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Biomedical subjects

B Goldberg

Publications and source records attributed to B Goldberg.

At least 235 records · Page 13Linked to original sources
PubMedDate not supplied

Regulatory idiotopes, parallel sets and internal image of the antigen within the polyfructosan-A48 idiotypic network.

The study of the A48 idiotype anti-beta 2----6-polyfructosan immune response was used as a tool to investigate the various postulates of the immune network theory. The results of this study have shown: that only certain idiotopes, designated as regulatory idiotopes, play a role in idiotype-regulated immune responses; that some of the A48 idiotopes were expressed on a myeloma protein with unknown binding activity (MOPC173) and on MOPC167, a phosphorylcholine-binding myeloma protein; that one out of six monoclonal antiidiotypic antibodies tested carried the internal image of the antigen and could elicit an antibacterial levan immune response in mice treated at birth with bacterial levan or polyclonal anti-A48Id antibodies.

Animals↗
PubMedDate not supplied

Decrease in viral load associated with topical dinitrochlorobenzene therapy in HIV disease.

Quantitative measurement of human immunodeficiency virus (HIV) RNA is being used to assess the efficacy of various treatment modalities in HIV disease. Topical dinitrochlorobenzene (DNCB) therapy has been associated with improved clinical and immunologic parameters in HIV-infected patients. We have now examined the effect of topical DNCB treatment on plasma HIV RNA levels in a small prospective study. Eight HIV-infected subjects had T-cell counts and plasma viral load measured prior to initiation of DNCB therapy and 3-4 months after starting treatment. Six patients who refused DNCB therapy served as simultaneous controls. The mean CD4 and CD8 T-cell counts did not change significantly in either group over the study period. In contrast, plasma HIV RNA levels decreased one-half to greater than one log in each DNCB-treated subject, and the decrease in viral copies was statistically significant (p = 0.006). In the control group, plasma HIV RNA levels increased significantly over the course of the study (p = 0.037). We conclude that topical DNCB therapy has the ability to lower viral load in HIV-infected patients. The long-term effect on viral burden of this inexpensive, readily available therapeutic modality merits further investigation.

Administration, Topical↗
PubMedDate not supplied

Weight gain associated with protease inhibitor therapy in HIV-infected patients.

Weight loss and wasting are significant complications of HIV disease. HIV protease inhibitor therapy promotes clinical, immunologic and virologic improvement in HIV-infected patients. In this study, we sought to determine the specific effect of HIV protease inhibitors on patient weight. Ten consecutive HIV patients were treated with protease inhibitor-containing regimens over six months. CD4 T-cell counts, plasma viral load levels and bariatric changes were monitored during the study. Patients experienced a mean weight gain of 19 Pounds (P = 0.006). There was a significant increase in mean CD4 T-cell count (P = 0.008) and a significant decrease in mean viral load level (P = 0.004). The increase in CD4 T cells did not correlate with weight gain, whereas the decrease in viral load did show a significant correlation with the weight increase (P = 0.003). The mechanism of protease inhibitor-induced weight gain is discussed. The medications may also be useful for wasting diseases unrelated to HIV.

Anti-HIV Agents↗
PubMedDate not supplied

A descriptive study of medical and chiropractic patients with chronic low back pain and sciatica: management by physicians (practice activities) and patients (self-management).

