Search PubMed⌕ Search

Biomedical subjects

Lei Kong

Publications and source records attributed to Lei Kong.

4 recordsLinked to original sources

NATsDB: Natural Antisense Transcripts DataBase.

Natural antisense transcripts (NATs) are reverse complementary at least in part to the sequences of other endogenous sense transcripts. Most NATs are transcribed from opposite strands of their sense partners. They regulate sense genes at multiple levels and are implicated in various diseases. Using an improved whole-genome computational pipeline, we identified abundant cis-encoded exon-overlapping sense-antisense (SA) gene pairs in human (7356), mouse (6806), fly (1554), and eight other eukaryotic species (total 6534). We developed NATsDB (Natural Antisense Transcripts DataBase, http://natsdb.cbi.pku.edu.cn/) to enable efficient browsing, searching and downloading of this currently most comprehensive collection of SA genes, grouped into six classes based on their overlapping patterns. NATsDB also includes non-exon-overlapping bidirectional (NOB) genes and non-bidirectional (NBD) genes. To facilitate the study of functions, regulations and possible pathological implications, NATsDB includes extensive information about gene structures, poly(A) signals and tails, phastCons conservation, homologues in other species, repeat elements, expressed sequence tag (EST) expression profiles and OMIM disease association. NATsDB supports interactive graphical display of the alignment of all supporting EST and mRNA transcripts of the SA and NOB genes to the genomic loci. It supports advanced search by species, gene name, sequence accession number, chromosome location, coding potential, OMIM association and sequence similarity.

Animals↗

Statistical inference of chromosomal homology based on gene colinearity and applications to Arabidopsis and rice.

BACKGROUND: The identification of chromosomal homology will shed light on such mysteries of genome evolution as DNA duplication, rearrangement and loss. Several approaches have been developed to detect chromosomal homology based on gene synteny or colinearity. However, the previously reported implementations lack statistical inferences which are essential to reveal actual homologies. RESULTS: In this study, we present a statistical approach to detect homologous chromosomal segments based on gene colinearity. We implement this approach in a software package ColinearScan to detect putative colinear regions using a dynamic programming algorithm. Statistical models are proposed to estimate proper parameter values and evaluate the significance of putative homologous regions. Statistical inference, high computational efficiency and flexibility of input data type are three key features of our approach. CONCLUSION: We apply ColinearScan to the Arabidopsis and rice genomes to detect duplicated regions within each species and homologous fragments between these two species. We find many more homologous chromosomal segments in the rice genome than previously reported. We also find many small colinear segments between rice and Arabidopsis genomes.

Algorithms↗

Clinical characteristics of acute pancreatitis patients with elevated serum triglyceride concentration.

OBJECTIVE: To evaluate the clinical characteristics of acute pancreatitis (AP) patients with elevated serum triglyceride (TG) concentration. METHODS: Ninety-nine cases of AP admitted from January 2000 to January 2002 were analyzed: 28 cases comprised the TG-elevated group (serum TG >1.7 mmol/L) and 71 cases were the TG-normal group (serum TG </=1.7 mmol/L). RESULTS: The AP patients with elevated serum TG accounted for 11.3% (9/80) of all AP cases during the study period. Pulmonary, cardiovascular and renal dysfunction within 72 h of onset of AP were all higher in the TG-elevated group than in the group with normal TG (25.0% vs 1.4%; 17.9% vs 1.4%; 14.3% vs 1.4%, respectively; P < 0.05). The incidence of pancreatic pseudocyst was 53.6% and 4.2%, respectively, in the group with elevated TG and in the group with normal TG (P < 0.05). CONCLUSIONS: Patients with AP and elevated serum TG concentration have organ dysfunction at an earlier stage and increased local complications. Non-surgical therapy was common for the majority of these patients.

Acute Disease↗

Clinical characteristics and prognostic factors of severe acute pancreatitis.

AIM: To investigate the clinical characteristics and prognostic factors of a consecutive series of patients with severe acute pancreatitis (SAP). METHODS: Clinical data of SAP patients admitted to our hospital from January 2003 to January 2004 were retrospectively reviewed. Collected data included the age, gender, etiology, length of hospitalization, APACHE II score at admission, local and organ/systemic complications of the patients. RESULTS: Of the 268 acute pancreatitis patients, 94 developed SAP. The mean age of SAP patients was 52 years, the commonest etiology was cholelithiasis (45.7%), the mean length of hospitalization was 70 d, the mean score of APACHE II was 7.7. Fifty-four percent of the patients developed necrosis, 25% abscess, 58% organ/systemic failure. A total of 23.4% (22/94) of the SAP patients died. Respiratory failure was the most common organ dysfunction (90.9%) in deceased SAP patients, followed by cardiovascular failure (86.4%), renal failure (50.0%). In the SAP patients, 90.9% (20/22) developed multiple organ/systemic failures. There were significant differences in age, length of hospitalization, APACHE II score and incidences of respiratory failure, renal failure, cardiovascular failure and hematological failure between deceased SAP patients and survived SAP patients. By multivariate logistic regression analysis, independent prognostic factors for mortality were respiratory failure, cardiovascular failure and renal failure. CONCLUSION: SAP patients are characterized by advanced age, high APACHE II score, organ failure and their death is mainly due to multiple organ/systemic failures. In patients with SAP, respiratory, cardiovascular and renal failures can predict the fatal outcome and more attention should be paid to their clinical evaluation.

APACHE↗