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Robert Weiss

Publications and source records attributed to Robert Weiss.

18 recordsLinked to original sources
PubMed2003

Effect of an oral Shiga toxin-binding agent on diarrhea-associated hemolytic uremic syndrome in children: a randomized controlled trial.

CONTEXT: Diarrhea-associated hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure in children. Most cases are caused by an intestinal infection with Shiga toxin-producing strains of Escherichia coli. OBJECTIVE: To determine if administration of an oral agent that binds Shiga toxin could diminish the severity of diarrhea-associated HUS in pediatric patients. DESIGN, SETTING, AND PATIENTS: Multicenter, randomized, double-blind, placebo-controlled clinical trial of 145 children (96 experimental and 49 placebo) aged 6 months to 18 years with diarrhea-associated HUS conducted between July 27, 1997, and April 14, 2001, at 26 tertiary care pediatric nephrology centers in the United States and Canada. Trial included 2 phases, the hospital course for treatment of the acute illness and a 60-day outpatient follow-up period after discharge from the hospital. INTERVENTION: Patients were assigned to receive the binding agent, 500 mg/kg daily, or cornmeal placebo orally for 7 days in a 2:1 randomization scheme. MAIN OUTCOME MEASURES: Combined frequency of death or serious extrarenal events and need for dialysis in the experimental vs placebo group. RESULTS: A total of 62 patients (43%) were male and 123 (85%) were white. The median age of the patients was 4.2 years. Most patients (59%) were transferred from other hospitals to participating sites. The severity of disease at the time of randomization was comparable in the 2 groups. The prevalence of death or serious extrarenal events was 18% and 20% in the experimental and placebo groups, respectively (P =.82). Dialysis was required in 42% of experimental and 39% of placebo groups (P =.86). CONCLUSIONS: Oral therapy with a Shiga toxin-binding agent failed to diminish the severity of disease in pediatric patients with diarrhea-associated HUS.

Administration, Oral↗
PubMed2003

The relationship between nonfasting and fasting lipid measurements in patients with or without type 2 diabetes mellitus receiving treatment with 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors.

BACKGROUND: Studies have confirmed a lack of patient and physician adherence to the revised National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III) guidelines. These guidelines state that lipid panels should be obtained while the patient is in the fasting state. However, this restriction may limit the ordering of these tests and thus decrease the number of patients on drug therapy and the number treated until goal cholesterol levels are reached. Evidence shows that testing in the nonfasting state may not be clinically or significantly different from testing in the fasting state in identifying patients at risk for a future cardiovascular event. OBJECTIVES: The purpose of this study was to determine whether a relationship exists between nonfasting and fasting lipid values in diabetic or nondiabetic patients that will permit the more ready identification of patients who require treatment to meet NCEP ATP III guidelines. A secondary goal was to determine whether diabetic patients who appear to have reached goal cholesterol levels in the fasting state meet those goals when the non-high-density lipoprotein cholesterol (HDL-C) levels are measured in the nonfasting state. METHODS: This observational study was conducted at Androscoggin Cardiology Associates (Auburn, Maine). Patients with hyperlipidemia receiving statin therapy whose doses had not changed for > or =2 months were enrolled. For all patients, nonfasting and fasting lipid panels (total cholesterol, triglycerides [TGs], and HDL-C) were calculated, whereas low-density lipoprotein cholesterol (LDL-C)levels were measured directly. The direct LDL-C method was used to determine the variance of the calculated LDL-C from the actual value. RESULTS: One hundred consecutive hyperlipidemic patients were tested. Patients included 70 men and 30 women, with a mean (SD) age of 66.2 (12.0) years(range, 24-93 years). Eighteen patients had type 2 diabetes mellitus (DM). Non-fasting TG, HDL-C, and LDL-C levels were able to identify almost all patients who did not meet ATP III guidelines in terms of cholesterol levels (95%, 100%, and 95%, respectively). No predictive differences were found, regardless of whether the patients had type 2 DM. For the total population, statistically significant differences were found between calculated nonfasting and fasting measurements for mean (SD)LDL-C levels (90.2 [24.8] mg/dL vs 99.7 [26.1] mg/dL, respectively; P < 0.001). The regression equation was fasting LDL-C = 22.7 + 0.854 x nonfasting LDL-C.A nonfasting LDL-C level >130 mg/dL predicted a fasting LDL-C level >100 mg/dL(95% CI, -12.79 to -6.24), and a nonfasting LDL-C level >130 mg/dL predicted cases of fasting LDL-C level >100 mg/dL (95% CI, -5.79 to -1.35). CONCLUSIONS: In this study population, nonfasting TG, HDL-C, and LDL-C levels successfully identified almost all patients who did not meet ATP III guidelines for cholesterol levels. No clinically significant difference was found in diabetic or nondiabetic patients.

