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1.
J Dairy Sci ; 105(12): 10020-10032, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36270871

RESUMO

A large number of female goats are needed for the dairy goat industry; therefore, the development of a method to ensure the birth of more females than males in a single pregnancy will lead to economic benefits. Increasing the number of X-sperm would be an effective way to increase the proportion of female offspring. In this study, goat semen was incubated at pH 7.4 in alkaline diluent combined with resiquimod (R848) and the number of X-sperm was enriched by the swim-up method. The percentage of X-sperm was determined using the double TaqMan qPCR method. Sperm total motility, progressive motility, average path velocity, straight-line velocity, and curvilinear velocity were measured using a computer-aided sperm analysis system, and the functional parameters of the sperm plasma membrane, the acrosome, mitochondrial activity, ATP content, and reactive oxygen species levels were also measured. Lastly, the ratio of female embryos was determined by in vitro fertilization, and the number of female kids and the pregnancy rate of does was assessed by artificial insemination. The results showed that dilution of semen in an alkaline buffer containing R848 could enrich the number of X-sperm to 85.57% ± 3.27%. The progressive motility, average path velocity, straight-line velocity, curvilinear velocity, mitochondrial activity, and ATP level of the collected X-sperm-enriched semen were significantly reduced, but its total motility, plasma membrane, and acrosome were not affected. The in vitro fertilization experiments showed that the rate of female embryo production using X-sperm-rich seminal fluid could reach 83.25% (174/209), which was significantly higher than the proportion of female embryos in the control group, 47.71% ± 1.80% (104/218). As determined by artificial insemination, the number of female kids in the test group increased by 62.79% (243/387), which was significantly higher than that in the control group (47.65%, 193/405). There was no significant difference in pregnancy rate between the test group and the control group (71.71% vs. 78.48%). Therefore, this study demonstrated that use of a pH 7.4 diluent containing R848 is a simple and effective method of X-sperm enrichment for dairy goat production. Its application would allow does to produce more female offspring for herd expansion and milk production.


Assuntos
Preservação do Sêmen , Sêmen , Gravidez , Masculino , Feminino , Animais , Preservação do Sêmen/veterinária , Espermatozoides , Motilidade dos Espermatozoides , Cabras , Trifosfato de Adenosina
2.
Artigo em Chinês | MEDLINE | ID: mdl-36052585

RESUMO

Objective: To understand the current situation of emergency department nurses' work engagement, and analyze the relationship between emergency department nurses' organizational climate perception, work-related acceptance actions and work engagement. Methods: In May 2021, 273 emergency department nurses from 6 class Ⅲ class a general hospitals in Tianjin were selected as the research objects by using the convenient sampling method, and the general information questionnaire, work input scale, nurses' organizational climate perception scale and work-related acceptance action questionnaire were used for questionnaire survey. The correlation between job involvement and nurses' organizational climate perception and job-related acceptance action was analyzed by pearson correlation, and the influencing factors of job involvement were analyzed by multiple linear regression. Results: The average score of job involvement was (3.57±0.45) , the average score of nurses' organizational climate perception was (3.29±0.69) , and the score of work-related acceptance action was 35.00 (29.00, 47.00) . The results of correlation analysis showed that there was a positive correlation between nurses' organizational climate perception, job acceptance action and job involvement in emergency department (r=0.435, 0.518, P<0.05) . Multiple stepwise regression analysis showed that job acceptance, nurses' perception of organizational climate, health status, specialist nurses, education and emergency work years were the influencing factors of emergency department nurses' job involvement (P<0.05) , accounting for 41.9% of the total variation. Conclusion: We should create a good organizational atmosphere, improve the acceptance of emergency department nurses to nursing work, and improve the level of nurses' work input.


Assuntos
Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem Hospitalar , Serviço Hospitalar de Emergência , Humanos , Satisfação no Emprego , Percepção , Inquéritos e Questionários , Engajamento no Trabalho
3.
Clin Exp Obstet Gynecol ; 44(3): 487-488, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29949303

RESUMO

Ectopic pregnancy is defined as dislocation of a fertilized ovum anywhere other than in the cavity of uterus. Generally, the common site for dislocation is within fallopian tube, accounting for 95.5% of all ectopic gestations. Abdominal pregnancy is rare with a potentially life-threatening variation that resides within peritoneal cavity and the primary splenic pregnancy is even rarer. This report describes a patient with primary splenic pregnancy, who was successfully managed after splenectomy.


