Investigation of Solvent Effect and H-Bonding on Spectroscopic Properties of 1-(3-Amino-6-(2,5-dichlorothiophen-3-yl)-4-phenylfuro[2,3-b]Pyridin-2-yl) Ethenone: Experimental and Computational Study.

The furo[2,3-b]pyridine moiety is an important scaffold for many biologically active compounds, therefore, the spectral data of the derivative 1-(3-Amino-6-(2,5-dichlorothiophen-3-yl)-4-phenylfuro[2,3-b]pyridin-2-yl) ethenone (FP1) were investigated. Analysis of absorption-pH profile and Förster cycle of FP1 revealed that its excited state is more acidic than its ground state ([Formula: see text] < [Formula: see text]). The main fluorescence emission band of FP1 at 480 nm (in hexane) is shifted to longer wavelengths with increasing polarities of solvents. Linear Lippert's plot and linear correlation between bands maxima and Camlet-Taft parameter, α, of the protic solvents indicated efficient intramolecular charge transfer and noticeable H-bonding. Moreover, the disappearance of the absorption band of FP1 at 385 nm in water, along with the noticeable red shift and quenching of the emission band, and the lower lifetime, relative to nonaqueous solvents, indicate the interruption of the furo[2,3-b]pyridine aromatic moiety. In addition, results from the Time Dependent Density Functional Theory (TDDFT) and Molecular Mechanic (MM) calculations were in agreement with experimentally determined spectra of FP1.

The therapeutic use of peritoneal macrophages in infected leukaemic patients.

Ten patients with acute leukaemia and infection unresponsive to antibiotics received single or multiple transfusions of peritoneal cells, mainly macrophages, obtained from donors undergoing peritoneal dialysis for renal failure. In six patients the cultures became negative and the temperature returned to normal and remained there, in two, there was temporary return of the temperature to normal and two patients showed no response. No significant side-effects were encountered. No changes in leukaemic blast cell numbers were seen in any of the patients.

A note on xenogeneic transfusion of macrophages in experimental septicaemia.

Human peritoneal macrophages (M phi) were given intravenously to normal rabbits and rabbits with Escherichia coli septicaemia. No harmful effects were observed during a period of three months following macrophage transfusions and the septicaemia was eradicated in four of five animals. Thus xenogeneic M phi transfusion is feasible and can combat serious bacterial infections.

Effect of electroconvulsive therapy on diabetes mellitus.

Of fourteen patients with diabetes mellitus, eight had complete remission of diabetic symptoms after one or two applications of elctroconvulsive therapy (ECT). In those who benefited the diabetes was of recent onset and non-insulin-dependent. One patient remains free from diabetes 14 years after ECT.

Output of peritoneal cells during peritoneal dialysis.

Peritoneal dialysis provides a good source for the collection of macrophages. Six patients with chronic renal failure undergoing peritoneal dialysis for the first time were studied, and maximum cell egress, mostly macrophages, occurred at 24-48 hours and diminished after 48 hours.

Overcoming some limiting factors in tumour immunotherapy.

Immunotherapy using rat 7s antibodies against plasmacytoma 5563 in C3H mice has been measured carefully. Prior adsorption of antibodies with normal mouse tissues, and supplements of co-optable non-immunized macrophages and lymphocytes enhanced the scope of immunotherapy against established tumours. It is suggested that available co-optable lymphocytes and macrophages are imporant limiting factors in tumour immunotherapy.

Studies of the rat immune response to plasmacytoma 5563 in C3H mice.

Washed lymphocytes from immunized rats showed no reaction against mouse plasmacytoma 5563 in vivo or in vitro.Cell-free lymph from immunized rats was shown to be cytotoxic to the tumour cells in vitro. This effect we have shown to be solely in the 19s fraction after Sephadex G-200 separation.This 19s fraction conferred partial protection to tumour bearing mice when given shortly after transplantation, but had negligible effect against late well established tumour.