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1.
Eur Rev Med Pharmacol Sci ; 27(6): 2189-2199, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-37013736

RESUMEN

OBJECTIVE: Previous trials demonstrated the effectiveness of exercise in improving pain and functional impairment in patients with knee osteoarthritis (KOA). However, a bibliometric analysis of top-cited papers on exercise treatment for KOA has not yet been conducted. The aim of the present study was to critically analyze the bibliometric characteristics of the most frequently cited articles on exercise treatment for KOA. MATERIALS AND METHODS: Publications about exercise treatment for KOA from 2000 to 2021 were searched from the Web of Science database. Two authors independently collected 100 top-cited articles, and a consensus was reached to form the final list. The title, journal, author, year of publication, country and institution of origin, total citations, citations in 2021, main topics, research nature, and level of evidence were extracted, and the publication trends in exercise treatment for KOA were evaluated. RESULTS: A total of 1,258 papers were retrieved from the database. According to the final list, clinical research accounted for 81% of the studies, but no statistical difference in the number of citations was found among the four types of articles (p=0.194). Seventy articles had a level of evidence of Ib, and no statistical differences in citations were found per level of evidence (p=0.767). Most of the top-cited articles were published between 2005-2014, and Dr Messier was the prominent writer in this field. CONCLUSIONS: This bibliometric study is the first to identify the most cited papers in exercise treatment for KOA research. Traditional Chinese exercise, comorbidity, and exercise adherence may be the next popular research trends that will receive more attention in the future.


Asunto(s)
Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Rodilla/terapia , Bibliometría , Bases de Datos Factuales
2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(9): 1378-1380, 2020 Sep 10.
Artículo en Chino | MEDLINE | ID: mdl-33076587

RESUMEN

Biosafety is an important guarantee of the new coronavirus laboratory test. The accident treatment of sample overflow and sprinkle is a necessary part of the emergency plan for testing activities. Beijing Preventive Medicine Association coordinated biosafety experts of COVID-19 laboratories from Beijing CDC, to write up "The standard for handling of accidents of corona virus disease 2019 sample (T/BPMA 0005-2020)" . The group standard was based on the guidelines of China and WHO, and combined with the practical experience of COVID-19 epidemic and the principle of "scientific, normative, applicable and feasible" . Through all kinds of risk Assessment, it included the spillover of samples caused by the packing of COVID-19 (highly pathogenic) samples, the overflow and sprinkle in the laboratory during the detection operation, and the spillage accident occurred during the transfer of samples in the same building. The standard could guide and standardize the handling methods of accidental overflow and sprinkle that may occur in the SARS-CoV-2 testing laboratories in the city.


Asunto(s)
Derrame de Material Biológico , Técnicas de Laboratorio Clínico , Contención de Riesgos Biológicos/normas , Beijing , Prueba de COVID-19 , Infecciones por Coronavirus/diagnóstico , Humanos
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(2): 175-180, 2020 Feb 06.
Artículo en Chino | MEDLINE | ID: mdl-32074706

RESUMEN

Objective: To analyze the molecular characteristics of Listeria monocytogenes strains from ready-to eat food in China. Methods: A total of 239 Listeria monocytogenes strains isolated from ready-to-eat food in 2017, all strains underwent whole-genome sequencing (WGS) , and comparisons uncovered population structure derived from lineages, clonal complex, serogroups, antimicrobial susceptibility and virulence, which were inferred in silico from the WGS data. Core genome multilocus sequence typing was used to subtype isolates. Results: All strains were categorized into three different lineages, lineage Ⅱ was the predominant types in food, and IIa was the main serogroups. CC8, CC101 and CC87 were the first three prevalent CCs among 23 detected CCs, accounting for 49.4%. Only 4.6% (11 isolates) of tested strains harbored antibiotic resistance genes, which were mostly trimethoprim genes (7 isolates, 2.9%). All strains were positive for LIPI-1, and only a part of strains harbored LIPI-3 and LIPI-4, accounting for 13.8% (33 isolates) and 14.2% (34 isolates), respectively. ST619 carried both LIPI-3 and LIPI-4. 51.5% (123 isolates) of strains carried SSI-1, and all CC121 strains harbored SSI-2. Different lineages, serogroups and CCs can be separated obviously through cgMLST analysis, and 24 sublineages were highly concordant with CCs. Conclusion: Ⅱa was the main serogroups in ready-to-eat food isolates in China; CC8, CC101 and CC87 were the prevalent CCs, and CC87 isolates was hypervirulent isolates, cgMLST method can be adopted for prospective foodborne disease surveillance and outbreaks detection.


