Immediate memory, attention and communication disturbances in schizophrenia patients and their relatives

BACKGROUND: Schizophrenia has been defined in part by disturbances of thought and language. The non-schizophrenic relatives of patients also have been found to show subtle disturbances of language that may be associated with vulnerability. Investigators have hypothesized that these phenomena in patients and their relatives are, at least in part, the result of weaknesses in facets of attention and memory. METHODS: The present study assessed some neuropsychological process correlates of three different measures of thought and language symptoms in 55 stable out-patients, using tests of immediate auditory memory impairment and auditory distractability, and carefully controlling for generalized deficit effects. A parallel assessment was made of referential communication disturbances in 59 non-schizophrenic relatives of patients and 24 control subjects matched to the relatives. RESULTS: In patients, formal thought disorder, disorganization, and referential communication disturbances were all associated with each other and with auditory distractability. In addition, as expected, referential communication disturbances were associated with immediate auditory memory impairment. Referential disturbance ratings for relatives were similar in magnitude to those for the stable out-patients, and much higher than for controls. However, the relatives' language ratings were not associated specifically with weaknesses in attention or memory as measured. CONCLUSIONS: Impairments in immediate auditory memory and attention are associated differentially with different types of communication disturbances in schizophrenia patients. The cognitive substrate for referential communication disturbances in relatives appears to differ qualitatively from that for patients.     

The effects of resistance training on aerobic and anaerobic power of young boys

A 4-wk interval-type training program incorporating omni-kinetic equipment and stationary cycling elicited an increase in the absolute and relative VO2max of an active group of young boys. The improvement in aerobic function was independent of the training protocols of high velocity-low resistance and low velocity-high resistance. However, the training programs failed to increase anaerobic function as measured by an "all-out" cycle test in which power output was calculated in watts and watts per kilogram for 0- to 15-s and 15- to 30-s work periods. Changes in aerobic and anaerobic functions were independent of physiological maturity as determined by serum testosterone level (ng X dl-1).     

EFFECT OF NITROGLYCERNE-INDUCED HYPOTENSION ON CANINE SPINAL CORD BLOOD FLOW

Twenty-four mongrel dogs were anaesthetized with pentobarbitoneand morphine sulphate. Neuromuscular blockade was achieved usingpancuronium. Spinal cord blood flow was measured using the radionuclidemicrosphere and hydrogen washout methods before, during, andfollowing nitroglycerine-induced hypotension. Heart rate, meanarterial pressure, cardiac output, pulmonary capillary wedgepressure, and acid-base balance were determined with each measurement.Mean arterial pressure was reduced by 50%. Spinal cord bloodflow, as measured by the microsphere method, increased duringthe period of hypotension, whereas values obtained using thehydrogen washout method were not significantly different fromthose at normotension. No significant change in spinal cordblood flow was detected by either method after the applicationof spinal distraction. Nitroglycerine acts predominantly onvenous capacitance vessels and it is postulated that perfusionpressure, and therefore flow, is maintained despite a reductionin arterial pressure. Presented in part at the Anual Meeting of the American Societyof Anesthesiologists, October 1985, San Francisco, California. ^*Shackleton Department of Anaesthetics, Southampton GeneralHospital, Shirley, Southampton, Hants SO9 4XY. Section of Orthopedic Surgery, Madison, Wisconsin.     

The Effects of Magnetic Resonance Imaging on Implantable Pulse Generators

The effects of magnetic resonance imaging were assessed on four dual chamber and two single chamber pulse generators. The tests were performed with a resistive, water-cooled magnet operating at 0.15 T. The 6.4-MHz radiofrequency (RF) field was operated at a maximum power of 1,000 watts with a period adjusted from 130 to 500 ms. Reed switch closure occurred in all six pulse generators tested when placed near the entrance of the magnetic resonance imaging scanner, and the generators reverted to asynchronous operation unless programmed to the "magnet off" mode. None of the pulse generators exhibited any alterations in programmed parameters or in the ability to be reprogrammed after RF pulsing. When the RF field was turned on, there was no change in the asynchronous paced cycle length in four pulse generators; however, during RF scanning there was rapid cardiac stimulation at the RF pulse period in one single chamber and one dual chamber pulse generator.     

