PubMed Health⌕ Search

Biomedical subjects

Hui Zhou

Publications and source records attributed to Hui Zhou.

At least 109 records · Page 6Linked to original sources
PubMed2004

[Effect of yiqijiedu granule on the implanted-tumor protein expression in nasopharyngeal carcinoma].

OBJECTIVE: To investigate the inhibitory mechanism of Yiqijiedu granule on the implanted-tumor growth of nasopharyngeal carcinoma in nude mice. METHODS: Twenty nude mice were injected nasopharyngeal carcinoma cells (HNE1), with 5 x 10(6) cells for a nude mouse. Implanted-tumors grew for 20 d, whose volume reached 1 cm x 1 cm x 1 cm. These nude mice were divided into 2 groups: Yiqijiedu group and control group. The Yiqijiedu group was given Yiqijiedu granule, and the control was given normal saline for 30 d, and then were killed. The volume and weight of implanted-tumors were measured. A 100-mg tissue from implanted-tumors was used to extract total protein by current methods, in which the proteins were separated by two-dimension electrophoresis and stained by silver, and protein profiles of implanted-tumors were obtained. Different proteins in the profiles were analyzed by ImageMaster 2D Elite 4.01. Nineteen different proteins, in which 4 expressed in the Yiqijiedu group, 4 expressed in the control, and the other 11 were differently expressed at 5 folds, were identified by MALDI-TOF-MS. RESULTS: The Yiqijiedu granule could inhibit the growth of implanted-tumors. The volume and weight of implanted-tumors in the Yiqijiedu group were (0.207 +/- 0.023) cm3 and (0.132 +/- 0.021) g respectively, and that of the control was (1.342 +/- 0.298) cm3 and (1.017 +/- 0.015) g ( P < 0.05). The inhibitory rate was 84.58%. The analyses of two-dimension electrophoresis and ImageMaster 2D Elite 4.01 showed that there were 567 +/- 49 protein dots in the Yiqijiedu group and 679 +/- 59 in the control. We found 243 proteins were dys-regulated, of which 112 proteins were observed, up-regulated and the other 131 proteins were down-regulated. MALDI-TOF-MS and Database analysis showed that the high expression proteins were HKR2 protein, 10 Phosphoribosyl pyrophosphate synthetase, TNFR superfamily member, and Apoptosis regulator. The lower expression proteins were Fibulin-3, Zinc finger protein 266, Carboxy terminus of HSP70-interacting protein, et al. CONCLUSION: Yiqijiedu granule could inhibit the growth of nasopharyngeal carcinoma, which may be associated with those proteins regulated by itself.

Animals↗
PubMed2003

Huntingtin forms toxic NH2-terminal fragment complexes that are promoted by the age-dependent decrease in proteasome activity.

Although NH2-terminal mutant huntingtin (htt) fragments cause neurological disorders in Huntington's disease (HD), it is unclear how toxic htt fragments are generated and contribute to the disease process. Here, we report that complex NH2-terminal mutant htt fragments smaller than the first 508 amino acids were generated in htt-transfected cells and HD knockin mouse brains. These fragments constituted neuronal nuclear inclusions and appeared before neurological symptoms. The accumulation and aggregation of these htt fragments were associated with an age-dependent decrease in proteasome activity and were promoted by inhibition of proteasome activity. These results suggest that decreased proteasome activity contributes to late onset htt toxicity and that restoring the ability to remove NH2-terminal fragments will provide a more effective therapy for HD than inhibiting their production.

Animals↗
PubMed2003

Alternative splicing of cGMP-dependent protein kinase I in angiotensin-hypertension: novel mechanism for nitrate tolerance in vascular smooth muscle.

