Using sobriety tests to increase awareness of alcohol impairment

There is a need to investigate methods by which drinkers canbe made aware of their level of alcohol impairment prior todriving. In the current research, 195 students at various bloodalcohol concentration (BAC) levels participated in an evaluationof three simple sobriety tests: a ruler drop/reaction time task,a balance test and a verbal task. Although self-reported measuresof impairment were the best predictors of BAC, both the rulerdrop and body balance tests accounted for significant portionsof BAC variance. These tasks were also perceived by the studentsas reflecting substantial driving ability. Unfortunately, asBAC increased, poor test performance was less likely to resultin a decision not to drive. These results are discussed in termsof the need to continue studying ways to educate drinkers abouttheir level of alcohol impairment so that they can make informeddrinking/driving decisions.     

Non-auditory effects of noise in industry

A review of the literature shows a growing interest in non-auditory effects of noise at work. Somatic, vestibular and psychological effects and different kinds of activity interferences are described. Suggestive evidence of an elevation of the blood pressure by noise exists, although the quality of the studies is limited. Many non-auditory effects can be described in a stress model. Annoyance and stress, however, were seldom the subject of field studies.     

Near-infrared spectrophotometric monitoring of oxygen distribution to intact brain and skeletal muscle tissues

During continuous near-infrared optical monitoring of brain cortex and hindlimb skeletal muscles, anesthetized, ventilated cats were exposed either to progressive alveolar hypoxia, or to acute hemorrhage followed in some cases by resuscitation. Hypoxia decreased cytochrome a,a3 oxidation state in muscle more than in brain, while tissue blood volume increased in brain and decreased in muscle. At a PaO2 of 25 torr, cytochrome a,a3 oxidation level in the brain was sufficient to support EEG activity, but the cytochrome a,a,3 oxidation state in resting, innervated hindlimb muscle was near zero. Hemorrhagic hypotension invariably decreased cytochrome a,a3 oxidation state and tissue blood volume more in muscle than in brain, and muscle cytochrome a,a3 was completely reduced at about a 25-ml/kg blood loss. These observations, supported by noninvasively measured changes in near-infrared absorption in the tissues during serial intravascular injections of indocyanine green dye, indicate that different cytochrome responses to hypoxia and oligemia in muscle vs. brain tissue are attributable to different regional circulatory adjustments.     

Carnitine deficiency associated with ornithine transcarbamylase deficiency

An infant with X-linked recessive ornithine transcarbamylase deficiency is described who also had severe deficiency of plasma and liver carnitine during normoammonemic periods. Treatment with L-carnitine (100 mg/kg/day) for 12 months decreased the frequency of hospitalizations for hyperammonemia, although it did not alter his neurologic status. This report demonstrates that persistent carnitine deficiency may be present in patients with ornithine transcarbamylase deficiency even when plasma ammonia is normal. Carnitine evaluation and supplementation may be important in the treatment of patients with this metabolic disorder.     

Increased plasma cathepsin D concentration in hepatic carcinoma and cirrhosis but not in breast cancer

Using a sandwich enzyme-linked immunoassay, plasma total cathepsin D concentration was assayed in 40 breast cancer patients and 84 patients with various liver diseases and compared to that of 52 normal subjects. There were no significant variations found in breast cancer patients related to tumor size, node invasiveness or metastases. In normal women, cathepsin D levels were slightly but not significantly increased in the luteal phase and in pregnancy. By contrast, plasma cathepsin D concentration was significantly increased in 70-75% of patients with liver disease (cirrhosis, hepatocarcinoma, hepatitis), but not in those with liver steatosis. Cathepsin D was independent of most of the plasma hepatic function tests and was correlated with alpha-fetoprotein in cirrhosis and with alpha-fucosidase in primary hepatocellular carcinoma. We conclude that plasma cathepsin D is not a useful marker in breast cancer. However, since the cellular level of this protease is associated with risk of metastasis in breast cancer, clinical follow-up will be required to test whether high cathepsin D plasma concentration has any prognostic value in liver cirrhosis and primary hepatocarcinoma.     

Marijuana components suppress induction and cytolytic function of murine cytotoxic T cells in vitro and in vivo.

