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Biomedical subjects

J Friedman

Publications and source records attributed to J Friedman.

At least 181 records · Page 10Linked to original sources
PubMed1986

Noninvasive quantification of the extent of jeopardized myocardium in patients with single-vessel coronary disease by stress thallium-201 single-photon emission computerized rotational tomography.

In 22 patients with single-vessel coronary artery disease and no history of infarction, stress Tl-201 rotational tomography was used to quantify the extent of jeopardized myocardium. The vertical long- and short-axis tomograms were quantified by means of maximum-count circumferential profile analysis. The scintigraphic extent of jeopardized myocardium was expressed as the percentage of profile points falling 2.5 standard deviations below a previously established mean normal profile and was correlated to a quantitatively expressed angiographic extent of jeopardized myocardium. The extent of jeopardized myocardium varied from 1% to 55% by tomography and 8% to 50% by angiography and correlated with an r = 0.79 and a 10% standard error of the estimate. Defect intensity, reflecting the mean depth by which the abnormal points fell below the normal value of greater than or equal to 10%, was 100% specific for a coronary stenosis of greater than or equal to 70%. In conclusion, this study demonstrates that: patients with single-vessel disease have highly variable extents of hypoperfused myocardium defined by Tl-201 tomography and coronary arteriography, there is a fair relationship between angiographic jeopardy score and perfusion defects by Tl-201 tomography during exercise, and Tl-201 tomography may be used to noninvasively determine the extent of hypoperfused myocardium in coronary artery disease.

Aged↗
PubMed1986

A preliminary classification of the healing potential of medicinal plants, based on a rational analysis of an ethnopharmacological field survey among Bedouins in the Negev desert, Israel.

In the course of an ethnopharmacological survey carried out among the Bedouins of the Negev desert, it was noticed that in addition to the use of modern medical services, medicinal plants were also being employed. We deemed it worthwhile, therefore, to investigate the current status of herbal medicine among the Negev Bedouins and to evaluate the relative efficiency of the plants used. To evaluate plant effectiveness by enquiries among patients once treated was found to be difficult and impractical. Hence, each interviewed informant was first requested to volunteer information on the plants and their uses. Next, to avoid the risk of memory failure, a list of 50 commonly used species was read out and the informant was asked to provide information on any that were familiar to him as medicinal herbs. Of 81 plant species mentioned by our 27 informants, 41 were named or recognized by more than 3. These species were arranged in accordance with the percentage of informants suggesting the same medicinal use for a given species as compared with the total number of informants reporting any sort of use for that plant. The obtained ratio was defined as the fidelity level (FL). The rank-order priority (ROP) of the plants was derived from these FL values. The relative popularity level (RPL) of the plants encountered was determined and plants were accordingly designated as "popular" or "unpopular". FL values were further adjusted, according to RPL value. We found that the bark of Phagnalon rupestre is widely used to induce deliberate burns for the healing of various ailments (ROP = 100), while infusion of the shoots of Teucrium polium, or of Artemisia herba-alba is employed to a lesser degree (ROP = 66 and 56, respectively) to relieve stomach disorders. Because the latter two species show fairly high ROP and are seen to be directly curative, they merit further investigation. Additional findings and implications of our ethnopharmacological survey are duly discussed.

Humans↗
PubMed1986

Expression of a cholecystokinin precursor-related peptide in vertebrate and invertebrate tissues.

We have developed a radioimmunoassay for the nonapeptide predicted by cDNA sequence analysis to reside at the extreme C-terminus of the mouse cholecystokinin (CCK) precursor. Sensitivity of the assay is 1 pg synthetic CCK precursor-related peptide (CCK-PRP)/ml. The antibody has no cross-reactivity with cholecystokinin, gastrin, or a variety of other known neuropeptides. We have employed this assay to demonstrate the presence, in rodent brain, gut, and peripheral plasma, of peptides with immunological properties that are identical to, and gel filtration characteristics that are very similar to, those of the synthetic CCK-PRP. We have also detected a similar peptide in the culture media of a human CCK-producing tumor. The molar ratios of immunoreactive CCK-PRP/CCK vary widely among tissues of origin and during ontogeny, suggesting regional and developmental differences in the turnover rates or in posttranslational modification of the two peptides. Our studies suggest that peptides very similar to intact CCK-PRP are posttranslationally liberated from the cholecystokinin precursor in a variety of tissues and may have neurotransmitter and/or hormonal functions distinct from those of CCK. Relatively high quantities of material immunologically indistinguishable from CCK-PRP were also found in several coelenterate species, indicating that this epitope arose as early in evolution as did CCK.

Aging↗
PubMed1986

The onset of drinking and intoxication among university students.

