Biomedical subjects

Jue Li

Publications and source records attributed to Jue Li.

12 recordsLinked to original sources

PubMed2005

[Research of the relationship between smoking and peripheral arterial disease].

OBJECTIVE: To investigate the relationship between smoking and peripheral arterial disease (PAD) by investigate the smoking status and measuring the (ABI). METHODS: A questionnaire survey was conducted among 3379 male patients hospitalized in the departments of cardiovascular internal medicine, nephrology, and endocrinology, aged 40-98, 2253 smokers and 1126 non-smokers, to understand their life styles, anamnesis, and smoking history. All patients underwent measurement of systolic blood pressures of the upper arm and ankle so as to calculate the ankle-brachial index (ABI). Measurement. An ABI less than or equal to 0.9 was considered to be indicative of significant PAD. RESULTS: The ABI levels in the smoker group were significantly lower than those in the non-smoker group (P < 0.05). The prevalence of PAD was 24.94% in the smoker group, and 20.60% in the non-smoker group. The age-adjusted OR of the smokers was 1.480 (95% CI: 1.237-1.770), with a significant dosage-effect relationship between smoking and PAD. CONCLUSION: Smoking is a significant risk factor of PAD. The prevalence of PAD was increased with the dosage of smoking.

Adult↗

PubMed2005

Imaging the heart: computer 3-dimensional anatomic models of the heart.

Since the 1960s, models of the action potential in various cardiac cell types have been developed, and since the 1990s, 3-dimensional anatomic (or geometric) models of various cardiac structures have been developed. We are approaching the time when, for one species, we should have a complete set of action potential and anatomic models for the various cardiac tissues and then we will have realized the aim of constructing a "virtual heart" with accurate anatomy and electrophysiology. However, already the two types of model are beginning to be used in tandem to reconstruct the activation sequence of the heart both during sinus rhythm and arrhythmias.

Action Potentials↗

PubMed2004

Low-fat milk promotes the development of 7,12-dimethylbenz(A)anthracene (DMBA)-induced mammary tumors in rats.

Commercial cow milk contains considerable amounts of estrogens. Our study assessed the effect of commercial low-fat milk on the development of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumors in rats. Eighty 6-week-old female Sprague-Dawley rats received a single oral dose of 5 mg DMBA. Twenty-four hours later, the animals were divided into 4 groups of 20 animals each and given 1 of 4 test solutions for 20 weeks as their drinking liquid: low-fat (1%) milk (M), artificial milk (A), estrone sulfate solution (0.1 microg/ml, E), or tap water (W). The artificial milk was formulated to supply essentially the same calories as the milk. The low-fat milk contained 378 pg/ml estrone sulfate. Tumor incidence, the cumulative number of tumors and the sum of tumor diameters were higher in the M and E groups than in the A or W groups. Overall, the development of mammary tumors was in the order: M = E > A = W. Whereas the plasma 17beta-estradiol concentration in the M group was the 2nd highest after the E group, the plasma level of insulin-like growth factor (IGF-I) was significantly higher in the M group than in the other 3 groups. In conclusion, commercially available low-fat milk promotes the development of DMBA-induced mammary tumors in rats. The degree of the promotion is almost comparable to that of 0.1 microg/ml estrone sulfate. The high estrogen content in the milk may be responsible for the promotional effects, acting in concert with other hormones such as IGF-I.

9,10-Dimethyl-1,2-benzanthracene↗

PubMed2004

Structure-function relationship in the AV junction.

