Effects of immunosuppression and disease severity upon neuropsychological function in HIV infection

Effects of immunosuppression and illness severity upon neuropsychological function were assessed in a group of homosexual men with AIDS across 6 months. Participants included 62 who were seronegative (HIV-), 74 asymptomatic seropositives (HIV+A), 31 symptomatic seropositives (HIV+S), 23 with AIDS defining illnesses (AIDS-DI), and 10 who were diagnosed with AIDS solely on the basis of CD4+ levels falling below 200 /mm3 (AIDS-CD4). Groups were equivalent in age, education, and IQ. None were drug users, and none experienced a change in disease status across the 6-month inter-test interval. There was little evidence of cognitive decline across time. Nonetheless, after collapsing across time intervals, the AIDS-DI group had worse new-learning than all other groups. Additionally, the AIDS-DI demonstrated a greater number of impaired performances than the other participant groups. The data suggest that cognitive impairment in AIDS is unlikely due to independent contributions of immunosuppression and illness. Rather neurobehavioral deficits are more likely attributable to a combination of the two.     

Effects of abstinence and relapse upon neuropsychological function and cerebral glucose metabolism in severe chronic alcoholism

Abstract

Prolonged excessive consumption of alcohol has been associated with a variety of cognitive disorders accompanied by neuropathological and neurochemical abnormalities of the brain, particularly in the frontal lobes. Studies with positron emission tomography (PET) have shown decreased local cerebral metabolic rates for glucose (ICMRglc) in frontal regions, with correlated abnormalities on neuropsychological tests sensitive to executive functioning. This investigation was designed as a pilot study to examine the effects of abstinence and relapse in patients with severe chronic alcoholism studied longitudinally with PET and with neuropsychological evaluation to assess both general and executive functioning. Six patients, including 4 who remained relatively abstinent and 2 who relapsed following their initial evaluation, were studied twice, with inter-evaluation intervals ranging from 10 to 32 months. The patients who remained abstinent or who had minimal alcohol use showed partial recovery of ICMRglc in two of three divisions of the frontal lobes and improvement on neuropsychological tests of general cognitive and executive functioning, whereas the patients who relapsed had further declines in these areas. These results, although based upon a relatively small number of subjects, provide preliminary support for at least partial recovery of metabolic and cognitive functioning in individual patients who abstain from alcohol.     

Effect of quinine on the calcium currents of mollusk neurons

The effects of quinine on the peak amplitude and relaxation of calcium current (ICa) were examined on isolated unidentified snail neurons. Quinine (1 X 10(-5)-5 X 10(-4) mol/l) reversibly slowed the relaxation of ICa in a dose-dependent manner (early effect) and suppressed the peak amplitude of ICa in a dose-dependent and time-dependent manner (delayed effect). Quinine induced a shift of the current-voltage relationship for peak ICa by 5-10 mV in the hyperpolarizing direction. A half inhibition of ICa peak amplitude was induced by 6 X 10(-5) mol/l quinine. The results show that quinine is an effective inhibitor of calcium channels in snail neurons.     

Human callosal function: MRI-verified neuropsychological functions

A commissurotomy patient, with MRI-revealed sparing of some rostral and splenial fibers of the corpus callosum, judged whether pairs of words rhymed. We presented one word in each pair to her left visual field and the other to her right visual field. The 2 words in each pair either sounded and looked alike (R + L +), sounded alike but looked different (R + L -), sounded different but looked alike (R - L +), or both sounded and looked different (R - L -). Although in previous studies the patient has demonstrated little or no ability to transfer information between her brain hemispheres, she was able to perform the rhyming judgment significantly better than chance when the words both looked and sounded alike. However, her accuracy did not differ from chance in the other 3 conditions, or when she was asked to indicate if 2 letters presented to her opposing visual fields were the same or different. A second commissurotomy patient, with an MRI-verified full callosal section, performed at chance in all conditions, and normal control subjects were significantly better than chance in all conditions but R + L -. We discuss the results in terms of the specificity of the information carried by groups of callosal fibers.     

Impact of HIV and aging on neuropsychological function

Cognitive efficiency decreases with age, and advancing age is the leading risk factor for most neurodegenerative disorders that result in dementia. In HIV infection, risk for cognitive impairment is consistently linked to advancing chronological age. As the HIV epidemic enters its fourth decade in the USA, extended life expectancy will likely result in an increased prevalence of cognitive disorders by virtue of these factors. However, it is less clear if HIV potentiates or accelerates the risk for cognitive impairment given that most reports are mixed or demonstrate only a small interaction effect. More critically, it is unclear if HIV will modulate the neuropathology associated with non-HIV cognitive disorders in a manner that will increase risk for diseases such as cerebrovascular and Alzheimer's disease. In the coming years, with increasing numbers of HIV+ patients entering their 60s and 70s, background risk for neurodegenerative disorders will be sufficiently high as to inform this issue on clinical grounds. This review summarizes knowledge of cognition in HIV as it relates to age and presents some emerging controversies.     

