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Jin Huang

Publications and source records attributed to Jin Huang.

At least 19 recordsLinked to original sources
PubMed2026

Deciphering the effects of sulfonamide antibiotics on denitrification from a metagenomic perspective: Inhibition of nitrite reduction and succession patterns of functional microorganisms.

Limited research has thoroughly elucidated the impact mechanisms of antibiotics on the denitrification process at the genomic and gene levels, which has hindered the optimization and development of nitrogen removal technology for antibiotic-containing swine wastewater. Lab-scale sequencing batch reactors were constructed in this study to treat synthetic wastewater containing different sulfonamides and nitrate. Investigations were carried out on denitrification performance, microbial community diversity, denitrifier succession patterns, and functional gene distribution. The stress of sulfonamides inhibited the nitrite reduction process, transforming complete denitrification into partial denitrification and causing significant nitrite accumulation. The average nitrogen removal efficiency in the treatment groups decreased from 81.0% ± 2.2-40.1% ± 6.1%. Alicycliphilus and Thauera were identified as the key taxa, accounting for 32.2% and 16.9% of all potential denitrifying bacteria, respectively. Although metagenome-assembled genomes (MAGs) from Thauera were enriched with genes encoding nitrate reductases (nap, nar) and nitrite reductases (nir), this genus preferentially utilized nitrate as an electron acceptor, resulting in the preferential nitrate reduction and subsequent nitrite accumulation. In contrast, Alicycliphilus MAGs developed tolerance to the sulfonamides stress during later stages, with concomitant enrichment of associated functional genes. They replaced Thauera to reemerge as the dominant group, thereby restoring complete denitrification. This study provides new insights into the regulatory mechanisms governing complete versus partial denitrification in nitrogen removal from antibiotic-containing wastewater.

Denitrifier succession↗
PubMed2006

Pseudolipasin A is a specific inhibitor for phospholipase A2 activity of Pseudomonas aeruginosa cytotoxin ExoU.

A number of bacterial pathogens utilize the type III secretion pathway to deliver effector proteins directly into the host cell cytoplasm. Certain strains of Pseudomonas aeruginosa associated with acute infections express a potent cytotoxin, exoenzyme U (ExoU), that is delivered via the type III secretion pathway directly into contacting host cells. Once inside the mammalian cell, ExoU rapidly lyses the intoxicated cells via its phospholipase A(2) (PLA(2)) activity. A high-throughput cell-based assay was developed to screen libraries of compounds for those capable of protecting cells against the cytotoxic effects of ExoU. A number of compounds were identified in this screen, including one group that blocks the intracellular activity of ExoU. In addition, these compounds specifically inhibited the PLA(2) activity of ExoU in vitro, whereas eukaryotic secreted PLA(2) and cytosolic PLA(2) were not inhibited. This novel inhibitor of ExoU-specific PLA(2) activity, named pseudolipasin A, may provide a new lead for virulence factor-based therapeutic design.

Animals↗
PubMed2006

Combination therapy with the single inhaler salmeterol/fluticasone propionate versus increased doses of inhaled corticosteroids in patients with asthma.

BACKGROUND: Although results from a few meta-analyses were most uniformly supportive of the beneficial effect of combination therapy on lung function, there were inconsistent results on other endpoints such as asthma exacerbation. Single inhalers of salmeterol and fluticasone propionate have been available, and some studies compared the effect of combination products with increased doses of inhaled corticosteroids (ICSs) on several outcome variables. OBJECTIVES: We reviewed the studies systematically, providing a quantitative summary estimate on the efficacy and safety measures of the combination products. METHODS: We searched databases (Medline and Embase) from January 1997 to December 2005 using 'fluticasone and salmerterol' or 'Seretide' or 'Advair', in combination with 'randomized controlled trial'. The databases of GlaxoSmithKline Clinical Trial Register and Cochrane Controlled Trials Register, or relevant articles were searched for additional studies. RESULTS: Combination products had a comparatively low, but significant improvement in pulmonary function, with morning peak expiratory flow (PEF), evening PEF and FEV1 increasing by 17.86 liters/min, 15.57 liters/min and 0.09 liter, respectively, compared with increased doses of inhaled corticosteroid (ICSs) over 12 weeks' treatment. But there were no statistically significant differences in other endpoints such as asthma exacerbation, overall withdrawal and drug-related adverse events, with the exception of overall adverse events and symptom free 24 h, which favored combination products. CONCLUSIONS: Thecombination products provided a statistically significant improvement in lung function and in symptoms but provided no significantly increased protection against exacerbation. Unless high doses of ICSs are required, there is insufficient evidence at present to recommend the use of combination products rather than increased moderate doses of ICSs as a first-line treatment for patients uncontrolled on their current doses of ICSs.

