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J X Li

Publications and source records attributed to J X Li.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Determination of inositol by reversed-phase high performance liquid chromatography].

A new method for determination of inositol by reversed-phase high performance liquid chromatography was studied. The method used a Shim-Pack CLC-C18 column, acetonitrile-water (10:90, V/V) as the mobile phase at a flow rate of 1.0 mL/min with detection wavelength at 196 nm. The RSD of the results was 0.8%. It is simple, rapid, accurate, and useful for quantitative determination of inositol product.

Chromatography, High Pressure Liquid↗
PubMed1999

Changes in membrane fluidity and lipid peroxidation of skeletal muscle mitochondria after exhausting exercise in rats.

We studied the effects of exhausting exercise and exercise training on skeletal muscle mitochondrial membrane fluidity and lipid peroxidation in rats. The first part of the study involved 60 untrained rats divided into six equal groups. Of the total number 10 rats were sedentary and acted as controls. The remaining 50 rats exercised to exhaustion and were sacrificed at 0-h, 24-h, 48-h, 72-h, and 96-h post-exercise. The second part of the study involved 40 rats which were divided into four equal groups. Of these 10 rats were sedentary and acted as controls. The remaining 30 rats underwent 8 weeks of exercise training. They were then subjected to a single period of exhausting exercise and were sacrificed at 0-h, 24-h and 48-h post-exercise. Membrane fluidity was measured using the fluorescence polarization method. Lipid peroxidation was estimated by determining the thiobarbituric acid-reactive substances (TBARS) in mitochondria. In the untrained rats, mitochondrial fluorescence polarization and TBARS contents were significantly increased post-exercise compared with the sedentary controls (P < 0.05). They did not return to near control levels until 96 h and 48 h, respectively. In the trained rats, fluorescence polarization was raised compared with the sedentary controls but this was significantly lower than those measured at the same times of the untrained group post-exercise (P < 0.05). Exhausting exercise decreased membrane fluidity and increased lipid peroxidation in rat skeletal muscle mitochondria. These effects were relieved to some extent by exercise training.

Animals↗
PubMed1999

Effect of verbascoside on decreasing concentration of oxygen free radicals and lipid peroxidation in skeletal muscle.

AIM: To detect the effects of verbascoside on decreasing the concentration of oxygen free radicals (OFR) and lipid peroxidation in skeletal muscle resulting from exhaustive exercise. METHODS: Electron spin resonance (ESR) technique and thiobarbituric acid reaction (TBAR) method were used to detect the concentration of OFR in intact gastrocnemius muscle and the contents of milondialdehyde (MDA) in muscle homogenate. RESULTS: Verbascoside decreased the concentration of OFR (P < 0.05) and the level of lipid peroxidation (P < 0.05) in muscle caused by exercise. CONCLUSION: Verbascoside has the effects of reducing oxidative stress in muscle caused by exhaustive exercise by decreasing the concentration of free radicals and the level of lipid peroxidation.

Animals↗
PubMed1999

Huperzine-A in capsules and tablets for treating patients with Alzheimer disease.

AIM: To compare the efficacy and safety between huperzine-A (Hup) in capsules and tablets for treating patients with Alzheimer disease (AD). METHODS: Using multicenter, prospective, double-blind, double-mimic, parallel, positive controlled and randomized methods, 60 patients meeting with the NINCDS-ARDRA criteria of AD were divided into 2 equal groups. Patients in the capsule group received 4 capsules of Hup (each contains 50 micrograms) and 4 tablets of placebo (lactose and starch inside); while the tablet group received 4 tablets of Hup (each contains 50 micrograms) and 4 capsules of placebo, p.o., twice a day for 60 d. All the patients were evaluated with a lot of related ranting scales, and physiological and laboratory examination. RESULTS: There were significant differences (P < 0.01) on all the psychological evaluations between 'before' and 'after' the 60-d trial of 2 groups, but there was no significant difference between 2 groups by group t test (P > 0.05). The changes of oxygen free radicals in 2 groups showed marked improvement. No severe side effect besides moderate to mild nausea was found in both groups. CONCLUSION: There is equal efficacy and safety between Hup in capsule and tablet for treating patients with AD, and Hup can reduce the pathological changes of the oxygen free radicals in the plasma and erythrocytes of patients with AD.

