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1.
Artigo em Chinês | MEDLINE | ID: mdl-34365756

RESUMO

Objective: To study the effect of occupational exposure to non-steady state noise on hearing loss in the general equipment manufacturing industry, and to explore the feasibility of applying kurtosis index to evaluate hearing loss caused by non-steady state noise. Methods: A total of 233 workers exposed to non-steady state noise in 6 general equipment manufacturing enterprises were selected as the observation group, and 237 workers exposed to steady noise in 4 textile enterprises were selected as the control group between 2012 and 2018. Personal normalized continuous A-weighted sound pressure level equivalent to an 8 h-working-day (L(Aeq, 8 h)) was determined by a noise dosimeter. Cumulation noise exposure (CNE) was calculated from L(Aeq, 8 h) and related working age, and the CNE was adjusted by using noise kurtosis (CNE' after adjustment) . Meanwhile, questionnaires and hearing loss tests were performed for all subjects. The changes in the threshold of high-frequency hearing and the incidence of high-frequency hearing loss caused by noise in the two groups were compared before and after the adjustment of the kurtosis of CNE. The correlation between CNE and the incidence of high-frequency hearing loss before and after kurtosis adjustment was analyzed. Results: There was an difference between the 3000-8000 Hz hearing threshold of workers in different CNE groups (P<0.05) . logistic regression analysis showed that CNE was a risk factor of high-frequency hearing loss for workers in the observation group (OR=1.189, P<0.05) , and trend Chi-square test showed that the incidence of high-frequency hearing loss increased with CNE levels (χ(2)(trend)=34.415, P<0.05) .Before the kurtosis adjustment, in the CNE 95~<110 dB (A) ·year level group, the incidence of high-frequency hearing loss and the high-frequency hearing threshold in the observation group were significantly higher than those in the control group (P<0.05) . After kurtosis adjustment, there was no significant difference in the incidence of high-frequency hearing loss between the observation group and the control group in each level group (P>0.05) . The correlation between CNE after kurtosis adjustment and the incidence of high-frequency hearing loss was better than that before adjustment (after R(2) adjustment >before R(2) adjustment) . Conclusion: The effect of non-steady state noise on high-frequency hearing loss of workers in general equipment industry increases with the increase of CNE, and the effect of non-steady state noise on high-frequency hearing loss of workers is greater than that of steady noise. CNE' can be used to evaluate the hearing loss caused by non-steady state noise.


Assuntos
Perda Auditiva Provocada por Ruído , Ruído Ocupacional , Exposição Ocupacional , Perda Auditiva de Alta Frequência , Perda Auditiva Provocada por Ruído/epidemiologia , Humanos , Indústria Manufatureira , Ruído Ocupacional/efeitos adversos
2.
Artigo em Chinês | MEDLINE | ID: mdl-34365757

RESUMO

Objective: To analyse the dose-response relationships between the kurtosis metric of noise and noise-induced hearing loss (NIHL) and study the role of kurtosis in the evaluation of NIHL associated with non-Gaussian noise. Methods: From January 2012 to December 2017, a total of 1869 workers in seven manufacturing industries were selected as the study subjects. The basic data of the workers were investigated by questionnaire, personal noise waveform was collected for a long time, and pure tone hearing threshold was tested. The 8-hour continuous equivalent A sound level (L(Aeq, 8 h)) , cumulative noise exposure (CNE) and kurtosis structure indexes were calculated. The dose-response relationships between kurtosis and NIHL were analyzed by stratification analysis method, which controlled the influence of CNE, L(Aeq, 8 h), exposure duration, age and sex on hearing loss using high-frequency noise-induced permanent threshold shift (NIPTS(346)) and high-frequency noise-induced hearing loss (HFNIHL) as outcome indicators. Results: When CNE was <90 dB (A) ·year and ≥100 dB (A) ·year, NIPTS(346) in the extremely high kurtosis group was significantly greater than that in the Gaussian kurtosis, low kurtosis and medium kurtosis group (P<0.05) . In the workers exposed to L(Aeq, 8 h)<85 dB (A) and ≥94 dB (A) , NIPTS(346) in the extremely high kurtosis group was significantly greater than that in the Gaussian kurtosis group (P<0.05) . Among workers under the age of 50 or male workers, NIPTS(346) in the extremely high kurtosis group was significantly greater than that in the Gaussian kurtosis, low kurtosis and medium kurtosis group (P<0.05) . Kurtosis was positively correlated with NIPTS(346) (r=0.121, P<0.05) . When CNE was <100 dB (A) ·year, the detection rate of HFNIHL increased with the increase of kurtosis level (P<0.01) . Logistic regression analysis showed that kurtosis was an important influencing factor for HFNIHL (OR=1.321) . Conclusion: Kurtosis has a dose-response relationship with the detection rate of HFNIHL in noise exposed workers, and noise kurtosis is an influencing factor of NIHL.


