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1.
Phys Rev Lett ; 131(24): 242501, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38181133

RESUMEN

We report here the first observation of the 0_{2}^{+} state of ^{8}He, which has been predicted to feature the condensatelike α+^{2}n+^{2}n cluster structure. We show that this state is characterized by a spin parity of 0^{+}, a large isoscalar monopole transition strength, and the emission of a strongly correlated neutron pair, in line with theoretical predictions. Our finding is further supported by the state-of-the-art microscopic α+4n model calculations. The present results may lead to new insights into clustering in neutron-rich nuclear systems and the pair correlation and condensation in quantum many-body systems under strong interactions.

2.
Artículo en Zh | MEDLINE | ID: mdl-34074075

RESUMEN

Objective: To analyze the clinical characteristics of pesticide poisoning patients and explore the risk factors of acute kidney injury (AKI) . Methods: In September 2020, the clinical data of 155 patients with pesticide poisoning in the department of nephropathy, the Affiliated Hospital of Southwest Medical University from September 2018 to August 2020 were retrospectively analyzed. The patients were divided into AKI group (44 cases) and non AKI group (111 cases) according to the occurrence of AKI. The clinical characteristics, organ or system involvement and auxiliary examination results of the two groups were analyzed. Logistic regression was used to analyze the risk factors of AKI in patients with pesticide poisoning. Results: The types of pesticides causing poisoning mainly included herbicides, insecticides and biochemical pesticides. Compared with non AKI group, patients in AKI group had higher proportion of blood purification treatment and ICU monitoring treatment (P<0.05) , and were more likely to be complicated with acute respiratory failure, pulmonary fibrosis, myocardial injury, multiple organ dysfunction syndrome (MODS) , acute pancreatitis and coagulation abnormalities (P<0.05) . The mortality of AKI group (18.2%, 8/14) was significantly higher than that of non AKI group (0.9%, 1/111) (P<0.05) . Univariate analysis showed that the time from poisoning to treatment > 6 h, high WBC count, neutrophil count, alanine aminotransferase, aspartate aminotransferase, high sensitive troponin T, myoglobin and creatine kinase isoenzyme were the risk factors of AKI in patients with pesticide poisoning (P<0.05) . Multivariate logistic regression analysis showed that the time from poisoning to treatment >6 h was an independent risk factor for AKI in patients with pesticide poisoning (P<0.05) . Conclusion: The mortality of AKI secondary to pesticide poisoning is high. Attention should be paid to the time from poisoning to treatment, inflammatory state and changes of liver and myocardial function.


Asunto(s)
Lesión Renal Aguda , Pancreatitis , Plaguicidas , Enfermedad Aguda , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/epidemiología , Humanos , Pronóstico , Estudios Retrospectivos , Factores de Riesgo
3.
Scand J Rheumatol ; 49(2): 146-153, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31538512

RESUMEN

Objectives: Scleroderma is a connective tissue immune disease that features collagen overproduction and can be categorized into two subtypes, localized scleroderma (LSc) and systemic sclerosis (SSc). SSc is clinically classified into two subsets: limited cutaneous (lcSSc) and diffuse cutaneous (dcSSc) SSc. The immunoglobulin G-galactosylation (IgG-Gal) ratio is abnormal in a number of immune diseases and has not been evaluated in SSc.Method: The study recruited 93 LSc patients, 298 SSc patients, and 436 healthy controls. N-glycans of purified IgG were obtained from plasma and detected by tandem mass spectrometry. The IgG-Gal ratio was measured by calculating the relative intensities of agalactosylated (G0), monogalactosyl (G1), and digalactosyl (G2) N-glycans according to the formula G0/(G1 + G2 × 2). Furthermore, we examined whether the IgG-Gal ratio differed between different subtypes of SSc.Results: The IgG-Gal ratio was significantly higher in SSc patients (1.139 ± 0.870) than in LSc patients (0.485 ± 0.280) and controls (0.395 ± 0.190). The IgG-Gal ratio successfully distinguished SSc patients from LSc and controls (area under the curve = 0.88 and 0.81, respectively). The IgG-Gal ratio was significantly higher in dcSSc patients than in lcSSc patients and increased along with increases in modified Rodnan skin score (p = 6.03 × 10-5, Pearson's coefficient = 0.26) and erythrocyte sedimentation rate (p = 2.95 × 10-10, Pearson's coefficient = 0.38).Conclusion: IgG-Gal ratios were abnormal in SSc patients and were associated with disease severity. The IgG-Gal ratio therefore shows potential as a biomarker for the diagnosis of SSc.


