Spectroscopic studies and antibacterial activities of some new 16-membered octaazamacrocyclic complexes derived from thiocarbohydrazide and pentane-2,4-dione.

A series of macrocyclic complexes of the type [M(C12H20N8S2)X2]; where M=Co(II), Ni(II), Cu(II), Zn(II); X=Cl-, NO3-, CH3COO- has been synthesized by template condensation of thiocarbohydrazide and pentane-2,4-dione in the presence of divalent metal salts in methanolic medium. The complexes have been characterized with the help of elemental analyses, conductance measurements, magnetic measurements, electronic, NMR, IR, EPR and MS spectral studies. The low value of molar conductance indicates them to be non-electrolytes. On the basis of various studies a distorted octahedral geometry may be proposed for all of these complexes. These metal complexes were also tested for their in vitro antibacterial activities against some Gram-positive bacterial strains, i.e., Bacillus subtilis, Bacillus stearothermophilus and two Gram-negative bacterial strains, i.e., Escherichia coli, Pseudomonas putida. The results obtained were compared with standard antibiotics, Chloramphenicol and Streptomycin and found that some of the synthesized complexes show good antibacterial activities as compared to the standard antibiotics.

Effect of quinine therapy on plasma glucose and plasma insulin levels in pregnant women infected with Plasmodium falciparum malaria in Gezira state

To determine if quinine has a metabolic effect during treatment of severe or complicated malaria, we studied its effects on plasma glucose and plasma insulin levels in 150 pregnant women with malaria referred to Madani maternity teaching hospital, Gezira state and 50 healthy pregnant controls. Levels were determined at baseline [day 0] before the start of quinine treatment, after 2 days of treatment [2 hours after the 4th dose] and after 7 days of treatment [day 8]. There was a statistically significant increase in plasma insulin concentrations during the quinine infusion and fall in plasma glucose concentration [P<0.001]. Quinine administered at the recommended dose and rate can disrupt plasma glucose homeostasis although it is still the drug of choice for severe and complicated malaria in Sudan

Cyclin T1 domains involved in complex formation with Tat and TAR RNA are critical for tat-activation.

Tat activates transcription from the human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR) by increasing the processivity of RNA polymerase II. Recently, it has been demonstrated that the cellular kinase CDK9 and its binding partner cyclin T1 are involved in regulating transcriptional elongation and tat-activation. Cyclin T1, CDK9 and Tat bind as a complex to elements in TAR RNA that are required for tat-activation. Here, we used cyclin T1 mutants to define domains in this protein that bind to both CDK9 and Tat and are involved in stimulating tat-activation. The region of cyclin T1 extending from amino acid residues 1 to 263 is necessary for complex formation with Tat bound to TAR RNA and for stimulation of tat-activation in murine cells that are normally poorly responsive to the actions of Tat. In contrast, a smaller region of cyclin T1 was required to bind to CDK9 and stimulate its kinase activity. Recombinant cyclin T1 and CDK9 stimulated both basal and tat-induced in vitro transcriptional elongation from the HIV-1 LTR. The effects of Tat on transcriptional elongation may be mediated by its ability to increase CDK9 phosphorylation of the RNA polymerase II C-terminal domain. These results demonstrate that cyclin T1 interactions with Tat and TAR RNA are critical for activation of HIV-1 gene expression.

Role of the human and murine cyclin T proteins in regulating HIV-1 tat-activation.

Human cyclin T1 markedly stimulates tat-activation in rodent cells which are normally poorly responsive to the effects of Tat. This result suggests that there are likely to be critical differences in the murine and human cyclin T1 proteins. Here, we analyzed the role of the murine and human cyclin T1 proteins in addition to the human cyclin T2a and T2b proteins on regulating tat-activation. Only the human cyclin T1 protein efficiently formed a complex with Tat bound to TAR RNA. This difference in function was due to the presence of a cysteine residue in human cyclin T1 at position 261 rather than a tyrosine or asparagine residue which are found in the murine cyclin T1 protein and the human cyclin T2a and T2b proteins, respectively. A mouse cyclin T1 protein containing a substitution of tyrosine residue 261 with a cysteine residue, was able to interact with Tat and stimulate tat-transactivation in rodent cells. Likewise, substitution of a cysteine residue for an asparagine residue at position 260 of the cyclin T2a and T2b proteins also resulted in their ability to interact with Tat and stimulate tat-activation in rodent cells. The data indicate that a specific residue in the cyclin T proteins is required for their in vitro interaction with Tat and their ability to stimulate in vivo tat-activation.

[Mass screening of colorectal cancer by general practitioners in France: what is the real target population?]. / Le dépistage de masse du cancer colo-rectal par les médecins généralistes en France: quelle est la vraie population cible?

OBJECTIVES: People at high risk of colorectal cancer, due to familial or personal history, or to specific symptoms, are considered not to be concerned by mass screening by Haemoccult test. The aim of this study was to investigate people aged 50 to 74 with high risk of colorectal cancer among general practitioners' practices in the department of Calvados (France). METHODS: A random sample of 200 general practitioners were asked to systematically fill out a questionnaire on Haemoccult II proposal for 50-74 year-old patients for a whole week. RESULTS: Participation rate of general practitioners was 58.5%. According to our findings, 13% of 50-74 years patients are considered not be concerned by mass screening, due to familial or personal history, or to specific symptoms. CONCLUSIONS: Colorectal cancer screening protocol have to be fit to level of risk of colorectal cancer. Involvement of general practitioners in colorectal cancer mass screening allows identification of high risk people who can then be managed with a more suitable screening protocol.