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1.
Nat Commun ; 13(1): 2788, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35589709

RESUMO

Dog-mediated rabies kills tens of thousands of people each year in India, representing one third of the estimated global rabies burden. Whilst the World Health Organization (WHO), World Organization for Animal Health (OIE) and the Food and Agriculture Organization of the United Nations (FAO) have set a target for global dog-mediated human rabies elimination by 2030, examples of large-scale dog vaccination programs demonstrating elimination remain limited in Africa and Asia. We describe the development of a data-driven rabies elimination program from 2013 to 2019 in Goa State, India, culminating in human rabies elimination and a 92% reduction in monthly canine rabies cases. Smartphone technology enabled systematic spatial direction of remote teams to vaccinate over 95,000 dogs at 70% vaccination coverage, and rabies education teams to reach 150,000 children annually. An estimated 2249 disability-adjusted life years (DALYs) were averted over the program period at 526 USD per DALY, making the intervention 'very cost-effective' by WHO definitions. This One Health program demonstrates that human rabies elimination is achievable at the state level in India.


Assuntos
Doenças do Cão , Saúde Única , Raiva , Animais , Análise Custo-Benefício , Doenças do Cão/epidemiologia , Doenças do Cão/prevenção & controle , Cães , Humanos , Índia/epidemiologia , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/veterinária
2.
Nanotechnology ; 31(5): 055704, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31618710

RESUMO

The atomic layer deposition (ALD) of high-k dielectrics could build an efficient barrier against moisture and O2 adsorption. Such a barrier is highly needed for MoTe2 and WTe2 transition metal dichalcogenides because of the poor structural stability and the fast oxidization in ambient air. In situ x-ray photoelectron spectroscopy and ex situ atomic force microscopy and scanning transmission electron microscopy were employed to report a comparative study between the growth of Al2O3 on MoTe2 and WTe2 by means of traditional thermal ALD and plasma-enhanced ALD (PEALD). Similar to what has been observed on other 2D materials such as MoS2 and Graphene, the thermal ALD results in an islanding growth of Al2O3 on MoTe2 due to the dearth of dangling bonds, whereas, a uniform coverage of Al2O3 on WTe2 is observed and likely contributed to the high concentration of intrinsic structural defects. The PEALD behavior is consistent between MoTe2 and WTe2 providing a conformal and linear growth rate (∼0.08 nm/cycle), which correlates with the creation of Te-O and metal-O nucleation sites. However, a thin layer of interfacial Mo or W oxides gradually forms, resulting from the plasma-induced damage in the topmost (1-2) layers. Attempts to enhance the Al2O3/MoTe2 interfacial quality by physically evaporating an Al2O3 seed layer are investigated as well. However, the evaporated Al2O3 process causes thermal damage on MoTe2, necessitating a more 'gentle' ALD technique for the surface passivation.

3.
Epidemiol Infect ; 147: e247, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364582

RESUMO

Dogs harbor numerous zoonotic pathogens, many of which are controlled through vaccination programs. The delivery of these programs can be difficult where resources are limited. We developed a dynamic model to estimate vaccination coverage and cost-per-dog vaccinated. The model considers the main factors that affect vaccination programs: dog demographics, effectiveness of strategies, efficacy of interventions and cost. The model was evaluated on data from 18 vaccination programs representing eight countries. Sensitivity analysis was performed for dog confinement and vaccination strategies. The average difference between modelled vaccination coverage and field data was 3.8% (2.3%-5.3%). Central point vaccination was the most cost-effective vaccination strategy when >88% of the dog population was confined. More active methods of vaccination, such as door-to-door or capture-vaccinate-release, achieved higher vaccination coverage in free-roaming dog populations but were more costly. This open-access tool can aid in planning more efficient vaccination campaigns in countries with limited resources.


