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61.
Fine mapping of the Autosomal Dominant Split Hand/Split Foot Locus on Chromosome 7, Band q21.3-q22.1 总被引:6,自引:3,他引:3 下载免费PDF全文
Stephen W. Scherer Parvoneh Poorkaj Todd Allen Julia Kim Dorrit Geshuri Mark Nunes Sylvia Soder Karen Stephens Roberta A. Pagon Michael A. Patton Mary Anne Berg Tim Donlon Horacio Rivera R. A. Pfeiffer Kenji Naritomi Helen Hughes Maurizio Genuardi Fiorella Gurrieri Giovanni Neri Everett Lovrein Ellen Magenis Lap-Chee Tsui James P. Evans 《American journal of human genetics》1994,55(1):12-20
Split hand/split foot (SHFD) is a human developmental defect characterized by missing digits, fusion of remaining digits, and a deep median cleft in the hands and feet. Cytogenetic studies of deletions and translocations associated with this disorder have indicated that an autosomal dominant split hand/split foot locus (gene SHFD1) maps to 7q21-q22. To characterize the SHFD1 locus, somatic cell hybrid lines were constructed from cytogenetically abnormal individuals with SHFD. Molecular analysis resulted in the localization of 93 DNA markers to one of 10 intervals surrounding the SHFD1 locus. The translocation breakpoints in four SHFD patients were encompassed by the smallest region of overlap among the SHFD-associated deletions. The order of DNA markers in the SHFD1 critical region has been defined as PON–D7S812–SHFD1–D7S811–ASNS. One DNA marker, D7S811, detected altered restriction enzyme fragments in three patients with translocations when examined by pulsed-field gel electro-phoresis (PFGE). These data map SHFD1, a gene that is crucial for human limb differentiation, to a small interval in the q21.3-q22.1 region of human chromosome 7. 相似文献
62.
Michael Dean J. Claiborne Stephens Cheryl Winkler Deborah A. Lomb Mark Ramsburg Raleigh Boaze Claudia Stewart Lauren Charbonneau David Goldman Bernard J. Albaugh James J. Goedert R. Palmer Beasley Lu-Yu Hwang Susan Buchbinder Michael Weedon Patricia A. Johnson Mary Eichelberger Stephen J. O'Brien 《American journal of human genetics》1994,55(4):788-808
A panel of 257 RFLP loci was selected on the basis of high heterozygosity in Caucasian DNA surveys and equivalent spacing throughout the human genome. Probes from each locus were used in a Southern blot survey of allele frequency distribution for four human ethnic groups: Caucasian, African American, Asian (Chinese), and American Indian (Cheyenne). Nearly all RFLP loci were polymorphic in each group, albeit with a broad range of differing allele frequencies (δ). The distribution of frequency differences (δ values) was used for three purposes: (1) to provide estimates for genetic distance (differentiation) among these ethnic groups, (2) to revisit with a large data set the proportion of human genetic variation attributable to differentiation within ethnic groups, and (3) to identify loci with high δ values between recently admixed populations of use in mapping by admixture linkage disequilibrium (MALD). Although most markers display significant allele frequency differences between ethnic groups, the overall genetic distances between ethnic groups were small (.066–.098), and <10% of the measured overall molecular genetic diversity in these human samples can be attributed to “racial” differentiation. The median δ values for pairwise comparisons between groups fell between .15 and .20, permitting identification of highly informative RFLP loci for MALD disease association studies. 相似文献
63.