Asunto(s)
Galactosa/metabolismo , Inmunoglobulina G/metabolismo , Esclerodermia Sistémica/inmunología , Adulto , Sedimentación Sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerodermia Localizada/inmunología , Esclerodermia Sistémica/diagnóstico , Esclerodermia Sistémica/metabolismo
4.
J Appl Microbiol ; 128(3): 784-793, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31651063

RESUMEN

AIMS: To develop a pcsB-based Loop-mediated isothermal amplification (LAMP) method for the detection of Streptococcus agalactiae (GBS) in milk, tilapia and vaginal swabs. METHODS AND RESULTS: The sensitivity of the LAMP method using real-time turbidity monitoring was 1 pg of template within 1 h at 64°C, 100-fold higher than conventional PCR. The sensitivity of visual detection dropped an order of magnitude using SYBR Green I or hydroxynaphthol blue. The validity of the visual LAMP assay was assessed by the detection of GBS in 180 vaginal swabs from one hospital, 14 brain tissues samples of diseased tilapias from two fishponds and fresh milk of 67 dairy cattle from one farm. In total, 17 samples (4 vaginal swabs, 13 tilapia brain tissues but no milk sample) tested positive for GBS. Subsequent bacterial identification confirmed the specificity and reliability of the LAMP method. Molecular serotyping and multilocus sequence typing demonstrated that all 13 tilapia GBS isolates were identical (serotype Ia, ST7), whereas the four human GBS isolates were more diverse and could be classified into two serotypes (Ia, III) and four sequence types (ST19, ST23, ST24, ST862). Virulence gene testing showed that only the bac, rib and lmb genes were not present in all isolates. Antimicrobial susceptibility profiles of the isolates were basically consistent with their genotypes, except for sulphonamide and fluoroquinolone. CONCLUSIONS: We developed a reliable pcsB-based LAMP assay for GBS detection. Our results demonstrated that the prevalence of GBS was 92·9% among diseased tilapia, 2·2% among female patients and 0% on a dairy farm in Hainan. SIGNIFICANCE AND IMPACT OF THE STUDY: The pcsB-based LAMP method is suitable for GBS detection and contains great potential of application in dairy industry, aquiculture and clinical.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas de Ciclo Celular/genética , Técnicas de Amplificación de Ácido Nucleico/métodos , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/aislamiento & purificación , Animales , Antibacterianos/farmacología , Técnicas de Tipificación Bacteriana , China , Femenino , Genotipo , Humanos , Pruebas de Sensibilidad Microbiana , Leche/microbiología , Tipificación de Secuencias Multilocus , Reproducibilidad de los Resultados , Serogrupo , Streptococcus agalactiae/clasificación , Streptococcus agalactiae/efectos de los fármacos , Streptococcus agalactiae/genética , Tilapia/microbiología , Vagina/microbiología , Virulencia/genética
5.
Lett Appl Microbiol ; 68(3): 212-218, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30609084

RESUMEN

Hundreds of farmed Siamese crocodiles (Crocodylus siamensis) died during July 2016 at a farm in Wenchang, Hainan, China. In two necropsied crocodiles, we observed symptoms of dermatorrhagia, hepatomegaly and hepatic congestion. Pulmonitis was diagnosed by pulmonary congestion and pulmonary fibrinous exudate. Septicaemia was diagnosed by isolation of three Aeromonas species from blood and visceral tissues; A. dhakensis, A. hydrophila and A. jandaei were identified by biochemical and molecular tests. We used a zebrafish model to determine the half-maximal lethal dose (LD50 ), and A. dhakensis was found to be the most virulent species, with an LD50 of 8·91 × 105 CFU per ml. The results of a drug sensitivity test indicated that these species were sensitive to 11 antibiotics. This is the first report of A. dhakensis, A. hydrophila and A. jandaei being isolated from a mixed infection in Siamese crocodiles. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, we isolated three species of Aeromonas (A. dhakensis, A. hydrophila and A. jandae) from farmed Siamese crocodiles with fatal fibrinous pneumonia and septicaemia. This is the first description of a mixed infection with three Aeromonas species among captive crocodilians.


