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1.
Food Chem Toxicol ; 45(3): 419-30, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17070977

RESUMO

A 30-week dermal tumor promotion study was conducted to evaluate the dermal tumor-promoting potential of cigarette smoke condensate (CSC) collected from cigarettes containing flue-cured tobacco cured by a heat-exchange process (HE) relative to that of cigarettes containing flue-cured tobacco cured by the traditional direct-fire process (DF). Heat-exchange process cured tobacco contains significantly lower concentrations of tobacco specific nitrosamines (TSNAs) compared to traditional direct-fire cured tobacco. Mainstream CSCs were collected by cold trap from smoke generators using the Federal Trade Commission puffing regimen. Groups of 40 female SENCAR mice were initiated by a single application of 75 micro g 7,12-dimethylbenz[a]anthracene (DMBA) to the shaved dorsal skin. CSCs were then applied to the skin three times/week for 29 weeks at 9, 18, or 36mg tar/application. End-points included body weights, clinical observations, organ weights, dermal tumor development and histopathology. The numbers of dermal tumors and the numbers of tumor-bearing mice for each CSC were statistically different from the DMBA/acetone control group and increased with increasing dose. When corresponding doses of each CSC were compared, only the DMBA/mid-dose HE CSC group was statistically significantly different (lower) from the corresponding DMBA/mid-dose DF CSC group. In this assay, the dermal tumor-promotion potential of CSC from heat-exchange flue-cured tobacco did not differ from that of traditional direct-fire flue-cured tobacco CSC.


Assuntos
Carcinógenos/toxicidade , Nicotiana/química , Nitrosaminas/toxicidade , Pele/efeitos dos fármacos , Alcatrões/toxicidade , Administração Cutânea , Animais , Carcinógenos/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Camundongos , Camundongos Endogâmicos SENCAR , Nitrosaminas/administração & dosagem , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/patologia
2.
Food Chem Toxicol ; 42(5): 851-63, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15046832

RESUMO

Numerous chemical and toxicological studies indicate that smoke from ECLIPSE, a cigarette that primarily heats rather than burns tobacco, is simplified and reduced in specific chemicals believed to be associated with smoking-related diseases, and demonstrates reduced smoke toxicity and biological activity in vitro when compared to conventional tobacco burning cigarettes. These data led to the hypothesis that cigarette smoke condensate (CSC) from ECLIPSE should have lower tumorigenicity than 1R4F condensate in the SENCAR mouse dermal tumor promotion assay. Female SENCAR mice were initiated with a single topical application of 7,12-dimethylbenz[a]anthracene (DMBA) followed by promotion with ECLIPSE or 1R4F CSC. Dermal application of 10, 20, or 40 mg ECLIPSE or 1R4F CSC three times/week for 29 weeks did not alter body weights, survival or other indicators of subchronic toxicity. In DMBA-initiated mice, there were significant increases in both the number of microscopically confirmed tumor-bearing animals and total number of microscopically confirmed dermal tumors at all 1R4F CSC doses and the high-dose ECLIPSE CSC. However, the number of ECLIPSE tumor-bearing animals were reduced 83%, 93% and 67% at the low-, mid- and high-doses, respectively, compared to the 1R4F. Similarly, the total number of dermal tumors was reduced 91%, 94% and 87% at the low-, mid- and high-dose, respectively, compared to the 1R4F CSC. ECLIPSE CSC demonstrated dramatic reductions in dermal tumor promotion potential compared to 1R4F CSC.


Assuntos
Mutagênicos/efeitos adversos , Nicotiana/efeitos adversos , Neoplasias Cutâneas/induzido quimicamente , Pele/efeitos dos fármacos , Fumaça/efeitos adversos , 9,10-Dimetil-1,2-benzantraceno/administração & dosagem , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Administração Tópica , Animais , Bioensaio , Carcinógenos/administração & dosagem , Carcinógenos/toxicidade , Relação Dose-Resposta a Droga , Feminino , Temperatura Alta , Humanos , Camundongos , Camundongos Endogâmicos SENCAR , Testes de Mutagenicidade , Mutagênicos/administração & dosagem , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia
3.
Regul Toxicol Pharmacol ; 39(2): 135-49, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15041145

