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91.
Maturity Onset Diabetes of the Young (MODY) is a heterogeneous group of genetic diseases characterized by a primary defect in insulin secretion and hyperglycemia, non-ketotic disease, monogenic autosomal dominant mode of inheritance, age at onset less than 25 years, and lack of auto-antibodies. It accounts for 2–5% of all cases of non-type 1 diabetes. MODY subtype 2 is caused by mutations in the glucokinase (GCK) gene. In this study, we sequenced the GCK gene of two volunteers with clinical diagnosis for MODY2 and we were able to identify four mutations including one for a premature stop codon (c.76C>T). Based on these results, we have developed a specific PCR-RFLP assay to detect this mutation and tested 122 related volunteers from the same family. This mutation in the GCK gene was detected in 21 additional subjects who also had the clinical features of this genetic disease. In conclusion, we identified new GCK gene mutations in a Brazilian family of Italian descendance, with one due to a premature stop codon located in the second exon of the gene. We also developed a specific assay that is fast, cheap and reliable to detect this mutation. Finally, we built a molecular ancestry model based on our results for the migration of individuals carrying this genetic mutation from Northern Italy to Brazil. 相似文献
92.
Dominik Refardt Tobias Bergmiller Rolf Kümmerli 《Proceedings. Biological sciences / The Royal Society》2013,280(1759)
High relatedness among interacting individuals has generally been considered a precondition for the evolution of altruism. However, kin-selection theory also predicts the evolution of altruism when relatedness is low, as long as the cost of the altruistic act is minor compared with its benefit. Here, we demonstrate evidence for a low-cost altruistic act in bacteria. We investigated Escherichia coli responding to the attack of an obligately lytic phage by committing suicide in order to prevent parasite transmission to nearby relatives. We found that bacterial suicide provides large benefits to survivors at marginal costs to committers. The cost of suicide was low, because infected cells are moribund, rapidly dying upon phage infection, such that no more opportunity for reproduction remains. As a consequence of its marginal cost, host suicide was selectively favoured even when relatedness between committers and survivors approached zero. Altogether, our findings demonstrate that low-cost suicide can evolve with ease, represents an effective host-defence strategy, and seems to be widespread among microbes. Moreover, low-cost suicide might also occur in higher organisms as exemplified by infected social insect workers leaving the colony to die in isolation. 相似文献
93.
Cláudia N. Santos Marta Alves António Oliveira Ricardo B. Ferreira 《Journal of plant physiology》2013
Glycosylation is an important post-translational modification involved in the modulation of a wide variety of cellular processes. Because glycosydases are central, the aim of this study was to investigate the glycosyl activity present in the cotyledons of the seeds of an important crop legume, Lupinus albus, as well as potential natural substrates of the detected enzymes. 相似文献
94.
Cahara Ghauri from China with three species is reviewed here. Two of them, Cahara incisura
sp. n. and Cahara nodula
sp. n. are described here. Key to the three Chinese species, habitus photographs and illustrations of genitalia are also provided. All examined materials including the types of three species mentioned are deposited in the Institute of Entomology, Nankai University, Tianjin, China (NKUM). 相似文献
95.
V. Selvakumar P. R. Anbudurai T. Balakumar 《In vitro cellular & developmental biology. Plant》2001,37(2):280-284
Summary A protocol for rapid in vitro propagation using nodal explants obtained from 2-yr-old, field-grown medicinal plants of Plumbago zeylanica L. belonging to the family Plumbaginaceae is described. High frequency bud break and fast development of shoots were induced
on Murashige and Skoog's basal medium supplemented with 27.2 μM adenine sulfate +2.46 μM indole-3-butyric acid (IBA). Induction of rooting was achieved by transferring the shoots to the same basal medium containing
4.92 μM IBA. Using our protocol from one twig of P. zeylanica (eight responsive nodes per explant shoot) within a period of 5 mo., eight plantlets could be raised. After a hardening period
of 4 wk, there was a 90% transplantation success in the field compared to the 60–65% survival of plantlets recorded in the
experiments of previous workers. The plantlets derived through in vitro propagation mimic the growth and morphological characteristics of the donor plants. 相似文献
96.