BACKGROUND: A practice-based study of ambulatory patients with low back pain noted a long-term outcome advantage for self-referred chiropractic (DC) patients over medical (MD) patients within a subgroup of patients with chronic low back pain and radiating pain below the knee. The frequency of self-care education by physicians in both provider cohorts coupled with current thinking on management of chronic low back pain led to an exploration and description of physicians' noncore practice activities and patients' self-management attitudes and behaviors. METHODS: A longitudinal, practice-based, observational study was undertaken in 14 general practice and 51 chiropractic community-based clinics. We enrolled 2945 consecutive patients with ambulatory low back pain of mechanical origin; of these, 268 comprised the subgroup of patients with chronic low back pain and radiating pain below the knee. The patients' low back status was followed for 1 year. Data on physicians' practice activities were obtained from doctor questionnaires completed at each patient visit and from chart abstraction. Patient data obtained from self-administered questionnaires at enrollment included sociodemographics, complaint characteristics, health status, and health encounter preferences. Questionnaires mailed at 2 weeks, 1 month, 3 months, 6 months, and 12 months collected data on low back complaint status and satisfaction with treatment. At 1 to 3 years follow-up, mailed questionnaires collected data on patients' self-management attitudes and behaviors. RESULTS: Physicians' core practice activities were as expected. Exercise plans and self-care education (>55%) were conspicuous in the frequency of their use in the DC cohort. MD patients appeared to rely more on family and friends for support during periods of back trouble. DC patients were characterized by greater self-efficacy motivation (P = .000). Both groups showed evidence of self-care activities during and between bouts of back pain, although MD patients were far more likely to choose bed rest (P = .007). CONCLUSIONS: The chiropractic encounter may have enhanced patients' self-efficacy motivation, leading to better coping abilities and better pain and disability outcomes. Understanding, respecting, and capitalizing on the role and influence of psychosocial factors can help all physicians become more effective healers and counselors for their patients with back pain.

Adult↗
PubMedDate not supplied

Diagnostic value of serum procollagen peptide measurements in alcoholic liver disease.

Procollagen type I carboxyterminal and type III aminoterminal peptide concentrations were measured in sera of 60 patients with alcoholic and 14 with nonalcoholic liver disease to study whether these assays are useful as clinical tests to differentiate various stages of alcoholic liver injury. Both propeptides were markedly elevated in alcoholic hepatitis and cirrhosis: procollagen type III peptide in 90% and type I peptide in 60-80% of these patients. Moderately increased values were found less frequently in patients with fatty liver. These tests did not differentiate patients with simple fatty liver from those with fatty liver and early fibrosis. There was a significant difference in serum procollagen type III peptide between fatty liver and both alcoholic hepatitis and cirrhosis (p less than 0.001), and in type I peptide between fatty liver and alcoholic hepatitis (p less than 0.005). Although serum peptide values correlated with the degree of liver fibrosis, appreciable overlap of values was found between the various groups. The peptide concentrations also seemed to be related to the degree of hepatic inflammation, and the highest values were observed in a subgroup of patients with alcoholic hepatitis in whom numerous Mallory bodies were found. The data suggest that in alcoholic liver diseases, serum collagen propeptide determination may be useful in diagnosing severe alcoholic hepatitis.

Adult↗
PubMedDate not supplied

Subcellular localization of the enzymes of the arginine dihydrolase pathway in Trichomonas vaginalis and Tritrichomonas foetus.

The enzymes of the arginine dihydrolase pathway were demonstrated in Tritrichomonas foetus and their subcellular localization determined for both T. foetus and Trichomonas vaginalis. Ornithine carbamyltransferase (anabolic and catabolic activities), ornithine decarboxylase and carbamate kinase activity were localized predominately (56-80%) in the non sedimentable fraction of both species. A large proportion (35-40%) of the arginine deiminase was, however, recovered in the large granular fraction, and this distribution was unchanged by increasing the ionic strength of the buffer. Upon density gradient centrifugation the particles containing arginine deiminase activity had an isopycnic density of 1.09 g/ml in percoll, and separated from hydrogenosomes (1.18 g/ml) and lysosomes (1.12 g/ml). Arginine deiminase was also the only enzyme of the dihydrolase pathway which demonstrated latency upon treatment of the 1.09 g/ml fraction with non-ionic detergents. The results demonstrate the presence of the arginine dihydrolase pathway in T. foetus and indicate that at least a portion of the arginine deiminase in trichomonads is membrane associated.

Animals↗
PubMedDate not supplied

Rapid methylation of cell proteins and lipids in Trypanosoma brucei.