Aged↗
PubMed1998

Tribulusamide A and B, new hepatoprotective lignanamides from the fruits of Tribulus terrestris: indications of cytoprotective activity in murine hepatocyte culture.

Tribulusamides A (1) and B (2), new lignanamides embracing two cinnamic amide parts joined in a cis configuration, were isolated from the fruits of Tribulus terrestris, together with four known compounds, N-trans-feruloyltyramine (3), terrestriamide (4), N-trans-coumaroyltyramine (5), and beta-sitosterol. The structures were elucidated by 2D-NMR spectroscopy. Addition of compounds 1-5, especially 1 and 2, to primary cultured mouse hepatocytes significantly prevented cell death induced by D-galactosamine (D-GalN)/tumor necrosis factor alpha (TNF-alpha).

Animals↗
PubMed1998

Comparative study of seventeen Salvia plants: aldose reductase inhibitory activity of water and MeOH extracts and liquid chromatography-mass spectrometry (LC-MS) analysis of water extracts.

The dry root and rhizome of Salvia miltiorhiza (Lamiaceae) are used as a crude drug Danshen, while those of S. deserta (Xinjiang-Danshen) are mixed in Danshen at Xinjiang province when the former is in short supply. The water and MeOH extracts of S. deserta showed strong aldose reductase (AR) inhibitory activity, and their active constituents were determined to be polar compounds different from "tanshinones" of S. miltiorhiza, i.e., lithospermic acid B (1), salvianolic acid K (2), salviaflaside (3), and rosmarinic acid (4) (IC50, 2.63-3.91 microM). We also examined the AR inhibitory activity of water and MeOH extracts of seventeen Salvia plants, including ten species of Danshen resources (S. bowleyana, S. deserta, S. miltiorhiza, S. miltiorhiza var. miltiorhiza f. alba, S. paramiltiorhiza, S. paramiltiorhiza f. purpureo-rubra, S. przewalskii, S. przewalskii var. mandarinorum, S. sinica f. purpurea, S. trijuga), and their water extracts were also analyzed by liquid chromatography-mass spectrometry (LC-MS). The results indicated that there were four types with regard to the AR inhibitory activity and three types with regard to the amount of 1. Ten species used as Danshen resources showed good correlation between the AR inhibitory activity and the morphological classification. However, the intensities of their AR inhibitory activity varied, and they contained 1 in varying amounts. These facts suggested that the ten species were not the same, and thus their use as a Danshen resource should be based on their activity and/or active constituents.

Aldehyde Reductase↗
PubMed1997

Importance of epistasis as the genetic basis of heterosis in an elite rice hybrid.

The genetic basis of heterosis was investigated in an elite rice hybrid by using a molecular linkage map with 150 segregating loci covering the entire rice genome. Data for yield and three traits that were components of yield were collected over 2 years from replicated field trials of 250 F(2:3) families. Genotypic variations explained from about 50% to more than 80% of the total variation. Interactions between genotypes and years were small compared with the main effects. A total of 32 quantitative trait loci (QTLs) were detected for the four traits; 12 were observed in both years and the remaining 20 were detected in only one year. Overdominance was observed for most of the QTLs for yield and also for a few QTLs for the component traits. Correlations between marker heterozygosity and trait expression were low, indicating that the overall heterozygosity made little contribution to heterosis. Digenic interactions, including additive by additive, additive by dominance, and dominance by dominance, were frequent and widespread in this population. The interactions involved large numbers of marker loci, most of which individually were not detectable on single-locus basis; many interactions among loci were detected in both years. The results provide strong evidence that epistasis plays a major role as the genetic basis of heterosis.

Journal Article↗
PubMed1997

Effect of topical aclacinomycin on glaucoma filtration surgery in rabbits.