Masayo Suzuki Hiroyuki Ishida Yukimasa Shiotsu Taisuke Nakata Shiro Akinaga Shigemitsu Takashima Toshiaki Utsumi Toshiaki Saeki Nobuhiro Harada 《The Journal of steroid biochemistry and molecular biology》2009,113(3-5):195-201
In order to evaluate the importance of estrogen production in tumor and surrounding tissues, we measured mRNA expression levels of 5 enzymes participating to estrogen synthesis in situ and 4 breast cancer-related proteins in 27 pairs of tumor and non-malignant tissues. Steroid sulfatase (STS) mRNA was more frequently detected in tumor tissues rather than in their non-malignant counterparts. Estrogen sulfotransferase (EST) was constantly expressed with high level not only in tumor tissues but also in their surrounding non-malignant counterparts. In contrast, mRNA expression levels of aromatase, and 17β-hydroxysteroid dehydrogenase type I and II were relatively low and detected only in small proportion of the patients. We also measured the mRNA expression levels of the same nine genes in tumor tissues of 197 breast cancer patients, and analyzed relationship between the mRNA expression level and the clinicopathological parameters. The mRNA expression levels of STS, aromatase and erbB2 in tumor tissues increased as breast cancer progressed. The tumoral mRNA expression levels of STS, estrogen receptor β, and erbB2 in patients with recurrence were higher than those in patients without recurrence. Upregulation of STS expression plays an important role in tumor progression of human breast cancer and is considered to be responsible for estrogen production in tumor and surrounding tissues. 相似文献
97.
Roger Cardinal 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2009,364(1522):1459-1466
Outsider Art (art brut) is defined as a mode of original artistic expression which thrives on its independence, shunning the public sphere and the art market. Such art can be highly idiosyncratic and secretive, and reflects the individual creator''s attempt to construct a coherent, albeit strange, private world. Certain practitioners of what may be termed autistic art are examined in the light of this definition; their work is considered as evidence not of a medical condition but of an expressive intentionality entirely worthy of the interest of those drawn to the aesthetic experience. 相似文献
98.
John J. LiPuma 《Journal of nematology》2003,35(2):212-217
Although sporadic human infection due to Burkholderia cepacia has been reported for many years, it has been only during the past few decades that species within the B. cepacia complex have emerged as significant opportunistic human pathogens. Individuals with cystic fibrosis, the most common inherited genetic disease in Caucasian populations, or chronic granulomatous disease, a primary immunodeficiency, are particularly at risk of life-threatening infection. Despite advances in our understanding of the taxonomy, microbiology, and epidemiology of B. cepacia complex, much remains unknown regarding specific human virulence factors. The broad-spectrum antimicrobial resistance demonstrated by most strains limits current therapy of infection. Recent research efforts are aimed at a better appreciation of the pathogenesis of human infection and the development of novel therapeutic and prophylactic strategies. 相似文献
99.
Lens includes L.
culinaris subsp. culinaris (the cultivated lentil) and several wild species distributed from the Mediterranean region to western Asia. We compared sequence
variation in the ITS region among species of Lens in an effort to end persisting uncertainty regarding the phylogeny of the genus. The parsimony analysis revealed a single
minimum-length tree with a topology congruent with patterns derived by previous studies of nuclear and chloroplast DNA RFLPs.
The basal and highly divergent status of the L. nigricans clade is depicted, and the progenitor-derivative relationship between L. culinaris subsp. orientalis and L. culinaris subsp. culinaris is reaffirmed. Resolution in the tree was improved by combining the ITS data set with a pre-existing set of chloroplast DNA
restriction site data obtained from the same group of samples.
Received May 8, 2000 Accepted October 26, 2001 相似文献
100.
M. R. Duvall 《Plant Systematics and Evolution》2001,228(3-4):143-152
Critical morphological synapomorphies have not been found in support of the Acoranan hypothesis, the molecular phylogenetic
discovery that Acoranae are the basal monocots. The previously undetermined pattern of anther wall development in Acorus has been suggested to be one such character. Two main types of anther wall development have been recognized: 1) the “monocotyledonous”
type, which characterizes both monocots and dicots, and 2) the “dicotyledonous” type, which is almost exclusively found among
dicots. An anatomical study of anther wall development in Acorus was here undertaken using the electron microscope. Development of the anther wall in Acorus was found to be somewhat irregular or perhaps even intermediate between the two types although largely consistent with the
“monocotyledonous” type. The presumed significance of anther wall development and other critical morphological characters
to the Acoranan hypothesis in the absence of knowledge about the sister group to the monocots is evaluated.
Received August 28, 2000 Accepted February 19, 2001 相似文献