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1.
<正>INTRODUCTION Anthostomella rostrispora W.H. Hsieh, C.Y. Chen & Sivan. [as rostrospora] was described by Hsieh et al. (1975) and was accepted in the world monograph of the genus Anthostomella Sacc. 相似文献
2.
对云南产复叶耳蕨属植物进行了再次的分类订正研究,确认云南有该属植物20个种类,其中,华南复叶耳蕨Arachniodes festina(Hance)Ching和齿头复叶耳蕨A.aristata(Forst.)Tindale为云南分布新记录;将《中国植物志》等资料中的Acrorumohra dissecta、Arachniodes ailaoshanensis、A.australis、A.austro-yunnanensis、A.caudata、A.chinensis var.cornopteris、A.chinensis var.jinpingensis、A.chingii、A.dayaoensis、A.futeshanensis、A.gongshanensis、A.guangtongensis、A.lushuiensissis、A.pianmaensis,A.pianmaensis、A.pseudo-aristata、A.ppseudo-assamica、A.sshuangbaiensis、A.sinoaristata、A.sporadosora和A.triangularis等20个名称作为新异名处理。还列出了云南产该属植物的分种检索表、名称的处理及分类讨论、地理分布等。 相似文献
3.
We quantified HFE genotype frequencies in specimens submitted by physicians grouped by specialty and determined associations of genotypes with initial diagnosis based on phenotyping in patients evaluated at an iron disorders center. Of 526 specimens (519 from Alabama), these "typical" hemochromatosis-associated genotypes were detected: 85 C282Y/C282Y, 50 C282Y/H63D, and 27 H63D/H63D. Respective frequencies of C282Y/C282Y in specimens from an iron disorders center (n = 156), gastroenterologists (n = 147), hematologists/medical oncologists (n = 85), liver transplant surgeons (n = 11), endocrinologists and rheumatologists (n = 9), and "other sources" (n = 7) were greater (p < 0.05) than in population controls. In 44 patients from an iron disorders center initially diagnosed as "presumed hemochromatosis," 27 (61.4%) had C282Y/C282Y, 10 (22.7%) had C282Y/H63D, and 3 (6.8%) had H63D/H63D. C282Y/C282Y was not detected in 48 patients with "abnormality probably not an iron overload disorder." A total of 20.5% of 44 family members of patients had "typical" hemochromatosis-associated HFE genotypes (7.0% controls; p = 0.02). We conclude that most physicians who submitted specimens identify patients by phenotyping who have greater frequencies of "typical" hemochromatosis-associated HFE genotypes than controls, and that HFE mutation testing is useful in detecting hemochromatosis in family members of persons with hemochromatosis or iron overload. 相似文献
4.
The far ultraviolet circular dichroism spectra of sheep beta-lipotropic hormone (beta-LPH) were recorded under different conditions of pH, temperature, salt concentration, and solvent composition. Results confirm the stability of the hormone in strong basic or acidic solutions; moreover, temperatures up to 50 degrees C do not seem to affect noticeably the conformation of beta-LPH. However, increasing the NaC1 concentration or addition of dioxane in the solution brings about a conformational transition of the chain, interpreted as an increase in the helical content. The method of Yang (Chen, Y.H., Yang, J. T. & Martinez, H. M. (1972) Biochemistry 11, 4120-4131) was used to compute the proportion of helical, beta, and unordered forms of the hormone chain. The proportions are compared with those obtained from Fasman's predictive method (Chou, P. Y & Fasman, G. D. (1974) Biochemistry 13, 211-221 and Chou, P. Y. & Fasman, G. D. (1974) Biochemistry 13, 222-245) based on the known amino acid sequence of beta-LPH. 相似文献
5.
