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D Bernstein

Publications and source records attributed to D Bernstein.

At least 19 recordsLinked to original sources
PubMed1996

Cardiovascular regulation in mice lacking alpha2-adrenergic receptor subtypes b and c.

alpha2-Adrenergic receptors (alpha2ARs) are essential components of the neural circuitry regulating cardiovascular function. The role of specific alpha2AR subtypes (alpha2a, alpha2b, and alpha2c) was characterized with hemodynamic measurements obtained from strains of genetically engineered mice deficient in either alpha2b or alpha2c receptors. Stimulation of alpha2b receptors in vascular smooth muscle produced hypertension and counteracted the clinically beneficial hypotensive effect of stimulating alpha2a receptors in the central nervous system. There were no hemodynamic effects produced by disruption of the alpha2c subtype. These results provide evidence for the clinical efficacy of more subtype-selective alpha2AR drugs.

Adrenergic alpha-Agonists↗
PubMed1996

Targeted disruption of the mouse beta1-adrenergic receptor gene: developmental and cardiovascular effects.

At least three distinct beta-adrenergic receptor (beta-AR) subtypes exist in mammals. These receptors modulate a wide variety of processes, from development and behavior, to cardiac function, metabolism, and smooth muscle tone. To understand the roles that individual beta-AR subtypes play in these processes, we have used the technique of gene targeting to create homozygous beta 1-AR null mutants (beta 1-AR -/-) in mice. The majority of beta 1-AR -/- mice die prenatally, and the penetrance of lethality shows strain dependence. Beta l-AR -/- mice that do survive to adulthood appear normal, but lack the chronotropic and inotropic responses seen in wild-type mice when beta-AR agonists such as isoproterenol are administered. Moreover, this lack of responsiveness is accompanied by markedly reduced stimulation of adenylate cyclase in cardiac membranes from beta 1-AR -/- mice. These findings occur despite persistent cardiac beta 2-AR expression, demonstrating the importance of beta 1-ARs for proper mouse development and cardiac function, while highlighting functional differences between beta-AR subtypes.

Adenylyl Cyclases↗
PubMed1996

Evaluation of household dust mite exposure and levels of specific IgE and IgG antibodies in asthmatic patients enrolled in a trial of immunotherapy.

BACKGROUND: Monitoring the response to immunotherapy entails understanding exposure to relevant allergens. For the major indoor allergens, this requires sampling of dust from the patient's house. The objectives of this study were to measure indoor allergen levels during a controlled trial of dust mite immunotherapy for asthma and to relate these results to serum antibody levels. METHODS: Eighty-eight asthmatic patients with mite allergy from seven geographic areas in the United States were enrolled in and completed a course of immunotherapy with Dermatophagoides extract or placebo control. Sensitization was evaluated by quantitative measurements of IgG and IgE antibodies. Dust samples were assayed for group I mite (Der p 1 and Der f 1), cat (Fel d 1), and cockroach (Bla g 1) allergens by monoclonal antibody-based ELISA. RESULTS: Over the 4 years of the study, each of the houses had at least one sample that contained more than 2 micrograms of group I mite allergen per gram of dust. Mean mite allergen levels, however, varied over a wide range, from 0.2 microgram/gm or less to more than 50 micrograms/gm. IgE antibodies to mite were present in sera from 78% of the patients, whereas IgE antibodies to cat and cockroach allergens were found in sera from 34% and 11% of patients, respectively. Sixty-four percent of the patients had exposure and sensitization to mite, whereas the comparable figure for each of the other allergens was 5%. CONCLUSIONS: Examination of the results suggested that allergen exposure, relative to a trial of immunotherapy, could be expressed as (1) the maximum level found in the house, (2) the percentage of sites having greater than 2 micrograms/gm, or (3) the mean value at the site with the maximum level. This report provides a background for evaluating the clinical results of immunotherapy in these patients and a model for the way in which sensitization and exposure should be monitored in studies of this kind.

Adolescent↗
PubMed1996

Admission criteria for inpatient substance abuse/dependence rehabilitation: implications for managed care.

In view of recent trends toward the replacement of traditional inpatient rehabilitation programs with nonresidential services, we examined the extent to which patients currently admitted to inpatient rehabilitation for alcohol or drug abuse/dependence met published criteria suggesting a preferential need for inpatient or residential care. Over 90% of almost 300 veterans with a primary DSM-III R diagnosis of alcohol or substance abuse/dependence, admitted to six New York Metropolitan Area Veterans Administration Medical Centers for inpatient rehabilitation, met at least one criterion dimension considered indicative of a need for such services, with over two-thirds meeting two or more dimensions. These findings suggest a continuing need for initial primary inpatient or residential rehabilitation for such patients.