Developmental Neurotoxicity: Evaluation of Testing Procedures with Methylazoxymethanol and Methylmercury

Testing procedures for identification of potential developmentalneurotoxicants were evaluated using two prototypical developmentalneurotoxicants, methylazoxymethanol (MAM) and methylmercury(MeHg). Evaluation of offspring of LongEvans rats incorporatedassessments of developmental toxicity, neurochemistry, histology,and behavior, with most testing being completed near weaning.A number of endpoints in the testing strategy were sensitiveto the effects of prenatal exposure to MAM [30 mg/kg on GestationDay (GD) 15]: (1) MAM caused reduced neonatal body weights butdid not effect viability or postnatal survivorship; (2) measurementof total and regional brain weight and histological analysisshowed that a number of regions, the cortex and hippocampusin particular, were affected by MAM exposure; (3) an assay forglial fibrillary acidic protein (GFAP) showed that the concentrationof this protein was significantly increased in the cortex andhippocampus of treated offspring; (4) a T-maze delayed-alternationprocedure indicated that MAM-treated pups were slower in theacquisition phase of the task relative to control pups; (5)motor activity testing revealed hyperactivity in treated offspringthat persisted into adulthood; and (6) acoustic startle proceduresrevealed reduced startle amplitudes in preweanlings. Few endpointswere significantly affected by prenatal MeHg exposure (1, 2,or 4 mg/kg on GD 6–15). High fetal and neonatal mortalityand lower neonatal body weights were detected at the highestdose of MeHg. Although minimal effects of MeHg may reflect arelative insensitivity of the test species and/or the test methods,the combined results from both chemicals suggest that some proceduresnot currently required in the developmental neurotoxicity guidelinemay be useful in hazard identification, and further evaluationwith other chemicals, species, strains, and/or exposure paradigmsmay be warranted.     

Health promotion in the Scottish workplace: a case for moving the goalposts

The workplace provides an important opportunity for health promotion, both in terms of allowing access to a large proportion of the adult population and encouraging developments within the workplace structure to improve health. This paper reports on the findings of a survey of Scottish workplaces carried out in 1996 for the Health Education Board for Scotland to assess the state of health promotion activity in the Scottish workplace setting. The results echo those from previous surveys in that most health promotion effort was centred around health and safety, smoking, and alcohol issues, particularly for the smaller and less well-resourced businesses. Under one-fifth of businesses surveyed addressed areas such as stress and mental health, which are being seen as increasingly important in terms of their contribution to the well-being of the employee and the organization. The main implication of these findings is that it is smaller businesses who potentially have the most to gain from workplace health promotion. In this context, the construction of relevant and sustainable health promotion programmes requires an organizational development perspective in order to encourage such businesses to regard workplace health promotion as part of good business practice.     

Chronic Marijuana Smoke Exposure in the Rhesus Monkey I. Plasma Cannabinoid and Blood Carboxyhemoglobin Concentrations and Clinical Chemistry Parameters

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, 321–334. 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=15–16/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.     

The effectiveness of voice therapy for patients with non-organic dysphonia

Forty-five patients diagnosed as having non-organic dysphonia were assigned in rotation to one of three groups. Patients in one group received no treatment and acted as a control group. Patients in the other two groups received a programme of either ‘indirect’ therapy or ‘direct with indirect’ therapy, respectively. A self-report questionnaire of vocal performance, observed ratings of voice quality, and computer-derived acoustic measurements (signal-to-noise ratio, pitch perturbation and amplitude perturbation) were carried out on all patients before and after treatment to evaluate the changes in voice quality over time. There was a significant difference between the three groups on the self-report questionnaire, voice quality ratings and pitch perturbation measurements (P = < 0.05). Thirteen out of 15 control patients showed no significant change on any of the measures. Seven patients who received indirect treatment showed significant improvement in voice quality following treatment. Fourteen out of 15 patients who received direct treatment showed significant improvement in voice quality.     

Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer

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.      

Advances in computer-assisted single-photon emission computed tomography (SPECT) for epilepsy surgery in children

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.