Acute effects of using a mobile phone on CNS functions

Twenty volunteers participated in two experiments exploring the acute effects of using the mobile phone Motorola GSM 8700 on the functions of the CNS. When speaking (5 minutes reading a text from daily newspapers) the electromagnetic fields from the mobile apparatus did not affect the visual evoked potentials. Also a 6-min exposure did not reveal any effect of electromagnetic fields on the results in two tests (memory and attention) performed while speaking into the mobile. On the other hand the phone call itself strongly influenced the performance in a secondary task applying a test of switching attention which is a good model for driving a car. The response and decision speed were significantly worse. This is a proof that even a slight psychological stress involved in calling while driving can be a great risk.     

Problems associated with sterilization using ethylene oxide. Residues in treated materials

The paper deals with problems associated with reduction of undesirable effects of ethylene oxide in polymers in medical devices on the patient's health. The authors explain the need of careful elaboration and validation of the sterilization and aeration process incl assessment of ethylene oxide (EO) residues. The authors investigated the effect of the type of material and conditions of sterilization and aeration on the assessed EO concentration. For research of the behaviour of different polymers in the sterilization process model sterilizations of actual items of medical devices with a known composition proved more suitable than assessment in medical devices from medical institutions. The main conclusions of the investigation were a classification of polymers into those suitable and unsuitable for sterilization or resterilization, and attention was also drawn to poor reproducibility of results in old sterilizers, in particular those lacking effective aeration in aerators.     

Occupational risks for human reproduction: ELSPAC Study. European Longitudinal Study of Pregnancy and Childhood

Pregnant women living in Brno who were contacted for the first time at 18th week of their pregnancies during the period from February 1990 to January 1992 were involved into the ELSPAC group. Among others, the exposure to different occupational factors in the three periods was obtained by the self-reported questionnaire: 1. the last 9 months before pregnancy, 2. the first, and 3. second trimester periods. The women's health status during pregnancy, the history of delivery and the developmental and health status of newborns were described in details by obstetrics and pediatrics according to another internationally unified questionnaire. All data obtained from 3,897 pregnant women living in Brno were computered. Smoking women were significantly more often than non-smokers occupationally exposed to ergonomic stressors associated with the monotony work, and to chemical substances. In the whole group, the intrauterine growth retardation has been positively associated with shifting (OR 1.59, p < 0.05) and occupational exposure to permanent noise (OR 1.92, < 0.05). Newborns of such exposed women had in average lower parameters of head cimcumstances (p < 0.01). Non-physiologic, non-spontaneous deliveries have been more often observed among VDTs users (OR 1.20-1.28, p < 0.05). Women exposed to organic solvents during 2nd trimester of pregnancy delivered more often babies with some congenital malformations (OR 2.31, p < 0.05). On the other hand, the different occupational factors seemed to be protective for several markers of the women health status, as the prevalence of reproductive damages was significantly lower among exposed women than in the non-exposed group. After the standardization of the smoking habit, more significant associations have occurred in the group of smokers occupationally exposed to: shift work (low-birth-weight babies: OR 1.98, p < 0.05), chemicals (bleeding during pregnancy: OR 2.00, p < 0.05), sedentary work (placental abnormalities and congenital malformations: OR 1.59, p < 0.05). Non-smoking women using VDTs had more often babies with intrauterine growth retardation (OR 2.29, p < 0.05). Newborns with different malformations were more often born to non-smoking women occupationally exposed to chemicals (OR 2.33, p > 0.05).     

Birth weight of neonates as an indicator of morbidity and mortality in adult age and factors which influence it

In 28 neonates born by spontaneous delivery to healthy mothers with a normal course of gestation venous umbilical blood was examined to assess the immunoreactive insulin concentration. Moreover, the birth weight of the neonates was recorded, the weight increment of the mother during pregnancy and the body mass index at the end of gestation. By means of a questionnaire and the computer programme Progana the dietary intake of the mothers at the end of pregnancy was assessed and compared with recommended allowances. The assembled data were evaluated statistically by assessment of the correlation coefficient. The investigation revealed that the birth weight of the neonates in the group does not correlate with the immunoreactive insulin concentration in umbilical venous blood. Although the dietary intake of the mothers at the end of pregnancy is not ideal (fat and cholesterol intake predominates over carbohydrate and protein intake), it does not correlate with the birth weight of the neonates nor with the immunoreactive insulin concentration in umbilical venous blood. From these results the conclusion is drawn that neonates with a low birth weight do not have a higher plasma insulin concentration after delivery and that the mother's diet at the end of pregnancy does not influence the birth weight and insulin level in neonates.     

