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Hua Wang

Publications and source records attributed to Hua Wang.

At least 55 records · Page 3Linked to original sources
PubMed2006

Synthesis of a precursor dipeptide of RGDS (Arg-Gly-Asp-Ser) catalysed by the industrial protease alcalase.

Synthesis of Bz-Arg-Gly-NH(2) (N-benzoylargininylglycinamide) [a precursor dipeptide of RGDS (Arg-Gly-Asp-Ser)] catalysed by protease in water/organic co-solvent systems was studied. Starting substrates were N-benzoyl-L-arginine ethyl ester hydrochloride (acyl donor) and glycinamide (nucleophile). Acetonitrile was selected as the organic solvent. Alcalase, an industrial alkaline protease, was applied to the synthesis of the target dipeptide. The conditions of the synthesis reaction were optimized by examining the effects of several factors, including water content, temperature, pH, molar ratio of the substrates and reaction time, on the yield of Bz-Arg-Gly-NH(2). The optimum conditions were established to be pH 10.0, 45 degrees C, in acetonitrile/0.1 M Na(2)CO(3)/NaHCO(3) buffer system (90:10, v/v) for 1 h with a dipeptide yield of 82.9%.

Catalysis↗
PubMed2006

Alcalase-catalyzed, kinetically controlled synthesis of a precursor dipeptide of RGDS in organic solvents.

The protease-catalyzed, kinetically controlled synthesis of a precursor dipeptide of RGDS, Z-Asp-Ser-NH2 in organic solvents was studied. Alcalase, an industrial alkaline protease, was used to catalyze the synthesis of the target dipeptide in water-organic cosolvents systems with Z-Asp-OMe as the acyl donor and Ser-NH2 as the nucleophile. Acetonitrile was selected as the organic solvent from acetonitrile, ethanol, methanol, DMF, DMSO, ethyl acetate, 2-methyl-2-propanol, and chloroform tested under the experimental conditions. The conditions of the synthesis reaction were optimized by examining the effects of several factors, including water content, temperature, pH, and reaction time on the Z-Asp-Ser-NH2 yields. The optimum conditions are pH 10.0, 35 degrees C, in acetonitrile/Na2CO3-NaHCO3 buffer system (85:15, v/v), 6 h, with a dipeptide yield of 75.5%.

Acetonitriles↗
PubMed2006

New synthetic route for RGD tripeptide.

A new route was employed to synthesize RGD. First, Gly-Asp dipeptide was synthesized by a novel chemical method in two steps, including chloroacetylation of L-aspartic acid and ammonolysis of chloroacetyl L-aspartic acid. Second, Nalpha-Z- L-Arginine was reacted with Gly-Asp to synthesize RGD by the N-carboxyanhydride method. Less protected amino acids were used in this synthesis. This method possessed advantages of low cost, simplicity, and rapidity with a reasonable yield of 62% calculated from arginine. In addition, compared with the above method, a conventional solid phase method was also used to synthesize RGD, the yield was 75% calculated from the first amino acid anchored to resin.

Chromatography, High Pressure Liquid↗
PubMed2006

Progression of regulatory gene expression states in fetal and adult pro-T-cell development.

Precursors entering the T-cell developmental pathway traverse a progression of states characterized by distinctive patterns of gene expression. Of particular interest are regulatory genes, which ultimately control the dwell time of cells in each state and establish the mechanisms that propel them forward to subsequent states. Under particular genetic and developmental circumstances, the transitions between these states occur with different timing, and environmental feedbacks may shift the steady-state accumulations of cells in each state. The fetal transit through pro-T-cell stages is faster than in the adult and subject to somewhat different genetic requirements. To explore causes of such variation, this review presents previously unpublished data on differentiation gene activation in pro-T cells of pre-T-cell receptor-deficient mutant mice and a quantitative comparison of the profiles of transcription factor gene expression in pro-T-cell subsets of fetal and adult wildtype mice. Against a background of consistent gene expression, several regulatory genes show marked differences between fetal and adult expression profiles, including those encoding two basic helix-loop-helix antagonist Id factors, the Ets family factor SpiB and the Notch target gene Deltex1. The results also reveal global differences in regulatory alterations triggered by the first T-cell receptor-dependent selection events in fetal and adult thymopoiesis.

Aging↗
PubMed2006

Melatonin protects against lipopolysaccharide-induced intra-uterine fetal death and growth retardation in mice.