Asunto(s)
Microbiología de Alimentos , Listeria monocytogenes/aislamiento & purificación , Listeriosis/microbiología , China/epidemiología , Humanos , Listeriosis/epidemiología
4.
FEMS Yeast Res ; 17(3)2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28449102

RESUMEN

Saccharomyces uvarum is a good wine yeast species that may have great potential for the future. However, sulfur tolerance of most S. uvarum strains is very poor. In addition there is still little information about the SSU1 gene of S. uvarum, which encodes a putative transporter conferring sulfite tolerance. In order to analyze the function of the SSU1 gene, two expression vectors that contained different SSU1 genes were constructed and transferred into a sulfite-tolerant S. uvarum strain, A9. Then sulfite tolerance, SO2 production, and PCR, sequencing, RT-qPCR and transcriptome analyses were used to access the function of the S. uvarum SSU1 gene. Our results illustrated that enhancing expression of the SSU1 gene can promote sulfite resistance in S. uvarum, and an insertion fragment ahead of the additional SSU1 gene, as seen in some alleles, could affect the expression of other genes and the sulfite tolerance level of S. uvarum. This is the first report on enhancing the expression of the SSU1 gene of S. uvarum.


Asunto(s)
Proteínas de Transporte de Anión/genética , Regulación Fúngica de la Expresión Génica , Saccharomyces/efectos de los fármacos , Sulfitos/farmacología , Transcriptoma , Alelos , Proteínas de Transporte de Anión/agonistas , Proteínas de Transporte de Anión/metabolismo , Tolerancia a Medicamentos/genética , Fermentación , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Anotación de Secuencia Molecular , Saccharomyces/genética , Saccharomyces/metabolismo , Dióxido de Azufre/metabolismo , Transformación Genética , Vino/análisis
5.
Nanoscale Res Lett ; 12(1): 18, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28058654

RESUMEN

The present study reports Bi5FeTi3O15 (BFTO) nanofibers/graphene (Gr) nanocomposites (BGr) as counter electrodes (CEs) in dye-sensitized solar cells (DSSCs). BFTO nanofibers with diameters of 40-100 nm were fabricated by sol-gel based electrospinning technique. The microstructure and surface morphology of the BFTO nanofibers and the BGr nanocomposites were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The electrochemical performances of BGr CEs were comprehensively characterized and investigated. Compared to pristine BFTO, the nanocomposites have a marked improvement in electrocatalytic performance for the reduction of triiodide because of larger surface area and lower transfer resistance on the electrolyte-electrode interface. The maximum power conversion efficiency has reached 9.56%, which is much larger than that of pure BFTO CEs (0.22%).

6.
Artículo en Chino | MEDLINE | ID: mdl-26898860

RESUMEN

OBJECTIVE: The objective of this study is to investigate the clinical manifestations of the superior semicircular canal dehiscence syndrome(SSCDS) and the treatment strategies. METHODS: Data from 20 cases diagnosed with SSCDS from September 2004 to December 2014 were retrospectively analyzed in this study. The clinical presentations including symptoms, signs, audiological and vestibular function examination, and their imaging characteristics and treatment strategies were reviewed. RESULTS: All of the patients demonstrated variable degree of vertigo. Four patients could not tolerate the environmental noise. Autophony was noted in nine cases, among whom, two patients could feel their eye movements and heart beat, one patient could feel his footstep, one patient couldn't endure the singing by himself. Slow component vertical tortional eye movement away from the effected eye were observed in twelve patients when loud noise was given or middle ear or intracranial pressure increased. Head movement was induced by loud noise in one case. Ten patients presented with low frequency hearing loss. One case was concomitance with chronic otitis media and demonstrated severe sensorineural hearing loss. Nine patients demonstrated normal hearing. Decreased thresholds were showed by VEMP examination in six cases. Variable bone defect overlying in the SSCDS was confirmed by CT scans in all of the cases. The surgical repair of the superior semicircular canal dehiscence was performed through the middle cranial fossa approach in three cases and mastoid approach in two cases. The dizziness and the autophony were significantly alleviated after surgery. CONCLUSIONS: The clinical manifestations of SSCDS mainly demonstrate dizziness, autophony and loss of low frequency hearing. Treatment strategies are mainly composed of avoidance of environmental noise and shouting voice of the patients themselves. Surgical repair of the superior semicircular canal dehiscence was proposed to conduct, either through the middle cranial fossa approach or mastoid approach, when the patient couldn't tolerate the sypmtoms.