Influence of water and sodium diuresis and furosemide on urinary excretion of vitamin B(6), oxalic acid and vitamin C in chronic renal failure

Urinary excretion of vitamin B(6), oxalic acid and vitamin C was investigated in 15 healthy subjects during maximal water diuresis and in the group of 12 patients in polyuric stage of chronic renal failure without dialysis treatment receiving a diet containing high sodium chloride (15g/day). Urinary excretions of the same parameters were investigated in another group of 15 patients in polyuric stage of chronic renal failure without dialysis treatment after i.v. administration of 20 mg furosemide. Urinary excretion of vitamin B(6), oxalic acid and vitamin C significantly increased during maximal water diuresis while during high intake of sodium chloride the urinary excretions of these substances were not affected. The results suggest that urinary excretion of vitamin B(6), oxalic acid and vitamin C depends on the urinary excretion of water. Intravenous administration of 20 mg furosemide led to an increase of urinary excretion of vitamin B(6), oxalic acid and vitamin C in patients with chronic renal failure. The increased urinary excretion of vitamin B(6) and vitamin C is a new negative side effect of furosemide and increased urinary excretion of oxalic acid is a new positive side effect in patients with chronic renal failure.     

Neuroprotective effects of antidotes in soman-poisoned rats

1. The neuroprotective effects of antidotes (atropine, obidoxime/atropine mixture, HI-6/atropine mixture) on rats poisoned with soman at a sublethal dose (48 micrograms/kg i.m.; 60% of LD50 value) were studied. The neurotoxicity was monitored using a functional observational battery (FOB) and an automatic measurement of motor activity. The neurotoxicity of soman was monitored at 24 h and 7 d following soman poisoning. 2. The results indicate that atropine alone and the oxime HI-6 in combination with atropine seem to be effective antidotal treatment for the elimination of soman-induced neurotoxicity in the case of sublethal poisonings. 3. On the other hand, the combination of obidoxime with atropine appears to be practically ineffective in diminishing neurotoxic soman-induced symptoms. 4. Dealing with neuroprotective effects of antidotes, the oxime HI-6 in combination with atropine seems to be more suitable antidotal mixture than obidoxime in combination with atropine even in the case of sublethal poisoning with nerve agents.     

Inhibition of prostaglandin synthesis up-regulates cyclooxygenase-2 induced by lipopolysaccharide and peroxisomal proliferators

Primary cultures of fetal hepatocytes expressed cyclooxygenase-2 (COX-2) upon stimulation with bacterial lipopolysaccharide (LPS) or peroxisomal proliferators. This enzyme was active and a good correlation between the mRNA levels, the amount of protein, and the synthesis of prostaglandin E2 was observed. However, when cells were incubated in the presence of indomethacin or the COX-2-specific inhibitor NS398, the amount of COX-2 protein increased 5-fold after activation with LPS and 2-fold after treatment with clofibrate. This up-regulation of COX-2 was not observed at the mRNA level. The mechanism of protein accumulation might involve either a direct stabilization of the enzyme by the inhibitors or the absence of prostaglandins involved in the regulation of its turnover. Among the prostaglandins assayed, only 15-deoxy-Prostaglandin J2 exerted a statistically significant decrease in the COX-2 levels in cells stimulated with LPS or LPS plus NS398. The accumulation of COX-2 in the presence of inhibitors was also observed in peritoneal macrophages treated under identical conditions. These results indicate that COX-2 protein accumulates after enzyme inhibition, and because removal of the inhibitors restored the enzyme activity, suppression of treatment with reversible COX-2 inhibitors may cause a transient overproduction of prostaglandins.     

Comparison of adenosine and remifentanil infusions as adjuvants to desflurane anesthesia

BACKGROUND: Because adenosine has been alleged to produce both anesthetic and analgesic sparing effects, a randomized, double-blinded study was designed to compare the perioperative effects of adenosine and remifentanil when administered as intravenous adjuvants during general anesthesia for major gynecologic procedures. METHODS: Thirty-two women were assigned randomly to one of two drug treatment groups. After premedication with 0.04 mg/kg intravenous midazolam, anesthesia was induced with 2 micro/kg intravenous fentanyl, 1.5 mg/kg intravenous propofol, and 0.6 mg/kg intravenous rocuronium, and maintained with desflurane, 2%, and nitrous oxide, 65%, in oxygen. Before skin incision, an infusion of either remifentanil (0.02 microg x kg(-1) x min(-1)) or adenosine (25 microg x kg(-1) x min(-1)) was started and subsequently titrated to maintain systolic blood pressure, heart rate, or both within 10-15% of the preincision values. RESULTS: Adenosine and remifentanil infusions were effective anesthetic adjuvants during lower abdominal surgery. Use of adenosine (mean +/- SEM, 166+/-17 microg x kg(-1) x min(-1)) was associated with a significantly greater decrease in systolic blood pressure and higher heart rate values compared with remifentanil (mean +/- SEM, 0.2+/-0.03 microg kg(-1) x min(-1)). Total postoperative opioid analgesic use was 45% and 27% lower in the adenosine group at 0-2 h and 2-24 h after surgery, respectively. CONCLUSIONS: Adjunctive use of a variable-rate infusion of adenosine during desflurane-nitrous oxide anesthesia was associated with acceptable hemodynamic stability during the intraoperative period. Compared with remifentanil, intraoperative use of adenosine was associated with a decreased requirement for opioid analgesics during the first 24 h after operation.