Administration, Inhalation↗
PubMed2006

Dynamic neuronal responses in cortical and thalamic areas during different phases of formalin test in rats.

Although formalin-induced activity in primary afferent fibers and spinal dorsal horn is well described, the forebrain neural basis underlying each phase of behavior in formalin test has not yet been clarified. The present study was designed to investigate the cortical and thalamic neuronal responses and interactions among forebrain areas during different phases after subcutaneous injection of formalin. Formalin-induced neuronal activities were simultaneously recorded from primary somatosensory cortex (SI), anterior cingulate cortex (ACC) and medial dorsal (MD) and ventral posterior (VP) thalamus during different phases (i.e., first phase, interphase, second phase and third recovery phase starting from 70 min after injection) of formalin test, using a multi-channel, single-unit recording technique. Our results showed that, (i) unlike the responses in primary afferent fibers and spinal dorsal horn, many forebrain neurons displayed monophasic excitatory responses in the first hour after formalin injection, except a small portion of neurons which exhibited biphasic responses; (ii) the response patterns of many cortical and thalamic neurons changed from excitatory to inhibitory at the end of the second phase; (iii) the direction of information flow also changed dramatically, i.e., from cortex to thalamus and from the medial to the lateral pathway in the first hour, but reversed in phase 3. These results indicate that the changes of activity pattern in forebrain networks may underlie the emerging and subsiding of central sensitization-induced pain behavior in the second phase of formalin test.

Action Potentials↗
PubMed2006

[Anatomical features of congenital chordee without hypospadias in children and implication for diagnosis and treatment].

OBJECTIVE: To investigate the anatomical features of congenital chordee without hypospadias in children and to discuss the diagnosis and treatment. METHODS: From August 1984 to December 2004, 94 children with chordee without hypospadias treated in the West China Hospital of Sichuan University were classified and analyzed for anatomical alterations. Their ages ranged from 18 months to 13 years (mean 6. 9 years). Ninety-four patients were divided into four groups. With intraoperation artificial erection, the patients with penis straightened after degloving were classified as type I patients (skin-tethering), those with penis straightened after fibrotic tissue in Buck's fascia released as type II patients (dysgenetic fascia), those with normal urethra and orthoplasty failed after degloving and removing fibrotic tissue as type III patients (corporal disproportion), and those with dysgenetic urethra tethering the corpora cavernosa as type lV patients (short urethra). RESULTS: In type I (n = 31, 32.9%) patients, the ventral skin and dartos fascia were contracted while Buck's fascia and the urethra was normal, in some (7 cases) scrotal skin extended to the ventral portion of penis (webbed penis). In type II (n = 45, 47.9%), contracture of Buck's fascia was evident and the thickening fibrotic tissue constituted the chief obstacle to orthoplasty, though in some skin was shortened. In type III (n = 6), the dorsal and ventral sides of the corpora cavernosa were disproportionated, and the morphologically normal urethra tightly adhered to the ventral aspect of corpora cavernosa. In some cases ventral skin and fascia were contracted, but orthoplasty could not be achieved through releasing these layers. In type IV (n = 12, 12.8%), the distal urethra was paper-thin and lacking corpus spongiosum, or dense fibrotic bands were found to be deep to the urethra. The urethra tethered the corpora cavernosa and formed a bow-to-string relation. The overlying skin and fascia were contracted in varying degrees while none had significance in straightening the penis. After operation, the length of penis increased to 6.9 cm from 5.2 cm on average and the chordee was corrected to 1.6 degrees from 42.6 degrees before operation on average. The patients were followed up 1 months to 15 years. The results were satisfactory. Chordee remained in 2 cases, fistula and urethral stricture occurred in 2 cases respectively, fistula in association with urethral stricture and diverticulum in 1 case; the operation was given again and the results was satisfactory. CONCLUSION: Patients with chordee without hypospadias may be divided into four types depending on which layer of the ventral penis constitutes the chief contribution to chordee. A systematic approach with repeated artificial erection tests is needed in determining the classification and surgical correction.

Adolescent↗
PubMed2006

[Treatment of female stress urinary incontinence with tension-free vaginal tape].