Asunto(s)
Pérdida Auditiva Sensorineural/fisiopatología , Canales Semicirculares/fisiopatología , Fosa Craneal Media/cirugía , Mareo , Oído Medio/fisiopatología , Movimientos Oculares , Humanos , Apófisis Mastoides/cirugía , Estudios Retrospectivos , Canales Semicirculares/cirugía , Síndrome , Tomografía Computarizada por Rayos X , Vértigo
7.
Epidemiol Infect ; 144(6): 1345-54, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26542444

RESUMEN

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that was caused by a novel bunyavirus, SFTSV. The study aimed to disclose the epidemiological and clinical characteristics of SFTSV infection in China so far. An integrated clinical database comprising 1920 SFTS patients was constructed by combining first-hand clinical information collected from SFTS sentinel hospitals (n = 1159) and extracted data (n = 761) from published literature. The considered variables comprised clinical manifestations, routine laboratory tests of acute infection, hospitalization duration and disease outcome. SFTSV-IgG data from 19 119 healthy subjects were extracted from the published papers. The key clinical variables, case-fatality rate (CFR) and seroprevalence were estimated by meta-analysis. The most commonly seen clinical manifestations of SFTSV infection were fever, anorexia, myalgia, chill and lymphadenopathy. The major laboratory findings were elevated lactate dehydrogenase, aminotransferase, followed by thrombocytopenia, lymphocytopenia, elevated alanine transaminase and creatine kinase. A CFR of 12·2% was estimated, significantly higher than that obtained from national reporting data, but showing no geographical difference. In our paper, the mortality rate was about 1·9 parts per million. Older age and longer delay to hospitalization were significantly associated with fatal outcome. A pooled seroprevalence of 3·0% was obtained, which increased with age, while comparable for gender. This study represents a clinical characterization on the largest group of SFTS patients up to now. A higher than expected CFR was obtained. A wider spectrum of clinical index was suggested to be used to identify SFTSV infection, while the useful predictor for fatal outcome was found to be restricted.


Asunto(s)
Infecciones por Bunyaviridae/epidemiología , Enfermedades Transmisibles Emergentes/epidemiología , Fiebre/epidemiología , Phlebovirus/fisiología , Trombocitopenia/epidemiología , Adulto , Anciano , Infecciones Asintomáticas/epidemiología , Infecciones Asintomáticas/mortalidad , Infecciones por Bunyaviridae/mortalidad , Infecciones por Bunyaviridae/virología , China/epidemiología , Enfermedades Transmisibles Emergentes/mortalidad , Enfermedades Transmisibles Emergentes/virología , Femenino , Fiebre/virología , Hospitalización , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Seroepidemiológicos , Factores Socioeconómicos , Trombocitopenia/mortalidad , Trombocitopenia/virología
8.
Artículo en Chino | MEDLINE | ID: mdl-29871078

RESUMEN

The clinical manifestation was gradually hoarseness for half a year, with aggravation of dyspnea in three days. Physical examination and laryngoscopy showed laryngeal neoplasm, the glottis was not exposed, pedicle, no adhesion with the surrounding. CT scan showed glottic soft-tissue, density, unclear boundary. Enhanced CT showed anterior commissure thickening and tumor invasion of supraglottic region. Preoperative biopsy results: fibroblasts and fibrocyte were arranged in a crisscross pattern. Postoperative pathology showed laryngeal soft tissue sarcoma.


