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1.
Front Plant Sci ; 14: 1164451, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37457345

RESUMEN

To fully exploit the economic value of the Chinese endemic species Pteroceltis tatarinowii and provide new resources for forage production, the forage nutritional value of P. tatarinowii leaves from different populations was analyzed and evaluated. The results were as follows: 1) There were significant differences in the forage nutrient indices of leaves from different populations. The crude protein content was 10.77%-18.65%, with an average of 14.58%, and the SDJN population had the highest crude protein content. The average crude fat, crude fiber content was 7.62%; the average neutral detergent fiber content was 25.33%; and the average acid detergent fiber contents were 6.79%, 7.62%, 25.33%, and 17.52%, respectively. The average phosphorus and calcium content in the leaves was 0.785 g·kg-1 and 58.01 g·kg-1, respectively. The tannin content was much lower than the antifeedant standard, at an average of 4.97 g·kg-1. The average total amounts of hydrolyzed and free amino acids in the leaves were 108.20 mg·g-1 and 47.87 mg·g-1, respectively. Thus, P. tatarinowii leaves have high crude protein, crude fat, and calcium contents, and low fiber, tannin contents, and are protein-rich. These results provide evidence that this species can be developed into an excellent woody forage tree. 2) There were significant differences in the forage quality evaluation indices among the populations. The forage indices of NDP, ADP, DMI, DDM, and RFV of 21 populations all met the super standard of the American Grass and Grassland Association (AFGC) for hay, two crude protein indices met the grade 1 standard, and 12 crude protein indices met the grade 2 standard. Four high-protein and high-RFV forage populations (SDJN, SDZZ, SXLQ, and AHXX) were selected. 3) The results of the correlation analysis showed that there was no significant correlation between the forage characteristics of P. tatarinowii leaves and latitude and longitude, indicating no significant geographical variation. However, the forage characteristics were strongly correlated with elevation, average annual temperature, and annual precipitation. Thus, high elevation, low temperatures, and rainy weather can improve the forage value of the leaves. P. tatarinowii can be planted to provide leaf forage in cold and wet areas at a specific elevation. Moreover, the forage value of P. tatarinowii leaves can be further improved by increasing nitrogen fertilizer and reducing K and Ca fertilizers during cultivation. 4) Cluster analysis revealed obvious regionalism. Taking the Yangtze River Basin as the limit, cluster analysis divided the species into four population groups: the Yangtze River Basin and northern, southwestern, and eastern coastal populations.

2.
Int J Mol Sci ; 23(9)2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35563341

RESUMEN

In nature, many different factors cause plants to develop variegated leaves. To explore the mechanism of variegated leaf formation in Pteroceltis tatarinowii, a mutant variety ('Jinyuyuan'), which was induced by ethylmethylsulfone, was selected, and its morphological structure, physiology, biochemistry, transcription and metabolism were analysed. According to differences in colour values, the colours were divided into two regions: a green region and a yellow-green region. The chlorophyll content of the two regions was significantly different. Moreover, the yellow-green regions of the leaves were significantly thinner than the green regions. The chloroplast ultrastructure in the yellow-green region revealed small chloroplasts, large vacuoles, small starch grains, obviously increased numbers of osmophilic grains, loose lamellae of the inner capsule and thin lamellae. Moreover, the yellow-green region was accompanied by oxidative stress, and the activity of the oxidative phosphorylation pathway related to oxidative activity in the transcriptome showed an upward trend. Vitamin B6 and proline contents also increased, indicating that the antioxidant activity of cells in the yellow-green region increased. Transcriptomic and metabolomic analysis showed that the differentially expressed genes (DEGs) related to chlorophyll synthesis and metabolism led to a decrease in the photosynthesis and then a decrease in the assimilation ability and contents of sucrose, starch and other assimilates. Amino acid synthesis and metabolism, lipid synthesis and the activity of metabolic pathways were obviously downregulated, and the contents of differentially accumulated metabolites associated with amino acids and lipids were also reduced. At the same time, 31 out of 32 DEGs involved in the flavonoid synthesis pathway were downregulated, which affected leaf colour. We hypothesized that the variegated leaves of P. tatarinowii 'Jinyuyuan' are caused by transcriptional and post-transcriptional regulation. Mutations in pigment and flavonoid synthesis pathway genes and transcription factor genes directly affect both pigment and flavonoid synthesis and degradation rate, which in turn affect carbon assimilation, carbon fixation, related protein synthesis and enzyme activity, lipid synthesis and degradation and the activity of other metabolic pathways, eventually leading to the formation of different colour regions.