Assuntos
Gravidez Abdominal/diagnóstico , Gravidez Abdominal/cirurgia , Adulto , Tubas Uterinas , Feminino , Humanos , Gravidez , Esplenectomia
4.
Zhonghua Bing Li Xue Za Zhi ; 46(7): 481-484, 2017 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-28728222

RESUMO

Objective: To investigate the clinical value of p16/Ki-67 immunocytochemistry in patients with atypical squamous cells of undetermined significance(ASC-US). Methods: One hundred and seventy-one cases of thin-prep cytology test (TCT) diagnosed as ASC-US underwent p16/Ki-67 immunocytochemistry. All patients had colposcopy and biopsy from March 2015 to January 2016. Ninety of the 171 cases underwent high-risk HPV test at the same time. Results: p16/Ki-67 immunocytochemistry was positive in 43.9% (75/171) of the 171 cytology samples; the sensitivity and specificity of p16/Ki-67 immunocytochemistry were 77.6%(52/67) and 77.9%(81/104) in detecting CIN2+ , and the positive and negative predictive value were 69.3%(52/75) and 84.4%(81/96), respectively. The sensitivity and specificity in diagnosing CIN2+ were 100.0%(34/34) and 10.7%(6/56) for HPV test, and the positive and negative predictive value were 40.5%(34/84) and 6/6. p16/Ki-67 immunocytochemistry showed lower sensitivity but obviously higher specificity than high-risk HPV detection. Conclusion: p16/Ki-67 immunocytochemistry is a good triage test for identifying CIN2+ in ASC-US specimens.


Assuntos
Células Escamosas Atípicas do Colo do Útero/química , Inibidor p16 de Quinase Dependente de Ciclina/análise , Antígeno Ki-67/análise , Triagem , Biópsia , Colposcopia , Citodiagnóstico , Feminino , Humanos , Imuno-Histoquímica , Gravidez , Sensibilidade e Especificidade
5.
Zhonghua Bing Li Xue Za Zhi ; 46(8): 553-558, 2017 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-28810296

RESUMO

Objective: To evaluate the relationship between visceral pleural invasion (VPI) and other clinicopathological features in lung adenocarcinoma with tumor size ≤3 cm, and to investigate the impact of VPI on the patients' prognosis. Methods: The clinical and pathological features were retrospectively reviewed in 231 cases of lung adenocarcinoma with the largest diameter of tumor ≤3 cm, following complete resection and systemic lymphadenectomy. VPI was divided into three grades, PL0, PL1 and PL2 according to modified Hammar classification for lung cancer upon elastic fiber staining. Survival analysis was performed by Kaplan-Meier method, and the risk factors for prognosis were explored by Cox proportional hazards model. Patient prognosis was evaluated by progression-free survival (PFS) and overall survival (OS). Results: In all 231 cases, the number of patients with VPI was 70 (30.3%), of which 61 cases were PL1 and 9 cases were PL2. The remaining 161 cases (69.7%) had no VPI (PL0). The tumor size (P=0.003), histological grade (P<0.01), the presence of solid component (P=0.001) and micropapillary component (P=0.009), N stage (P<0.01) and TNM stage (P<0.01) were significantly correlated with VPI. Patients with VPI had significantly shorter PFS and OS than those without VPI (P<0.01). There were significant differences in PFS and OS between patients with different VPI levels (P<0.01). Cox multivariate regression analysis showed that VPI was not an independent prognostic factor, whereas PL2 was an independent prognostic factor for PFS (P=0.007), but not an independent prognostic factor for OS (P=0.052). Conclusions: For patients with lung adenocarcinoma of tumor size ≤3 cm, VPI is related to poor prognosis; However, only PL2 is an independent prognostic factor for PFS. It may be not necessary to separate PL0 and PL1 status in smaller lung adenocarcinomas. Therefore, the definition of VPI may need further modification through large cohort studies.