Asunto(s)
Neoplasias Laríngeas/diagnóstico , Sarcoma/diagnóstico , Glotis , Humanos , Laringoscopía , Laringe
9.
Genes Immun ; 16(6): 399-404, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26043172

RESUMEN

Among those developing tuberculosis (TB) after exposure to Mycobacterium tuberculosis, approximately 70% are males. Host genetic variation, particularly immune-related genes on the X chromosome, may contribute to sex-specific differences in TB incidences. To study whether X-linked gene variation is associated with sex-specific presentation of pulmonary TB (pTB), three single-nucleotide polymorphisms (SNPs) of the TLR8, CD40LG and IRAK1 genes on the X chromosome were genotyped in 923 patients and 1033 healthy individuals of the Han Chinese population. Frequencies of the variants were analyzed independently as well as in their combinations. CD40LG rs3092923 and its combined effects with the other two SNPs were associated with an increased risk of pTB only in males. In males, the rs3092923 genotype C/(-) conferred relative protection (odds ratio (OR): 0.52, 95% confidence interval (CI): 0.35-0.78, Pcorr.=0.0045) and the combined effects of three SNPs increased gradually as the number of risk alleles increased (OR: 2.58, 2.83 and 2.96 for one, two and three risk alleles, respectively). For the remaining SNPs, significance was obtained only for the AA genotype of IRAK1 rs3027898 in the combined and female-only analysis. Our results indicate a role of a CD40LG variant and its combined effects with distinct TLR8 and IRAK1 variants in susceptibility to pTB in males.


Asunto(s)
Ligando de CD40/genética , Ligando de CD40/inmunología , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/inmunología , Tuberculosis Pulmonar/genética , Tuberculosis Pulmonar/inmunología , Adulto , Pueblo Asiatico/genética , Estudios de Casos y Controles , China , Cromosomas Humanos X , Etnicidad , Femenino , Genes Ligados a X/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Quinasas Asociadas a Receptores de Interleucina-1/genética , Quinasas Asociadas a Receptores de Interleucina-1/inmunología , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Factores Sexuales , Receptor Toll-Like 8/genética , Receptor Toll-Like 8/inmunología , Tuberculosis Pulmonar/microbiología
10.
Clin Microbiol Infect ; 21(2): 204.e1-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25658566

RESUMEN

The wide epidemic and high case fatality rate have made severe fever with thrombocytopenia syndrome (SFTS) a significant public health problem. The diagnosis and discrimination of SFTS virus (SFTSV) infection at an early stage of the disease is important for treatment choice. A prospective study was performed in an SFTS reference hospital during 2011-2013. Suspected SFTS patients were recruited and prospectively observed. Comparison between SFTSV-positive and -negative patients was made to identify the parameters that were related to positive detection by discriminant and classification tree analysis. A total of 538 SFTSV-positive and 396 negative patients were recruited and observed. Multiple logistic regression models demonstrated the significant parameters associated with positive detection, including decreased platelet counts and elevated aspartate aminotransferase (AST) level during the first stage (1∼4 days), decreased white blood cell and platelet counts, elevated creatine kinase (CK) and AST levels during the second stage (5∼7 days), and older age, decreased consciousness and elevated CK and AST during the third stage (8-11 days). The classification trees disclosed that the significant predictors for positive SFTSV detection were AST >50.6 U/L and AST/alanine transaminase (ALT) >1.3 at the first stage, CK >257 U/L or 57.7 U/L < CK ≤98.5 U/L with AST/ALT >1.6 at the second stage, as well as CK >630.7 U/L or 114.3 U/L < CK ≤630.7 U/L with decreased consciousness at the third stage. In making the clinically probable diagnosis of SFTS, the supplementation of AST and CK evaluations might remarkably improve the diagnostic capacity of routine laboratory tests, while the leukopenia is of limited use.