Nitrate tolerance (NT) in hypertension is attributed to reduced activity of soluble guanylyl cyclase (sGC). We examined NT in basilar artery vascular smooth muscle cells (VSMCs) from control rats, rats infused with angiotensin II (Ang; 240 microg/kg per hour for 4 days), which were normotensive, and Ang-hypertensive rats (AHR; 240 microg/kg per hour for 28 days). Ca2+-activated K+ (Maxi-K) channels in VSMCs from AHR showed reduced activation by NO donor, consistent with NT. The concentration-response relationship for 8-Br-cGMP was shifted 2.5-fold to the right, indicating that abnormal sGC alone could not account for NT. Inside-out patches from AHR showed normal activation with exogenous cGMP-dependent protein kinase I (cGKI), suggesting no abnormality downstream of cGKI. We hypothesized that the reduction in apparent affinity of 8-Br-cGMP for cGKI in AHR might be due to a change in relative amounts of cGKIalpha versus cGKIbeta, since cGKIbeta is less sensitive to cGMP activators than cGKIalpha. This was substantiated by showing the following in AHR: (1) reduced effect of the cGKIalpha-selective activator 8-APT-cGMP; (2) reduced total cGKI protein (both isoforms), but an increase in cGKIbeta protein in quantitative immunofluorescence and Western blots; (3) similar changes in cGKI isoforms immunoisolated with Maxi-K channels; and (4) a large increase in cGKIbeta mRNA and a decrease in cGKIalpha mRNA in real-time PCR and Northern blots. Upregulation of cytosolic cGKIbeta was evident 4 days after Ang infusion, before development of hypertension. Our data identify a functional role for cGKIbeta in VSMCs previously ascribed exclusively to cGKIalpha. Ang-induced alternative splicing of cGKI represents a novel mechanism for reducing sensitivity to NO/cGMP.

Alternative Splicing↗
PubMed2003

Trans-cellular proliferating cell nuclear antigen gene activation in cerebral vascular smooth muscle by endothelial oxidative injury in vivo.

OBJECTIVE: This study was undertaken to assess the role of vascular smooth muscle cell (VSMC) Ca2+ channels and Ca2+/calmodulin-dependent protein kinase II (CaMKII) in gene regulation after oxidative endothelial injury (OEI). METHODS AND RESULTS: OEI was produced by infusion of Na fluorescein (NaFluo) photoactivated by UV light immediately before intravenous injection. Posterior cerebral arteries were studied using immunofluorescence imaging, Western blotting, or patch clamping of isolated cells. After infusion of photoactivated NaFluo, but not NaFluo, (1) superoxide dismutase-1 (SOD-1) was upregulated in endothelium, consistent with oxidant stress; (2) the fraction of VSMC nuclei labeled for proliferating cell nuclear antigen (PCNA) increased 7-fold at 6 hours, preceded by a several-fold increase in nuclear phospho-cAMP-response element binding protein, with PCNA upregulation prevented by pretreatment with polyethylene glycol (PEG)-SOD; (3) in VSMCs, phospho-CaMKII increased 20-fold 5 minutes after OEI, with a 2-fold increase in peak Ca2+ channel currents; and (4) changes in cAMP-response element binding protein and PCNA were blocked by systemic administration of lipophilic (nifedipine) or hydrophilic (amlodipine) 1,4-dihydropyridine Ca2+ channel blockers, the calmodulin inhibitor trifluoperazine, or the CaMKII inhibitor KN-93, with none of these agents preventing SOD-1 upregulation in endothelium. CONCLUSIONS: Activation of VSMC Ca2+ channels and CaMKII is a key early signaling event required for upregulation of PCNA gene expression in VSMCs after oxidative injury to endothelium.

Animals↗
PubMed2003

The complete mitochondrial genome of the Chinese giant salamander, Andrias davidianus (Amphibia: Caudata).

The mitochondrial genome of the Chinese giant salamander Andrias davidianus was isolated using the long-and-accurate polymerase chain reaction (LA PCR) method. The sequencing work adopted the shotgun strategy accompanying with seven internal primers to cover the gaps where overlapping clones were not available. The entire mtDNA sequence is 16,503 bp long, with a gene content of 13 protein-coding, two ribosomal RNA and 22 transfer RNA genes, and order identical to that observed in most other vertebrates except for an additional 318 bp non-coding sequence between tRNA-Thr and tRNA-Pro genes. In order to carry out molecular phylogenetic analyses, all 13 protein sequences deduced from whole mitochondrial genomes for eight vertebrate species (six amphibians, two lobe-finned fishes) were combined to a single data set. This data set was refined by the program Gblocks using a stringent parameter setting and then subjected to MP, ML and NJ analyses. Thus phylogenetic relationships among living amphibians were discussed.

Animals↗
PubMed2003

The high diversity of snoRNAs in plants: identification and comparative study of 120 snoRNA genes from Oryza sativa.

