Biomedical subjects

Y J Hung

Publications and source records attributed to Y J Hung.

8 recordsLinked to original sources

PubMed2007

Surrogate estimates of insulin sensitivity in subjects with hypertension.

The purpose of the study is to compare surrogate estimates of insulin sensitivity with a directly measured insulin sensitivity index, steady-state plasma glucose (SSPG) from insulin suppression test (IST), in subjects with hypertension. Two hundred and twenty-eight hypertensive patients who received IST for SSPG were included for analysis. Estimates from fasting measurements alone, homeostasis model assessment for insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI)), and indices from fasting and/or 2 h samples (ISI(0,120) and ISI(TX)) were calculated. In addition to Pearson and partial correlations, variance-component models were used to test the relationship between surrogate estimates of insulin sensitivity and SSPG. A large proportion of variance owing to covariates in the variance-component models indicated the goodness of model fit, irrespective of the independence among variables. SSPG was positively correlated with logarithmic transformation (Log) (HOMA-IR) and negatively correlated with QUICKI, Log (ISI(0,120)) and ISI(TX) (all P<0.0001). Log (ISI(0,120)) seemed to have a better correlation with SSPG (r=-0.72) than other measures in partial correlation. The proportion of variance owing to all covariates of Log (ISI(0,120)) and ISI(TX) were larger than those of Log (HOMA-IR) and QUICKI in the variance-component models. After adjustments for demographic and obesity covariates, the proportion of variance explained by Log (ISI(0,120)) were largest among the surrogate measures in the variance-component models. Our results showed that ISI(0,120) and ISI(TX) correlated better with SSPG than those used fasting measures alone (HOMA-IR and QUICKI). Log (ISI(0,120)) currently showing the strongest association with SSPG than other estimates is adaptable for use in large studies of hypertension.

Adult↗

PubMed2003

The effect of surgical stress on insulin sensitivity, glucose effectiveness and acute insulin response to glucose load.

Hyperglycemia after stress is a very common clinical phenomenon. It is generally hypothesized that the underlying cause is a neuroendocrine-mediated deterioration in glucose metabolism. However, the detailed roles of insulin sensitivity, glucose effectiveness and acute insulin response to glucose load in response to stress have not been well established. Hernioplasty was used as a minor stress model for studying stress-induced hyperglycemia. Eleven healthy young men were enrolled voluntarily in this study. Their mean age was 22.0 +/- 0.9 yr and BMI 23.3 +/- 0.6 kg/m2. Frequently sampled i.v. glucose tolerance tests were performed one day before and one day after the surgery. Insulin sensitivity (SI), glucose effectiveness (EG) and area under acute insulin response (AIR) were calculated from "minimal model" algorithms. We also measured fasting concentrations of human GH, ACTH and F on the days of the test. Compared to the pre-operation data, levels of ACTH and F did not change significantly after the surgery. Only GH levels were marginally significant. On the other hand, the SI (0.75 +/- 0.1, 0.52 +/- 0.9 x 10(-5) min(-1)/pmol, p = 0.04), EG (0.023 +/- 0.03, 0.016 +/- 0.003 min(-1), p = 0.01) and AIR (6738.5 +/- 1111.6, 5130.0 +/- 1047.2 pmol, p = 0.005) were all significantly decreased after surgery. The percentages of decrease were 16.3 +/- 15.5, 32.1 +/- 10.3 and 17.8 +/- 10.3%, respectively. Finally, only the changes of EG positively correlate with the changes of ACTH before and after surgery. No significant changes were noted among other stress hormones and the changes of SI, EG and AIR. In conclusion, hernioplasty results in reduced SI, EG and AIR. Among them, although not statistically significant, the EG showed the most distinct decrease after the surgery, which has not been found in previous literature.

Adolescent↗

PubMed2001

The glycine allele of a glycine/arginine polymorphism in the beta2-adrenergic receptor gene is associated with essential hypertension in a population of Chinese origin.

