Search PubMed⌕ Search

Biomedical subjects

R Stern

Publications and source records attributed to R Stern.

At least 235 records · Page 13Linked to original sources
PubMed1979

Paradoxes in programming for chronic patients in a community clinic.

In attempting to build a successful program for chronic patients at the Somerville (Mass.) Mental Health Clinic, the authors first found it necessary to uncover, address, and resolve six fundamental paradoxes engendered by deinstitutionalization that were stressful to mental health clinic staff and inhibited effective programming. The paradoxes involve issues relating to community mental health ideology, clinicians' sources of self-esteem and professional ability, and clinicians' views of chronicity and the deinstitutionalization movement in general. Resolution of the paradoxes requires major value changes, which can be brought about by effective clinical leaders who serve as role models and teachers, and who set the tone for patient care.

Attitude of Health Personnel↗
PubMed1979

Hand-mirror cell leukemia associated with mental retardation: immunologic, chromosome, and morphological studies.

Cycochemical, morphological, immunologic, and cytogenetic studies were carried out on hand-mirror cells (HMC) from a mentally retarded patient with a constitutional chromosome abnormality, 46,XX,r(21), and acute lymphoblastic leukemia. Scanning electron and differential interference contrast microscopy showed microspikes on the uropodia, but little evidence of cellular motility, despite formation and disappearance of individual uropodia in cell suspensions. The cells rosetted with sheep erythrocytes, suggesting T-cell origin. Cells derived from the bone marrow (80% HMC) showed a high degree of polyploidy (60%) and a bimodal chromosome number of 49 (49,XX,+10,-21, +3 rings) and 94 (6 no. 10, 3 no. 18, 2 no. 21 chromosomes, 3 ring chromosomes, plus 4 copies of each other chromosome).

Bone Marrow↗
PubMed1978

The effect of L-dopa and propranolol on human CSF cyclic nucleotides.

Human CSF cyclic AMP and cyclic GMP have been measured as possible indicators of activity of central neurotransmitter-sensitive adenylate or guanylate cyclase. In an attempt to help to identify the specific neurotransmitter systems of origin of human CSF cyclic AMP and GMP, we studied Parkinson patients with and without L-dopa therapy and schizophrenic patients before and after propranolol therapy. No effect of L-dopa or propranolol was found on CSF cyclic nucleotides. However, Parkinson patients had a 40-50% reduction of CSF cyclic AMP and a 80-90% reduction of CSF cyclic GMP compared with the schizophrenic patients. Implications of this finding are discussed.

Adult↗
PubMed1978

The synthesis of presumptive procollagen messenger ribonucleic acid in the calvaria of the developing chick embryo.

The presumptive messenger RNAs for type I procollagen were isolated from chick embryo calvaria at various stages of development. Poly(A)-containing RNA fractions from denaturing sucrose gradients directed protein synthesis in a cell-free system derived from wheat germ. Procollagen mRNA activity was detected in a region of about 26 S. Approx. 80% of the labeled proline incorporated into cell-free product was susceptible to digestion by purified bacterial collagenase. The synthesis of procollagen mRNAs was followed during development. Comparison of the in vitro labeled mRNAs from calvaria of day 12--16 embryos indicated that the 26 S component was most pronounced at day 13 and decreased progressively towards day 16. In addition, incubation of calvaria with tritiated nucleosides for 1.5--25 h revealed that 26 S mRNA was significantly labeled only after prolonged periods. The results suggest that procollagen mRNA is a relatively stable species with a prolonged half-life compared to the majority of mRNAs in this tissue.

Animals↗
PubMed1978

Effect of ultrasonic irradiation on mammalian cells and chromosomes in vitro.

Human peripheral blood and HeLa cells were irradiated in vitro at the ultrasonic frequency of 65 kHz. The whole blood and HeLa cell suspensions were exposed to continuous and pulsed ultrasonic power levels of 0.12, 0.16, 0.72, 1.12 and 2.24 W for a period of one minute. The method of ultrasonic irradiation was carried out with the whole blood or HeLa cell suspensions coupled directly to a cylindrical transducer while heating of the cell suspensions in excess of 41 degrees c was avoided. Irradiated and unirradiated peripheral blood lymphocyte chromosome cultures were prepared and scored for selected numerical and morphological abberrations. There was no significant difference in the frequency of chromosomal aberrations between irradiated and unirradiated cells. The fraction of cells S surviving after an exposure to an ultrasound dose of D can be represented by S = exp (-D/Do). Further, Do is shown to depend on the time after exposure at which survival is assayed.

Cell Survival↗
PubMed1978

Translation of procollagen messenger RNA in a cell free system derived from wheat germ: hydroxylation of prolyl residues in the product.

