885327: χ 2=4.5200, P=0.0335; rs1964081: χ 2=4.2610, P=0.0390) and the SNP of DOCK4 gene (rs2217262: χ 2=5.3430, P=0.0208).

Conclusions

Our data suggest that ZNF533 and DOCK4 genes are linked to a predisposition to autism in the northeastern Chinese Han population.  相似文献   

13.
The initiators caspase-9(CASP9) and caspase-10(CASP10) are two key controllers of apoptosis and play important roles in carcinogenesis.This study aims to explore the association between CASPs gene polymorphisms and colorectal cancer(CRC) susceptibility in a population-based study.A two-stage designed population-based case-control study was carried out,including a testing set with 300 cases and 296 controls and a validation set with 206 cases and 845 controls.A total of eight tag selected single nucleotide polymorphisms(SNPs) in CASP9 and CASP10 were chosen based on HapMap and the National Center of Biotechnology Information(NCBI) datasets and genotyped by restriction fragment length polymorphism(RFLP) assay.Multivariate logistic regression models were applied to evaluate the association of SNPs with CRC risk.In the first stage,from eight tag SNPs,three polymorphisms rs4646077(odds ratio(OR) AA+AG:0.654,95% confidence interval(CI):0.406-1.055;P=0.082),rs4233532(OR CC:1.667,95% CI:0.967-2.876;OR CT:1.435,95% CI:0.998-2.063;P=0.077),and rs2881930(OR CC:0.263,95% CI:0.095-0.728,P=0.036) showed possible association with CRC risk.However,none of the three SNPs,rs4646077(OR AA+AG:1.233,95% CI:0.903-1.683),rs4233532(OR CC:0.892,95% CI:0.640-1.243;OR CT:1.134,95% CI:0.897-1.433),and rs2881930(OR CC:1.096,95% CI:0.620-1.938;OR CT:1.009,95% CI:0.801-1.271),remained significant with CRC risk in the validation set,even after stratification for different tumor locations(colon or rectum).In addition,never tea drinking was associated with a significantly increased risk of CRC in testing set together with validation set(OR:1.755,95% CI:1.319-2.334).Our results found that polymorphisms of CASP9 and CASP10 genes may not contribute to CRC risk in Chinese population and thereby the large-scale case-control studies might be in consideration.In addition,tea drinking was a protective factor for CRC.  相似文献   

14.
The Rhodobacter capsulatus hemA gene, which encodes 5-aminolevulinic acid synthase (ALAS), was expressed in Escherichia coli Rosetta (DE3) and the enzymatic properties of the purified recombinant ALAS (RC-ALAS) were studied. Compared with ALASs encoded by hemA genes from Agrobacterium radiobacter (AR-ALAS) and Rhodobacter sphaeroides (RS-ALAS), the specific activity of RC-ALAS reached 198.2 U/mg, which was about 31.2% and 69.5% higher than those of AR-ALAS (151.1 U/mg) and RS-ALAS (116.9 U/mg), respectively. The optimum pH values and temperatures of the three above mentioned enzymes were all pH 7.5 and 37 °C, respectively. Moreover, RC-ALAS was more sensitive to pH, while the other two were sensitive to temperature. The effects of metals, ethylene diamine tetraacetic acid (EDTA), and sodium dodecyl sulfate (SDS) on the three ALASs were also investigated. The results indicate that they had the same effects on the activities of the three ALASs. SDS and metal ions such as Co2+, Zn2+, and Cu2+ strongly inhibited the activities of the ALASs, while Mn2+ exerted slight inhibition, and K+, Ca2+, Ba2+, Mg2+, or EDTA had no significant effect. The specificity constant of succinyl coenzyme A [(k cat/K m)S-CoA] of RC-ALAS was 1.4989, which was higher than those of AR-ALAS (0.7456) and RS-ALAS (1.1699), showing its high catalytic efficiency. The fed-batch fermentation was conducted using the recombinant strain containing the R. capsulatus hemA gene, and the yield of 5-aminolevulinic acid (ALA) achieved was 8.8 g/L (67 mmol/L) under the appropriate conditions.  相似文献   

