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Biomedical subjects

X M Huang

Publications and source records attributed to X M Huang.

At least 37 records · Page 2Linked to original sources
PubMed1991

Reduction in brain serotonin markers by alpha-ethyltryptamine (Monase).

alpha-Ethyltryptamine (Monase) is both an inhibitor of monoamine oxidase and a monoamine releasing agent. To determine whether alpha-ethyltryptamine induces serotonergic deficits similar to that of other monoamine releasing agents such as 3,4-methyl-enedioxymethamphetamine (MDMA) and para-chloroamphetamine (PCA), rats were given multiple doses (8 x 30 mg/kg s.c.) of alpha-ethyltryptamine acetate. Serotonin and 5-hydroxyindole acetic acid (5-HIAA) levels and the number of 5-HT uptake sites (determined from [3H]paroxetine binding) were significantly decreased in frontal cortex samples at one week killing. A significant decrease in 5-HT and 5-HIAA levels was also observed in rat hippocampal samples. The results provide evidence that alpha-ethyltryptamine may induce serotonin neurotoxicity similar to that of MDMA and PCA.

Animals↗
PubMed1991

Serotonin neurotoxicity in rats after combined treatment with a dopaminergic agent followed by a nonneurotoxic 3,4-methylenedioxymethamphetamine (MDMA) analogue.

There is increasing evidence linking dopamine (DA) to the long-term serotonergic (5-HT) neurotoxic effects of certain substituted amphetamines such as 3,4-methylenedioxymethamphetamine (MDMA). The present study was undertaken to examine the importance of DA metabolism, uptake inhibition and release in the long-term effects of these drugs by combining various dopaminergic agents with an analogue of MDMA that had low neurotoxic liability, namely 5,6-methylenedioxy-2-aminoindan (MDAI). Monoamine and metabolite levels and the number of 5-HT uptake sites (using [3H]paroxetine binding) were determined 3 hours or 1 week after treatments. Combining the monoamine oxidase inhibitors, clorgyline (MAOA selective) or deprenyl (MAOB selective) with MDAI did not result in any long-term reductions of serotonergic markers. Similarly, combining the DA uptake inhibitor GBR-12909 with MDAI did not result in any long-term changes in monoamine levels at 1 week. In contrast, a single pretreatment of posttreatment with the nonvesicular DA releaser S-amphetamine and MDAI resulted in small but significant long-term changes in monoamine levels. More importantly, if a subacute dosing regimen (every 12 hours for 4 days) was utilized, the combination of S-amphetamine with MDAI resulted in a marked long-term decrease in the levels of cortical, hippocampal and striatal 5-HT, 5-HIAA and the number of 5-HT uptake sites. The results are discussed in terms of the significance of DA and especially nonvesicular DA release in the long-term effects of MDMA-like drugs.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1991

2,3-Dihydrobenzofuran analogues of hallucinogenic phenethylamines.

Two 2,3-dihydrobenzofuran analogues of hallucinogenic amphetamines were prepared and evaluated for activity in the two-lever drug-discrimination paradigm in rats trained to discriminate saline from LSD tartrate (0.08 mg/kg) and for the ability to displace [125I]-(R)-DOI [( 125I]-(R)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane) from rat cortical homogenate 5-HT2 receptors. The compounds, 1-(5-methoxy-2,3-dihydrobenzofuran-4-yl)-2-aminopropane (6a) and its 7-brominated analogue 6b, possessed activity comparable to their conformationally flexible counterparts 1-(2,5-dimethoxyphenyl)-2-aminopropane (3) and its 4-bromo derivative DOB (5), respectively. The results suggest that the dihydrofuran ring in 6a and 6b models the active conformation of the 5-methoxy groups in 3 and 5. Free energy of binding, derived from radioligand displacement KA values, indicated that addition of the bromine in either series contributes 2.4-3.2 kcal/mol of binding energy. On the basis of surface area of the bromine atom, this value is 2-3 times higher than would be expected on the basis of hydrophobic binding. Thus, hydrophobicity of the para substituent alone cannot account for the dramatic enhancement of hallucinogenic activity. Although this substituent may play a minor role in orienting the conformation of the 5-methoxy group in derivatives such as 4 and 5, there appears to be some other, as yet unknown, critical receptor interaction.

Animals↗
PubMed1991

[Treatment of chemotherapy-induced leukocytopenia with acupuncture and moxibustion].

The effects of acupuncture and moxibustion on 376 cases of chemotherapy-induced leukocytopenia was observed in patients with malignant tumors in the intermediary and advanced stages. Findings revealed that the total effect in 121 cases (88.4%) occurred in the group treated with acupuncture and moxibustion with warming needle; while the total effect in 221 cases (90.9%) was in the group treated with moxibustion with ignited moxa cone. A comparison made between the 2 groups showed no significant difference (P greater than 0.05). The total effective rate was 38.2% when compared with the control group using batylalcohol and pentoxyl and so the difference was significant (P less than 0.01). Analysis found that with patients having higher basic WBC value, the effect would be higher. Conversely, those who had lower basic value in their WBCs, the expected effect would be lower. These findings suggest that acupuncture and moxibustion in raising the effect on the white cells were influenced by the extent to which the bone marrow was inhibited, having no relevance to the kind of disease, the chemotherapy regime, and the treatment course which the patient was in.