Asunto(s)
Transcriptoma , Árboles , Clorofila/metabolismo , Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Metaboloma , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Almidón/metabolismo , Árboles/genética
3.
PLoS One ; 11(1): e0147740, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26824702

RESUMEN

Escherichia coli (E. coli) is one of the most frequent and lethal causes of bloodstream infections (BSIs). We carried out a retrospective multicenter study on antimicrobial resistance and phylogenetic background of clinical E. coli isolates recovered from bloodstream in three hospitals in Shanghai. E. coli isolates causing BSIs were consecutively collected between Sept 2013 and Sept 2014. Ninety isolates randomly selected (30 from each hospital) were enrolled in the study. Antimicrobial susceptibility testing was performed by disk diffusion. PCR was used to detect antimicrobial resistance genes coding for ß-lactamases (TEM, CTX-M, OXA, etc.), carbapenemases (IMP, VIM, KPC, NDM-1 and OXA-48), and phylogenetic groups. eBURST was applied for analysis of multi-locus sequence typing (MLST). The resistance rates for penicillins, second-generation cephalosporins, fluoroquinolone and tetracyclines were high (>60%). Sixty-one of the 90 (67.8%) strains enrolled produced ESBLs and no carbapenemases were found. Molecular analysis showed that CTX-M-15 (25/61), CTX-M-14 (18/61) and CTX-M-55 (9/61) were the most common ESBLs. Phylogenetic group B2 predominated (43.3%) and exhibited the highest rates of ESBLs production. ST131 (20/90) was the most common sequence type and almost assigned to phylogenetic group B2 (19/20). The following sequence types were ST405 (8/90) and ST69 (5/90). Among 61 ESBL-producers isolates, B2 (26, 42.6%) and ST131 (18, 29.5%) were also the most common phylogenetic group and sequence type. Genetic diversity showed no evidence suggesting a spread of these antimicrobial resistant isolates in the three hospitals. In order to provide more comprehensive and reliable epidemiological information for preventing further dissemination, well-designed and continuous surveillance with more hospitals participating was important.


Asunto(s)
Antibacterianos/farmacología , Bacteriemia/epidemiología , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Escherichia coli/epidemiología , Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Niño , Preescolar , China/epidemiología , Pruebas Antimicrobianas de Difusión por Disco , Escherichia coli/clasificación , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Femenino , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Filogenia , Reacción en Cadena de la Polimerasa , Estudios Retrospectivos , beta-Lactamasas/genética , beta-Lactamasas/metabolismo
4.
Nature ; 528(7580): 108-10, 2015 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-26605521

RESUMEN

The formation of relativistic jets by an accreting compact object is one of the fundamental mysteries of astrophysics. Although the theory is poorly understood, observations of relativistic jets from systems known as microquasars (compact binary stars) have led to a well established phenomenology. Relativistic jets are not expected to be produced by sources with soft or supersoft X-ray spectra, although two such systems are known to produce relatively low-velocity bipolar outflows. Here we report the optical spectra of an ultraluminous supersoft X-ray source (ULS) in the nearby galaxy M81 (M81 ULS-1; refs 9, 10). Unexpectedly, the spectra show blueshifted, broad Hα emission lines, characteristic of baryonic jets with relativistic speeds. These time-variable emission lines have projected velocities of about 17 per cent of the speed of light, and seem to be similar to those from the prototype microquasar SS 433 (refs 11, 12). Such relativistic jets are not expected to be launched from white dwarfs, and an origin from a black hole or a neutron star is hard to reconcile with the persistence of M81 ULS-1's soft X-rays. Thus the unexpected presence of relativistic jets in a ULS challenges canonical theories of jet formation, but might be explained by a long-speculated, supercritically accreting black hole with optically thick outflows.

