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Biomedical subjects

S Rahman

Publications and source records attributed to S Rahman.

At least 217 records · Page 12Linked to original sources
PubMed1985

Molecular evolution of the seed storage proteins of barley, rye and wheat.

The major storage proteins (prolamins) of barley, rye and wheat are characterized by the presence of two or more unrelated structural domains, one of which contains repeated sequences. Because of this repetitive structure and their restricted distribution (only in grasses), it has been suggested that the prolamins are of recent origin. Contrary to this hypothesis, we show that parts of the non-repetitive domain of one group of prolamins are homologous with sequences present in a large group of seed proteins from monocotyledonous and dicotyledonous plants; including Bowman-Birk protease inhibitors, cereal inhibitors of alpha-amylase and trypsin, and 2 S globulin storage proteins of castor bean and oil seed rape. This implies an ancient origin for these non-repetitive domains. The origins of the repetitive domains are not known but may lie within the grasses.

Amino Acid Sequence↗
PubMed1984

Hordein-gene expression during development of the barley (Hordeum vulgare) endosperm.

A previous study [Rahman, Shewry & Miflin (1982) J. Exp. Bot. 33, 717-728] showed differential accumulation of the major storage proteins (called B and C hordeins) in developing endosperms of barley (Hordeum vulgare). To determine how this accumulation is regulated, we have studied mRNA fractions prepared from similar endosperms. Hordein-related mRNA species were detected some days before the deposition of hordeins in vivo. The translation products in vivo directed by polyribosomes, polysomal RNA and total cellular RNA showed similar changes in the proportions of the hordein products to those observed in the accumulations of the proteins in vivo. There was a relative increase in one of the subfamilies of B hordeins (called B1 hordein) and a decrease in the second subfamily of B hordeins (B3 hordein) and in C hordeins. The populations of RNA species related to these three groups of hordeins were studied by 'dot hybridization', with specific complementary-DNA probes for B1-, B3- and C-hordein-related sequences. This showed a 10-15-fold increase in sequences related to the B1 hordein during endosperm development, but only a 4-fold increase in sequences related to B3 and C hordeins. These results indicate that the rates of synthesis of hordeins are related to the abundance of their respective mRNA species. The different results observed for the two subfamilies of B hordeins are of interest, since they indicate differential expression of two subfamilies of genes present at a single multigenic locus.

Electrophoresis, Polyacrylamide Gel↗
PubMed1984

Molecular analysis of the effects of the lys 3a gene on the expression of Hor loci in developing endosperms of barley (Hordeum vulgare L.).

The lys 3a gene present in the barley mutant Ris phi 1508 results in an increased content of lysine in the grain. Previous studies have shown that this increase results from a decreased accumulation of hordein and an increase in other more lysine-rich proteins and in free amino acids. We report here a detailed examination of the effects of this gene on the different groups of hordein polypeptides and the mRNAs encoding them. The amounts of the two major groups of hordein polypeptides (B and C hordein ) were reduced to about 20 and 7%, respectively, of those present in the parental variety ( Bomi ), with a greater effect on one of the two subfamilies of B polypeptides. In contrast, the amounts of D hordein polypeptides were increased fourfold. In vitro translations of polysomal and total cellular RNA fractions showed similar effects on the relative amounts of hordein products synthesized. More detailed analyses of the populations of hordein mRNAs were made using specific cDNA clones and hybrid-selection translation, Northern hybridization, and "hybrid-dot" analysis. Only traces of mRNAs for "C" hordein were detected, while the abundances of mRNAs for the two subfamilies of B hordeins were reduced to 40 and 5% of those in Bomi . The amount of mRNA for D hordein was increased twofold. A cDNA clone related to B hordein was used to analyze genomic DNA fractions by Southern hybridization. The lys 3a gene had no effect on either the number (about 10) or the organization of the B hordein genes. These studies clearly demonstrate that the effects of the lys 3a gene on the amounts of the hordein polypeptides are closely related to changes in the amounts of the mRNAs encoding them. Although the exact effect of the gene remains unknown, it is most likely to be either at transcription or on the early processing of the mRNA.

Edible Grain↗
PubMed1984

Reversible neurotoxicity with combined lithium-haloperidol administration.