Assuntos
Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/patologia , Pleura/patologia , Adenocarcinoma de Pulmão/mortalidade , Tecido Elástico , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Excisão de Linfonodo , Análise Multivariada , Invasividade Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Prognóstico , Intervalo Livre de Progressão , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Coloração e Rotulagem , Carga Tumoral
6.
Artigo em Chinês | MEDLINE | ID: mdl-28780822

RESUMO

Objective: To investigate the current status of nurses' perceived professional benefits in 3A-level hospitals in Tianjin, and analyze its influencing factors. Methods: A total of 421 clinical nurses from five 3A-level hospitals in Tianjin were recruited for investigation on perceived professional benefits by Nurses'Perceived Professional Benefits Scale. Results: The total score of nurses' perceived professional benefit was 110.50±14.24, the score index was 77.34%. Among five dimensions, the highest scores index was 84.80% for personal development, the lowest was 71.57% for identification by relatives and friends. Multiple linear regression analysis showed the three variables, such as department, teaching and cooperative relation between doctors and nurses entered the model, higher perceived professional benefits was observed in medical nurses, teaching nurses, and those with better cooperative relation between doctors and nurses (P<0.05) . Conclusion: The investigated nurses in 3A-level hospitals in Tianjin show upper-moderate level of perceived professional benefits. Nursing managers should develop targeted interventions based on the factors affecting the perceived professional benefits of the nurses and further enhance their perceived professional benefits.


Assuntos
Atitude do Pessoal de Saúde , Recursos Humanos de Enfermagem Hospitalar/psicologia , China , Hospitais , Humanos , Inquéritos e Questionários
7.
Epidemiol Infect ; 142(2): 225-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23587429

RESUMO

A suspected dengue fever outbreak occurred in 2010 at a solitary construction site in Shenzhen city, China. To investigate this epidemic, we used serological, molecular biological, and bioinformatics techniques. Of nine serum samples from suspected patients, we detected seven positive for dengue virus (DENV) antibodies, eight for DENV-1 RNA, and three containing live viruses. The isolated virus, SZ1029 strain, was sequenced and confirmed as DENV-1, showing the highest E-gene homology to D1/Malaysia/36000/05 and SG(EHI)DED142808 strains recently reported in Southeast Asia. Further phylogenetic tree analysis confirmed their close relationship. At the epidemic site, we also detected 14 asymptomatic co-workers (out of 291) positive for DENV antibody, and DENV-1-positive mosquitoes. Thus, we concluded that DENV-1 caused the first local dengue fever outbreak in Shenzhen. Because no imported case was identified, the molecular fingerprints of the SZ1029 strain suggest this outbreak may be due to vertical transmission imported from Southeast Asia.


Assuntos
Vírus da Dengue/genética , Dengue/epidemiologia , Surtos de Doenças , Anticorpos Antivirais/imunologia , Sudeste Asiático/epidemiologia , Sequência de Bases/genética , China/epidemiologia , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/imunologia , Vírus da Dengue/isolamento & purificação , Humanos , Transmissão Vertical de Doenças Infecciosas , Filogenia
8.
Genet Mol Res ; 12(3): 3598-604, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-24085424

RESUMO

Spinal muscular atrophy (SMA) is one of the most common autosomal recessive diseases. Survival motor neuron1 (SMN1) is the SMA disease-determining gene. We examined the molecular basis of SMA in 113 Chinese SMA patients. Homozygous exon 7 and 8 deletions in SMN1 were detected by PCR-RFLP. Heterozygous deletion of SMN1 was analyzed based on variation of the sequencing peak height of the two different base pairs of exons 7 and 8 between SMN1 and SMN2. Subtle mutation was detected by genomic sequencing in the patients with heterozygous deletion of SMN1. In our study, the rate of deletion of SMN1 exon 7 and/or 8 was 91.2%; the rate of subtle mutations was 1.8%. We detected the same subtle mutation (p.Leu228X) of SMN exon 5 in two patients (one type I, one type III). The p.Ser8LysfsX23 and p.Leu228X mutations accounted for 13 of the 23 families with subtle mutations reported in the SMN1 gene of Chinese SMA. This is the first report where the phenotype of SMA-type III is associated with p.Leu228X. We found two subtle mutation hotspots (p.Ser8LysfsX23 and p.Leu228X) of SMN1 exons 1 and 5 in Chinese SMA patients. These two mutations have not been reported from America or Europe. It is proposed that the distribution of subtle mutations of SMN1 of SMA is associated with ethnicity or geographic origin.


