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1.
Med Hypotheses ; 132: 109373, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31450077

RESUMO

Immune system dysregulation in 1991 Gulf War Veterans was caused in part by the nerve gas prophylactic drug pyridostigmine bromide (PB) by direct agonist activation of muscarinic receptors on anergic B and T lymphocytes, leading to multiple types of autoimmune illnesses, and this effect may have been potentiated by combat stress.


Assuntos
Doenças Autoimunes/induzido quimicamente , Distúrbios de Guerra/complicações , Agentes Neurotóxicos/efeitos adversos , Síndrome do Golfo Pérsico/etiologia , Brometo de Piridostigmina/efeitos adversos , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Distúrbios de Guerra/psicologia , Guerra do Golfo , Humanos , Agonistas Muscarínicos/efeitos adversos , Síndrome do Golfo Pérsico/psicologia , Receptores Muscarínicos , Estresse Psicológico , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
2.
J Dairy Sci ; 97(9): 5508-20, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24996281

RESUMO

The SLICK haplotype (http://omia.angis.org.au/OMIA001372/9913/) in cattle confers animals with a short and sleek hair coat. Originally identified in Senepol cattle, the gene has been introduced into Holsteins. The objectives of the current study were to determine (1) whether lactating Holsteins with the slick hair phenotype have superior ability for thermoregulation compared with wild-type cows or relatives not inheriting the SLICK haplotype, and (2) whether seasonal depression in milk yield would be reduced in SLICK cows. In experiment 1, diurnal variation in vaginal temperature in the summer was monitored for cows housed in a freestall barn with fans and sprinklers. Vaginal temperatures were lower in slick-haired cows than in relatives and wild-type cows. In experiment 2, acute responses to heat stress were monitored after cows were moved to a dry lot in which the only heat abatement was shade cloth. The increases in rectal temperature and respiration rate caused by heat stress during the day were lower for slick cows than for relatives or wild-type cows. Moreover, sweating rate was higher for slick cows than for cows of the other 2 types. In experiment 3, effects of season of calving (summer vs. winter) on milk yield and composition were determined. Compared with milk yield of cows calving in winter, milk yield during the first 90 d in milk was lower for cows calving in the summer. However, this reduction was less pronounced for slick cows than for wild-type cows. In conclusion, Holsteins with slick hair have superior thermoregulatory ability compared with non-slick animals and experience a less drastic depression in milk yield during the summer.


Assuntos
Regulação da Temperatura Corporal/genética , Bovinos/genética , Transtornos de Estresse por Calor/genética , Transtornos de Estresse por Calor/veterinária , Lactação , Animais , Feminino , Loci Gênicos , Técnicas de Genotipagem , Cabelo , Haplótipos , Temperatura Alta , Abrigo para Animais , Modelos Lineares , Leite , Polimorfismo de Nucleotídeo Único , Taxa Respiratória , Estações do Ano
3.
Med Hypotheses ; 81(6): 1002-3, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24095261

RESUMO

Sodium chloride intake might increase the risk for the development of autoimmune diseases by increasing the activity of the p38/MAPK pathway in CD4+ cells thereby producing pathogenic TH17 cells which are inflammatory. Two factors (muscarinic and beta adrenergic stimulation), already shown to potentiate each other's toxic effects in whole mice, and have combined amplified sub lethal effects on mouse T cells, can have the same effect on CD4+ signaling pathways as sodium chloride. Sick 1991 Gulf War veterans express elevated Th17 cytokine activity, and therefore may have autoimmune illnesses caused directly by the above mentioned exposures.


Assuntos
Albuterol/efeitos adversos , Doenças Autoimunes/etiologia , Linfócitos T CD4-Positivos/imunologia , Sistema de Sinalização das MAP Quinases/imunologia , Modelos Biológicos , Síndrome do Golfo Pérsico/etiologia , Brometo de Piridostigmina/efeitos adversos , Albuterol/metabolismo , Animais , Doenças Autoimunes/imunologia , Humanos , Camundongos , Síndrome do Golfo Pérsico/imunologia , Brometo de Piridostigmina/metabolismo , Cloreto de Sódio/efeitos adversos , Células Th17/imunologia
4.
J Anim Sci ; 90(11): 3762-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22665658