Adult↗
PubMed1996

Malignancy in Crohn's disease.

The risk for the development of malignancy in Crohn's disease is not as well defined as it is with ulcerative colitis. The risk for the development of small bowel adenocarcinoma is greater in patients with Crohn's disease than in the general population although the magnitude of this increased risk is unclear. Risk factors associated with the development of small bowel carcinoma in Crohn's disease include male sex, duration of disease, associated fistulous disease, and the presence of surgically excluded loops of bowel. Crohn's colitis has been associated with an increased risk of colorectal carcinoma in patients with long-standing colitis, strictures, fistulae, and right-sided colonic disease. Secondary gastrointestinal carcinomas are rare in Crohn's disease. This article reviews the current literature regarding the association of various malignancies in Crohn's disease. Although concentrating on population based and case-control studies, it includes referral center studies as well as case reports.

Case-Control Studies↗
PubMed1995

Arterial switch and resection of hepatic hemangioendothelioma.

We report on the management of a neonate undergoing arterial switch for transposition of the great arteries and concomitant resection of a hepatic infantile hemangioendothelioma. A preoperative aortogram demonstrated the arterial supply of the hepatic hemangioendothelioma. Pulmonary artery hypertension and myocardial ischemia were noted after separation from cardiopulmonary bypass. Resection of the hepatic malformation produced an immediate reduction in pulmonary hypertension and resolution of the myocardial ischemia. The patient had an uneventful postoperative recovery.

Female↗
PubMed1995

Cardiac transplantation for hypertrophic cardiomyopathy associated with Sengers syndrome.

Sengers' syndrome is a rare condition consisting of congenital cataracts, mitochondrial myopathy, and hypertrophic cardiomyopathy. The syndrome is transmitted in an autosomal recessive pattern. Progressive cardiac failure is the cause of death in most patients. This report describes cardiac transplantation for the treatment of the cardiomyopathy associated with Sengers' syndrome.

Cardiomyopathy, Hypertrophic↗
PubMed1995

Development and testing of monoclonal antibody-based rapid immunodiagnostic test kits for direct detection of Vibrio cholerae O139 synonym Bengal.

We report on the development and testing of two monoclonal antibody-based rapid immunodiagnostic test kits, BengalScreen, a coagglutination test, and Bengal DFA, a direct fluorescent-antibody test, for direct detection of Vibrio cholerae O139 synonym Bengal in clinical and environmental specimens. The BengalScreen test requires less than 5 min to complete and can be used in the field. Bengal DFA, being more sensitive than BengalScreen, requires only one reagent and less than 20 min for detection and enumeration of V. cholerae O139 synonym Bengal. In tests for specificity, all 40 strains of V. cholerae O139 reacted with both test kits, whereas 157 strains of heterologous species examined did not, yielding 100% specificity in this study. A field trial was conducted in with both BengalScreen and Bengal DFA, and the results were compared with those obtained by conventional culture methods. BengalScreen demonstrated a sensitivity of 95%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 94%. Results obtained by Bengal DFA, on the other hand, were 100% sensitive and 100% specific and yielded 100% positive and negative predictive values compared with culture methods. In a second evaluation, 93 stool specimens from Mexico that were negative for V. cholerae O139 by culture were also tested with both the BengalScreen and Bengal DFA kits. None of the 93 specimens were positive for V. cholerae O139 by both tests. A concentration method was optimized for screening of environmental water samples for V. cholerae O139 synonym Bengal with rapid test kits. BengalScreen results were unequivocally positive when water samples contained at least 2.0 x 10(3) CFU/ml, whereas Bengal DFA demonstrated an unequivocally positive reaction when the water sample contained at least 1.5 x 10(2) CFU/ml. When Bengal DFA was compared with conventional culture methods for enumeration of V. cholerae O139 synonym Bengal organisms, no difference was observed.

Agglutination Tests↗
PubMed1995

Initial reliability and validity of the childhood trauma interview: a new multidimensional measure of childhood interpersonal trauma.