5.
Ying Yong Sheng Tai Xue Bao ; 26(2): 425-9, 2015 Feb.
Artículo en Chino | MEDLINE | ID: mdl-26094456

RESUMEN

In order to explore regulatory function of H2O2 in bud dormancy release, main effects of three dormancy-breaking treatments (high temperature, hydrogen cyanamide and TDZ) on H2O2 metabolism were determined, and impacts of H2O2 on Ca2+ transport were tested using non-invasive micro-test technique. The results showed that both high temperature and hydrogen cyanamide induced H2O2 accumulation and CAT inhibition were efficient in breaking dormancy during deep dormancy period. However, TDZ showed little impacts on H2O2 metabolism and was much less effective in breaking dormancy. Dormant floral primordium was absorbing state to exogenous Ca2+ due to active calcium channels. The Ca2+ transport could be changed by exogenous H2O2. H2O2 of low concentration reduced the absorption rate of Ca2+, and at high concentration, it changed the Ca2+ transport direction from absorption to release. The results indicated that H2O2 signals were related with Ca2+ signals in dormant buds. Ca2+ signal regulated by H2O2 accumulation might be important in the dormancy-breaking signal transduction process induced by high temperature and hydrogen cyanamide.


Asunto(s)
Señalización del Calcio , Cianamida/química , Flores/fisiología , Peróxido de Hidrógeno/metabolismo , Latencia en las Plantas/fisiología , Prunus persica/fisiología , Frutas , Calor
6.
BMC Infect Dis ; 14: 260, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24886028

RESUMEN

BACKGROUND: Shigellae have become increasingly resistant to the extended-spectrum cephalosporin (ESC) worldwide and pose a great challenge to anti-infection treatment options. The purpose of this study was to determine the resistance, cephalosporin resistance mechanisms, virulence characteristic and genotype of ESC-resistant Shigella. METHODS: From 2008 to 2012, Shigella isolates collected from diarrhea patients were detected for antibiotics sensitivity by disk diffusion, cephalosporin resistance determinants and virulence genes using polymerase chain reaction (PCR) and genotyping through enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR). RESULTS: A total of 356 Shigella isolates were gathered, and 198 (55.6%, 58 S. flexneri and 140 S. sonnei) were resistant to ESC. All ESC-resistant isolates were susceptible to imipenem, and only 0.5% isolate was resistant to piperacillin/tazobactam. ESC-resistant S. flexneri showed high degrees of resistance to ampicillin (100%), ampicillin/sulbactam (96.6%), piperacillin (100%), trimethoprim/sulfamethoxazole (74.1%), ciprofloxacin (74.1%), levofloxacin (53.4%), ceftazidime (58.6%) and cefepime (58.6%). ESC-resistant S. sonnei exhibited high resistance rates to ampicillin (100%), piperacillin (100%) and trimethoprim/sulfamethoxazole (96.4%). Cephalosporin resistance genes were confirmed in 184 ESC-resistant isolates. bla(CTX-M) types (91.8%, mainly bla(CTX-M-14), bla(CTX-M-15) and bla(CTX-M-57)) were most prevalent, followed by bla(OXA-30) (26.3%). Over 99.0% ESC-resistant isolates harbored virulence genes ial, ipaH, virA and sen. However, set1 were more prevalent in ESC-resistant S. flexneri isolates than in S. sonnei isolates. ERIC-PCR results showed that 2 and 3 main genotypes were detected in ESC-resistant S. flexneri and S. sonnei, respectively. CONCLUSION: Our findings indicated that a high prevalence of ESC-resistant Shigella mediated mainly by bla(CTX-M) with stronger resistance and virulence, and the existence of specific clones responsible for these Shigella infection in the region studied.


