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T Lim

Publications and source records attributed to T Lim.

26 records · Page 2Linked to original sources
PubMed1993

Pharmacodynamics of alfentanil as a supplement to propofol or nitrous oxide for lower abdominal surgery in female patients.

BACKGROUND: Although propofol and alfentanil are given in combination in clinical practice, the pharmacodynamic interaction between these drugs has not been described. METHODS: The pharmacodynamics of alfentanil when given as a supplement to propofol were studied in 10 ASA physical status 1 female patients (group P) undergoing lower abdominal surgery and compared to the pharmacodynamics of alfentanil when given as a supplement to nitrous oxide (group N, n = 10). Anesthesia was induced by either computer-controlled infusion of propofol and alfentanil at target concentrations of 3 micrograms/ml and 100 ng/ml (group P) or computer-controlled infusion of 400 ng/ml alfentanil as a supplement to nitrous oxide and oxygen (ratio 2:1; group N). The target concentration of alfentanil was varied to patient responses, and the nitrous oxide and propofol concentrations were maintained constant. A sigmoid Emax model was fitted to response/no response data versus plasma alfentanil concentrations at intubation, skin incision, and the opening of the peritoneum in both groups and for the intraabdominal part of surgery in the individual patients. In addition, the speed of recovery in both groups was determined by a deletion-of-p's test. RESULTS: The EC50 (the concentration at which, with a 50% probability, the patients did not respond to the surgical stimuli) of alfentanil during propofol anesthesia was 92 ng/ml for intubation, 55 ng/ml for skin incision, 84 ng/ml for the opening of the peritoneum, and 66 +/- 38 ng/ml (mean +/- SD) for the intraabdominal part of surgery. The corresponding values during nitrous oxide anesthesia were significantly higher: 429 ng/ml for intubation, 101 ng/ml for skin incision, and 206 +/- 65 ng/ml for the intraabdominal part of surgery (P < 0.001). The speed of recovery was similar in both groups. CONCLUSIONS: The alfentanil requirements in ASA physical status 1 female patients undergoing lower abdominal surgery are less when given as a supplement to propofol (4 micrograms/ml) compared to 66% N2O.

Abdomen↗
PubMed1992

Plasma 25-hydroxyvitamin D3 and its relation to physical activity and other heart disease risk factors in the general population.

The relation between plasma levels of 25-hydroxyvitamin D3, the main metabolite of sun-induced vitamin D, and major coronary heart disease risk factors was examined in 295 men, aged 35 to 64 years, who were randomly sampled from the general population. Men who did regular vigorous leisure-time activity had a mean plasma 25-hydroxyvitamin D3 level that was 4.8 nmol/L (95% confidence limits: 0.1, 9.5) higher than that in inactive men, with the increase greatest in the winter months. Plasma 25-hydroxyvitamin D3 was positively associated with weekly hours of sun exposure (r = 0.27, P < 0.01), and showed a weak inverse association with age (r = -0.12, P < 0.05) and diastolic blood pressure (r = -0.15, P < 0.05), although this latter finding was no longer significant when allowance was made for the effects of age and season on vitamin D levels. In contrast, plasma 25-hydroxyvitamin D3 had no relation with either serum total or high-density-lipoprotein cholesterol levels, body mass index, or cigarette smoking. We hypothesize that vigorous leisure-time activity may protect against coronary heart disease, in part, by increasing body levels of vitamin D.

Adult↗
PubMed1990

Myocardial infarction is inversely associated with plasma 25-hydroxyvitamin D3 levels: a community-based study.

The relation between the plasma level of 25-hydroxyvitamin D3, the main metabolite of sun-induced vitamin D, and myocardial infarction (MI) was investigated in a community-based case-control study. Some 179 MI patients presenting to hospital within 12 hours of the onset of symptoms were individually matched with controls by age, sex and date of blood collection. MI patients had significantly lower mean 25-hydroxyvitamin D3 levels than controls (32.0 versus 35.5 nmol/L; p = 0.017), with the case-control differences being greatest in winter and spring. The relative risk of MI for subjects with 25-hydroxyvitamin D3 levels equal to or above the median was 0.43 (95% confidence limits = 0.27, 0.69) compared to subjects below the median. The decrease in MI risk associated with raised vitamin D3 levels was observed in all seasons. These results provide support for the hypothesis that increased exposure to sunlight is protective against coronary heart disease.

Adult↗
PubMed1987

Cephalhaematoma: a 10-year review.

The incidence of cephalhaematoma at the Mercy Maternity Hospital over a 10-year period was 2.5%; of the 1,030 infants 68.4% were born to primiparas, 65.6% were males, the majority (91.1%) were between 37 and 42 weeks' gestation and 3,000 and 4,000 g birth-weight (71.6%). Forceps delivery and vacuum extraction were associated with increased incidences of cephalhaematoma (5.1% and 22.9% respectively), and the incidence was slightly increased (3.8%) when a scalp electrode had been applied. Hyperbilirubinaemia was more prevalent (12.9%) in infants with a cephalhaematoma as was exchange transfusion (0.8%) and the need for phototherapy (4.9%).

Birth Injuries↗
PubMedDate not supplied

Detection of toxic chemicals with high sensitivity by measuring the quantity of induced P450 mRNAs based on surface plasmon resonance.

In this study we describe a novel sensor system to detect toxic chemicals based on measurement of the quantity of Saccharomyces cerevisiae P450 mRNAs induced by them. Detection was conducted using a flow-injection-type sensor system based on surface plasmon resonance (SPR). The DNA and peptide nucleic acid (PNA) probes containing a complementary sequence to a part of P450 mRNA were immobilized on the sensor chip and the P450 mRNAs hybridized to the probes were quantified. We succeeded in detecting 10 ng/L (10 ppt) of atrazine using both DNA and PNA probes. Using this sensor system, we were able to detect bisphenol A in addition to atrazine. Furthermore, we achieved higher sensitivity by amplifying the target P450 mRNA based on nucleic acid sequence-based amplification (NASBA). This method allows for sensitive, rapid, and easy detection of some toxic chemicals.

Atrazine↗
PubMedDate not supplied

Inhibitory effect of Asparagus cochinchinensis on tumor necrosis factor-alpha secretion from astrocytes.

We investigated whether an aqueous extract of Asparagus cochinchinensis Merrill (Liliaceae) roots (ACAE) inhibits secretion of tumor necrosis factor-alpha (TNF-alpha) from primary cultures of mouse astrocytes. ACAE dose-dependently inhibited the TNF-alpha secretion by astrocytes stimulated with substance P (SP) and lipopolysaccharide (LPS). IL-1 has been shown to elevate TNF-alpha secretion from LPS-stimulated astrocytes while having no effect on astrocytes in the absence of LPS. We therefore investigated whether IL-1 mediated inhibition of TNF-alpha secretion from astrocytes by ACAE. Treatment of ACAE to astrocytes stimulated with both LPS and SP decreased IL-1 secretion. Moreover, incubation of astrocytes with IL-1 antibody abolished the synergistic cooperative effect of LPS and SP. These results suggest that ACAE may inhibit TNF-alpha secretion by inhibiting IL-1 secretion and that ACAE has a antiinflammatory activity in the central nervous system.

Animals↗