RESUMO

The mouse dermal initiation/promotion bioassay has been used for several decades to study cigarette smoke condensates (CSCs). However, these studies have used highly variable methodologies that differ in the manner of CSC collection, duration of treatment, mouse strain, number of mice and endpoints measured. In this report, a protocol that uses female SENCAR mice and standardizes many of the procedures is presented. A reference cigarette (University of Kentucky 1R4F), readily available to researchers, was used. This report presents the combined data from four independent studies. Female, SENCAR mice (40/group) were treated with a single dose (75microg) of dimethylbenz[a]anthracene (DMBA) as an initiator, followed 1 week later by treatment (three times/week) with 10, 20 or 40mg "tar"/application of 1R4F CSC for 29 weeks. There were no treatment-related effects on body weights. Histological diagnosis of all masses at study termination indicated a dose-dependent increase in the number of tumor-bearing mice and total tumor number. These studies support the conclusion that the 1R4F cigarette is suitable for use as a reference standard and the protocol presented is an appropriate and standardized model suitable for the comparative evaluation of CSC.


Assuntos
Nicotiana/química , Nicotiana/toxicidade , Neoplasias Cutâneas/induzido quimicamente , Fumaça/efeitos adversos , Fumaça/análise , 9,10-Dimetil-1,2-benzantraceno/administração & dosagem , 9,10-Dimetil-1,2-benzantraceno/toxicidade , Acetona/efeitos adversos , Animais , Peso Corporal/efeitos dos fármacos , Carcinógenos/administração & dosagem , Carcinógenos/toxicidade , Relação Dose-Resposta a Droga , Feminino , Camundongos , Camundongos Endogâmicos SENCAR , Padrões de Referência , Pele/efeitos dos fármacos , Pele/patologia , Neoplasias Cutâneas/patologia , Análise de Sobrevida
4.
J Virol ; 75(23): 11474-82, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11689629

RESUMO

The effectiveness of vaccination programs would be enhanced greatly through the availability of vaccines that can be administered simply and, preferably, painlessly without the need for timed booster injections. Tetanus is a prime example of a disease that is readily preventable by vaccination but remains a major threat to public health due to the problems associated with administration of the present vaccine. Here we show that a protective immune response against live Clostridium tetani infection in mice can be elicited by an adenovirus vector encoding the tetanus toxin C fragment when administered as a nasal or epicutaneous vaccine. The results suggest that these vaccination modalities would be effective needle-free alternatives. This is the first demonstration that absorption of a small number of vectored vaccines into the skin following topical application of a patch can provide protection against live bacteria in a disease setting.


Assuntos
Adenoviridae/genética , Vacinas Bacterianas/administração & dosagem , Vetores Genéticos , Tétano/prevenção & controle , Administração Cutânea , Administração Intranasal , Anticorpos Antibacterianos/biossíntese , Vacinas Bacterianas/imunologia , Sequência de Bases , Clostridium tetani/imunologia , Primers do DNA , Reação em Cadeia da Polimerase
6.
Vet Clin North Am Small Anim Pract ; 31(3): 535-8, vii, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11446102

RESUMO

Recombinant technology is relatively new to veterinary medicine. It combines safety, purity, potency, and efficacy in the vaccine. Its positive features include not exposing the vaccinate to the pathogen, the lack of need for adjuvants, and stability that allows some vaccine to remain viable at ambient temperatures. These recombinants can receive multiple genetic inserts and present an opportunity to have multiple combination vaccines for use in animals. Licensed recombinant vaccines in veterinary medicine include those protecting against Lyme disease, pseudorabies, rabies, canine distemper, Newcastle disease, and a strain of avian influenza.


Assuntos
Doenças dos Animais/prevenção & controle , Vacinas Sintéticas , Animais , Medicina Veterinária/tendências
7.
Semin Vet Med Surg Small Anim ; 12(3): 186-92, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9283244

RESUMO

Immunomodulation is now possible in veterinary medicine with the licensure of a number of biological products by the United States Department of Agriculture for veterinary use. These products activate primarily macrophages, induce the production of cytokines, and have various effects on the activity and proliferation of B and T lymphocytes. Those products most commonly used are inactivated whole bacteria of Propionibacterium acnes, cell wall fractions of nonpathogenic Mycobacterium spp, and the lysate derived from lysis of Staphylococcus aureus by a bacterial phage. All products have been licensed for use against specific diseases, but the literature includes studies for off-label usage. These immunomodulators are considered to be nonspecific stimulators of the immune system and may affect both humoral and cellular functions of immunity.


