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Biomedical subjects

A Marcus

Publications and source records attributed to A Marcus.

At least 19 recordsLinked to original sources
PubMed1991

Comparative localization of three classes of cell wall proteins.

The localization of the cell wall proline-rich proteins (PRPs), and the gene expression of the cell wall glycine-rich proteins (GRPs) and the hydroxyproline-rich glycoproteins (HRGPs) were examined in several dicot species. The PRPs are accumulated in the corner walls of the cortex where several cells are joined together and in the protoxylem cell walls of 3-day-old soybean root. In 1-month-old soybean plants, the PRPs are specifically deposited in xylem vessel elements of the young stem, and they are accumulated in both phloem fibers and xylem vessel elements and fibers of the older stem. Likewise, the PRPs are localized in xylem vessel elements and fibers in tomato, petunia, potato and tobacco stems. They are also found in outer and inner phloem fiber cell walls of tomato stem and in outer phloem fiber cell walls of petunia stem. The gene expression of the HRGPs and the GRPs is developmentally regulated in tomato, petunia and tobacco stems. HRGP mRNAs are abundant in outer and inner phloem regions, while GRP mRNAs are present mostly in primary xylem and in the cambium region. Immunocytochemical localization showed that the GRPs have a localization pattern similar to that of the PRPs in tomato, petunia and tobacco stems.

Amino Acid Sequence↗
PubMed1991

[Development-dependent diagnosis in two children with a rare "combined disorder of school readiness" in accordance with ICD-10, F81.3].

The new category (ICD-10) of mixed disorder of scholastic skills (F81.3) includes the combination of specific reading and spelling disorders with specific disorder of arithmetical skills and the combination of specific spelling disorder with specific disorder of arithmetical skills. We could demonstrate such combinations of specific developmental disorders in two children. In addition to diagnostic approaches with standardized testing procedures we used a model that is based on the steps in the development of specific skills. This method can be helpful in determining what kinds of intervention would be most appropriate. Both children with mixed disorders of scholastic skills also had psychiatric disorders.

Achievement↗
PubMed1990

Mortality and air pollution in London: a time series analysis.

The relation between air pollution and mortality in London was examined for the winters of 1958-1972. The data exhibited a high degree of autocorrelation, requiring analyses using autoregressive models. There was a highly significant relation between mortality and either particulate matter or sulfur dioxide (after controlling for temperature and humidity), both overall and in each individual year. Graphic analysis revealed a nonlinear relation with no threshold, and a steeper exposure-response curve at lower air pollution levels. In models with both pollutants, particulate matter remained a significant predictor with about a 10% reduction in its estimated coefficients, while sulfur dioxide was insignificant, with a large drop in its estimated coefficient. The authors conclude that particulates are strongly associated with mortality rates in London, and the relation is likely causal.

Air Pollution↗
PubMed1990

Intact stones or fragments? Potential pitfalls in the imaging of patients after biliary extracorporeal shock wave lithotripsy.

Ultrasound is used after extracorporeal shock wave lithotripsy of gallbladder stones to assess fragmentation. In many patients with apparently successful fragmentation, the posttreatment studies show an intraluminal, echogenic focus within the gallbladder, with posterior acoustic shadowing characteristic of an intact stone. Cholesterol gallstones were fragmented in vitro by means of lithotripsy, and the sonographic appearance of the fragmented stones was followed up over time to study factors that might affect the process. After lithotripsy, fragments settled and produced an echogenic focus with posterior shadowing indistinguishable from the appearance of an intact stone. These experimental observations led to the development of a clinical maneuver to overcome the diagnostic pitfalls posed by the reaggregation of stone fragments in situ. This rollover maneuver helps distinguish between intact stones and fragments, and prevents both diagnostic errors in follow-up and unnecessary retreatment.

Cholelithiasis↗
PubMed1990

Effects of age, neuropsychological impairment, and medication on regional cerebral blood flow in schizophrenia and major affective disorder.