OBJECTIVE: To investigate the indication, approaches and prevention of complications in treatment of female stress urinary incontinence (SUI) with tension-free vaginal tape (TVT). METHODS: From September 2003 to December 2004, 40 cases of female stress urinary incontinence were treated, including 8 cases in association with cystocele or rectocele and 1 case in association with uterine prolapse. They ranged from 30 to 70 years in age with an average of 56.3 years. The disease course was 1-42 years (7.2 years on average). All patients received TVT. In the patients suffering from uterine prolapse and cystocele or rectocele, butterfly-shaped mesh patch was applied. RESULTS: All patients achieved satisfactory results. The complications included slight dysuria (2 cases), vesical perforation (1 case) and pelvic hematoma (1 case) and cleared up after treating. All cases were followed up 1 to 15 months and the results were satisfactory. No urinary incontinence and no dysuria reoccurred. CONCLUSION: TVT is effective for SUI.

Adult↗
PubMed2006

[Meta-analysis on NRAMP1 gene polymorphisms and tuberculosis susceptibility in East-Asia population].

OBJECTIVE: To provide a quantitative summary in estimating the association between polymorphisms of 3 loci in NRAMP1 gene and susceptibility to tuberculosis in East-Asia population by means of meta-analysis. METHODS: We searched databases (MEDLINE, OVID and CBM disc) from January 1995 to May 2005 using "NRAMP1" or "SLC11A1", in combination with "tuberculosis", also performed a manual search of citations from relevant original studies and literature. For each study involved, information was collected concerning the characteristics of the subjects, such as mean age of cases and the size of study. These characteristics were used to evaluate the sources of variation. Summary ORs and corresponding 95% CI were estimated by fixed effects (Mantel-Haenszel) or random effects (DerSimonian and Laird) model. To check for publication bias,a funnel plot, using Egger's linear regression method, was constructed. Cumulative meta-analysis was performed to evaluate whether the summary OR for studies with the polymorphisms of the 3 loci in the NRAMP1 gene was changing along with the accumulation of more data. Chi-square goodness of fit was used to test deviation from Hardy-Weinberg equilibrium. RESULTS: Eight publications, with the number of cases and controls of 1067 and 1084 respectively, were identified and all genotype frequencies were consistent with Hardy-Weinberg equilibrium. The summary ORs for studies with polymorphisms of 3' UTR, D543N and INT4 loci of the NRAMPI gene among the East-Asia population were 1.68(95% CI: 1.31-2.16, P< 0.001), 1.78(95% CI: 1.38-2.30, P< 0.001), 1.56 (95% CI: 0.72- 3.35, P = 0.26), respectively when compared with their corresponding common homozygotes. Publication bias was not found in the studies with the three loci, except for INT4 locus, by Egger linear regression method. The cumulative summary effects ORs were 1.85 (P = 0.02) in 2000, 1.35 (P = 0.12) in 2002,1.64 (P= 0.001) in 2003, and 1.68 (P<0.001) in 2004 for 3'UTR locus, 1.88 (P = 0.001) in 2000,1.65(P = 0.001) in 2002,1.70(P<0.001) in 2003,1.76(P<0.001) in 2004, and 1.78(P<0.001) in 2005 for D543N locus, and 0.88(P = 0:70) in 2002, 2.50(P = 0.41) in 2003, 1.52(P = 0.42) in 2004 and 1.56(P = 0.26) in 2005 for INT4 loucs. CONCLUSION: Polymorphisms at 3' UTR and D543N loci had statistically significant association between the NRAMP1 variants and susceptibility to tuberculosis in the East-Asia descendants, and variant in the INT4 locus failed to show statistically significant association in the East-Asia population.

Asian People↗
PubMed2006

[The value of using an AMACR/34betaE12/p63 cocktail double staining for diagnosis of prostate carcinoma and precarcinomatous lesions].