OBJECTIVE: The Childhood Trauma Interview, a new instrument for brief and comprehensive retrospective assessment of childhood interpersonal trauma, is presented with initial evidence of its reliability and validity. METHOD: Drug- or alcohol-dependent patients (N = 220) were given the Childhood Trauma Interview and a questionnaire measure of child abuse, the Childhood Trauma Questionnaire. Convergent and discriminant validity for the Childhood Trauma Interview were tested by comparing correlations between analogous and nonanalogous trauma scales to those of the Childhood Trauma Questionnaire. RESULTS: Interrater reliability for the majority of trauma dimensions measured by the Childhood Trauma Interview was very high (63% had intraclass correlations above 0.90). Principal-components analysis yielded six rotated factors that accounted for 74% of the variance among scores: separations and losses, physical neglect, emotional abuse or assault, physical abuse or assault, witnessing violence, and sexual abuse or assault. Since these six factors exactly represented the areas that the interview was designed to assess, the construct validity of the Childhood Trauma Interview was supported. Without exception, convergent correlations were significantly higher than discriminant correlations, and convergence was improved when multidimensional variables from the Childhood Trauma Interview and their interactions were regressed onto Childhood Trauma Questionnaire scores. CONCLUSIONS: These initial findings suggest that the Childhood Trauma Interview is a reliable and valid method for brief assessment of multiple dimensions of six types of childhood interpersonal trauma.

Adult↗
PubMed1995

Colchicine and cytochalasin B enhance cyclic AMP accumulation via postreceptor actions.

The role of cytoskeletal microtubules and microfilaments in modulating cAMP generation in S49 lymphoma cells was investigated using the agents colchicine and cytochalasin B, respectively, which are known to disrupt these structures. A 1-hr pretreatment of S49 cells with 10 microM colchicine typically enhanced maximal isoproterenol-(beta-adrenergic receptor) stimulated cAMP accumulation by 100%, whereas cytochalasin B increased isoproterenol-stimulated cAMP by 30%. The combination of colchicine and cytochalasin B synergistically enhanced agonist-stimulated cAMP to 225% over control values. A synergistic increase in cAMP accumulation was also observed in cells treated with the agonist prostaglandin E1 or cholera toxin (which activates the stimulatory guanine nucleotide regulatory (Gs) protein). Colchicine and cytochalasin B did not ablate the inhibitory effects of somatostatin or the stimulatory effect of pertussis toxin treatment on beta-receptor-stimulated cAMP accumulation, indicating that these cytoskeletal disrupting agents do not enhance responsiveness in S49 cells via alterations in the inhibitory guanine nucleotide regulatory protein pathway. Moreover, colchicine, but not cytochalasin B treatment, enhances expression of isoproterenol-promoted 3H-forskolin binding in intact cells (a measure of Gs/adenylyl cyclase coupling). Thus, colchicine and cytochalasin B appear to enhance signaling in the Gs/adenylyl cyclase pathway by alterations of components distal to hormone receptors, most likely at the Gs protein and/or via cAMP generation. These results imply that microtubules and microfilaments can interact in the regulation of this pathway and that increases in cellular cAMP may contribute to the action of drugs that alter function of these cytoskeletal elements.

Adenylyl Cyclases↗
PubMed1995

Diagnostic laparoscopy: a 5-year experience in a hepatology training program.

Diagnostic laparoscopy continues to have a role in the evaluation and diagnosis of acute and chronic liver diseases, primary and metastatic liver tumors, and peritoneal diseases. We retrospectively reviewed the records of 1794 diagnostic laparoscopies performed at our institution from 1987 to 1992 to identify the indications, results, and safety of this procedure in our training program. A definitive diagnosis was made in 91% of cases with biopsy performed in 93%. Chronic liver disease was evaluated in 890 patients, and a diagnosis was made in 98%. Four hundred thirty-seven patients were evaluated for suspected primary or metastatic carcinoma, and a diagnosis was made in 85%. Ascites was evaluated in 73 patients, and a diagnosis was made in 82%. One-hundred sixty-four patients were evaluated for abnormal liver function tests, and a diagnosis was made in 91%. HIV-related liver function test abnormalities were evaluated in 67 patients, and a diagnosis was made in 81%. One hundred sixty-three patients underwent diagnostic laparoscopy for the evaluation of hepatomegaly, splenomegaly, unexplained portal hypertension, fever of unknown origin, and cholestasis, and a diagnosis was made in 74% of cases. Eight major complications (including abdominal viscus perforation, hemobilia, splenic laceration, bleeding) and thirty-one minor complications were seen. Our findings confirm that diagnostic laparoscopy is a safe and valuable procedure in the evaluation of chronic liver disease.

Chronic Disease↗
PubMed1994

Cholera DFA: an improved direct fluorescent monoclonal antibody staining kit for rapid detection and enumeration of Vibrio cholerae O1.