Asunto(s)
Resistencia a las Cefalosporinas/genética , Disentería Bacilar/microbiología , Shigella/genética , Adolescente , Adulto , Antibacterianos , Cefepima , Cefalosporinas , Niño , Preescolar , China , Ciprofloxacina , Femenino , Galanina/análogos & derivados , Genes Bacterianos , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Ácido Penicilánico/análogos & derivados , Piperacilina , Combinación Piperacilina y Tazobactam , Reacción en Cadena de la Polimerasa , Shigella/patogenicidad , Sustancia P/análogos & derivados , Virulencia , beta-Lactamasas/genética
7.
PLoS One ; 8(9): e72811, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24039803

RESUMEN

OBJECTIVES: Staphylococcus aureus or methicillin-resistant Staphylococcus aureus (MRSA) has been an important pathogen causing bloodstream infections. Our study aimed to investigate the epidemiological and genetic diversity of clinical S. aureus isolates from patients with bloodstream infection in four hospitals of Shanghai from 2009 to 2011. METHODS: A collection of S. aureus isolates causing bloodstream infection from four hospitals in the central part of Shanghai was carried out. Antimicrobial susceptibility testings of collected isolates were performed according to the Clinical and Laboratory Standards Institute (CLSI) guidelines, and spa-type, multi-locus sequence typing, agr type and toxin gene profiling were performed to explore the molecular diversity. Moreover, MRSA strains were also characterized by Staphylococcal cassette chromosome mec (SCCmec) typing. RESULTS: The drugs such as linezolid, teicoplanin and vancomycin were efficacious for treating S. aureus including MRSA bloodstream infection. Methicillin-sensitive Staphylococcus aureus (MSSA) strains displayed distinct diversity in molecular characterization and toxin genes, and three virulent MSSA strains encoding at least five toxins were detected. Five community-associated MRSA (CA-MRSA) strains were found, but the majority (88.7%) of MRSA strains belonged to two epidemic clones (ST239-MRSA- III and ST5-MRSA- II) with different toxin gene profiles among patients with bloodstream infection. CONCLUSIONS: Healthcare-associated MRSA (HA-MRSA) strains were still the main pathogen causing bloodstream infections in spite of the emergence of CA-MRSA strains in hospital setting.


Asunto(s)
Bacteriemia/epidemiología , Variación Genética , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/genética , Alelos , Toxinas Bacterianas/genética , China/epidemiología , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Staphylococcus aureus/clasificación , Staphylococcus aureus/efectos de los fármacos
8.
PLoS One ; 8(4): e61219, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23596519

RESUMEN

The breakdown of self-incompatibility, which could result from the accumulation of non-functional S-haplotypes or competitive interaction between two different functional S-haplotypes, has been studied extensively at the molecular level in tetraploid Rosaceae species. In this study, two tetraploid Chinese cherry (Prunus pseudocerasus) cultivars and one diploid sweet cherry (Prunus avium) cultivar were used to investigate the ploidy of pollen grains and inheritance of pollen-S alleles. Genetic analysis of the S-genotypes of two intercross-pollinated progenies showed that the pollen grains derived from Chinese cherry cultivars were hetero-diploid, and that the two S-haplotypes were made up of every combination of two of the four possible S-haplotypes. Moreover, the distributions of single S-haplotypes expressed in self- and intercross-pollinated progenies were in disequilibrium. The number of individuals of the two different S-haplotypes was unequal in two self-pollinated and two intercross-pollinated progenies. Notably, the number of individuals containing two different S-haplotypes (S1- and S5-, S5- and S8-, S1- and S4-haplotype) was larger than that of other individuals in the two self-pollinated progenies, indicating that some of these hetero-diploid pollen grains may have the capability to inactivate stylar S-RNase inside the pollen tube and grow better into the ovaries.