Using a powerful computer-assisted analysis strategy, a large-scale search of small nucleolar RNA (snoRNA) genes in the recently released draft sequence of the rice genome was carried out. This analysis identified 120 different box C/D snoRNA genes with a total of 346 gene variants, which were predicted to guide 135 2'-O-ribose methylation sites in rice rRNAs. Though not exhaustive, this analysis has revealed that rice has the highest number of known box C/D snoRNAs among eukaryotes. Interestingly, although many snoRNA genes are conserved between rice and Arabidopsis, almost half of the identified snoRNA genes are rice specific, which may highlight further the differences in rRNA methylation patterns between monocotyledons and dicotyledons. In addition to 76 singletons, 70 clusters involving 270 snoRNA genes were also found in rice. The large number of the novel snoRNA polycistrons found in the introns of rice protein-coding genes is in contrast to the one-snoRNA-per-intron organization of vertebrates and yeast, and of Arabidopsis in which only a few intronic snoRNA gene clusters were identified. Furthermore, due to a high degree of gene duplication, rice snoRNA genes are clearly redundant and exhibit great sequence variation among isoforms, allowing generation of new snoRNAs for selection. Thus, the large snoRNA gene family in plants can serve as an excellent model for a rapid and functional evolution.

Base Sequence↗
PubMed2003

Mislocalization of eNOS and upregulation of cerebral vascular Ca2+ channel activity in angiotensin-hypertension.

We tested the hypothesis that endothelial dysfunction induced by angiotensin II (Ang-hypertension) would impair regulatory control of vascular smooth muscle L-type Ca2+ channels by endothelial nitric oxide synthase (eNOS). We studied cerebral lenticulostriate arterioles (LSAs) from control rats, from rats infused with Ang (240 microg x kg(-1) x h(-1) SQ x4 days), which were normotensive, and from Ang-hypertensive rats (AHR; 240 microg x kg(-1) x h(-1) x28 days). Patch-clamp measurements on isolated LSA smooth muscle cells (SMCs) showed a significant increase in Ca2+ channel availability with 4- and 28-day infusions versus controls (0.47+/-0.03 and 0.66+/-0.05 vs 0.36+/-0.03 pS/pF, respectively; P<0.01), with Western blots showing no change in channel protein expression, consistent with altered channel regulation. In LSAs from 28-day AHR, 4,5-diaminofluorescein diacetate imaging showed diminished NO production in response to acetylcholine stimulation in vivo, and inhibition of eNOS with NG-nitro-L-arginine methyl ester failed to increase Ca2+ channel availability in isolated SMCs, indicating an abnormality with the eNOS/NO-signaling pathway regulating the channel. Immunofluorescence imaging showed that in 1 of 53, 33 of 109, and 53 of 62 LSAs from controls and from rats with 4- and 28-day infusions, respectively, eNOS was absent from its normal location at the abluminal border and was mislocalized to perinuclear Golgi. Ca2+ channel availability in LSA SMCs from controls and from rats with 4- and 28-day infusions was proportional to the fraction of LSAs showing eNOS mislocalization, but not blood pressure. These data provide the first evidence linking Ang-induced eNOS mislocalization, eNOS dysfunction, and Ca2+ channel upregulation, and they provide novel mechanistic insights into pathological changes in LSAs associated with stroke.

Angiotensin II↗
PubMed2003

Serratene-type triterpenoids from Huperzia serrata.

Seven new and 15 known serratene-type triterpenoids were isolated from the whole plant of Huperzia serrata. The structures of these new triterpenoids were elucidated as 21alpha-hydroxyserrat-14-en-3beta-yl p-dihydrocoumarate (1), 21alpha-hydroxyserrat-14-en-3beta-yl dihydrocaffeate (2), 21alpha-hydroxyserrat-14-en-3beta-yl propanedioic acid monoester (3), 3alpha,21alpha-dihydroxyserrat-14-en-24-oic acid (4), 16-oxo-3alpha,21beta-dihydroxyserrat-14-en-24-al (5), 16-oxo-3alpha,21beta-dihydroxyserrat-14-en-24-oic acid (6), and 16-oxo-21beta-hydroxyserrat-14-en-3alpha-yl acetate (7), respectively, by means of spectroscopic analysis.

Drugs, Chinese Herbal↗
PubMed2003

New epoxyserratanes from Huperzia serrata.

Three new serratane-type epoxytriterpenoids were isolated from the whole plant of Huperzia serrata. The structures of these new compounds were characterized as 14 beta,15 beta-epoxy-3 beta-hydroxyserratan-21 beta-ol (1), 14 beta,15 beta-epoxy-3 beta-hydroxyserratan-21alpha-ol (2), and 14 beta,15 beta-epoxy-3 beta-hydroxyserratan-21alpha-ol-3 beta-O-acetate (3), respectively, on the basis of spectral data and for 1 by single-crystal X-ray analysis.

Drugs, Chinese Herbal↗
PubMed2003

Two new guaianolides and a new daucene derivative from Sinodielsia yunnanensis.

