Reduced event-related current density in the anterior cingulate cortex in schizophrenia.

There is good evidence from neuroanatomic postmortem and functional imaging studies that dysfunction of the anterior cingulate cortex plays a prominent role in the pathophysiology of schizophrenia. So far, no electrophysiological localization study has been performed to investigate this deficit. We investigated 18 drug-free schizophrenic patients and 25 normal subjects with an auditory choice reaction task and measured event-related activity with 19 electrodes.

Cost-effectiveness of trachoma control measures: comparing targeted household treatment and mass treatment of children.

Objective: The present study compares the cost-effectiveness of targeted household treatment and mass treatment of children in the most westerly part of Nepal.

Methods: Effectiveness was measured as the percentage point change in the prevalence of trachoma. Resource measures included personnel time required for treatment, transportation, the time that study subjects had to wait to receive treatment, and the quantity of azithromycin used.

Comparison of two azithromycin distribution strategies for controlling trachoma in Nepal.

Objective: The study compares the effectiveness of two strategies for distributing azithromycin in an area with mild-to-moderate active trachoma in Nepal.

Methods: The two strategies investigated were the use of azithromycin for 1) mass treatment of all children, or 2) targeted treatment of only those children who were found to be clinically active, as well as all members of their household.

Findings: Mass treatment of children was slightly more effective in terms of decreasing the prevalence of clinically active trachoma (estimated by clinical examination) and of chlamydial infection (estimated by DNA amplification tests), although neither result was statistically significant.

Spatial reference memory and neocortical neurochemistry vary with the estrous cycle in C57BL/6 mice.

Estrous cycle-related variations of spatial reference memory and neurochemistry in intact female mice were examined. Spatial reference memory was tested in cycling females, ovariectomized (OVX) females, and males by using a 1-day water maze protocol. Choline acetyltransferase (ChAT) and glutamic acid decarboxylase (GAD) activities were measured in the hippocampus and neocortex.

Inhibition of N-myc expression and induction of apoptosis by iron chelation in human neuroblastoma cells.

Neuroblastoma is the second most common solid malignancy of childhood. Enhanced expression of the amplified N-myc gene in the tumor cells may be associated with poor patient prognosis and may contribute to tumor development and progression. The use of deferoxamine mesylate (DFO), an iron chelator, to treat neuroblastoma is being investigated in national clinical studies.

Managed care and community health centers.

This study has two objectives: (1) to examine the relationship between the involvement of community health centers (CHCs) in managed care and various center characteristics, including patient, provider, services, and financial characteristics, that are critically linked with the fulfillment of their mission and (2) to identify factors significantly associated with CHCs' involvement in managed care. Regarding the first objective, the study indicates that CHCs involved in managed care have more diversified sources of revenue and depend less on grant funding than other CHCs, and they serve a significantly smaller proportion of uninsured and homeless patients. Involvement in managed care is also associated with greater financial vulnerability, reflected in higher costs and net revenue deficits.

Cholinergic basal forebrain is critical for social transmission of food preferences.

Studies using selective lesions of basal forebrain cholinergic neurons suggest that these neurons play a role in attentional processing, but not learning and memory. However, the tests of learning and memory used thus far have been restricted largely to spatial tasks. In the present study, we examined whether the cholinergic basal forebrain plays a role in a form of nonspatial associative memory, the social transmission of food preferences.

Mice are not little rats: species differences in a one-day water maze task.

The present study examined species differences in spatial and non-spatial memory in the Morris water maze. Male Wistar rats and C57BL/6 mice were tested in a one-day water maze task in which spatial learning, retention, and non-spatial learning were assessed within 3 h. Rats and mice appeared to use different strategies for locating the hidden escape platform.

Genital cutaneous Crohn disease: two cases with unusual clinical and histopathologic features in young men.

Cutaneous Crohn disease, sometimes called metastatic Crohn disease or Crohn disease with cutaneous involvement, is a rare complication of Crohn disease in which granulomatous lesions involve skin separated from gastrointestinal lesions by normal tissue. We report two cases of cutaneous Crohn disease presenting in young males with erythematous, nontender swelling of the scrotum. One of the young males presented erythematous, nontender swelling of the penis as well.

Frontal dysfunction in schizophrenia--a new electrophysiological classifier for research and clinical applications.

We determined whether schizophrenic patients can be reliably classified with electrophysiological tools. We developed a fully computerized classifier based on 5 minutes of EEG recording during an acoustical choice reaction time task (AMDP-module IV). We included factorized variables from the frequency domain and evoked potentials (N100/P200-complex) from central and frontal electrodes, which were preprocessed in a sample of 150 normal subjects prior to classification.

The effects of acid on bone.

Metabolic acidosis induces calcium efflux from bone and in the process buffers the additional hydrogen ions. Initially metabolic acidosis stimulates physicochemical mineral dissolution and then cell-mediated bone resorption. Acidosis increases activity of the bone resorbing cells, the osteoclasts, and decreases activity of the bone forming cells, the osteoblasts.