Lipopolysaccharide (LPS) has been associated with adverse developmental outcomes, including intra-uterine fetal death (IUFD) and intra-uterine growth retardation (IUGR). However, the exact mechanism for LPS-induced IUFD and IURD remains unclear. LPS stimulates macrophages to generate reactive oxygen species (ROS). Therefore, we hypothesize that ROS may be involved in LPS-induced IUFD and IURD. Melatonin is a powerful endogenous antioxidant. In this study, we investigated the protective effects of melatonin on LPS-induced IUFD and IURD in ICR mice. All pregnant mice except controls received an intraperitoneal (75 microg/kg, i.p.) injection of LPS on gestational day (gd) 15-17. The experiment was carried out in two different modes. In mode A, the pregnant mice received two doses of melatonin within 24 hr, one (5 or 10 mg/kg) injected immediately after LPS and the other (5 or 10 mg/kg) injected at 3 hr after LPS. In mode B, the pregnant mice were pretreated with 10 mg/kg of melatonin 18 hr before LPS and then received two doses of melatonin in 24 hr, one (10 mg/kg) injected immediately after LPS and the other (10 mg/kg) injected 3 hr after LPS. The number of live fetuses, dead fetuses and resorption sites were counted on gd 18. Live fetuses in each litter were weighed. Crown-rump and tail lengths were examined and skeletal development was evaluated. Results showed that post-treatments with melatonin significantly attenuated LPS-induced IUFD in a dose-dependent manner. Surprisingly, pre- plus post-treatments with melatonin almost blocked LPS-induced IUFD. In addition, both post-treatments and pre- plus post-treatments with melatonin significantly alleviated LPS-induced decreases in crown-rump and tail lengths and reversed LPS-induced skeletal developmental retardation. However, melatonin had little effect on LPS-induced decrease in fetal weight. Furthermore, pre- plus post-treatments with melatonin significantly attenuated LPS-induced lipid peroxidation in maternal liver. These results indicate that melatonin protects against LPS-induced IURD and IUGR via counteracting LPS-induced oxidative stress.

Animals↗
PubMed2006

Antimicrobial activities of cinnamon oil and cinnamaldehyde from the Chinese medicinal herb Cinnamomum cassia Blume.

Both Cinnamomum verum J.S. Presl. and Cinnamomum cassia Blume are collectively called Cortex Cinnamonmi for their medicinal cinnamon bark. Cinnamomum verum is more popular elsewhere in the world, whereas C. cassia is a well known traditional Chinese medicine. An analysis of hydro-distilled Chinese cinnamon oil and pure cinnamaldehyde by gas chromatography/mass spectrometry revealed that cinnamaldehyde is the major component comprising 85% in the essential oil and the purity of cinnamaldehyde in use is high (> 98%). Both oil and pure cinnamaldehyde of C. cassia were equally effective in inhibiting the growth of various isolates of bacteria including Gram-positive (1 isolate, Staphylococcus aureus), and Gram-negative (7 isolates, E. coli, Enterobacter aerogenes, Proteus vulgaris, Pseudomonas aeruginosa, Vibrio cholerae, Vibrio parahaemolyticus and Samonella typhymurium), and fungi including yeasts (four species of Candida, C. albicans, C. tropicalis, C. glabrata, and C. krusei), filamentous molds (4 isolates, three Aspergillus spp. and one Fusarium sp.) and dermatophytes (three isolates, Microsporum gypseum, Trichophyton rubrum and T. mentagraphytes). Their minimum inhibition concentrations (MIC) as determined by agar dilution method varied only slightly. The MICs of both oil and cinnamaldehyde for bacteria ranged from 75 microg/ml to 600 microg/ml, for yeasts from 100 microg/ml to 450 microg/ml, for filamentous fungi from 75 microg/ml to 150 microg/ml, and for dermatophytes from 18.8 microg/ml to 37.5 microg/ml. The antimicrobial effectiveness of C. cassia oil and its major constituent is comparable and almost equivalent, which suggests that the broad-spectrum antibiotic activities of C. cassia oil are due to cinnamaldehyde. The relationship between structure and function of the main components of cinnamon oil is also discussed.

Acrolein↗
PubMed2006

Overexpression of IGFBP5, but not IGFBP3, correlates with the histologic grade of human diffuse glioma: a tissue microarray and immunohistochemical study.

