Evaluation of sampling sites for detection of upper respiratory tract carriage of Streptococcus pneumoniae and Haemophilus influenzae among healthy Filipino infants.

Two sampling techniques, nasal swabbing and oropharyngeal swabbing, for detection of the upper respiratory tract carriage of Streptococcus pneumoniae and Haemophilus influenzae were studied prospectively with 296 healthy Filipino infants at various ages: 6 to 8, 10 to 12, 14 to 17, 18 to 22, 32 to 39, and 46 to 65 weeks. In all age groups S. pneumoniae was isolated significantly more often (P < 0.0001) from the nasal site than from the oropharyngeal site. H. influenzae was found equally often at both sites.     

Expression of vascular endothelial growth factor and vascular endothelial growth factor receptor-2 (KDR/Flk-1) in ischemic skeletal muscle and its regeneration

Vascular endothelial growth factor (VEGF) is a hypoxia-inducible endothelial cell mitogen and survival factor. Its receptor VEGFR-2 (KDR/Flk-1) mediates these effects. We studied the expression of VEGF and VEGFR-2 in ischemic human and rabbit skeletal muscle by immunohistochemistry and in situ hybridization. Human samples were obtained from eight lower limb amputations because of acute or chronic critical ischemia. In chronically ischemic human skeletal muscle VEGF and VEGFR-2 expression was restricted to atrophic and regenerating skeletal myocytes, whereas in acutely ischemic limbs VEGF and VEGFR-2 were expressed diffusely in the affected muscle. Hypoxia-inducible factor-1alpha was associated with VEGF and VEGFR-2 expression both in acute and chronic ischemia but not in regeneration. Hindlimb ischemia was induced in 20 New Zealand White rabbits by excising the femoral artery. Magnetic resonance imaging and histological sections revealed extensive ischemic damage in the thigh and leg muscles of ischemic rabbit hindlimbs with VEGF expression similar to acute human lower limb ischemia. After 1 and 3 weeks of ischemia VEGF expression was restricted to regenerating myotubes and by 6 weeks regeneration and expression of VEGF was diminished. VEGFR-2 expression was co-localized with VEGF expression in regenerating myotubes. Macrophages and an increased number of capillaries were associated with areas of ischemic muscle expressing VEGF and VEGFR-2. In conclusion, two patterns of VEGF and VEGFR-2 expression in human and rabbit ischemic skeletal muscle are demonstrated. In acute skeletal muscle ischemia VEGF and VEGFR-2 are expressed diffusely in the affected muscle. In chronic skeletal muscle ischemia and in skeletal muscle recovering from ischemia VEGF and VEGFR-2 expression are restricted to atrophic and regenerating muscle cells suggesting the operation of an autocrine pathway that may promote survival and regeneration of myocytes.     

Temperature–Time Relationship in Collembolan Response to Chemical Exposure

Effects of temperature on chemical toxicity to a collembolan,Folsomia candida, in relation to time were studied in this experiment. Field soil was used as a test substrate. Collembolans were incubated at three different temperatures (+13, +16, and +19°C) and in two different dimethoate concentrations (1 and 3 mg/kg), clean soil serving as the control. Four destructive samplings were done at 2-week intervals. Dimethoate degradation was also analyzed. Dimethoate 1 mg/kg had a slight effect on both adult growth and reproduction, whereas 3 mg/kg was fatal toF. candidain the soil used. Toxic effects tended to last longer at low temperature than at high temperature, but the differences were not extensive. Temperature was negatively correlated with adult growth but positively correlated with reproduction. The dimethoate degradation rate was similar at all temperatures but differed with the concentration.     

Treatment of impaired perfusion in septic shock

Severe sepsis and septic shock are relatively common problems in intensive care. The mortality in septic shock is still high, and the main causes of death are multiple organ failure and refractory hypotension. Impaired tissue perfusion due to hypovolemia, disturbed vasoregulation and myocardial dysfunction contribute to the multiple organ dysfunction. Treatment of hemodynamics in septic shock consists of appropriate fluid therapy guided by invasive monitoring combined with vasoactive drugs aiming to correct hypotension and inappropriately low cardiac output. The drug of choice for low vascular resistance is norepinephrine, while insufficient myocardial contractility is commonly treated with dobutamine. The use of norepinephrine seems to be associated with better prognosis as compared to results from the use of dopamine or epinephrine. In septic shock, vasopressin levels are low, and therefore, vasopressin has been advocated as a vasopressor. Its effectiveness and safety have not yet been documented, and so far it is regarded as an experimental treatment. Recent data support the use of corticosteroid, at least in some of the patients with septic shock. Also, activated protein C, a drug with anti-inflammatory and antithrombotic properties, decreases mortality in patients with septic shock.