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R A Anwar

Publications and source records attributed to R A Anwar.

At least 19 recordsLinked to original sources
PubMed1994

Evidence for the presence of a functional TATA box (ATAAAA) sequence in the gene for bovine elastin.

The wild type sequence (wt; ATAAAA) was mutated and the effects of the mutants were determined by assaying the expression of the chloramphenicol acetyltransferase (CAT)-encoding gene (cat) cloned downstream. The negative mutant (neg; ACGAAA) practically abolished the activities of the 129 bp and the 416 bp elastin promoters in NIH 3T3 and neonatal rat aortic smooth muscle cells, respectively. However, when the positive mutant (pos; TATAAAA) was assayed in parallel experiments, there was enhancement of activity. The TATA box-binding protein (TBP) was shown to bind to the ATAAAA sequence and the retardation of the band was abolished by competition assay using unlabeled wt and pos sequences, but not by the neg mutant. These results provide evidence for the presence of a functional TATA box in the gene for elastin.

Animals↗
PubMed1994

Evidence for a cell-specific negative regulatory element in the first intron of the gene for bovine elastin.

A cell-specific negative regulatory element has been identified in the first intron of the gene for elastin in a region between 442 and 464 bp from the translational start site. This regulatory element functions both when it is located 5' of the promoter and 3' of the chloramphenicol acetyltransferase (CAT) gene. The inhibition is observed both with the homologous elastin promoter and the heterologous SV1 promoter in transient expression experiments using rat aortic smooth-muscle cells. No inhibition was observed with NIH 3T3, Hep G2 and little, if any, with HeLa cells. Cell specificity was further confirmed by DNA mobility shift assays and the position of the negative regulatory element was localized with the use of synthetic duplex oligomers. It is proposed that this negative element plays a significant role in the modulation of the expression of the gene for elastin in the smooth-muscle cells of the aorta during development.

3T3 Cells↗
PubMed1989

Developmental regulation of the mRNAs for elastins a, b and c in foetal-calf nuchal ligament and aorta.

The data presented clearly suggest that relative amounts of mRNAs for elastins a, b and c are developmentally regulated in foetal-calf nuchal ligament and aorta and that this regulation is tissue-specific. In nuchal ligament, at earlier stages of foetal development, the relative amounts of mRNAs for elastins a and b are very low. After the foetal age of about 6 months the relative amount of mRNA for elastin b begins to increase. This is followed by an increase in the relative amount of mRNA for elastin a. In aorta, with increasing foetal age, the relative amounts of mRNAs for elastins b and c increase and decrease alternately. The relative amounts of mRNA for elastin a remain low, with only marginal increases with foetal age. A possible self-aggregation role of elastin a in elastogenesis is proposed.

Animals↗
PubMed1989

Education is not enough: a systems failure in protecting battered women.

A retrospective study of female trauma patients presenting in an emergency department during 1976 and 1977 demonstrated that the introduction of a protocol designed to detect injuries caused by battering increased the identification of battered women from 5.6% of female trauma patients to 30%. An eight-year follow-up study in the same ED demonstrated that only 7.7% of female trauma patients were diagnosed as having injuries secondary to battering. This study suggests that without institutional policies and procedures for detecting and treating victims of domestic violence, many abused women will pass through EDs unidentified and, hence, untreated.

Adult↗
PubMed1987

Primary structures of bovine elastin a, b, and c deduced from the sequences of cDNA clones.

Nucleotide sequence analysis of cDNA clones for bovine elastin revealed the occurrence of three mRNAs for elastin in fetal calf nuchal ligament, encoding three forms of elastins (a, b, and c, of 747, 733, and 713 amino acid residues, respectively). These forms arise as the result of the presence, at a single position, of 102 additional nucleotides in the mRNA for elastin a and of 60 of these nucleotides in the mRNA for elastin b as compared to the mRNA for elastin c. As expected, most lysines occur in pairs, separated by two or three small amino acid residues. However, at two places, lysines occur in groups of three. The occurrence of a group of three lysines followed by a hydrophobic residue (lysine 400, 404, and 407) offers an explanation for the formation of lysinonorleucine. The alignment of amino acid sequences of porcine tropoelastin tryptic peptides with the sequence for bovine elastin a results in the ordering of these tryptic peptides. The analysis of the complete primary structures of elastin a, b, and c provides further insight into the structure-function relations of elastin.

