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X Cui

Publications and source records attributed to X Cui.

At least 163 records · Page 9Linked to original sources
PubMed1992

Whole genome amplification from a single cell: implications for genetic analysis.

We have developed an in vitro method for amplifying a large fraction of the DNA sequences present in a single haploid cell by repeated primer extensions using a mixture of 15-base random oligonucleotides. We studied 12 genetic loci and estimate that the probability of amplifying any sequence in the genome to a minimum of 30 copies is not less than 0.78 (95% confidence). Whole genome amplification beginning with a single cell, or other samples with very small amounts of DNA, has significant implications for multipoint mapping by sperm or oocyte typing and possibly for genetic disease diagnosis, forensics, and the analysis of ancient DNA samples.

Base Sequence↗
PubMed1992

Gene-centromere linkage mapping by PCR analysis of individual oocytes.

We describe a general method of determining the recombination fraction between a polymorphic locus and the centromere in any species where single oocytes can be obtained. After removal of the first polar body, each oocyte is analyzed by PCR. The frequency of oocytes heterozygous at the polymorphic locus is used to estimate the recombination fraction. We estimate a recombination fraction of 0.15 between the mouse major histocompatibility complex (H-2) and the centromere of chromosome 17.

Animals↗
PubMed1992

ming is expressed in neuroblast sublineages and regulates gene expression in the Drosophila central nervous system.

Cell diversity in the Drosophila central nervous system (CNS) is primarily generated by the invariant lineage of neural precursors called neuroblasts. We used an enhancer trap screen to identify the ming gene, which is transiently expressed in a subset of neuroblasts at reproducible points in their cell lineage (i.e. in neuroblast 'sublineages'), suggesting that neuroblast identity can be altered during its cell lineage. ming encodes a predicted zinc finger protein and loss of ming function results in precise alterations in CNS gene expression, defects in axonogenesis and embryonic lethality. We propose that ming controls cell fate within neuroblast cell lineages.

Amino Acid Sequence↗
PubMed1991

Genetic mapping by single sperm typing.

The polymerase chain reaction makes it possible to analyse DNA sequences in a single cell and has led to a new approach for constructing genetic maps. We describe a procedure called 'sperm typing' which can accurately classify individual meiotic products as recombinant of non-recombinant. This permits the linkage relationships among DNA polymorphisms to be determined without pedigree analysis.

Chromosome Mapping↗
PubMed1991

[Stimulated chemiluminescence and degranulation of human polymorphonuclear leukocytes: possible involvement in the mechanisms of tissue damage during inflammation].

A significant increase of polymorphonuclear leukocytes (PMN) chemiluminescence (CL) was observed when PMN was treated with rat C5ades Arg (r-C5ai), FMLP, opsozined zymosan (STZ) or a calcium ionophore A23487 separately. These stimuli, as well as aggregated IgG (A-IgG), could also cause the release of beta-glucuronidase (beta-g) and myeloperoxidase (MPO) from PMN, on the other hand, elastase (NE) release was not noticed when PMN was treated with r-C5ai and FMLP, which generally stimulated PMN in a cytochalasin B-dependent manner. These results suggest that the kinetics of PMN CL and degranulation vary depending upon the stimulus.

Calcimycin↗
PubMed1991

[The effect of Cu, Zn, Mn, on selenium content in the liver, brain, blood and kidney of mice].

The influence of dietary copper, zinc and manganese on the contents of selenium in liver, brain, and kidney of 150 mice was studied. The mice were divided into 5 groups with different trace elements in their forage (I. 40ppm Cu+4ppm Se, II. 100ppm Zn+4PPm Se, III. 4ppm Mn+4ppm Se, IV. control group). Every 10 mice were killed at one month intervals in each group and the contents of selenium in liver, brain, kidney and blood were determined. The selenium contents of blood, kidney in I, II groups were significantly lower than in IV group. The selenium content of liver was also significantly lower than IV group in two months, but no difference in the third month. No change of selenium content in brain had been observed.

Animals↗
PubMed1991

[Various methods of processing pyritum].

Five methods of processing pyritum and the effect of temperature fluctuations on processed products were studied using Fe2+ in the decoction, sulphur in processed products and sulphur separated out of processed products after adding hydrochloric acid as indexes. The results may serve as a reference for further study on pyritum.