BACKGROUND: Several studies implicate polymorphisms in the human beta-adrenergic receptor gene (ADRB2) in the susceptibility to hypertension. We sought to replicate these results in a population of Chinese origin primarily from Taiwan and the San Francisco Bay area. METHODS: We genotyped >800 hypertensive subjects and individuals with low-normal blood pressure that were derived largely from the same families as the hypertensive patients for three polymorphisms in the ADRB2 gene: a C/T transition at position 47 (C-47T) in the 5' leader cistron; another C/T transition that results in a glycine/ arginine substitution at codon 16 (Gly16Arg), and a G/C transversion that causes a glutamate/glutamine substitution at codon 27 (Glu27Gln). RESULTS: The Gly16Arg was significantly associated with hypertension (P < .03). Under a dominant model, for hypertension the relative risk for the Gly/Gly and Gly/Arg genotypes versus the Arg/Arg genotype was 1.35 (95% confidence limits [CL] 1.08, 1.70); for low-normal blood pressure the relative risk was 0.79 (95% CL 0.66, 0.94). This polymorphism explained approximately 1% of the variance in systolic and diastolic blood pressures in our study population. There was no evidence of association between the C-47T and Glu27Gln polymorphisms and hypertension in this population. CONCLUSIONS: The Glyl6 allele in the beta2-adrenergic receptor gene is a susceptibility allele for essential hypertension in a population of Chinese origin.

Arginine↗

PubMed2001

Alstrom syndrome in two siblings.

Alstrom syndrome is a very rare autosomal recessive inherited disorder. Only 50 cases have been reported since the syndrome was first described in 1959. This syndrome is characterized by obesity, impaired glucose tolerance with insulin resistance, retinal degeneration, neurosensory deafness, acanthosis nigricans, hepatic dysfunction, and some endocrine disorders. The index case of this report was a 12-year-old girl who became blind at the age of 6 years as the result of progressively impaired vision. At the age of 12, diabetes mellitus was diagnosed and acanthosis nigricans presented in the neck, axilla, and groin regions. Her 10-year-old brother had similar symptoms. Electroretinography and audiometry disclosed generalized pigmentary epithelial change, decreased to absent cone and rod responses, and moderate sensorineural hearing loss in both siblings. Biochemistry and oral glucose tolerance tests showed diabetes mellitus, dyslipidemia, and hepatic dysfunction in the index case. Elevations of insulin, C-peptide, and leptin concentrations were found in both siblings. Insulin resistance was also demonstrated in both siblings using the modified insulin suppression test with constant infusion of somatostatin and exogenous insulin.

Acanthosis Nigricans↗

PubMed1999

Effect of foot position on electromyographic activity of the vastus medialis oblique and vastus lateralis during lower-extremity weight-bearing activities.

STUDY DESIGN: Repeated measures analysis of the effects of foot wedges on quadriceps muscle function. OBJECTIVES: To investigate the relationship between foot position and 2 quadriceps muscle activation conditions: maximum voluntary isometric quadriceps muscle contractions with the knee extended and 1-leg short squats with a knee flexion range of motion of 0 degree to 50 degrees. BACKGROUND: Abnormal foot position has been suggested as an important factor which may lead to patellofemoral malalignment. No previous studies have examined the effects of foot position on activation of the vastus medialis oblique (VMO) and vastus lateralis (VL) muscles using weight-bearing exercises. METHODS AND MEASURES: Sixteen healthy volunteers performed the 2 exercises under 3 foot conditions: level surface, a 10 degrees medial wedge, and a 10 degrees lateral wedge. Subjects' electromyographic data for the VMO and VL were analyzed using ANOVA. RESULTS: The normalized VMO/VL ratio was significantly greater during the short squat than during the maximum voluntary isometric muscle contractions, but no significant differences were identified across the 3 foot positions. CONCLUSIONS: Clinicians should understand that the benefit of using a foot orthotic to correct a pronated or supinated foot might not result from a change in quadriceps muscle activation intensity but from other mechanical factors.

Adult↗

PubMed1999

Effects of lovastatin and gemfibrozil in subjects with high ratios of total cholesterol to high-density lipoprotein cholesterol.

