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Biomedical subjects

X Y Kong

Publications and source records attributed to X Y Kong.

13 recordsLinked to original sources

Microsatellite mapping of a Triticum urartu Tum. derived powdery mildew resistance gene transferred to common wheat (Triticum aestivum L.).

A powdery mildew resistance gene from Triticum urartu Tum. accession UR206 was successfully transferred into hexaploid wheat (Triticum aestivum L.) through crossing and backcrossing. The F1 plants, which had 28 chromosomes and an average of 5.32 bivalents and 17.36 univalents in meiotic pollen mother cells (PMC), were obtained through embryos rescued owing to shriveling of endosperm in hybrid seed of cross Chinese Spring (CS) x UR206. Hybrid seeds were produced through backcrossing F1 with common wheat parents. The derivative lines had normal chromosome numbers and powdery mildew resistance similar to the donor UR206, indicating that the powdery mildew resistance gene originating from T. urartu accession UR206 was successfully transferred and expressed in a hexaploid wheat background. Genetic analysis indicated that a single dominant gene controlled the powdery mildew resistance at the seedling stage. To map and tag the powdery mildew resistance gene, 143 F2 individuals derived from a cross UR206 x UR203 were used to construct a linkage map. The resistant gene was mapped on the chromosome 7AL based on the mapped microsatellite makers. The map spanned 52.1 cM and the order of these microsatellite loci agreed well with the established microsatellite map of chromosome arm 7AL. The resistance gene was flanked by the microsatellite loci Xwmc273 and Xpsp3003, with the genetic distances of 2.2 cM and 3.8 cM, respectively. On the basis of the origin and chromosomal location of the gene, it was temporarily designated PmU.

Ascomycota↗

Germline mutational analysis of CDH1 and pathologic features in familial cancer syndrome with diffuse gastric cancer/breast cancer proband in a Chinese family.

AIMS: Hereditary non-polyposis colorectal cancer, thyroid medullary carcinoma, breast/ovarian cancer and gastric cancer/breast cancer syndrome are encountered in surgery. Some gastric cancer/breast cancer syndrome may be the result of a CDH1 germline mutation. This is the first report of CDH1 germline mutations gastric cancer/breast cancer syndrome in Chinese patients. METHODS: Peripheral blood from the proband, as well as, her first and second degree relatives was collected and CDH1 gene exon 1-16 mutations were screened. E-cadherin/beta-catenin proteins expression and histopathologic features were examined on gastric cancer/breast cancer tissues from the proband. RESULTS: A C-->T nucleotide substitution at exon 13 (mRNA 2200 locus, Accession number NM-004360) was found. This was a transition from GCC-->GCT in DNA sequence (Ala154Ala). Diffuse-type gastric cancer and infiltrating ductal breast carcinoma were present. Both tumours preserved E-cadherin/beta-catenin expression immunohistochemically. CONCLUSIONS: Familial cancer syndrome with diffuse-type gastric cancer/breast cancer proband in Chinese has a propensity of early onset during lifespan. No truncating or splice-site CDH1 mutations had been identified in this family. A silent nucleotide variation in exon 13 of the CDH1 gene may contribute to some forms of cancer susceptibility.

Adult↗

Induced growth of asymmetric nanocantilever arrays on polar surfaces.

We report that the Zn-terminated ZnO (0001) polar surface is chemically active and the oxygen-terminated (000(-)1) polar surface is inert in the growth of nanocantilever arrays. Longer and wider "comblike" nanocantilever arrays are grown from the (0001)-Zn surface, which is suggested to be a self-catalyzed process due to the enrichment of Zn at the growth front. The chemically inactive (0001;)-O surface typically does not initiate any growth, but controlling experimental conditions could lead to the growth of shorter and narrower nanocantilevers from the intersections between (000(-)1)-O with +/- (01(-)10) surfaces.

Journal Article↗

Identification of a locus for porokeratosis palmaris et plantaris disseminata to a 6.9-cM region at chromosome 12q24.1-24.2.