To study the effect of the onset of drinking on subsequent alcohol use, self-administered questionnaires were completed by 856 unmarried undergraduate students from two universities in the southeastern region of the United States. The present study focuses on the 524 (61.2%) students who reported using alcohol at least occasionally. In this subsample, the strongest predictors of the extent of undergraduate intoxication are the frequency of intoxication at the onset of drinking and age at the onset. The more often an individual drinks to intoxication and the younger that individual begins to drink, the more frequently he or she will become intoxicated when a university student. Racial differences in the extent of undergraduate intoxication were also found. White students were markedly more prone to intoxication than were Black students. Sex differences, although not statistically significant, showed a tendency for drunkenness among male undergraduates to exceed that among female undergraduates. The implications of the findings for intervention and prevention strategies are discussed.

Adult↗
PubMed1985

Clinical follow-up of couples treated for sexual dysfunction.

The present status of 38 couples who had been treated at a clinic for sexual dysfunction 3 years previously was determined by a self-report assessment battery. The battery consisted of the Sexual Interaction Inventory, the Locke-Wallace Marriage Inventory, and the Sexual History Form completed at pretreatment, immediately posttreatment, 3 months after treatment, and at 3-year follow-up. An additional Follow-up Questionnaire was completed at the 3-year point only. At 3-year follow-up, analysis of data by diagnostic category indicated that sexual desire dysfunction for both men and women was particularly resistant to sustained behavioral change. Men with erectile difficulty reported significant improvement in their ability to maintain erections during intercourse but not in their ability to achieve erections prior to intercourse. Data from men with premature ejaculation revealed some immediate significant posttherapy gains, which, with the exception of length of foreplay, were not sustained at 3-year follow-up. For women with global inorgasmia, a significant increase in orgasmic response was reported. Data from women with situational orgasmic difficulties indicated some success in improving frequency of orgasm through masturbation and through genital caress; however, these changes did not reach statistical significance. Across all diagnostic categories, both men and women respondents reported increased satisfaction in their sexual relationship. Satisfaction in the marital relationship showed a more varied response pattern.

Adult↗
PubMed1985

Thallium-201 stress-redistribution myocardial rotational tomography: development of criteria for visual interpretation.

Despite high sensitivity and specificity for overall detection of coronary artery disease (CAD), planar stress-redistribution thallium-201 (Tl-201) scintigraphy remains suboptimal in localizing disease, because of overlap of myocardial segments. Single photon emission computerized tomography (SPECT), by providing three-dimensional representation of myocardial Tl-201, offers promise for improved localization of CAD. In 50 consecutive patients (22 normal and 28 with CAD), who underwent SPECT stress-redistribution Tl-201 imaging, we systemically developed visual interpretive criteria for perfusion abnormality on SPECT. For overall detection of disease, the best criterion for abnormality was greater than or equal to 8 sectors of moderately decreased Tl-201 uptake. With this criterion, the true positive and true negative rates for overall detection of disease were 96% and 91%, respectively. The best criterion for significant defect in the anterior or posterior coronary circulation was greater than or equal to 3 sectors of moderately decreased Tl-201 uptake. With this criterion, the true positive and true negative rates for anterior circulation disease were 71% and 100%, respectively. With respect to posterior circulation disease, the true positive and true negative rates were 100% and 50%, respectively. Regarding identification of dual circulation disease, the true positive and true negative rates were 71% and 82%, respectively.

Adult↗
PubMed1985

Differential expression of the mouse cholecystokinin gene during brain and gut development.

Cholecystokinin (CCK) is a neuropeptide found in brain and intestine. In this report, we have isolated a cDNA clone that encodes CCK from a mouse brain cDNA library. This cDNA clone has extensive homology to CCK precursors that have been sequenced previously. Southern blots of genomic DNA probed with this cDNA clone revealed single bands for each of eight different restriction enzymes, all of which could be accounted for by a single genomic clone, suggesting that the CCK gene is present as a single-copy gene in mice. RNA blots, primer extensions, and S1 nuclease protection assays have suggested that the same RNA start site is utilized in brain and in gut. Finally, we have shown, by using RNA blots and a radioimmunoassay specific for CCK, that CCK is expressed at maximum adult levels in intestine at birth but that adult concentrations of CCK and its mRNA are not reached in brain until much later in development.

Animals↗
PubMed1985

Validity and reliability of a rating scale for the primary torsion dystonias.

For quantitative assessment of the primary torsion dystonias, a rating scale is proposed that has two sections--a Movement Scale, based on examination, and a Disability Scale, based on the patient's statements about seven activities of daily living. We assessed the validity of the Movement Scale by comparing scores with a ranking of patients according to dystonia severity and with ratings of the patients on the Disability Scale. In addition, we assessed the inter-and intra-rater reliability of the scale by comparing independent scorings of patients by four examiners and by comparing scorings by the same examiners performed at different times. We found that the Movement Scale was a valid and reliable indicator of the severity of primary torsion dystonia.

Activities of Daily Living↗
PubMed1985

Epinephrine-induced sequestration of the beta-adrenergic receptor in cultured S49 WT and cyc- lymphoma cells.