Insulin-like growth factor binding proteins (IGFBPs) comprise a family of proteins that bind and regulate the functions of IGFs. One of the IGFBPs, IGFBP2, has recently been shown to be overexpressed in glioblastoma. Overexpression of IGFBP2 contributes to the invasiveness of glioblastoma and correlates with histologic grade and survival in patients with diffuse gliomas, suggesting that IGFBP2 expression may contribute to the glioma formation and/or progression. The expression of other IGFBP family members in gliomas has, however, not been examined in detail. This study was designed to evaluate the expression of IGFBP3 and IGFBP5 in diffuse gliomas using immunohistochemistry applied to a tissue array constructed from 259 gliomas, including ten gliosarcomas. Expression of IGFBP5 correlated significantly with glioma histologic grade. 83% (58/70) of glioblastomas (WHO Grade IV) were positive for IGFBP5, which was significantly higher than WHO Grade III gliomas (41%, 41/101) or WHO Grade II gliomas (18%, 13/72) (p<0.001). In contrast, IGFBP3 was expressed in 17%, 23%, and 17% of WHO Grade IV, Grade III, and Grade II gliomas, respectively (p>0.05). There was no significant difference in IGFBP3 expression among different grades of glioma. Our study thus demonstrates that the expression of IGFBP5, but not IGFBP3, increases with glioma anaplastic progression. The strong correlation between overexpression of IGFBP5 and histologic grade suggests that, in addition to IGFBP2, IGFBP5 may also play a role in glioma progression.

Biomarkers, Tumor↗
PubMed2006

Androgen receptor and prostate apoptosis response factor-4 target the c-FLIP gene to determine survival and apoptosis in the prostate gland.

Androgen receptor (AR) is a ligand-activated transcription factor that mediates the action of androgens and is essential for the growth, function, and cell differentiation of the prostate gland. Here, we demonstrated that the prostate apoptosis response factor-4 (par-4) functions as a novel AR coactivator. Par-4 physically interacted with the DNA-binding domain of AR, enhanced AR interaction with DNA, and increased AR-dependent transcription. Par-4 enhanced the c-FLIP promoter activity and was recruited on to the c-FLIP gene in the presence of androgens, and the dominant-negative par-4 decreased c-FLIP expression. These results suggest that, in addition to its proapoptotic function, par-4 acts as a novel transcription cofactor for AR to target c-FLIP gene expression. In addition, we demonstrated that loss of c-FLIP expression was essential for castration-induced apoptosis in the prostate gland and that enhanced c-FLIP expression was associated with prostate cancer progression to the androgen-resistant stage. Our data shed light on a transcription-mediated mechanism for the effects of the AR pathway on cell survival and apoptosis.

Animals↗
PubMed2006

Polymorphisms in the glucokinase-associated, dual-specificity phosphatase 12 (DUSP12) gene under chromosome 1q21 linkage peak are associated with type 2 diabetes.

Linkage of type 2 diabetes to chromosome 1q21-q23 is well replicated across populations. In an initial 50-kb marker map (580 markers) across the linked region, one of the two strongest associations observed in Utah Caucasians was at marker rs1503814 (P < 0.00001 in pools, P < 0.004 in individuals). Based on this association, we typed additional markers and screened for sequence variation in the nearby DUSP12 gene. The strongest associations mapped to a highly conserved nongenic sequence just telomeric to rs1503814 and extended 10 kb telomeric through the DUSP12 gene and into the 5' end of the adjacent ATF6 gene. No coding variant could explain the association in the DUSP12 gene. An extended haplotype encompassing markers from -8,379 to +10,309 bp relative to the ATG start was more common in Caucasian case (0.381) than control subjects (0.285, P = 0.005) and was uniquely tagged by a 194-bp allele at either of two simple tandem repeat variants or by the T allele at marker +7,580. Markers -8,379 and +7,580 were nominally associated with type 2 diabetes in African-American subjects (P < 0.05), but with different alleles. Marker rs1503814 was strongly associated with postchallenge insulin levels among family members (P = 0.000002), but sequence variation in this region was not associated with type 2 diabetes in three other populations of European ancestry. Our data suggest that sequences in or upstream of DUSP12 may contribute to type 2 diabetes susceptibility, but the lack of replication suggests a small effect size.

Black People↗
PubMed2006

Human Streptococcus suis outbreak, Sichuan, China.

From mid-July to the end of August 2005, a total of 215 cases of human Streptococcus suis infections, 66 of which were laboratory confirmed, were reported in Sichuan, China. All infections occurred in backyard farmers who were directly exposed to infection during the slaughtering process of pigs that had died of unknown causes or been killed for food because they were ill. Sixty-one (28%) of the farmers had streptococcal toxic shock syndrome; 38 (62%) of them died. The other illnesses reported were sepsis (24%) and meningitis (48%) or both. All isolates tested positive for genes for tuf, species-specific 16S rRNA, cps2J, mrp, ef, and sly. A single strain of S. suis caused the outbreak, as shown by the identification of a single ribotype. The high death ratio was of concern; prohibiting backyard slaughtering ended the outbreak.