An improved fluorescent monoclonal antibody staining kit, Cholera DFA, for direct detection and enumeration of Vibrio cholerae O1 has been developed, employing a highly specific anti-A antigen monoclonal antibody, COLTA, labeled with fluorescein isothiocyanate (FITC). An optimized quantity of anti-photobleaching agent is used in a glycerol mounting medium to retard the rapid fading of immunofluorescent stained cells during fluorescent microscopy, thus enabling prolonged inspection of individual fields, as well as improved photographic recording of results without loss of fluorescence intensity. When tested for specificity, all 30 strains of V. cholerae O1 reacted with Cholera DFA, whereas 100 heterologous species examined did not, yielding 100% specificity for all strains examined in this study. A field trial was conducted in Bangladesh, employing Cholera DFA and the results were compared with those obtained by conventional culture methods. Of 44 diarrheal stool specimens tested, Cholera DFA was positive for V. cholerae O1 in all culture-positive stool specimens and negative for all culture-negative stool specimens. The procedure is sensitive and highly specific, as well as simple, i.e., less complex than the indirect fluorescent assay, requiring only one reagent and less than 30 min to complete the staining process, while retarding rapid fading that often occurs with fluorescent microscopy.

Antibodies, Monoclonal↗
PubMed1994

Ureteric stent in severe hydronephrosis of pregnancy.

Eleven women (12 pregnancies) were included in the study. A double-pigtail ureteric stent was passed under cytoscopic vision in 8 patients. The mean gestational age on insertion of the stents was 29 weeks (range, 25-35 weeks). Delivery took place at a mean of 39 weeks (range, 35-41 weeks). Stents remained in situ for a mean of 9 weeks (range, 6-14 weeks) before delivery and were removed 4-5 weeks postpartum. Double pigtail ureteric stents did not expose the women to infection. Renal function tests remained within the normal limits. Ureteric stent is an effective method for internal drainage of severe hydronephrosis during pregnancy.

Adult↗
PubMed1994

Carnitine palmitoyl transferase deficiency in pregnancy--a case report.

Carnitine palmitoyl transferase deficiency is one of the mitochondrial myopathies characterized by weakness, exercise intolerance, and myoglobinuria after prolonged exercise. This is the first case report concerning a pregnant woman with carnitine palmitoyl transferase deficiency that was also proved by the decrease of carnitine palmitoyl transferase activity in uterine myometrium biopsy.

Adult↗
PubMed1994

Pediatric cardiac transplantation. The Stanford experience.

BACKGROUND: Cardiac transplantation for children with endstage heart disease has become an accepted form of therapy and is being practiced with increasing frequency and improving short-term outcome. METHODS AND RESULTS: To assess the medium-term outcome of pediatric cardiac transplantation, we analyzed our experience with 72 patients under the age of 18 (range, 0.1 to 17.7 years; mean, 9 +/- 6.4 [SD]) who underwent orthotopic cardiac transplantation at Stanford University between 1977 and 1993. There were 38 male and 34 female patients. Preoperative diagnoses included congenital heart disease in 24 (33%), idiopathic cardiomyopathy in 27 (37%), viral cardiomyopathy in 12 (17%), and familial cardiomyopathy in 7 (10%) patients. Immunosuppressive management has evolved over time and has included a tapering schedule of steroids, azathioprine, rabbit antithymocyte globulin, cyclosporine in all patients after 1980, and induction with OKT3 since 1987. Operative mortality rate was 12.5 +/- 4.0% (mean +/- 70% confidence intervals). Actuarial survival estimates at 1, 5, and 10 years are 75 +/- 7.1%, 60 +/- 6.4%, and 50 +/- 8.1% (mean +/- 1 SEM), respectively. Causes of death included infection in 8 (28% of deaths), rejection in 7 (24%), graft coronary disease in 5 (17%), pulmonary hypertension in 4 (14%), and nonspecific graft failure in 2 (7%) patients. Survival rates were similar for patients over and those under age 10 years (including the infant cohort of 18 patients transplanted since 1986). Currently, there are 43 patients alive, all in New York Heart Association functional class I. Only 22 +/- 5.6% of patients were free of rejection at 1 year, but 86 +/- 5.4% were free of rejection-related death at 10 years. At 1 year, only 37 +/- 6% of patients were free from any infection, but 88 +/- 4.2% remained free of infection-related death at 5 years. Actuarial freedom from graft coronary artery disease (angiographic or autopsy proven) was 85 +/- 6.6% at 5 years and from coronary artery disease-related death was 91 +/- 4.7%. CONCLUSIONS: These data demonstrate satisfactory medium-term outcome of cardiac transplantation in selected pediatric patients with end-stage heart disease, but further progress is necessary to more effectively control rejection, infection, and graft coronary disease.

Actuarial Analysis↗