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61.
SLIKKER WILLIAM JR; PAULE MERLE G.; ALI SYED F.; ANDREW C. SCALLET; BAILEY JOHN R. 《Toxicological sciences》1991,17(2):321-334
Chronic Marijuana Smoke Exposure in the Rhesus Monkey I. PlasmaCannabinoid and Blood Carbxyhemoglobin Concentrations and ClinicalChemistry Parameters SLIKKER, W., JR., PAULE, M. G., ALI, S.F., SCALLET, A. C., AND BAILEY, J. R (1991). Fundam. Appl Toxicol17, 321334. This report is the first in a series abouta large multidisciplinary study designed to determine whetherchronic marijuana (MJ) smoke exposure results in residual behavioraland/or neuropathological alterations in the rhesus monkey. Priorto the initiation of a year of chronic MJ smoke exposure, 64periadolescent male rhesus monkeys were trained for 1 year toperform five operant behavioral tasks and then divided, accordingto their performance in these tasks, into four exposure groups(n=1516/group): (1) a high dose (HI) group, exposed 7days/week to the smoke of one standard MJ cigarette; (2) a lowd m (LO) group, exposed on weekend days only to the smoke ofa standard MJ cigarate; (3) an extracted MJ cigarette (EX) group,exposed 7 days/week to the smoke of one ethanol-extracted MJcigarette; and (4) a sham group (SH), exposed 7 days/week tosham exposure conditions. Daily exposures for 1 year were accomplishedusing a mask that covered the subjects' nose and mouth. Averagebody weights (initially 3.7?0.5 kg, mean?SD) and rates of weightgain (approximately 0.1 kg/month) were the same for all groupsthroughout the entire experiment. During the first week of expsure,plasma concentrations of -9-tetrahydrocannabinol and 11-nor-9-carboxy-THCin the HI group were 59?7 (mean?SE) and 5.5?1.5 ng/ml, respectively,45 min after MJ smoke administration and did not change significantlyat similar times after exposure throughout the remainder ofthe year. Whole blood carboxyhemoglobin levels increased toapproximately 13% 1 min after expsure to smoke in either theMJ or the EX groups. Comparison of blood chemistry and hematologyvalues before, during, and after exposure indicated no differencesfor most parameters. During exposure, lymphocytes, alkalinephosphatase and -glutamyl transferase were depressed in theHI group compared to in the SH group. During exposure, aspartateaminotransferase was elevatd for both the HI and EX groups,suggesting a general effect of smoke exposure. Because theseeffects were transient and remained within the range of reportednormal values, these data indicate that long-term, experimentalexperimental exposure to MJ smoke is feasible and does not compromisethe general health of the rhesus monkey. 相似文献
62.
The present study investigated the effect of attention on brain activation in a dichotic listening situation. Dichotic listening is a technique to study laterality effects in the auditory sensory modality. Two different stimuli were presented simultaneously, one in each ear. Twelve subjects listened to lists of consonant-vowel syllables, or short musical instrument passages, with the task of detecting a "target" syllable or musical instrument by pressing a button. The target stimulus appeared an equal number of times in the left and right ear. The subjects were instructed to either concentrate on the stimuli presented in both ears, or only on the left or right ear stimulus. Brain activation was measured with 15O-PET, and significant changes in regional normalized counts (rNC) were evaluated using statistical parametric mapping (SPM96) software. Concentrating on either the right or left ear stimulus significantly decreased activity bilaterally in the temporal lobes compared to concentrating on both ear stimuli, at the expense of an increased activation in the right posterior and inferior superior parietal lobe. The CV-syllables activated areas corresponding to the classic language areas of Broca and Wernicke. The musical instrument stimuli mainly activated areas in visual association cortex, cerebellum, and the hippocampus. An interpretation of the findings is that attention has a facilitating effect for auditory processing, causing reduced activation in the primary auditory cortex when attention is explicitly recruited. The observed activations in the parietal lobe during the focused attention conditions could be part of a modality non-specific "attentional network". 相似文献
63.
Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
相似文献
64.