A prospective, randomized, double-masked and placebo-controlled study was performed to compare the effects of a single 5-minute intraoperative exposure to aclacinomycin (AMC) 0.4 mg/ml or 0.8 mg/ml with control eyes treated with saline solution on the success of glaucoma filtration surgery in 26 rabbits. Intraocular pressure (IOP), bleb survival, fistula patency and complications were evaluated. The results showed that IOP in the eyes treated with AMC was significantly lower than that in the control eyes from days 5-40 in the 0.4 mg/ml group and from days 5-20 in the 0.8 mg/ml group. The bleb survival lasted significantly longer in the two treated groups than in the control group and in the AMC 0.4 mg/ml group than in the AMC 0.8 mg/ml group. At 40 days, the rate of sclera fistula occlusion was 0% in the AMC 0.4 mg/ml eyes, 43.8% in the AMC 0.8 mg/ml eyes, and 100% in the control eyes. Significant complications, such as anterior chamber inflammation, hyphema, moderate and severe corneal haze, dense corneal neovascularization and mild cataract occurred only in the eyes treated with AMC 0.8 mg/ml. The results indicated that intraocular treatment with AMC at a dose of 0.4 mg/ml had a markedly beneficial effect on IOP, bleb appearance and fistula patency after experimental filtration surgery in rabbits.

Aclarubicin↗
PubMed1997

[Clinical observation on 112 cases with non-Hodgkin's lymphoma treated by Chinese herbs combined with chemotherapy].

OBJECTIVE: To seek for the effective therapeutical method in treating non-Hodgkin's lymphoma (NHL). METHODS: One hundred and sixty seven patients with non-Hodgkin's lymphoma were randomly divided into two groups, the treatment group, which consisted of 112 cases using Chinese herbs combined with chemotherapy and 55 cases of control group were treated by chemotherapy only. RESULTS: The effective rate (CR + PR) in the combined group was 91.96% and survival rates of 1-, 3- and 5-year were 85.7%, 54.5% and 29.5% respectively, and median survival time was 554 days. In control group the effective rate was 72.73% and 1-, 3- and 5-year survival rates were 76.4%, 38.2% and 18.2% respectively, and the median survival time was 465 days. The difference of effective rates or 3-year survival rates between two groups was significant (P < 0.05). In the combined group the activity of NK cell, OKT3, OKT4 and ratio of OKT4/OKT8 were obviously raised after treatment (P < 0.01). And the level of platelet adhesion rate and the blood viscosity markedly decreased (P < 0.01), but in the control group the values of these indexes did not distinctly change. CONCLUSION: Chinese herbs could enhance the immunologic function and improve the viscosity of blood of the patients with NHL. The side effect in the combination therapy group was less and milder than that in the chemotherapy group. These showed that Chinese herbs combined with chemotherapy was a safe and effective method for treating NHL and deserve to be recommended.

Adolescent↗
PubMed1996

Cell proliferation and esophageal carcinogenesis in the zinc-deficient rat.

Target cell proliferation was investigated throughout the development of esophageal cancer induced by N-nitroso-methylbenzylamine (NMBA) in weanling rats maintained on zinc-deficient or sufficient diets. Deficient rats were fed ad libitum, while zinc-sufficient rats were either pair-fed to the deficient animals or fed ad libitum. After 5 weeks, half of the animals in each dietary group were given six intragastric doses of NMBA (2 mg/kg; twice weekly). The remaining rats were untreated by carcinogen. At weeks 1, 2, 3, 4, 5, 7, 9 and 11 post first dose, esophageal cell proliferation was assessed in rats from each group by in vivo bromodeoxyuridine (BrDU) labeling followed by immunohistochemical detection of cells in S-phase. At 11 weeks, the tumor incidence was 100, 23 and 6%, respectively, in the zinc-deficient, zinc-sufficient, ad libitum and pair-fed groups. In vivo BrDU labeling revealed that in the NMBA-untreated groups, the labeling index (LI), the number of labeled cells, and the total number of cells per cross section of entire esophagi were significantly increased by zinc deficiency at all time points; LI was lowest in zinc-sufficient, pair-fed rats. During NMBA treatment (weeks 6, 7 and 8), increased cell proliferation occurred in both groups of zinc-sufficient esophagi but only during week 6 in the deficient ones. In the weeks following the cessation of NMBA treatment, zinc-deficient esophagi showed significantly increased LI and greater number of labeled cells than the carcinogen treated, zinc-sufficient pair-fed or ad libitum fed groups. On the other hand, NMBA-treated zinc-sufficient pair-fed rats showed lower LI and smaller number of labeled cells than their zinc-sufficient ad libitum counterparts. Most importantly, esophageal papillomas were found in two zinc-deficient animals that had received no NMBA treatment, after 10-11 weeks of experimental diet. These data support a direct relationship between cell proliferation and tumor incidence, and also provide evidence that zinc deficiency and its associated cell proliferation could be carcinogenic.