Adult↗
PubMed2006

Streptococcus suis sequence type 7 outbreak, Sichuan, China.

An outbreak of Streptococcus suis serotype 2 emerged in the summer of 2005 in Sichuan Province, and sporadic infections occurred in 4 additional provinces of China. In total, 99 S. suis strains were isolated and analyzed in this study: 88 isolates from human patients and 11 from diseased pigs. We defined 98 of 99 isolates as pulse type I by using pulsed-field gel electrophoresis analysis of SmaI-digested chromosomal DNA. Furthermore, multilocus sequence typing classified 97 of 98 members of the pulse type I in the same sequence type (ST), ST-7. Isolates of ST-7 were more toxic to peripheral blood mononuclear cells than ST-1 strains. S. suis ST-7, the causative agent, was a single-locus variant of ST-1 with increased virulence. These findings strongly suggest that ST-7 is an emerging, highly virulent S. suis clone that caused the largest S. suis outbreak ever described.

Animals↗
PubMed2006

[Effects of heat shock protein gp96 on function of macrophages from mouse].

BACKGROUND & OBJECTIVE: Heat shock protein gp96 (HSPgp96) plays an important role in antigen presenting and specific antitumor immunotherapy, but its effects on macrophages need further investigation. This study was to investigate the effects of HSPgp96 derived from H22 tumor cells on mouse peritoneal elicited macrophages (PEMphi) by detecting some factors that are related to the function of the macrophages. METHODS: After macrophages were stimulated by HSPgp96, dynamic changes of intracellular free calcium (Ca2+), nitric oxide (NO) and reactive oxygen species (ROS) in the macrophages were measured by the laser scanning confocal microscopy (LSCM) with sensitive fluorescent dye Fluo-3/AM, DAF-FM-DA, and H2DCF-DA. The color immunofluorescence assay was used to observe the expression intensity and distribution of MHC II and CD86 in the macrophages. RESULTS: The production of Ca2+, NO and ROS increased rapidly in the macrophages after stimulation of HSPgp96. Their concentration peaks appeared at 30 s, 80 s, and 580 s after stimulation with the increase scopes of (161.06+/-70.99)%, (77.58+/-31.17)%, and (647.28+/-185.70)%, respectively. The positive rates of MHC II and CD86 were significantly higher in 60 mg/L HSPgp96-stimulated macrophages than in control macrophages [(61.8+/-5.1)% vs. (40.9+/-3.5)%, P<0.01; (54.9+/-2.0)% vs.(23.1+/-3.1)%, P<0.01]. CONCLUSION: The in vitro stimulation of HSPgp96 may enhance the production of Ca2+, NO and ROS in mouse PEMphi, and up-regulate the expression of MHC II and CD86.

Animals↗
PubMed2006

[Individualized and comprehensive therapy for severe acute pancreatitis in early stage: analysis of 110 cases].

OBJECTIVE: To investigate the risk factors of exacerbation of severe acute pancreatitis (SAP) in early stage, in order to formulate therapeutic strategies including minimally invasive intervention and organ support, and to finalize an individualized and comprehensive therapy for the SAP in early stage to decrease the mortality. METHODS: Fifty-three patients with SAP admitted from 1995 to 1999 was categorized as group 1, and 57 patients admitted from 2000 to 2005 as group 2, were analyzed retrospectively. Ranson's score, acute physiological and chronic health evaluation II (APACHE II) score, Balthazar CT grade, presence or absence of biliary tract obstruction, hypoxia, lung infection, shock, abdomen compartment syndrome (ACS), hyperlipemia, pleural effusion were analysed logistically. Mortality following different treatments and incidence rate of complications were also evaluated. RESULTS: In the two groups, 13 patients of the group 1 and 14 of group 2 were complicated with multiple organ dysfunction syndrome (MODS) in the early stage. There was difference in Ranson's score, APACHE II, Balthazar CT grade, between the groups with and without MODS (all P<0.05). Higher incidences of shock, biliary tract obstruction, ACS, hyperlipemia, pleural effusion were seen in group with MODS (P<0.01). Mortality of group 2 patients was lowered after receiving a comprehensive therapy including bedside hemodialysis (CBP) and artificial liver support (P<0.01). CONCLUSION: Development of MODS in SAP and its mortality are related to strategies of treatment, and adoption of an individualized and comprehensive therapy for the SAP in early stage can decrease the complications and the mortality.