Changes in platelet function and reactivity induced by quinine in relation to quinine (drug) induced immune thrombocytopenia

Quinine, a drug known to induce immune mediated thrombocytopenia, has been postulated to mediate binding of drug dependent antibodies to a range of platelet membrane glycoproteins. Quinine may not act solely as a hapten however, as we have shown that it inhibits platelet aggregation ( and ) and release and modifies the ability of activated platelets to bind the adhesive proteins fibrinogen and fibronectin in a dose dependent fashion. Studies on the effect of quinine on the binding of monoclonal antibodies HuPlml (GpIIIa) FMC25 (GpIX) and AN51 (Gplb) to platelets shows a selective reduction in AN51 binding. In addition quinine induced platelet antibodies from thrombocytopenic patients, in the presence of quinine, have been shown to inhibit binding of these monoclonal antibodies to platelets to varying degrees. These observations suggest that quinine causes widespread but specific conformational changes in platelet membrane antigens which may expose neoantigens resulting in the production of quinine induced antibodies.     

Psychosocial and neuropsychological function in children with epilepsy

This paper reviews the psychosocial and neuropsychological effects of epilepsy on children and families across environments in which children function, specifically home and school. Epilepsy is a chronic disorder, affecting one percent of the population, that alters neurocognitive functioning effecting learning, memory and family adaptation. A review of epilepsy and its impact on quality of life, family and school function and psychiatric comorbidity are discussed.     

Probing prefrontal function in schizophrenia with neuropsychological paradigms

In a recent series of studies we have attempted to clarify the nature of intellectual impairment in schizophrenia, and in particular, how patterns of dysfunction implicate specific neural systems. First, we found that acute psychotic adolescent patients displayed the same pattern of IQ scores (Performance less than Verbal) as adult chronic schizophrenic patients. We explored this deficit in problem solving by studying the performance of schizophrenic patients after receiving concrete and explicit instructions on how to do the Wisconsin Card Sorting Test, a task thought to be mediated by prefrontal cortex. We then studied the differential impact such a deficit in problem-solving strategies might have on a task thought to elicit both cognitive (prefrontal) and procedural or motor-skill (basal ganglia) processing. Procedural components appeared to be relatively more intact. We also addressed schizophrenic patients' ability to learn in other (extrafrontal) cognitive domains through verbal memory tasks and block design puzzles. Learning occurred under both conditions. We believe the overall pattern of deficit implicates primarily prefrontal neural systems, though a number of other neuropsychological functions are yet to be surveyed.     

HIV proviral DNA associated with decreased neuropsychological function

The authors previously found a strong association between elevated HIV proviral DNA (HIV DNA) and a diagnosis of HIV-1-associated dementia (HAD) vs. normal cognition. It is unclear whether HIV DNA globally affects the diagnosis of HAD or whether the effect is limited to individual neuropsychological deficits. This exploratory study examined baseline HIV DNA and its association with individual neuropsychological deficits. HIV DNA was significantly associated with baseline neuropsychological deficits independent of age, ethnicity, IQ, and plasma HIV-1 RNA levels. However, HIV DNA did not predict future changes in neuropsychological deficits. The data suggest that HIV DNA and neuropsychological deficits may co-vary over time.     

Effect of quinine on electroshock and pentylenetetrazol-induced seizures in mice

1. Effect of quinine on electroshock and pentylenetetrazol (leptazol)-induced seizures was investigated in mice. 2. Quinine (0.1-100 mg/kg, ip) did not protect mice against electroshock seizure. 3. 25-100 mg/kg, ip of quinine reduced the incidence of leptazol (80-90 mg/kg, sc)-induced seizure and significantly prolonged the onset of both myoclonic and tonic phases. 4. d-Amphetamine (2.5 mg/kg, ip), inhibited the protective effect of quinine (100 mg/kg, ip) against leptazol (80-90 mg/kg, sc)-induced seizure and significantly shortened the onset of both myoclonic and tonic phases of the seizure. 5. Pimozide (4 mg/kg, ip) significantly potentiated the protective effect of quinine (50-100 mg/kg, ip) against leptazol (80-90 mg/kg, sc)-induced seizure. 6. These results suggest that quinine in moderate doses, may have slight anticonvulsant properties and that dopaminergic mechanism may be involved in the protective influence of quinine against leptazol-induced seizure in mice.     