OBJECTIVE: To investigate the value of using an AMACR/34betaE12/p63 cocktail and double-staining for the diagnosis of small focal protatic carcinoma and precarcinomatous lesions. METHODS: A total of 130 consecutive cases were examined over a 3-month period, including 105 prostate needle biopsy samples, 6 radical prostatectomy specimens and 19 benign prostatic hyperplasia specimens which were excised transurethra or above pubis. 262 paraffin blocks of all the 1030 ones were stained with hematoxylin and eosin and by immunostains for AMACR, 34betaE12, p63, and an antibody cocktail comprising all the three with double-chromogen reaction. The diagnoses were then made according to the immunostaining, HE staining and clinical information. RESULTS: In the sections stained by the 3-antibody cocktail, blue-black cytoplasmic staining was observed in the epithelial cells of prostatic carcinoma and high-grade prostatic intraepithelial neoplasia (HGPIN) the basal cells of benign glands were stained red. There were no red basal cells around the blue-black glandular epithelium of carcinoma, but discontinuous or consecutive red basal cells were present around the blue-black glandular epithelium of HGPIN. Prostatic carcinoma was found in 214 paraffin blocks (82%), including 31 small focal carcinoma. HGPIN were observed in 64 paraffin blocks (24%), including focal HGPIN and small gland alveolus HGPIN. AAH was found in one block. No benign glands were simultaneously positive for AMACR and negative for basal cell markers. CONCLUSION: Inmmunohistochemistry studies using a 3-antibody cocktail and double staining can improve the detection rate of small focal prostatic carcinoma and HGPIN.

Biomarkers, Tumor↗
PubMed2005

Conformation-specific affinity purification of proteins using engineered binding proteins: application to the estrogen receptor.

Affinity chromatography coupled with an "affinity tag" has become a powerful and routine technology for the purification of recombinant proteins. However, such tag-based affinity chromatography usually cannot separate different conformational states (e.g., folded and misfolded) of a protein to be purified. Here, we describe a strategy to separate different conformations of a protein by using "tailor-made" affinity chromatography based on engineered binding proteins. Our method involves: (i) engineering of a binding protein specific to a particular conformation of the protein of interest, and (ii) production and immobilization of the binding protein to prepare conformation-specific affinity chromatography media. Using "monobodies," small antibody mimics based on the fibronectin type III domain, as the target-binding proteins, we demonstrated the effectiveness of our method by separating the active form of the estrogen receptor alpha ligand-binding domain (ERalpha-LBD) from a mixture of active and misfolded species and by discriminating two different conformations of ERalpha-LBD bound to different ligands. Our strategy should be generally applicable to the preparation of conformationally homogeneous protein samples.

Chromatography, Affinity↗
PubMed2005

A family of microporous materials formed by Sn(IV) phosphonate nanoparticles.

Reaction of Sn(IV) with phosphonic acids results in the formation of tin phosphonates with a spherical morphology arising from the aggregation of nanosized individual particles. Under high magnification, the spheres are shown to be porous with surface areas of 200-515 m2/g, depending on the type of phosphonic acid and the synthesis conditions used. The pores are largely micro in nature but also somewhat dependent on the type of phosphonic acid utilized in the preparation. Both aliphatic and aromatic organic phosphonates form these spherical aggregates. Functional groups, such as amino and carboxyl, may be introduced as part of the phosphonic acid or subsequently by further reaction, leading to a large family of naturally formed nanoparticles with accompanying microporosity.

Journal Article↗
PubMed2005

Screening the whole genome of a pathogen in vivo for individual protective antigens.

We report the results of a general protocol that was used to screen the whole genome of Chlamydophila abortus, type strain B577 (formerly Chlamydia psittaci strain B577), in a mouse pneumonia model. Genetic immunization was used to functionally test the genes of C. abortus as vaccines in a mouse challenge system. Nine gene fragments were isolated that conferred protection, with five protecting as effectively as the live-vaccine positive control. Bioinformatics approaches were unable to reconstruct isolation of these antigens. These results suggest that pathogen genomes can be functionally screened for vaccine candidate antigens in a mouse model to reveal new classes of vaccine candidate antigens that may have therapeutic efficacy across host species, disease manifestations, and delivery platforms.

Animals↗
PubMed2005

Two cloud-point phenomena in tetrabutylammonium perfluorooctanoate aqueous solutions: anomalous temperature-induced phase and structure transitions.

This paper reported the phase behavior and aggregate structure of tetrabutylammonium perfluorooctanoate (TBPFO), determined by differential scanning calorimeter, electrical conductivity, static/dynamic light scattering, and rheology methods. We found that above a certain concentration the TBPFO solution showed anomalous temperature-dependent phase behavior and structure transitions. Such an ionic surfactant solution exhibits two cloud points. When the temperature was increased, the solution turned from a homogeneous-phase to a liquid-liquid two-phase system, then to another homogeneous-phase, and finally to another liquid-liquid two-phase system. In the first homogeneous-phase region, the aggregates of TBPFO were rodlike micelles and the solution was Newtonian fluid. While in the second homogeneous-phase region, the aggregates of TBPFO were large wormlike micelles, and the solution behaved as pseudoplastic fluid that also exhibited viscoelastic behavior. We thought that the first cloud point might be caused by the "bridge" effect of the tetrabutylammonium counterion between the micelles and the second one by the formation of the micellar network.