Asunto(s)
Aeromonas hydrophila/clasificación , Aeromonas hydrophila/aislamiento & purificación , Caimanes y Cocodrilos/microbiología , Infecciones por Bacterias Gramnegativas/veterinaria , Neumonía/microbiología , Sepsis/microbiología , Aeromonas hydrophila/efectos de los fármacos , Aeromonas hydrophila/genética , Animales , Antibacterianos/farmacología , China , Coinfección , Girasa de ADN/genética , ARN Polimerasas Dirigidas por ADN/genética , Agua Dulce , Pruebas de Sensibilidad Microbiana , Factor sigma/genética , Pez Cebra/microbiología
6.
Zhonghua Yan Ke Za Zhi ; 53(4): 266-273, 2017 Apr 11.
Artículo en Zh | MEDLINE | ID: mdl-28412799

RESUMEN

Objective: To observe the long-term outcomes after congenital cataract surgery performed prior to 36 months of age. Methods: A retrospective case study was conducted. Thirty-two cases (57 eyes) of congenital cataract were included from January 2004 to January 2012. All patients received intraocular lens (IOL) implantation with posterior continuous curvilinear capsulorhexies and anterior vitrectomy after cataract extraction and were followed up. At the last visit, the best corrected visual acuity (BCVA) was determined and postoperative complications were evaluated during follow-up with a longest time of 13 years. Non-normal distribution showed in median M (minimum and maximum). Data were analyzed by Kruskal Wallis single factor variance analysis and multiple comparison. The independent Mann-Witney U test was used to analyze non-normal distribution data. Results: There were thirty-two cases (57 eyes) of congenital cataract including 7 unilateral cases and 25 bilateral cases. The median age at cataract extraction was 6.0months; the median IOL implantation age was 28.0 months and the median duration of follow-up after cataract extraction was 67.0 months. The median postoperative BCVA was (LogMAR) 0.52. Unilateral and bilateral cataract postoperative BCVA difference had no statistical significance (U=107, P>0.05). Patients received cataract surgery in 2 to 4 months, the postoperative BCVA was better than in 5 to 8 months. The difference was statistical significance (H=-15.33, P<0.05). BCVA after IOL implantation before 24 months were significantly better than after 30 months. The difference had statistical significance(H=-20.61,-20.78, P<0.05). Postoperative complications were posterior capsular opacity (5 eyes; 8.77%), glaucoma (2 eyes; 3.51%), strabismus (17 eyes; 29.82%) and nystagmus (30 eyes; 52.63%). Conclusions: Most infantile cataract surgeries performed prior to 36 mouths of life together with the implantation of IOL can achieve good visual acuity. No serious complications occurred. (Chin J Ophthalmol, 2017, 53: 266-273).


Asunto(s)
Extracción de Catarata , Catarata/congénito , Implantación de Lentes Intraoculares , Agudeza Visual , Extracción de Catarata/efectos adversos , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Implantación de Lentes Intraoculares/efectos adversos , Lentes Intraoculares , Masculino , Complicaciones Posoperatorias/diagnóstico , Estudios Retrospectivos , Estadísticas no Paramétricas , Factores de Tiempo , Resultado del Tratamiento , Vitrectomía/métodos
7.
Psychol Med ; 46(6): 1211-24, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26743997

RESUMEN

BACKGROUND: A large-scale network named the default mode network (DMN) dynamically cooperates and competes with an external attention system (EAS) to facilitate various cognitive functioning that is prominently impaired in schizophrenia. However, it is unclear whether the cognitive deficit in schizophrenia is related to the disrupted competition and/or cooperation between these two networks. METHOD: A total of 35 schizophrenia patients and 30 healthy controls were scanned using gradient-echo echo-planar imaging during n-back working memory (WM) processing. Brain activities of the DMN and EAS were measured using general linear modelling of the functional magnetic resonance imaging data. Dynamic interaction between the DMN and EAS was decomposed into two directions using Granger causality analysis. RESULTS: We observed a significant failure of DMN suppression in patients with schizophrenia, which was significantly related to WM/attentional deficit. Granger causality modelling showed that in healthy controls, while the EAS inhibitorily influenced the DMN, the DMN exerted an 'excitatory' or cooperative influence back on the EAS, especially in those with lower WM accuracy. In schizophrenia, this 'excitatory' DMN→EAS influence within the reciprocal EAS-DMN loop was significantly reduced, especially in patients with WM/attentional deficit. CONCLUSIONS: The dynamic interaction between the DMN and EAS is likely to be comprised of both competitive and cooperative influences. In healthy controls, both the 'inhibitory' EAS→DMN interaction and 'excitatory' DMN→EAS interaction are correlated with WM performance. In schizophrenia, reduced 'cooperative' influence from the DMN to dorsal nodes of the EAS occurs in the context of non-suppression of the DMN and may form a possible pathophysiological substrate of WM deficit and attention disorder.