Asunto(s)
Infecciones por Bunyaviridae/diagnóstico , Técnicas de Laboratorio Clínico/métodos , Phlebovirus/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Aspartato Aminotransferasas/sangre , Creatina Quinasa/sangre , Árboles de Decisión , Diagnóstico Diferencial , Femenino , Hospitales , Humanos , Leucopenia , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Estudios Prospectivos
11.
Nanoscale ; 7(10): 4406-10, 2015 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-25686156

RESUMEN

Optical effects in template-directed colloidal assembly are explored to fabricate microscale patterns with integrated three-dimensional (3D) nanostructures. This method allows the patterning of periodic nanostructures in arbitrarily designed regions by controlling particle assembly and light illumination. Using both "bottom-up" and "top-down" methods, this approach enables low-cost fabrication of hierarchical devices.

12.
Chem Sci ; 6(11): 6305-6311, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30090248

RESUMEN

Real time and non-invasive detection of pH in live biological systems is crucial for understanding the physiological role of acid-base homeostasis and for detecting pathological conditions associated with pH imbalance. One method to achieve in vivo pH monitoring is NMR. Conventional NMR methods, however, mainly utilize molecular sensors displaying pH-dependent chemical shift changes, which are vulnerable to multiple pH-independent factors. Here, we present a novel ratiometric strategy for sensitive and accurate pH sensing based on a small synthetic molecule, SPE1, which exhibits exceptionally slow proton exchange on the NMR time scale. Each protonation state of the sensor displays distinct NMR signals and the ratio of these signals affords precise pH values. In contrast to standard NMR methods, this ratiometric mechanism is not based on a chemical shift change, and SPE1 binds protons with high selectivity, resulting in accurate measurements. SPE1 was used to measure the pH in a single oocyte as well as in bacterial cultures, demonstrating the versatility of this method and establishing the foundation for broad biological applications.

13.
Eur J Clin Microbiol Infect Dis ; 34(1): 75-81, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25070494

RESUMEN

Human bocavirus (HBoV) is a novel parvovirus, often associated with respiratory tract diseases in children. This study explored the epidemiological characteristics and molecular evolution of HBoV-1 in southeastern China. Nasopharyngeal aspirates were collected from children admitted to hospital with acute respiratory tract infections. HBoV-1 was detected using real-time reverse transcription polymerase chain reaction and further characterized by complete genome sequences analysis. Among the 3,022 recruited children, 386 (12.77%) were HBoV-1-positive and 300 (77.72%) had co-detection with other respiratory viruses. Seasonal prevalence peaked in summer. HBoV-1 presence was significantly associated with asthma attack [odds ratio = 1.74; 95 % confidence interval: 1.30, 2.31; p < 0.001]. Similar results were obtained when either single detection or co-detection of HBoV-1 was considered, demonstrating the minor impact of co-detection on the clinical characteristics or epidemic pattern. Phylogenetic analysis based on the complete genome sequences showed that all the HBoV-1 sequences clustered together and no branch was formed that was supported by bootstrap value ≥ 750. The overall evolutionary rate of the complete genome of HBoV-1 was estimated at 1.08 × 10(-4) nucleotide substitutions per site per year (s/s/y) [95% highest probability density: (0.40-1.86) × 10(-4) s/s/y]. Selective pressure analysis showed that all the ω-values were less than 1, suggesting that HBoV-1 was under negative selective pressure. Site-by-site analysis identified the codon site 40 of the VP1 gene under positive selection. In conclusion, our study disclosed the epidemiological and genetic dynamics of HBoV-1 epidemics in southeastern China in the most recent 3 years, the information of which might help to further improve our understanding of HBoV-1 infection and guide better surveillance and control strategies in the future.


Asunto(s)
Epidemias , Bocavirus Humano/clasificación , Bocavirus Humano/aislamiento & purificación , Infecciones por Parvoviridae/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , Adolescente , Niño , Niño Hospitalizado , Preescolar , China/epidemiología , Análisis por Conglomerados , ADN Viral/genética , Evolución Molecular , Femenino , Genoma Viral , Genotipo , Bocavirus Humano/genética , Humanos , Lactante , Masculino , Epidemiología Molecular , Nasofaringe/virología , Infecciones por Parvoviridae/virología , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Infecciones del Sistema Respiratorio/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estaciones del Año , Análisis de Secuencia de ADN , Homología de Secuencia
14.
Cell Death Dis ; 4: e930, 2013 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-24263104