RESUMO

Development of the mammalian preimplantation embryo is susceptible to disruption by elevated temperature. The molecular and biochemical bases for developmental, genetic, and other differences in embryonic resistance to heat shock are largely not known. Here we tested the hypothesis that increasing free cholesterol content could improve embryonic resistance to heat shock. Culture of bovine embryos at 41.0°C for 15 h beginning at 30 h after insemination (1- to 2-cell stage) reduced development to the blastocyst stage. Reduction in embryonic cholesterol content by culture with methyl-ß-cyclodextrin (MBCD) reduced development. This effect of MBCD could be abrogated in 1 of 2 experiments if the molecule was loaded with cholesterol before addition to culture medium. Even though culture with cholesterol-loaded MBCD increased free cholesterol content, it did not increase resistance of embryos to heat shock. Treatment of embryos with cholesterol-loaded high density lipoprotein (HDL) increased embryonic resistance to heat shock even though it slightly reduced embryo cholesterol content. It is likely that other actions of HDL (e.g., protection from free radicals) were responsible for the thermoprotective properties of this molecule. A final experiment was performed to determine whether the increased resistance of embryos at d 5 of development to heat shock as compared with the 2-cell embryo was due to changes in free cholesterol content. However, there was no significant difference in cholesterol content between 2-cell embryos and d 5 embryos that were > 16 cells in development. In conclusion, raising cholesterol content does not improve embryonic survival in response to heat shock. Depletion of cholesterol, in contrast, reduces competence of embryos to develop to the blastocyst stage. High density lipoprotein is thermoprotective to embryos and probably acts through a mechanism independent of its actions on embryonic content of free cholesterol.


Assuntos
Blastocisto/fisiologia , Bovinos/embriologia , Colesterol/metabolismo , Temperatura Alta , Lipoproteínas HDL/metabolismo , Animais , Blastocisto/efeitos dos fármacos , beta-Ciclodextrinas/farmacologia
5.
Med Hypotheses ; 79(2): 283-4, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22632735

RESUMO

Gulf War illnesses (GWI share many of the features of chronic fatigue syndrome (CFS) and both CFS and GWI may be the result of chronic immune system processes. The main suspected cause for GWI, the drug pyridostigmine bromide (PB), has been shown to cause neuronal damage from reactive oxygen species (ROS). ROS have been associated with IgM mediated autoimmune responses against ROS induced neoepitopes in depressed patients and this may also apply to CFS. It therefore follows that the drug used in the Gulf War caused ROS, the ROS modified native molecules, and that this trigged the autoimmune condition we refer to as Gulf War illnesses. Similar mechanisms may apply to other autoimmune illnesses.


Assuntos
Doenças Autoimunes/induzido quimicamente , Doenças Autoimunes/metabolismo , Substâncias para a Guerra Química/intoxicação , Síndrome do Golfo Pérsico/induzido quimicamente , Síndrome do Golfo Pérsico/metabolismo , Brometo de Piridostigmina/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Inibidores da Colinesterase/efeitos adversos , Inibidores da Colinesterase/uso terapêutico , Humanos , Modelos Biológicos , Brometo de Piridostigmina/uso terapêutico
6.
Med Hypotheses ; 56(2): 155-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11425278

RESUMO

Gulf War-related illnesses are mostly common ailments, but with incidence rates that exceed those expected in the population of Gulf War veterans. These illnesses may be the result of combinations of chemical and physiological stressors which may have caused acute cellular effects sufficient to initiate processes of autoimmunity to various organs, tissues or types of cells. Two main suspects in the Gulf War cluster of illnesses are the 'Nerve Gas Pill' (pyridostigmine bromide, PB, NAPS) and stress. One component of stress, beta-adrenergic load, potentiates the toxicity of PB. While similar types of chemical and physiological stressors are present in the general population, the Gulf War veteran population received these stressors in a short time, with greater intensity, and at a higher percentage exposure than normal for the general population. This may be an opportunity to learn the cause, how to prevent, and, possibly, how to treat these ailments in Gulf War veterans and in the general population.