Aging↗
PubMed1996

Endotoxin induces biphasic alterations in small intestinal myoelectric activity in fasted newborn piglets.

Previous studies have shown that i.v. endotoxin infusion causes gastrointestinal dysfunction and intestinal injury in piglets. The aim of this study was to investigate the effects of endotoxin on intestinal myoelectric activity in newborn swine and to correlate this with gastrointestinal and hemodynamic events. Three pairs of electrodes were implanted in the jejunal wall of piglets, and after recovery, intestinal myoelectric activity was continuously recorded in the conscious, fasted condition. The intestinal myoelectric activity on the control day showed regular, repeating migrating myoelectric complex (MMC) cycles, each of which was composed of the classic phases I, II, and III. Mean cycle duration was 67.0 +/- 18.7 min (+/- SD), and phase III comprised 9.1 +/- 2.2% of each cycle. On the next day, infusion of 30 micrograms/kg endotoxin caused an initial, prolonged quiescent period and delayed the appearance of the first postendotoxin phase III complex. After the quiescent period, there was a period of irregular spiking activity followed by several shortened MMC cycles (47.9 +/- 22.7 min, p < 0.01 versus control) with a prolongation of the percentage of time spent in phase III (15.4 +/- 11.3%, p < 0.01). Endotoxin thus produced biphasic alterations in intestinal myoelectric activity characterized by an initial quiescence followed by increased gastrointestinal smooth muscle activity. Animals developed diarrhea, hypotension, and tachycardia about 1 h after endotoxin infusion in temporal association with increased spiking activity and MMC cycling. These studies are the first to show this biphasic response to endotoxin.

Activity Cycles↗
PubMed1995

Delayed thromboxane or tumor necrosis factor-alpha, but not leukotriene inhibition, attenuates prolonged pulmonary hypertension in endotoxemia.

The early phase of endotoxin-induced acute hemodynamic disturbances and hypoxemia is mediated by various factors, including eicosanoids and tumor necrosis factor-alpha (TNF alpha). Thromboxane A2 is the major mediator of the early pulmonary hypertension associated with endotoxemia, but the mechanisms underlying the prolonged hemodynamic disturbances observed in ongoing endotoxemia are not well understood. The authors used a chronically instrumental young piglet model to determine the roles of several eicosanoids and of TNF alpha in the prolonged endotoxin-induced pulmonary hypertension and other cardiovascular derangements. Animals were given 40 micrograms/kg endotoxin intravenously per hour for 30 minutes, followed by 20 micrograms/kg per hour. In all animals, persistent pulmonary hypertension, lowered cardiac output, any hypoxemia developed during endotoxin infusion. After 3 hours of endotoxin infusion, randomly ordered infusions of 1 mg/kg dazmegrel (a thromboxane A2 synthesis inhibitor), 5mg/kg nordihydroguaiaretic acid (a 5-lipoxygenase inhibitor), and 20 mg/kg pentoxifylline (A TNF alpha inhibitor) were given intravenously at 30-to-60-minute intervals. Dazmegrel and pentoxifylline lowered pulmonary arterial pressure and resistance and raised arterial oxygen tension. Cardiac output increased significantly after pentoxifylline. These hemodynamic effects persisted for 30-60 minutes, despite continued endotoxin infusion. The elevated plasma concentrations of thromboxane B2 and TNF alpha returned toward preendotoxin baseline values after dazmegrel and pentoxifylline treatment, respectively. No beneficial effects were noted after administration of nordihydroguaiaretic acid. Based on these results, both thromboxane A2 and TNF alpha, but not 5-lipoxygenase products, play active roles in prolonged endotoxin-induced pulmonary hypertension and hypoxemia in young piglets. Combined thromboxane A2 and TNF alpha blockade may be clinically useful in treatment of advanced sepsis in neonates.