Assuntos
Perda Auditiva Provocada por Ruído , Ruído Ocupacional , Exposição Ocupacional , Audição , Perda Auditiva Provocada por Ruído/etiologia , Humanos , Masculino , Indústria Manufatureira , Ruído Ocupacional/efeitos adversos , Exposição Ocupacional/efeitos adversos , Inquéritos e Questionários
3.
Artigo em Chinês | MEDLINE | ID: mdl-34365760

RESUMO

Objective: To investigate the occupational noise exposure characteristics and distribution of workers in wood furniture manufacturing industry and textile industry, so as to provide the basis for the establishment of noise source database and the prevention and control of noise hazards in China. Methods: In March 2020, a total of 653 workers in wood furniture manufacturing industry and textile industry were selected by cluster sampling method. A general questionnaire survey was conducted to measure the characteristics of noise exposure and analyze the changes of 8 h equivalent A-level (L(Aeq, 8 h)) and kurtosis of different industries and types of work. Results: The noise exposure L(Aeq, 8 h) of workers was (91.2±6.9) dB (A) , the median kurtosis and mean kurtosis were 37.0 and 105.0, respectively. 84.1% (549/653) of the workers had L(Aeq, 8 h)≥85 dB (A) , 49.0% (320/653) and 68.5% (447/653) of the workers had median kurtosis and mean kurtosis >10. The L(Aeq, 8 h) level of the textile industry was higher than that of the wooden furniture manufacturing industry, while the median and mean of kurtosis levels of the textile industry was lower than the wooden furniture manufacturing industry (P<0.01) . The L(Aeq, 8 h) levels of spinners and weavers were higher, and the median and mean of kurtosis of nailers were higher (P<0.05) . The mean and median of kurtosis were highly correlated among workers of two industries (r=0.80, P<0.01) . The L(Aeq, 8 h) was positively correlated with mean and median of kurtosis among workers of wooden furniture manufacturing industry (r=0.33 and 0.35, P<0.01) , while it was negatively correlated with mean and median of kurtosis among workers of textile industry (r=-0.45 and -0.40, P<0.01) . Conclusion: Indicators for noise exposure characteristics, such as L(Aeq, 8 h) and kurtosis vary greatly by industries and type of works. Multi-indicator joint measurement is conducive to comprehensive assessment of noise exposure and its health effects.


Assuntos
Ruído Ocupacional , Exposição Ocupacional , Humanos , Decoração de Interiores e Mobiliário , Indústria Manufatureira , Indústria Têxtil
4.
Artigo em Chinês | MEDLINE | ID: mdl-34365769

RESUMO

Objective: To investigate the distribution of noise exposure between non-steady state noise and steady-state noise for metal processing workers, which will provide scientific basis for the prevention and treatment of noise hazards in metal processing industry. Methods: The cross-section method was used to investigate the noise exposure of 737 workers from three metal processing industries in Zhejiang Province from October to December 2017. The general demographic information and occupational history were collected by questionnaire. The noise was recorded by individual noise meters, and the noise exposure intensity (equivalent continuous A-weighted noise exposure level normalized to an 8 h-working-day, L(Aeq, 8 h)) and kurtosis were calculated. Results: Workers exposed to noise in the metal processing industry were mainly 18-40 years old (527 workers, 71.51%) , men (570 workers, 77.34%) , and junior high school education background (416 workers, 56.45%) . There were 572 workers (77.61%) with noise exposure intensity (L(Aeq, 8 h)) greater than 85 dB (A) , 558 workers (75.71%) exposed to non-steady state noise (kurtosis ≥4) , and 634 workers (86.02%) with exposure duration less than 8 years. Among the 30 work types investigated, the work types with noise intensity reaching 100% were the stamping, welding and others from a children's car manufacturing factory in Ningbo, operating, chamfering, tapping, and thread rolling from an automobile parts manufacturing factory in Ningbo; The work types with a rate of 100% exposed to non-steady state noise were the grinding from a children's car manufacturing factory in Ningbo, assembling, assembly operating and others from an automobile brake manufacturing factory in Wenzhou, and polishing from an automobile parts manufacturing factory in Ningbo. Conclusion: Metal processing workers have a high rate of over-standard exposed to high noise intensity and a high proportion exposed to non-steady state noise. It is necessary to take sound insulation and noise reduction engineering control, and strengthen personal protection and occupational health management measures to prevent and control the noise hazards.


