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Biomedical subjects

A K Banerjee

Publications and source records attributed to A K Banerjee.

At least 163 records · Page 9Linked to original sources
PubMed1993

Transcriptional activity and mutational analysis of recombinant vesicular stomatitis virus RNA polymerase.

The 241-kDa large (L) protein of vesicular stomatitis virus (VSV) is the multifunctional catalytic component of the viral RNA polymerase. A protocol has been developed for the synthesis of recombinant L protein that will support viral mRNA synthesis in vitro. COS cells were transfected with a transient expression vector (pSV-VSL1 [M. Schubert, G. G. Harmison, C. D. Richardson, and E. Meier, Proc. Natl. Acad. Sci. USA 82:7984-7988, 1985]) which contains the simian virus 40 late promoter for the transcription of a cDNA copy of the L protein of the Indiana serotype of VSV. Cytoplasmic extracts of these cells efficiently transcribed VSV mRNAs in vitro in conjunction with N protein-RNA template purified from virus and recombinant phosphoprotein synthesized in Escherichia coli. mRNA synthesis was completely dependent upon addition of both bacterial phosphoprotein and extracts from cells transfected with the L gene. Extracts from mock-transfected cells or from cells transfected with the expression vector alone did not support VSV RNA synthesis. RNA synthesis was proportional to the concentration of cell extract used, with an optimum of 0.2 mg/ml. Rhabdoviruses and paramyxoviruses contain a highly conserved GDNQ motif which was mutated in the transfected L gene. All constructs with mutations within the core GDN abrogated transcriptional activity except for the mutant containing GDD, which retained 25% activity. Conserved amino acid changes outside of the core GDN and changes corresponding to other paromyxovirus and rhabdovirus L proteins retained variable transcriptional activity. These findings provide experimental evidence that the GDN of negative-strand, nonsegmented RNA viruses is a variant of the GDD motif of plus-strand RNA viruses and of the XDD motif of DNA viruses and reverse transcriptases.

Amino Acid Sequence↗
PubMed1993

Multicentric gliomas: report of 2 cases.

Two cases of multicentric gliomas with long survival are reported. One patient underwent multiple surgical procedures while another had two separate surgical procedures at the same time. Presence of calcification of CT scan in one case raised suspicion for a preoperative diagnosis of oligodendroglioma. Lack of direct continuity or subarachnoid enhancement on CT scan and low histological grade of the tumours suggested their primary multicentric origin. The incidence of multicentric gliomas in our experience is 0.4% amongst 500 glial tumours over a period of eight years.

Adult↗
PubMed1993

Acidic domain of the phosphoprotein (P) of vesicular stomatitis virus differentially interacts with homologous and heterologous nucleocapsid protein (N).

The homologous and heterologous interactions between the nucleocapsid protein N and the phosphoprotein P of New Jersey and Indiana serotypes of vesicular stomatitis virus were studied. SP6 derived N and P mRNAs were cotranslated in rabbit reticulocyte lysate and the complexes formed thereof were analyzed by 7.5% nondenaturing polyacrylamide gel electrophoresis. P protein of VSV(NJ) has two binding sites for homologous N protein: One located within the C-terminal 11 amino acids (within domain III) is responsible for the formation of five specific complexes while the other site, which spans the acidic domain I, is necessary for the formation of the sixth complex only. In contrast, P(IND) does not form the sixth complex when interacted with homologous N protein. Interestingly, P(NJ) forms only complexes 1 to 5 when it interacts with N(IND). The above results suggest that the complex 6 formation or domain I interacting site is NJ-serotype specific. Two chimeric P proteins were made using heterologous domains I and II/III of the P proteins of both serotypes. The soluble interaction of the chimeric proteins with the N protein supported the observed serotype specific interactions. The chimeric P proteins bound with equal efficiency with N-RNA template of both serotypes. These results strongly suggest that the acidic domain I of the P protein differentially interacts with homologous and heterologous N proteins. The biological significance of these findings is discussed.

Animals↗
PubMed1993

Oxygen desaturation during endoscopy in the elderly.

Arterial oxygen desaturation during oesophago-gastro duodenoscopy (OGD) is well recognised. It has been suggested that severe desaturation (greater than 7%) may predispose patients with cardiopulmonary disease and the elderly to cardiac arrhythmias. During OGD, of 106 elderly patients 26 developed ventricular and/or supraventricular ectopics, but these were not related to the degree of oxygen desaturation induced in this study. Apart from one episode of vasovagal syncope, which responded to intravenous atropine, no serious arrhythmias were recorded. Arterial oxygen desaturation during OGD was easily preventable with oxygen administration via nasal cannulae and was not associated with any adverse haemodynamic effects. Continuous cardiac and oxygen saturation monitoring should be routine practice in order to identify such problems.

Age Factors↗
PubMed1993

Mortality profile in trauma victims.

To assess the mortality incidence among trauma victims a one year prospective study was conducted on all patients admitted with physical trauma. The causes of death amongst trauma victims comprised road traffic accident (44.71%), thermal injuries (19.71%), domestic causes (11.54%), agriculture related injury and criminal violence (9.61% each), fall of construction workers (2.4%), collapse of buildings and train accidents (0.96% each) and industrial injury (0.48%). Mortality was highest among victims with multiple injuries (41.35%). The mortality rate increased in direct proportion to increase in transportation time and injury severity score.