Asunto(s)
Atención , Encéfalo/fisiopatología , Memoria a Corto Plazo , Red Nerviosa/fisiopatología , Esquizofrenia/fisiopatología , Conducta Social , Adolescente , Adulto , Mapeo Encefálico , Estudios de Casos y Controles , Cognición , Imagen Eco-Planar , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Modelos Neurológicos , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Adulto Joven
8.
Biochim Biophys Acta ; 1839(11): 1273-82, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24878542

RESUMEN

GATA4 is expressed in the proximal 85% of small intestine where it promotes a proximal intestinal ('jejunal') identity while repressing a distal intestinal ('ileal') identity, but its molecular mechanisms are unclear. Here, we tested the hypothesis that GATA4 promotes a jejunal versus ileal identity in mouse intestine by directly activating and repressing specific subsets of absorptive enterocyte genes by modulating the acetylation of histone H3, lysine 27 (H3K27), a mark of active chromatin, at sites of GATA4 occupancy. Global analysis of mouse jejunal epithelium showed a statistically significant association of GATA4 occupancy with GATA4-regulated genes. Occupancy was equally distributed between down- and up-regulated targets, and occupancy sites showed a dichotomy of unique motif over-representation at down- versus up-regulated genes. H3K27ac enrichment at GATA4-binding loci that mapped to down-regulated genes (activation targets) was elevated, changed little upon conditional Gata4 deletion, and was similar to control ileum, whereas H3K27ac enrichment at GATA4-binding loci that mapped to up-regulated genes (repression targets) was depleted, increased upon conditional Gata4 deletion, and approached H3K27ac enrichment in wild-type control ileum. These data support the hypothesis that GATA4 both activates and represses intestinal genes, and show that GATA4 represses an ileal program of gene expression in the proximal small intestine by inhibiting the acetylation of H3K27.


Asunto(s)
Factor de Transcripción GATA4/fisiología , Histona Acetiltransferasas/antagonistas & inhibidores , Histonas/metabolismo , Íleon/metabolismo , Acetilación , Animales , Células Cultivadas , Regulación hacia Abajo/genética , Regulación de la Expresión Génica , Histona Acetiltransferasas/metabolismo , Intestino Delgado/metabolismo , Lisina/metabolismo , Ratones , Ratones Transgénicos
9.
Dev Biol ; 353(2): 229-41, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-21385577

RESUMEN

Assembly of functioning testis and ovary requires a GATA4-FOG2 transcriptional complex. To define the separate roles for GATA4 and FOG2 proteins in sexual development of the testis we have ablated the corresponding genes in somatic gonadal cells. We have established that GATA4 is required for testis differentiation, for the expression of Dmrt1 gene, and for testis cord morphogenesis. While Sf1Cre-mediated excision of Gata4 permitted normal expression of most genes associated with embryonic testis development, gonadal loss of Fog2 resulted in an early partial block in male pathway and sex reversal. We have also determined that testis sexual differentiation is sensitive to the timing of GATA4 loss during embryogenesis. Our results now demonstrate that these two genes also have non-overlapping essential functions in testis development.


Asunto(s)
Proteínas de Unión al ADN/deficiencia , Factor de Transcripción GATA4/deficiencia , Diferenciación Sexual/fisiología , Factores de Transcripción/deficiencia , Animales , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/fisiología , Femenino , Factor de Transcripción GATA4/genética , Factor de Transcripción GATA4/fisiología , Regulación del Desarrollo de la Expresión Génica , Genes sry , Masculino , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Mutantes , Ovario/embriología , Factor de Transcripción SOX9/genética , Células de Sertoli/metabolismo , Diferenciación Sexual/genética , Testículo/embriología , Factores de Transcripción/genética , Factores de Transcripción/fisiología
10.
Artículo en Zh | MEDLINE | ID: mdl-35266358