Asunto(s)
Diploidia , Haplotipos , Polen/genética , Prunus/genética , Tetraploidía , Alelos , Secuencia de Aminoácidos , Clonación Molecular , Cruzamientos Genéticos , Regulación de la Expresión Génica de las Plantas , Datos de Secuencia Molecular , Especificidad de Órganos/genética , Mapeo Físico de Cromosoma , Proteínas de Plantas/química , Proteínas de Plantas/genética , Ribonucleasas/química , Ribonucleasas/genética , Alineación de Secuencia
9.
Antimicrob Agents Chemother ; 55(6): 2937-41, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21422214

RESUMEN

The study shows for the first time the presence of the Klebsiella oxytoca strain fp10 coproducing plasmid-mediated KPC-2 and IMP-8 carbapenemases. The strain was obtained from the fecal sample of an inpatient and showed high-level resistance to imipenem and ertapenem (MICs > 32 µg/ml). Conjugation experiments demonstrated the transferability of the carbapenem-resistant determinants. The results of plasmid analysis and Southern hybridization revealed that the bla(KPC-2) gene was located on transferable plasmid pFP10-1 (∼54 kb), whereas the bla(IMP-8) gene was on transferable plasmid pFP10-2 (∼180 kb). Analysis of the genetic environment of these two genes has demonstrated that ISKpn6 and ISKpn8 are involved in the spread of the bla(KPC-2) gene, while the transposable elements IS26, intI1, and tniC might contribute to the dissemination of the bla(IMP-8) gene. The chimera of several transposon-associated elements indicated a novel genetic environment of IMP-type metallo-ß-lactamase gene in Enterobacteriaceae from China.


Asunto(s)
Klebsiella oxytoca/enzimología , beta-Lactamasas/biosíntesis , Conjugación Genética , Klebsiella oxytoca/efectos de los fármacos , Klebsiella oxytoca/genética , Pruebas de Sensibilidad Microbiana , Plásmidos , Análisis de Secuencia de ADN , beta-Lactamasas/genética
10.
Scand J Infect Dis ; 43(3): 170-4, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21128708

RESUMEN

BACKGROUND: The community could be a reservoir of antibiotic resistance genes. The aim of this study was to investigate the prevalence and genetic environments of bla(CTX-M) among faecal Escherichia coli obtained from healthy persons in a region of China. METHODS: Bacteria in stool specimens were screened for extended-spectrum ß-lactamase (ESBL) production on 2 MacConkey agars, one with cefotaxime and one with ceftazidime. bla(CTX-M) and their genetic environments, as well as phylogenetic analysis and detection of the O25b-ST131 clone of E. coli, were characterized by polymerase chain reaction and sequencing. Pulsed field gel electrophoresis and conjugation assays were performed by standard procedures. RESULTS: A surprisingly high number (50.5%, 55/109) of faecal samples showed the presence of ESBL-producing E. coli. bla(CTX-M) genes were detected in all of these strains. The CTX-M-9 group (41/55, 74.5%) was found most frequently, followed by the CTX-M-1 group (16/55, 29.1%). CTX-M-14 (n = 39) was the predominant CTX-M enzyme in this study. However, the genes for the CTX-M-2 and CTX-M-8 groups were not observed. ISEcp1 was detected in 90.9% of the strains, while IS26 was observed upstream from bla(CTX-M) in only 1 strain. Phylogenetic groups A and D were found to predominate in commensal E. coli. High clonal diversity was observed and most bla(CTX-M) genes were transferable. The O25b-ST131 clone was found in 4 strains. CONCLUSIONS: This study reveals the wide dissemination of CTX-M ESBL-producing E. coli in the gut flora of healthy individuals in China.


