Geomicrobiological leaching of tin minerals by Thiobacillus ferro-oxidans and organic agents

Laboratory investigations confirm that it is possible to leach tin from synthetic minerals like stannite, kesterite, stannoidite, herzenbergite, ottemannite and berndtite, and from natural tin minerals which include stannite, cassiterite and varlamoffite, in the presence of Thiobacillus ferrooxidans, and with organic agents of biological origin, especially oxalic acid and oxalic-citric acids mixture. Over a leaching period of 35 days with 0.5% pulp density, initial pH of 2.5, using minus 0.16 mm size fraction at 32 degree C, as much as 54.45, 72.66, 97.13, and 31.30% Sn were extracted from synthetic stannite, kesterite, stannoidite and natural stannite, respectively. Varlamoffite, found in the dried, leached residues of the tin sulphides, provides evidence that bacterial action can be responsible for the genesis of supergene varlamoffite.

Effects of combined dopamine and nitroprusside therapy in patients with severe pump failure and hypotension complicating acute myocardial infarction

In severe pump failure with hypotension complicating acute myocardial infarction, dopamine has been useful in raising arterial pressure by increasing myocardial performance and augmenting peripheral resistance. Once adequate blood pressure are obtained, vasodilators may be used to reduce peripheral resistance and thus enhance pump performance. Accordingly, the hemodynamic effects of dopamine and nitroprusside administration were monitored in eight patients who developed hypotension following an acute myocardial infarction. With dopamine therapy alone, mean arterial pressure averaged 84 +/- 3.6 mm Hg and mean left ventricular filling pressure 32 +/-7.9 mm Hg. The addition of nitroprusside, at doses ranging from 0.5 to 1.6 micrograms/kg/min, resulted in a decrease in arterial pressure to 75 +/- 2.4 mm Hg (p less than 0.01) and in left ventricular filling pressure to 23 +/- 7.2 mm Hg (p less than 0.001). Cardiac index increased modestly from 1.81 +/- 0.61 to 2.01 +/- 0.60 liters/min/m2 (p less than 0.05), while systemic vascular resistance fell from 1,967 +/- 707 to 1,586 +/- 634 dynes-sec-cm-5 (p less than 0.01). Heart rate did not change significantly. Seven of eight patients died in the hospital within 4 days of admission. It appears that despite a beneficial hemodynamic response effected by combined dopamine-nitroprusside administration, the prognosis of this group of patients may not be favorably altered because of the extensive destruction of myocardium.

Leaching of a silicate and carbonate copper ore with heterotrophic fungi and bacteria, producing organic acids

Leaching of metals with carbon-heterotrophic microorganisms and organic acids as active agents has been performed with Timna copper ore containing 1.1% copper as carbonates and silicate and with some other metal oxides. Aspergillus niger surface cultures on a 14% sucrose fermentation medium yeilded 87.3% of total copper from 10% suspension within 2 weeks of leaching. On sulfite liquor as an industrial waste product A. niger solubilized 73.8% Cu within 4 weeks. In percolators with 14% sucrose medium up to 1780 ppm copper were found in solution. In leaching experiments with a sea water medium containing 7% sucrose only 684 ppm Cu were soluble. Leaching with lactobacilli containing whey yielded 83.4% of the total copper in 4 weeks.

[Bilateral fusion of the lesser multangulum (trapezoid) and the capitate in Turner's syndrome (author's transl)]

Fusion of the carpal bones, especially the lesser multangulum (trapezoid) and the capitate, are rare. Fusion of the lunate and triquetrum, however, are more common and are more frequent in negroes than in caucasians. The patient presented had Turner's syndrome, retarded bone age and shortening of the fourth metacarpals. Etiology, pathology, symptoms and possible relation to Turner's syndrome are discussed.

Amrinone: a new non-glycosidic, non-adrenergic cardiotonic agent effective in the treatment of intractable myocardial failure in man

Chronic congestive heart failure not controlled by conventional therapy was treated with intravenous amrinone, a new non-glycosidic, non-catecholamine cardiotonic agent. Eight patients with New York Heart Association functional class III-IV symptoms were hemodynamically monitored. At peak effect, cardiac index (CI) increased from 1.84 +/- 0.32 to 2.74 +/- 0.44 l/min/m2 (mean +/- SD) (p less than 0.001) and left ventricular filling pressure (LVFP) decreased from 25.8 +/- 6.2 to 19.5 +/- 6.8 mm Hg (p less than 0.05), while heart rate and mean aortic blood pressure did not change significantly. Mean endocardial circumferential fiber shortening (mean Vcf), determined by echocardiography, increased from 0.61 +/- 0.27 to 0.89 +/- 0.34 cir/sec (p less than 0.05). The duration of action after bolus infusion varied from 60--90 minutes. During continuous infusion of amrinone, sustained increases in CI and reductions in LVFP, similar to those at the time of peak effect after bolus administration, were maintained for 180 minutes. These marked cardiotonic effects of amrinone in patients already taking digitalis for severe heart failure occurred without side effects of arrhythmias or altered arterial pressures. The fact that the drug is orally active makes amrinone a v:ry promising inotropic agent for the treatment of chronic heart failure in man.