Statistics can mislead.

Discusses serious statistical problems in S. Scarr and R. A. Weinberg's (see record 1977-07996-001) article on 130 Black children adopted by Whites, in which the authors attempted to ascertain the relative contributions of 10 social and 2 biological variables to IQ variance. Corrected statistical analyses show opposing trends for the contributions of nurture and nature. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of ortho-iodo sodium benzoate on hemoglobin-oxygen affinity in normal and ischemic myocardium

The effect of ortho-iodo sodium benzoate (OISB) on the oxyhemoglobin dissociation curve of coronary venous blood was studied in an isolated canine heart preparation perfused at a constant coronary blood flow. Changes in P-50 (millimeters of mercury) [the oxygen tension (pO2) at which hemoglobin is 50% saturated], were used to express hemoglobin-oxygen affinity. Intracoronary infusion of OISB (200, 400 and 800 mg/min) produced a dose-related increase in coronary venous P-50 and a concurrent increase in coronary venous pO2. In addition, OISB produced a significant decrease in heart rate and increase in coronary artery perfusion pressure. During cardiac pacing at 150, 190 and 230 beats/min, OISB (400 mg/min) significantly increased coronary venous P-50, myocardial oxygen exrraction (O2E) and oxygen consumption (MVO2) whereas coronary venous PO2 was not changed. Furthermore, a 5-minute intracoronary infusion of OISB (200 mg/min) during myocardial ischemia produced an increase in O2E, MVO2 and myocardial contractility with little change in coronary venous pO2. These results suggest that acute pharmacological manipulation of the oxyhemoglobin dissociation curve may enhance oxygen release to the myocardium while maintaining the effective driving pressure (as reflected in coronary venous pO2) for diffusion of oxygen to the myocardium.     

The mixed leucocyte-macrophage migration test in actively sensitised and transfer factor-treated Rhesus monkeys. Preliminary observations on HBsAg specific transfer factor

Although the rise in blood copper is associated with onset of the acute haemolytic crisis of chronic copper poisoning in sheep, the sudden fall in erythrocyte glutathione is apparently not due to a direct action of the copper. Moreover the reduced glutathione of the red cells is converted to some form that is not capable of regeneration by the pentose-phosphate mechanism. Only negligible inhibition of the pentose-phosphate enzymes occurs. As the haemolysis proceeds, there is a rapid recovery of erythrocyte glutathione levels, and a marked increase in pentose-phosphate enzyme activity, consistent with influx of young red cells. It seems that the release of copper into blood from liver at the haemolytic crisis is associated with an increase of the oxidative state of the blood, possibly by simultaneous release of other components from the liver.     

Nosocomial pseudobacteremia. Positive blood cultures due to contaminated benzalkonium antiseptic

Pseudomonas cepacia or Enterobacter species or both were isolated from blood cultures of 79 patients in a community hospital between April 1971 and March 1972. No common exposures other than venipuncture correlated with positive blood cultures. Pseudomonas cepacia, Enterobacter, and other Gram-negative enteric bacteria were cultured from aqueous benzalkonium chloride used for skin antisepsis prior to ordinary and blood culture venipuncture. Contamination of blood cultures by organisms from the antiseptic most likely accounted for positive cultures in 35 to 38 patients (92%) with P cepacia. The remaining three patients had repeated blood cultures positive for P cepacia and circumstantial clinical evidence of bacteremia; they may have contracted disease through exposure to the contaminated antiseptic. Substitution of an iodine-alcohol antiseptic abruptly reduced the isolation of P cepacia and Enterobacter.