Amino Acid Sequence↗
PubMed1987

The role of the emergency physician in the prevention of domestic violence.

In the United States, every 7.4 seconds a woman is battered by her husband. Of women who present to emergency departments with traumatic injuries, 16% to 30% report that their injuries were secondary to domestic violence. Not infrequently, battered women's medical and surgical problems are treated by ED staff and the women are released without any intervention directed toward the prevention of future battering and/or injury. Protocols are presented that require only minimal reorganization of staffing in EDs to provide essential services directed toward battered women's most serious health problem, chronic victimization.

Adult↗
PubMed1987

A comparative analysis of the amino acid and cDNA sequences of bovine elastin a and chick elastin.

A comparative analysis of the amino acid and cDNA sequences of bovine elastin a and chick elastin shows that there are considerable differences between these proteins. There is evidence that duplication of segments of DNA and gene rearrangement have occurred in the gene for chick elastin as compared with the gene for bovine elastin. The length of the polypeptide chain of elastin in both species is similar. Therefore, the duplications are compensated for by deletions in the gene for chick elastin.

Amino Acid Sequence↗
PubMed1986

UDP-N-acetylmuramoyl-L-alanyl-D-glutamyl-L-lysine synthetase from Bacillus sphaericus: activation by potassium phosphate.

During the course of purification of UDP-N-acetylmuramoyl-L-alanyl-D-glutamyl-L-lysine synthetase, we observed a marked stimulation of the enzymatic activity in the presence of phosphate ions. This activation effect was studied with enzyme purified 979-fold from Bacillus sphaericus. Each salt tested stimulated the activity of the synthetase. The order of activation by different anions was HPO4(2-) greater than Cl- greater than SO4(2-). In every case, the potassium salt gave higher activity than the corresponding sodium salt. The activation in the presence of phosphate was quite pronounced (almost sevenfold with K2HPO4) and occurred at a relatively low concentration. The Ka for K2HPO4 was found to be 3.4 mM and the Hill coefficient was calculated to be 1.0. This would suggest that there is one phosphate-binding site per active centre. The presence of phosphate did not affect either the pH optimum of this enzyme or the optimum concentration of Mg2+ required. The presence of phosphate has little or no effect on the Km of any of the substrates. Thus, it appears that the presence of phosphate changes the enzyme conformation to a catalytically more active form. The activation of this enzyme in the presence of phosphate anion is all the more interesting because phosphate is a product of the reaction catalyzed by this enzyme.

Bacillus↗
PubMed1985

Bovine elastin cDNA clones: evidence for the occurrence of a new elastin-related protein in fetal calf ligamentum nuchae.

Poly (A+) mRNA was isolated from fetal calf ligamentum nuchae and used for the construction of cDNA libraries. A fraction highly enriched in elastin mRNA was used to prepare the cDNA probes for screening the libraries. A 2 kb clone, pRE1, gave the most positive signal in colony hybridization. It hybridized to a mRNA of the same size as reported for elastin mRNAs from chick and sheep. Hybrid-arrested translation showed that translation of mRNAs for proteins other than elastin doublet was not inhibited by pRE1. Southern blot analysis showed that pRE1 has sequence homology with pVE6 and pVE10, which were tentatively identified as elastin-related cDNA clones representing two distinct mRNAs. DNA sequence data from the 5' end of pRE1 show that the translated amino acid sequence is not typical of known elastin sequences but contains some elastin-like sequences. All of this evidence strongly suggests the occurrence in fetal calf nuchal ligament of a mRNA which codes for a previously unknown elastin-related protein.

Amino Acid Sequence↗
PubMed1983

Orthostatic changes in normovolemic children: an analysis of the "tilt test".

Orthostatic changes in pulse rate and blood pressure were assessed on 455 normovolemic children between 4 and 17 years of age who visited emergency departments with a variety of complaints. Blood pressures and pulse rates were measured in the upper extremity with the patient supine, sitting, and standing. The postural changes in pulse rate and blood pressure for age groups 4 to 9 years, 10 to 13 years, and 14 to 18 years were computed, and statistical analyses were performed to identify factors predisposing to changes in pulse rate and blood pressure. In all categories of chief complaint, comparable numbers (average 25.4%) of patients had an increase in pulse rate of greater than 20 beats/min. An average of 10.7% of children in each category had a fall in systolic blood pressure greater than 20 torr. Only increasing body temperature, especially in the youngest children, and diarrhea, particularly if more than 12 hours in duration, predisposed to having a "positive tilt test" using these criteria. The "tilt test" for assessing orthostatic hypotension is of little value in assessing normovolemic children presenting for acute care. A positive test result is very nonspecific.