Assuntos
Vacinação em Massa/veterinária , Vacina Antirrábica/administração & dosagem , Raiva/prevenção & controle , Cobertura Vacinal/economia , Vacinação/estatística & dados numéricos , África Oriental , África do Norte , Animais , Ásia , América Central , Análise Custo-Benefício , Cães , Humanos , Vacinação em Massa/economia , América do Norte , Raiva/epidemiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Vacinação/economia
4.
Vaccine X ; 1: 100015, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-31384737

RESUMO

Rabies has profound public health, social and economic impacts on developing countries, with an estimated 59,000 annual human rabies deaths globally. Mass dog vaccination is effective at eliminating the disease but remains challenging to achieve in India due to the high proportion of roaming dogs that cannot be readily handled for parenteral vaccination. Two methods for the vaccination of dogs that could not be handled for injection were compared in Goa, India; the oral bait handout (OBH) method, where teams of two travelled by scooter offering dogs an empty oral bait construct, and the catch-vaccinate-release (CVR) method, where teams of seven travel by supply vehicle and use nets to catch dogs for parenteral vaccination. Both groups parenterally vaccinated any dogs that could be held for vaccination. The OBH method was more efficient on human resources, accessing 35 dogs per person per day, compared to 9 dogs per person per day through CVR. OBH accessed 80% of sighted dogs, compared to 63% by CVR teams, with OBH accessing a significantly higher proportion of inaccessible dogs in all land types. All staff reported that they believed OBH would be more successful in accessing dogs for vaccination. Fixed operational team cost of CVR was four times higher than OBH, at 127 USD per day, compared to 34 USD per day. Mean per dog vaccination cost of CVR was 2.53 USD, whilst OBH was 2.29 USD. Extrapolation to a two week India national campaign estimated that 1.1 million staff would be required using CVR, but 293,000 staff would be needed for OBH. OBH was operationally feasible, economical and effective at accessing the free roaming dog population. This study provides evidence for the continued expansion of research into the use of OBH as a supplementary activity to parenteral mass dog vaccination activities in India.

5.
Zoonoses Public Health ; 65(6): 662-668, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29726121

RESUMO

The highest rate of human rabies deaths reported in the Americas is in Haiti, and most of these deaths result from rabies virus infections that occur after individuals are bitten by infected dogs and do not receive rabies post-exposure prophylaxis. One barrier to rabies prevention in Haiti is a lack of knowledge about this disease among healthcare professionals and community members. During the past 4 years, The US Centers for Disease Control and Prevention has collaborated with public health officials and partners to develop, test and refine educational materials aimed at filling this need for rabies education. This report summarizes the use of feedback from knowledge, attitudes and practises surveys; key informant interviews; and focus groups to develop culturally appropriate rabies prevention materials for community members, health officials, clinicians, laboratory professionals, veterinary professionals, government officials and national and local district leaders about ways to prevent rabies. These formative research methods were critically important in ensuring that the materials would be culturally appropriate and would stand the greatest likelihood of motivating Haitians to protect themselves from rabies. Centers for Disease Control and Prevention is using lessons learned in Haiti to develop and test materials in other countries with high rates of canine rabies.


Assuntos
Doenças do Cão/virologia , Educação em Saúde/normas , Vacina Antirrábica/imunologia , Raiva/veterinária , Zoonoses , Animais , Mordeduras e Picadas , Doenças do Cão/epidemiologia , Doenças do Cão/prevenção & controle , Cães , Haiti/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Humanos , Saúde Pública , Raiva/mortalidade , Raiva/prevenção & controle
6.
Epidemiol Infect ; 145(8): 1624-1634, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28290915

RESUMO

Haiti has the highest human rabies burden in the Western Hemisphere. There is no published literature describing the public's perceptions of rabies in Haiti, information that is critical to developing effective interventions and government policies. We conducted a knowledge, attitudes and practices survey of 550 community members and 116 health professionals in Pétionville, Haiti in 2013 to understand the perception of rabies in these populations. The majority of respondents (85%) knew that dogs were the primary reservoir for rabies, yet only 1% were aware that bats and mongooses could transmit rabies. Animal bites were recognized as a mechanism of rabies transmission by 77% of the population and 76% were aware that the disease could be prevented by vaccination. Of 172 persons reporting a bite, only 37% sought medical treatment. The annual bite incidence rate in respondents was 0·9%. Only 31% of bite victims reported that they started the rabies vaccination series. Only 38% of respondents reported that their dog had been vaccinated against rabies. The majority of medical professionals recognized that dogs were the main reservoir for rabies (98%), but only 28% reported bats and 14% reported mongooses as posing a risk for rabies infection. Bites were reported as a mechanism of rabies transmission by 73% of respondents; exposure to saliva was reported by 20%. Thirty-four percent of medical professionals reported they would wash a bite wound with soap and water and 2·8% specifically mentioned rabies vaccination as a component of post-bite treatment. The majority of healthcare professionals recommended some form of rabies assessment for biting animals; 68·9% recommended a 14-day observation period, 60·4% recommended a veterinary consultation, and 13·2% recommended checking the vaccination status of the animal. Fewer than 15% of healthcare professionals had ever received training on rabies prevention and 77% did not know where to go to procure rabies vaccine for bite victims. Both study populations had a high level of knowledge about the primary reservoir for rabies and the mode of transmission. However, there is a need to improve the level of knowledge regarding the importance of seeking medical care for dog bites and additional training on rabies prevention for healthcare professionals. Distribution channels for rabies vaccines should be evaluated, as the majority of healthcare providers did not know where rabies vaccines could be obtained. Canine rabies vaccination is the primary intervention for rabies control programmes, yet most owned dogs in this population were not vaccinated.