Asunto(s)
Escherichia coli/enzimología , Escherichia coli/aislamiento & purificación , Heces/microbiología , beta-Lactamasas/biosíntesis , Adolescente , Adulto , Anciano , China , ADN Bacteriano/química , ADN Bacteriano/genética , Escherichia coli/genética , Femenino , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana/métodos , Persona de Mediana Edad , Filogenia , Reacción en Cadena de la Polimerasa , Prevalencia , Análisis de Secuencia de ADN , Adulto Joven
11.
Ying Yong Sheng Tai Xue Bao ; 21(10): 2529-35, 2010 Oct.
Artículo en Chino | MEDLINE | ID: mdl-21328939

RESUMEN

Taking the test tube 'Duke' highbush blueberry (Vaccinium corymbosum) seedlings having been transplanted to the field for 6 months as test materials, this paper studied the effects of exogenous nitric oxide (NO) on their growth, PS II photochemical activity, and antioxidant system under high temperature stress. Applying 0.2, 0.5, and 1.0 mmol x L(-1) of exogenous sodium nitroprusside (SNP) could alleviate the decrease of maximum photochemical efficiency (Fv/Fm), actual photochemical efficiency under light (phi PS II), photochemical quench (q(P)), and nonphotochemical quench (NPQ) caused by high temperature, and prevented the damage of high temperature on photosynthetic apparatus. Comparing with the control, treatments NO decreased the leaf membrane permeability and MDA content, increased the SOD and CAT activities significantly, and promoted proline accumulation. Appropriate concentration SNP could significantly alleviate the damage of high temperature stress on highbush blueberry seedlings, and 0.5 mmol x L(-1) of SNP had the most satisfactory effect.


Asunto(s)
Antioxidantes/metabolismo , Arándanos Azules (Planta)/metabolismo , Calor , Óxido Nítrico/farmacología , Complejo de Proteína del Fotosistema II/metabolismo , Arándanos Azules (Planta)/enzimología , Arándanos Azules (Planta)/crecimiento & desarrollo , Catalasa/metabolismo , Estrés Fisiológico , Superóxido Dismutasa/metabolismo
12.
Int J Antimicrob Agents ; 35(2): 114-8, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19939636

RESUMEN

A total of 803 clinical meticillin-resistant Staphylococcus aureus (MRSA) isolates obtained from Shanghai and Wenzhou in China were subjected to a screening test by disk diffusion for detection of mupirocin resistance. Among the 803 strains, 53 (6.6%) were mupirocin-resistant. Of these 53 strains, all were discovered by the agar dilution method and polymerase chain reaction (PCR) to be high-level mupirocin-resistant and to harbour the mupA gene. Plasmid DNA hybridisation and curing experiments disclosed that mupA was located on a large plasmid varying in size between 23.0kb and 52.4kb in all strains. Susceptibility testing of 10 antibiotics revealed that resistance rates between the Shanghai isolates and the Wenzhou isolates to trimethoprim/sulfamethoxazole and rifampicin differed significantly. Molecular typing by pulsed-field gel electrophoresis (PFGE), staphylococcal chromosomal cassette mec (SCCmec) and staphylococcal protein A (spa) revealed that PFGE A-SCCmec IIIA-spa t030 and PFGE B-SCCmec IIIA-spa t030 represented all of the Wenzhou strains, whereas PFGE N-SCCmec I-spa t318, PFGE P-SCCmec III-spa t037, PFGE I-SCCmec III-spa t037 and PFGE M-SCCmec IIIA-spa t002 were the predominant profiles among Shanghai isolates. These findings indicated that high-level mupirocin resistance mediated by plasmids prevailed in the clinical mupirocin-resistant MRSA from Shanghai and Wenzhou and was mainly related to the transmission of clones.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Mupirocina/farmacología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Proteínas Bacterianas/genética , Técnicas de Tipificación Bacteriana , China/epidemiología , Análisis por Conglomerados , Dermatoglifia del ADN , ADN Bacteriano/genética , Genotipo , Humanos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Proteínas Nucleares/genética , Plásmidos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
13.
Sheng Wu Gong Cheng Xue Bao ; 23(4): 628-33, 2007 Jul.
Artículo en Chino | MEDLINE | ID: mdl-17822034

