Biomedical subjects

Li Huang

Publications and source records attributed to Li Huang.

98 records · Page 6Linked to original sources

PubMed2002

Molecular targets of anti-HIV-1 triterpenes.

Pentacyclic triterpenes have been found in many plants and may be isolated from any part of the plant. Triterpene derivatives were shown to have biological activities including anti-HIV-1 and anti-cancer activities. The modes of action of the anti-HIV-1 triterpenes have been reported to be associated with the virus entry, reverse transcription, virus assembly and maturation. This review will focus on the mechanisms of action of anti-HIV triterpenes and the structural features that contribute to their anti-HIV-1 activity and site of action.

Anti-HIV Agents↗

PubMed2002

[Relationship between the quantities of virus and the models of serologic markers in patients infected with HBV].

OBJECTIVE: To explore the relationship between the quantities of HBV and the models of serologic markers. METHODS: Real-time fluorescent quantitative PCR was used to measure the HBV DNA and ELISA was used to detect the antigen/antibody of HBV. RESULTS: The patients whose HBV copies were more than 10(3)/ml accounted for 87.3%, whose copies were more than 10(7)/ml accounted for 66.7% among the HBsAg and HBeAg -positive patients. The patients whose HBV copies were less than 10(3)/ml accounted for 74.5%, whose HBV copies were more than 10(7)/ml accounted for 8.3% among the HBeAg-negative patients. The HBV copies of HBeAg-positive patients were significantly more than HBeAg-negative patients (P<0.01). The HBV copies of anti-HBe-negative patients were significantly more than anti-HBe-positive patients (P<0.01). The HBV DNA was detected in some HBsAg-negative patients. One patient's HBV copies were as high as 1.59 10(9)/ml. CONCLUSIONS: The HBV copies of HBeAg-positive patients are significantly more than HBeAg-negative patients, The HBV copies of anti-HBe-negative patients are significantly more than the anti-HBe-positive patients. However, some HBeAg-positive patient's HBV copies are very low, and some HBeAg-negative patient's HBV copies are very high. HBV DNA even could be detected in some HBsAg-negative patients. It is difficult to judge accurately the quantities of HBV and infectivity according to the serologic markers for a specific patient.

Adolescent↗

PubMed2002

[Experimental study on effect of jiangya maijing liquid on spontaneous hypertension rats fed with high lipid diet].

OBJECTIVE: To observe and identify the effect of Jiangya Maijing Liquid (JYMJL) on spontaneous hypertension rats (SHR) fed with high lipid diet in antagonizing hypertension and hyperlipidemia and improving pathological changes of kidney. METHODS: Forty-two SHR were divided into 5 groups, except Group A, the Groups B-E were fed with high lipid diet, and Group C, D and E was treated with JYMJL, western drug and Niuhuang Jiangya pill respectively. Besides, Group F was set up for control with normal rats fed by normal diet. The changes of blood pressure (BP), biological indices and renal pathology were observed in the 14 weeks' period of observation. RESULTS: (1) BP raised significantly in Group A and B, it became stable in Group C from the 5th week on and was lower than the BP in other groups (P < 0.01). BP in Group F was not changed; (2) The highest level of nitric oxide (NO) was shown in Group F, and that in Group B and E was lower than that in Group C and D; (3) Level of cholesterol was lower in Group A and F than that in Group C, D and E (P < 0.01), and that in Group C was lower than that in Group B and E (P < 0.01 and P < 0.05 respectively); (4) Pathologic examination on kidney showed that no change was found in Group F, the most severe change was shown in Group B among Group B-E, and the improvement after treatment in Group C was better than that in group B (P < 0.01). CONCLUSION: (1) Condition of disease in rats with hypertension complicated with hyperlipidemia was more severe than that with simple hypertension; (2) JYMJL could restrain the developing of hypertension in SHR, the mechanism may be related with the raising of NO; (3) JYMJL has effect of lowering blood lipid; (4) JYMJL has kidney protective effect, it could alleviate the pathological changes in kidney by way of lowering BP and blood lipid.

Animals↗

PubMed2001

Differential Gene Expression Following Noise Trauma in Birds and Mammals.

Acoustic overstimulation has very different outcomes in birds and mammals. When noise exposure kills hair cells in birds, these cells can regenerate and hearing will recover. In mammals, however, the hair cell loss, and resulting hearing loss, is permanent. Changes in gene expression form the basis for important biological processes, including repair, regeneration, and plasticity. We are therefore using a battery of molecular approaches to identify and compare changes in gene expression following noise trauma in birds and mammals. Both differential display and subtractive hybridisation were used to identify genes whose expression increased in the chick basilar papilla immediately following exposure to an octave band noise (118 dB, centre frequency 1.5 kHz) for 4-6 hr. Among those upregulated genes were two involved in actin signalling: the CDC42 gene encoding a Rho GTPase, and WDR1, which encodes a protein involved in actin dynamics. A third gene, UBE3B, encodes an E3 ubiquitin ligase involved in protein turnover. A fourth gene encodes a cystein-rich secreted protein that may interact with calcium channels. To examine the mammalian response, gene microarrays on nylon membranes (Clontech Atlas Gene Arrays) were used to examine global changes in gene expression 30 minutes after TTS (110 dB broadband noise 50% duty cycle) or PTS (125 dB, 100% duty cycle) noise overstimulation (each for 90 minutes) in the rat cochlea. Several genes, including classic immediate early response genes such as c-fos, EGR1/NGFI-A, and NGFI-B, were upregulated at this early time point following the PTS exposure, but were not upregulated following the TTS exposure.