RESUMEN

OBJECTIVE: To identify the species of trematodes isolated from laying ducks in Nanchang City using morphological and molecular approaches. METHODS: Trematodes were isolated from the hepatobiliary duct, gallbladder and large intestine of market-sold laying ducks in Nanchang City. Following morphological characterization, total DNA was extracted from all trematode specimens, and internal transcribed spacer region (ITS) and cytochrome C oxidase subunit 1 (Cox1) genes were amplified using PCR assay and sequenced. Sequence alignment was performed using the Blast software, and homology and phylogenetic analyses were done in the trematode isolates based on ITS and Cox1 gene sequences. RESULTS: The morphological characteristics of two trematode isolates from the large intestine of laying ducks were similar to those of Echinostoma revolutum and E. miyagawai, and the morphological characteristics of eight trematode samples isolated from the hepatobiliary duct and gallbladder of laying ducks were similar to those of Amphimerus anatis. The ITS and Cox1 gene sequences of the two trematode isolates from the large intestine of laying ducks had 99.3% and 98.9%-99.4% homology with E. miyagawai, and the phylogenetic analysis showed that two trematode isolates had the closest genetic relationship with E. miyagawai based on ITS and Cox1 gene sequences. The ITS gene sequences of eight trematode isolates from the hepatobiliary duct and gallbladder of laying ducks shared 95.1%-95.5% with Opisthorchis sudarikovi and Clonorchis sinensis, while the Cox1 gene sequences of eight trematode isolates from the hepatobiliary duct and gallbladder of laying ducks shared 86.3%-86.4% and 85.5%-85.7% with O. viverrini and O. sudarikovi. ITS gene sequence-based phylogenetic analysis showed that the duck-derived trematode isolates had the closest genetic relationship with C. sinensis, and Cox1 gene sequence-based phylogenetic analysis showed that the duck-derived trematode isolates had the closest genetic relationship with Metorchis orientalis and O. viverrini. CONCLUSIONS: The trematode isolates from the large intestine of laying ducts in Nanchang City may be E. miyagawai, and the trematode isolates from the hepatobiliary duct and gallbladder may be an unidentified trematode species of the family Opisthorchiidae.


Asunto(s)
Echinostoma , Opisthorchis , Animales , Patos , Echinostoma/genética , Opisthorchis/genética , Filogenia , Alineación de Secuencia
11.
Oncogene ; 26(14): 2115-25, 2007 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-17016445

RESUMEN

Synucleins are emerging as central players in the formation of pathologically insoluble deposits characteristic of neurodegenerative diseases. However, synuclein gamma (SNCG), previously identified as a breast cancer specific gene (BCSG1), is also highly associated with breast cancer progression. Using transgenic mouse model, we demonstrated a role of SNCG in induction of highly proliferative pregnancy-like phenotype of mammary epithelial cells and branching morphology. SNCG participated in the heat shock protein-based multiprotein chaperone complex for steroid receptor signaling. Expression of SNCG in mammary epithelium resulted in a significant stimulation of ERalpha transcriptional activity. SNCG-induced mammary gland proliferation can be effectively blocked by antiestrogen and ovariectomy, indicating that the induced proliferation is mediated by ERalpha signaling and requires estrogen stimulation. These data indicate the chaperone activity of SNCG on stimulation of steroid receptor signaling in mammary gland and, thus induces extensive mammary gland proliferation and contributes to the hormonal impact on mammary tumorigenesis.


Asunto(s)
Receptor alfa de Estrógeno/metabolismo , Glándulas Mamarias Humanas/patología , Neoplasias Mamarias Animales/patología , Chaperonas Moleculares/metabolismo , gamma-Sinucleína/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Receptor alfa de Estrógeno/antagonistas & inhibidores , Estrógenos/metabolismo , Humanos , Glándulas Mamarias Humanas/metabolismo , Neoplasias Mamarias Animales/genética , Neoplasias Mamarias Animales/metabolismo , Ratones , Ratones Transgénicos , Neuronas/metabolismo , Transcripción Genética , gamma-Sinucleína/genética
12.
Mol Cell Biol ; 11(10): 4918-26, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1922025

RESUMEN

Yeast GCN4 and the Jun oncoprotein are transcriptional activators that bind DNA via a bZIP domain consisting of a leucine zipper dimerization element and an adjacent basic region that directly contacts DNA. Two highly conserved alanines (Ala-238 and Ala-239 in GCN4) and an invariant asparagine (Asn-235) in the basic region have been proposed to play important roles in DNA sequence recognition by bZIP proteins. Surprisingly, these conserved residues can be functionally replaced in GCN4 and in a derivative containing the Jun basic region (Jun-GCN4). The ability of an amino acid to functionally substitute for Asn-235 does not correlate with its preference for assuming the N-cap position of an alpha helix. This finding argues against the proposal of the scissors grip model that the invariant asparagine forms an N cap that permits the basic region to bend sharply and wrap around the DNA. In contrast to a prediction of the induced fork model, the pattern of functional substitutions of the conserved alanines together with the results of uracil interference experiments suggests that Ala-238 and Ala-239 do not make base-specific DNA contacts. Finally, the Jun-GCN4 chimeric proteins appear much more active in vivo than expected from their DNA-binding properties in vitro. The mechanistic and evolutionary implications of these results are discussed.