6-Ketoprostaglandin F1 alpha↗
PubMed1994

Effects of cholinergic blockade on hemodynamic disturbances and intestinal lesions in endotoxic shock in newborn piglets.

The parasympathetic nervous system actively participates in the regulation of pathophysiologic responses in circulatory shock. To determine the effects of cholinergic blockade in endotoxic shock in newborn piglets, 16 chronically instrumented newborn piglets were infused with 10 mg/kg of endotoxin over 10 min. Eight animals were injected intravenously with 10 mg/kg of anisodamine, an anticholinergic drug, 10 min before endotoxin and then with escalating doses of 2, 5, 10, and 20 mg/kg every 10 min, beginning 60 min after endotoxin. The other eight animals were given saline as a control. Endotoxin infusion caused elevations in mean pulmonary artery pressure and vascular resistance index and an initial increase in systemic artery pressure followed by hypotension. Heart rate was stable for 45 min and then increased. Cardiac index fell from a baseline of 173 +/- 20 (mean +/- S.E.) to 136 +/- 23 mL.min-1.kg-1 60 min after endotoxin. Pretreatment with anisodamine increased heart rate from 163 +/- 15 to 289 +/- 10 beats.min-1 and cardiac index from 195 +/- 15 to 238 +/- 14 mL.min-1.kg-1 before endotoxin infusion. These variables remained at higher levels than in the control group until 60 min after endotoxin infusion; thereafter, the two groups were similar. The changes in pulmonary and systemic artery pressures were not significantly altered by anisodamine. After 60 min, additional doses of anisodamine caused no significant hemodynamic responses, and the differences between the two groups were not significant. Arterial plasma thromboxane B2 levels rose immediately and tumor necrosis factor-alpha levels increased 60 min after endotoxin infusion; no significant differences were noted between groups at any time.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1994

[The clinicopathologic study of histiocytic necrotizing lymphadenitis and the differentiated diagnosis with malignant lymphoma--report of 31 cases].

Histiocytic necrotizing lymphadenitis (HNL) is a kind of rare benign disease, predilection to involve the neck of young women, causing enlargement of the lymph nodes and usually accompanying by fever and other constitutional symptoms, and a unique clinicopathologic course are characteristic of this disease. Because its histomorphology has a given spectrum changing, it may lead to misdiagnosis for someone who is unfamiliar with it. According to the document records, misdiagnostis of HNL could be up to 30%-40%, especially in its early proliferative stage. In this 31 cases analysis, the authors systematically summarize the clinicopathologic characteristics of this lesion, and focus to elucidate the different features between HNL and lymphoma. Although presently it is thought that the disease is self-limited, there are two cases with clinical manifestations of systemic lupus erythematosus in our series. Possibly, the two diseases may have some intrinsic relationships. Long term follow-up of its final outcome in these patients is necessary to clarify whether or not HNL is a self-limiting or progressive disease.

Adolescent↗
PubMed1994

[A clinicopathological study of 8 cases of Castleman's disease].

Castleman's disease (CD) is a chronic lymphoproliferative disorder characterized by presence of giant lymphoid masses. The clinical features and histopathologic findings of 8 cases of CD diagnosed according to the criteria described by Frizzera were reported. 2 were male and 6 female; their age ranged from 26-66 years. Four patients with localized CD (three with hyaline vascular type and one with mixed type) had no systemic symptoms and had survived for a long time after surgery. Four patients with multicentric CD developed anemia, fever, elevated ESR, polyclonal immunoglobulinemia and manifestations of multisystem involvement. Steroids, chemotherapy, and radiotherapy had only resulted in partial remission in multicentric CD. The clinicopathologic differential diagnosis of CD from reactive lymph node hyperplasia in chronic infections, malignant lymphoma, connective tissue disease and angio-immunoblastic lymphadenopathy and the pathogenesis of CD were discussed.

Adult↗