Adult↗
PubMed2003

Effects of nabumetone, celecoxib, and ibuprofen on blood pressure control in hypertensive patients on angiotensin converting enzyme inhibitors.

Nonsteroidal anti-inflammatory drugs interfere with certain antihypertensive therapies. In a double-blind study, 385 hypertensive patients stabilized on an angiotensin converting enzyme inhibitor were treated with nabumetone, celecoxib, ibuprofen, or placebo for 4 weeks. Ibuprofen caused significantly greater increases in systolic (P < .001) and diastolic (P < .01) blood pressures (BPs) compared to placebo, but not nabumetone or celecoxib. The proportion of patients with systolic BP increases of clinical concern at end point was significantly higher (P < .001) for the ibuprofen group (16.7%; 15 of 90), but not for the nabumetone group (5.5%; 5 of 91) or the celecoxib group (4.6%; 4 of 87) compared to the placebo group (1.1%; 1 of 91).

Adult↗
PubMed2002

The directional atomic solvation energy: an atom-based potential for the assignment of protein sequences to known folds.

The Directional Atomic Solvation EnergY (DASEY) is an atom-based description of the environment of an amino acid position within a known 3D protein structure. The DASEY has been developed to align and score a probe amino acid sequence to a library of template protein structures for fold assignment. DASEY is computed by summing the atomic solvation parameters of atoms falling within a tetrahedral sector, or petal, extending 16 A along each of the four bond axes of each alpha-carbon atom of the protein. The DASEY discriminates between pairs of structurally equivalent positions and random pairs in protein structures sharing a fold but belonging to different superfamilies, unlike some previous descriptors of protein environments, such as buried area. Furthermore, the DASEY values have characteristic patterns of residue replacement, an essential feature of a successful fold assignment method. Benchmarking fold assignment with DASEY achieves coverage of 56% of sequences with 90% accuracy when probe sequences are matched to protein structural templates belonging to the same fold but to a different superfamily, an improvement of greater than 200% over a previous method.

Algorithms↗
PubMed2002

When the time comes to talk about HIV: factors associated with diagnostic disclosure and emotional distress in HIV-infected children.

OBJECTIVE: To determine factors related to the timing and probability of nondisclosure of HIV status to perinatally HIV-infected children, and to explore factors associated with emotional distress in HIV-infected children. METHODS: This is a cross-sectional study of 51 HIV-infected children based on medical records, parent interviews, and child assessments. RESULTS: 1) Probability of earlier age of disclosure is associated with higher child IQ (p =.04) and more family expressiveness (p =.01); 2) controlling for child age, disclosure status at time of study is associated with major life events, but not with medical status; and 3) factors associated with increased parent-rated anxiety in HIV-infected children in univariate analyses are: HIV disclosure (p =.04), other major life events (p =.001), higher medication dose frequency ( p=.01), and child age (p =.01). Increased depression is associated only with more medication doses (p =.02). CONCLUSION: These data indicate that higher child IQ and greater family expressiveness increase the probability of earlier diagnostic disclosure to HIV-infected children. Factors associated with emotional distress highlight important areas of clinical attention. These data suggest that diagnostic disclosure may not necessarily minimize emotional distress, indicating the need for further evaluation of the appropriate timing and type of disclosure for pediatric HIV.

Adolescent↗
PubMed2002

Advanced solid phase extraction using molecularly imprinted polymers for the determination of quercetin in red wine.

Solid phase extraction (SPE) based on molecularly imprinted polymers (MIPs) is a novel approach for sample preparation and preconcentration, gaining increased interest in the fields of environmental, clinical, and food analysis. The first application combining MIPs with SPE for advanced beverage analysis is reported. MIPs for the flavonoid quercetin have been generated, using quercetin as a template molecule in a self-assembly approach and yielding imprinting of 1% of the used template. The MIP achieved a capacity of 0.4 g quercetin per gram polymer and a recovery rate of 98.2%. The application of these synthetic receptors as SPE material for the selective extraction and preconcentration of quercetin from synthetic and red wine samples was investigated. Red wine samples from a French Merlot were directly applied onto the SPE cartridge. The collected fractions were analyzed by high-pressure liquid chromatography. For verification of the obtained results, a similarly prepared nonimprinted polymer and a classical octadecyl silane reversed-phase cartridge were applied as the SPE matrix during control experiments. The MIP enabled the selective extraction of quercetin from a complex matrix, such as red wine, spiked with 8.8 mg per liter quercetin, demonstrating the potential of molecularly imprinted solid phase extraction for rapid, selective, and cost-effective sample pretreatment.