Assuntos
Doenças do Gato/terapia , Citocinas/biossíntese , Doenças do Cão/terapia , Doenças dos Cavalos/terapia , Imunoterapia/veterinária , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/uso terapêutico , Animais , Doenças do Gato/imunologia , Gatos , Citocinas/fisiologia , Doenças do Cão/imunologia , Cães , Doenças dos Cavalos/imunologia , Cavalos , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/metabolismo , Imunoterapia/métodos , Pioderma/imunologia , Pioderma/terapia , Pioderma/veterinária , Doenças Respiratórias/imunologia , Doenças Respiratórias/terapia , Doenças Respiratórias/veterinária
9.
J Natl Cancer Inst ; 70(4): 771-6, 1983 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6572763

RESUMO

Individual Hereford cows bearing benign precursor lesions of ocular squamous cell carcinoma were treated by intralesional injection of mycobacterial cell walls in an oil-in-water emulsion in an attempt to interrupt neoplastic progression. Thirty-one months after treatment, statistical analysis of data indicated that intralesional BCG cell wall vaccine can interrupt this process and provides effective immunoprophylactic prevention of malignant disease.


Assuntos
Vacina BCG/uso terapêutico , Doenças dos Bovinos/terapia , Neoplasias Oculares/veterinária , Imunoterapia , Animais , Bovinos , Doenças dos Bovinos/cirurgia , Neoplasias Oculares/cirurgia , Neoplasias Oculares/terapia , Feminino , Seguimentos
10.
Am J Vet Res ; 44(2): 254-9, 1983 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6830014

RESUMO

In field observations of young cattle grazing on certain high-altitude ranges infested with the locoweed Oxytropis sericea, a high frequency of clinical congestive right ventricular failure was identified. At necropsy of affected calves, there were right ventricular hypertrophy and dilation, subcutaneous edema, hydrothorax, diarrhea, and chronic passive congestion of liver. Microscopically, there was neurovisceral foamy cytoplasmic vacuolation, characteristic of locoism. An experiment was set up to test the relationship of O sericea to congestive right-ventricular failure. Preliminary investigation supports the field observation.


Assuntos
Doenças dos Bovinos/etiologia , Insuficiência Cardíaca/veterinária , Intoxicação por Plantas/veterinária , Plantas Tóxicas , Altitude , Animais , Bovinos , Doenças dos Bovinos/patologia , Feminino , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/patologia , Miocárdio/patologia , Intoxicação por Plantas/etiologia , Intoxicação por Plantas/patologia
12.
Experientia ; 36(10): 1239-40, 1980 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-7418819

RESUMO

A simple method for the anchorage-dependent culture of line 10 guinea-pig hepatoma cells is described.


Assuntos
Neoplasias Hepáticas Experimentais/fisiopatologia , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Fibronectinas/farmacologia , Cobaias
13.
Am J Vet Res ; 41(3): 377-82, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7369611

RESUMO

Various species of nitro-containing Astragalus, and the toxic principle of these plants, 3-nitropropionic acid or 3-nitro-1-propanol, were fed to sheep and cattle at doses which produced chronic or acute intoxication. The signs of intoxication produced were similar to those observed in poisoning that occurs under field conditions. The signs of intoxication were emphysema and difficulty in locomotion. Primary microscopic lesions were observed in the lungs and CNS. The lungs had varying degrees of alveolar emphysema and there were varying degrees of wallerian degeneration of the spinal cord.


Assuntos
Doenças dos Bovinos/patologia , Intoxicação por Plantas/veterinária , Propanóis , Propionatos/intoxicação , Doenças dos Ovinos/patologia , 1-Propanol/intoxicação , Animais , Encéfalo/patologia , Bovinos , Doenças dos Bovinos/induzido quimicamente , Rim/patologia , Pulmão/patologia , Nitrocompostos , Intoxicação por Plantas/patologia , Ovinos , Doenças dos Ovinos/induzido quimicamente , Medula Espinal/patologia
14.
Am J Vet Res ; 37(7): 845-50, 1976 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-937807

RESUMO

Rats fed pellets containing locoweed developed typical microscopic lesions of locoweed poisoning. Rats fed a water extract of locoweed or urine from sheep given locoweed also developed microscopic lesions. This indicated that the locoweed toxin is water soluble and is excreted in the urine.


Assuntos
Bioensaio , Intoxicação por Plantas/veterinária , Ratos , Doenças dos Ovinos/urina , Toxinas Biológicas/urina , Animais , Bioensaio/métodos , Nefropatias/urina , Nefropatias/veterinária , Túbulos Renais Proximais/patologia , Intoxicação por Plantas/patologia , Intoxicação por Plantas/urina , Ovinos , Doenças dos Ovinos/patologia
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