Hereditary hemochromatosis (HH) is an autosomal recessive disease caused by a defective iron absorption. C282Y is the most frequent HFE gene mutation causing HH in Northern European populations and their descendants. However, two other mutations, H63D and S65C, have been described as pathogenic changes. In this study, we have tried to evaluate the frequency of these three mutations in our community. Eighty-three patients with clinical and/or biochemical features of hemochromatosis and 150 controls were screened for H63D, S65C, and C282Y mutations using a PCR-restriction fragment length polymorphism (RFLP)-based strategy. In contrast to previous studies, 7% of the patients were homozygous for C282Y mutation. The remaining patients were 20% H63D homozygous, 10% H63D/C282Y compound heterozygous, 1% H63D/S65C compound heterozygous, 22% H63D heterozygous, 2% C282Y heterozygous, 2% S65C heterozygous, and 36% of patients lacked any of the three mutations studied, despite the fact that they showed clinical/biochemical features of hemochromatosis. We observed a high frequency of the H63D mutation in both the control group and patients, whereas the main genotypes implicated in HH in our series were H63D homozygous and H63D/C282Y compound heterozygous. We propose that the H63D mutation be analyzed in HH patients from our geographic area. Moreover, further studies are needed to elucidate the role of this mutation in the development of HH and the genetic, environmental or other factors that affect the genotype-phenotype correlation between H63D and hemochromatosis. 相似文献
6.
Kondrashova TV Neriishi K Ban S Ivanova TI Krikunova LI Shentereva NI Smirnova IA Zharikova IA Konova MV Taira S Tsyb AF 《Biochimica et biophysica acta》2006,1762(1):59-65
Possible association between the C282Y and H63D mutations in the HFE gene and estrogen-dependent cancer risk was assessed. Genotyping was performed using PCR amplification followed by digestion of products with specific restrictases. In a population of 260 healthy women (permanent residents of the southwest European Russia), mutant allele frequencies at the C282Y and H63D sites were evaluated as 3.3 and 16.3%, respectively. In patients with breast, ovarian, and endometrial cancer, C282Y frequencies were also low (1.0, 1.3, and 3.8%, respectively), and no cancer risk associated with the C282Y mutation was found. Odds ratios for breast cancer risk associated with the H63D mutation increased significantly with age: 0.5 in women below 48 years old, 1.0 in a range of 48-57 years, and 4.4 in older women (P(trend)=0.002). The latter value was statistically significant (95% CI, 1.4-14.1), indicating that women bearing the H63D mutation may be at an increased breast cancer risk at an age above 57 years. Preliminary results obtained in patients with two other estrogen-dependent malignancies revealed the same tendency to OR increase with age in ovarian cancer patients (P(trend)=0.008), but no age-related OR differences in endometrial cancer patients. 相似文献
7.
Genetic epidemiology studies of hereditary hemochromatosis (HHC) have shown a high prevalence of the C282Y mutation in individuals of the North Western European origin, whereas lower prevalence of HFE gene mutations was detected in the populations from southern European countries. However, no HFE mutation prevalence data have been provided for the population of Bosnia-Herzegovina so far. Therefore, the aim of this study was to determine the frequency of the C282Y and H63D HFE gene mutations in the population of Bosnia-Herzegovina. Among 200 analysed subjects 8 (4%) were C282Y heterozygotes; no C282Y homozygotes were found. The frequency of the H63D allele was 11.5%. There were 33 (16.5%) heterozygotes and 6 (3%) homozygotes for the H63D mutation. One (0.5%) compound heterozygote C282Y/H63D was identified. The observed C282Y and H63D allele frequency was 2.25% (95% confidence interval: 1.2-4.2) and 11.5% (95% confidence interval: 8.7-14.9), respectively. The prevalence of the C282Y and H63D mutations was estimated in Bosnia-Herzegovina, which fit well in the European northwest-to-southeast gradient of the C282Y mutation distribution. In addition, these results have an important implication for clinical evaluation of HHC in Bosnia-Herzegovina. 相似文献
8.