In the normal heart, the atrioventricular node (AVN) is part of the sole pathway between the atria and ventricles. Under normal physiological conditions, the AVN controls appropriate frequency-dependent delay of contractions. The AVN also plays an important role in pathology: it protects ventricles during atrial tachyarrhythmia, and during sinoatrial node failure an AV junctional pacemaker can drive the heart. Finally, the AV junction provides an anatomical substrate for reentry. Using fluorescent imaging with voltage-sensitive dyes and immunohistochemistry, we have investigated the structure-function relationship of the AV junction during normal conduction, reentry, and junctional rhythm. We identified molecular and structural heterogeneity that provides a substrate for the dual-pathway AVN conduction. We observed heterogeneity of expression of three isoforms of connexins: Cx43, Cx45, and Cx40. We identified the site of origin of junctional rhythm at the posterior extension of the AV node in 79% (n = 14) of the studied hearts. This structure was similar to the compact AV node as determined by morphologic and molecular investigations. In particular, both the posterior extension and the compact node express the pacemaking channel HCN4 (responsible for the I(F) current) and neurofilament 160. In the rabbit heart, AV junction conduction, reentrant arrhythmia, and spontaneous rhythm are governed by heterogeneity of expression of several isoforms of gap junctions and ion channels. Uniform neurofilament expression suggests that AV nodal posterior extensions are an integral part of the cardiac pacemaking and conduction system. On the other hand, differential expression of Cx isoforms in this region provides an explanation of longitudinal dissociation, dual-pathway electrophysiology, and AV nodal reentrant arrhythmogenesis.

Animals↗

PubMed2003

The effects of nocturnal life on endocrine circadian patterns in healthy adults.

We observed the 24-hour patterns of endocrine in medical students who lived either a diurnal life or nocturnal life. Nocturnal life was designed by skipping their breakfast but consuming much (>50% of their daily food intake) in the evening and at night with the sleep from 0130 h to 0830 h the next morning. After 3 weeks in the experimental life, the 24-hour plasma concentrations of melatonin, leptin, glucose and insulin were measured every three hours. Both plasma melatonin and leptin showed peaks at 0300 h in the diurnal lifestyle group, and the night peaks decreased in the nocturnal lifestyle group. The changes in the patterns of melatonin and leptin were highly consistent with that of night-eating syndrome (NES). Plasma glucose increased after all meals in both groups. Its concentration maintained a high level in the nocturnal lifestyle group between midnight and early morning while insulin secretion decreased markedly during this period. Furthermore, the strong association between glucose and insulin in the diurnal lifestyle group after meals was damaged in the nocturnal lifestyle group. It was suggested that nocturnal life leads to the impairment of insulin response to glucose. Taking these results together, nocturnal life is likely to be one of the risk factors to health of modern people, including NES, obesity and diabetes.

Adult↗

PubMed2003

Long-term effects of high dietary fiber intake on glucose tolerance and lipid metabolism in GK rats: comparison among barley, rice, and cornstarch.

Whether the intake of high dietary fiber may improve glycemic control in individuals with type 2 diabetes has been controversial. This study was conducted to observe the long-term effects of dietary fiber intake on glucose tolerance and lipid metabolism in rats. Thirty male type 2 diabetic model GK rats were divided randomly into 3 groups. Each group was fed either a barley (high-dietary fiber) diet, rice (low-dietary fiber) diet, or cornstarch (very-low-dietary fiber) diet. The rats were pair-fed for 9 months. The intake of the barley diet significantly improved the area under the plasma glucose concentration time curves, lowered the fasting plasma glucose and glycosylated hemoglobin levels, and decreased plasma total cholesterol (T Chol), triglycerides (TG), and free fatty acid (FFA) levels. This study demonstrated that long-term intake of barley has beneficial effects on glucose tolerance and lipid metabolism and suggests the intake of unrefined cereal foods should increase as a diet therapy for type 2 diabetes.

Animals↗

PubMed2003

[Effects of dietary fiber on the glucose tolerance in spontaneously diabetic rats--comparison among barley, rice, and corn starch].