The fate of the [methyl-14C] group of S-adenosylmethionine (AdoMet) in bloodstream forms of Trypanosoma brucei brucei, was studied. Trypanosomes were incubated with either [methyl-14C]methionine, [U-14C]methionine, S-[methyl-14C]AdoMet or [33S]methionine and incorporation into the total TCA precipitable fractions was followed. Incorporation of label into protein through methylation was estimated by comparing molar incorporation of [methyl-14C] and [U-14C]methionine to [35S]methionine. After 4-h incubation with [U-14C]methionine, [methyl-14C]methionine or [35S]methionine, cells incorporated label at mean rates of 2,880 pmol, 1,305 pmol and 296 pmol per mg total cellular protein, respectively. Cells incubated with [U-14C] or [methyl-14C]methionine in the presence of cycloheximide (50 micrograms/ml) for four hours incorporated label eight- and twofold more rapidly, respectively, than cells incubated with [35S]methionine and cycloheximide. [Methyl-14C] and [U-14C]methionine incorporation were > 85% decreased by co-incubation with unlabeled AdoMet (1 mM). The level of protein methylation remaining after 4-h treatment with cycloheximide was also inhibited with unlabeled AdoMet. The acid precipitable label from [U-14C]methionine incorporation was not appreciably hydrolyzed by DNAse or RNAse treatment but was 95% solubilized by proteinase K. [U-14C]methionine incorporated into the TCA precipitable fraction was susceptible to alkaline borate treatment, indicating that much of this label (55%) was incorporated as carboxymethyl groups. The rate of total lipid methylation was found to be 1.5 times that of protein methylation by incubating cells with [U-14C]methionine for six hours and differential extraction of the TCA lysate. These studies show T. b. brucei maintains rapid lipid and protein methylation, confirming previous studies demonstrating rapid conversion of methionine to AdoMet and subsequent production of post-methylation products of AdoMet in African trypanosomes.

Animals↗
PubMedDate not supplied

Effects of carboxylmethylation and polyamine synthesis inhibitors on methylation of Trypanosoma brucei cellular proteins and lipids.

The fate of methionine in eukaryotic cells is divided between protein synthesis and the branched pathway encompassing polyamine synthesis, methylation of proteins and lipids, and transsulphuration reactions. Aside from protein synthesis, the first step to all other uses of methionine is conversion to S-adenosylmethionine. Blockade of polyamine synthesis in African trypanosomes by the ornithine decarboxylase inhibitor DL-alpha-difluoromethylornithine (Ornidyl, DFMO) the AdoMet decarboxylase inhibitor 5'-[[(Z)-4-amino-2-butenyl]-methylamino]-5'-deoxyadenosine or the protein methylase inhibitor sinefungin induces dramatic increases in intracellular AdoMet. In a previous study, distribution and pool sizes of [35S] or [U-14C]methionine were followed in bloodform trypanosomes as incorporation into the total TCA precipitable fractions. In the present study, the effects of pretreatment with DFMO (1 mM), MDL 73811 (1 microM) and sinefugin (2 nM) on [35S] and [U-14C]methionine incorporation were studied in blood forms. DFMO or MDL 73811 pretreatment increased protein methylation 1.5-fold through incorporation of [U14C]methionine, while sinefungin caused a 40% reduction of incorporation. The increases in incorporation of [U-14C]methionine due to DFMO and MDL 73811 were reduced 40% to 70% by including cold AdoMet (1 mM) in the incubation medium, an indication of AdoMet transport by bloodform trypanosomes and the utilization of [U-14C]methionine as AdoMet. Exogenous AdoMet had no effect on [35S]methionine incorporation. The agents studied are curative for African trypanosomiasis infections, either clinically (DFMO) or in model infections (MDL 73811, sinefungin) and thus highlight interference with AdoMet metabolism and methylation reactions as biochemical consequences of these agents.

Adenosine↗