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2.
Nat Commun ; 14(1): 1827, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-37005419

RESUMEN

Several groups of bacteria have complex life cycles involving cellular differentiation and multicellular structures. For example, actinobacteria of the genus Streptomyces form multicellular vegetative hyphae, aerial hyphae, and spores. However, similar life cycles have not yet been described for archaea. Here, we show that several haloarchaea of the family Halobacteriaceae display a life cycle resembling that of Streptomyces bacteria. Strain YIM 93972 (isolated from a salt marsh) undergoes cellular differentiation into mycelia and spores. Other closely related strains are also able to form mycelia, and comparative genomic analyses point to gene signatures (apparent gain or loss of certain genes) that are shared by members of this clade within the Halobacteriaceae. Genomic, transcriptomic and proteomic analyses of non-differentiating mutants suggest that a Cdc48-family ATPase might be involved in cellular differentiation in strain YIM 93972. Additionally, a gene encoding a putative oligopeptide transporter from YIM 93972 can restore the ability to form hyphae in a Streptomyces coelicolor mutant that carries a deletion in a homologous gene cluster (bldKA-bldKE), suggesting functional equivalence. We propose strain YIM 93972 as representative of a new species in a new genus within the family Halobacteriaceae, for which the name Actinoarchaeum halophilum gen. nov., sp. nov. is herewith proposed. Our demonstration of a complex life cycle in a group of haloarchaea adds a new dimension to our understanding of the biological diversity and environmental adaptation of archaea.


Asunto(s)
Halobacteriaceae , Streptomyces , Hifa/genética , Proteómica , Filogenia , ARN Ribosómico 16S/genética , Streptomyces/genética , Halobacteriaceae/genética , Esporas , Diferenciación Celular , Análisis de Secuencia de ADN , China
3.
Huan Jing Ke Xue ; 43(9): 4662-4673, 2022 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-36096607

RESUMEN

MiSeq sequencing technology was used to investigate the bacterial compositions and diversities of active patch, non-active patch, recovered patch, and healthy alpine meadows so as to understand the changes in soil bacterial community diversity during altitude change and alpine meadow degradation. The relationship between bacterial diversity and environmental factors was analyzed using redundancy analysis (RDA). The results showed that the dominant bacterial phyla in the soil included Proteobacteria, Actinobacteriota, and Acidobacteriota in the study areas. The dominant bacterial genera that were identified via the MiSeq were RB41, Sphingomonas, and Bradyrhizobium. The relative abundance of these genera decreased with altitude increase and increased with the restoration progress of degraded patches but was significantly lower than that in the alpine meadow (P<0.05). The abundance of functional bacteria related to carbon fixation in degraded patches was higher than that in the healthy alpine meadow. The bacterial Chao1 index and species number in different types of degraded patches were significantly higher than those in the alpine meadow (P<0.05). The results of the RDA suggest that biological soil crust coverage and total nitrogen were the main influencing factors on dominant bacterial phyla at the altitude of 4013 m. Biomass, total nitrogen, and pH had a great influence on the dominant bacterial phyla at the altitude of 4224 m. Biomass and total potassium significantly affected the distribution of bacterial genera at the altitude of 4013 m. Sedge coverage and available nitrogen were the main influencing factors on bacterial dominant genera at the altitude of 4224 m. Biological soil crusts and pH had a great influence on bacterial diversities. The bacterial influence factors varied greatly at different altitude areas. Therefore, we should not only pay attention to the effect of alpine meadow degradation but also consider the effect of altitude in the study of bacterial diversity changes.


Asunto(s)
Pradera , Suelo , Bacterias/genética , Nitrógeno/análisis , Ríos , Suelo/química , Microbiología del Suelo
4.
Antonie Van Leeuwenhoek ; 113(12): 2155-2165, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33151459