Acetonitriles↗
PubMed2002

Changing patterns of initial drug therapy for the treatment of hypertension in a Medicaid population, 1997-2000.

BACKGROUND: The US Joint National Committee (JNC) on prevention, detection, evaluation, and treatment of high blood pressure recommended beta-blockers and thiazide diuretics as the drugs of first choice for the initial treatment of hypertension. OBJECTIVE: This study was undertaken to determine whether the JNC guidelines were used by Maine physicians when initiating monotherapy for patients with newly diagnosed hypertension. METHODS: The Maine Medicaid database for 1997 through 2000 was searched using diagnostic codes and prescription data for the classes of drugs used to initiate monotherapy in patients with newly diagnosed hypertension who were followed up for at least 6 months. RESULTS: A total of 6246 patients were included in the study. In 1997 (n = 1339), there was a fairly equal distribution between the use of beta-blockers (22.6%), diuretics (23.9%), angiotensin-converting enzyme (ACE) inhibitors (22.9%), and calcium channel blockers (18.3%). In 2000 (n = 964), beta-blockers (27.2%), diuretics (25.0%), and ACE inhibitors (26.5%) were used more often than calcium channel blockers (10.9%), but the differences were not statistically significant. There was no difference between men and women in any treatment group, and only diuretic use increased with age, but even this difference was not significant. In 1997, ACE inhibitors (30.1%) were prescribed more frequently than beta-blockers (24.7%), diuretics (7.8%), or calcium channel blockers (24.1%) to patients with newly diagnosed hypertension and congestive heart failure (n = 166), although the differences were not significant. In 2000, this group of patients (n = 297) received more diuretics (56.6%) than beta-blockers (16.2%) or ACE inhibitors (21.5%); calcium channel blockers were no longer used. The differences were not significant. In 1997, ACE inhibitors (51.2%) were prescribed more frequently than beta-blockers (10.0%), diuretics (32.1%), or calcium channel blockers (4.0%) to patients with newly diagnosed hypertension and diabetes (n = 299). In 2000, this group of patients (n = 295) again received more ACE inhibitors (66.1%) than beta-blockers (13.9%) or diuretics (14.9%); calcium channel blockers were no longer used. Again, these differences did not reach statistical significance. CONCLUSIONS: Although the use of calcium channel blockers as initial monotherapy for hypertension appears to have declined among Medicaid recipients in Maine since 1997, ACE inhibitors are still frequently prescribed for this purpose, especially among patients who have hypertension and congestive heart failure. These changes in drug utilization appear to reflect influence by the published JNC guidelines. However, there was still a large range of initial therapy across all drug classes not justified by published guidelines or outcome studies.

Adrenergic beta-Antagonists↗
PubMed2002

The utilization of a new yellow light laser (578 nm) for the treatment of class I red telangiectasia of the lower extremities.

BACKGROUND: A dual-wavelength approach is necessary in order to achieve consistent results when utilizing lasers and intense pulsed light sources to treat red and blue lower extremity vessels. In this regard, short-wavelength technologies (500-800 nm) may be employed to treat red telangiectasia of less than 2 mm on the lower extremities. OBJECTIVE: To demonstrate a new yellow light laser utilizing a copper bromide medium and its potential efficacy in the treatment of red lower extremity telangiectasia of less than 2 mm. METHODS: Forty-six women (mean age 37 years) were treated in two private practice settings with a 578 nm yellow light laser with a circulating cooling window (1-4 degrees C). Class I red telangiectases of the thighs 1.5 mm or less in diameter were considered for treatment. Patients were treated with up to three treatments at 6-week intervals on a 5 cm2 surgical area of vessels utilizing a fluence of 50-55 J/cm2. Results were analyzed by macrophotographic imaging, double-blinded observer evaluation/optical chromatography, and a patient evaluation scale. RESULTS: An average of 1.7 patient treatment sessions produced significant clearing of 75-100% in 71.8% of patients. The mean erythema index showed significant lightening (51-65a+) in the study population. Finally, 76.1% of patients reported great satisfaction with the results of their treatment session. CONCLUSION: A new 578 nm copper bromide (CuBr) yellow light laser produces excellent results in eradicating red telangiectases of the lower extremities that are less than 2 mm in diameter.

Adult↗
PubMed2002

Intense pulsed-light photorejuvenation.