RESUMEN

In almost all vertebrates, the downstream of the sox9 signaling axis is well conserved for testis differentiation. The upstream genes of this pathway vary from species to species during evolution. Yet, little is known about how these signaling cascades are regulated and what cellular processes are dominant in ovary-testis transformation in juvenile zebrafish. In this study, we find that the transforming gonads undergo activation of sox9a-expressing stromal cells with increased deposition of extracellular matrix and formation of degenerative compartments. This leads to follicle disassembly, oocyte degeneration, follicle cell-cyp19a1a-amh conversions, and, eventually, formation of the testis cord. In vitro primary culture of juvenile ovary tissue in gonadotropins increases cytoplasmic accumulation of sox9a and p-Erk1/2, and induces mesenchymal morphology. MAPK inhibitors (MKI), a mixture of PD98059 and U0216, eliminate the cytoplasmic distribution but do not eradicate nuclear localization of sox9a and p-Erk1/2. Nuclear p53 are relatively increased in MKI-treated cells that exhibit less spreading and reduced proliferation. Despite uniform nuclear condensation, only a fraction of cells displayed the apoptotic phenotype. These results suggest that high levels of cytoplasmic sox9a and p-Erk1/2 activity activate stromal cells and enhance the production of extracellular matrix required for testis cord formation, whereas deregulation and translocation of sox9a and p-Erk1/2 induce follicle disassembly and incomplete apoptosis associated with nuclear p53. Together with the established FSH/cAMP/MAPK/AMH pathway in mammalian granulosa and Sertoli cells, we demonstrated that the sox9 axis signaling that determines testis formation in mammals also induces zebrafish ovary-testis transition, and adds to its conserved role in sex reversal.


Asunto(s)
Ovario/metabolismo , Factor de Transcripción SOX9/metabolismo , Testículo/metabolismo , Proteínas de Pez Cebra/metabolismo , Animales , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Femenino , Regulación del Desarrollo de la Expresión Génica , Inmunohistoquímica , Hibridación in Situ , Masculino , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Transcripción SOX9/genética , Transducción de Señal , Pez Cebra , Proteínas de Pez Cebra/genética
15.
J Biol Chem ; 276(27): 25005-13, 2001 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-11325968

RESUMEN

Translocation of conventional protein kinases C (PKCs) to the plasma membrane leads to their specific association with transmembrane-4 superfamily (TM4SF; tetraspanin) proteins (CD9, CD53, CD81, CD82, and CD151), as demonstrated by reciprocal co-immunoprecipitation and covalent cross-linking experiments. Although formation and maintenance of TM4SF-PKC complexes are not dependent on integrins, TM4SF proteins can act as linker molecules, recruiting PKC into proximity with specific integrins. Previous studies showed that the extracellular large loop of TM4SF proteins determines integrin associations. In contrast, specificity for PKC association probably resides within cytoplasmic tails or the first two transmembrane domains of TM4SF proteins, as seen from studies with chimeric CD9 molecules. Consistent with a TM4SF linker function, only those integrins (alpha(3)beta(1), alpha(6)beta(1), and a chimeric "X3TC5" alpha(3) mutant) that associated strongly with tetraspanins were found in association with PKC. We propose that PKC-TM4SF-integrin structures represent a novel type of signaling complex. The simultaneous binding of TM4SF proteins to the extracellular domains of the integrin alpha(3) subunit and to intracellular PKC helps to explain why the integrin alpha3 extracellular domain is needed for both intracellular PKC recruitment and PKC-dependent phosphorylation of the alpha(3) integrin cytoplasmic tail.