Assuntos
Atrofia Muscular Espinal/genética , Mutação , Proteína 1 de Sobrevivência do Neurônio Motor/genética , China , Éxons , Feminino , Heterozigoto , Homozigoto , Humanos , Masculino , Atrofia Muscular Espinal/diagnóstico , Fenótipo , Reação em Cadeia da Polimerase , Deleção de Sequência
9.
Epidemiol Infect ; 140(5): 788-97, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21745428

RESUMO

The 2009 novel H1N1 influenza pandemic had a significant impact on Shenzhen's population with 2063 laboratory-confirmed human H1N1 cases and five deaths being reported. We used parameters from two population-based surveys and the Shenzhen Influenza Surveillance System to estimate the total number of H1N1 influenza infections in Shenzhen in the 2009 pandemic. The attack rate of influenza-like illness (ILI) in family households was 11·2% (95% CI 9·4-13·0), with 80·2% (95% CI 77·8-82·5) seeking medical care. The ILI attack rate in workers was 38·1% (95% CI 34·3-41·7) with 72·5% (95% CI 66·9-78·0) seeking medical care. The average H1N1 positive rate in individuals reporting ILI and testing by polymerase chain reaction was 22·7%. A total of 611 000-768 000 people, or 4·7-5·9% of the Shenzhen population, are estimated to have experienced H1N1 influenza. The estimated total number of cases of H1N1 is likely to be 330 times greater than the number of laboratory-confirmed cases.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Influenza Humana/mortalidade , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
10.
Genet Mol Res ; 11(4): 4130-7, 2012 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-23079993

RESUMO

Spondyloepiphyseal dysplasia (SED) is an autosomal dominant skeletal dysplasia characterized by short stature, abnormal epiphyses and flattened vertebral bodies. SED is mainly caused by mutations in the gene encoding the type II procollagen α-1 chain (COL2A1). We looked for mutations in COL2A1 in three unrelated Chinese families with SED. Putative mutations were confirmed by RFLP analysis. We identified three missense mutations (p.G504S, p.G801S and p.G1176V) located in the triple-helical domain; p.G801S and p.G1176V are novel mutations. The p.G504S mutation has been associated with diverse phenotypes in previous studies. Our study extends the mutation spectrum of SED and confirms a relationship between mutations in the COL2A1 gene and clinical findings of SED.


Assuntos
Colágeno Tipo II/genética , Mutação de Sentido Incorreto , Osteocondrodisplasias/genética , Povo Asiático , Sequência de Bases , Criança , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Humanos , Masculino , Osteocondrodisplasias/diagnóstico por imagem , Linhagem , Polimorfismo de Fragmento de Restrição , Radiografia
11.
Biomater Adv ; 133: 112625, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35523650

RESUMO

Beta-type titanium alloys are excellent candidates for biomedical applications because of their very low elastic modulus, excellent corrosion resistance, and biocompatibility. However, many traditional ß-type titanium alloys exhibit low yield strength. In this study, a small amount of Si (3 and 5 at.%) was added to a Ti-35Nb-7Zr-5Ta (wt%, TNZT) biomedical alloy prepared via laser powder bed fusion (LPBF) to increase its yield strength. The Si addition resulted in a significant increase in the compression yield strength of the alloy (from 802 to 1282 MPa). Meanwhile, the elastic moduli of the TNZT alloys (48.7-60.6 GPa) with 3 and 5 at.% Si were much lower than that of the Ti-6Al-4 V alloy (110 GPa), which is used extensively in clinical applications. The microstructural analyses indicated that the ultrahigh-strength of the TNZT alloy containing Si was due to the presence of ultrafine (Ti, Nb, Zr)5Si3 (S1) grains in the ß-Ti matrix. In addition, thin shell-shaped S1 and (Ti, Nb, Zr)2Si (S2) grains precipitated along the columnar ß-Ti grain boundaries in the TNZT alloys containing 3 and 5 at.% Si, respectively. Moreover, the introduction of Si to the TNZT alloy significantly refined the grains, weakened the cubic texture, decreased surface roughness, and improved Vickers hardness. The ultrahigh strength of the Si-containing TNZT alloys was due to grain boundary strengthening and precipitation strengthening. In addition, in vitro studies with MC3T3-E1 cells revealed that the cytocompatibilities of the LPBF-fabricated TNZT and Si-containing TNZT alloys were equivalent and were better than that of the LPBF-fabricated Ti-6Al-4 V alloy. In particular, the TNZT alloy with 3 at.% Si showed the best elastic modulus (48.7 ± 1.0 GPa), yield strength (1151 ± 17 MPa), and cell biological response among all the alloys investigated in this study, and hence was found to be a suitable candidate for application in load-bearing bone implants.