Acupuncture Therapy↗
PubMed1990

Behavioral, biochemical and neurotoxicological actions of the alpha-ethyl homologue of p-chloroamphetamine.

The present set of experiments was designed to examine the effects of extension of the alpha-methyl of p-chloroamphetamine (PCA) to an alpha-ethyl. Therefore, the alpha-ethyl homologue of PCA, 1-(4-chlorophenyl)-2-aminobutane (CAB), was compared to PCA in a number of pharmacological assays. CAB was 2-fold less potent than PCA at inhibiting synaptosomal uptake of [3H]5-hydroxytryptamine ([3H]5-HT), and 5-fold less potent at inhibiting uptake of [3H]dopamine ([3H]DA). In drug discrimination assays, CAB was approximately 3-fold less potent than PCA in animals trained to discriminate 3,4-methylenedioxymethamphetamine (MDMA) or its alpha-ethyl homologue, S-(+)-N-methyl-1-(1,3-benzodioxol-5-yl)-2-butanamine (S-(+)-MBDB), from saline. Monitoring with in vivo microdialysis, 10 mg/kg of PCA caused a large increase in extracellular DA and a significant decrease in 3,4-dihydroxyphenylacetic acid (DOPAC) in the striatum. In contrast, 11 mg/kg CAB caused no increase and 22 mg/kg CAB caused only a slight increase in extracellular DA. Both doses of CAB caused a decrease in extracellular DOPAC. The potential 5-HT neurotoxicity of CAB was examined by measuring monoamine and metabolite levels and [3H]paroxetine binding at one week following acute doses. A 10 mg/kg dose of PCA caused an 80% decrease in cortical and hippocampal serotonergic markers, while an equimolar dose of CAB decreased only hippocampal 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) levels. However, 22 mg/kg of CAB produced a 20-40% decrease in all serotonergic markers. Thus, extension of the alpha-alkyl significantly decreases the dopaminergic effects of PCA. The similar decrease in relative 5-HT neurotoxicity and the decreased ability to alter dopaminergic systems in vivo and in vitro supports the involvement of DA in the neurotoxicity of PCA.

3,4-Methylenedioxyamphetamine↗
PubMed1989

[Studies on the chemical constituents of Curcuma kwangsiensis].

A new sesquiterpene lactone named gweicurculactone, along with beta-sitosterol, germacrone, daucosterin and palmitic acid, was isolated from Curcuma kwangsiensis. Its structure has been confirmed by means of spectral and X-ray diffraction analysis.

Azulenes↗
PubMed1986

[Intraoperative cytodiagnosis of lung masses by fine needle aspiration].

The results of intraoperative cytodiagnosis by fine needle aspiration of 51 cases with lung masses are presented. The diagnosis of benign lesion in 17/51 cases and malignancy in 34/51 cases was established by cytology. The accuracy of this cytopathologic diagnosis was 100% in our series. In 34 cases with malignant lung tumors, the accuracy, as compared with histological diagnosis in cell type, was 84.2%. At thoracotomy, this approach is easy, safe and rapid and without any complication for undetermined pulmonary lesions. In some cases with a deep lesion, this approach has proved to be most useful to avoid a blind major pulmonary resection. We believe that intraoperative cytodiagnosis of lung masses by fine needle aspiration is a valuable supplementary diagnostic measure for pulmonary neoplasms.

Adenocarcinoma↗
PubMed1983

[Clinical comparison of four types of IUDs made in China].

In order to compare the clinical efficacy of 4 types China made IUDs, this paper reported the study of a total of 1227 cases who, from January 1973 to June 1975, had used 1 of the 4 types of IUDs -- the stainless steel ring, metallic plastic mixed ring, metallic and silastic copper-shaped devices. The study was not a random allocation but was done, 1 type by 1, during the period. Life table method and logrank test were used to calculate and analyze the different events among these 4 types. 1147 cases were followed up for more than 5 years. The 5-year followup rate was 93.48%. Patients using these 4 types were comparable among themselves since the distribution of their age, gravida, para, and time of insertion were the same or quite similar. Study results were as follows: the cumulative pregnancy rates of the 2 copper V-shaped IUDs were significantly lower than that of the steel and mixed ring (p0.01); the cumulative expulsion rate of the steel ring was comparatively high, but there was no statistical difference compared with the others; bleeding was the main cause of medical removals; there was a higher cumulative medical removal rate of the V-shaped than that of the ring-shaped and also a significant difference between them (p0.01). However, at every year, the year-cumulative continuation rates were similar despite the difference of the events of discontinuation rates. The fact that 51.72-62.29% of the subjects continued to wear these IUDs indicated that the efficacy of the 4 types of IUDs was satisfactory even after a 5-year course.

Birth Rate↗