Assuntos
Competência Clínica , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde/psicologia , Raiva/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Haiti , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Adulto Jovem
7.
Transbound Emerg Dis ; 64(5): 1433-1442, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27313170

RESUMO

An estimated 59 000 persons die annually of infection with the rabies virus worldwide, and dog bites are responsible for 95% of these deaths. Haiti has the highest rate of animal and human rabies in the Western Hemisphere. This study describes the status of animal welfare, animal vaccination, human bite treatment, and canine morbidity and mortality in Haiti in order to identify barriers to rabies prevention and control. An epidemiologic survey was used for data collection among dog owners during government-sponsored vaccination clinics at fourteen randomly selected sites from July 2014 to April 2015. A total of 2005 surveys were collected and data were analysed using parametric methods. Over 50% of owned dogs were allowed to roam freely, a factor associated with rabies transmission. More than 80% of dog owners reported experiencing barriers to accessing rabies vaccination for their dogs. Nearly one-third of the dog population evaluated in this study died in the year preceding the survey (32%) and 18% of these deaths were clinically consistent with rabies. Dog bites were commonly reported, with more than 3% of the study population bitten within the year preceding the survey. The incidence of canine rabies in Haiti is high and is exacerbated by low access to veterinary care, free-roaming dog populations and substandard animal welfare practices. Programmes to better understand the dog ecology and development of methods to improve access to vaccines are needed. Rabies deaths are at historical lows in the Western Hemisphere, but Haiti and the remaining canine rabies endemic countries still present a significant challenge to the goal of rabies elimination in the region.


Assuntos
Bem-Estar do Animal , Mordeduras e Picadas/epidemiologia , Mordeduras e Picadas/terapia , Doenças do Cão/prevenção & controle , Raiva/veterinária , Vacinação/estatística & dados numéricos , Animais , Mordeduras e Picadas/etiologia , Doenças do Cão/mortalidade , Cães , Haiti/epidemiologia , Humanos , Incidência , Morbidade , Raiva/mortalidade , Raiva/prevenção & controle , Vacina Antirrábica/uso terapêutico
8.
Zoonoses Public Health ; 64(2): 127-136, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27389926

RESUMO

Current guidelines in the setting of exposures to potentially rabid bats established by the Advisory Committee on Immunization Practices (ACIP) address post-exposure prophylaxis (PEP) administration in situations where a person may not be aware that a bite or direct contact has occurred and the bat is not available for diagnostic testing. These include instances when a bat is discovered in a room where a person awakens from sleep, is a child without an adult witness, has a mental disability or is intoxicated. The current ACIP guidelines, however, do not address PEP in the setting of multiple persons exposed to a bat or a bat colony, otherwise known as mass bat exposure (MBE) events. Due to a dearth of recommendations for response to these events, the reported reactions by public health agencies have varied widely. To address this perceived limitation, a survey of 45 state public health agencies was conducted to characterize prior experiences with MBE and practices to mitigate the public health risks. In general, most states (69% of the respondents) felt current ACIP guidelines were unclear in MBE scenarios. Thirty-three of the 45 states reported prior experience with MBE, receiving an average of 16.9 MBE calls per year and an investment of 106.7 person-hours annually on MBE investigations. PEP criteria, investigation methods and the experts recruited in MBE investigations varied between states. These dissimilarities could reflect differences in experience, scenario and resources. The lack of consistency in state responses to potential mass exposures to a highly fatal disease along with the large contingent of states dissatisfied with current ACIP guidance warrants the development of national guidelines in MBE settings.