Assuntos
Ligas , Titânio , Ligas/química , Lasers , Pós , Silício , Titânio/química
12.
Epidemiol Infect ; 139(10): 1551-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21134322

RESUMO

Shenzhen is one of the largest migratory metropolitan cities in China. A standardized influenza surveillance system has been operating in Shenzhen for several years. The objectives of the present study were to describe the epidemiology of influenza in Shenzhen and to assess the impact of pandemic H1N1 on influenza activity. An average rate of 71 cases of influenza-like illness (ILI)/1000 consultations was reported, which was greater than the rate in the preceding 3 years. Laboratory surveillance showed that the annual proportion of specimens positive for influenza was 25·4% in 2009, representing a significant increase over the proportions of 5·4%, 11·6% and 12·2% in 2006, 2007 and 2008, respectively. A total of 414 ILI outbreaks were reported in 2009, which was a marked increase compared to the previous 3 years. Influenza activity reached a record high in Shenzhen in 2009. Seasonal A/H3N2 was the dominant strain during the summer and was gradually replaced by pandemic H1N1. A semi-annual cycle for influenza circulation began to appear due to the emergence of pandemic H1N1.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Surtos de Doenças , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estações do Ano , Adulto Jovem
13.
Genet Mol Res ; 10(2): 955-63, 2011 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-21644213

RESUMO

Pseudoachondroplasia is an autosomal dominant osteochondrodysplasia characterized by disproportionate short stature, joint laxity, and early onset osteoarthrosis. Pseudoachondroplasia is caused by mutations in the gene encoding cartilage oligomeric matrix protein (COMP). We looked for mutations in the COMP gene in three sporadic Chinese pseudoachondroplasia patients and identified two novel mutations, c.1189G>T (p.D397Y) and c.1220G>A (p.C407Y), and one recurrent mutation, c.1318G>C (p.G440R), in the calcium binding type III repeats of COMP. This study confirms the relationship between mutations of the COMP gene and clinical findings of pseudoachondroplasia; it also provides evidence for the importance of the calcium binding domains to the functioning of COMP.


Assuntos
Acondroplasia/metabolismo , Cálcio/metabolismo , Proteínas da Matriz Extracelular/genética , Glicoproteínas/genética , Mutação , Sequência de Bases , Proteína de Matriz Oligomérica de Cartilagem , Primers do DNA , Proteínas da Matriz Extracelular/metabolismo , Glicoproteínas/metabolismo , Humanos , Proteínas Matrilinas
15.
J Int Med Res ; 37(1): 264-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19215700

RESUMO

This study investigated the relationship between a cathepsin K (CTSK) gene mutation and the pathogenesis of pycnodysostosis in a Chinese patient. A typical pycnodysostosis case and 30 healthy controls were enrolled into the study. Genomic DNA was extracted from blood samples taken from the patient and controls, and the encoding exons of CTSK were amplified and sequenced. Sequencing of the CTSK gene revealed homozygosity for a novel missense mutation in the pycnodysostosis patient, predicting the amino acid exchange from glutamine to proline at position 187 (Q187P). This point mutation in exon 5 of the CTSK gene results in the typical clinical features found in Chinese patients with pycnodysostosis. No similar changes in the CTSK gene sequences were found in the healthy controls.