Species of Cephalostachyum Munro (Poaceae: Bambusoideae) from China are distributed in Yunnan and Tibet, mainly in Yunnan. In this paper, we discussed species of Cephalostachyum and compiled a key to species from China, based on recent studies on micromorphological characters of leaf epidermis and molecular phylogenetics of paleotropical woody bamboos. There is a total of seven species of Cephalostachyum distributed in China, all in Yunnan: Cchinense (Rendle) DZ. Li et HQ. Yang, Cfuchsianum Gamble et Hook. f., Cmannii (Gamble) Stapleton et DZ. Li, Cpallidum Munro, Cpingbianense (Hsueh et YM. Yang ex Yi et al.) DZ. Li et HQ. Yang, Csanguineum (WP. Zhang) DZ. Li et HQ. Yang and Cscandens Bor. Leptocanna Chia et HL. Fung and Cvirulentum YM Yang et F. Du are synonyms of Cephalostachyum Munro and Cfuchsianum Gamble et Hook. f. respectively. On the other hand, Cpergracile Munro and Cvirgatum (Munro) Kurz are morphologically closer to Schizostachyum Nees than to Cephalostachyum, and they should be treated as members of Schizostachyum. This paper is of significance to a worldwide revision of Cephalostachyum. 相似文献
9.
Baiotto C Sperb F Matte U da Silva CD Sano R Coelho JC Giugliani R 《Genetics and molecular biology》2011,34(1):45-48
Infantile GM1 gangliosidosis is caused by the absence or reduction of lysosomal beta-galactosidase activity. Studies conducted in Brazil have indicated that it is one of the most frequent lysosomal storage disorders in the southern part of the country. To assess the incidence of this disorder, 390 blood donors were tested for the presence of two common mutations (1622-1627insG and R59H) in the GLB1 gene. Another group, consisting of 26 GM1 patients, and the blood donors were tested for the presence of two polymorphisms (R521C and S532G), in an attempt to elucidate whether there is a founder effect. The frequencies of the R59H and 1622-1627insG mutations among the GM1 patients studied were 19.2% and 38.5%, respectively. The frequency of polymorphism S532G was 16.7%, whereas R521C was not found in the patients. The overall frequency of either R59H or 1622-1627insG was 57.7% of the disease-causing alleles. This epidemiological study suggested a carrier frequency of 1:58. Seven different haplotypes were found. The 1622-1627insG mutation was not found to be linked to any polymorphism, whereas linkage disequilibrium was found for haplotype 2 (R59H, S532G) (p < 0.001). These data confirm the high incidence of GM1 gangliosidosis and the high frequency of two common mutations in southern Brazil. 相似文献
10.
对云南产复叶耳蕨属植物进行了再次的分类订正研究,确认云南有该属植物20个种类,其中,华南复叶耳蕨Arachniodesfestina(Hance)Ching和齿头复叶耳蕨A.aristata(Forst.)Tindale为云南分布新记录;将《中国植物志》等资料中的Acrorumohradissecta、Arachniodesailaoshanensis、A.australis、A.austro-yunnanensis、A.caudata、A.chinensisvar.cornopteris、A.chinensisvar.jinpingensis、A.chingii、A.dayaoensis、A.futeshanen-sis、A.gongshanensis、A.guangtongensis、A.lushuiensis、A.pianmaensis、A.pseudo-aristata、A.pseudo-assa-mica、A.shuangbaiensis、A.sinoaristata、A.sporadosora和A.triangularis等20个名称作为新异名处理。还列出了云南产该属植物的分种检索表、名称的处理及分类讨论、地理分布等。 相似文献
11.
Cardoso CS Araújo HC Cruz E Afonso A Mascarenhas C Almeida S Moutinho J Lopes C Medeiros R 《Biochemical and biophysical research communications》2006,341(1):232-238
The present study examines the frequency of the two main HFE mutations (C282Y and H63D) in a randomly selected population of 346 individuals including 201 DNA samples from women with cervical neoplasia (including high-grade squamous intraepithelial lesions and invasive squamous cell carcinoma) and a control population of 146 women from the same geographical area. We found a significantly lower risk of development of cervical neoplasia in H63D carriers (OR = 0.56; 95% CI 0.35-0.92; p = 0.01). Multivariate logistic regression analysis confirms this observation (OR = 0.55; 95% CI 0.35-0.88, p = 0.01). Regarding the C282Y mutation no association was found (OR = 1.32; 95% CI 0.53-3.33; p = 0.52). In addition, a significant difference between H63D carrier and non-carrier women on the time-to-onset of cervical lesions was observed (log-rank test: p = 0.0012). These results indicate that HFE could be considered a candidate modifier gene of viral-related neoplasia such as cervical carcinoma possibly by a dual role on iron metabolism and immunological system. 相似文献
12.