Calorimetry, Differential Scanning↗
PubMed2005

Effect of lycium barbarum polysaccharide on human hepatoma QGY7703 cells: inhibition of proliferation and induction of apoptosis.

Lycium barbarum polysaccharide (LBP), extracted from Lycium barbarum that is a kind of traditional Chinese herb, is found to have anticancer activity. In this study, the effect of LBP on the proliferation rate, cell cycle distribution and apoptosis in the human hepatoma QGY7703 cell line were investigated. The effects of this compound were also tested on the concentration of calcium in cells. LBP treatment caused inhibition of QGY7703 cell growth with cycle arrest in S phase and apoptosis induction. The amount of RNA in cells and the concentration of intracellular Ca2+ were increased. Moreover, the distribution of calcium in cells was changed. Taken together, the study suggests that the induction of cell cycle arrest and the increase of intracellular calcium in apoptotic system may participate in the antiproliferative activity of LBP in QGY7703 cells.

Antineoplastic Agents, Phytogenic↗
PubMed2005

Low European methyl chloroform emissions inferred from long-term atmospheric measurements.

Methyl chloroform (CH3CCl3, 1,1,1,-trichloroethane) was used widely as a solvent before it was recognized to be an ozone-depleting substance and its phase-out was introduced under the Montreal Protocol. Subsequently, its atmospheric concentration has declined steadily and recent European methyl chloroform consumption and emissions were estimated to be less than 0.1 gigagrams per year. However, data from a short-term tropospheric measurement campaign (EXPORT) indicated that European methyl chloroform emissions could have been over 20 gigagrams in 2000 (ref. 6), almost doubling previously estimated global emissions. Such enhanced emissions would significantly affect results from the CH3CC13 method of deriving global abundances of hydroxyl radicals (OH) (refs 7-12)-the dominant reactive atmospheric chemical for removing trace gases related to air pollution, ozone depletion and the greenhouse effect. Here we use long-term, high-frequency data from Mace Head, Ireland and Jungfraujoch, Switzerland, to infer European methyl chloroform emissions. We find that European emission estimates declined from about 60 gigagrams per year in the mid-1990s to 0.3-1.4 and 1.9-3.4 gigagrams per year in 2000-03, based on Mace Head and Jungfraujoch data, respectively. Our European methyl chloroform emission estimates are therefore higher than calculated from consumption data, but are considerably lower than those derived from the EXPORT campaign in 2000 (ref. 6).

Atmosphere↗
PubMed2005

SCF(beta-TrCP1) controls Smad4 protein stability in pancreatic cancer cells.

Smad4, also known as deleted in pancreatic carcinoma locus 4 (DPC4), is a critical co-factor in signal transduction pathways activated by transforming growth factor (TGF)-beta-related ligands that regulate cell growth and differentiation. Mutations in Smad4/DPC4 have been identified in approximately 50% of pancreatic adenocarcinomas. Here we report that SCF(beta-TrCP1), a ubiquitin (E3) ligase, is a critical determinant for Smad4 protein degradation in pancreatic cancer cells. We found that F-box protein beta-TrCP1 in this E3 ligase interacted with Smad4 and that SCF(beta-TrCP1) inhibited TGF-beta biological activity in pancreatic cancer cells by decreasing Smad4 stability. Very low Smad4 protein levels in human pancreatic ductal adenocarcinoma cells were observed by immunohistochemistry. By analyzing pancreatic tumor-derived Smad4 mutants, we found that most point-mutated Smad4 proteins, except those within or very close to a mutation cluster region, exhibited higher interaction affinity with beta-TrCP1 and significantly elevated protein ubiquitination by SCF(beta-TrCP1). Furthermore, AsPC-1 and Caco-2, two cancer cell lines harboring Smad4 point mutations, exhibited rapid Smad4 protein degradation due to the effect of SCF(beta-TrCP1). Both Smad4 levels and TGF-beta signaling were elevated by retrovirus-delivered beta-TrCP1 siRNA in pancreatic cancer cells. Therefore, inhibition of Smad4-specific E3 ligase might be a target for therapeutic intervention in pancreatic cancer.

Adenocarcinoma↗