Insulin resistance is associated with hypertriglyceridemia, low serum high-density lipoprotein cholesterol (HDL-C) concentrations and high serum total cholesterol (TC) to HDL-C ratios. Several reports have demonstrated that either lovastatin or gemfibrozil may favorably lower serum lipid concentrations. However, their effects on insulin sensitivity are unknown. The primary aim of this study was to compare the effects of lovastatin and gemfibrozil on insulin sensitivity and serum leptin concentrations in subjects with high TC/HDL-C ratios. We enrolled 25 nondiabetic patients, similar in terms of age and weight with TC/HDL-C ratios greater than 5. Thirteen subjects were treated with lovastatin 20 mg per day, and 12 received gemfibrozil 300 mg twice per day. Plasma lipids, glucose, and leptin were measured, and a 75-g oral glucose tolerance test (OGTT) and a modified insulin suppression test were performed before and after 3 months of treatment. The study showed the mean plasma TC, low-density lipoprotein cholesterol (LDL-C) concentrations, and TC/HDL-C ratio were significantly reduced in the lovastatin-treated group, but no obvious effects on plasma triglyceride (TG) and HDL-C were noted. In the gemfibrozil group, plasma TG and HDL-C were markedly lowered, but no significantly different effects in other plasma lipids were found. Gemfibrozil did not affect steady-state plasma glucose (SSPG) concentrations, whereas lovastatin significantly increased SSPG concentrations. Neither drug affected the serum leptin concentration during the OGTT. We conclude that lovastatin significantly lowers plasma TC and LDL-C ratio, and TC/HDL-C concentrations and adversely affects insulin sensitivity, while gemfibrozil markedly reduces plasma TG concentrations without altering insulin sensitivity in subjects with high TC/HDL-C ratios.

Adult↗

PubMed1995

Oral midazolam versus meperidine, atropine, and diazepam: a comparison of premedicants in pediatric outpatients.

An effective premedicant minimizes the emotional trauma children experience when facing surgery and may facilitate a smoother induction with fewer airway complications. In a randomized, double-blind study, the preoperative sedative effects and the postoperative recovery profiles of two oral pediatric premedicants were compared. Children (n = 102) were randomly assigned to receive 0.5 mg/kg midazolam or .2 mL/kg of a combination of meperidine 6.0 mg/mL, atropine 0.08 mg/mL, and diazepam 0.6 mg/mL 15-45 minutes before separation from parents. A five-point behavioral score was assigned at premedication, separation, and induction. Demographic data, preoperative preparation, analgesics, side effects, and recovery times were recorded. Scoring was continued at 15 and 30 minute intervals in the postanesthesia care unit (PACU). A majority of children in both groups achieved acceptable separation and induction scores; however, the midazolam subjects showed significantly better improvement in scores at both separation and induction (P < .01). In midazolam subjects, the age of the child did not influence induction scores; but in the meperidine/atropine/diazepam group, unacceptable scores were strongly associated with younger subjects (P < .01). Attendance at a children's preoperative preparation program did not affect scores. Midazolam subjects initially arrived in the PACU sleepier than pediatric anesthesia medicine subjects, but all other recovery scores were similar. There were no differences in analgesic requirements, side effects, or time to discharge between groups. We conclude that both premedicants are effective in most children, but that midazolam may offer more effective sedation in younger, distressed children.

Administration, Oral↗

PubMed1989

[Is synchronous hemorrhoidectomy with colonoscopy a worthwhile procedure?].

There were 201 patients receiving preoperative colonoscopy prior to hemorrhoidectomy in the meanwhile at MMH from July 1984 to June 1988. Other than rectal bleeding, they had colonic symptoms such as anemia, abdominal pain, familiar history of cancer and change of bowel habit etc. The study included 114 male and 87 female with ages ranging from 15 to 74 years (Median, 42 years). Three patients with colonic cancer and twenty-eight patients with neoplastic polyps were found by colonoscopic examination. Three cancer patients all received cancer surgery instead of hemorrhoidectomy as quickly as possible in a short time. One patient died for advanced stage and the other two patients got good results. The literatures were reviewed and discussed in accordance with the colonoscopic finding, operative time, hospital stay, post-operative morbidity and complication. There were not increase the postoperative morbidity in this series which compare with that of other series. The advantages of this procedure included: 1) Preventing suffer from twice colon preparations. 2) Preventing waiting period for Barium enema. 3) Preventing delay diagnosis of colorectal lesions especially colon cancer or precancer lesions of neoplastic polyps. 4) Performing examination and surgery at the same time-money-saving and time-saving. We thought synchronous hemorrhoidectomy with colonoscopy is a worthwhile clinical procedure.

Adolescent↗