No abstract available.
Anus Neoplasms* ; DNA* ; Ploidies*

No abstract available.
Anus Neoplasms* ; DNA* ; Ploidies*

Molecules can enter the nucleus by passive diffusion or active transport mechanisms, depending on their size. Small molecules up to size of 50-60 kDa or less than 10 nm in diameter can diffuse passively through the nuclear pore complex (NPC), while most proteins are transported by energy driven transport mechanisms. Active transport of viral proteins is mediated by nuclear localization signals (NLS), which were first identified in Simian Virus 40 large T antigen and had subsequently been identified in a large number of viral proteins. Usually they contain short stretches of lysine or arginine residues. These signals are recognized by the importin super-family (importin α and β) proteins that mediate the transport across the nuclear envelope through Ran-GTP. In contrast, only one class of the leucine-rich nuclear export signal (NES) on viral proteins is known at present. Chromosome region maintenance 1 (CRM1) protein mediates nuclear export of hundreds of viral proteins through the recognition of the leucine-rich NES.

·AIM: Impairment of choroidal perfusion was found in AMD patients. We postulated that vasoactive agents,which can reduce choroidal blood flow resistance, might prevent the development of choroidal neovascularization (CNV). D-Timolol and L-Timolol are hypotensive agents used in cardiovascular and glaucoma therapy. Their effects on laser-induced experimental CNV rat model and human umbilical vein endothelial cells (HUVEC) were thus evaluated.·METHODS: Male Brown Norway rats were anesthetized to receive Nd:YAG laser to break the Bruch's membrane. D-Timolol and L-Timolol were given once daily through intraperitoneal injection after laser treatment for 4wk. Fluorescein angiography was performed on 2wk and 4wk. HUVEC were tested by proliferation assay and adhesion assay with D-Timolol and L-Timolol at different concentrations.· RESULTS: D-Timolol reduced the fluorescein leakage to 83% of the control group in laser-induced rat's CNV model at a dosage of 15mg/(kg·d). L-Timolol had no effect on CNV formation even at a higher dosage of 20mg/(kg·d). D-Timolol inhibited the endothelial cells proliferation significantly by 300mg/L. L-Timolol also significantly inhibited the cell proliferation at 1 000mg/L. But at a lower dose such as 300mg/L, no significant inhibitory effect was found. Both drugs showed no effect on cell adhesion function in cell culture experiments.· CONCLUSION: D-Timolol was found to prevent CNV development in laser-induced model in vivo and inhibit vascular endothelial cells proliferation in vitro. L-Timolol had no effect on cell proliferation at the same dose, and neither on rat CNV model. The results indicate these two isomers have different functions on rat's CNV prevention and on HUVEC cell proliferation.

Vertebrate genomes are characterized with CpG deficiency, particularly for GC-poor regions. The GC content-related CpG deficiency is probably caused by context-dependent deamination of methylated CpG sites. This hypothesis was examined in this study by comparing nucleotide frequencies at CpG flanking positions among invertebrate and vertebrate genomes. The finding is a transition of nucleotide preference of 5' T to 5' A at the invertebrate-vertebrate boundary, indicating that a large number of CpG sites with 5' Ts were depleted because of global DNA methylation developed in vertebrates. At genome level, we investigated CpG observed/expected (obs/exp) values in 500 bp fragments, and found that higher CpG obs/exp value is shown in GC-poor regions of invertebrate genomes (except sea urchin) but in GC-rich sequences of vertebrate genomes. We next compared GC content at CpG flanking positions with genomic average, showing that the GC content is lower than the average in invertebrate genomes, but higher than that in vertebrate genomes. These results indicate that although 5' T and 5' A are different in inducing deamination of methylated CpG sites, GC content is even more important in affecting the deamination rate. In all the tests, the results of sea urchin are similar to vertebrates perhaps due to its fractional DNA methylation. CpG deficiency is therefore suggested to be mainly a result of high mutation rates of methylated CpG sites in GC-poor regions.
AT Rich Sequence ; Animals ; CpG Islands ; genetics ; DNA Methylation ; GC Rich Sequence ; Gene Frequency ; Genome ; Genomics ; methods ; Humans ; Invertebrates ; genetics ; Isochores ; genetics ; Mutation ; Vertebrates ; genetics

BACKGROUNDLocal recurrence remains a serious problem among patients undergoing breast conservative surgery. This study aimed at identifying risk factors for residual disease after breast conservative surgery.

METHODSThis retrospective study was based on patients with invasive breast cancer who have received breast conservative surgery and subsequent completion mastectomy. All patients had a clear resection margin in the initial operation. We analyzed the association between the presence of residual disease during completion mastectomy and the following risk factors: T staging, young age, and presence of extensive intraductal component (EIC), a close margin, lymphovascular permeation (LVP), positivity of estrogen receptor, progesterone receptor, and c-erbB-2.