Assuntos
Perda Auditiva Provocada por Ruído , Ruído Ocupacional , Exposição Ocupacional , Adolescente , Adulto , Criança , Perda Auditiva Provocada por Ruído/epidemiologia , Perda Auditiva Provocada por Ruído/etiologia , Humanos , Masculino , Indústria Manufatureira , Inquéritos e Questionários , Adulto Jovem
5.
Artigo em Chinês | MEDLINE | ID: mdl-34365772

RESUMO

Non-steady state noise has become the main type of workplace noise. Compared with steady state noise, non-steady state noise may cause more serious hearing loss. This paper reviews the new situation of occupational hearing loss caused by non-steady state noise exposure, the overview of international noise exposure assessment standards and new challenges, and the new evidence of non-steady state noise induced hearing loss, so as to provide the basis for the future research of non-steady state noise induced hearing loss.


Assuntos
Perda Auditiva Provocada por Ruído , Ruído Ocupacional , Doenças Profissionais , Limiar Auditivo , Humanos , Ruído , Ruído Ocupacional/efeitos adversos , Doenças Profissionais/epidemiologia
6.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 36(10): 784-788, 2018 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-30541208

RESUMO

Objective: To assess the occupational health risk level of a small-scale furniture manufacturer, and to explore the applicability of the Singapore-developed semi-quantitative occupational risk assessment model for chemical exposure (Singapore model) in small-scale furniture manufacturers, and to provide a basis for the continuous occupational health management of manufacturers. Methods: A small-scale furniture manufacturer was selected as the study subject; an on-site occupational hygiene investigation was performed on the above manufacturer during April to June in 2017, and a risk assessment was carried out using the Singapore model. Results: The assessment results of the Singapore model indicated that risk levels of occupational exposure to harmful chemicals for the key positions in the workplace were inconsistent between the actual exposure level method and the exposure index method except for the following: high risk for formaldehyde exposure (risk level: 3.5 and 4.1, respectively) during woodworking process, high risk for dimethyl benzene exposure (risk level: 3.5 and 3.5, respectively) during burnishing process, medium risk for methyl benzene and dimethyl benzene exposure (risk level: 3.0 and 3.4, respectively) as well as for dimethyl benzene exposure (risk level: 3.0 and 3.3, respectively) during primer coating process, medium risk for methyl benzene exposure (risk level: 3.0 and 3.4, respectively) during gel painting process, and medium risk for cyclohexanone exposure (risk level: 2.8 and 2.8, respectively) during oil polishing process. The exposure index method yielded a higher risk level than the actual exposure level method, especially in the risk level of benzene exposure, which was rated as "high" and "very high" by the former but "low" by the latter. Conclusion: The Singapore model is suitable for risk assessment of occupational exposure to harmful chemicals in small-scale furniture manufacturers, which can provide a basis for further prevention and control measures taken by manufacturers.


Assuntos
Decoração de Interiores e Mobiliário , Indústria Manufatureira , Exposição Ocupacional/efeitos adversos , Humanos , Medição de Risco/métodos , Singapura
7.
Artigo em Chinês | MEDLINE | ID: mdl-29996249

RESUMO

Objective: To investigate the quality of life of the visual display terminal (VDT) operators in Hangzhou Internet enterprises and to analyze its influencing factors. Methods: Through cluster sampling,, 944 employees were investigated by demographic and general health questions and the MOS 36-Item Short Form Health Survey Questionnaire from October to November in 2016 and carried out statistical analysis. Results: VDT operators' physical functioning, role-physical, bodily pain, general health, vitality, social functioning, role-emotional, mental health, physical component summary and mental component summary scores were (86.3±17.0) , (82.5±30.3) , (80.6±16.1) , (56.8±18.6) , (53.7±15.6) , (78.5±17.8) , (81.2±31.9) , (48.8±19.3) , (51.1±8.9) , (43.8±9.1) . Except physical functioning, role-physical and physical component summary scores, the scores of other scales and mental component summary were lower than the norm (P<0.05) . Multivariable logistic regression showed that vegetable intake, sleeping and physical exercise had an impact on the physical component summary score. The influential factors of mental component summary score included marital status, education, neck pain and health concerns. Conclusion: We should pay attention to the quality of life of VDT operators in Internet enterprises, especially their mental health.