Sonia R. Virdee Godfrey M. Hewitt 《Evolution; international journal of organic evolution》1994,48(2):392-407
Two subspecies of the grasshopper Chorthippus parallelus meet in the Pyrenees forming a hybrid zone several kilometers wide. Crosses between the two pure taxa result in sterile male offspring and normal females (i.e., Haldane's rule applies). However, no such dysfunction has been detected in hybrid males collected through the center of the hybrid zone. By assessing the level of dysfunction in the offspring of reciprocal crosses, it was possible to map clines for the genes responsible for dysfunction through the zone. This analysis shows that there is no abrupt transition between incompatible genomes in the field. Crosses were also made between females collected from a transect spanning the hybrid zone and pure males of both subspecies. This reveals noncoincident clines for dysfunction near the center of the hybrid zone such that the dysfunction expressed in the offspring of these crosses is less than expected from simple models. More complex models involving interaction among genes must be invoked. Also, the possibility exists that since the postglacial contact of these two grasshopper taxa, hybrid dysfunction has become ameliorated by the evolution of modifiers. This hybrid zone is thought to be a tension zone, maintained by a balance between selection against hybrid genotypes and dispersal into the zone center. The lessening of hybrid disadvantage over time through the breakdown of epistatic interactions by recombination or through modification could account for the general lack of dysfunction in field collected hybrids today. 相似文献
64.
65.
Beatriz Ernestina Cabilio Guth Eliana Gonalves Aguiar Patricia Marie Griffin Sonia Regina Testa da Silva Ramos Tnia Aparecida Tardelli Gomes 《Microbiology and immunology》1994,38(9):695-701
Fifty-eight enterotoxigenic Escherichia coli (ETEC) strains, isolated from children with and without diarrhea in Sao Paulo, were examined for the presence of colonization factor antigens (CFAs) and their ability to adhere to HeLa cells. Antisera to CFA/I, the coli surface (CS) antigens CS1CS3, CS2CS3, and CS2 of CFA/II, CFA/III, and CS5CS6 and CS6 of CFA/IV were used. CFAs were identified in 43% of the ETEC strains: 40% of the strains with CFAs harbored CFA/I, 24% carried CFA/II (CS1CS3), 24% carried CFA/IV (CS6), and 12% carried CFA/IV (CS5CS6). CFAs occurred mainly among ETEC strains producing only heat-stable (ST-I) enterotoxin and in strains also producing heat-labile toxin (LT-I). No ETEC strains tested expressed CFA/III. A marked change in serotypes of ST-I-producing strains was found in Sao Paulo between 1979 and 1990. Adherence to HeLa cells was detected in 14% of the ETEC strains. All of them had a diffuse adherence pattern and produced only ST-I, and 88% carried CS6 antigen. 相似文献
66.
67.
Genetic analysis of the virD operon of Agrobacterium tumefaciens: a search for functions involved in transport of T-DNA into the plant cell nucleus and in T-DNA integration. 总被引:9,自引:5,他引:4 下载免费PDF全文
Z Koukolíkov-Nicola D Raineri K Stephens C Ramos B Tinland E W Nester B Hohn 《Journal of bacteriology》1993,175(3):723-731
The transferred DNA (T-DNA) is transported from Agrobacterium tumefaciens to the nucleus and is stably integrated into the genome of many plant species. It has been proposed that the VirD2 protein, tightly attached to the T-DNA, pilots the T-DNA into the plant cell nucleus and that it is involved in integration. Using agroinfection and beta-glucuronidase expression as two different very sensitive transient assays for T-DNA transfer, together with assays for stable integration, we have shown that the C-terminal half of the VirD2 protein and the VirD3 protein are not involved in T-DNA integration. However, the bipartite nuclear localization signal, which is located within the C terminus of the VirD2 protein and which has previously been shown to be able to target a foreign protein into the plant cell nucleus, was shown to be required for efficient T-DNA transfer. virD4 mutants were shown by agroinfection to be completely inactive in T-DNA transfer. 相似文献
68.