Asunto(s)
ADN de Hongos/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas Fúngicas/metabolismo , Leucina Zippers/fisiología , Proteínas Quinasas , Proteínas de Saccharomyces cerevisiae , Factores de Transcripción/metabolismo , Alanina/metabolismo , Secuencia de Aminoácidos , Asparagina/metabolismo , Secuencia de Bases , Evolución Biológica , Análisis Mutacional de ADN , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Leucina Zippers/genética , Datos de Secuencia Molecular , Proteína Oncogénica p65(gag-jun)/genética , Conformación Proteica , Proteínas Recombinantes de Fusión/metabolismo , Alineación de Secuencia , Factores de Transcripción/química , Factores de Transcripción/genética , Uracilo/metabolismo , Levaduras/genética
13.
Mol Cell Biol ; 19(6): 4113-20, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10330151

RESUMEN

The U1, U2, U4, U5, and U6 small nuclear ribonucleoproteins (snRNPs) form essential components of spliceosomes, the machinery that removes introns from pre-mRNAs in eukaryotic cells. A critical initial step in the complex process of snRNP biogenesis is the assembly of a group of common core proteins (Sm proteins) on spliceosomal snRNA. In this study we show by multiple independent methods that the protein pICln associates with Sm proteins in vivo and in vitro. The binding of pICln to Sm proteins interferes with Sm protein assembly on spliceosomal snRNAs and inhibits import of snRNAs into the nucleus. Furthermore, pICln prevents the interaction of Sm proteins with the survival of motor neurons (SMN) protein, an interaction that has been shown to be critical for snRNP biogenesis. These findings lead us to propose a model in which pICln participates in the regulation of snRNP biogenesis, at least in part by interfering with Sm protein interaction with SMN protein.


Asunto(s)
Canales de Cloruro/fisiología , Canales Iónicos , Ribonucleoproteínas Nucleares Pequeñas/biosíntesis , Ribonucleoproteínas Nucleares Pequeñas/metabolismo , Empalmosomas/fisiología , Animales , Western Blotting , Núcleo Celular/metabolismo , Citosol/metabolismo , Inmunoquímica , Modelos Biológicos , Oocitos/metabolismo , Unión Proteica , Proteínas Recombinantes de Fusión , Proteínas de Xenopus , Xenopus laevis/metabolismo
14.
Trop Biomed ; 34(4): 1014-1024, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33592972

RESUMEN

The present study provides the first report on the molecular epidemiological data regarding infection by hemoplasma and piroplasma species in wild Rattus edwardsi, from China. In the current study, blood samples were investigated from 32 wild Rattus edwardsi from Hunan (23) and Guangxi (9) provinces, China. The prevalence of hemoplasma and piroplasma was 65.63% (21/32) and 6.25% (2/32), respectively. Phylogenetic analyses indicated that hemoplasmas (HQ183731, HQ183732) derived from wild Rattus edwardsi in China, can be grouped into a solitary clade closely related to H. muris (HMU82963) and M. haemomuris (AB758435). In addition, it was shown that piroplasmas from this study have very close genetic distance to other unidentified piroplasma species isolated from China (AB242140) and Japan (AB188086). The results suggested that hemoplasmas isolated in this study should be represented as a new genotype. Piroplasmas on the other hand needs more sequenced samples in its life-cycle and evidence to check its taxonomic status. These data may have important implications for researching on the epidemiology and population biology as well as for studying the taxonomy status of hemoplasmas and piroplasmids of wild rodents.