Asunto(s)
Antígenos CD/metabolismo , Integrina beta1/metabolismo , Glicoproteínas de Membrana , Proteínas de la Membrana , Proteína Quinasa C/metabolismo , Animales , Antígenos CD/química , Antígenos de Diferenciación de Linfocitos T/metabolismo , Western Blotting , Complejo CD3/metabolismo , Activación Enzimática , Técnica del Anticuerpo Fluorescente , Cabras , Humanos , Integrina alfa3 , Integrina alfa3beta1 , Integrina alfa6beta1 , Integrinas/química , Integrinas/metabolismo , Células Jurkat , Ratones , Conformación Proteica , Tetraspanina 24 , Tetraspanina 25 , Tetraspanina 28 , Tetraspanina 29 , Células Tumorales Cultivadas
16.
Mol Biol Cell ; 12(2): 351-65, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11179420

RESUMEN

Integrin alpha 3A cytoplasmic tail phosphorylation was mapped to amino acid S1042, as determined by mass spectrometry, and confirmed by mutagenesis. This residue occurs within a "QPSXXE" motif conserved in multiple alpha chains (alpha 3A, alpha 6A, alpha 7A), from multiple species. Phosphorylation of alpha 3A and alpha 6A did not appear to be directly mediated by protein kinase C (PKC) alpha, beta, gamma, delta, epsilon, zeta, or mu, or by any of several other known serine kinases, although PKC has an indirect role in promoting phosphorylation. A S1042A mutation did not affect alpha 3-Chinese hamster ovary (CHO) cell adhesion to laminin-5, but did alter 1) alpha 3-dependent tyrosine phosphorylation of focal adhesion kinase and paxillin (in the presence or absence of phorbol 12-myristate 13 acetate stimulation), and p130(CAS) (in the absence of phorbol 12-myristate 13 acetate stimulation), 2) the shape of cells spread on laminin-5, and 3) alpha 3-dependent random CHO cell migration on laminin-5. In addition, S1042A mutation altered the PKC-dependent, ligand-dependent subcellular distribution of alpha 3 and F-actin in CHO cells. Together, the results demonstrate clearly that alpha 3A phosphorylation is functionally relevant. In addition, the results strongly suggest that alpha 3 phosphorylation may regulate alpha 3 integrin interaction with the cytoskeleton.


Asunto(s)
Antígenos CD/metabolismo , Citoesqueleto/metabolismo , Integrinas/metabolismo , Transducción de Señal , Alcaloides , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Antígenos CD/genética , Benzofenantridinas , Células CHO , Moléculas de Adhesión Celular/metabolismo , Moléculas de Adhesión Celular/farmacología , Movimiento Celular , Secuencia Conservada , Cricetinae , Cricetulus , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Inhibidores Enzimáticos/farmacología , Genisteína/farmacología , Integrina alfa3 , Integrinas/genética , Espectrometría de Masas , Datos de Secuencia Molecular , Mutagénesis , Fenantridinas/farmacología , Fosforilación , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C/metabolismo , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/metabolismo , Serina/metabolismo , Estaurosporina/farmacología , Kalinina
17.
Artículo en Chino | MEDLINE | ID: mdl-11761859

RESUMEN

OBJECTIVE: To observe the effects of ANSON NANOTECH on the healing of cutaneous chronic wounds. METHODS: Thirty-four cases with 44 wounds were locally treated with ANSON NANOTECH in the wounds after debridement. Among them, there were 15 cases with traumatic ulcer (23 wounds), 9 cases with pressure ulcer(11 wounds), 5 cases with diabetes ulcer, and 5 cases with radiation ulcer. The healing time of wounds was used to evaluate the treatment results. RESULTS: The healing time in all of chronic wounds were accelerated. All wounds from trauma, diabetes and pressure were healed within 4 weeks and another 2 wounds from radiation injuries were healed over 4 weeks. The healing rate within 4 weeks was 95.5%. CONCLUSION: The results indicate that ANSON NANOTECH can accelerate the healing of chronic wounds. The mechanism probably include sterilization, improvement of local microcirculation, promotion of cell growth, and so on.


Asunto(s)
Antiinfecciosos Locales/uso terapéutico , Úlcera Cutánea/tratamiento farmacológico , Adolescente , Adulto , Anciano , Antiinfecciosos Locales/administración & dosificación , Enfermedad Crónica , Complicaciones de la Diabetes , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
Math Biosci ; 168(2): 201-10, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11121566

RESUMEN

In this paper, we establish a mathematical model of two species with stage structure and the relation of predator-prey, to obtain the necessary and sufficient condition for the permanence of two species and the extinction of one species or two species. We also obtain the optimal harvesting policy and the threshold of the harvesting for sustainable development.