Epilepsy surgery has emerged as an important option in the treatment of children with epilepsy that is refractory to antiepileptic drug management. The cornerstone of successful surgery is accurate localization of the brain region of seizure onset. Traditional techniques of seizure onset localization, e.g. surface electroencephalography (EEG) recording and magnetic resonance imaging (MRI), allow accurate localization in a significant number of patients. When the focus of seizure onset is not apparent from these non-invasive techniques, other methods of localization, e.g. intracranial EEG recording, may be needed before resection of the focus. Single-photon emission computed tomography (SPECT) is a nuclear medicine blood-flow technique that has been used to identify a region of epileptogenic brain associated with low blood flow in the resting state (interictal SPECT) or increased blood flow at the time of seizure activity (ictal SPECT). This report describes the validation and utility of a computer-assisted method of subtracting the interictal from the ictal SPECT scans and co-registering the difference image on the MRI. This method, called subtraction ictal SPECT co-registered on MRI (SISCOM), is used in guiding the location and the extent of intracranial electrode implantation, or in obviating the need for the implantation in some cases. 相似文献
65.
Monounsaturated fatty acids in serum triacylglycerols are associated with response to neoadjuvant chemotherapy in breast cancer patients 下载免费PDF全文
Mika Hilvo Stephan Gade Tuulia Hyötyläinen Valentina Nekljudova Tuulikki Seppänen‐Laakso Marko Sysi‐Aho Michael Untch Jens Huober Gunter von Minckwitz Carsten Denkert Matej Orešič Sibylle Loibl 《International journal of cancer. Journal international du cancer》2014,134(7):1725-1733
Changes in cellular lipid metabolism are a common feature in most solid tumors, which occur already in early stages of the tumor progression. However, it remains unclear if the tumor‐specific lipid changes can be detected at the level of systemic lipid metabolism. The objective of this study was to perform comprehensive analysis of lipids in breast cancer patient serum samples. Lipidomic profiling using an established analytical platform was performed in two cohorts of breast cancer patients receiving neoadjuvant chemotherapy. The analyses were performed for 142 patients before and after neoadjuvant chemotherapy, and the results before chemotherapy were validated in an independent cohort of 194 patients. The analyses revealed that in general the tumor characteristics are not reflected in the serum samples. However, there was an association of specific triacylglycerols (TGs) in patients' response to chemotherapy. These TGs containing mainly oleic acid (C18:1) were found in lower levels in those patients showing pathologic complete response before receiving chemotherapy. Some of these TGs were also associated with estrogen receptor status and overall or disease‐free survival of the patients. The results suggest that the altered serum levels of oleic acid in breast cancer patients are associated with their response to chemotherapy. 相似文献
66.
新近的临床试验资料,包括2009年美国临床肿瘤协会(ASCO)年会上报道的资料,有力地推动了对晚期非小细胞肺癌(NSCLC)患者的现代治疗策略的改革。此改革蕴含的主题包括:(1)基于组织学类型的治疗,(2)预 相似文献
67.
王虹峥 《中国中医基础医学杂志》1999,(1):30-34
花生过敏是造成人IgE诱导中毒反应的主要原因之一,本试验组制作C3H小鼠动物模型,并给其口服花生蛋白(PN)及霍乱毒素(CTx),然后在腹腔内注射PN(溶于明矾中的PN),使这种鼠即刻发生高度敏感症状(包括致死性的中毒反应)及花生特异性IgE水平增高,血浆息斯地明水平、脱颗粒肥大细胞及血管渗漏水平也大幅度升高。对照组小鼠未给药或仅仅接受了CTx,则未显示出花生特异性IgE水平升高及中毒症状。本文又分析了几种与中毒反应有关的参数。结果证明,小鼠花生过敏中毒反应与人花生过敏类似,同时小鼠花生过敏中毒反应模型,为研究中毒性免疫病理发生机制及研究更有效的治疗方案提供了一个有用的工具。 相似文献
68.
前胡丙素与硝苯啶对大鼠工作心脏缺血再灌注损伤的保护作用 总被引:4,自引:3,他引:4
大鼠ip前胡丙素(Pra-C 15 mg/kg,bid×3d)和硝苯啶(Nif 60μg/kg,bid×3d),使离体缺血再灌注工作心脏的收缩(AP,LVSP,+dP/dtmax)舒张(-dP/dtmax LVEDP和T值)性能在35min时得到改善,尤以舒张性能改善明显,并能促进CO,CF,SV及HR恢复,改善心脏工作效率,减少CK释放和心肌线粒体钙含量,表明Pra-C和Nif对心肌缺血都有保护作用,Pra-C的效应与Nif相近。 相似文献
69.
70.