RESUMEN

The genetic diversity of 279 indivdiuals from 10 populations in Shandong Province was investigated using inter-simple sequence repeat (ISSR) markers. As a result, 116 bands were amplified by 10 informative and reliable primers, of which 101 were polymorphic loci. A relatively high level of genetic diversity was revealed: PPL = 87.07, He = 0.2697, H0 = 0.3999 (at the species level); PPL = 64.58, He = 0.2004, H0 = 0.3010 (at the population level). A higher level of genetic differentiation was detected among populations with Nei's G(ST) analysis and the analysis of molecular variance (AMOVA; G(ST) = 0.2414, F(ST) = 0.2224). Habitat fragmentation and gene flow may result in genetic differentiation. UPGMA cluster analysis indicated that the four populations from Linshu, Junan, Tancheng and Feixian grouped together, whereas Laiyang populations clustered in an isolated clade. The results showed that a mixed mating system was possibly the main factor influencing the genetic structure of this species. These results, combined with other information about Castanea mollissima, may provide a valuable basis for proposing conservation strategies.


Asunto(s)
Fagaceae/genética , Variación Genética , Genética de Población , China , Marcadores Genéticos/genética , Repeticiones de Microsatélite
14.
Zhonghua Yu Fang Yi Xue Za Zhi ; 40(4): 248-52, 2006 Jul.
Artículo en Chino | MEDLINE | ID: mdl-17097003

RESUMEN

OBJECTIVE: To discuss the optimal immunization dose by observing the immunoprotective effects of different doses of recombinant Schistosoma japonicum (Chinese strain) signaling protein 14-3-3 (rSj14-3-3). METHODS: Sj14-3-3 gene was amplified by reverse transcriptase PCR (RT-PCR), subcloned into prokaryotic expression vector pET28a, then transformed into E.coli to express by inducing. Purified rSj14-3-3 was prepared through SDS polyacrylamide gel electrophoresis (SDS-PAGE), electroelution, dialysis, then BALB/c mice were divided into 5 groups and immunized in rSj14-3-3 protein followed by challenging infection (the 1st, 2nd, and 3rd groups were immunized in 50 microg, 100 microg and 300 microg antigen, respectively. The 4th, 5th groups were immunized in Freund's adjuvant and normal saline controls). After 6 weeks of challenging infection, the mice were killed and the worm and egg reduction rates were calculated. And the mice sera in different time were taken to examine the specific anti-Sj14-3-3 IgG. RESULTS: rSj14-3-3 protein was expressed successfully. After immunizing and challenging, worm reduction was found to be 28.20% in the 1st group, 43.10% in the 2nd group, 40.00% in the 3rd group, respectively. Number of eggs in liver tissue was reduced by 41.80%, 57.50%, 55.70%, respectively. Compared the results of the tested groups to the controls, the differences were of significance by t-test (worm reduction rate: t = 6.8 in the 1st group, t = 8.7 in the 2nd group, t = 7.3 in the 3rd group, P < 0.01 in all tested groups. Egg reduction rate at the group's number above: t = 11.23, t = 11.54, t = 7.99, P < 0.01 in all tested groups). As compared the results between the tested groups by chi(2), the differences were of significance between the 1st and the 2nd groups (worm reduction rate: chi(2) = 8.96, P < 0.05; egg reduction rate: chi(2) = 15.69, P < 0.05), between the 1st and the 3rd groups, the differences were also of significance (worm reduction rate: chi(2) = 6.52, P < 0.05; egg reduction rate: chi(2) = 12.52, P < 0.05). The difference was not of significance between the 2nd and the 3rd groups (worm reduction rate: chi(2) = 1.20, P > 0.05; egg reduction rate: chi(2) = 0.93, P > 0.05). In all tested groups, total anti-Sj14-3-3 specific IgG rose markedly. IgG(1) and IgG(2a) subtypes were high, but IgG(2b) and IgG(3) were near the background in four subtypes tested. CONCLUSION: Immunoprotection of rSj14-3-3 should have some relations with immunization dose, and the protection obtained from immunizing mice by using 100 microg antigen was the best.