Accidents↗
PubMed1993

Mortality profile in trauma victims.

To assess the mortality incidence among trauma victims, one year prospective study comprising all patients admitted in Rajendra Hospital, Patiala, Punjab with physical trauma was undertaken. Road traffic accidents were the commonest cause of trauma-death followed closely by thermal injury. Mortality was highest among victims of multiple injuries. The mortality rate increased in direct proportion to increase in transportation time and Injury Severity Score (ISS). We advocate some simple preventive and regulatory steps to lower the mortality incidence in trauma cases.

Accidents↗
PubMed1992

A six year prospective study of fibrinogen and other risk factors associated with mortality in stable claudicants.

A total of 333 patients with stable intermittent claudication at recruitment were followed up for 6 years to determine risk factors associated with subsequent mortality. Cardiovascular diseases were the underlying cause of death in 78% of the 114 patients who died. The strongest independent predictor of death during the follow-up period was the plasma fibrinogen level, an increase of 1 milligram being associated with a nearly two-fold increase in the probability of death within the next 6 years. Age, low ankle/brachial pressure index and a past history of myocardial infarction also increased the probability of death during the study period. The plasma fibrinogen level is a valuable index of those patients with stable intermittent claudication at high risk of early mortality. The results also provide further evidence for the involvement of fibrinogen in the pathogenesis of arterial disease.

Aged↗
PubMed1992

Phosphorylation by cellular casein kinase II is essential for transcriptional activity of vesicular stomatitis virus phosphoprotein P.

We have previously shown that phosphorylation of vesicular stomatitis virus (VSV) phosphoprotein P by cellular protein kinase activity is an essential prerequisite for its transcriptional function. We have now purified this protein kinase by monitoring its ability to phosphorylate bacterially expressed, unphosphorylated P protein. Biochemical studies showed that the kinase is indistinguishable from casein kinase II, a ubiquitous cyclic AMP-independent protein kinase present in a wide variety of eukaryotic cells and tissues. Functional VSV transcription could be reconstituted with viral L protein, N-RNA template, and P protein phosphorylated by either purified cellular protein kinase or purified casein kinase II. The unusual role of casein kinase II in the transcription process of a nonsegmented negative-strand RNA virus would have important implications in host-virus interactions and antiviral therapy.

Capsid↗
PubMed1992

Surgical treatment of hidradenitis suppurativa.

The management of hidradenitis suppurativa is frequently unsatisfactory. No method satisfies all requirements for the ideal treatment--quick healing, no hospital admission, minimal patient inconvenience and low recurrence--but greater awareness of the strengths and weaknesses of existing methods should lead to improved management. Good reports of the relative cure rates of the different surgical options are scarce and controlled trials non-existent, but existing evidence is reviewed critically and summarized. The operation of choice in most instances is wide local excision and healing by secondary intention.

Hidradenitis Suppurativa↗
PubMed1992

Relationship between eye and skin irritation in rabbits using a series of textile fiber finishes.

A series of 76 fiber finishes, typically composed of blends of lubricants, emulsifiers, antistatic agents and fatty acid soaps, were tested in rabbits to determine both the eye and the skin irritation potential. Each finish was classified as being either non-, slightly, mildly, moderately or severely irritating to the target tissue during a 48-h post-treatment period. Seven (9.2%) of the finishes tested were severely irritating to both the skin and the eye; two (2.6%) were determined to be non-irritating to both tissues. While occasionally finishes produced equal degrees of damage resulting in similar irritancy classifications, seven (9.2%) finishes were found to be severely irritating to the skin without producing any irritation in the eye. Conversely, one finish was found to be a severe eye irritant without producing any skin irritation. The suggested use of the skin irritation data to predict the ocular reaction needs to be carefully examined, particularly with materials such as these fiber finishes. The prediction that a severe skin irritant is also a severe eye irritant was demonstrated to be in error with 8 of 75 (10.5%) of the finishes studied. Further, there is little predictive association between the skin and eye irritation for these compounds.

Animals↗
PubMed1992

RNA editing in the phosphoprotein gene of the human parainfluenza virus type 3.

RNA editing of the human parainfluenza virus type 3 (HPIV3) phosphoprotein (P) gene was found to occur for the accession of an alternate discontinuous cistron. Editing occurred within a purine-rich sequence (AAUUAAAAAAGGGGG) found at the mRNA nucleotides 791-805. This sequence resembles an HPIV3 consensus transcription termination sequence and is located at the 5'-end of the putative D protein coding sequences. Editing at an alternate site (AAUUGGAAAGGAAAGG), mRNA nucleotides 1121-1136, for accession of a conserved V cistron, which is present in a number of paramyxovirus P genes, was not found to occur in HPIV3. In contrast with many other paramyxoviruses, editing was indiscriminate with the insertion of 1-12 additional G residues not present in the gene template. RNA editing was found to occur in both in vivo (HPIV3 infected cells) and in vitro (purified nucleocapsid complexes) synthesized mRNAs. Further, the in vitro prepared mRNA was edited regardless of whether the nucleocapsid complexes were transcribed in the presence or absence of uninfected human lung carcinoma (HLC) cell lysates. These results support the notion that RNA editing appears to be exclusively a function of viral proteins.

Amino Acid Sequence↗