1. Free radicals mediate cerebral ischaemic injury associated with heatstroke. Magnolol, an active component of Magnolia officinalis, is 1000-fold more potent than alpha-tocopherol in inhibiting lipid peroxidation in rat mitochondria. The aim of the present study was to ascertain whether magnolol attenuated cerebral ischaemic injury and free radical formation associated with heatstroke. 2. Urethane-anaesthetized rats were exposed to heat stress (ambient temperature 42 degrees C) to induce heatstroke. Controlled rats were exposed to 24 degrees C. Mean arterial pressure, cerebral perfusion pressure and cerebral blood flow after the onset of heatstroke were all significantly lower than in control rats. However, colonic temperature, intracranial pressure, heart rate, cerebral free radicals, lipid peroxidation and the neuronal damage score were greater after the onset of heatstroke. 3. Magnolol (20 or 40 mg/kg, i.v.) significantly attenuated the heatstroke-induced hyperthermia, arterial hypotension, intracranial hypertension, cerebral ischaemia and neuronal damage and increased free radical formation and lipid peroxidation in the brain. The extracellular concentrations of ischaemic (e.g. glutamate and lactate/pyruvate ratio) and damage (e.g. glycerol) markers in the corpus striatum were increased after the onset of heatstroke. Magnolol significantly attenuated the increase in striatal ischaemia and damage markers associated with heatstroke. 4. Thus, it appears that magnolol has impressive effects against heatstroke reactions.

Animals↗

PubMedDate not supplied

Bacteremia in infants with Salmonella enterocolitis.

In order to determine the incidence of Salmonella bacteremia in children with Salmonella enterocolitis and to predict the risk factors of bacteremia, we conducted a prospective study on 264 infants and children with Salmonella enterocolitis from January 1, 1988 to December 31, 1989. They were admitted to the Pediatric Department of Mackay Memorial Hospital with the chief problem of diarrhea. The rectal swab cultures were all positive for nontyphoidal Salmonella. Blood cultures were done immediately when Salmonella enterocolitis was confirmed. Clinical features including age, clinical symptoms, laboratory data, and serogroup were all recorded and analyzed to predict the risk factors of bacteremia in Salmonella enterocolitis. Twenty patients had bacteremia. Among them, 4 had meningitis simultaneously. There was one death, resulting in a 5% mortality in the bacteremia group. The overall rate of bacteremia was 7.6%. For those less than 3 months of age, it was 11.5%. We were unable to find any relationship between the bacteremia and the risk factors such as age, body temperature, clinical symptoms, white blood cell counts and differential counts. Interestingly, it was noted that Salmonella serogroup D1, a highly virulent and invasive Salmonella serogroup, was more closely related to the occurrence of bacteremia. It accounted for 40% of all cases of bacteremia. In conclusion, this study showed that the incidence of bacteremia in cases of Salmonella enterocolitis was 7.6% and the only risk factor of bacteremia was a culture of Salmonella serogroup D1. Therefore, in cases of Salmonella serogroup D1 enterocolitis, antibiotics treatment may be considerable.

Adolescent↗