Assuntos
Quirópteros , Raiva/veterinária , Animais , Humanos , Administração em Saúde Pública , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/transmissão , Vacina Antirrábica/efeitos adversos , Vacina Antirrábica/imunologia , Fatores de Risco , Estados Unidos/epidemiologia , Zoonoses
9.
Zoonoses Public Health ; 63(5): 396-402, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26542085

RESUMO

Taiwan had been considered rabies free since 1961. In 2013, Taiwan confirmed the detection of rabies virus in wild Taiwan ferret-badgers. Up to December 2014, there have been 423 rabies-confirmed ferret-badgers and three cases of spillover infection into non-reservoir hosts. Genetic analysis indicates that TFBV is distinct from all other known rabies virus variants. To date, ferret-badger rabies is known to occur only in China and Taiwan. The temporal dynamics of rabid ferret-badgers in Taiwan suggests that the epizootic appears to have subsided to enzootic levels as of December 2014. According to the current epidemiologic data, there is only one TFBV strain in Taiwan. TFBV is still sequestered to the mountainous regions. Humans are at risk mainly through exposure to the virus from infected domestic meso-carnivores, mainly dogs and cats. Dogs and cats should be vaccinated to establish an immunological barrier to stop the spread of the disease from mountainous regions to domestic meso-carnivores.


Assuntos
Reservatórios de Doenças/veterinária , Mustelidae/virologia , Administração em Saúde Pública , Vírus da Raiva/isolamento & purificação , Raiva/veterinária , Animais , Doenças do Gato/prevenção & controle , Gatos , Surtos de Doenças/veterinária , Doenças do Cão/prevenção & controle , Cães , Humanos , Vigilância da População , Prevalência , Raiva/epidemiologia , Raiva/prevenção & controle , Vacina Antirrábica/imunologia , Taiwan/epidemiologia
10.
Transpl Infect Dis ; 17(3): 389-95, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25851103

RESUMO

BACKGROUND: The rabies virus causes a fatal encephalitis and can be transmitted through organ transplantation. In 2013, a man developed rabies 18 months after receiving a kidney from a donor with rabies, who was not known to have been infected when the organs were procured. Three additional persons who received organs from the same donor (liver, kidney, heart), all of whom were not vaccinated for rabies before transplantation, received rabies post-exposure prophylaxis (PEP) with rabies immune globulin and 5 doses of rabies vaccine as soon as the diagnosis of rabies was made in the donor (18 months after their transplant surgeries). We describe their clinical management. METHODS: As the 3 recipients were all on immunosuppressive medications, post-vaccination serologic testing was performed using the rapid fluorescent focus inhibition test to measure rabies virus neutralizing antibodies (RVNAs). An acceptable antibody response to administration of rabies vaccine was defined as detection of RVNAs at a concentration ≥0.1 IU/mL from a serum specimen collected ≥7 days after the fifth vaccine dose. RESULTS: All 3 recipients demonstrated an acceptable antibody response despite their immunosuppressed states. More than 36 months have passed since their transplant surgeries, and all 3 recipients have no evidence of rabies. CONCLUSIONS: The survival of 3 previously unvaccinated recipients of solid organs from a donor with rabies is unexpected. Although the precise factors that led to their survival remain unclear, our data suggest that PEP can possibly enhance transplant safety in settings in which donors are retrospectively diagnosed with rabies.


Assuntos
Anticorpos Antivirais/sangue , Transplante de Coração/efeitos adversos , Transplante de Rim/efeitos adversos , Transplante de Fígado/efeitos adversos , Vacina Antirrábica/administração & dosagem , Vírus da Raiva/imunologia , Raiva/imunologia , Adulto , Humanos , Imunidade Humoral , Masculino , Pessoa de Meia-Idade , Profilaxia Pós-Exposição , Raiva/transmissão , Estudos Retrospectivos , Doadores de Tecidos , Resultado do Tratamento
11.
Zoonoses Public Health ; 61(8): 560-70, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24673934