Niche breadth explains the range size of European-centred butterflies,but dispersal ability does not
Johannes Hausharter Sonia Rashid Johannes Wessely Patrick Strutzenberger Dietmar Moser Andreas Gattringer Konrad Fiedler Karl Hülber Stefan Dullinger 《Global Ecology and Biogeography》2023,32(9):1535-1548
Aim
The breadth of ecological niches and dispersal abilities have long been discussed as important determinants of species' range sizes. However, studies directly comparing the relative effects of both factors are rare, taxonomically biased and revealed inconsistent results.Location
Europe.Time Period
Cenozoic.Major Taxa
Butterflies, Lepidoptera.Methods
We relate climate, diet and habitat niche breadth and two indicators of dispersal ability, wingspan and a dispersal tendency index, to the global range size of 369 European-centred butterfly species. The relative effects of these five predictors and their variation across the butterfly phylogeny were assessed by means of phylogenetic generalized least squares models and phylogenetically weighted regressions respectively.Results
Climate niche breadth was the most important single predictor, followed by habitat and diet niche breadth, while dispersal tendency and wingspan showed no relation to species' range size. All predictors together explained 59% of the variation in butterfly range size. However, the effects of each predictor varied considerably across families and genera.Main Conclusions
Range sizes of European-centred butterflies are strongly correlated with ecological niche breadth but apparently independent of dispersal ability. The magnitude of range size–niche breadth relationships is not stationary across the phylogeny and is often negatively correlated across the different dimensions of the ecological niche. This variation limits the generalizability of range size–trait relationships across broad taxonomic groups. 相似文献69.
Sonia Mannan Jobair Alam K. M. Ashbarul Bari S. M. A. A. Mamun Rehnuma Mehzabin Orin 《Developing world bioethics》2023,23(3):252-259
Informed consent to medical intervention is fundamental in both ethics and law. But in practice it is often not taken seriously in developing countries. This paper provides an appraisal of informed consent practices in Bangladesh. Following a review of the ethical and legal principles of informed consent, it assesses the degree to which doctors adhere to it in Bangladesh. Based on findings of non-compliance, it then investigates the reasons for such non-compliance through an appraisal of informed consent practices in Bangladesh and provides recommendations aimed at improving such practices. The significance of this paper lies in unveiling the interdependence between the ethical and legal traits of informed consent and their ramifications on strengthening the patient-oriented approach of duty to care. 相似文献
70.
Fatemeh Davodabadi Shekoufeh Mirinejad Sonia Fathi-Karkan Mahdi Majidpour Narges Ajalli Roghayeh Sheervalilou Saman Sargazi Dominika Rozmus Abbas Rahdar Ana M. Diez-Pascual 《Biotechnology progress》2023,39(5):e3366
Aptamers (Apts) are synthetic nucleic acid ligands that can be engineered to target various molecules, including amino acids, proteins, and pharmaceuticals. Through a series of adsorption, recovery, and amplification steps, Apts are extracted from combinatorial libraries of synthesized nucleic acids. Using aptasensors in bioanalysis and biomedicine can be improved by combining them with nanomaterials. Moreover, Apt-associated nanomaterials, including liposomes, polymeric, dendrimers, carbon nanomaterials, silica, nanorods, magnetic NPs, and quantum dots (QDs), have been widely used as promising nanotools in biomedicine. Following surface modifications and conjugation with appropriate functional groups, these nanomaterials can be successfully used in aptasensing. Advanced biological assays can use Apts immobilized on QD surfaces through physical interaction and chemical bonding. Accordingly, modern QD aptasensing platforms rely on interactions between QDs, Apts, and targets to detect them. QD-Apt conjugates can be used to directly detect prostate, ovarian, colorectal, and lung cancers or simultaneously detect biomarkers associated with these malignancies. Tenascin-C, mucin 1, prostate-specific antigen, prostate-specific membrane antigen, nucleolin, growth factors, and exosomes are among the cancer biomarkers that can be sensitively detected using such bioconjugates. Furthermore, Apt-conjugated QDs have shown great potential for controlling bacterial infections such as Bacillus thuringiensis, Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, Campylobacter jejuni, Staphylococcus aureus, and Salmonella typhimurium. This comprehensive review discusses recent advancements in the design of QD-Apt bioconjugates and their applications in cancer and bacterial theranostics. 相似文献