Biomedical subjects

Hui Cheng

Publications and source records attributed to Hui Cheng.

22 records · Page 2Linked to original sources

PubMed2003

Analysis of comparative genomic hybridization and loss of heterozygosity in 43 primary gastric carcinomas.

OBJECTIVE: To investigate common chromosomal changes and the LOH frequency of microsatellite loci in primary gastric cancer samples in order to locate the deleted regions in which human gastric cancer related genes might exist. METHODS: Comparative genomic hybridization (CGH) was used to define global chromosomal aberrations in 43 primary gastric tumors. Based on the results of CGH, analysis of loss of heterozygosity (LOH) was performed in chromosome 19 in which the loss was first discovered in the gastric cancers. The PCR-based approach was used to investigate 22 loci, which are spaced at 1.1 - 10.9 cM intervals throughout chromosome 19. The amplified PCR fragments were subjected to electrophoresis in PAGE gel and analyzed with Genescan trade mark and Genotyper trade mark. RESULTS: CGH analysis revealed gains in chromosome 3p (8/43), 8q (8/43), 20 [20 (9/43), 20p (7/43), 20q (4/43)], 12q (16/43), 13q (12/43) and losses in 19 [19 (15/43)], 7 [17 (8/43), 17p (10/43)], 16 (10/43) and 1p (11/43). Among the 43 evaluated samples, the most frequent LOH was detected at locus D19S571 (27.81%). CONCLUSIONS: The tumorigenesis of gastric cancer includes several chromosomal changes. The aberration of chromosome 19 was the first common change founded in gastric cancer. The region near the D19S571 might harbor potential genes related to the tumorigenesis of gastric cancer.

Chromosomes, Human, Pair 19↗

PubMed2003

[Comparison of severe acute respiratory syndrome with community-acquired pneumonia].

OBJECTIVE: To study the features of severe acute respiratory syndrome (SARS) and community acquired pneumonia (CAP). METHODS: The clinical presentation, chest radiographs, white blood cell count and outcome of 45 SARS patients from April 5 to 20 2003 were compared, with those of 80 CAP patients from October 1 2002 to April 1 2003 in our hospital, and the clinical features of SARS were summarized. RESULTS: (1) Fever above 38.5 centigrade, dry cough, short of breath, headache, myalgia, diarrhea in SARS were more common in SARS patients than those in CAP (P<0.01). (2) Leucopenia was more common and leukocytosis was less common in SARS than those in CAP (P<0.01). (3) 22.2 percent of SARS patients were found abnormal chest radiographs within 24 hours after onset, 71.1 percent of SARS patients were showed progressive pulmonary infiltration via serial chest radiographs, while all CAP patients had abnormal chest radiographs when they were seen first time, and no patient showed progressive pulmonary infiltration, the difference was significant between the two groups (P<0.01). (4) Patients with SARS were lack of a response to the initial antimicrobial therapy, all patients with CAP had an adequate clinical response within three days, the difference was significant between the two groups(P<0.01 ). (5) The ratio of severe pneumonia and mortality in SARS was much higher than in CAP (both P<0.01). CONCLUSION: The clinical presentation, chest radiographs, white blood cell count, response to initial antimicrobial therapy, and outcome in SARS is much different from CAP, differentiate them will be helpful to early recognition, prompt isolation, and prevention of its spread.

Community-Acquired Infections↗

PubMed2003

Identification of alternate splice variants for murine SmX5.

We report here the identification of three additional murine SmX5 alternative transcripts, designated SmX5a, b and c. The cDNA of SmX5a possesses intron 1 in its entirety, and SmX5b harbors a part of intron 2. The retained fragment of SmX5c starts at the same position as SmX5b, but the retention extends through the remaining portion of intron 2. The sequence of retained DNA at all the intron-exon boundaries conforms to the "GT-AG" rule. RT-PCR analysis indicates that the three isoforms are stable transcripts, all at low frequency when compared with SmX5. Expression analysis by RT-PCR indicates that SmX5 and its isoforms exist in murine brain, kidney, testis, thymus, liver, spleen and heart. The SmX5a isoform is predominantly expressed in the thymus, while SmX5b and c are expressed in all tissues examined. The presence of alternatively spliced SmX5 isoforms and tissue-specific variation in splicing patterns suggests that SmX5 expression is complex and that the regulation of all four SmX5 mRNA levels may be critical in maintaining proper pre-mRNA splicing machinery in different cell types.

Alternative Splicing↗

PubMed2002

Gibberellin regulates Arabidopsis seed germination via RGL2, a GAI/RGA-like gene whose expression is up-regulated following imbibition.

The germination of Arabidopsis seeds is promoted by gibberellin (GA). Arabidopsis GAI, and RGA are genes encoding key GA signal-transduction components (GAI and RGA) that mediate GA regulation of stem elongation. The Arabidopsis genome contains two further genes, RGL1 and RGL2, that encode proteins (RGL1 and RGL2) that are closely related to GAI and RGA. Here, we show that RGL2 regulates seed germination in response to GA, and that RGL1, GAI, and RGA do not. In addition, we show that RGL2 transcript levels rise rapidly following seed imbibition, and then decline rapidly as germination proceeds. In situ GUS staining revealed that RGL2 expression in imbibed seeds is restricted to elongating regions of pre-emergent and recently emerged radicles. These observations indicate that RGL2 is a negative regulator of GA responses that acts specifically to control seed germination rather than stem elongation. Furthermore, as RGL2 expression is imbibition inducible, RGL2 may function as an integrator of environmental and endogenous cues to control seed germination.

Amino Acid Sequence↗