Killer lymphocytes play a major role in host defense against tumors and infectious diseases. Previously, we reported that delta-9-tetrahydrocannabinol (THC) and II-hydroxy-delta-9-tetrahydrocannabinol (II-hydroxy-THC) suppressed the cytolytic activity of cultured natural killer (NK) cells. Also, we showed that the drugs appeared to be affecting a stage in the killing process subsequent to the binding of the killer cell to the target cell. In the present report, we have extended these studies to an examination of the effect of cannabinoids on the activity of cytotoxic T lymphocytes (CTLs). The cytolytic activity of CTLs generated by cocultivation with either allospecific stimulators or TNP-modified-self stimulators were suppressed by both THC and II-hydroxy-THC treatment. Allospecific CTLs generated in vivo were also inhibited by an in vitro exposure to either THC or II-hydroxy-THC, and the sensitivity of these cells to drug effects appeared to be greater than the sensitivity of the in vitro generated CTLs. Suppression of cytolytic function by THC and II-hydroxy-THC was maximal after a 4-h drug treatment, suggesting that the drug effects were inducible and therefore required a finite period of time to develop maximally. As seen in previous studies involving NK cells, drug treatment of mature CTLs appears to have little effect on the binding capacity of these cells for the target. However, the maximal killing capacity of the cells and the frequency of CTLs were significantly reduced by drug treatment. In addition to suppressing the cytolytic activity of mature effector CTLs, we also show that drug treatment inhibits both the proliferation of lymphocytes responding to an allogeneic stimulus and the maturation of these lymphocytes to mature CTLs. Similarly, CTL activity developing in vivo could be inhibited by THC injection. These results suggest that CTLs are inhibited by cannabinoids by at least two mechanisms. First, the cytolytic activity of mature killers is suppressed at some point beyond the binding to the target cell. Second, the cannabinoids appear to suppress the normal development of these mature effector cells from less mature precursor cells.     

A model-based detector of vertex waves and K complexes in sleep electroencephalogram.

A model of sleep phasic events such as vertex waves, K complexes, delta waves and sleep spindles is proposed. It consists of feedback loops that are driven by white noise (simulating tonic delta and sigma activity) and by isolated random impulses, simulating vertex waves or K complexes, depending on the background tonic activity. A model-based method for the detection of sleep phasic events was implemented in a personal computer. Its performance was investigated using simulated and real whole-night EEG signals. The method was able to detect K complexes and vertex waves in a reliable way in spite of their variable shapes and in the presence of a variety of background activities. The detector appears to have superior performance to those so far reported in the literature. The performance of the detector was also compared to that of an electroencephalographer using normal sleep EEG records of 8 h duration from 6 subjects. The performance was satisfactory both in terms of accuracy and reliability. The problem of detecting K complexes in stages 3 and 4 of sleep is discussed.     

Transient entrapment neuropathy of the posterior interosseous nerve in violin players.

Eleven white male right handed violin players complained of transient muscular deficit of the extensor compartment of the left forearm during and after prolonged playing. This was associated with paraesthesiae and pain. Relief was achieved keeping the wrist and the elbow flexed, with the supinated forearm held by the contralateral hand. An anatomical study showed changes of the relationship of the posterior interosseous nerve with its surrounding structures with pronation and supination of the forearm. On the basis of the clinical features, the anatomical studies and the response to a simple physiotherapeutic regime, it is suggested that prolonged pronation of the forearm may cause transient entrapment of the nerve.     

Factor structure of maladaptive behavior across the lifespan of persons with mental retardation

Data obtained on a sample of persons with mild to profound degrees of mental retardation (N = 8255) and ranging from birth to 98 years of age were factor analyzed to provide information on the structure of maladaptive behavior relative to age and degree of mental retardation. Using the Problem Behavior scales of the Inventory for Client and Agency Planning, two principal factors emerged for children with mild to profound degrees of retardation: Internalized Maladaptive and Externalized Maladaptive. For adolescents and young adults, a three-factor solution which varied by degree of retardation was most appropriate. For middle and older adults, three- and four-factor solutions were identified across all ages and degrees of retardation. Across all samples as many as six different types of dimensions were identified, indicating that the structure of maladaptive behavior may well be influenced by age and level of mental retardation.