Assuntos
Povo Asiático/genética , Doenças Ósseas/enzimologia , Doenças Ósseas/genética , Catepsinas/genética , Mutação/genética , Sequência de Bases , Doenças Ósseas/diagnóstico por imagem , Estudos de Casos e Controles , Catepsina K , Catepsinas/metabolismo , Criança , Saúde , Humanos , Masculino , Radiografia
18.
J Mol Biol ; 242(1): 9-22, 1994 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-8078073

RESUMO

Region 2 of eubacterial sigma factors is highly conserved and the subdomain 2.4 is involved in -10 promoter recognition. An evolutionary conserved "RpoD box" has been identified at the junction of subdomain 2.3/2.4 in class I and class II sigma factors and there are two tryptophan residues at position 433 and 434 which can be used as intrinsic fluorescent markers to study their structure-function relationship. Site-directed mutagenesis of these two tryptophan residues has been carried out to generate three variants of sigma 70 of Escherichia coli RNA polymerase. These are W433F, W433G and W434G. sigma 70-W433F is found to be indistinguishable from the native sigma factor by both structural and functional analysis. sigma 70-W433G shows anomalous mobility on SDS-PAGE like the native sigma factor, is alpha-helical in conformation (50% helicity) although found to be less active in total transcription when reconstituted with core RNA polymerase. Free sigma 70-W434G, unlike the native sigma factor, shows the expected mobility of a 70 kDa protein on SDS-PAGE and has 20% helicity. Time-resolved fluorescence analysis indicates that free sigma 70-W434G has DNA binding ability, and displays a normal abortive initiation reaction but a decreased level of productive transcription after reconstitution with core RNA polymerase. A model is proposed in which tryptophan at position 434 interacts with the hydrophobic 1.1 domain of sigma 70 giving rise to the stability of the protein under denaturing conditions.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fator sigma/metabolismo , Transcrição Gênica , Sequência de Aminoácidos , Dicroísmo Circular , Proteínas de Ligação a DNA/química , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação Puntual , Fator sigma/química , Fator sigma/genética , Relação Estrutura-Atividade , Triptofano/química
19.
Mol Cell Endocrinol ; 112(2): 249-56, 1995 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-7489829

RESUMO

We have investigated the ability of a constitutively active Gq-alpha mutant, Q209L-alpha q, to regulate target gene expression. Transient expression in GH3 pituitary cells of a rat proximal prolactin promoter-chloramphenicol acetyltransferase construct (-187)PRL-CAT, was stimulated by co-expression of Q209L alpha q, but not by wild-type alpha q. Q209L-alpha q stimulated expression of constructs driven by promoters for either rat prolactin or growth hormone, but not of a control construct driven by the thymidine kinase promoter. Thus, transcriptional effects of alpha q are specific both for the activated state of this G-alpha subunit and the promoter examined. Since both the prolactin and growth hormone promoters are activated by the pituitary cell-specific transcription factor Pit-1, we examined whether a Pit-1 binding site could direct a response to Q209L-alpha q. Two copies of prolactin promoter Pit-1 binding site 1P conferred upon a heterologous metallothionein promoter a response to Q209L-alpha q, implying an involvement of this site in the transcriptional action of Q209L-alpha q on the prolactin promoter. The phorbol ester activator of protein kinase C, 12-O-tetradecanoylphorbol-13-acetate, stimulated (-187)PRL-CAT activity, but opposed the action of Q209L-alpha q on activity of this PRL-CAT construct. Q209L-alpha q stimulation of (-187)PRL-CAT activity was inhibited by co-expression of a dominant negative Raf mutant, Raf-C4, but not by a point mutant of Raf-C4 with reduced inhibitory properties. These results imply that activated alpha q subunits can stimulate prolactin promoter activity via a pathway that involves a Pit-1 DNA binding site(s), is opposed by protein kinase C, and is mediated by a pathway in which Raf-1 kinase plays a role.


Assuntos
Proteínas de Ligação ao GTP/fisiologia , Prolactina/genética , Regiões Promotoras Genéticas , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Linhagem Celular , Cloranfenicol O-Acetiltransferase/genética , Proteínas de Ligação ao GTP/genética , Hipófise/metabolismo , Plasmídeos , Proteína Quinase C/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-raf , RNA Mensageiro/metabolismo , Ratos , Receptores do Hormônio Liberador da Tireotropina/fisiologia , Proteínas Recombinantes de Fusão , Acetato de Tetradecanoilforbol/farmacologia , Hormônio Liberador de Tireotropina/farmacologia , Transfecção
20.
Org Lett ; 1(5): 757-9, 1999 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-16118879

RESUMO

[reaction: see text] A useful trans-substituted multifunctional cyclopentane with a chiral quaternary center was selectively synthesized by free radical Michael addition to the (Z)-propionate or -malonate derivatives. The stereoselectivity could be reversed by changing the configuration of the double bond.

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