15.
Objective: XRCC1 polymorphism is a research hotpot in individual treatment for non-small cell lung cancer (NSCLC). To obtain the association between XRCC1 polymorphism and clinical outcome of platinum-based treatment for NSCLC, a meta-analysis was conducted. Methods: Databases including PubMed, Embase, Cochrane, and Chinese National Knowledge Infrastructure (CNKI) were searched for publications that met the inclusion criteria. A fixed effect model was used to estimate pooled odds ratio (OR) and hazard ratio (HR) with 95% confidence interval (CI) for the association between XRCC1 Arg399Gln and response or survival of platinum-based treatment for advanced NSCLC. A chi-squared-based Q-test was used to test the heterogeneity hypothesis. Egger’s test was used to check publication bias. Results: Seventeen published case-control studies that focus on the association between XRCC1 Arg399Gln and response or survival of platinum-based treatment for advanced NSCLC in 2 256 subjects were included in this meta-analysis, of whom 522 were AA genotypes (23.2% frequency), 916 AG genotypes (40.6% frequency), and 818 GG genotypes (36.2% frequency). The overall response rate (ORR) was 45.2% (110/243) for AA genotype patients, 29.9% for AG genotype (73/244), and 30.7% for GG genotype (124/403). The heterogeneity test did not show any heterogeneity and the Egger’s test did not reveal an obvious publication bias among the included studies. The meta-analysis indicated that AA genotype patients presented higher response rates toward platinum drug treatment compared with G model (GG+GA) patients (GG vs. AA model: OR=0.489, 95% CI 0.266–0.900, P=0.021; AG vs. AA model: OR=0.608, 95% CI 0.392–0.941, P=0.026; GA+AA vs. GG model: OR=1.259, 95% CI 0.931–1.701, P=0.135; GG+GA vs. AA model: OR=0.455, 95% CI 0.313–0.663, P=0.0001). However, no evidence validates XRCC1 associates with the survival following platinum drug therapy. Conclusions: Our meta-analysis suggested that XRCC1 Arg399Gln is related with the sensitivity of NSCLC patients to platinum-based treatment. AA genotype patients present more desirable curative effectiveness compared with other patients.  相似文献   

16.
The metabolic activity of organisms can be measured by recording the heat output using microcalorimetry. In this paper, the total alkaloids in the traditional Chinese medicine Radix Aconiti Lateralis were extracted and applied to Escherichia coli and Staphylococcus aureus. The effect of alkaloids on bacteria growth was studied by microcalorimetry. The power-time curves were plotted with a thermal activity monitor (TAM) air isothermal microcalorimeter and parameters such as growth rate constant (μ), peak-time (Tm), inhibitory ratio (I), and enhancement ratio (E) were calculated. The relationships between the concentration of Aconitum alkaloids and μ of E. coli or S. aureus were discussed. The results showed that Aconitum alkaloids had little effect on E. coli and had a potentially inhibitory effect on the growth of S. aureus.  相似文献   

17.
Anoectochilus formosanus, commonly known as “Jewel Orchid”, is a Chinese folk medicine used to treat hypertension, diabetes, and heart disease. The existence of A. formosanus is currently threatened by habitat loss, human and animal consumption, etc. The highly potent medicinal activity of A. formosanus is due to its secondary metabolites, especially kinsenosides and flavonoids. This orchid also has a unique mycorrhizal relationship. Most adult orchids rely on endophytes for mineral nutrition and have complex interactions with them, which are related to plant growth, yield and changes in secondary metabolites. This study investigated the promoting role of F-23 fungus (genus Mycena) on the biomass and contents of kinsenosides and flavonoids of A. formosanus in pot culture. The following were observed after 10 weeks of symbiotic cultivation: increased shoot height, shoot dry weight, and leaf numbers by 16.6%, 31.3%, and 22.5%, respectively; increased contents of kinsenosides, isorhamnetin-3-O-β-d-rutinoside, and isorhamnetin-3-O-β-d-glucopyranoside by 85.5%, 226.1%, and 196.0%, respectively; some hyphae in epidermal cells dyed red and/or reddish brown by safranine; and, significantly reduced number of starch grains in cortical cells. Moreover, F-23 fungus significantly improved the kinsenoside and flavonoid contents of A. formosanus. These findings supported the reports that endophytes can alter the production of secondary metabolites in their plant hosts, although further physiological, genetic and ecological analyses are warranted.  相似文献   