RESUMEN

A novel Gram-stain-positive, aerobic, cocci-shaped actinobacterium, designated YIM 75000T, was isolated from a soil sample collected from a dry-hot river valley in Yunnan Province, P.R. China. Growth was observed at 10-45 °C (optimal 37 °C), 0-8% (w/v) NaCl (optimal at 0-3% NaCl) and pH 6.0-8.0 (optimal at pH 7.3). The peptidoglycan contained LL-diaminopimelic acid, glycine, glutamic acid as well as alanine and its type was A3γ with an LL-Dpm-Gly interpeptide bridge. The major cellular fatty acids (> 10%) were C16:0, Summed In Feature 3 (C16:1 ω6c/C16:1 ω7c) and C17:1 ω8c. The predominant menaquinone was MK-9(H4). The major whole-cell sugars contained rhamnose, ribose, arabinose and mannose. The DNA G+C content was 77.0 mol%. The 16S rRNA gene sequence similarities of strain YIM 75000T with other species were less than 94%. Phylogenetic analyses based on 16S rRNA gene sequences and genome data, revealed that strain YIM 75000T together with the genus Motilibacter formed a distinct phylogenetic lineage within the phylum Actinobacteria, separating them from members of all orders. Strain YIM 75000T showed 73.4-73.7% average nucleotide identity and 19.5-19.7% digital DNA-DNA hybridization identity with the closely related genus Motilibacter. Based on the phenotypic, phylogenetic and chemotaxonomic data, it is proposed that the new isolate represents the nomenclature type of the novel species Vallicoccus soli gen. nov., sp. nov. (YIM 75000T = DSM 45377T = KCTC 49228T = CGMCC 1.13844T) which is the nomenclature type of the novel genus Vallicoccus gen. nov. within Vallicoccaceae fam. nov and Motilibacterales ord. nov in the phylum Actinobacteria. The family Vallicoccaceae fam. nov. and the order Motilibacterales (contains Vallicoccaceae fam. nov. and Motilibacteraceae Lee 2013) ord. nov. are formally proposed.


Asunto(s)
Actinobacteria , Suelo , Actinobacteria/genética , Técnicas de Tipificación Bacteriana , China , ADN Bacteriano/genética , Ácidos Grasos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2
5.
Pak J Med Sci ; 36(5): 977-981, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32704274

RESUMEN

OBJECTIVE: To explore the role of musculoskeletal ultrasound (MSUS) in the differential diagnosis of gouty arthritis (GA) and rheumatoid arthritis (RA) and to analyze the ultrasound imaging features of the two diseases. METHODS: A retrospective study was carried out. A total of 66 patients who had been admitted to The First Medical Center of Chinese PLA General Hospital from May 2018 to March 2019 were enrolled. Among them, 34 patients were diagnosed with RA and were included in the RA group; 32 patients were diagnosed with gouty arthritis and were included in the GA group. The imaging features of musculoskeletal ultrasound were compared between the two groups of patients. RESULTS: A total of 34 patients were included in the RA group, including 17 males and 17 females. A total of 32 patients were included in the GA group, including 14 males and 18 females. There were no significant differences in gender composition, age, and duration of disease between the two groups (P>0.05). In the RA group, there were joint bone erosions with a clear boundary in seven cases and with a blurred boundary in 27 cases; synovial hyperplasia was observed in 27 cases, and point-like hyperechoic masses were observed in four cases. In the GA group, there were joint bone erosions with a clear boundary in 27 cases and with a blurred boundary in five cases; synovial hyperplasia was observed in four cases, tophus was observed in 23 cases, point-like hyperechoic masses were observed in 27 cases, and the tram-track sign was observed in 23 cases. The differences in bone erosion boundaries (c2=26.854, P<0.01), synovial hyperplasia (c2=29.631, P<0.01), tophus (P<0.01), point-like hyperechoic mass (c2=33.095, P<0.01), and tram-track sign (P<0.01) were statistically significant between the two groups of patients. In the RA group, blood flow signaling was Grade 0 in one case, Grade-I in five cases, Grade-II in 14 cases, and Grade-III in 14 cases. In the GA group, blood flow signaling was Grade 0 in 26 cases, Grade-I in three cases, Grade-II in three cases, and Grade-III in zero cases. The difference in the synovial blood flow signaling between the two groups of patients was statistically significant (c2=34.323, P<0.01). CONCLUSIONS: MSUS has certain diagnostic value in the differentiation of GA and RA. Moreover, the two conditions have their own ultrasound imaging features.