Adolescent↗
PubMed1983

A longitudinal study of residency-trained emergency physicians.

An annual survey of emergency medicine (EM) graduate physicians from 31 programs was conducted from 1977 through 1979. Results of the 1979 data are presented. Practice patterns show that 96% of the EM graduates are providing patient care, and almost half are working in the states in which they trained. Of those caring for patients, 38.8% practice in an urban location and only 7% work in rural hospitals. Learning new skills and procedures and retaining skills are major problems faced by physicians in rural locations. Other activities of EM graduates include teaching medical students and residents, administration, research, and community emergency medical services. Data are analyzed with attention to long-term commitment to emergency medicine. Implications for manpower needs are suggested.

Emergency Medicine↗
PubMed1983

In vitro translation of elastin mRNA and processing of the translated products and the signal sequence of elastin a.

Chick embryo aorta mRNAs were translated in a gel-filtered reticulocyte lysate. The translated products showed two elastin-related proteins (a and b; relative mass approximately 70 000). The translated elastin a protein was separated essentially free of the b protein by centrifugation and sodium dodecyl sulfate (SDS) - polyacrylamide gel electrophoresis. The a protein was then electroeluted from the SDS-polyacrylamide gel and a partial sequence was determined by automated Edman degradation. The NH2-terminal presequence of the elastin a protein is (formula; see text) The assigned sequence is identical to that reported for the b protein. Translation of chick embryo aorta mRNA in the presence of dog pancreas microsomal membranes segregated the a and b proteins into membrane vesicles and cotranslationally cleaved their respective presequences. The processed a and b elastin proteins were isolated together and NH2-terminal proline positions were determined. These are (formula; see text) These proline positions 4 and 8 are identical to those for NH2-terminal sequence for tropoelastin. This suggests that the signal peptidase removes the 24-residue signal peptide and thus directly generates the tropoelastin sequence, with no NH2-terminal prosequence as the intermediate.

Amino Acid Sequence↗
PubMed1982

A time efficient EMT-A course for first year medical students.

The purpose of the study was to design an EMT-A course for freshman medical students that maximized practical work and minimized lecture hours. A 48-hour required course was given up to 101 members of the first-year class at The Medical College of Pennsylvania. Ten hours of lecture-demonstration time were included. Test scores were comparable to scores of regular EMT-A candidates and medical students who had a full lecture series included in their course. Means of further decreasing the number of hours of the course are discussed. By decreasing the number of curricular hours, it is hoped that medical schools not having EMT-A certification programs in their preclinical years will be encouraged to do so.

Allied Health Personnel↗
PubMed1980

Effect of phosphoenolpyruvate analogs on the activity of enoylpyruvate transferase and the effect of UDP-N-acetylglucosamine on the reactivity of the active site SH group.

Effect of several phosphoenolpyruvate analogs on the activity of enoylpyruvate (phosphoenolpyruvate: UDP-2-acetamido-2-deoxy-D-glucose 2-enoyl-1-carboxyethyltransferase, EC 2.5.1.7) transferase was examined. The results suggest that the phosphoenolpyruvate binding site of the transferase is very similar to that of pyruvate kinase (ATP: pyruvate 2-O-phosphotransferase, EC 2.7.1.40). Evidence is presented to show that the binding of UDP-GlcNAc to the transferase enhances the reactivity of the active site SH group.

Alkyl and Aryl Transferases↗
PubMed1980

Amino acid sequences C-terminal to the cross-links in bovine elastin.

All the desmosine-containing elastolytic peptides of bovine ligamentum-nuchae elastin have now been examined for amino acid sequences C-terminal to the cross-links. In addition, amino acid residues C-terminal to lysine residues in bovine tropoelastin were also examined. No tyrosine C-terminal to cross-links in bovine elastin or C-terminal to lysine in tropoelastin was detected. Apparently all the tyrosine residues C-terminal to lysine residues in pig tropoelastin are replaced with phenylalanine in bovine tropoelastin. All the data presented are consistent with the scheme proposed for the formation of desmosine and isodesmosine cross-links of elastin by Gerber & Anwar [(1975) Biochem. J. 149, 685--695].

Amino Acid Sequence↗