RESUMO

This article describes and contrasts the public health response to two human rabies cases: one organ recipient diagnosed within days of symptom onset and the transplant donor who was diagnosed 18 months post-symptom onset. In response to an organ-transplant-related rabies case diagnosed in 2013, organ donor and recipient investigations were conducted by multiple public health agencies. Persons with potential exposure to infectious patient materials were assessed for rabies virus exposure. An exposure investigation was conducted to determine the source of the organ donor's infection. Over 100 persons from more than 20 agencies spent over 2700 h conducting contact investigations in healthcare, military and community settings. The 564 persons assessed include 417 healthcare workers [5.8% recommended for post-exposure prophylaxis (PEP)], 96 community contacts (15.6% recommended for PEP), 30 autopsy personnel (50% recommended for PEP), and 21 other persons (4.8% recommended for PEP). Donor contacts represented 188 assessed with 20.2% recommended for PEP, compared with 5.6% of 306 recipient contacts recommended for PEP. Human rabies cases result in substantial use of public health and medical resources, especially when diagnosis is delayed. Although rare, clinicians should consider rabies in cases of encephalitis of unexplained aetiology, particularly for cases that may result in organ donation.


Assuntos
Busca de Comunicante , Transplante de Órgãos/efeitos adversos , Saúde Pública , Vírus da Raiva/isolamento & purificação , Raiva/transmissão , Doadores de Tecidos , Infecção Hospitalar/virologia , Humanos , Profilaxia Pós-Exposição , Raiva/virologia , Medição de Risco
12.
J Clin Virol ; 57(2): 178-81, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23485347

RESUMO

Human rabies is rare in Western Europe. It is not easily recognized in the absence of a history of exposure. We describe the clinical course, diagnosis and follow-up of an imported human rabies case in Switzerland. The patient, a U.S. citizen, presented at an outpatient clinic in Iraq with pain in his right shoulder on July 5, 2012. On July 8 he was transferred to a hospital in the United Arab Emirates, where he exhibited progressive encephalitis with coma. On July 29, he was transferred to a hospital in Switzerland, where he died on July 31, 2012. The autopsy showed severe encephalitis. Rabies was diagnosed by the rapid fluorescent focus inhibition test (RFFIT) and confirmed by fluorescence antibody testing (FAT) in brain smears and immunohistochemistry on paraffin-embedded brain sections. The viral strain was characterized by RT-PCR followed by sequencing and phylogenetic analysis as an American bat rabies strain associated with Tadarida brasiliensis. Close contacts and exposed health care workers received postexposure prophylaxis (PEP).


Assuntos
Anticorpos Antivirais/sangue , Encéfalo/virologia , Vírus da Raiva/genética , Vírus da Raiva/isolamento & purificação , Raiva/diagnóstico , Adulto , Animais , Autopsia , Encéfalo/imunologia , Coma/complicações , Coma/diagnóstico , Encefalite Viral/complicações , Encefalite Viral/diagnóstico , Evolução Fatal , Humanos , Iraque , Masculino , Filogenia , Profilaxia Pós-Exposição , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/virologia , Vírus da Raiva/imunologia , Suíça , Emirados Árabes Unidos
13.
Br Med Bull ; 102: 17-42, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22586209

RESUMO

BACKGROUND: Unprecedented changes in both the scale and the complexity of international migration have led to international concern and controversy over the assessment of age in children and young people subject to immigration control or seeking asylum who say they are children yet have no documents to prove their stated age. SOURCES OF DATA: The article reviews the existing evidence on the reliability of medical and non-medical techniques for the assessment of chronological age. AREAS OF AGREEMENT: There is evidence that radiography (X-rays) of bones and teeth, which is increasingly relied upon by immigration authorities, is imprecise, unethical and potentially unlawful, and should not be used for age assessment. AREAS OF CONTROVERSY: Medical techniques including X-rays continue to be relied upon in the absence of an alternative approach resulting in legal challenges and uncertainty for children and young people. AREAS TIMELY FOR DEVELOPING RESEARCH: Further work is needed to establish a process for age assessment based on a 'holistic' multi-disciplinary approach which focuses not on chronological age exclusively but rather on the needs of children and young people subject to immigration control.