6.
Int J Syst Evol Microbiol ; 69(7): 1903-1909, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31046875

RESUMEN

A Gram-positive, aerobic, non-motile actinobacterium, designated YIM 75507T, that was isolated from a soil sample collected from a dry-hot valley, was subjected to a polyphasic taxonomic study. The isolate formed branched hyphae and no fragmentation was found. Clustered spore chains were borne from aerial mycelium. The cell-wall peptidoglycan contained glutamic acid, alanine and meso-diaminopimelic acid. Whole-cell sugars were galactose, mannose, glucosamine, glucose and ribose. The major menaquinones were MK-9(H6), MK-9(H8) and MK-10(H6). The polar phospholipids contained phosphatidylmethylethanolamine, phosphatidylethanolamine and ninhydrin-positive phosphoglycolipid. Major fatty acids were iso-C16 : 0 and 10-methyl-C17 : 0. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM 75507T formed a stable and distinct lineage clustered with the genus Sinosporangium in the family Streptosporangiaceae. The draft genome sequence of strain YIM 75507T exhibited low average nucleotide identity to the closest related strain, Sinosporangium album CPCC 201354T (83.97 %), well below the 95-96 % species circumscription threshold. The G+C content of the genomic DNA was 73.8 mol%. On the basis of morphological, chemotaxonomic and phylogenetic evidence, strain YIM 75507T is assigned to a novel species of a new genus, for which the name Bailinhaonella thermotolerans gen. nov., sp. nov. is proposed. The type strain of Bailinhaonella thermotolerans is YIM 75507T (=KCTC 49229T=CGMCC 4.7547T).


Asunto(s)
Actinomycetales/clasificación , Filogenia , Microbiología del Suelo , Actinomycetales/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , Pared Celular/química , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Peptidoglicano/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/química
7.
Int J Syst Evol Microbiol ; 69(2): 384-389, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30543502

RESUMEN

A novel halophilic actinobacterial strain, designated YIM 96934T, was isolated from a soil sample collected from the edge of a saline lake in Xinjiang, north-west China. The taxonomic position of the strain was investigated using a polyphasic approach. Cells of the strain were aerobic and Gram-stain-positive. On the basis of 16S rRNA gene sequence analysis, strain YIM 96934T was related most closely to type strains of the genus Phytoactinopolyspora, and shared highest sequence similarity with Phytoactinopolyspora endophytica EGI 60009T (94.7 %), Phytoactinopolyspora alkaliphila EGI 80629T (94.5 %) and Phytoactinopolyspora halotolerans YIM 96448T (94.1 %). Optimum growth of the strain was observed at 28-37 °C (range 15-45 °C), pH 7.0-8.0 (6.0-9.0) and 5-8 % (w/v) NaCl (2-24 %). The major isoprenoid quinone was MK-9(H4). The whole-cell sugars were glucose, galactose, mannose and rhamnose. The diagnostic diamino acid was ll-diaminopimelic acid. The polar lipid profile was found to consist of diphosphatidylglycerol, four unidentified phospholipids, three unidentified phosphoglycolipids, an unidentified aminophospholipid, two phosphatidylinositol mannosides and an unidentified polar lipid. The major fatty acids were anteiso-C15 : 0, iso-C16 : 0, iso-C17 : 0, anteiso-C17 : 0 and summed feature 4 (iso-C17 : 1 I and/or anteiso-C17 : 1 B). The DNA G+C content was 66.6 mol%. On the basis of phenotypic, genotypic and phylogenetic data, a novel species, Phytoactinopolyspora halophila sp. nov., is proposed. The type strain is YIM 96934T (=KCTC 39926T=CCTCC AB 2017057T).


Asunto(s)
Actinobacteria/clasificación , Lagos/microbiología , Filogenia , Salinidad , Microbiología del Suelo , Actinobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
8.
Antonie Van Leeuwenhoek ; 111(1): 27-34, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28825140

RESUMEN

A novel aerobic, Gram-positive, non-motile halotolerant actinobacterium, designated strain YIM 96448T, was isolated from a saline soil sample collected from the south bank of Aiding Lake in Xinjiang Province, northwest China. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM 96448T is closely related to Phytoactinopolyspora endophytica EGI 60009T (98.0%) and Phytoactinopolyspora alkaliphila EGI 80629T (97.0%). Optimum growth of the strain was observed at 28-37 °C, pH 7-9 and in the presence of 5-8% NaCl (w/v). The respiratory quinone of strain YIM 96448T was determined to be MK-9(H4). The major fatty acids (>10%) were identified as anteiso-C15:0, iso-C16:0, anteiso-C17:0 and summed feature 4 (iso-C17:1 I and/or anteiso-C17:1B). The polar lipid profile was found to consist of diphosphatidylglycerol, an unidentified aminophospholipid, phosphatidylglycerol, two phosphatidylinositol mannosides, three unidentified phosphoglycolipids and four unidentified phospholipids. The DNA G+C content was determined to be 68.7 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic analysis, strain YIM 96448T should be classified as a novel species in the genus Phytoactinopolyspora, for which the name Phytoactinopolyspora halotolerans sp. nov. is proposed. The type strain is YIM 96448T (=CCTCC AB 2017055T = KCTC 39924T).


