Modulation of human extrastriate visual processing by selective attention to colours and words.

The present study investigated the effect of visual selective attention upon neural processing within functionally specialized regions of the human extrastriate visual cortex. Field potentials were recorded directly from the inferior surface of the temporal lobes in subjects with epilepsy. The experimental task required subjects to focus attention on words from one of two competing texts.

The DCC protein -- neural development and the malignant process.

The deleted in colorectal cancer (DCC) gene encodes a neural cell adhesion family molecule that was originally identified as a candidate tumor suppressor target of 18q allelic loss in colorectal cancer. However, the importance of the DCC protein has been most clearly demonstrated in neural development. Mutational and subsequent biochemical studies in C.

Trauma-related dissociative states and long-term psychopathology in posttraumatic stress disorder.

Dissociative responses to trauma have been hypothesized to be associated with long-term increases in psychopathology. The purpose of this study was to examine dissociative responses to premilitary, combat-related and postmilitary traumatic events and long-term psychopathology in Vietnam combat veterans with (n = 34) and without (n = 28) posttraumatic stress disorder (PTSD). PTSD patients reported higher levels of dissociative states at the time of combat-related traumatic events than non-PTSD patients.

Social skills at work. Deficits and predictors of improvement in schizophrenia.

While the impact of social learning programs upon social deficits in schizophrenia has been widely studied, less is understood about which patients have the poorest social skills, and among those which patients have deficits most refractory to rehabilitation. To explore these questions, this study compared the symptom levels and performance on neuropsychological testing of 91 subjects with impaired and unimpaired social skills enrolled in a vocational rehabilitation program. After 10 weeks of rehabilitation and a supportive group treatment, social skills among a subsample of 41 subjects with initially impaired social skills were reassessed.

Myelodysplasia. The clinical spectrum of 51 patients.

Background: Over a 15 year period, the authors followed 51 male patients with myelodysplastic syndromes whose clinical findings, laboratory data, and evolution demonstrated a wide spectrum of disease.

Methods: The following characteristics were assessed: age at diagnosis, risk factors, clinical presentation, laboratory features, category of myelodysplasia, leukemic conversion, and overall survival.

Results: The clinical manifestations included hemolytic episodes in two patients, antibody-mediated thrombopenia in one, marked marrow fibrosis in two; thrombocytosis in three, and simultaneous lymphoproliferative disorders in two.

Differences in laser-induced autofluorescence between adenomatous and hyperplastic polyps and normal colonic mucosa by confocal microscopy.

Laser-induced autofluorescence has been used to discriminate normal from adenomatous colonic mucosa. However, few studies to date have studied the origin of colonic autofluorescence. Using confocal microscopy (excitation wavelength 488 nm), we have shown that autofluorescence at this wavelength is present predominantly in the lamina propria of normal mucosa but in the epithelium in adenomatous and hyperplastic polyps.

Negative symptoms and vocational impairment in schizophrenia: repeated measurements of work performance over six months.

Interest in negative symptoms as a dimension of schizophrenia has grown dramatically in the last decade. One hypothesized correlate of negative symptoms that has received less attention is deteriorated work function. To address this issue, this study compared biweekly measurements of work performance for 21 patients with prominent negative symptom and 29 patients without prominent negative symptoms enrolled in a 26-week supported work program.

Relationship of positive and negative symptoms to cocaine abuse in schizophrenia.

The prevalence of cocaine abuse by patients with schizophrenia has led researchers to investigate features of the disorder correlated with abuse. Although abuse has been found to be more common among patients with a diagnosis of paranoid subtype and a history of earlier and more frequent hospitalizations, it is unclear if it is related to any particular pattern of negative or positive symptoms. This study examines the severity of positive and negative symptoms for patients with and without histories of cocaine abuse.

The mastomys gastric carcinoid: aspects of enterochromaffin-like cell function.

The mastomys rodent exhibits a genetic propensity to develop gastric carcinoid tumors. Utilizing acid inhibitory pharmacotherapy (histamine-2 receptor antagonists and proton pump inhibitors), we have demonstrated transformation from normal to neoplastic enterochromaffin-like (ECL) cells in a well-defined fashion over a period of 4 months. In addition, we have demonstrated inhibition of tumor growth with either somatostatin or histamine-1 receptor antagonists (terfenadine and cyproheptadine).

Noradrenergic neuronal dysregulation in panic disorder: the effects of intravenous yohimbine and clonidine in panic disorder patients.