From the roots and rhizomes of Sinodielsia yunnanensis, three new sesquiterpenes were isolated and their structures were established as 5alpha,6beta- H-1(10),3,7(11)-guaiatrien-12,6alpha-olide ( 1), 5alpha,6beta,7beta- H-1(10),3-guaiadien-12,6alpha-olide ( 2) and 5beta-hydroxy-10alpha- O-angeloyl-3-oxodauc-8-ene ( 3) by means of spectroscopic analyses and single-crystal X-ray experiment (for compound 1).

Apiaceae↗
PubMed2003

Acute adenoviral infection of a graft by serotype 35 following renal transplantation.

Adenoviral infections of immunocompetent patients usually present as self-limiting pharyngitis, gastroenteritis, urocystitis, or conjunctivitis. In immunosuppressed patients, development of the illness can be severe, even life-threatening or fatal, and therapeutical intervention is difficult. Previous case reports of adenoviral infections after kidney transplantation have described a symptomatology of hemorrhagic cystitis, fever, renal dysfunction, and rarely fatal systemic dissemination. Here we report on a 46-year-old female renal transplant recipient suffering from adenoviral serotype 35 nephritis of the donor organ 29 days after transplantation. In this case, the main symptoms of the adenoviral infection were high fever and progressive renal failure of the transplanted organ. At the peak of the clinical symptoms, owing to histological and immunohistochemical evaluations of a kidney biopsy, we were able to establish the diagnosis in time so that adequate therapy could be employed. Immunosuppression was reduced and modified, and a self-limiting course of the infection was observed, followed by significant improvement of graft function. Subsequent to histological diagnosis, adenoviral particles were isolated from urine and identified as adenovirus serotype 35. Adenoviral nephritis of the transplanted organ should be considered in the differential diagnosis of persistent anuria after kidney transplantation. Our case highlights the importance of applying all possible diagnostic techniques, including histological evaluation of renal biopsies.

Acute Disease↗
PubMed2003

Adenosine-A2a receptor down-regulates cerebral smooth muscle L-type Ca2+ channel activity via protein tyrosine phosphatase, not cAMP-dependent protein kinase.

Adenosine acting via A2a receptors (A2aR) is a potent cerebral vasodilator that relaxes vascular smooth muscle cells (VSMCs) by a mechanism attributed to activation of cAMP-dependent protein kinase (cAK). We examined effects of adenosine and its mechanism of action on L-type Ca2+ channels in native VSMCs from rat basilar artery. Reverse transcription-polymerase chain reaction and immunofluorescence imaging confirmed transcription and expression of A2aR, and in situ hybridization confirmed presence of mRNA for L-type Cav1.2b channels. In patch-clamp experiments, adenosine down-regulated Ca2+ channel currents in a concentration-dependent manner, with receptor-subtype-specific antagonists [4-(2-[7-amino-2-(2-furyl)[1,2,4]triazolo-[2,3-a][1,3,5]triazin-5-ylamino]ethyl)phenol (ZM-241385) versus 1,3-dipropyl-8-cyclopentyl-1,3-dipropylxanthine] showing that this was caused by action of A2aR. Down-regulation of channel currents was mimicked by stimulation of cGMP-dependent protein kinase (cGK; 8-Br-cGMP) and by inhibition of tyrosine kinase (AG-18) but not by stimulation of cAK [forskolin and 8-bromo-cAMP (8-Br-AMP)]. Down-regulation of currents by the A2aR agonist 2-[p-(2-carboxyeth yl)phenylethylamino]-5'-N-ethyolcarboxamidoadenosine (CGS-21680) was blocked by inhibiting protein tyrosine phosphatase (PTP; orthovanodate and dephostatin), but not by inhibiting cGK (KT-5823 and H-7). Western blots of lysate or of immunoisolated Ca2+ channels from arterial segments incubated with CGS-21680 showed 1) increased phosphorylation of vasodilator-stimulated phosphoprotein that was blocked by inhibiting cAK (KT-5720), consistent with activation of cAK by A2aR; and 2) decreased tyrosine phosphorylation of immunoisolated alpha1c subunit of the Ca2+ channel. Our data show that cAK, although activated, was not germane to down-regulation of Ca2+ channel activity by A2aR, and they delineate a novel signaling mechanism involving reduced tyrosine phosphorylation of Ca2+ channels by A2aR probably caused by PTP activation.

Animals↗
PubMed2003

Inverse scattering for a three-dimensional object in the time domain.