Asunto(s)
Actinobacteria/clasificación , Salinidad , Microbiología del Suelo , Suelo/química , Actinobacteria/química , Actinobacteria/genética , Actinobacteria/aislamiento & purificación , China , Metabolómica/métodos , Fenotipo , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
9.
Chin J Nat Med ; 13(6): 438-44, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26073340

RESUMEN

In our previous study, we have elucidated the chemical profile of YGS40, a fraction of Yi-Gan San (YGS), used for the treatment of Alzheimer's disease (AD). Oxidative stress-induced apoptosis is implicated in neurodegenerative disorders such as AD. The aim of the present study was to explore the protective effects of YGS40 against hydrogen peroxide (H2O2)-induced apoptosis in PC12 cells and the underlying mechanisms. PC12 cells were exposed to 100 µmol·L(-1) of H2O2 for 12 h with or without YGS40 pretreatment. Cytotoxicity was determined by MTT (3, (4, 5-dimethylthiazole-2-yl) 2, 5-diphenyl-tetrazolium bromide) and lactate dehydrogenase (LDH) release assays; apoptosis was detected by Annexin V/propidium iodide coupled staining and by determining caspase-3 activity and Bax and Bcl-2 protein levels. Mitochondrial membrane potential (MMP) was assessed by the retention of rhodamine123; and the activities of superoxide dismutase (SOD) and malondialdehyde (MDA) were measured using commercially available enzymatic kits. Pretreatment with YGS40 significantly prevented H2O2-induced cytotoxicity and protected the cells against H2O2-triggered apoptosis characterized by externalization of membrane phosphatidylserine and caspase-3 activation and the increased ratio of Bax/Bcl-2 in PC12 cells. Further studies showed that YGS40 suppressed H2O2-induced MMP loss, increased SOD activity, and decreased MDA level. These findings suggest that YGS40 may be beneficial for the prevention and treatment of oxidative stress-mediated disorders.


Asunto(s)
Apoptosis/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Peróxido de Hidrógeno/toxicidad , Fármacos Neuroprotectores/farmacología , Animales , Antioxidantes/farmacología , Caspasa 3/metabolismo , Supervivencia Celular/efectos de los fármacos , Malondialdehído/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/enzimología , Mitocondrias/metabolismo , Estrés Oxidativo/efectos de los fármacos , Células PC12 , Ratas , Especies Reactivas de Oxígeno/metabolismo
10.
World J Gastroenterol ; 19(14): 2270-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23599655

RESUMEN

AIM: To study non-cardiac chest pain (NCCP) in relation to ineffective esophageal motility (IEM) and rapid food intake. METHODS: NCCP patients with a self-reported habit of fast eating underwent esophageal manometry for the diagnosis of IEM. Telephone interviews identified eating habits of additional IEM patients. Comparison of manometric features was done among IEM patients with and without the habit of rapid food intake and healthy controls. A case study investigated the effect of 6-mo gum chewing on restoration of esophageal motility in an IEM patient. The Valsalva maneuver was performed in IEM patients and healthy controls to assess the compliance of the esophagus in response to abdominal pressure increase. RESULTS: Although most patients diagnosed with NCCP do not exhibit IEM, remarkably, all 12 NCCP patients who were self-reporting fast eaters with a main complaint of chest pain (75.0%) had contraction amplitudes in the mid and distal esophagus that were significantly lower compared with healthy controls [(23.45 mmHg (95%CI: 14.06-32.85) vs 58.80 mmHg (95%CI: 42.56-75.04), P < 0.01 and 28.29 mmHg (95%CI: 21.77-34.81) vs 50.75 mmHg (95%CI: 38.44-63.05), P < 0.01, respectively)]. In 7 normal-eating IEM patients with a main complaint of sensation of obstruction (42.9%), the mid amplitude was smaller than in the controls [30.09 mmHg (95%CI: 19.48-40.70) vs 58.80 mmHg (95%CI: 42.56-75.04), P < 0.05]. There was no statistically significant difference in manometric features between the fast-eating and normal-eating groups. One NCCP patient who self-reported fast eating and was subsequently diagnosed with IEM did not improve with proton-pump inhibition but restored swallow-induced contractions upon 6-mo gum-chewing. The Valsalva maneuver caused a markedly reduced pressure rise in the mid and proximal esophagus in the IEM patients. CONCLUSION: Habitual rapid food intake may lead to IEM. A prospective study is needed to validate this hypothesis. Gum-chewing might strengthen weakened esophageal muscles.