BACKGROUND: Porokeratosis palmaris et plantaris disseminata (PPPD) is a rare autosomal dominant dyskeratotic disorder characterized by a cornoid lamella with parakeratosis, hyperkeratosis and loss of granular layers. The genetic basis of this disease is still unknown. Two loci for disseminated superficial actinic porokeratosis (DSAP) were found to be located on 12q23.2-24.1 and 15q25.1-26.1. Both PPPD and DSAP are disseminated types of porokeratosis. OBJECTIVES: To locate the locus for PPPD, thereby facilitating the identification of this disease gene and leading to an understanding of the pathogenesis of porokeratosis. METHODS: Genotyping was performed in a Chinese family with PPPD using polymorphic microsatellite markers on 12q and 15q. RESULTS: The locus for PPPD is located within a 6.9-cM region between markers D12S1613 and D12S1341, with a maximum two-point LOD score of 8.14 (theta = 0.00) at D12S1335. CONCLUSIONS: This study provides a map location for isolation of a gene causing PPPD.

Adolescent↗

[New progress of serial analysis of gene expression].

As an efficient tool that has been developed recently, serial analysis of gene expression (SAGE) allows the qualitative and quantitative analysis of a large number of transcripts. It can define the transcripts at relatively low levels and characterize the genomic expression near completion. In addition, it provides insights into the timely and orderly expression of genes by comparing the profiles constructed for a pair of cells that are kept at different conditions, thus identifying a set of novel genes. In this review, the newest progress of SAGE's application and research is mentioned in details with its original method and principle outlined.

Animals↗

[Influence of lead on activity of nitric oxide synthase in neurons and vessel smooth muscle of small intestine in rats].

The beta-NADPH histochemical method was used to study the effect of lead on activity of nitric oxide synthase(NOS) in neurons and vessel smooth muscles of intestinal wall in rats. The results showed that the number of NOS positive neurons and fibers was decreased and degenerative changes of some NOS positive neurons were found after the lead acetate intraperitoneal injection. The activity of NOS in the vessel smooth muscles was reduced. It suggests that lead colic may be induced by reduction of NO in the neurons which innervate the gut smooth muscles.

Animals↗

Effect of monocular enucleation or impulse blockage on gamma-aminobutyric acid and cytochrome oxidase levels in neurons of the adult cat lateral geniculate nucleus.

Much attention has been paid to the effect of various types of neonatally induced retinal insults on neurons of the cat lateral geniculate nucleus (LGN). Little is known about cellular adjustment to functional alterations commencing in the adult. The present study was aimed at examining the effect of monocular enucleation or retinal impulse blockade on mature neurons of the cat LGN and perigeniculate nucleus. In addition to labeling the relay neurons with cytochrome oxidase (CO) histochemistry and immunohistochemistry, and presumed interneurons with GABA immunohistochemistry, the two markers were also combined in the same section. The results showed that GABA-immunoreactive neurons in the LGN can be subdivided into two major groups: highly immunoreactive neurons (Hir) and moderately immunoreactive neurons (Mir). These two groups differed slightly in their size and CO levels. With monocular enucleation or TTX treatment, there was a reduction in the numerical density of Hir and a concomitant increase in Mir in the affected laminae. However, there was no evidence of a reduction in GABA immunoreactivity in neurons of the perigeniculate nucleus. With regard to relay cells our data were in agreement with our previous findings (Kageyama & Wong-Riley, 1985) that there was a statistically significant positive correlation between cell size and CO levels, so that neurons with large cross-sectional areas were predominately darkly reactive for CO (DCO), while medium-to-small neurons were mainly moderate to lightly reactive (M/LCO). After monocular enucleation or TTX injections, the numerical density and size of DCO were significantly reduced, while those of M/LCO were proportionally increased in the affected laminae, indicating a conversion of some DCO to M/LCO. The results indicate that the maintenance of CO levels in predominately the large relay cells and GABA levels in a subclass of small neurons of the mature cat LGN are activity-dependent and are highly sensitive to retinal insults.

Animals↗