Pathology of chronic Bolivian hemorrhagic fever in the rhesus monkey

Gross and microscopic lesions of Bolivian hemorrhagic fever (BHF) are described in 10 rhesus monkeys that survived from 30 to 78 days after subcutaneous inoculation with a dose of 10(3) plaque-forming units (PFU) of Machupo virus, a dose which produces a severe and generally fatal disease. Six of the monkeys had been given low doses of homologous immune globulin when initial signs of infection appeared. Monkeys exhibited clinical signs in two phases. The initial signs of acute infection which began to appear about 1 week following inoculation included: diarrhea, depression, anorexia, dehydration, and skin rash. The survivors of this early phase of the illness usually showed improvement before relapsing into the second (or chronic) phase, which was characterized clinically by central nervous system disturbances including incoordination, tremors, convulsions, paresis, and muscle atrophy. Microscopic lesions were similar in both immune globulin-treated and untreated animals. These included widespread lymphoreticular infiltrates in the walls and adventitia of blood vessels of the brain, spinal cord, pancreas, intestine, liver kidney, adrenal, parathyroid, heart, and skeletal muscle. Diffuse lymphocytic infiltrates not confined to the vascular or perivascular tissues were present to a variable degree in many of these and other organs. Several monkeys exhibited lymphocytic inflammation of the choroid, meninges, peripheral nerves, and ganglia.

Purification and properties of a carboxylesterase from the liver of tiger shark (Galeocerdo cuvier)

A procedure is described for the purification of a carboxylesterase from shark liver, using a chloroform-acetone powder prepared from the liver as the starting material. The yield of purified enzyme is approximately 50 mg from 530 g of chloroform-acetone powder. The preparation is electrophoretically homogeneous. Active-site titrations with paraoxon gave an equivalent weight of approximately 83 000. The molecular weight, found from sedimentation equilibrium experiments, is approximately 80 000. There is no evidence of any association or dissociation of this species. The enzyme shows a marked preference for aryl esters over alkyl esters, in contrast to other carboxylesterases so far studied. The amino acid composition of the purified enzyme is reported.

Carboxylesterases (EC 3.1.1). Purification and titration of chicken, sheep, and horse liver carboxylesterases

Chicken, sheep, and horse liver carboxylesterases have been purified by procedures involving ammonium sulfate fractionation, ion-exchange chromatography and gel filtration on Sephadex. The actual yields of the procedures described were as follows: chicken, 1 g from 2 kg of liver powder (chloroform-acetone); sheep, 200 mg from 400 g of powder (chloroform-acetone); horse, 230 mg from 800 g of powder (acetone). The purified enzymes are free of non-carboxyl-esterase protein as shown by gel electrophoresis, although they do contain electrophoretic variants. The equivalent weight of the chicken enzyme is 67,000 based on titration with p-nitrophenyl diethyl phosphate or bis(p-nitrophenyl) phosphate, whereas those of the sheep and horse enzymes are similar to 69,500 and similar to 70,000, respectively, based on titration with p-nitrophenyl dimethylcarbamate.

Carboxylesterases (EC 3.1.1). Amino acid composition of liver carboxylesterases

The amino acid compositions of the carboxylesterases from chicken, ,orse, ox, sheep, and pig livers are reported and compared. As would be expected for this homologous series, the compositions show a general similarity. However, there are some significant differences, but the degree to which particular pairs of enzymes differ is consistent with the evolutionary history of the species from which they were isolated.

Effects of low humidity on small premature infants in servocontrol incubators. I. Decrease in rectal temperature

19 small premature infants in servocontrol incubators, whose abdominal skin temperature was 36.0 +/- 0.3 degrees C, were subjected to alternate high- and low-humidity environments. With low humidity, rectal temperature dropped significantly below abdominal skin temperature. Skin was the predominant site of evaporative heat loss. The temperature was lower on naked skin than on an area covered by adhesive tape. Thus, servocontrol with low humidity increases evaporative heat loss and engenders a cycle of events that results in paradoxical body temperature decrease as the incubator temperature increases.

New York doctors and London medicines, 1677

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Host Pathogen Relations in Powdery in Mildew of Barley II. Changes in Respiratory Pattern

The histological natUl'e of resistance of barley seedlings to infection hy EI'!l8illhe rrl'wninis val'. hOl'de'i is woll understood. Infootion b~' this obligato pal'asito causos marked bioehemical changes in the hosL These changos al'e expressed in an increased l'ospimtory rate. The pattei'll of l'oHpirator,Y ehallgo is differont. and typical for tho varietal typos tested and may be correlated with the ebsorvecl histological changes. This inoreasod respimtion may woll he duo to t.he formatioll, oit.hor by t.ho pathogen or by tho host pathogen oombination, of an agellL which uncouples diroetly 01' indirectly the coneomitant phosphorylations normally limiting tho l'cRpiratory rate.