Asunto(s)
Caimanes y Cocodrilos/fisiología , Conservación de los Recursos Naturales , Modelos Biológicos , Conducta Predatoria , Animales , China
19.
J Cell Sci ; 112 ( Pt 12): 1825-34, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10341202

RESUMEN

Rho family GTPases regulate diverse cellular processes, including extracellular signal-mediated actin cytoskeleton reorganization and cell growth. The functions of GTPases are positively regulated by guanine nucleotide exchange factors, which promote the exchange of GDP for GTP. Trio is a complex protein possessing two guanine nucleotide exchange factor domains, each with adjacent pleckstrin homology and SH3 domains, a protein serine/threonine kinase domain with an adjacent immunoglobulin-like domain and multiple spectrin-like domains. To assess the functional role of the two Trio guanine nucleotide exchange factor domains, NIH 3T3 cell lines stably expressing the individual guanine nucleotide exchange factor domains were established and characterized. Expression of the amino-terminal guanine nucleotide exchange factor domain results in prominent membrane ruffling, whereas cells expressing the carboxy-terminal guanine nucleotide exchange factor domain have lamellae that terminate in miniruffles. Moreover, cells expressing the amino-terminal guanine nucleotide exchange factor domain display more rapid cell spreading, haptotactic cell migration and anchorage-independent growth, suggesting that Trio regulates both cell motility and cell growth. Expression of full-length Trio in COS cells also alters actin cytoskeleton organization, as well as the distribution of focal contact sites. These findings support a role for Trio as a multifunctional protein that integrates and amplifies signals involved in coordinating actin remodeling, which is necessary for cell migration and growth.


Asunto(s)
Actinas/ultraestructura , Citoesqueleto/ultraestructura , Estructura Terciaria de Proteína , Proteínas/química , Células 3T3 , Animales , Células COS , Adhesión Celular/fisiología , División Celular/fisiología , Movimiento Celular/fisiología , Factores de Intercambio de Guanina Nucleótido , Ratones
20.
J Biol Chem ; 274(1): 11-9, 1999 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-9867804

RESUMEN

In a yeast two-hybrid screen, a protein named ICAP-1 (beta1 integrin cytoplasmic domain associated protein) associated with the integrin beta1 cytoplasmic tail but not with tails from three other integrin beta subunits (beta2, beta3, and beta5) or from seven different alpha subunits. Likewise in human cells, ICAP-1 associated specifically with the beta1 but not beta2, beta3, or beta5 tails. The carboxyl-terminal 14 amino acids of beta1 were critical for ICAP-1 interaction. ICAP-1 is a ubiquitously expressed protein of 27 and 31 kDa, with the smaller form being preferentially solubilized by Triton X-100. Phosphorylation of both 27- and 31-kDa forms was constitutive but was increased by 1.5-2-fold upon cell spreading on fibronectin, compared with poly-L-lysine. Also, ICAP-1 contributes to beta1 integrin-dependent migration because (i) ICAP-1 transfection markedly increased chemotactic migration of COS7 cells through fibronectin-coated but not vitronectin-coated porous filters, and (ii) support of beta1-dependent cell migration (in Chinese hamster ovary cells transfected with various wild type and mutant beta1 forms) correlated with ICAP-1 association. In summary, ICAP-1 (i) associates specifically with beta1 integrins, (ii) is phosphorylated upon beta1 integrin-mediated adhesion, and (iii) may regulate beta1-dependent cell migration.


Asunto(s)
Proteínas Portadoras/metabolismo , Citoplasma/metabolismo , Integrina beta1/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Proteínas de la Membrana , Proteínas Adaptadoras Transductoras de Señales , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas Portadoras/genética , Línea Celular , Movimiento Celular/fisiología , Clonación Molecular , Cricetinae , ADN Complementario , Humanos , Integrina beta1/química , Integrina beta1/fisiología , Datos de Secuencia Molecular , Fosforilación , Unión Proteica , Saccharomyces cerevisiae/genética
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