Assuntos
Nível de Saúde , Internet , Saúde Mental , Qualidade de Vida , Inquéritos Epidemiológicos , Humanos , Cervicalgia , Fatores Socioeconômicos , Inquéritos e Questionários
8.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 36(11): 834-836, 2018 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-30646647

RESUMO

Objective: To study the effects p-phenylenediamine (PPD) on lung function and health-related quality of life of occupational exposed workers. Methods: This study was based on data from a company that produce hair dye containing PPD in China. Workers who exposed to PPD were selected as the study group, and workers un-exposed to PPD were selected as the control group. Questionnaires on health-related quality of life of workers using the 36-item Short Form Health Survey (SF-36) . Occupational health examination assessment results were tested in Taizhou Cancer Hospital. The lung function test includes forced vital capacity (FVC) , forced expiratory volume in one second (FEV(1.0)) , and ratio of FEV(1.0) to FVC (FEV(1.0)/FVC) . Results: The difference in systolic blood pressure between the PPD exposed group and the control group was statistically significant (P<0.05) . FVC, FEV(1.0), and FEV(1.0)/FVC of the lung function indexes in the exposed group were lower than those in the control group (P<0.05) . In the health-related quality of life, body pain (P=0.002) , general health (P=0.029) , vitality (P=0.038) , and mental health (P=0.003) were lower in the exposed group than in the control group. Conclusion: Occupational exposed to PPD may induce hazard to the workers'lung function and may cause detrimental effect on workers' health-related quality of life.


Assuntos
Pulmão/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Fenilenodiaminas/toxicidade , Qualidade de Vida , Estudos de Casos e Controles , China , Volume Expiratório Forçado , Humanos , Pulmão/fisiopatologia , Capacidade Vital
9.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 36(12): 923-926, 2018 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-30812082

RESUMO

Objective: To study the effect of p-phenylenediamine (PPD) on liver and kidney function in occupational exposed workers. Methods: Workers in a hair dye production enterprise which used p-phenylenediamine as a raw material for production were selected as the main research population. Then we conducted a questionnaire survey on the basic conditions of workers and conducted occupational health checkups on general health status, liver and kidney function. Occupational health examination assessment results were tested in Taizhou Cancer Hospital. All data was built using EpiData 3.1 software, and statistical analysis was performed using software SPSS 20.0. Results: The liver function indicators including direct bilirubin, prealbumin, total protein, and white protein, globulin, aspartate aminotransferase, glutamyl transpeptidase, and total bilirubin in the workers exposed to high concentration of PPD were at high normal values, and these indicators were significantly different from low PPD concentration group (P<0.05) . The serum creatinine and serum uric acid in the renal function index were significantly higher in workers exposed to PPD than in workers exposed to low concentrations and in the control group (P<0.05) . Conclusion: Occupational exposed to PPD may have a hazard to the workers' liver and kidney function. Long-term occupational exposure to PPD may lead to increased cumulative exposure of workers, which may cause potential chronic liver and kidney damage in occupationally exposed populations.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Nefropatias/induzido quimicamente , Indústria Manufatureira , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Fenilenodiaminas/toxicidade , Tinturas para Cabelo , Humanos , Rim/efeitos dos fármacos , Rim/fisiopatologia , Fígado/efeitos dos fármacos , Fígado/fisiopatologia , Exposição Ocupacional/estatística & dados numéricos , Fatores de Tempo
10.
Dis Esophagus ; 30(1): 1-5, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27061221

RESUMO

The aims of this study were to investigate intrapapillary capillary loops (IPCLs) of superficial esophageal lesions changes in different types classified by the Japan Esophageal Society classification. The calibers, areas, and densities of IPCLs were detected in 34 cases of esophageal lesions using immunohistochemical analysis. Statistically significant differences in calibers, areas, and densities of IPCLs were observed between type A, type B1/B2, and type B3 area (P < 0.001). In conclusion, the results of this observation showed the Japan Esophageal Society classification of IPCL would help endoscopists to diagnose the type and the invasion depth of lesion in esophagus, and decide the treatment strategy.