In order to evaluate possible abnormal noradrenergic neuronal functional regulation in patients with panic disorder, the behavioral, biochemical and cardiovascular effects of intravenous yohimbine (0.4 mg/kg) and clonidine (2 micrograms/kg) were determined in 15 healthy subjects and 38 patients with panic disorder. A subgroup of 24 panic disorder patients were observed to experience yohimbine-induced panic attacks and had larger yohimbine-induced increases in plasma 3-methoxy-4-hydroxyphenylglycol (MHPG) than healthy subjects and other panic disorder patients.

Stages of change for smoking cessation among former problem drinkers: a cross-sectional analysis.

Recent research suggests that problem drinkers are less successful in quitting smoking. Stages of change, decisional balance, and self-efficacy measures were used to assess readiness for smoking cessation in a cross-sectional sample of former problem drinkers who were current smokers. As was expected, a very high percentage of recovering problem drinkers had been or currently were regular smokers.

Characteristics of panic attack subtypes: assessment of spontaneous panic, situational panic, sleep panic, and limited symptom attacks.

We report the analyses of daily journal descriptions of 790 self-defined panic attacks from 59 patients meeting DSM-III criteria for panic disorder or agoraphobia with panic attacks. The DSM-III-R specified symptoms occurred with frequencies ranging from choking (17% of attacks) to palpitations (63% of attacks). The mean weekly panic attack severity correlated significantly with the number of symptoms per attack, but not their weekly frequency.

Murine peritoneal macrophage gangliosides inhibit lymphocyte proliferation.

Gangliosides have been shown to act as immunoregulatory agents by altering proliferative responses of lymphocytes to both antigens and mitogens. Most early studies have utilized brain gangliosides and have required high concentrations. The role of endogenous gangliosides from macrophages has remained unexplored.

Localization of the cystic fibrosis transmembrane conductance regulator in pancreas.

Cystic fibrosis (CF) is characterized by an abnormality in cAMP-regulated chloride transport that results from a primary defect in the protein product of the CF gene, the CF transmembrane conductance regulator (CFTR). In this report, antibodies against CFTR peptides were used to localize the CFTR protein in human pancreas. An affinity purified antibody (alpha-1468) raised against a synthetic CFTR peptide identified a 155-170-kD protein on immunoblot.

Propranolol in the prevention of the first hemorrhage from esophagogastric varices: A multicenter, randomized clinical trial. The Boston-New Haven-Barcelona Portal Hypertension Study Group.

To assess the effectiveness of propranolol in the prevention of initial variceal hemorrhage, a double-blind, randomized trial was carried out in three centers. Patients with cirrhosis (78% alcoholic), hepatic venous pressure gradients greater than 12 mm Hg and endoscopically proven esophageal varices were randomly assigned to propranolol (51 patients) or placebo (51 patients). Of the 102 patients, 58% were Child's class A, 34% were Child's class B and 8% were Child's class C.

The straight radial-antecubital PTFE angio-access graft in an era of high-flux dialysis.

Straight radial-antecubital polytetrafluoroethylene (PTFE) grafts were placed in 10 older (greater than 55 years) male patients with significant intercurrent diseases who were considered candidates for high-flux dialysis. Graft patency was 90% at 6 months, and suitable flow for high-flux dialysis (greater than 400 mL/minute) could be achieved with all grafts. Shorter dialysis times with no major cardiovascular, hemodynamic, or extremity complications were achieved with this mode of therapy.

Immunoaffinity purification of parathyroid hormone-related protein from bovine milk and human keratinocyte-conditioned medium.

Parathyroid hormone-related proteins (PRHrP) are a novel family of proteins that appear to be responsible for humoral hypercalcemia of malignancy. Although PTHrP derived from human tumors have been purified and their N-terminal amino acid sequence determined, and although the structure of the PTHrP gene and its alternatively spliced mRNA transcripts have been defined, the secretory and circulating form(s) of the protein are unknown. Purification of PTHrP in the past has been difficult, requiring multiple chromatographic steps and months or years to complete.

Interspecies comparison of renal cortical receptors for parathyroid hormone and parathyroid hormone-related protein.