Assuntos
Determinação da Idade pelo Esqueleto/ética , Proteção da Criança/ética , Emigração e Imigração , Direitos Humanos , Determinação da Idade pelo Esqueleto/métodos , Determinação da Idade pelos Dentes/métodos , Fatores Etários , Antropometria/métodos , Temas Bioéticos , Criança , Proteção da Criança/estatística & dados numéricos , Europa (Continente) , Humanos , Refugiados
14.
Rev Sci Instrum ; 78(10): 104702, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17979444

RESUMO

The C-V electrical characterization of microstructures on a standard probe station is limited by the magnification of the imaging system and the precision of the probe manipulators. To overcome these limitations, we examine the combination of in situ electrical probing and a dual column scanning electron microscope/focused ion beam system. The imaging parameters and probing procedures are carefully chosen to reduce e-beam damage to the metal oxide semiconductor capacitor device under test. Estimation of shunt capacitance is critical when making femtofarad level measurements. C-V measurements of micron size metal-oxide-silicon capacitors are demonstrated.


Assuntos
Capacitância Elétrica , Análise de Falha de Equipamento/instrumentação , Metais/química , Microscopia Eletrônica de Varredura/instrumentação , Microscopia de Varredura por Sonda/instrumentação , Nanotecnologia/instrumentação , Transdutores , Impedância Elétrica , Eletrônica , Desenho de Equipamento , Análise de Falha de Equipamento/métodos , Microscopia Eletrônica de Varredura/métodos , Microscopia de Varredura por Sonda/métodos , Nanotecnologia/métodos , Óxidos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Langmuir ; 21(3): 950-5, 2005 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-15667173

RESUMO

The adsorption kinetics of octadecanethiol (ODT) and p-nitrobenzenethiol (NBT) from ethanol solutions has been studied by means of contact angle, optical ellipsometry, angle-resolved X-ray photoelectron spectroscopy (ARXPS), and grazing angle attenuated total reflection Fourier transform infrared (FTIR) measurements. ODT data were used as a reference for the kinetics studies of film growth. The growth of self-assembled monolayers from dilute solutions follows Langmuir isotherm adsorption kinetics. A saturated film is formed within 5 h after immersion in solutions of concentrations ranging from 0.0005 to 0.01 mM. The density of the monolayer depends on the concentration of the solution.

16.
Biochem J ; 310 ( Pt 2): 637-41, 1995 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-7654205

RESUMO

To explore the possibility that genes might compete for expression, we have studied transgenic mice producing high levels of the sheep milk protein, beta-lactoglobulin (BLG), in the mammary gland. Mice carrying one or more transgene loci expressed BLG in milk at levels ranging from 7 to 33 mg/ml. The effects of BLG synthesis on the levels of endogenous milk gene expression were examined. No significant increase in total milk protein concentration was recorded even in mice expressing the largest amounts of BLG. Measurement of individual milk proteins showed that transgene protein was manufactured at the expense of host protein synthesized in the gland. Whey acidic protein production was more suppressed than casein production. Suppression of endogenous proteins was matched by a reduction in the corresponding steady-state mRNA levels; in double-transgenic mice, which expressed the largest amounts of BLG, beta-casein and whey acidic protein mRNA populations were reduced to 75 and 56% of control levels respectively. We demonstrate that an exogenous gene competes effectively for expression with endogenous genes. Possible mechanisms of competition are discussed.


Assuntos
Lactoglobulinas/biossíntese , Glândulas Mamárias Animais/metabolismo , Proteínas do Leite/biossíntese , Animais , Eletroforese em Gel de Poliacrilamida , Feminino , Expressão Gênica , Cinética , Lactoglobulinas/genética , Camundongos , Camundongos Transgênicos , Leite/química , Proteínas do Leite/isolamento & purificação , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Ovinos
17.
Transgenic Res ; 4(1): 70-4, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7881464

RESUMO

The tissue-specific and developmental pattern of expression controlled by the proximal promoter (position-348 to +15) derived from the human alpha-1-antitrypsin (h alpha 1AT) gene was studied in transgenic mice. The short promoter segment was linked to the chloramphenicol acetyltransferase (CAT) reporter gene. The transgene showed highly specific expression in the liver and the correct developmental pattern of regulation. Interestingly, this short promoter targets expression to the liver with a greater specificity than that reported for larger alpha 1AT promoter fragments.