Hot Temperature↗
PubMed1990

Direct electrophoretic detection of the allelic state of single DNA molecules in human sperm by using the polymerase chain reaction.

We have developed a procedure that allows the detection of polymerase chain reaction (PCR) products derived from a single target DNA molecule in a human sperm without using radioactive probes. With this method, three genetic loci present in a single sperm can be amplified simultaneously. The amplification procedure is specific as well as efficient and permits detection of the PCR product by ethidium bromide staining after polyacrylamide gel electrophoresis. When allele-specific PCR primers that differ in length are used, the size of the PCR products of different alleles also vary in length, allowing the allelic state at each locus to be determined electrophoretically. Studies on individual sperm by using this procedure should facilitate the measurement of genetic recombination in humans over small physical distances. The ability to directly analyze the allelic state of PCR products from one cell rapidly and simply will also be useful for the prenatal diagnosis of genetic disease, especially in the analysis of single blastomeres taken from in vitro fertilized eggs prior to implantation.

Alleles↗
PubMed1988

The Escherichia coli Ras-like protein (Era) has GTPase activity and is essential for cell growth.

The era gene of Escherichia coli encodes a protein (Era) which is similar to the eucaryotic RAS family of proteins. We report here that purified Era possesses both GTP-binding and GTPase activities. Era is also shown to be loosely associated with the inner membrane of E. coli. Overproduction of Era to 5% of the total cellular protein does not apparently alter either cell growth or cAMP levels. Disruption of the era gene by insertional inactivation is shown to be lethal by construction of a conditional lethal era mutant strain.

Bacterial Proteins↗
PubMedDate not supplied

Orally administered ginseng extract reduces serum total cholesterol and triglycerides that induce fatty liver in 66% hepatectomized rats.

The effects of ginseng extract (from the root of Panax ginseng) on factors inducing fatty liver were examined in 66% hepatectomized rats. Oral administration of ginseng extract at 125 or 250 mg/kg/day produced statistically significant reductions in total cholesterol and triglyceride concentrations in the blood 3 days after hepatectomy (P<0.05); the total cholesterol response appeared to be dose-related. Administration of ginseng extract at both doses also reduced total cholesterol and triglyceride concentrations in the liver 3 days after hepatectomy. Food intake and serum chemistry parameters indicating liver and kidney function were unchanged after ginseng administration except for the lipid metabolic parameters. These observations suggest that orally administered ginseng extract can suppress the formation of fatty liver after hepatic resection.

Administration, Oral↗
PubMedDate not supplied

Expression of p73 in colorectal carcinoma: clinicopathological relevance.

p73 gene expression and its correlation with clinicopathological variables were examined in 92 patients (53 male, 39 female; age range 38 - 89 years) with colorectal carcinoma. Gene expression was determined by immunohistochemical analysis of resected formalin-fixed and paraffin-embedded carcinoma specimens. When p73 staining of each specimen was divided into two modes (small expression, 0-50% and large expression, > 50%), small expression of p73 was obtained in most cases. Tumour, grade, stage, site and size did not correlate with the mode of expression, but tumour recurrence differed according to mode. Expression of p73 was also related to prognosis: large expression indicated a shorter survival period. Our findings suggest that p73 expression plays a role in inducing tumour recurrence, and that analysis of the expression is useful in evaluating the clinical course of colorectal carcinoma post-surgery.

Adult↗
PubMedDate not supplied

Increasing childhood trauma in Canada: findings from the National Population Health Survey, 1994/95.

Age-cohort variation in childhood trauma was examined in the present study. The data were taken from the 1994/95 Canadian National Population Health Survey of household residents (n = 15,106). Childhood trauma was measured by a seven-item index (items reflected physical abuse, fearful experiences, hospitalization, being sent away from home, and parental disturbance). Reported prevalence of childhood trauma increased with each successively younger age-cohort (range = 31% to 60%). Females showed a larger change than males, and age differences grew more pronounced as trauma exposure increased. The data suggest that childhood trauma has been on the increase over the last few decades. This is in accord with findings from other studies which showed that depression and social problems have also been on the rise. This suggests that adult psychiatric sequelae of early trauma can be expected to show an increase in future years.

Adolescent↗