Parathyroid hormone (PTH) and PTH-related proteins (PTHrP) interact with a common receptor in rat bone cells and in canine renal membranes with similar affinity, but PTHrP are substantially less potent than PTH in stimulating adenylate cyclase in canine renal membranes; in contrast, PTH and PTHrP are equipotent in stimulating adenylate cyclase in rat bone cells. This discrepancy has been largely viewed as reflecting differences in the relative efficiency of signal transduction of PTHrP between bone and kidney assay systems. To test the alternative (but not mutually exclusive) hypothesis that these differences could reflect interspecies differences in PTH receptors, we have characterized the bioactivity of amino-terminal PTHrP and PTH in rat and human renal cortical membranes (RCM) and compared them to results we previously reported in canine RCM.

Intracellular activation of digestive zymogens in rat pancreatic acini. Stimulation by high doses of cholecystokinin.

The mechanism by which digestive zymogens become activated during acute pancreatitis remains poorly understood. Given the ability for cholecystokinin (CCK) to induce pancreatitis in vivo, the effects of high dose CCK on preparations of isolated pancreatic acini were examined. Using an immunologic technique for the detection of zymogen activation, CCK was found to stimulate the conversion of procarboxypeptidase A1 to a 35-kD form having the same net charge and electrophoretic mobility as purified recombinant carboxypeptidase A1.

Clinical review 16: Parathyroid hormone-related proteins: coming of age in the 1990s.

The last 3 yr have yielded a fertile harvest of new information on the HHM clinical syndrome and on the novel peptide hormone family responsible for the syndrome. Whereas the clinical riddle enshrouding the HHM syndrome first posed in the early 1940s appears to have been largely solved, a whole new field, concerning the physiological role(s) of PTHRP has opened. The field has evolved rapidly and provides an example of fruitful clinical investigation: the original problem was a clinical one (the HHM syndrome); understanding the clinical disorder led to pursuit of the problem in the laboratory (adenylate cyclase assays, protein purification, molecular cloning, PTHRP synthesis); and observations made in the laboratory have rapidly yielded clinical fruits (PTHRP immunoassays) and opened a new window on normal physiology.

Recall and stem-completion priming have different electrophysiological correlates and are modified differentially by directed forgetting.

The notion that different aspects of memory are assessed by explicit and implicit memory tests was supported by behavioral and electrophysiological results. In a study-test procedure, 24 subjects were instructed to remember some words and to forget other words. Free recall and cued recall were better for words associated with the remember instruction, whereas directed forgetting did not influence stem completion (an implicit memory test).

Usefulness of verapamil for congestive heart failure associated with abnormal left ventricular diastolic filling and normal left ventricular systolic performance.

Normal left ventricular systolic performance with impaired left ventricular diastolic filling may be present in a substantial number of patients with congestive heart failure (CHF). To evaluate the effect of oral verapamil in this subset, 20 men (mean age 68 +/- 5 years) with CHF, intact left ventricular function (ejection fraction greater than 45%) and abnormal diastolic filling (peak filling rate less than 2.5 end-diastolic volumes per second [edv/s]) were studied in a placebo-controlled, double-blind 5-week crossover trial.

Effects of mitogens and other agents on rat mesangial cell proliferation, pH, and Ca2+.

We investigated effects of various agents on proliferation, intracellular pH (pHi), and intracellular calcium [( Ca2+]i) of rat mesangial cells (MCs) in early passages (2-5). Serum-starved MCs incubated in HCO3- were exposed to one of the following: fetal calf serum (FCS), serotonin, angiotensin II (ANG II), arginine vasopressin (AVP), bombesin (Bom), bradykinin (BK), epidermal growth factor (EGF), epinephrine (Epi), interleukin 1 (IL-1), norepinephrine (NE), neuropeptide Y, oxytocin, substance P (SP), platelet-derived growth factor, or 12-O-tetradecanoylphorbol-13-acetate (TPA). We assessed DNA synthesis from [3H]thymidine uptake during exposure to test agent.

Laser-induced fluorescence spectroscopy of human colonic mucosa. Detection of adenomatous transformation.

To evaluate the potential of laser-induced fluorescence spectroscopy for the detection of premalignant lesions of the gastrointestinal tract, the hypothesis that adenomatous transformation of colonic mucosa results in an alteration of laser-induced fluorescence that enables its differentiation from normal or hyperplastic tissue was tested. A fiberoptic catheter coupled to a helium-cadmium laser (325 nm) and an optical multichannel analyzer were used to obtain fluorescence spectra (350-600 nm) from 35 normal colonic specimens and 35 resected adenomatous polyps. A score based on six wavelengths was derived by stepwise multivariate linear regression analysis of the spectra.