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Biomedical subjects

J J Smith

Publications and source records attributed to J J Smith.

8 recordsLinked to original sources
PubMed1979

Noncalcified echinococcal liver cyst.

A large echinococcal cyst containing clear fluid was seen as a lucent defect within the liver on the plain radiograph. It had no fatty or calcific contents. No similar cases could be found in the literature.

Adult↗
PubMed1979

Oxygen consumption by chick embryos exposed to mechanical (shaking) stress.

Stage 34 (8-day) and 41 (15-day) chick embryos (Gallus gallus; in ovo) were exposed (3 min) to two separate amounts of mechanical (shaking) stress. Oxygen consumption determinations, following a temperature equilibration period (60 min), were made on entire, intact eggs using a Warburg apparatus equipped with 130-ml flasks modified to hold the egg. Shaking at 300 excursions per minute (epm) resulted in depressed O2 consumption by stages 34 and 41. Only stage 34 embryos had markedly depressed O2 consumption values when shaken at 100 epm. When exposed to 300 epm and reincubated for either 1, 2, or 4 hr prior to O2 consumption determinations stage 34 embryos, following an early return to control levels exhibited a marked fall in O2 consumption by 4 h reincubation. The stage 41 embryos, on the other hand, demonstrated a gradual rise to control O2 consumption levels by 4 h reincubation. Oxygen consumption has now been shown for the first time in an embryonic system (at two distinct developmental stages) to be functionally impaired by mechanically induced stress.

Animals↗
PubMed1979

Isolation of functionally active acini from bovine mammary gland.

Conditions to obtain high yields of intact acini from lactating bovine mammary glands and certain structural and functional characteristics of isolated acini were investigated. A two-factor experiment with three collagenase concentrations (100, 150, and 200 mg/100 ml) and incubation periods (40, 60, and 90 min) demonstrated that increases in both factors significantly increased net acini yield. Largest amounts of acini obtained, based on content of deoxyribonucleic acid, were 10.3% of the original tissue. Morphologically, fractions consisted primarily of acini or large cell clumps, and nearly all cells excluded trypan blue. Acini cultured in complete nutrient medium incorporated radioactive leucine into proteins. When acini were incubated in medium without supplemental amino acids, specific activity of synthesized proteins was correlated negatively with incubation time. During pulse labeling with radioactive L-leucine over 16 min, true labeling of acinar proteins occurred after 4 min. Sequential kinetics of pulse-chase labeling demonstrated a response pattern unique to the in vitro acinar system. Acinar protein synthesis was inhibited by cycloheximide and strongly stimulated by by 3',5'-cyclic adenosine monophosphate.

Animals↗
PubMed1976

Cell partition. A simple test for lymphocyte sensitisation.

An established method of investigating total surface charge on particulate materials has been applied to the detection of changes in surface charge on macrophages which are induced by supernatants from the interaction of sensitised lymphocytes and appropriate antigen. The method was studied as an alternative to the established but problematical macrophage-electrophoretic-mobility (M.E.M.) test for detecting such changes. This preliminary investigation suggests that the results from subjects with and without malignant disease differ significantly.

Antigens, Neoplasm↗
PubMed1976

pH and the level of calcium in the blood of fetal and neonatal albino rats.

Near-term rat fetuses in utero are acidotic and hypoxic, and have high levels of total serum calcium. In the first hour of postnatal life, pO2 and pH increase and pCO2 and calcium fall. Between 1 and 4 h following birth, respiratory gases vary little, whereas pH continues to rise and calcium further declines. By 4 h, newborns reach normal pH levels but are markedly hypocalcemic. It is suggested that the 'hypercalcemia' of intrauterine life is related to acidosis in utero, and that following birth, the initial fall in serum calcium is associated with the blowing off of CO2 and a concomitant rise in pH. The later decline in circulating calcium is independent of alterations in respiratory gases and relates directly to the final correction of neonatal acidosis.

Animals↗