15.
Biochim Biophys Acta ; 657(1): 203-11, 1981 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-7213744

RESUMEN

The pH-dependence of fumarylacetoacetase (4-fumarylacetoacetate fumaryl-hydrolase, EC 3.7.1.2) activity was studied in the pH range 6.25-8.50. After correction of the substrate concentration for enolate formation, the Michealis constant was found to be pH independent in this range. Likewise, the Ki values for the competitive inhibitors chloride and fluoride were found to be independent of pH between 6.25-8.50. A bell-shaped curve described the log V vs. pH dependence, and ionization constants of 6.5 and 8.2 were calculated. Tentatively an imidazole group and a sulfhydryl group were assigned to the constants 6.5 and 8.2, respectively. Both p-hydroxymercuribenzoate and 5,5'-dithiobis(2-nitrobenzoic acid) react with both sulfhydryl groups per subunit in the native protein and three sulfhydryl groups per subunit in the denatured protein. Substrate protects one sulfhydryl group in the native protein from reaction with 5,5'-dithiobis(2-nitrobenzoid acid). Substrate or the competitive inhibitor, fluoride, protect the enzyme from inactivation by p-hydroxymercuribenzoate. In addition p-hydroxymercuribenzoate shows saturation kinetics. Neither sulfhydryl inhibitor completely inactivates the enzyme. The enzyme is described as having three sulfhydryl groups per subunit, one of which is inaccessible to the sulfhydryl specific reagents when the protein is in the native state. One of the two accessible sulfhydryl groups is either near the active site or essential in maintaining the structure of the protein.


Asunto(s)
Hidrolasas/metabolismo , Reactivos de Sulfhidrilo/farmacología , Acetoacetatos/antagonistas & inhibidores , Acetoacetatos/metabolismo , Animales , Bovinos , Ácido Ditionitrobenzoico/farmacología , Fumaratos/antagonistas & inhibidores , Fumaratos/metabolismo , Concentración de Iones de Hidrógeno , Hidrolasas/antagonistas & inhibidores , Hidroximercuribenzoatos/farmacología , Cinética , Hígado/enzimología
16.
J Am Coll Cardiol ; 37(8): 2136-43, 2001 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-11419900

RESUMEN

OBJECTIVES: We sought to study the role of I(KACh) in atrial fibrillation (AF) and the potential electrophysiologic effects of a specific I(KACh) antagonist. BACKGROUND: I(KACh) mediates much of the cardiac responses to vagal stimulation. Vagal stimulation predisposes to AF, but the specific role of I(KACh) in the generation of AF and the electrophysiologic effects of specific I(KACh) blockade have not been studied. METHODS: Adult wild-type (WT) and I(KACh)-deficient knockout (KO) mice were studied in the absence and presence of the muscarinic receptor agonist carbachol. The electrophysiologic features of KO mice were compared with those of WT mice to assess the potential effects of a specific I(KACh) antagonist. RESULTS: Atrial fibrillation lasting for a mean of 5.7+/-11 min was initiated in 10 of 14 WT mice in the presence of carbachol, but not in the absence of carbachol. Atrial arrhythmia could not be induced in KO mice. Ventricular tachyarrhythmia could not be induced in either type of mouse. Sinus node recovery times after carbachol and sinus cycle lengths were shorter and ventricular effective refractory periods were greater in KO mice than in WT mice. There was no significant difference between KO and WT mice in AV node function. CONCLUSIONS: Activation of I(KACh) predisposed to AF and lack of I(KACh) prevented AF. It is likely that I(KACh) plays a crucial role in the generation of AF in mice. Specific I(KACh) blockers might be useful for the treatment of AF without significant adverse effects on the atrioventricular node or the ventricles.


Asunto(s)
Fibrilación Atrial/fisiopatología , Activación del Canal Iónico/fisiología , Canales de Potasio de Rectificación Interna , Canales de Potasio/fisiología , Animales , Carbacol/farmacología , Agonistas Colinérgicos/farmacología , Modelos Animales de Enfermedad , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Canales de Potasio Rectificados Internamente Asociados a la Proteína G , Ratones , Ratones Noqueados
17.
Am J Cardiol ; 78(6): 723-7, 1996 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-8831422

RESUMEN

The diagnostic, developmental, and surgical aspects of left pulmonary artery sling associated with right lung agenesis in 3 patients are described. Cardiac catheterization may be avoided by the combined use of echocardiography and magnetic resonance imaging and/or computed tomography.


Asunto(s)
Anomalías Múltiples/diagnóstico , Anomalías Múltiples/cirugía , Pulmón/anomalías , Arteria Pulmonar/anomalías , Anomalías Múltiples/diagnóstico por imagen , Ecocardiografía Doppler en Color , Humanos , Recién Nacido , Tomografía Computarizada por Rayos X
18.
Chin Med J (Engl) ; 113(8): 743-6, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11776061