OBJECTIVES: In this study, the effects of a barley diet containing high dietary fiber on the onset and development of diabetes mellitus in spontaneously diabetic rats was investigated by comparing with a rice diet containing low dietary fiber and an alpha-corn starch diet containing very low dietary fiber. METHODS: 30 male Goto-Kakizaki (GK) strain rats (8 weeks of age) were randomly assigned to 3 groups; high barley (HB) group on a barley diet (dietary fiber intake, 1.79 g/day/rat), rice (R) group on a rice diet (dietary fiber intake, 0.46 g/day/rat), and alpha-corn starch (CS) group on an alpha-corn starch diet (dietary fiber intake, 0.24 g/day/rat). The carbohydrate (70%), fat (10%), and protein (20%) contents of these 3 diets were equal, and the rats were pair-fed each diet for 3 months. RESULTS: Feeding for 3 months showed that fasting plasma glucose level in the HB group was significantly lower than in the R and CS groups; the glucose tolerance in the HB group was markedly improved. Moreover, the plasma cholesterol and triglyceride levels in the HB group were significantly lower than those of the R and CS groups. CONCLUSIONS: Our findings demonstrated that barley enabled glycemic control and improved glucose tolerance compared with rice or alpha-corn starch.

Animals↗

PubMed2002

Isoflurane decreases AMPA-induced dark cell degeneration and edematous damage of Purkinje neurons in the rat cerebellar slices.

This study was designed to investigate whether isoflurane, a commonly used volatile anesthetic with neuroprotective property, reduces alpha-amino-3-hydroxy-5-methyl-4-isoxazol propionic acid (AMPA)-induced neurotoxicity in a concentration- and time (when isoflurane was applied in relation to the AMPA exposure)-dependent manner. Cerebellar slices from postnatal 10-14-day-old rats were exposed to 30 microM AMPA for 30 min followed by a 120-min AMPA-free recovery period at 37 degrees C. This protocol resulted in dark cell degeneration (DCD) in the majority of Purkinje neurons (60.8+/-6.9%). Fewer Purkinje neurons (31.6+/-5.2%) had edematous damage (ED) characters. Application of isoflurane (1, 2, or 3%) during both the AMPA exposure and recovery periods significantly increased the percentage of morphologically normal Purkinje neurons (neurons without DCD or ED changes) but the effects were apparently not dose-dependent. Isoflurane (3%) applied before, during or after the AMPA exposure period also significantly increased the percentage of morphologically normal Purkinje neurons. These isoflurane-induced increases in the percentage of morphologically normal Purkinje neurons were mainly due to fewer cells with DCD changes. Isoflurane decreased AMPA-induced ED significantly only when isoflurane (1 or 2%) was present during both the AMPA exposure and recovery periods. Isoflurane applied before, during or after the AMPA exposure period did not significantly affect the percentage of cells with ED changes. These results suggest that isoflurane time-dependently but not concentration-dependently reduce AMPA-induced neurotoxicity. These effects may be one mechanism for the isoflurane-induced neuroprotection demonstrated in previous studies.

Animals↗

PubMed2002

Troglitazone enhances the hepatotoxicity of acetaminophen by inducing CYP3A in rats.

Troglitazone (TRZ) is the first of a new group of oral antidiabetic drugs, the thiazolidinediones, and is proven to lower plasma glucose levels in patients with type 2 diabetes mellitus. However, the concern has been raised because of several reports, in which severe hepatic dysfunction leading to hepatic failure was demonstrated in a few patients receiving the drug. We studied the effects of TRZ on the hepatotoxicity of carbon tetrachloride (CCl(4)) and acetaminophen (APAP) in rats, both of which exert their toxic effects through bioactivation associated with cytochrome P450 3A (CYP3A) and 2E1 (CYP2E1). Male standard (Wistar/ST) and type 2 diabetic model (GK/Jal) rats were kept on a powdered chow diet containing 0, 100, 500 mg/kg/rat of TRZ. Three weeks later, the rats were either sacrificed for an in vitro metabolism study or challenged with 0.50 g/kg CCl(4) p.o. or 0.75 g/kg APAP i.p.TRZ at 100 and 500 mg/kg/rat increased the CYP3A level as well as the testosterone 6beta-hydroxylation activities in liver microsomes, but did not affect CYP2E1. TRZ also enhanced APAP hepatotoxicity, as evidenced by significantly increased levels of alanine aminotransferase, aspartate aminotransferase and alpha-glutathione S-transferase in the plasma of rats, and by significantly low hepatic glutathione concentration. Our study demonstrated that high doses of TRZ can enhance hepatotoxicity of APAP in Wistar/ST and GK/Jal by inducing hepatic CYP3A.