Intense pulsed light photorejuvenation represents a novel mode of treatment of photodamaged skin. A broad-spectrum flashlamp (500-1200 nm) targets chromophores reversing pigmentation, vascular and pilosebaceous aberrations. Both cytokine mediated as well as thermally induced deep dermal remodeling may be achieved using the varied polychromatic wavelengths associated with this technology. Inflammatory dermatosis such as rosacea may also be addressed as well. A structural approach to non-ablative rejuvenation utilizing intense pulsed light is associated with high patient satisfaction and minimal adverse sequelae.

Facial Dermatoses↗
PubMed2002

Primary renal lymphoma and hypercalcemia in a child.

Renal lymphoma is most frequently due to secondary lymphomatous infiltration of the kidneys in advanced stage disease. Rarely, are the kidneys the tissue of origin. We describe a 15-year-old male presenting with hypercalcemia and acute renal failure, due to a bilateral "primary B-cell lymphoma of the kidneys". The diagnosis was established by percutaneous needle biopsy of the right kidney. His disease was metastatic to multiple bones. His presenting features radiological findings and biopsy results are unique. We report his case, and review the pediatric literature.

Adolescent↗
PubMed2002

Profiling patterned transcripts in Drosophila embryos.

Here we describe a high-throughput screen to isolate transcripts with spatially restricted patterns of expression in early embryos. Our approach utilizes robotic automation for rapid analysis of sequence-selected cDNAs in a whole-mount in situ hybridization assay. We determined the spatial distribution of a random collection of 778 different genes from an embryonic cDNA library and show that a significant fraction of these exhibit patterned profiles of expression. In addition, gene ontology studies revealed groups of gene products exhibiting shared expression patterns, providing new insights into the largely overlooked effector molecules that function in development. As described in this paper, automated hybridization to whole-mount embryos in situ proved to be straightforward and provided us with a very powerful method for the global survey of gene expression in early embryos. From the perspective of biological significance, our finding that many spatially restricted transcripts correspond to loci encoding novel transcripts that have not been previously identified in nearly saturating genetic screens for maternal effect and zygotic lethals is particularly notable.

Animals↗
PubMed1994

Clinical Efficacy and Safety of Lower-Dose Indapamide Therapy in the Treatment of Patients with Mild to Moderate Hypertension.

Previous clinical studies with indapamide, an indoline antihypertensive drug with diuretic and vasodilating activities, have shown a dose relationship associated with potassium loss. Two placebo-controlled, randomized, double-blind, parallel clinical studies were, therefore, done to evaluate the safety and efficacy of a low dose (1.25 mg) of indapamide and to determine if an improved safety profile could be produced while maintaining efficacy with a 1.25-mg dose in patients with mild to moderate essential hypertension. Four hundred seventeen (417) adult patients with mild to moderate essential hypertension (sitting diastolic blood pressure greater-than-or-equal 95 mmHg and less-than-or-equal 110 mmHg) were enrolled in two clinical studies; 209 patients were randomized to indapamide 1.25 mg and 208 patients to placebo. Patients received single-blind placebo for a 4-week washout period followed by an 8-week double-blind treatment period during which patients received either indapamide 1.25 mg or placebo. The primary efficacy endpoint was the mean change from baseline to week 8 in sitting diastolic blood pressure. Secondary efficacy variables were the proportion of patients whose sitting diastolic blood pressure had decreased greater-than-or-equal 10 mmHg and/or had a sitting diastolic blood pressure of less-than-or-equal 90 mmHg (treatment success) at all visits and at endpoint, mean changes from baseline in sitting diastolic blood pressure at designated timepoints and at endpoint, and mean changes from baseline in standing diastolic blood pressure and in sitting and standing systolic blood pressure at all visits and at endpoint. Results of these trials were pooled in order to have a larger patient population in an attempt to detect trends not readily apparent with a smaller sample size. In the primary analysis, indapamide produced statistically significantly (p = 0.0001) greater reductions in sitting diastolic blood pressure than placebo after 8 weeks of therapy. In the secondary analysis, the percentage of indapamide-treated patients who achieved treatment success after 8 weeks of therapy was statistically significantly (p < 0.0001) higher compared to placebo-treated patients. In addition, indapamide produced a statistically significantly (p = 0.0001) superior reduction compared to placebo in sitting systolic and standing systolic and diastolic blood pressure after 8 weeks of therapy. The incidence of drug-related adverse events between patients in the indapamide and placebo groups was similar. There were no clinically meaningful differences in laboratory values, including serum potassium, between the patients in the indapamide and placebo groups. Low-dose (1.25 mg) indapamide proved to be safe and effective in the treatment of mild to moderate hypertension.

Journal Article↗