Asunto(s)
Dolor en el Pecho/etiología , Ingestión de Alimentos , Trastornos de la Motilidad Esofágica/complicaciones , Esófago/fisiopatología , Adulto , Estudios de Casos y Controles , Dolor en el Pecho/diagnóstico , Goma de Mascar , Deglución , Trastornos de la Motilidad Esofágica/diagnóstico , Trastornos de la Motilidad Esofágica/fisiopatología , Trastornos de la Motilidad Esofágica/terapia , Femenino , Humanos , Masculino , Manometría , Masticación , Persona de Mediana Edad , Fuerza Muscular , Valor Predictivo de las Pruebas , Recuperación de la Función , Factores de Tiempo , Resultado del Tratamiento , Maniobra de Valsalva , Adulto Joven
11.
Langmuir ; 28(9): 4283-92, 2012 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-22329614

RESUMEN

In this paper, a series of poly(styrene-b-isoprene-b-styrene) triblock copolymers (SIS), with different chemical components, was synthesized by anionic polymerization. The relationships between surface structures of these block copolymers and their stick-slip phenomena were investigated. There is a transition from stick-slip to a closely smooth motion for the SIS films with increasing PS content; the patterns almost vanish and the three-phase line appears to move overall smoothly on the film surface. The results show that the observed stick-slip pattern is strongly dependent on surface viscoelasticity. The jumping angle Δθ, which is defined as θ(1) - θ(2) (when a higher limit to θ(1) is obtained, the triple line "jumps" from θ(1) to θ(2) with increases in drop volume), was employed to scale the stick-slip behavior on various SIS film surfaces. Scanning force microscopy/atomic force microscopy (AFM) and sum frequency generation methods were used to investigate the surface structures of the films and the contributions of various possible factors to the observed stick-slip behavior. It was found that there is a linear relationship between jumping angle Δθ and the slope of the approach curve obtained from AFM force measurement. This means that the stick-slip behavior may be attributed mainly to surface viscoelasticity for SIS block copolymers. The measurement of jumping angle Δθ may be a valuable method for studying surface structure relaxation of polymer films.


Asunto(s)
Butadienos/química , Hemiterpenos/química , Pentanos/química , Polímeros/química , Estireno/química , Elasticidad , Propiedades de Superficie , Viscosidad
12.
Fa Yi Xue Za Zhi ; 24(4): 262-4, 267, 2008 Aug.
Artículo en Chino | MEDLINE | ID: mdl-18817035

RESUMEN

OBJECTIVE: To detect DNA polymorphism of Papaver somniferum L using fluorescent Amplified Fragment Length Polymorphism. METHODS: Genomic DNA was isolated using the AxyPrep DNA Kit, double-digested by two restrictional endonucleases (Eco RI and Mse I) and ligated to oligonucleotide adapters. After Pre-amplification and selective amplification, the DNA fragments were separated by capillary electrophoresis using the CEQ8000 DNA Fragment Analyzer. RESULTS: More than 20 fragments of highly polymorphic products were obtained by 8 pairs of primer from 64 selective amplifying primer pairs. CONCLUSION: The fluorescent AFLP technique can be used to detect the DNA polymorphism of Papaver somniferum.


Asunto(s)
Análisis del Polimorfismo de Longitud de Fragmentos Amplificados/métodos , ADN de Plantas/genética , Papaver/genética , Polimorfismo Genético , ADN de Plantas/análisis , Colorantes Fluorescentes , Genética Forense
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