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Regula E Egli Thomas L Kash Kevin Choo Valentina Savchenko Robert T Matthews Randy D Blakely Danny G Winder 《Neuropsychopharmacology》2005,30(4):657-668
The bed nucleus of the stria terminalis (BNST) and its adrenergic input are key components in stress-induced reinstatement and maintenance of drug use. Intra-BNST injections of either beta-adrenergic receptor (beta-AR) antagonists or alpha2-adrenergic receptor (alpha2-AR) agonists can inhibit footshock-induced reinstatement and maintenance of cocaine- and morphine-seeking. Using electrophysiological recording methods in an in vitro slice preparation from C57/Bl6j adult male mouse BNST, we have examined the effects of adrenergic receptor activation on excitatory synaptic transmission in the lateral dorsal supracommissural BNST (dBNST) and subcommissural BNST (vBNST). Alpha2-AR activation via UK-14,304 (10 microM) results in a decrease in excitatory transmission in both dBNST and vBNST, an effect predominantly dependent upon the alpha2A-AR subtype. Beta-AR activation via isoproterenol (1 microM) results in an increase in excitatory transmission in dBNST, but not in vBNST. Consistent with the work with receptor subtype specific agonists, application of the endogenous ligand norepinephrine (NE, 100 microM) elicits two distinct effects on glutamatergic transmission. In dBNST, NE elicits an increase in transmission (62% of dBNST NE experiments) or a decrease in transmission (38% of dBNST NE experiments). In vBNST, NE elicits a decrease in transmission in 100% of the experiments. In dBNST, the NE-induced increase in synaptic transmission is blocked by beta1/beta2- and beta2-, but not beta1-specific antagonists. In addition, this increase is also reduced by the alpha2-AR antagonist yohimbine and is absent in the alpha2A-AR knockout mouse. In vBNST, the NE-induced decrease in synaptic transmission is markedly reduced in the alpha2A-AR knockout mouse. Further experiments demonstrate that the actions of NE on glutamatergic transmission can be correlated with beta-AR function. 相似文献
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John A. Tomenson Graham A. Matthews 《International archives of occupational and environmental health》2009,82(8):935-949
Purpose The present investigation looks in detail at the causes and types of health incidents reported by 6,300 mainly smallholder
agrochemical users in 24 countries during 2005 and 2006.
Methods The investigation is based on a questionnaire survey of knowledge, attitude and practice that concentrated on the sequence
of events from purchasing the pesticide to disposal. Information was also collected about health problems experienced while
using agrochemicals. The survey targeted mainly smallholder knapsack spray operators who were expected to be at a highest
risk of exposure.
Results In the 12 months prior to interview, 1.2% of users reported an agrochemical-related incident that required hospital treatment,
5.8% reported an incident requiring at least trained medical treatment but not hospitalisation and 19.8% reported only a minor
sign or symptom. Users who had experienced an incident involving agricultural equipment were 3.38 (95% CI 2.29–4.99) times
more likely to experience an agrochemical-related health incident, but confident users who felt that their use of personal
protective equipment while spraying was best practice were 0.60 (95% CI 0.44–0.84) times less likely to experience such an
incident. Over 80% of product-related incidents were caused by insecticides and the incidence rate per spraying time for incidents
linked to insecticides was significantly higher than that for fungicides or herbicides. Headache/dizziness and nausea/vomiting,
often smell related, were the most common symptoms reported by users who listed agrochemical products that had caused them
health problems (52 and 38% of product mentions, respectively).
Conclusions In most countries, the incidence of serious health effects was low; however, there was a high incidence of minor signs and
symptoms in a few countries, especially in Africa. A disproportionate number of incidents occurred during insecticide use
relative to the time that they were sprayed. Failure to exercise caution as indicated by whether users had incidents involving
agricultural equipment or livestock, and lack of confidence in their practices were the most important predictors of agrochemical-related
incidents. 相似文献
5.
The Department of Health has funded a national diabetes network to support clinical research. The network will facilitate recruitment into clinical trials and has been widely welcomed by clinicians. However, if the network is to reach its full potential, all those involved will need to advocate a change in attitude towards clinical trials and research, encouraging participation and contribution of data. Clinicians need to be willing to take a proactive view about research studies, and to encourage patients to adopt a positive and altruistic attitude towards trial participation. The future of trials and other important clinical research in the UK may depend on it. 相似文献
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ZQ Yin MD SG Crewther PhD B Pirie BSc DP Crewther PhD 《Clinical & experimental ophthalmology》1997,25(4):107-109
Purpose: It was investigated whether alterations in neuronal structure and function occasioned by strabismic amblyopia also may be reflected in alterations in the expression on Y type neurons of a Cat-301 antibody sensitive antigen in the lateral geniculate nucleus (LGN) and cortex of our cat model of strabismic amblyopia. Methods/Results: The percentage of positively labelled cells was reduced in LGN laminae that received input from the deviated eye in strabismic amblyopic cats compared with normal cats. In the strabismic cortex, the density of immunopositive neurons was significantly reduced compared with normal, the effect being most pronounced in layer IV Conclusions: Despite previous physiological recordings indicating a decrease in X-cell associated acuity in strabismic amblyopia, the present findings imply that the changes in the early visual experience occasioned by strabismus also produce specific molecular changes in theY neuronal class. 相似文献
8.
Dr. Rex O. Brown Pharm.D. Dr. Roland N. Dickerson Pharm.D. Dr. Emily B. Hak Pharm.D. Dr. J. Barret Matthews M.D. Dr. Lawrence J. Hak Pharm.D. 《Pharmacotherapy》1997,17(4):796-800
A pharmacist consult service was developed to evaluate the appropriateness of enteral feeding through a permanent ostomy in 24 nonambulatory patients with severe developmental disabilities. Several problems with enteral nutrition were identified. Policies to improve them were instituted, and several educational presentations were made. Pharmacists' actions were implemented, including assessment of energy needs by indirect calorimetry and rearrangement of enteral feeding schedules to achieve optimal nutrition support and pharmacotherapy administration. By the fourth month of the consult service, body weight in these patients increased from 101 ± 6% of baseline to 109 ± 7% (p<0.05). Weight continued to increase through the seventh month of the consult service to 116 ± 12% of baseline (p<0.0001). Measured resting energy expenditure for the group was 889 ± 170 kcal/day compared with the predicted 1055 ± 163 kcal/day. 相似文献
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SK&F 86466, 6-chloro-3-methyl-2,3,4,5-tetrahydro-1-H-3-benzazepine, is a potent and selective antagonist of the α2-adrenoceptor in vitro. This compound produced a small pressor response accompanied by a marked bradycardia when administered i.v. to the pithed normotensive rat. The pressor response was not affected by reserpine treatment, pretreatment with α- or β-adrenoceptor antagonists, atropine, or hexamethonium. The bradycardia was markedly reduced by bilateral vagotomy and pretreatment with atropine and attenuated by hexamethonium. The negative chronotropic action of SK&F 86466 was abolished by a combination of vagotomy and atropine. Mediation of the bradycardia by a baroreceptor reflex was ruled out by the observations that a lack of change in heart rate was associated with the vasopressor response to phenylephrine in the pithed rat pretreated with propranolol. It is concluded that the negative chronotropic action of SK&F 86466 in the pithed rat is mediated indirectly by activation of the cholinergic innervation of the heart. 相似文献