Reports of abnormalities of regional cerebral blood flow (rCBF) in patients with schizophrenia and major affective disorder are contradictory. To gain a better understanding of the possible sources of these contradictions, the rCBF and neuropsychological functioning of 15 schizophrenics, 15 patients with major affective disorder, and 15 age-matched controls were studied. No group differences in overall rCBF, percent frontal deviation in flow, or rCBF asymmetries were observed. Both overall rCBF and percent frontal deviation of rCBF were reduced with greater age and with increasing neuropsychological impairment. Dosage of neuroleptic medication was associated with reduced whole brain flow, not with percent frontal deviation flow. Previously reported differences in the resting rCBF of schizophrenics might be more closely related to the age of the subjects and to their neuropsychological impairment rather than the inherent progression of the disorder.

Adult↗
PubMed1990

[Evaluation of a transitional group home for psychiatric patients during and after adolescence].

A report is given on a 6-year follow-up study of a project involving outpatient treatment of adolescents and young adults (16-21 years of age) coupled with group living following inpatient treatment for psychiatric disorders. During the period studied 45 of the 53 participants completed treatment. The mean duration of treatment was 46 weeks for both the group with and without psychotic symptoms.

Adolescent↗
PubMed1989

Ribosome binding to inosine-substituted mRNAs in the absence of ATP and mRNA factors.

Incubating ribosomes and eukaryotic initiation factor eIF3 with an inosine-substituted mRNA (where the mRNA secondary structure is strongly reduced) in the absence of ATP and other protein synthesis factors produces a 40 S ribosome.mRNA complex. When Met-tRNAMeti and eIF2 are added, a 60 S ribosome subunit attaches forming an 80 S ribosome.mRNA complex. ATP and the three mRNA factors, eIF4B, cap-site factor, and eIF4A, strongly stimulate the attachment of the 60 S subunit. In the absence of Met-tRNAMeti, the 60-S subunit does not attach, and adding ATP and the mRNA factors inhibits the accumulation of 40 S ribosome.inosine mRNA complexes. These results indicate that a 40 S ribosome, probably in a complex with eIF3, has an intrinsic capacity to attach to mRNA. Further, they suggest that Met-tRNAMeti may interact in a subsequent step to stabilize the 40 S ribosome.mRNA complex and allow the attachment of a 60 S ribosome subunit. Although seen most clearly with the inosine-substituted mRNAs, the 40 S ribosome reaction is also obtained with "guanosine" mRNA. A 40 S ribosome attaches to guanosine mRNA without ATP and mRNA factors when an incubation mixture containing ribosomes, eIF3, and mRNA is fixed with glutaraldehyde. In addition, a 40 S ribosome.guanosine mRNA complex can be obtained without glutaraldehyde in incubations containing ATP and the three mRNA factors in the absence of Met-tRNAMeti. The latter reaction is limited because of the instability of the 40 S ribosome.mRNA complex in the absence of Met-tRNA. Nevertheless, its authenticity is indicated by its full dependence upon ATP and the three mRNA factors. The lack of factor requirement for the formation of 40 S ribosome complexes with inosine-substituted mRNAs indicates that ATP and the three mRNA factors function primarily to unwind the secondary structure of a guanosine mRNA. Data relevant to a role for ATP in facilitating ribosome migration on an mRNA are also discussed.

Adenosine Triphosphate↗
PubMed1989

Characterization of two soybean repetitive proline-rich proteins and a cognate cDNA from germinated axes.

We have resolved and analyzed two proline-rich proteins isolated from the walls of soybean cells in culture. The proteins are similar in amino acid content, containing 20% proline, 20% hydroxyproline, 20% lysine, 16% valine, 10% tyrosine, and 10% glutamate. The proteins undergo a rearrangement or a limited cleavage in dilute NaOH, but are otherwise remarkably stable to a high concentration of alkali. We have cloned and sequenced a cDNA from soybean axes germinated for 31 hours (1A10-2) coding for a protein that closely corresponds in its amino acid content to that of the proline-rich proteins. The cDNA sequence predicts a decameric repeat of Pro-Pro-Val-Tyr-Lys-Pro-Pro-Val-Glu-Lys. Consequently, this class of proteins is referred to as repetitive proline-rich proteins, i.e., RPRP2 and RPRP3. We have also analyzed RNA gel blots with probes that discriminate between the new cDNA clone and a related cDNA previously reported [SbPRP1; Hong, Nagao, and Key (1987). J. Biol. Chem. 262, 8367-8376]. Messenger RNAs from young seedlings and from soybean suspension cultures correspond primarily to the new RPRP clone (1A10-2), whereas the predominant mRNA accumulating later in the roots corresponds to SbPRP1.