Assuntos
Capilares/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Idoso , Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/cirurgia , Ressecção Endoscópica de Mucosa , Neoplasias Esofágicas/irrigação sanguínea , Neoplasias Esofágicas/cirurgia , Carcinoma de Células Escamosas do Esôfago , Esofagoscopia , Esôfago/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Imagem de Banda Estreita , Estudos Retrospectivos
11.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 34(10): 756-761, 2016 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-28043248

RESUMO

Objective: To explore the applicability of 2 different models of occupational health risk assessment in wooden furniture manufacturing industry. Methods: American EPA inhalation risk model and ICMM model of occupational health risk assessment were conducted to assess occupational health risk in a small wooden furniture enterprises, respectively. Results: There was poor protective measure and equipment of occupational disease in the plant. The concentration of wood dust in the air of two workshops was over occupational exposure limit (OEL) , and the CTWA was 8.9 mg/m3 and 3.6 mg/m3, respectively. According to EPA model, the workers who exposed to benzene in this plant had high risk (9.7×10-6 ~34.3×10-6) of leukemia, and who exposed to formaldehyde had high risk (11.4 × 10-6) of squamous cell carcinoma. There were inconsistent evaluation results using the ICMM tools of standard-based matrix and calculated risk rating. There were very high risks to be attacked by rhinocarcinoma of the workers who exposed to wood dust for the tool of calculated risk rating, while high risk for the tool of standard-based matrix. For the workers who exposed to noise, risk of noise-induced deafness was unacceptable and medium risk using two tools, respectively. Conclusion: Both EPA model and ICMM model can appropriately predict and assessthe occupational health risk in wooden furniture manufactory, ICMM due to the relatively simple operation, easy evaluation parameters, assessment of occupational- disease-inductive factors comprehensively, and more suitable for wooden furniture production enterprise.


Assuntos
Saúde do Trabalhador , Poluentes Ocupacionais do Ar , Poeira , Formaldeído , Humanos , Decoração de Interiores e Mobiliário , Indústria Manufatureira , Ruído , Doenças Profissionais , Exposição Ocupacional , Ocupações , Medição de Risco , Madeira
12.
J Am Mosq Control Assoc ; 7(1): 94-102, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1675261

RESUMO

The ability of 14 species of mosquitoes to biologically transmit Jamestown Canyon virus was tested. Four species not previously described as vectors of that virus transmitted to suckling mice. Among membrane-fed mosquitoes with disseminated infections, field-collected Aedes canadensis (1/3), Anopheles punctipennis (1/12), Coquillettidia perturbans (2/14) and a laboratory strain of Ae. epactius (19/67) transmitted virus. Two species were tested for their ability to transmit snowshoe hare virus: field-collected Ae. provocans (4/20) and Ae. abserratus-punctor (2/20) successfully transmitted to suckling mice. Evidence regarding the role of these species as field vectors is summarized.


Assuntos
Infecções por Bunyaviridae/transmissão , Culicidae/microbiologia , Encefalite da Califórnia/transmissão , Insetos Vetores/microbiologia , Aedes , Animais , Anopheles , Feminino , Intestinos/microbiologia , Camundongos , Especificidade da Espécie
13.
J Am Mosq Control Assoc ; 6(3): 461-8, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2230774

RESUMO

Twenty isolates of Jamestown Canyon virus were obtained from adult females of 5 Aedes species collected at the Houghton Lake Wildlife Research Area, Missaukee County, in north-central Michigan between 1985 and 1989. Fourteen were from Aedes provocans, and 6 were from 4 other snowmelt Aedes species. One isolate of trivittatus virus and one Cache Valley-like virus were also obtained. Seasonal succession patterns for numerous mosquito species were recorded over 4 years. The temporal association of adult mosquito emergence, virus isolations, and infection and seroconversion of sentinel deer suggest that Ae. provocans is a primary enzootic vector of Jamestown Canyon virus in that focus. We hypothesize that Ae. provocans provides an overwintering reservoir for Jamestown Canyon virus at the study site. A large dry ice-baited "tent trap" was the most productive method for collecting numerous aedine and other mosquito species.