Assuntos
Regiões Promotoras Genéticas , alfa 1-Antitripsina/genética , Animais , Sequência de Bases , Células Cultivadas , Cloranfenicol O-Acetiltransferase/genética , Regulação da Expressão Gênica no Desenvolvimento , Ligação Genética , Células HeLa , Humanos , Fígado/metabolismo , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Cromossomo X
18.
Cell Mol Biol Res ; 41(1): 11-5, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7550448

RESUMO

The ovine beta-lactoglobulin gene is expressed abundantly in the mammary gland. This study determines whether the ovine beta-lactoglobulin promoter is sufficient for targeting tissue-specific expression in transgenic mice. To address this, the expression profile of an ovine beta-lactoglobulin promoter driven bacterial chloramphenicol acetyltransferase reporter construct was analysed. Comparison of the expression frequency of this hybrid transgene to that of a genomic beta-lactoglobulin transgene indicates that additional sequences, downstream of the promoter, are required for position-independent expression in transgenic mice. Nevertheless, the hybrid transgene was expressed specifically in the mammary gland. Furthermore, the hybrid transgene was expressed in the appropriate temporal pattern during pregnancy and lactation. Thus, the proximal promoter of the ovine beta-lactoglobulin gene contains sufficient sequence information to target expression to the mammary. This construct constitutes the basis for a compact mammary expression vector.


Assuntos
Regulação da Expressão Gênica , Lactoglobulinas/genética , Glândulas Mamárias Animais/metabolismo , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão/biossíntese , Animais , Cloranfenicol O-Acetiltransferase/metabolismo , Feminino , Lactação/metabolismo , Lactoglobulinas/biossíntese , Masculino , Glândulas Mamárias Animais/crescimento & desenvolvimento , Camundongos , Camundongos Transgênicos , Especificidade de Órgãos , Gravidez , Ovinos/genética , Fatores de Tempo
19.
Mol Cell Endocrinol ; 93(2): 157-65, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8349025

RESUMO

The alpha- and beta-subunits of the gonadotropin hormones are expressed in the gonadotrope cells of the anterior pituitary. There are no adequate in vitro systems for the analysis of beta-subunit gene expression. In this study, therefore, transgenic mice have been used to investigate the regulation of expression of the ovine luteinizing hormone beta-gene (oLH beta) in vivo. oLH beta was isolated, characterized, and 1.9 kb of the promoter fused to the bacterial reporter chloramphenicol acetyl-transferase (CAT). Three lines of transgenic mice were generated. CAT enzyme was detected in the pituitary of two lines, whereas the third line did not express. Measurement of endogenous luteinizing hormone and follicle stimulating hormone levels in both expressing lines revealed small differences when compared to controls, but these did not affect the fertility of the animals. Immunostaining of the anterior pituitary revealed that the oLH beta CAT transgene was expressed specifically in gonadotrope cells.


Assuntos
Regulação da Expressão Gênica , Hormônio Luteinizante/genética , Adeno-Hipófise/metabolismo , Regiões Promotoras Genéticas , Ovinos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , Cloranfenicol O-Acetiltransferase/biossíntese , Cloranfenicol O-Acetiltransferase/genética , Éxons , Feminino , Hormônio Foliculoestimulante/sangue , Genes Sintéticos , Humanos , Íntrons , Hormônio Luteinizante/biossíntese , Hormônio Luteinizante/sangue , Masculino , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Especificidade de Órgãos , Ratos , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Especificidade da Espécie
20.
Isr J Med Sci ; 25(2): 77-80, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2649452

RESUMO

Habituation is the progressive decrement of response with repeated stimulation. Neonatologists use this phenomenon to assess newborns for various pathological conditions of the CNS. The present study examined the time required for habituation of the startle response in 103 fetuses at various gestational ages (32 to 40 weeks). The external stimulus was produced by a door buzzer (80 to 90 db). Habituation time decreased as gestational age increased. About 85% of the fetuses showed habituation after less than 20 stimuli, and about 95% after less than 30 stimuli. In all cases habituation time never exceeded 50 stimuli.


Assuntos
Estimulação Acústica , Feto/fisiologia , Habituação Psicofisiológica , Feminino , Idade Gestacional , Humanos , Gravidez , Reflexo de Sobressalto , Fatores de Tempo , Ultrassonografia
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