Assuntos
Doenças Autoimunes/induzido quimicamente , Epinefrina/fisiologia , Síndrome do Golfo Pérsico/induzido quimicamente , Brometo de Piridostigmina/efeitos adversos , Estresse Fisiológico/fisiopatologia , Epinefrina/biossíntese , Humanos
7.
Vet Hum Toxicol ; 39(4): 214-9, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9251170

RESUMO

Pyridostigmine bromide (PB) is a reversible cholinesterase inhibitor used routinely in the treatment of myasthenia gravis and recently by the US Army as a prophylactic agent against potential nerve gas attack in the Persian Gulf War. Pyridostigmine has been implicated as one of several possible causative factors associated with Persian Gulf illnesses. To investigate toxic interactions between PB and other drugs, male ICR mice received contralateral ip injections of either a selected adrenergic drug or caffeine, followed 15 min later by PB. Representative isobolograms plotted for each drug interaction illustrate that a beta-adrenoceptor agonist (isoproterenol), selective beta 2-adrenoceptor agonists (salbutamol, terbutaline), alpha 1- and alpha 2-adrenoceptor antagonists (yohimbine, phentolamine, prazosin), as well as the stimulant caffeine, strongly potentiate the lethal effect of PB. Agents with agonist activity at both alpha- and beta-adrenoceptors (epinephrine, norepinephrine) additively increase PB-induced lethality. The potentiation of toxicity between PB and these agents was counteracted by pretreatment with atropine and atropine methyl nitrate. An alpha 2-adrenoceptor agonist (clonidine) and beta-adrenoceptor antagonists (propranolol, nadolol, acebutolol) did not increase PB-induced lethalities. These data demonstrate a toxic synergism between PB, several commonly used classes of adrenergic agents and caffeine when exposure occurs in different combinations. Future studies into the mechanism(s) of these interactions may bring into question the usage of PB as a protective agent in combat conditions as well as delineate any possible contributions of the drug to Persian Gulf illnesses.


Assuntos
Adrenérgicos/toxicidade , Cafeína/toxicidade , Estimulantes do Sistema Nervoso Central/toxicidade , Inibidores da Colinesterase/toxicidade , Brometo de Piridostigmina/toxicidade , Animais , Sinergismo Farmacológico , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos ICR , Taxa de Sobrevida
9.
J Econ Entomol ; 89(5): 1151-5, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17450648

RESUMO

Various compounds were tested for effects on the toxicity of the insect repellent N, N-diethyl-m-toluamide (DEET) in German cockroaches, Blattella germanica (L.). Organophosphate and carbamate acetylcholinesterase inhibitors carbaryl, DEF, eserine (physostigmine, malathion and pyridostigmine bromide synergized DEET toxicity also synergized the toxicity of the formamidine pesticides. Amitraz and chlordimeform. Results suggest that DEET may have some toxic actions that are similar to those of formamidine pesticides. DEET synergized the toxicity of some acetylcholinesterase inhibitors but not others. Results further suggest that some mechanism other than acetylcholinesterase inhibition was responsible for the toxic interactions observed between DEET and the acetylcholinesterase inhibitors.


Assuntos
Blattellidae , Inibidores da Colinesterase/toxicidade , DEET/toxicidade , Repelentes de Insetos/toxicidade , Animais , Sinergismo Farmacológico , Inseticidas/toxicidade , Dose Letal Mediana , Masculino , Modelos Animais , Fisostigmina/toxicidade
10.
J Econ Entomol ; 87(6): 1534-6, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7836612

RESUMO

Oral toxicity was characterized in first-instar cat fleas, Ctenocephalides felis felis (Bouché), feeding on dried blood treated with boric acid. LC50 values ranged from 2.11% after 24 h to 0.21% after 7 d. In carpet tests with five different boron compounds and a number of different formulations, significant mortality for first instars was observed in all cases. In similar tests with prepupae and cocoons, there was no significant effect on mortality. The importance of these results is discussed in light of current application procedures for boron compounds, and suggestions are made for future research.


Assuntos
Ácidos Bóricos/toxicidade , Sifonápteros/efeitos dos fármacos , Administração Oral , Animais , Ácidos Bóricos/administração & dosagem , Compostos de Boro/administração & dosagem , Compostos de Boro/toxicidade , Gatos , Larva/efeitos dos fármacos , Dose Letal Mediana , Pupa/efeitos dos fármacos
11.
J Econ Entomol ; 85(5): 1601-5, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1401478

RESUMO

Glue that contained an insecticide was evaluated for its ability to yield useful toxicological data for German cockroaches, Blattella germanica (L.). Toxicities of three classes of insecticides were evaluated by topical applications (LD50) and exposure to insecticide-impregnated glue (LC50). Cockroaches that were resistant to topical insecticide applications were also resistant to the glue formulation. Reliability was greatest when mortality was scored 40 to 48 h after the cockroaches were placed on the glue. This method should be adaptable for insecticide resistance monitoring of German cockroaches.


Assuntos
Baratas , Resistência a Inseticidas , Adesivos , Animais , Masculino
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