Asunto(s)
Proteínas 14-3-3/inmunología , Antígenos Helmínticos/sangre , Proteínas del Helminto/inmunología , Schistosoma japonicum/inmunología , Proteínas 14-3-3/administración & dosificación , Animales , Anticuerpos Antihelmínticos/inmunología , Formación de Anticuerpos , Femenino , Inmunoglobulina G/sangre , Ratones , Ratones Endogámicos BALB C , Proteínas Recombinantes , Schistosoma japonicum/genética , Transducción de Señal , Vacunación
15.
Artículo en Chino | MEDLINE | ID: mdl-15108508

RESUMEN

OBJECTIVE: To evaluate the immunoprotective effect of Schistosoma japonicum (Chinese strain) recombinant signaling protein 14-3-3 (rSj14-3-3), and to observe the synergism of rSj14-3-3 and rSjGST proteins as candidate vaccine and the effect of gamma delta-T cells activated by Mtb against Schistosoma japonicum. METHODS: BALB/c mice immunized with rSj14-3-3 and rSjGST purified through SDS-PAGE, electroelution and dialysis were challenged by cercaria infection. Six weeks after challenging infection, the mice were killed and the worm and egg reduction rates were calculated. RESULTS: Worm reduction rate was found to be 32.20% in rSj14-3-3 + Freund adjuvant group, 31.10% in rSj14-3-3 + rSjGST + Freund adjuvant group, 27.96% in rSj14-3-3 + Mtb group, 26.00% in rSj14-3-3 + rSjGST + Mtb group, and 27.10% in rSjGST + Mtb group, respectively, number of eggs in liver tissue was reduced by 50.40%, 53.30%, 51.10%, 58.60% and 51.30%, respectively. CONCLUSION: rSj14-3-3 could induce partial immunity against Schistosoma japonicum in BALB/c mice, and might serve as a candidate vaccine; gamma delta-T cell activated by Mtb played a role in anti-Schistosoma japonicum similar to the immune reactions induced by Freund adjuvant, but no synergistic effect combined with rSjGST was observed.


Asunto(s)
Proteínas del Helminto/inmunología , Schistosoma japonicum/inmunología , Esquistosomiasis Japónica/prevención & control , Tirosina 3-Monooxigenasa/inmunología , Vacunas Sintéticas/inmunología , Proteínas 14-3-3 , Animales , Femenino , Glutatión Transferasa/inmunología , Ratones , Ratones Endogámicos BALB C , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Proteínas Recombinantes de Fusión/inmunología , Esquistosomiasis Japónica/inmunología , Subgrupos de Linfocitos T/inmunología
16.
Artículo en Chino | MEDLINE | ID: mdl-15108541

RESUMEN

OBJECTIVE: To study the localization of the signaling protein 14-3-3 of Schistosoma japonicum (Sj14-3-3) in the parasite. METHODS: Cercariae were collected from the infected Oncomelania hupensis for the infection of rabbits. Fifteen-day-old schistosomula and adult worms obtained from infected rabbits 15 and 42 days post-infection were used for frozen sections and indirect immunofluorescence staining with monoclonal antibody to rSj14-3-3. RESULTS: The results showed that the Sj14-3-3 distributed mainly in the tegument, subtegument, muscle, and parenchyma of both adult worms and 15-day-old schistosomula. CONCLUSION: The wide distribution and large sites of Sj14-3-3 in the parasite were clearly demonstrated, which established a significant clue for further studies of biologic actions and application of 14-3-3 protein.


Asunto(s)
Schistosoma japonicum/metabolismo , Tirosina 3-Monooxigenasa/metabolismo , Proteínas 14-3-3 , Animales , Anticuerpos Monoclonales/inmunología , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Ratones , Ratones Endogámicos BALB C , Conejos , Caracoles , Tirosina 3-Monooxigenasa/inmunología
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