Ribonucleic acid extracted from chick embryo calvaria directs the synthesis of a collagenous product in a cell-free system. A portion of the prolyl residues incorporated into this protein can be hydroxylated in vitro by prolyl hydroxylase as demonstrated by the release of 3H-H20 from 3H-proline and by the direct demonstration of 3H-hydroxyproline in acid hydrolysates of the product. Thirty percent of potential sites become hydroxylated in the in vitro reaction using either cell-free product or an underhydroxylated collagen extracted from chick calvaria. Neither prolonged incubation nor increased levels of enzyme increased the extent of hydroxylation in either substrate.

Cell-Free System↗
PubMed1977

Resolution of ribonucleic acids by Sepharose 4B column chromatography.

Ribonucleic acids were resolved by molecular sieve chromatography on columns of Sepharose 4B. The elution positions of messenger ribonucleic acids were determined by detection of polyadenosine tracts and by support of protein synthesis in a messenger-dependent cell-free system. The elution position of other ribonucleic acid species from the Sepharose 4B was determined by formamide-sucrose density gradient centrifugation. Resolution of ribonucleic acids by this column was not dependent on molecular weight but rather on other properties such as secondary structure or the presence of poly(adenylic acid). The elution profiles of ribonucleic acids on cross-linked Sepharose 4B differed markely from those on conventional Sepharose and appeared to depend on molecular size alone. There was diminished resolution of high molecular weight ribonucleic acids on such columns.

Animals↗
PubMed1977

Chronic polyarthritis associated with hypogammaglobulinemia. A study of two patients.

Two adult patients with hypogammaglobulinemia and chronic synovitis were studied. Synovial tissue and fluid were examined by histologic, virologic, and immunologic methods. The synovium lacked characteristic histologic features of rheumatoid arthritis, and B lymphocytes were absent from the synovial tissue, fluid, and peripheral blood. These 2 patients may represent a form of chronic synovitis produced in the absence of any B lymphocyte response.

Agammaglobulinemia↗
PubMed1977

Hexamethylene bisacetamide induces morphologic changes and increased synthesis of procollagen in cell line from glioblastoma multiforme.

Addition to hexamethylene bisacetamide (diacetyldiaminohexane) to cultures of a malignant mesenchymal cell line derived from a human glioblastoma multiforme induces morphological changes and stimulates the synthesis of procollagen. The morphological changes include cell elongation, an increase of extracellular material with staining properties of collagen by light microscopy, and an increase in extracellular 220-A fibrils by electron microscopy. The rate of procollagen synthesis increased as much as 20-fold, and the ratio of type I:type III procollagen changed, with type I becoming the predominant form. The change in type I:type III ratio is similar to that seen in the maturation of normal fetal to adult connective tissue.

Acetamides↗
PubMed1977

Specificity of initiation of transcription of simian virus 40 DNA I by Escherichia coli RNA polymerase: identification and localization of five sites for initiation with [gamma-32P]ATP.

Simian virus 40 (SV40) DNA I was transcribed with Escherichia coli RNA polymerase in the presence of gamma-32P-labeled ribonucleoside triphosphates in order to investigate the specificity of initiation of in vitro transcription. ATP and GTP served as predominant initiating nucleotides, the former being incorporated about twice as much as the latter. Cleavage of [gamma-32P]ATP-labeled SV40 complementary RNA (cRNA) with T1 RNase followed by homochromatographic analysis of the resultant 5' initiation fragments revealed the presence of four specific initiation fragments 6 to 9 nucleotides in length, designated AI, AII, AIIIa, and AIIIb. By means of hybridization of [gamma-32P]ATP-labeled SV40 cRNA to DNA from specific adenovirus 2-SV40 hybrids and specific restriction endonuclease fragments of SV40 DNA before chromatographic analysis, it was possible to identify and determine approximate localizations of five [gamma-32P]ATP initiation sites on the SV40 genome: one in Hin-G close to the Hin-G-B junction, giving rise to the AII fragment, two in the overalpping fragment Hin-A-Hae-A,giving rise to AI and AIII fragments, and two in the fragment Hin-A-Hae-E, also giving rise to AI and AIII fragments. All five sites either fall within or lie near regions of the genome that are cleaved by S1 nuclease and subject to partial alkaline denaturation. These five sites lie on the minus strand of SV40 DNA and initiate RNAs that are copied in a leftward direction. Cleavage of [gamma-32P]GTP-labeled cRNA with pancreatic RNase liberated three major 5' initiation fragments of short length, GI, GII, and GIII, suggesting the presence of three principal GTP initiation sites.

Adenosine Triphosphate↗