Journal Article↗

PubMedDate not supplied

Cloning and characterization of rat spermatid protein SSP411: a thioredoxin-like protein.

In an attempt to identify new sperm-specific genes that are involved in sperm maturation, fertilization, and embryo development, such as the mammalian ortholog of the sperm-supplied protein gene, spe-11, in Caenorhabditis elegans, we cloned and characterized a new spermatid-specific protein gene, ssp411, from adult rat testes. The ssp411 cDNA shared >85% sequence identity with an unnamed human protein, FLJ21347, and an uncharacterized mouse testicular protein called transcript increased in spermiogenesis 78 (TISP78). A 2.8-kb ssp411 mRNA was expressed in a testis-specific and age-dependent manner; the mRNA was evident at 28 days and remained at high levels throughout adulthood. An SSP411 protein of molecular weight 88 000 was detected in testicular extracts by Western blot analysis. Ssp411 mRNA and SSP411 protein, as analyzed by in situ hybridization and immunohistochemistry, were both expressed in a stage-dependent fashion during the cycle of the seminiferous epithelium. The ssp411 mRNA was predominantly localized to round and elongated spermatids, with maximal expression at stages VII-XII. The SSP411 protein was mainly observed in elongated spermatids and reached its highest levels during stages V-VI. A conserved thioredoxin-like domain was detected in the N-terminal region of SSP411 and its orthologs. An analysis of the predicted 3-dimensional structural modeling and folding pattern further suggested that SSP411 is identifiable as a member of thioredoxin family. In summary, we have identified a new rat spermatid protein gene, ssp411, and its orthologs in human and mouse and demonstrated that SSP411 might belong to a testis-specific thioredoxin family. This suggests that SSP411 may play a role in sperm maturation, fertilization, and/or embryo development, as has been shown in thioredoxin family.

Amino Acid Sequence↗

PubMedDate not supplied

Colorimetric diffusion-reflection imaging high-throughput analysis of organic or inorganic compounds.

A colorimetric diffusion-reflection imaging (CDRI) high-throughput analytical technology was developed for library analysis. In the investigation, quartz sands were employed as light diffusion-reflection media. Inorganic and organic compounds with characteristic absorption bands in visible light could be quantified by this method. In the current investigation, compounds such as CrCl3, KMnO4, methylene blue, and acrolein were employed as substrates, and the UV spectrometer and traditional GC (with thermal conductivity detector) were employed to check the reliability of our CDRI technology. The current technology is capable of analyzing more then 100 samples simultaneously. Relative errors below 10% were achieved.

Acrolein↗

PubMedDate not supplied

Effects of epitopes combination and adjuvants on immune responses to anti-Alzheimer disease DNA vaccines in mice.

Alzheimer disease (AD) is a neurodegenerative disorder characterized by neuropathological hallmarks including deposits of the beta-amyloid peptide (AssP). Studies have shown that immunization with Abeta42 peptide reduces both the spatial memory impairments and Alzheimer disease-like neuropathologic changes in Alzheimer disease transgenic mice, but can cause side effect of a cell-mediated autoimmune meningoencephalitis. Recently, some studies showed that DNA vaccination could be used to generate an antibody response to Abeta without the adverse cell-mediated immune effect. In the current study, we generate four DNA vaccine plasmids (pV-GE1, pV-GE2, pV-GE3, and pV-GE4) against Alzheimer disease by separately fusing Abeta epitope sequences (coding for EFGH, DAEFGH, EFGH+EFGH, and EFGH+DAEFGH) with IgG heavy chain coding region of mouse. Meanwhile, the full-length gene Abeta encoding plasmid (pV-Abeta), empty vector (pVAX) and synthetic AssP were also included as control. The sera of BALB/c mice immunized via intramuscular with plasmids and peptide were tested by indirect ELISA for auto-AssP immunoreactivity. The results showed that all the DNA vaccine plasmids induced AssP-specific antibodies; moreover pV-GE2 and pV-Abeta constructs elicited higher antibody titers than other constructs (P < 0.05). To further enhance the immune response, GM-CSF encoding plasmid (pGM-CSF) and purified BCG-DNA were used as molecular adjuvants. BCG-DNA could enhance humoral and cellular immune responses simultaneously and did not alter the phenotype of the immune responses, whereas pGM-CSF showed no obvious effect on immune response. These results suggest that this immunization strategy of using Abeta epitope encoding plasmid plus BCG-DNA adjuvant may serve as the basis for developing anti-Alzheimer disease vaccines.

Alzheimer Vaccines↗

PubMedDate not supplied

One internal standard for multiple analytes: a limit and solution.

The use of a single internal standard (ephedrine-d5) as the basis for calculations of the concentrations of both the major and the minor alkaloids leads to incorrect results from variabilities in the solid-phase extraction (SPE) of the ephedra alkaloids. Because the SPE column is overloaded by ephedrine, the recovery of the internal standard, which is dependent on the dilution factor, is decreased. On the other hand, the recoveries of the minor alkaloids (methylephedrine, methylpseudoephedrine, norephedrine, and norpseudoephedrine) stay high because these compounds are less concentrated and do not overload the SPE column. Consequently, the recovery factors for the major and minor alkaloids are different, or the results are incorrect if the same recovery factor is used.

Ephedra↗