Assuntos
Aedes/microbiologia , Vírus da Encefalite da Califórnia/isolamento & purificação , Animais , Cervos , Ecologia , Vírus da Encefalite da Califórnia/fisiologia , Feminino , Interações Hospedeiro-Parasita , Insetos Vetores , Michigan , Estações do Ano , Especificidade da Espécie , Tempo (Meteorologia)
14.
J Neurochem ; 55(2): 559-67, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2115073

RESUMO

We have cloned and characterized two variants of PC12 cells. MPT1 cells were selected by their resistance to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), and variant 2068 was isolated nonselectively as a large, flat-cell variant commonly occurring in PC12 cultures. Variant 2068 cells also exhibit resistance to MPTP. Karyotype analysis revealed that these variants are true derivatives of wild-type PC12 cells; however, each variant is tetraploid, whereas the wild-type parent is diploid. The two variants contain an altered level and composition of lactate dehydrogenase isoenzymes, which could account for a previously described difference in lactate metabolism. Both variants exhibit a partial loss of transformed phenotype in culture in that they are nonrefractile, grow in monolayers, and fail to multiply in soft agar. We suggest that this alteration in transformed phenotype may result in altered mitochondria and lactate dehydrogenase and thus account for their resistance to MPTP. Compared with wild-type PC12 cells, MPT1 cells have a decreased level of fos mRNA and an increased level of myc mRNA; the latter results from an increased level of transcription of exon 1 of the myc gene. Studies with hybrid cells obtained by fusing MPT1 cells with wild-type-like cells show that most, but not all, of the parameters of the MPT1 phenotype predominate.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Neoplasias das Glândulas Suprarrenais/patologia , Transformação Celular Neoplásica , Variação Genética , Feocromocitoma/patologia , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Animais , Resistência a Medicamentos , Expressão Gênica , Glicólise , Isoenzimas , Cariotipagem , L-Lactato Desidrogenase/metabolismo , Lactatos/metabolismo , Ácido Láctico , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Fenótipo , Feocromocitoma/genética , Feocromocitoma/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-fos , Proteínas Proto-Oncogênicas c-myc , Proto-Oncogenes , RNA Mensageiro/metabolismo , Ratos , Células Tumorais Cultivadas
15.
Cell Regul ; 1(7): 511-21, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2098114

RESUMO

We have identified and characterized a 5000-Da protein that induces neurite outgrowth from PC12 pheochromocytoma cells, enhances the survival of embryonic rat brain neurons in primary culture, and induces the multiplication of embryonic rat brain astrocytes in primary culture. The factor is produced by a flat cell PC12 variant that expresses the activated ras oncogene after transfection of the gene. The factor resembles transforming growth factor alpha (TGF alpha) and epidermal growth factor (EGF) in that it induces anchorage-independent colony formation of normal rat kidney cells in soft agar and competes with EGF for binding to the EGF receptor. Rat TGF alpha and human TGF alpha also induce neurite outgrowth from PC12 and enhance the survival of embryonic brain neurons. The PC12 variant-derived factor can be distinguished from TGF alpha and EGF immunologically and by migration rates on reversed-phase high-performance liquid chromatography.


Assuntos
Axônios/efeitos dos fármacos , Substâncias de Crescimento/farmacologia , Neurônios/efeitos dos fármacos , Fator de Crescimento Transformador alfa/farmacologia , Animais , Encéfalo/citologia , Encéfalo/embriologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia em Gel , Receptores ErbB/metabolismo , Genes ras , Substâncias de Crescimento/isolamento & purificação , Substâncias de Crescimento/metabolismo , Mitógenos , Neurônios/citologia , Testes de Precipitina , Ratos , Transfecção , Células Tumorais Cultivadas
16.
J Neurosci Res ; 26(2): 149-58, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2142222

RESUMO

Xylamine is an alkylating agent that is a substrate for and specific irreversible inhibitor of the cocaine-sensitive catecholamine transporter that functions in catecholamine reuptake into neurons and PC12 cells. [3H]xylamine prominently labels nine PC12 proteins; the relative xylamine-alkylation of a Mr 54,000 protein was decreased by cocaine and increased in the case of a PC12 variant, B9, which is deficient in catecholamine transport. [3H]xylamine labels no such protein in another transport variant, MPT1. We propose that this Mr 54,000 protein 1) is a component of the catecholamine transporter, 2) is present in B9 cells but in a conformation that reduces transporter activity and makes alkylation by xylamine more likely, and 3) is absent in MPT1 cells. Nerve growth factor treatment restores transporter activity in B9 cells but not in other transporter-deficient variants.