Pretreatment of either intact wild type S49 lymphoma cells (WT) or the uncoupled variants, cyc-, H21a, or UNC with epinephrine results in the redistribution of 20-30% of the beta-adrenergic receptors into a light vesicle fraction in sucrose gradients. Since the variants are uncoupled with respect to hormonal stimulation of adenylate cyclase, it appears that productive interaction with Gs is not required for the sequestration of beta-adrenergic receptors. Characterization of the epinephrine-induced redistribution of the beta-adrenergic receptor has revealed the following: The EC50 for the redistribution in WT cells was between 100 and 200 nM. Pretreatment of WT cells with 50 nM epinephrine for 30 min induced only a slight redistribution of receptors in sucrose gradients but produced a significant desensitization of adenylate cyclase. The desensitization was characterized by an increase in the Kact of epinephrine stimulation of adenylate cyclase while the Vmax was unaltered. Pretreatment with 10 microM epinephrine resulted in a significant decrease in the Vmax (50%) of epinephrine stimulation of adenylate cyclase and a 3-fold increase in Kact in the heavy vesicles. The beta-receptors in the light vesicle fraction of WT were uncoupled from adenylate cyclase and displayed low affinity for epinephrine binding, comparable to the cyc-. The "desensitized" receptor in the light vesicle fractions of cyc- was capable of stimulating adenylate following reconstitution with cholate extracts of WT membranes containing Gs. The molecular weight of the photolabeled beta-receptor in the light vesicle fractions (65,000 +/- 2,000) was not significantly different from the Mr 65,000 polypeptide photolabeled in the heavy fractions. The Mr 55,000 beta-receptor polypeptide was not detected in the light vesicles. Our results suggest first that the redistribution of the beta-receptor into light vesicles may follow an earlier stage of desensitization, and second that the beta-receptor in light vesicles while sequestered from Gs is capable of activating adenylate cyclase.

Adenylyl Cyclase Inhibitors↗
PubMed1985

Quantification of rotational thallium-201 myocardial tomography.

A comprehensive method is described for quantification of the relative 3-dimensional distribution of Tl-201 in the myocardium, following stress and subsequent washout. The method uses maximal-count circumferential profiles of well-defined long- and short-axis tomograms to determine the 3-dimensional distribution of Tl-201; it then maps this distribution onto a 2-dimensional polar representation. Abnormal thallium distribution or washout is identified by automatic computer comparison of each patient's profile with the corresponding lower limits of normal profiles. Abnormality is expressed as a percentage of the entire myocardium by use of polar maps for extent and severity. The binary extent map expresses the degree of abnormality. Preliminary criteria for abnormality were derived from the tomographic results of 25 normals and 28 patients with documented coronary artery disease. The results were normal in 23 of the 25 normals and were abnormal in 25 of the 28 CAD patients. In addition, the computer output correctly localized the presence or absence of disease in 46 of 56 coronary circulations.

Adult↗
PubMed1984

Characterization of a halobacterial gene affecting bacterio-opsin gene expression.

A substantial number of spontaneous bacterio-opsin mutants of Halobacterium halobium are the result of insertion elements up to 1400 bp upstream of the bacterio-opsin (bop) gene. The nucleotide sequence of 1800 bp upstream of the bop gene has been determined. There is a 1118 bp open reading frame (ORF) located within this region which is transcribed and which coincides with the distribution of insertion elements upstream of the bop gene in Bop mutants. Therefore, we propose that there is a gene (brp gene) 526 bp upstream of the bop gene. This putative gene is transcribed in the opposite direction as the bop gene and could encode a protein of 37,500 D (359 amino acids) with a codon usage similar to bacterio-opsin. The 5' terminus of the brp transcript has been determined. The brp transcript and the bop mRNA are complementary for 13 residues near their 5' termini and both transcripts start at or near the initiating codon of the gene. Both transcripts could form similar hairpin loop structures at their 5' termini which contain possible ribosomal binding sites. The DNA sequences immediately upstream of the bop and the brp genes have significant homologies and there is a short complementary sequence. The role of the brp gene in bacterio-opsin gene expression is unclear.

Amino Acid Sequence↗
PubMed1984

Characterization of insertions affecting the expression of the bacterio-opsin gene in Halobacterium halobium.

We have determined the sequence of the inverted repeats and duplicated target DNA of the halobacterial insertion elements ISH2 (520 bp), ISH23 (900 bp) and ISH24 (3000 bp) associated with bacterio-opsin (bop) mutants. ISH2 has a perfect 19 bp inverted repeat (3,5), while both ISH23 and ISH24 have imperfect inverted repeats of 29 bp and 14 bp respectively. ISH23 was shown to be highly homologous to ISH50 (6). Variable lengths of duplicated target DNA are found when ISH2 and ISH23 (ISH50) transpose into different sites. A 550 bp DNA insert ("ISH25") reverts the Bop mutation caused by ISH24. "ISH25" lacks typical structural features of a transposable element. "ISH25" and ISH24 are found adjacent to each other upstream of the bop gene. An identical arrangement of "ISH25" and ISH24 is found in the cccDNA of H. halobium NRC817. Comparative sequence analysis of both areas suggests that the translocation of "ISH25" to the bop gene region occurred by a recombination event.

Bacteriorhodopsins↗