Economic burden of hospitalizations for preterm labor in the United States.

Objective: To determine patient factors associated with hospital care costs for preterm labor and to develop a clinically applicable cost model for evaluating economic consequences of interventions to reduce preterm-labor hospitalizations.

Methods: Maryland state hospital discharge data from 1993-1996 were used to identify hospitalizations for preterm labor without delivery and preterm labor with early delivery. Median regression was used to determine the association between patient factors and hospital care costs in Maryland and to develop a model to estimate hospital care costs nationally.

Schizophrenia: reduced signal-to-noise ratio and impaired phase-locking during information processing.

Objective: This study was performed in order to clarify the mechanisms which underlie the reduced signal-to-noise of event-related potentials in schizophrenic patients. Specifically, we wanted to find out, whether it is reduced activation and/or synchronization (phase-locking) in specific frequency bands of the ongoing EEG which is related to the decreased signal amplitude and signal-to-noise ratio in schizophrenics.

Methods: We investigated 41 unmedicated schizophrenics (10 of them drug-naïve) and compared them with healthy control subjects (n = 233) as well as unmedicated subjects with schizotypal personality (n = 21), who were considered to be high-risk subjects for schizophrenia, and unmedicated depressive patients (n = 71).

Neonatal 192 IgG-saporin lesions of basal forebrain cholinergic neurons selectively impair response to spatial novelty in adult rats.

The role of the developing cholinergic basal forebrain system on cognitive behaviors was examined in 7 day-old rats by giving lesions with intraventricular injections of 192 IgG-saporin or saline. Rats were subjected to passive avoidance on postnatal days (PND) 22-23, water maze testing on PND 50-60, and a open-field test (in which reactions to spatial and object novelty were measured) on PND 54. Behavioral effects of the lesions were evident only in the open-field test with 5 objects.

Effect kinetics of desmopressin-induced platelet retention in healthy volunteers treated with aspirin or placebo.

Desmopressin is often used for haemostatic treatment in platelet dysfunction, but the effect kinetics of platelet responses and the mechanism of action are poorly known. This study aimed to determine the kinetics of platelet function responses induced by desmopressin in healthy volunteers treated with aspirin or placebo. Another aim was to correlate platelet responses to changes of von Willebrand factor (vWF) in plasma.

The impact of managed care on the existence of equilibrium in health insurance markets.

This study examines the existence of equilibrium in insurance markets when the number of insurance policy attributes is increased (i.e., managed care is introduced).

Reference memory, anxiety and estrous cyclicity in C57BL/6NIA mice are affected by age and sex.

Age-related changes in learning and memory are common in rodents. However, direct comparisons of the effects of aging on learning and memory in both males and females are lacking. The present study examined whether memory deteriorates with increasing age in C57BL/6NIA mice, and whether age-related changes in learning and memory are similar in both sexes.

Effect of the ownership of dialysis facilities on patients' survival and referral for transplantation.

Background: More than 200,000 patients with end-stage renal disease undergo dialysis in the United States each year, about two thirds in for-profit centers. Economic pressures, such as the decline in inflation-adjusted Medicare payments for dialysis, may compromise the quality of care. Facilities may also be reluctant to refer patients to be evaluated for transplantation because of the loss of revenues from dialysis after patients receive transplants.

In vitro metabolic and respiratory acidosis selectively inhibit osteoblastic matrix gene expression.

Clinically, a decrease in blood pH may be due to either a reduction in bicarbonate concentration ([HCO(-)(3)], metabolic acidosis) or an increase in PCO(2) (respiratory acidosis). In mammals, metabolic acidosis induces a far greater increase in urine calcium excretion than respiratory acidosis. In cultured bone, metabolic acidosis induces a marked increase in calcium efflux and a decrease in osteoblastic collagen synthesis, whereas isohydric respiratory acidosis has little effect on either parameter.

Cortical activation, signal-to-noise ratio and stochastic resonance during information processing in man.

Objectives: The goal of this study was to determine the relation between EEG, event-related potentials and information processing as measured by an acoustical choice reaction time task. In particular, we wanted to find out to what extent reaction-time performance is related to the pre-stimulus EEG activity (frequency domain) and the magnitude of signal power as well as noise power (stimulus-uncorrelated activity) after the tones (time domain).

Materials And Methods: For parametrization, EEG-activity was factorized across pre-defined frequency bands and 19 electrode positions, applying spectral power and coherence analysis.

Presynaptic markers of cholinergic function in the rat brain: relationship with age and cognitive status.

The nature of age-related changes in cholinergic function and their relationship to age-related behavioral decline were examined in the present study. Male Fischer-344 rats of four ages (four, 11, 17 and 23 months) were tested in a battery of cognitive tasks. Discrete microdissections of brain areas involved in cognitive function were performed, and activity of choline acetyltransferase and levels of hemicholinium-3 binding were determined to assess the integrity of cholinergic innervation.