RESUMEN

OBJECTIVE: To study the primary mutations of mitochondrial DNA (mtDNA) associated with Leber's hereditary optic neuropathy (LHON) in patients with optic neuropathy. METHODS: Seventy-nine patients with a variety of bilateral optic neuropathies were examined. Mutations at np3460, np11,778 and np14,484 of mtDNA were tested by PCR-restriction detection in peripheral blood DNA from 16 cases of clinically probable LHON, 44 cases of possible LHON, 2 cases of alcohol amblyopia, 4 cases of multiple sclerosis, 5 cases of autosomal dominant optic atrophy, 4 cases of primary open-angle glaucoma, 3 cases of spinocerebellar degeneration, and 1 case of ethambutol-induced optic neuropathy. RESULTS: The mutation at np11778 was identified in 31 cases (39.2%) to establish LHON, which consisted of: all 16 of clinically probable LHON cases, 13 cases (29.5%) of possible LHON, and 2 cases of alcohol amblyopia. The remaining 48 cases were negative for mtDNA mutations at np3460, np11 778, and np14,484. CONCLUSION: Assessment of mtDNA provides a useful diagnostic aid in the definition and exclusion of LHON, in particular family history-negative, otherwise undefined bilateral optic nerve inflammatory disease.


Asunto(s)
ADN Mitocondrial/genética , Enfermedades del Nervio Óptico/diagnóstico , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Nervio Óptico/genética , Mutación Puntual , Reacción en Cadena de la Polimerasa
19.
Zhonghua Yan Ke Za Zhi ; 37(3): 174-7, 2001 May.
Artículo en Zh | MEDLINE | ID: mdl-11864415

RESUMEN

OBJECTIVE: To study the primary mutations of mitochondrial DNA (mtDNA) associated with Leber's hereditary optic neuropathy (LHON) in patients with optic neuropathy. METHODS: Seventy-nine patients with a variety of bilateral optic neuropathy were examined. Mutations at np 3,460, np 11,778 and np 14,484 of mtDNA were tested by PCR-restriction fragment length polymorphism technique to detect DNA in peripheral blood. The samples were taken from 16 cases of clinically diagnosed LHON, 44 cases of suspected LHON, two cases of alcohol amblyopia, four cases of multiple sclerosis, five cases of autosomal dominant hereditary optic atrophy, 4 cases with primary open-angle glaucoma, three cases of spinocerebellar degeneration, and one case of ethambutol-induced optic neuropathy. RESULTS: The mutation at np 11,778 was identified in 31 cases (39.2%), consisting of all the 16 clinically diagnosed LHON cases, thirteen cases (29.5%) of the suspected LHON, and the two cases of alcohol amblyopia. The remaining 48 cases were negative for mtDNA mutations at np 3,460, np 11,778, or np 14,484. CONCLUSION: Assessment of mtDNA provides a useful diagnostic aid in confirming and excluding the diagnosis of LHON, particularly useful in cases without a family hereditary history and cases with cause unknown bilateral optic neuritis.


Asunto(s)
ADN Mitocondrial/genética , Atrofia Óptica Hereditaria de Leber/genética , Adulto , Enzimas de Restricción del ADN/metabolismo , ADN Mitocondrial/metabolismo , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Atrofia Óptica Hereditaria de Leber/diagnóstico , Mutación Puntual , Polimorfismo de Longitud del Fragmento de Restricción
20.
Zhonghua Yan Ke Za Zhi ; 34(1): 68-70, 1998 Jan.
Artículo en Zh | MEDLINE | ID: mdl-11877160

RESUMEN

OBJECTIVE: The study was designed to investigate the effects of biomembrane on experimental trabeculectomy. METHODS: A biomembrane was implanted under the scleral flap and the conjunctival flap in trabeculectomy in one eye of rabbits, while the fellow eye of the same rabbit without biomembrane implantation was the control. RESULTS: (1) The wound healing of the procedure reached its peak at 2-3 weeks after surgery, while the absorption of the biomembrane began at 6 weeks after surgery, and there was no tight adhesion between the biomembrane and the scar tissue, thus the filtering fistula was prevented from obstruction. (2) From the 2nd to the 7th week after surgery, the percentage of existing functional bleb in the experimental group was significantly higher than that in the control group (P < 0.05). (3) From the 1st to the 5th postoperative week, the decreasing of intraocular pressure in the experimental group was significantly greater than that in the control group (P < 0.05). CONCLUSION: The use of biomembrane in trabeculectomy can prevent the adhesion of filtering bleb and decrease intraocular pressure more effectively, and this study can provide experimental reference for the clinical use of biomembrane.


Asunto(s)
Glaucoma/cirugía , Membranas Artificiales , Adherencias Tisulares/prevención & control , Trabeculectomía/efectos adversos , Animales , Femenino , Glaucoma/patología , Presión Intraocular , Masculino , Microscopía Electrónica , Conejos , Cicatrización de Heridas
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