An iterative inverse-scattering approach to reconstruction of electrical parameter distributions of a three-dimensional object by using time-domain field data is presented. The approach is the extension of the forward-backward time-stepping algorithm previously proposed for a two-dimensional object. Numerical examples of simulation data are given to assess the effectiveness of the proposed approach.

Journal Article↗
PubMed2003

Metabolism of SFZ-47 in chicken embryo by liquid chromatography-electrospray ion trap mass spectrometry.

AIM: To develop an alternative method for investigation of drug metabolism by fertilized chicken eggs using 3H-1,2-dihydro-2-(4-methyl-phenylamino) methyl-1-pyrrolizinone (SFZ-47) as a probe drug. METHODS: SFZ-47 (15 mg) was injected into the albumen of eggs from standardized breed chickens previously incubated for 10 d. After 72 h of further incubation, the allantoic liquid was subjected to solid phase extraction on XAD-2 columns and analyzed by liquid chromatography-electrospray ion trap mass spectrometry method. RESULTS: Three major metabolites were identified, namely 4-(3H-1,2-dihydro-1-pyrrolizinone-2-methyl-amino) benzyl alcohol (SFZ-47-OH), 4-(3H-1,2-dihydro-1-pyrrolizinone-2-methyl-amino)-benzoic acid (SFZ-47-COOH), and its glucuronide conjugates. The metabolic profile was little different from that previously found in rabbits and dogs. CONCLUSION: The result demonstrates the usefulness of the fertilized chicken egg as a convenient source of both phase I and phase II metabolites for further metabolism studies of SFZ-47.

Animals↗
PubMed2003

[Characterization of several synthetic and environmental microbial samples by quantitative hybridization].

Limitations of traditional techniques based on selective enrichment and pure-culture isolation make it difficult to precisely characterize the natural microbial ecosystems. Molecular techniques are now being developed and used to address these limitations. Group-specific 16S rRNAs-targeted oligonucleotide probes of different phylogenetic levels are increasingly used to identify and quantify the microbial members in complex environmental samples. Two domain-specific probes were used in this study to elementarily characterize the defined mixtures of RNAs extracted from pure culture (synthetic samples) and a RNA sample obtained from landfill leachate (environmental sample). The results demonstrated that 16S rRNA quantitative hybridization provided an excellent estimation of domain level community composition of these samples, and thus, had a huge potential of usefulness in microbial ecology studies.

Ecology↗
PubMed2003

[Mitochondrial DNA sequence variations of Keriyan in the Taklamakan desert].

The Keriyans live in the center of the Taklamakan desert of Xinjiang Province and they have never married with outsiders. Nobody knows clearly how they immigrated here and who was their origin. The mtDNA hypervariable segment I sequences were sequenced in 75 Keriyans. Seventy-one unique HVS I types were identified, varying at 68 nucleotide positions. Nucleotide diversity and the mean pairwise differences of Keriyan are intermediate between those reported for Eastern and Western populations. Keriyan's low Tajima's D statistics and bell-shaped pairwise-difference distributions can be interpreted as the hallmark of an ancient population expansion. Phylogenetic analysis shows Central Asian populations occupy a position intermediate between the Eastern and Western populations, moreover, the Keriyan presents shorter genetic distances to Xinjiang Uighur and Uighur in other places than to other populations.

Base Sequence↗
PubMed2003

[The compare disquisition of the collateral ligaments: normal and pathologic appearances on MRI].

OBJECTIVE: To evaluate the MR findings of normal and abnormal collateral ligament and the meaning of medical jurisprudence appraisal. METHODS: The MR findings of 12 normal and 13 surgically confirmed injured collateral ligaments were retrospectively reviewed and compared. RESULTS: The normal tibial and fibular collateral ligaments were hypointense string on both T1 and T2 coronal MR images, with average length of 6.8 cm for tibial collateral ligament and 5.7 cm for fibular collateral ligament.13 collateral ligaments were injured, including 6 tibial and 3 fibular collateral ligaments. Two cases(4 ligaments) had both tibial and fibularcollateral ligaments injuries. The injury of collateral ligament was classified as: Grade I(5 ligaments), Grade II(5 ligaments), and Grade III(3 ligaments). The complications of anterior cruciate ligament sprains(3 cases), posterior cruciate ligament sprains(4 cases), meniscal tear(2 cases) were found in 7 patients(63.6%). CONCLUSION: Coronal MR imaging can clearly demonstrate the structure of the knee collateral ligaments, accurately diagnose and classify the ligament injury, and correctly detect the complications, MRI is very valuable for medical jurisprudence appraisal.

Adult↗