Assuntos
Proteínas de Transporte/metabolismo , Catecolaminas/farmacocinética , Cocaína/farmacologia , Indóis/metabolismo , Mazindol/metabolismo , Neurônios/metabolismo , Inibidores da Captação de Neurotransmissores/farmacologia , Compostos de Mostarda Nitrogenada/farmacologia , Alquilação , Animais , Proteínas de Transporte/efeitos dos fármacos , Linhagem Celular , Peso Molecular , Compostos de Mostarda Nitrogenada/metabolismo , Ratos
17.
J Am Mosq Control Assoc ; 5(3): 422-7, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2584976

RESUMO

A population of Aedes albopictus collected in 1986 in Harris County, Texas, was evaluated for its vector competence with 4 California serogroup viruses (Jamestown Canyon, Keystone, La Crosse and trivittatus). Rates of midgut infection, dissemination of virus beyond the midgut and oral transmission to suckling mice were markedly different for the 4 viruses in a pattern representative of the antigenic relationships known for the California serogroup. Only La Crosse virus was shown to be efficiently transmitted by this recently introduced mosquito population. The results suggest that populations of Ae. albopictus originating from the Harris County population might well be as efficient in transmitting La Crosse virus as are populations of the natural mosquito vector. Aedes triseriatus, from the midwestern La Crosse virus enzootic region. The public health implications of these results are discussed in relation to the rapid spread of Ae. albopictus throughout the eastern half of the United States and into regions where La Crosse virus is known to be enzootic.


Assuntos
Aedes/microbiologia , Bunyaviridae/fisiologia , Vírus da Encefalite da Califórnia/fisiologia , Encefalite por Arbovirus/transmissão , Encefalite da Califórnia/transmissão , Insetos Vetores/microbiologia , Animais , Animais Lactentes , Feminino , Camundongos , Camundongos Endogâmicos ICR , Texas , Células Vero
18.
J Neurochem ; 47(4): 1286-93, 1986 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3489073

RESUMO

We have isolated PC12 cell variants deficient in transporter-mediated uptake of 3,4-dihydroxyphenylethylamine (dopamine). The variants either were obtained nonselectively, or they were selected by resistance to guanethidine or N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Dopamine uptake into guanethidine-resistant cells occurred with a decreased Vmax; the Km for dopamine and inhibition by guanethidine were normal. MPTP-resistant cells lacked the capacity to take up dopamine. Most of the variants resembled wild-type PC12 in their response to nerve growth factor and the storage and secretion of dopamine. MPTP-resistant cells exhibited several deficiencies in addition to dopamine transport, i.e., no measurable storage of dopamine or acetylcholine and no observable response to nerve growth factor. Wild-type and variant cells were compared with respect to the labeling of cell proteins with [3H]xylamine, which binds covalently to certain proteins apparently only after entering PC12 via the catecholamine transporter. When intact variant cells were used, there was markedly reduced labeling of the proteins by [3H]xylamine. Almost all of these proteins were readily labeled when cell homogenates were exposed to [3H]xylamine. However, MPTP-resistant cells were missing three of these proteins. Northern blot analysis with cDNA clones revealed that the MPTP-resistant cells had markedly reduced levels of several specific mRNA species.


Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Membrana Transportadoras , Feocromocitoma/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Neoplasias das Glândulas Suprarrenais/genética , Animais , Transporte Biológico , Proteínas da Membrana Plasmática de Transporte de Catecolaminas , Linhagem Celular , Dopamina/metabolismo , Resistência a Medicamentos , Variação Genética , Guanetidina/farmacologia , Camundongos , Peso Molecular , Compostos de Mostarda Nitrogenada/metabolismo , Feocromocitoma/genética , Potássio/farmacologia , Proteínas/metabolismo , Piridinas/farmacologia , RNA Mensageiro/metabolismo , Ratos
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