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Biomedical subjects

M D Altschule

Publications and source records attributed to M D Altschule.

5 recordsLinked to original sources
PubMed1979

"The colouring substance of blood.".

Over a century ago, Stokes wrote on the oxidation and reduction of "the colouring substance of the blood." The mechanisms that govern the binding of oxygen to hemoglobin have been defined in even greater detail and higher orders of accuracy, even to the ends of the oxyhemoglobin dissociation curve. The Bohr effect has ceased to be a reduction in the affinity of hemoglobin for oxygen due to an increasing hydrogen ion concentration and according to a mere logarithmic equilibration constant. The constant has become a variable, subject to the interactions of temperature, carbon dioxide, organic phosphate, and ionic concentrations. This interdependence of so many variables has rendered the once inaccurate, but precise prediction of the effect of tht, well beyond the means of the average physician managing the treatment of a sick patient.

Biological Transport↗
PubMed1978

Studies on rheomelanins. V. Hemolysis associated with the transformation of catechol into rheomelanin in human blood.

Incubation of 2 mg amounts of catechol in 5 ml samples of heparinated blood plasma from four subjects at 38 degrees C for 24 h produced plasma-soluble rheomelanins. These solutions had the brown color and the yellow-green fluorescence in ultraviolet light of 366 nm of other rheomelanins. Their differential ultraviolet and visible spectra showed a rheomelanin absorption maximum at 344 nm. Paper chromatograms of the rheomelanin-plasma solutions in 5% methanol-95% water showed elongated spots of rheomelanins with RF values of 0.82, on Whatman No. 1 paper. Using heparinated distilled water adjusted to pH 7.4 with sodium bicarbonate instead of human blood plasma gave markedly different findings from those obtained with the plasma rheomelanin solutions. Incubation of 4 mg amounts of catechol in 10 ml samples of heparinated whole blood from four subjects for 24, 32 and 48 at 38 degrees C produced rheomelanins as found in the plasma separated from the blood after incubation. The differential ultraviolet and visible spectra of these solutions revealed hemolysis caused by the catechol rheomelanins; this was more marked with longer incubations. The hemolysis was manifested by two absorption peaks at about 270 and 400 nm. Paper chromatography revealed the brown elongated spots of catechol rheomelanins with an RF value of 0.82. Other spots owing to the products of hemolysis were also present.

Catechols↗
PubMed1977

Bad law, bad medicine.

In this Comment, Dr. Altschule contends that in a variety of ways the American legal system currently is endangering the existence of positive physician-patient relationships, which are essential to the effective practice of medicine. First, he contends, physicians are exposed to an excessively high risk of liability for malpractice, and as a result must substitute the use of "defensive," often unnecessary laboratory tests for reliance on their own sound medical judgment. Second, the confidentiality of communications between physicians and patients is receiving inadequate legal protection; therefore, patients often are hesitant to reveal aspects of their medical history that may be critical to their case. Third, the federal government, by its medically inappropriate attempts to ban drugs that do not meet certain federal "safe and effective" standards, and to ban food additives that fail to pass certain federally controlled tests aimed at determining whether the additive causes cancer, is making it increasingly difficult for physicians to prescribe substances that may be of great value to their patients. The author warns that our society's failure to substantially alleviate such problems is likely to lead to an inferior brand of medical practice.

Animals↗