Acetaminophen↗

PubMed2002

Glucose intolerance induced by a high-fat/low-carbohydrate diet in rats effects of nonesterified fatty acids.

We examined the time course of effects of a high-fat/low-carbohydrate (HF/LC) diet on the impairment of glucose tolerance in rats, clarified whether insulin secretion and sensitivity were impaired by the HF/LC diet, and investigated the relationship between the increased nonesterified fatty acids (NEFA) after HF/LC diet feeding and insulin secretion and sensitivity. We found that glucose tolerance and the postglucose-loading insulin secretion were impaired after 3 and 7 d on the HF/LC diet. The glucose intolerance was accompanied by a rise in the fasting plasma NEFA level. When stimulated with 15 mmol/L of glucose, the insulin secretion was impaired in pancreatic islets from rats fed the HF/LC diet. Rats fed the HF/LC diet showed insulin resistance in vivo. The glucose-stimulated insulin secretion was inhibited in the islets following 24-h culture with palmitic acid. The 24-h infusion of palmitic acid decreased whole-body insulin sensitivity. In summary, at least 3 d on a HF/LC diet is needed to induce glucose intolerance in rats, and the impairment may be induced by decreased insulin secretion and sensitivity, which is related to the increase in the plasma NEFA level.

Animals↗

PubMedDate not supplied

Effects of fiber intake on the blood pressure, lipids, and heart rate in Goto Kakizaki rats.

OBJECTIVE: The prevalence of hypertension in individuals with diabetes mellitus is higher than that in individuals without diabetes mellitus. High fiber intake decreases blood glucose and lipids levels. This study investigated the effects of cereal fiber intake on systolic and diastolic blood pressures in a rat model of type 2 diabetes mellitus. METHODS: Thirty male Goto Kakizaki rats were randomly assigned to one of three groups. Each group was fed a barley diet, a white rice diet, or cornstarch diet. The rats were pair fed for 16 wk. Systolic and diastolic blood pressures were measured once every 4 wk by the photoelectric oscillometric tail-cuff method without anesthesia. RESULTS: The barley diet significantly decreased systolic blood pressure from week 12 and decreased the plasma levels of total cholesterol, triacylglycerol, and low-density lipoprotein cholesterol. There were significant positive correlations between plasma lipids levels and systolic blood pressure. CONCLUSIONS: High fiber intake has beneficial effects on systolic blood pressure and blood lipids levels and suggests that fiber intake should be increased in individuals who have diabetes mellitus to prevent complications.

Animals↗

PubMedDate not supplied

Effects of barley intake on glucose tolerance, lipid metabolism, and bowel function in women.

OBJECTIVE: The low consumption of grains that are rich sources of dietary fiber may be associated with the increasing prevalence of chronic diseases. This study was conducted to observe the effects of high barley (high-fiber diet) intake on glucose tolerance, lipid metabolism, and bowel function in healthy women. METHODS: Ten women volunteers (20.4 +/- 1.3 y, 19.2 +/- 2.0 kg/m2) signed informed consents and received a standard diet and a barley diet, with each diet for a period of 4 wk with a 1-mo interval (randomized cross-over design). Both diets contained the same amounts of carbohydrate, fat, and protein. RESULTS: The barley intake significantly lowered plasma total and low-density lipoprotein cholesterol concentrations and reduced plasma triacylglycerol concentration. Barley intake also increased stool volume. There was no significant difference in glucose tolerance between diet regimens. CONCLUSIONS: This study demonstrated that barley intake has beneficial effects on lipid metabolism and bowel function and suggests that the intake of a high-fiber food, i.e., barley, should be recommended to prevent chronic diseases.

Adult↗