Altes A Ruiz A Barceló MJ Remacha AF Puig T Maya AJ Castell C Amate JM Saz Z Baiget M 《Genetic testing》2004,8(4):407-410
In Spain, 85% of patients with genetic hemochromatosis (GH) are homozygous for the C282Y mutation of the HFE gene. H63D and S65C mutations of HFE may also play some role in the disease. The aim of this study was to establish the prevalence of C282Y, H63D, and S65C mutations of the HFE gene in newborns in Catalonia, Spain. One thousand one hundred forty-six newborn screening cards were selected randomly. DNA from these cards was extracted and HFE mutations were analyzed with the LightCycler equipment (Roche Diagnostics Gmbh, Mannheim, Germany). Sufficient DNA sample was obtained to screen for the three mutations in 1,043 cases (91%). The allelic frequencies of C282Y, H63D, and S65C mutations were 0.03 (IC 95% 0.022-0.037), 0.2 (IC 95% 0.19-0.22), and 0.01 (95% confidence interval [CI] 0.006-0.015), respectively. The frequency of C282Y homozygous newborns was 0.001 (95% CI 0.0005-0.0014). The frequencies of newborns doubly heterozygous for C282Y/H63D and C282Y/S65C were 0.01 (95% CI 0.005-0.02) and 0.002 (95% CI 0.0002-0.01), respectively. The allelic frequency of C282Y mutation is similar to that observed in Southern France, in the Czech Republic and in some areas of Italy. The allelic frequency of H63D mutation in Catalonia is the highest reported to date. Nevertheless, S65C is infrequent. These data should be kept in mind when designing hemochromatosis genotypic screening programs in Catalonia. 相似文献
13.
Sassi R Hmida S Kaabi H Hajjej A Abid A Abdelkefi S Yacoub S Maamar M Mojaat N Ben Hamed L Bellali H Dridi A Jridi A Midouni B Boukef MK 《Annales de génétique》2004,47(4):325-330
The studies of the HFE mutations: H63D and C282Y in North African populations have revealed the extreme rarity or even the absence of the C282Y mutation. We have examined 1140 chromosomes (570 Tunisian people) for the presence of the two HFE mutations by PCR-RFLP analysis. We have found that the allele frequencies are, respectively, 15.17% (+/-2.1%) for the H63D and 0.09% (+/-0.17%) for the C282Y. These results are consistent with the worldwide spread of the H63D mutation and the north European restriction of the C282Y. This study will be completed by determining whether homozygote trait for H63D and associated risk factors (beta thalassémia) can lead to iron overload in Tunisia. 相似文献
14.
15.
Zamboni P Izzo M Tognazzo S Carandina S De Palma M Catozzi L Caggiati A Scapoli G Gemmati D 《Free radical biology & medicine》2006,40(10):1869-1873
Chronic venous stasis determines red blood cell extravasation and either dermal hemosiderin deposits or iron-laden phagocytes. Several authors have suspected that iron could play a role in the pathogenesis of venous leg ulcers. They hypothesized that local iron overload could generate free radicals or activate a proteolytic hyperactivity on the part of metalloproteinases (MMPs) or else down-regulate tissue inhibitors of MMPs. However, they were unable to explain why iron deposits, visible in the legs of patients with chronic venous disease (CVD), cause lesions in only some individuals, whereas in others they do not. We hypothesized that such individual differences could be genetically determined and investigated the role of the C282Y and H63D mutations of the HFE gene. C282Y mutation significantly increases the risk of ulcer in primary CVD more than six times (OR = 6.69; 1.45-30.8; p = 0.01). Patients carrying the H63D variant have an earlier age of ulcer onset, by almost 10 years (p > 0.004). The increased risk of skin lesion and the early age of onset of the disease in HFE carriers confirm in a clinical setting that intracellular iron deposits of mutated macrophages have less stability than those of the wild type. We hypothesize that the physiologic iron protective mechanisms are affected by the HFE mutations and should be investigated in all diseases characterized by the combination of iron overload and inflammation. 相似文献
16.