Acute Disease↗
PubMed2006

Genetically modified myeloma cell vaccine inducing antitumor immune response in vivo.

This study was aimed to evaluate the in vivo antitumor effect of genetically modified myeloma cell vaccine on human myeloma xenografts implanted into nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice. Human immune system was established in NOD/SCID mice by intraperitoneal injection of human peripheral blood lymphocytes (PBLs). After being inoculated subcutaneously with irradiated myeloma cell line sko-007, adenovirally transferred with GFP or p53, granulocyte-macrophage colony-stimulating factor (GM-CSF) and B7-1 genes, huPBL-NOD/SCID mice were challenged by subcutaneous injection of non-transferred sko-007 cells. The results indicated that Ad-p53/GM-CSF/B7-1-infected sko-007 cell vaccination significantly reduced local tumor growth compared with controls. Histopathological and immunohistochemical analysis showed that tumor tissues increasingly displayed diffuse necrosis, mainly caused by apoptosis, accompanied with significant fibroplasias and blood vessel hyperplasia, and human T cells infiltrated into the tumor tissues. It is concluded that transgenic p53, GM-CSF and B7-1 expression produces an immune response against myeloma cells and may be of therapeutic value for multiple myeloma in human being.

Adenoviridae↗
PubMed2006

[Study on manpower allocation criteria of center of disease prevention and control in the context of province level, city level and county level].

OBJECTIVE: To set the manpower allocation criteria of center of disease prevention and control. METHODS: Expected allocation manpower criteria was obtained through adjusting the current manpower allocation of disease prevention and control centers. The principle was to fulfill public function and promote professional efficiency. RESULTS: Based on function requirement, in 3 - 5 years, the manpower allocation criteria of center of disease prevention and control at provincial-level is 336 persons, at city-level is 102 persons, and at county-level is 33 persons, that means in whole country 140016 persons should be needed. In 10 years, the manpower allocation criteria of center of disease prevention and control at provincial-level is 386 persons, at city-level is 112 persons, and at county-level is 38 persons, that means in whole country 159086 persons should be needed. CONCLUSION: The manpower allocation criteria advanced in the study indicated that current manpower quantity should be greatly reduced. It is an inevitable trend that disease prevention and control centers reduce the staff quantity and promote their quality.

China↗
PubMed2006

[Mixed epithelial and stromal tumor of kidney].

OBJECTIVE: To study the clinicopathological features and differential diagnoses of mixed epithelial and stromal tumor of the kidney. METHODS: Clinical and pathological characteristics of 4 cases of mixed epithelial and stromal tumor of the kidney were studied. RESULTS: Three patients were female and one was male. All patients presented with flank pain and hematuria. Radiologic studies revealed cystic and solid masses involving the kidney. Grossly the tumors had a solid and cyst appearance. Microscopically, the tumors were composed of a mixture of stromal and epithelial elements. The epithelial elements were variable in cell types including cuboidal, hobnail and columnar cells. One case showed Müllerian and intestinal epithelial differentiations. Stromal elements essentially consisted of spindle cells, with thick-walled blood vessels and bands of smooth muscle cells as distinctive features of the tumor. Immunohistochemical staining revealed that the epithelial components were positive for AE1/AE3, whereas the stromal components were positive for ER, PR, and SMA. All patients underwent nephrectomy and were well without evidence of recurrence. CONCLUSIONS: Mixed epithelial and stromal tumor of the kidney is a benign neoplasm with distinct histopathological features. It should be distinguished from many other renal neoplasms. Surgical intervention is a preferred therapy.

Actins↗
PubMed2006

[Etiology of aseptic meningitis prevalent in Xuzhou].

BACKGROUND: To find the pathogenic agents of aseptic meningitis prevalent in Xuzhou of Jiangsu province in 2001. METHODS: The enterovirus (EV) was cultured from CSF of the patients and identified with anti-serum by neutralization test. Neutralization titer of antibody in paired sera from meningitis children was determined. EV RNA was detected by RT-PCR. RESULTS: Four strains of Coxsackievirus B5, 2 strains of Coxsackievirus B3 and 1 strain of Echovirus 7 were isolated from 22 CSF specimens. The isolation rate of virus was 31.8% (7/22), 21 CSF were tested by RT-PCR, the positive rate of EV RNA was 52.4% (11/21); 57.9% (11/19) of patients paired-sera had over 4 folds antibody rise or became seroconverted. CONCLUSION: Enterovirus was the pathogenic agent of aseptic meningitis prevalent in Xuzhou of Jiangsu province, the main serotype of the virus was Coxsackievirus B5.

Antibodies, Viral↗