Synergistic action of trimethoprim and sulfamethoxazole for Nocardia asteroides: efficacious therapy in five patients

Eighteen isolates of Nocardia asteroides were tested for in vitro susceptibility to trimethoprim (TMP) and sulfamethoxazole (SMZ) alone and in various combinations using disc and paper strip diffusion tests. TMP-SMZ showed synergistic action for two-thirds of teh nocardia isolates tested. Five patients with Nocardia pneumonia were treated with TMP-SMZ and all were cured. Four of the patients' isolates were tested and all showed synergistic patterns of inhibition with the spaced disc and paper strip methods. The agar diffusion disc and synergy tests of TMP-SMZ appear to correlate with clinical usefulness when the Nocardia are susceptible with large zones of inhibition around the combination TMP-SMZ disc.     

Human immunodeficiency virus infection among members of the reserve components of the US Army: prevalence, incidence, and demographic characteristics. The Walter Reed Retrovirus Research Group

Since routine testing began, 677,463 members of the Reserve Components of the US Army have been tested for antibody to human immunodeficiency virus (HIV). Of these, 1063 were positive, for a crude prevalence of 1.57/1000 tested. Prevalence varied greatly among different groups as defined by sex, ethnicity, marital status, age, and geographic location. Multivariate analysis indicated that prevalence was higher among men, blacks, and unmarried men and peaked at ages 30-34. The crude incidence density was 0.20/1000 person-years, and multivariate analysis of incidence revealed patterns similar to those for prevalence. Comparison of prevalence and incidence data provides evidence that an increasing proportion of infection is occurring among women and in nonmetropolitan and small urban areas.     

Usefulness of right ventricular diastolic collapse in diagnosing cardiac tamponade and comparison to pulsus paradoxus

To compare the sensitivity, specificity and predictive value of right ventricular (RV) diastolic collapse and pulsus paradoxus as signs of cardiac tamponade, 21 consecutive patients with pericardial effusion and suspected cardiac tamponade underwent prospective hemodynamic and echocardiographic evaluation. Simultaneous hemodynamic and echocardiographic data were obtained in all patients before and after pericardiocentesis. Cardiac tamponade was considered present when there was diastolic equilibration of the intrapericardial, right atrial and pulmonary capillary wedge pressures and elevation of these pressures to more than 10 mm Hg. RV diastolic collapse was 93% sensitive and 100% specific in diagnosing cardiac tamponade, whereas pulsus paradoxus was only 79% sensitive and 40% specific. The positive and negative predictive values of RV diastolic collapse (100% and 83%) were considerably better than pulsus paradoxus (81% and 40%) and demonstrate that RV diastolic collapse is more sensitive, specific and predictive of cardiac tamponade than is pulsus paradoxus. Serial simultaneous hemodynamic and echocardiographic observations at multiple points during pericardiocentesis in a smaller subgroup (5 patients) also suggest that the hemodynamic effects of RV diastolic collapse in cardiac tamponade are mediated by an increase in intrapericardial pressure.     

Intracellular acidification enhances neutrophil phagocytosis in chronic haemodialysis patients: possible role of CD11b/CD18.

BACKGROUND: We have demonstrated that uraemic neutrophils that exhibit a low intracellular pH (pHi) display enhanced phagocytosis. However, the underlying cellular mechanism is unclear. METHODS: We used neutrophils from three groups of haemodialysis (HD) patients before dialysis (Groups A, B and C) and also from age- and sex-matched healthy individuals to determine pHi, phagocytosis and expression of CD11b, CD18, CD14 and toll-like receptors (TLR)-2 and TLR-4. The patients were categorized based on three consecutive monthly pre-dialysis plasma bicarbonate concentrations(P(HCO3)) and pH values; Groups A, B and C had a constant pre-dialysis P(HCO3) of /=26 mmol/L (mEq/L), respectively. We also studied the effects induced by the correction of metabolic acidosis and monoclonal antibodies (mAbs) against CD11b/CD18 on neutrophils in Group A. Furthermore, we investigated the effect of intracellular acidification on uraemic neutrophils ex vivo. RESULTS: We observed that the neutrophils in Group A exhibited significantly increased phagocytosis and expression of CD11b/CD18 compared with those in Groups B and C. Additionally, our ex vivo studies demonstrated that the mAbs against CD11b/CD18 partially blocked the enhancement of neutrophil phagocytosis in Group A. Moreover, the pHi of uraemic neutrophils is inversely correlated with phagocytosis and expression of CD11b/CD18. CONCLUSIONS: HD patients with a low P(HCO3) exhibited low neutrophil pHi that in turn increased the expression of CD11b/CD18 compared with neutrophils with a normal or high pHi. This increased expression of CD11b/CD18 on the uraemic neutrophils may contribute to the pHi-mediated phagocytosis.     

The effect of changes in afterload on Doppler echocardiographic indexes of left ventricular performance

To investigate the influence of changes in afterload on Doppler echocardiographic determination of peak aortic blood velocity, mean acceleration, and systolic velocity integral, eight dogs with their chests opened were studied in four inotropic states at varying levels of heart rate and mean aortic blood pressure. Data were collected in the control state, at two different levels of dobutamine administration (5 and 10 micrograms/kg/min intravenously), and after administration of propranolol (0.5 mg/kg intravenously). In each inotropic state, phenylephrine was infused intravenously to produce at least two successive steady state increases of 10 mm Hg or more in mean aortic blood pressure. Within a given animal, peak velocity emerged as the Doppler index most closely correlated with changes in Qmax, dQ/dt, and dP/dt (r = 0.94, 0.91, and 0.89, respectively). Mean acceleration also correlated closely with the invasive indexes (r = 0.87, 0.89, and 0.89). The effect of changes in mean aortic blood pressure on Doppler index measurements was not statistically significant in any of the inotropic states and did not affect the closeness of their correlation with the invasive indexes. We conclude that Doppler echocardiographic measurements of aortic blood peak velocity and mean acceleration remained as sensitive to changes in the inotropic state under conditions of varying increases in afterload as did the conventional invasive indexes tested.     

Measuring the requirements for nursing care in the acute head trauma patient

A measuring tool to assess the requirements for nursing care, define patient care goals, and document progress was developed in a 57-bed head trauma sub-acute rehabilitation center. The process of tool development and reliability testing is described.     

The effect of temperature on the growth and decay times of miniature end-plate currents in the mouse diaphragm

The temperature dependence of both the growth and the decay phases of miniature end-plate currents was investigated in the mouse diaphragm. The relationship between the log of the time constant of decay and reciprocal temperature was linear, that between the growth phase duration and temperature was not linear, the Q₁₀ being higher over the low end of the temperature range. The possible reasons for the non-uniform Q₁₀ of the growth time of the miniature end-plate current are discussed.