Amino Acid Sequence↗
PubMed1989

Somatic findings in children and adolescents with anorexia nervosa.

94 patients (mean age 15,4 years) with anorexia nervosa were investigated. We found cardiovascular parameters in correlation with body weight. ECG-changes had no connection with weight and concentration of potassium. Pulse and systolic blood pressure decreased, concentration of urea and SGOT and SGPT increased with weight decreases. Compared with the results of the adults of Fichter (1985), pulse and blood pressure changed more often, whereas the concentration of potassium often rested unchanged. Therapy with neuroleptics calls for ECG-controls. Interesting was the finding that we found less raised levels of cortisol in the group with extremely low weight on admission.

Adolescent↗
PubMed1988

A hydroxyproline-rich protein in the soybean cell wall.

A cDNA clone that hybridizes to an mRNA (1A10) that accumulates to a substantial level in the axis of the germinating soybean seed was sequenced. The amino acid sequence of the clone indicates an almost perfect repeat of Pro-Pro-Val-Tyr-Lys resulting in a protein containing 40% proline and lacking serine and histidine. On the likelihood that such a protein might be a hydroxyproline-rich cell-wall glycoprotein (HRGP), cell walls of a soybean cell culture were extracted by procedures used to obtain soluble basic cell-wall glycoproteins, and the proteins were fractionated and purified. A 33-kDa protein (and possibly a 28-kDa protein) was obtained that has an amino acid distribution similar to that of the cDNA clone. The protein lacks histidine and serine and contains 20% hydroxyproline and 20% proline. The HRGP is thus distinct both in its amino acid content and in its pentameric repeat of Pro-Pro-Val-Tyr-Lys, with half of the prolines being hydroxylated.

Amino Acid Sequence↗
PubMed1988

Workplace smoking policies: attitudes of union members in a high-risk industry.

We surveyed members of a medium-size national union representing workers in high-risk industries to assess workers' support for union and company programs to help smokers break the habit and policies that restrict smoking. Two surveys were conducted that involved 690 respondents in 1984 and 593 respondents in 1985. Respondents overwhelmingly (82%) favored restrictions on smoking in the workplace but less than half agreed that companies or unions should be concerned about workers smoking off the job. For both smokers and nonsmokers, beliefs that cancer has specific causes and can be prevented strongly predict support for workplace smoking control policies. Exposure to company occupational health training also influenced smokers and nonsmokers to support selected smoking control policies. These and other findings led to the conclusion that: (1) educating workers about cancer may promote support for smoking control policies, and (2) smoking control policies are more acceptable in the context of a strong company health and safety program.

Attitude↗
PubMed1986

A wheat germ cap-site factor functional in protein chain initiation.

Component C1 from wheat germ, a factor that functions in attaching ribosomes to mRNA, has been resolved into a fraction that does not bind to m7GDP-agarose (referred to as eIF4B) and one that binds and is eluted specifically by m7GDP. Both components are required for the attachment of ribosomes to [3H]methyl-labeled reovirus RNA and for the translation of a number of mRNAs, including the noncapped RNA of satellite tobacco necrosis virus. The component that binds to m7GDP-agarose, referred to as CSF (cap-site factor), contains primarily proteins of Mr 24,000, 26,000, and 75,000. Crosslinking studies with oxidized [3H]methyl-labeled reovirus RNA show that one of the lower molecular weight polypeptides of CSF interacts specifically with the 5'-cap of the mRNA in the absence of any other components. Incubation of component C1 and eIF4A in the presence of ATP results in the additional crosslinking of a 51- and a 65-kDa protein. In the absence of eIF4A, there is only the crosslinking of the lower molecular mass polypeptide (24 or 26 kDa). Attempts to reconstitute the C1 reaction with CSF and eIF4B result in a considerably diminished reaction. Crosslinking of eIF4A, however, is obtained in an incubation containing only CSF and eIF4A, suggesting that CSF may bring about an initial interaction of eIF4A with the 5' end of the mRNA.

Adenosine Triphosphate↗