Variable benefit in neuropsychological function in HIV-infected HAART-treated patients

The authors examined cognitive performance change in 101 individuals with advanced HIV infection on highly active antiretroviral therapy (HAART), using standard neuropsychological testing in three visits, over a 27-month-period. Cognitive performance stabilized in a majority of HIV+ participants over time. A neuroactive HAART regimen was associated with neuropsychological improvement. Decline occurred in a minority with lower nadir CD4. The current CD4 count and plasma viral load were not associated with cognitive change.     

A follow-up study of neuropsychological function in asymptomatic HIV-infected patients

A group of asymptomatic HIV-infected patients (CDC II and III) was followed-up over a two year period with semi-annual neuropsychological testing. Of the total sample of 36 subjects, all were retested at test two (T2), 19 at test three (T3) and 13 at test four (T4). A subgroup of subjects was further tested on a simple and a complex task of reaction time. The CD4 + and CD8 + lymphocyte counts were measured in peripheral blood. According to our criteria, no patient could be defined as neuropsychologically impaired. A significant improvement in performance was found from T1 to T2 and from T2 to T3, with a leveling off between T3 and T4. No associations were observed between reaction time and changes in neuropsychological test results and immunological parameters. Our results indicate that neuropsychological impairment does not develope gradually in the asymptomatic stages of HIV-infection. Furthermore, measurements of reaction time do not seem to have any prognostic significance neither for neurocognitive function nor for immunological status as measured by us.     

Effect of cigarette smoking upon in vivo platelet function in man

In vivo platelet aggregation, measured by the Filtragometer procedure in the presence of all formed elements of the blood, is significantly increased after cigarette smoking. This effect appears to be independent of the nicotine concentration of the cigarette. The absorbed carbon monoxide content of the smoke, as noted by increased carboxy-hemoglobin, appears to be related to the alterations in platelet function that were noted, and may be an extremely important factor in mediating cigarette smoking's noxious effects.     

尼麦角林治疗偏头痛的疗效及对神经心理因素的影响

目的：探讨尼麦角林治疗偏头痛的疗效及对神经心理因素的影响。方法138例偏头痛患者随机分为2组,治疗组口服尼麦角林片10 mg ,3次/d ,同时在疼痛发作时口服双氯芬酸钠片50 mg ,q12h;对照组仅在发作时口服双氯芬酸钠。所有患者入组时进行16PF测定;治疗前及治疗后2周及8周进行HAMA、HAMD评定及疼痛指数测定。结果16PF评定显示偏头痛患者恃强性、敏感性、怀疑性、幻想性、忧虑性、自律性、紧张性因子分高于正常人常模,差异有统计学意义（P＜0.05）。治疗组疗效优于对照组,差异有统计学意义（P＜0.05）。第8周末治疗组AMD、HAMA评分及减分率较对照组差异有统计学意义（ P＜0.05）。结论联合应用尼麦角林及发作期使用双氯芬酸钠对症治疗偏头痛可提高疗效,同时改善焦虑及抑郁情绪。     

Effect of visual impairment on neuropsychological test performance

Abstract

Three vision-dependent neuropsychological tests of visual processing - Benton's Facial Recognition (FR), Judgment of Line Orientation (JLO), and Visual Form Discrimination (VFD) - were administered to subjects on the same day as routine ophthalmic examination. Seventeen subjects had Jaeger near vision of J5 (analogous to 20/50) or worse resulting from refractive error, while 13 control subjects had normal near vision of J1. Neuropsychological test scores of these groups were compared with each other and also the published standardization group for each test. Low near-vision subjects' performances on FR and VFD were significantly poorer than both control group subjects and standardization group subjects, but performance on JLO was not significantly altered. These results demonstrate that visual impairment can result in unexpectedly low scores on certain tests of visual processing, which suggests that poor vision might also affect results of other neuropsychological tests that involve vision, such as tests of visual processing and tests which use vision as a vehicle to deliver test stimuli to the relevant portions of the cortex. We therefore strongly urge examiners to secure control over potential bias resulting from reduced vision by instituting routine near visual acuity testing of all subjects prior to or during neuropsychological assessment.     