18.
It is widely accepted that body weight and adipose mass are tightly regulated by homeostatic mechanisms, in which leptin plays a critical role through hypothalamic pathways, and obesity is a result of homeostatic disorder. However, in C57BL/6J mice, we found that Rcan2 increases food intake and plays an important role in the development of age- and diet-induced obesity through a leptin-independent mechanism. RCAN2 was initially identified as a thyroid hormone (T3)-responsive gene in human fibroblasts. Expression of RCAN2 is regulated by T3 through the PI3K-Akt/PKB-mTOR-Rps6kb1 signaling pathway. Intriguingly, both Rcan2?/? and Rps6kb1?/? mutations were reported to result in lean phenotypes in mice. In this study we compared the effects of these two mutations on growth and body weight in C57BL/6J mice. We observed reduced body weight and lower fat mass in both Rcan2?/? and Rps6kb1?/? mice compared to the wild-type mice, and we reported other differences unique to either the Rcan2?/? or Rps6kb1?/? mice. Firstly, loss of Rcan2 does not directly alter body length; however, Rcan2?/? mice exhibit reduced food intake. In contrast, Rps6kb1?/? mice exhibit abnormal embryonic development, which leads to smaller body size and reduced food intake in adulthood. Secondly, when fed a normal chow diet, Rcan2?/? mice weigh significantly more than Rps6kb1?/? mice, but both Rcan2?/? and Rps6kb1?/? mice develop similar amounts of epididymal fat. On a high-fat diet, Rcan2?/? mice gain body weight and fat mass at slower rates than Rps6kb1?/? mice. Finally, using the double-knockout mice (Rcan2?/?Rps6kb1?/?), we demonstrate that concurrent loss of Rcan2 and Rps6kb1 has an additive effect on body weight reduction in C57BL/6J mice. Our data suggest that Rcan2 and Rps6kb1 mutations both affect growth and body weight of mice, though likely through different mechanisms.  相似文献   

19.
Objective: Labisia pumila var. alata, commonly known as ’Kacip Fatimah’ or ’Selusuh Fatimah’ in Southeast Asia, is traditionally used by members of the Malay community because of its post-partum medicinal properties. Its various pharmaceutical applications cause an excessive harvesting and lead to serious shortage in natural habitat. Thus, this in vitro propagation study investigated the effects of different plant growth regulators (PGRs) on in vitro leaf and stem explants of L. pumila. Methods: The capabilities of callus, shoot, and root formation were evaluated by culturing both explants on Murashige and Skoog (MS) medium supplemented with various PGRs at the concentrations of 0, 1, 3, 5, and 7 mg/L. Results: Medium supplemented with 3 mg/L indole-3-butyric acid (IBA) showed the optimal callogenesis from both leaf and stem explants with (72.34±19.55)% and (70.40±14.14)% efficacy, respectively. IBA was also found to be the most efficient PGR for root induction. A total of (50.00±7.07)% and (77.78±16.47)% of root formation were obtained from the in vitro stem and leaf explants after being cultured for (26.5±5.0) and (30.0±8.5) d in the medium supplemented with 1 and 3 mg/L of IBA, respectively. Shoot formation was only observed in stem explant, with the maximum percentage of formation ((100.00±0.00)%) that was obtained in 1 mg/L zeatin after (11.0±2.8) d of culture. Conclusions: Callus, roots, and shoots can be induced from in vitro leaf and stem explants of L. pumila through the manipulation of types and concentrations of PGRs.  相似文献   

20.
Renewed interest in natural materials as food flavors and preservatives has led to the search for suitable essential oils. Moringa oleifera seed essential oil was extracted by solvent-free microwave and hydrodistillation. This study assessed its chemical constituents. Cytotoxicity of the oils was investigated using hatchability and lethality tests on brine shrimps. A total of 16 and 26 compounds were isolated from the hydrodistillation extraction (HDE) and solvent-free microwave extraction (SME) oils, respectively, which accounted for 97.515% and 97.816% of total identifiable constituents, respectively. At 24 h when the most eggs had hatched, values of the SME (56.7%) and HDE (60.0%) oils were significantly different (P<0.05) from those of sea water (63.3%) and chloramphenicol (15.0%). Larva lethality was different significantly (P<0.05) between HDE and SME oils at different concentrations and incubation periods. The median lethal concentration (LC50) of the oils was >1000 mg/ml recommended as an index for non-toxicity, which gives the oil advantage over some antioxidant, antimicrobial, therapeutic, and preservative chemicals.  相似文献   

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