RESULTSResidual disease was encountered in 21 (45.7%) of 46 patients; EIC was present in 28 patients (60.9%), of whom 17 had residual disease. Presence of EIC during breast conservation surgery was associated with a higher risk of residual disease during completion mastectomy (P = 0.011). Other variables were not statistically significant risk factors for presence of residual disease. No local recurrence was recorded in our cohort, and the disease-free survival and overall survival after completion mastectomy were similar for patients who had residual disease and those who had not.

CONCLUSIONSThe presence of EIC is a significant risk factor for residual disease in patients after breast conservative surgery. Our findings may suggest the indicated value of completion mastectomy in patients with EIC during initial breast conservative surgery to decrease the risk of subsequent local failure.

Adult ; Age Factors ; Aged ; Aged, 80 and over ; Breast Neoplasms ; surgery ; Carcinoma, Intraductal, Noninfiltrating ; complications ; Disease-Free Survival ; Female ; Humans ; Mastectomy ; Mastectomy, Segmental ; Middle Aged ; Neoplasm, Residual ; pathology ; surgery ; Retrospective Studies ; Risk Factors

No abstract available.
Esophageal Achalasia

In the past decade, many countries in Asia, in particularly in East Asia, are experiencing a progressive rise in the incidence and prevalence of inflammatory bowel disease (IBD). Improved physician awareness and diagnostic methods are unlikely to fully account for this rapid increase. This epidemiological shift is likely to relate to industralization, westernization of lifestyles and changes in eating habits, as part of the socioeconomic development in Asia, although many of these putative environmental factors have not been formally investigated in Asian cohorts. Genetic factors for IBD differ between Asia and the West. NOD2/CARD15 mutation, repeatedly observed in the Caucasian populations, is not associated with Crohn's disease in Asian populations. Familial clustering is generally uncommon in Asia but it is expected to increase as the IBD prevalence in this region rises. Ethnic-racial differences of IBD have been described and Indians appear to be most affected in South-East Asia. Clinical manifestation of IBD in Asia resemble the Western population in general, but with some differences, including higher prevalence of males and ileocolonic disease, lower disease severity, surgical rates and extraintestinal manifestations. These differences may relate to time factor, genetic background and environmental factors. This review summarises recent epidemiological data of IBD including environmental factors associated with the development of IBD in Asia. Future research focusing on studying the epidemiology of IBD in an area of rapidly increasing prevalence such as Asia will allow the opportunity to identify potential risk factors and provide a better understanding of the aetiology of disease in the Asian population.
Asia ; Asian Continental Ancestry Group ; Cohort Studies ; Crohn Disease ; Eating ; Far East ; Humans ; Incidence ; Inflammatory Bowel Diseases ; Life Style ; Male ; Polymethacrylic Acids ; Prevalence ; Risk Factors ; Time Factors

In the past decade, many countries in Asia, in particularly in East Asia, are experiencing a progressive rise in the incidence and prevalence of inflammatory bowel disease (IBD). Improved physician awareness and diagnostic methods are unlikely to fully account for this rapid increase. This epidemiological shift is likely to relate to industralization, westernization of lifestyles and changes in eating habits, as part of the socioeconomic development in Asia, although many of these putative environmental factors have not been formally investigated in Asian cohorts. Genetic factors for IBD differ between Asia and the West. NOD2/CARD15 mutation, repeatedly observed in the Caucasian populations, is not associated with Crohn's disease in Asian populations. Familial clustering is generally uncommon in Asia but it is expected to increase as the IBD prevalence in this region rises. Ethnic-racial differences of IBD have been described and Indians appear to be most affected in South-East Asia. Clinical manifestation of IBD in Asia resemble the Western population in general, but with some differences, including higher prevalence of males and ileocolonic disease, lower disease severity, surgical rates and extraintestinal manifestations. These differences may relate to time factor, genetic background and environmental factors. This review summarises recent epidemiological data of IBD including environmental factors associated with the development of IBD in Asia. Future research focusing on studying the epidemiology of IBD in an area of rapidly increasing prevalence such as Asia will allow the opportunity to identify potential risk factors and provide a better understanding of the aetiology of disease in the Asian population.
Asia ; Asian Continental Ancestry Group ; Cohort Studies ; Crohn Disease ; Eating ; Far East ; Humans ; Incidence ; Inflammatory Bowel Diseases ; Life Style ; Male ; Polymethacrylic Acids ; Prevalence ; Risk Factors ; Time Factors

No abstract available.
Hearing Loss, Noise-Induced*