Neuroleptics: effects on neuropsychological function in chronic schizophrenic patients

We have reviewed the literature from the 1950's to the present on the effects of neuroleptics on perceptual and neuropsychological function in chronic schizophrenic patients. In contrast to previous reviews, we have delineated the acute and chronic effects of neuroleptics on individual cognitive and motor tasks by drug, dose, and length of administration. To date, studies have shown that acute administration of neuroleptics impairs performance on some, but not all, tasks requiring vigilance and attention, and on some tasks requiring motor behavior. Chronic administration of neuroleptics, however, improves performance on some tasks requiring sustained attention and visuomotor problem-solving skills depending on dose and length of administration. Moreover, there is consistent evidence to suggest that chronic administration of neuroleptics in this patient population does not impair neuropsychological function independent of motor function. These findings have direct implications regarding the risk/benefit ratio and legal ramifications for the use of neuroleptics in chronic schizophrenic patients.     

Visual processing and neuropsychological function in schizophrenia and schizoaffective disorder

Persons with schizophrenia and schizoaffective disorder exhibit deficits in both visual processing and neuropsychological tasks. Little is known, however, about whether these deficits are related to one another. We administered psychophysical tests of visual discrimination and recognition, and neuropsychological tests of abstract flexibility, verbal learning, visual memory, working memory and attention to 42 outpatients with stable but chronic schizophrenia or schizoaffective disorder. Multiple regression analyses were performed to determine the relationship between these measures of neuropsychological function and visual psychophysical performance. Results indicated that motion perception was associated with working memory, and that the addition of a memory component to motion perception (motion recognition) was associated with both working memory and visual memory. Visual performance was not associated with symptom severity as measured by the PANSS. These results suggest that psychophysical tests of visual processing may contribute to deficits on neuropsychological tests of visual cognition, and may also reflect cross-modal disturbances of working memory function.     

Duration effect on neuropsychological function and treatment response of OCD]

Because of inconsistency among previous reports that examined neuropsychological function and treatment response of OCD patients, we here consider the heterogeneity of OCD; for example: symptom-based clusters, degree of insight, age of onset, and comorbid diagnoses. In this study, we examined neuropsychological function and the treatment response of OCD patients. Thirty-two OCD patients participated in this study. We examined their clinical symptoms by Y-BOCS, MOCI and other scales, and examined their cognitive function with several neuropsychological tests including: WAIS-R, Stroop test, WCST, WMS-R and R-OCFT. We then randomly assigned them to three treatment packages including: behavior therapy, pharmacotherapy by fluvoxamine, and controlled therapy. The patients were divided into two groups by duration of illness: short to middle range group (Group S, n=17, 5.5+/-3.1 years), and long range group (Group L, n=15, 20.3+/-6.1 years). The mean age of Group L was higher than that of Group S (Group S: 30.6+/-9.7 years old, Group L: 36.1+/-6.2 years old). There was no significant group difference in sex ratio or number of years of education. The mean age of onset of Group L was significantly lower than that of Group S (Group S; 25.5+/-10.2 years old, Group L; 15.3+/-7.1 years old). The total Y-BOCS mean score and MOCI score showed no group differences. These two groups showed similar clinical characteristics such as the severity of OC symptom, OC subtypes, and comorbid depression. Group S, however, demonstrated significantly more obsession with the need for correction. Group L had significantly higher levels of anxiety and compulsion. There were also no group differences in the mean HDRS or STAI scores. As a result, compared to Group S, Group L showed significant attention deficit in the Stroop test and the WMS-R though other neuropsychological dysfunctions such as intellectual level, executive function, verbal memory, and nonverbal memory were found in this group. Concerning treatment response, Group L showed little improvement by pharmacotherapy. Behavior therapy brought significant improvement to all patients of both groups. Long duration of the illness might cause attention deficit and a lowered pharmaceutical response in OCD patients.     

Duration of untreated psychosis and neuropsychological function in first episode psychosis

PURPOSE: We investigated whether duration of untreated psychosis (DUP) prior to first presentation was associated with cognitive function in first episode psychosis (FEP) subjects. We predicted that longer DUP would be associated with greater neurocognitive impairment. METHOD: 180 subjects with schizophrenia (and 93 subjects with Other Psychoses) performed a neurocognitive battery assessing IQ, verbal learning, working memory, visual learning and speed of processing. DUP was defined as the number of days between first onset of psychotic symptoms and first contact with psychiatric services. RESULTS: Longer DUP was associated with impaired performance in verbal IQ (p=0.04), verbal learning (p=0.02), and verbal working memory (p=0.04) in FEP subjects with schizophrenia. These associations remained significant for verbal IQ when scores were corrected for age, gender, educational level and ethnicity. CONCLUSIONS: Longer DUP is associated with poorer neurocognitive ability in schizophrenia subjects at time of first presentation. Since this was a cross-sectional study we can not tell whether longer DUP was a cause or a consequence of the poorer performance.