Tobacco and health: What can the medical profession do?

Tobacco consumption, that leads to three million deaths every year of which about one million occur in developing countries is a social evil(1). Tobacco smoke is a complex mixture of as many as 4700 individual constituents including carcinogens, irritants, ciliotoxic substances and poisonous gases. There is no dearth of information about the health hazards to smokers. it has been implicated as a major risk factor in a variety of chronic diseases including cardiac, cerebrovascular, malignant, respiratory and other diseases (2), Most of the smoking related lung diseases (e.g. chronic obstructive lung disease and lung carcinoma) are dose dependent. it is often the cumulative dose of smoking which determines the risk. Parameters like pack-year (PY) have been used to express exposure to tobacco smoke. One PY implies one packet of cigarettes (or 20 gms. tobacco) smoked each day over a course of one year (3). In India the number of cigarettes and bidis per packet is quite variable. A standard packet of cigarette and bidis per packet is quite variable

Health Management Concepts in Lobster Mariculture

Lobsters are considered as highly priced delicacies and command high prices in the domestic and. export markets. Lobster fishety which remained as subsistence fishery till the sixties bas now flourished into a commercial activity earning valuable foreign excbange for the country

Transfer co-efficient for carbon monoxide in sportsmen

The transfer factor (TLCO) and the transfer coefficient (KCO) for carbon monoxide were measured by the single-breath method in eleven non-smoking college sportsmen. The mean transfer factor for whole lung in the college sportsmen was within normal limits when compared to predicted values of European descent; however, the transfer coefficient was high and is thought to be due to a rise in pulmonary capillary blood volume. It is postulated that continuous and prolonged training of sportsmen causes recruitment of pulmonary capillaries and this causes increased capillary blood volume even at rest

Cellular profile of bronchoalveolar lavage fluid in pulmonary tuberculosis

Bronchoalveolar lavage (BAL) has been used to study the immunopathogenesis of several respiratory diseases. The aim of our study was to determine the inflammatory changes occurring at the site of a tuberculous lesion in the lung in children

Persistng alveolitis in miliary tuberculosis despite treatment with short-course chemotherapy

Bronchoalveolar lavages in two patients with miliary tuberculosis have shown lymphocytic alveolitis. A 6-month regimen with an initial intensive 2- month phase resulted in remarkable clinical and radiographic improvement in both. However, bronchoalveolar lavage following treatment has shown that there was a persistence of lymphocytic alveolitis, though with reduced intensity. The significance of the persisting alveolitis, despite treatment, is not known at present. There is also a suggestion that compartment-alisation of lymphocytes may occur in miliary tuberculosis of the lung

Structural studies on MtRecA-nucleotide complexes: insights into DNA and nucleotide binding and the structural signature of NTP recognition

RecA protein plays a crucial role in homologous recombination and repair of DNA. Central to all activities of RecA is its binding to Mg+2-ATP. The active form of the protein is a helical nucleoprotein filament containing the nucleotide cofactor and single-stranded DNA. The stability and structure of the helical nucleoprotein filament formed by RecA are modulated by nucleotide cofactors. Here we report crystal structures of a MtRecA-ADP complex, complexes with ATPS in the presence and absence of magnesium as well as a complex with dATP and Mg+2. Comparison with the recently solved crystal structures of the apo form as well as a complex with ADP-AlF4 confirms an expansion of the P-loop region in MtRecA, compared to its homologue in Escherichia coli, correlating with the reduced affinity of MtRecA for ATP. The ligand bound structures reveal subtle variations in nucleotide conformations among different nucleotides that serve in maintaining the network of interactions crucial for nucleotide binding. The nucleotide binding site itself, however, remains relatively unchanged. The analysis also reveals that ATPS rather than ADP-AlF4 is structurally a better mimic of ATP. From among the complexed structures, a definition for the two DNA-binding loops L1 and L2 has clearly emerged for the first time and provides a basis to understand DNA binding by RecA. The structural information obtained from these complexes correlates well with the extensive biochemical data on mutants available in the literature, contributing to an understanding of the role of individual residues in the nucleotide binding pocket, at the molecular level. Modeling studies on the mutants again point to the relative rigidity of the nucleotide binding site. Comparison with other NTP binding proteins reveals many commonalties in modes of binding by diverse members in the structural family, contributing to our understanding of the structural signature of NTP recognition

Internal water bridge and antiparallel sheet in the structure of benzyloxycarbonyl-L-alanyl-D-phenylalanyl-L-proline monohydrate

Benzyloxycarbonyl-L-alanyl-o-phenylalanyl-L-proline monohydrate, C25H29N3O6.H2O, crystallizes in the orthorhombic space group P212121 with four molecules in a unit cell of dimensions a = 9.594 (9), b = 9.705 (4) and c = 27.9 17 (12) Å. The structure has been refined to an R value of 0.067 for 2046 observed reflections. All the peptide units in the molecule are trans and the prolyl residue is in the conformation. The lone water molecule in the structure is hydrogen bonded to the carbonyl O atom in the C2 - Cγ - exo - Cβ endo conformation. The lone water molecule in the structure is hydrogen bonded to the carbonyl O atom in the benzyloxycarbonyl group and to one of the O atoms in the terminal carboxyl group. This internal water bridge, observed for the first time in a linear peptide, provides a model for water-mediated chain-reversal. An interesting feature of the crystal structure is the presence of an antiparallel sheet involving the alanyl and the phenyl-alanyl residues