Biomedical subjects

Cheng Hu

Publications and source records attributed to Cheng Hu.

6 recordsLinked to original sources

PubMed2006

[Scanning the HNF4A gene mutation from Chinese pedigrees with early- and/or multiple-onset diabetes].

OBJECTIVE: To screen the mutation of hepatocyte nuclear factor 4 alpha gene (HNF4A) in Chinese pedigrees with early and/or multiplex-onset diabetes in Shanghai and nearby area. METHODS: By PCR-single strand conformation polymorphism (PCR-SSCP) and direct sequencing, the mutation screen of HNF4A gene was performed in 93 normal controls and 154 unrelated probands from early- and/or multiplex-onset diabetes. The PCR-RFLP was used to analyze the frequencies of the discovered mutations and variants. RESULTS: Two synonymous mutations (N153N, A158A) were found in two families, of which the N153N was co-segregated with early-onset diabetes. These two synonymous mutations were not detected in the 93 normal controls. Three variants, IVS1+308(A to G)(rs2071197), IVS1+357(A to T)(rs2071198), IVS1-5(C to T)(rs745975), were also identified in this study. The genotype and allele frequencies of the three variants had no difference between the probands and normal controls. CONCLUSION: HNF4A gene mutation is rare in Chinese pedigrees with early and/or multiplex-onset diabetes.

Adult↗

PubMed2005

[A novel mutation of WFS1 gene in Chinese patients with Wolfram syndrome].

OBJECTIVE: Wolfram syndrome is an autosomal recessive disorder characterized by early-onset diabetes mellitus, diabetes insipidus, optic atrophy and deafness. The aim of this study was to scan the WFS1 gene mutations in a Chinese Wolfram syndrome pedigree. METHODS: Eight exons and flanking introns of WFS1 gene were screened using PCR-DNA direct sequencing. Effects of the mutation on the structure and function of the WFS1 gene product, Wolframin, were evaluated by bioinformatics. RESULTS: A novel mutation, F417del, in the WFS1 gene was identified. The patient was homozygous of this mutation and the consanguineous parents were heterozygous. The mutation causes the lose of a non-polar amino acid, which was located in the transmembrane domain of the protein product. Bioinformatics predicted that the mutation altered the secondary structure of the transmembrane domain and decreased the hydrophobicity of F417del protein. CONCLUSIONS: This study identified a novel mutation of WFS1 gene and represented the first cause of molecular characterization of Chinese Wolfram syndrome patients.

Adult↗

PubMed2004

29Si and 27Al MAS NMR spectra of mullites from different kaolinites.

Mullites synthesized from four kaolinites with different random defect densities have been studied by 27Al and 29Si magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR) and X-ray diffraction (XRD). All these mullites show the same XRD pattern. However, 29Si and 27Al MAS NMR spectra reveal that the mullites derived from kaolinites with high defect densities, have a sillimanite-type Al/Si ordering scheme and are low in silica, whereas those mullites derived from kaolinites with low defect densities, consist of both sillimanite- and mullite-type Al/Si ordering schemes and are rich in silica.

Aluminum↗

PubMed2003

Effect of pH and temperature on the kinetics of odor oxidation using chlorine dioxide.

Increasing public concerns over odors and air regulations in nonattainment zones necessitate the remediation of a wide range of volatile organic compounds (VOCs) generated in the poultry-rendering industry. Currently, wet scrubbers using oxidizing chemicals such as chlorine dioxide (ClO2) are utilized to treat VOCs. However, little information is available on the kinetics of ClO2 reaction with rendering air pollutants, limiting wet scrubber design and optimization. Kinetic analysis indicated that ClO2 does not react with hexanal and 2-methylbutanal regardless of pH and temperature and implied that aldehyde removal occurs primarily via mass transfer. Contrary to the aldehydes, ethanethiol or ethyl mercaptan (a model compound for methanethiol or methyl mercaptan) and dimethyl disulfide (DMDS) rapidly reacted with ClO2. The overall reaction was found to be second and third order for ethanethiol and DMDS, respectively. Moreover, an increase in pH from 3.6 to 5.1 exponentially increased the reaction rate of ethanethiol (e.g., k2 = 25-4200 L/mol/sec from pH 3.6 to 5.1) and significantly increased the reaction rate of DMDS if increased to pH 9 (k3 = 1.4 x 10(6) L2/mol2/sec). Thus, a small increase in pH could significantly improve wet scrubber operations for removal of odor-causing compounds. However, an increase in pH did not improve aldehyde removal. The results explain why aldehyde removal efficiencies are much lower than methanethiol and DMDS in wet scrubbers using ClO2.

Abattoirs↗

PubMed2003

Effective normalization method for sample-position-dependence effect in photoacoustic spectrometry.

Sample position dependence effect in photoacoustic (PA) spectrometry has been reported by several scientists. This effect must be taken into account in a PA application that requires a quantitative theoretical treatment. In this work, we experimentally investigated PA signal magnitude varying with sample-to-window distance in an MTEC Model 300 Photoacoustic Detector, which has a fixed empty (gas) volume in addition to the sample-to-window-distance-dependent gas volume. An operative method was introduced to obtain the coefficient, which considered the sample-to-window distance and the additional gas volume. With this coefficient, the one-dimensional PA model, developed by Aamodt, Murphy, and Parker, can be employed to quantitatively process PA experimental data, no matter what the sample-to-window distance is. Quantitative measurements of thermal effusivities of two samples were performed to prove this effective normalization method.

Acoustics↗

PubMed2003

[Immunophenotyping of 106 adult patients with acute leukemia by flow cytometry].

OBJECTIVE: To study the immunophenotyping of adult patients with acute leukemia and its association with the prognosis. METHODS: Immunophenotyping was performed in 106 adult patients with acute leukemia by three-color flow cytometry analysis using CD34/SSC gating. RESULTS: The antigens expressed in 71 patients with acute myeloid leukemia (AML) were mainly CD13, CD33, HLA-DR, CD34 and CD117. Lymphoid antigen expression was identified in 23.9% adult AML patients and CD56 antigen expression in 15.5% of the AML patients. In 29 patients with acute lymphoblastic leukemia (ALL), the expressed antigens were mainly HLA-DR, CD10, CD19, CD34 and CD7, and 34.5% of these patients were found to be positive for myeloid antigen expression. Complete remission (CR) rate in AML patients with lymphoid antigen expression after chemotherapy was lower than that in AML patients without lymphoid antigen expression (52.9% vs 77.8%, P<0.05), and no significant impact was noted of myeloid antigen expression in ALL on the CR of the patients (70.0% vs 94.7%, P>0.05). The CR rate in AML with CD56 antigen expression was lower than that in AML without CD56 expression (36.4% vs 78.3%, P<0.025), and the CR rate in CD34+ AML was lower than that in CD34- AML (56.0% vs 80.4%, P<0.05). CONCLUSIONS: Gating of CD45/SSC can eliminate the interference of normal cells to render more reliable immunophenotyping results. The expressions of CD56+, CD34+, lymphoid antigen in adult AML patients, who have lower CR rate, often signify poor prognosis.

Adolescent↗