A case is presented exemplifying continuing concern over lithium-haloperidol interactions even at low to moderate doses. Emphasis is placed on distinguishing between worsening psychosis and neurotoxicity. The role of electroencephalographic diagnosing and monitoring of such reactions is discussed. Possible mechanisms of action and interaction with different neuroleptics are reviewed.

Drug Therapy, Combination↗
PubMed1983

Molecular analysis of a mutation conferring the high-lysine phenotype on the grain of barley (Hordeum vulgare).

We have analyzed the molecular nature of the Riso 56 mutation that occurs in barley. This mutation results in a depression of hordein accumulation in the grain and consequently in a higher overall lysine content. In particular, the amount of B hordein, which is encoded by the complex locus Hor-2, is decreased by about 75% because of the absence of the major components. The synthesis of certain minor polypeptides, with properties similar to the major B hordeins, remains unaffected. Analysis of endosperm RNA, by in vitro translation and hybridization to various cloned cDNAs derived from hordein mRNA, shows that mRNA for the major B hordeins is not present in the endosperm. Hybridization of a B hordein cDNA clone to gel-fractionated restriction digests of mutant and wild-type DNA indicates that at least 85 kb of DNA has been deleted from the Hor-2 locus in the high-lysine mutant.

Amino Acids↗
PubMed1982

[Aprotinin-ACD-blood. II. The effect of aprotinin on the release of cellular mediators and enzymes in banked blood (author's transl)].

The concentration of the toxic mediators histamine and serotonin as well as the activity of lactate-dehydrogenase and alkaline phosphatase in banked blood increase significantly during storage. After initial addition of Aprotinin to ACD-Blood the level of these substances remained almost in normal range. The influence of these toxic mediators on the development of shock lung is discussed.

Alkaline Phosphatase↗
PubMed1981

[Fat embolism as a complication in shock. Clinical and therapeutic aspects (author's transl)].

In 36 patients the changes of the haemostasis in relation to hypovolaemic shock period were studied after polytrauma and or surgical operations. It was shown that a correlation between the hypovolaemic shock period and the degree of haemostatic disorder exists. The significance of this interaction for the manifestation of the fat embolism syndrome was demonstrated in two casuistics. It is concluded that the haemostatic disorder in shock enhances the development of the fat embolism syndrome. As a therapeutic consequence adequate volume substitution beside specific anticoagulation seems to be of utmost importance in the posttraumatic treatment.

Adolescent↗
PubMed1981

Under five's morbidity & mortality in Dacca Medical College Hospital & morbidity pattern at P.G. hospital & Lionhati Health Project.

The present study was carried out in OPD of PGH, LHP., ID and OPD of DMCH in an attempt to identify the major determinants of health, nutritional and environmental problems which are being faced by children below age five in the urban and rural areas of Bangladesh. The mean age of the children who suffer from infectious disease are between 2-3 years old. Children between 1 and 2 year suffer from acute disease and die frequently. Female children attend less in these centres than the fellow male children. Due to socio-economic reasons, traditional joint family system is changing to nuclear type. Static health care institutions are less utilised by rural people. Educated fathers seek care quickly. Low income groups attend more in DMCH (OPD). Mean family size above 6. The sleeping rooms are overcrowded. Immunization is not popular in rural areas. Rural women receive less care related to pregnancy, childbirth and puerperium. Height and weight of these children however, are similar to the national nutrition survey results. The leading cases of morbidity and mortality are from infectious diseases. The study gives an account of health status of rural and urban community.

Bangladesh↗
PubMed1979

[The treatment of haemorrhagic complications due to disturbance of platelet function after operations with extracorporal circulation (author's transl)].

The preoperative selective blood cell separation followed by the postoperative platelet autoransfusion could prevent the exhaustion of platelet function by operations with extracorporal circulation. The postoperative blood loss could be reduced by about 57%. This method can be recommended specially in cases of increased platelet traumatization after long time perfusion. Partial disturbances of platelet function after operations with ECC can also be favourably influenced by infusion of homologous phospholipid (Fibraccel). The postoperative blood loss could be reduced by about one third. This method is beneficial in open heart surgery with short perfusion times due to its little technical expenses.

Aortic Valve↗