In the present paper, we describe an individual, found as part of a screening study, being homozygous for the C282Y mutation and at the same time heterozygous for the H63D mutation in the HFE gene. Identical results were obtained by three different methods, i.e., by PCR-RFLP, by sequencing, and by melting curve analysis. Thus, the common conception that the C282Y and the H63D mutations are mutually exclusive is not valid. Clinical symptoms and laboratory data on the individual were similar to hemochromatosis patients homozygous for the C282Y mutation. The implications of our finding for diagnostic analytical laboratory procedures are briefly discussed. 相似文献
17.
Yang Hah-Pi 《植物分类学报:英文版》1990,28(2):136-144
Six new species, 1 new subspecies and 1 new variety are described in
this paper. They are P. salviiflora Franch. ex Forbes et Hemsl. var. leiocarpa
H. P. Yang (Ser. Salviiflorae Prain), P. rex C. B. Clarke subsp. zayuensis H. P.
Yang (Ser. Reges Li), P. xiangchengensis H. P. Yang (Ser. Cyathophyllae Li), P.
deqinensis H. P. Yang (Ser. Myriophyllae Maxim.), P. weixiensis H. P. Yang(Ser.
pectinatiformes Tsoong), P. rizhaoensis H. P. Yang (Ser. Lyratae Maxim.), P.
gongshanensis H. P. Yang (Ser. Cernuae Li), P. dulongensis H. P. Yang (Ser.
Wilsoniae Li). 相似文献
18.
Bjornson KP Blackwell LJ Sage H Baitinger C Allen D Modrich P 《The Journal of biological chemistry》2003,278(36):34667-34673
Analytical equilibrium ultracentrifugation indicates that Escherichia coli MutS exists as an equilibrating mixture of dimers and tetramers. The association constant for the dimer-to-tetramer transition is 2.1 x 10(7) M-1, indicating that the protein would consist of both dimers and tetramers at physiological concentrations. The carboxyl terminus of MutS is required for tetramer assembly because a previously described 53-amino acid carboxyl-terminal truncation (MutS800) forms a limiting species of a dimer (Obmolova, G., Ban, C., Hsieh, P., and Yang, W. (2000) Nature 407, 703-710; Lamers, M. H., Perrakis, A., Enzlin, J. H., Winterwerp, H. H., de Wind, N., and Sixma, T. K. (2000) Nature 407, 711-717). MutS800 binds a 20-base pair heteroduplex an order of magnitude more weakly than full-length MutS, and at saturating protein concentrations, the heteroduplex-bound mass observed with MutS800 is only half that observed with the full length protein, indicating that the subunit copy number of heteroduplex-bound MutS is twice that of MutS800. Analytical equilibrium ultracentrifugation using a fluorescein-tagged 20-base pair heteroduplex demonstrated that native MutS forms a tetramer on this single site-sized heteroduplex DNA. Equilibrium fluorescence experiments indicated that dimer-to-tetramer assembly promotes mismatch binding by MutS and that the tetramer can bind only a single heteroduplex molecule, implying nonequivalence of the two dimers within the tetramer. Compared with native MutS, the ability of MutS800 to promote MutL-dependent activation of MutH is substantially reduced. 相似文献
19.
The variable clinical manifestations of cystic fibrosis (CF) suggest the influence of modifier genes. Genetic and environmental factors that determine whether an individual will develop associated complications are still being determined. It has been proposed that the gene for hemochromatosis, HFE, may be a modifier locus for CF disease phenotype. Recent research has suggested a relationship between mutations to the HFE gene and the development of meconium ileus (MI) and liver disease in CF. This study aims to expand our knowledge of the HFE mutations C282Y and H63D carrier rate in an Irish population of CF allele carriers. PCR restriction enzyme analysis was performed on blood samples from CF patients to identify the C282Y and H63D mutations. HFE status of CF allele carriers and CF patients (Delta F508) homozygotes with and without meconium ileus was determined. The carrier frequency for C282Y was 30.8% for the Delta F508 homozygote MI positive group, as compared to 12.5% for the non-Delta F508 MI positive group but did not reach statistical significance (p = 0.27). Interestingly, no Delta F508 homozygote patients were homozygous for the C282Y mutation. 相似文献