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91.
Igor Tsigelny Jerry P. Greenberg Sarah Cox William L. Nichols Susan S. Taylor Lynn F. Ten Eyck 《Biopolymers》1999,50(5):513-524
Molecular dynamics simulations of the catalytic subunit of cAMP dependent protein kinase (cAPK) have been performed in an aqueous environment. The relations among the protein hydrogen‐bonding network, secondary structural elements, and the internal motions of rigid domains were examined. The values of fluctuations of protein dihedral angles during dynamics show quite distinct maxima in the regions of loops and minima in the regions of α‐helices and β‐strands. Analyses of conformation snapshots throughout the run show stable subdomains and indicate that these rigid domains are constrained during the dynamics by a stable network of hydrogen bonds. The most stable subdomain during the dynamics was in the small lobe including part of the carboxy‐terminal tail. The most significant flexible region was the highly conserved glycine‐rich loop between β strands 1 and 2 in the small lobe. Many of the main chain dihedral angle changes measured in a comparison of the crystallographic structures of “open” and “closed” conformations of cAPK correspond to the highly flexible residues found during dynamics. © 1999 John Wiley & Sons, Inc. Biopoly 50: 513–524, 1999 相似文献
92.
93.
Marlies Knipper Lika Gestwa Wouter‐Jan Ten Cate Jürgen Lautermann Heribert Brugger Hannes Maier Ulrike Zimmermann Karin Rohbock Iris Kpschall Barbara Wiechers Hans‐Peter Zenner 《Developmental neurobiology》1999,38(3):338-356
Analyzing the thyroid hromone (TH)‐dependent period of the inner ear, we observed that the presence of triiodothyronine (T3) between postnatal day 3 (P3) and P12 is sufficient for functional maturation of the auditory system. Within this short time period, an unusual transient TH‐dependent expression of nonneuronal neurotrophin receptors (NT‐R) trkB and p75NGFR was observed in correlation with neuronal and morphogenetic processes. The availability of thyroid hormone was revealed to be invariably correlated with (a) a transient expression of full‐length trkB in TRα1‐, TRα2‐ and TRβ1‐expressing hair cells concomitant to the segregation of afferent fibers and the synaptogenesis of efferent fibers; and (b) a transient expression of p75NGFR in TRα1‐ and TRβ1‐expressing great epithelia ridge cells in direct spatiotemporal correlation with the appearance of apoptotic cells and morphogenetic maturation of the organ. For the first time, these data suggest a TH dependency of the expression of neurotrophin receptors in nonneuronal cells. A potential role of these peculiar neurotrophin receptor expression for the conversion of the biological function of TH on innervation patterning and morphogenesis during the critical TH‐dependent period of the inner ear may be considered. © 1999 John Wiley & Sons, Inc. J Neurobiol 38: 338–356, 1999 相似文献
94.
Trypanosoma cruzi has many molecules that need metallic elements to work, allowing cell invasion and the establishment of infection, causing Chagas disease. Nonetheless, knowledge regarding how the parasites address metals and maintain homeostasis is lacking. To study this relationship, zinc, cadmium and mercury were chosen. Epimastigote, trypomastigote and intracellular forms of T. cruzi were incubated with these metals for different times and at different concentrations. In general, epimastigotes were the most sensitive and trypomastigotes the most resistant to metals. ZnCl2 induced low toxic effects to all parasite forms. Although the parasites were very sensitive to the toxic effects of CdCl2 and HgCl2, pretreatment with ZnCl2 decreased the death rate. The trypomastigotes pretreated with CdCl2 were unable to infect the host cells, and the treated intracellular forms were damaged after 2 h of incubation, when the toxic effects were poorly reverted. New insights on metal toxicity mechanisms are provided, helping to understand how metallic ions influence the parasite’s biochemical and physiological processes. 相似文献
95.
Gerben J. Westerhof Kristel Richters Peter M. ten Klooster 《Tijdschrift voor gerontologie en geriatrie》2017,48(1):14-24
The Well-Being Measure – dementia is a digital observation instrument that assesses the well-being of persons with dementia on four domains of quality of life: Mental well-being, Physical well-being, Participation, and Living arrangements. Its goal is to assess the well-being of persons with dementia in an easy and positive way. Besides illness-related symptoms and problems, the instrument also assesses positive aspects of functioning. It visualizes the results and provides specific behavioural advice to the caregivers. The goal of the present article is to conduct a first psychometric analysis: factor structure, reliability (Cronbach’s alpha), concurrent, and convergent validity.Observations were carried out among 168 persons with dementia in eleven different small-scale psychogeriatric wards. Five existing instruments were used among 63 persons to validate the Well-Being Measure-dementia: quality of life, neuropsychiatric symptoms, care dependency, depression, and agitation.The expected factor structure was found in each of the four domains. Coefficients were high on the expected factor and low on the other factor(s). The scale means were on the positive side, but showed an adequate range and variability. Reliability was satisfactory to good. The relation with existing scales was moderate to strong. The pattern of relations was consistent with the measurement intentions of the different existing instruments.The Well-Being Measure – dementia appears to be a valid and reliable scale. Further studies should assess its test-retest reliability, sensitivity to change and relation with the course of dementia. Current experience shows that the instrument is also useful in everyday practice. 相似文献
96.
Jae-Jin Lee Yeon-Hee Lee Su-Jin Park Seung-Yeol Lee Sangkyu Park Dae Sung Lee In-Kyu Kang Leonid N. Ten Hee-Young Jung 《Antonie van Leeuwenhoek》2017,110(3):407-414
Strain 16F3HT, a Gram-negative, aerobic, non-motile, and oval-shaped bacterium, was isolated from river water collected from the Han River in South Korea. Growth of strain 16F3HT was observed at 10–42 °C (optimum at 25–30 °C), but no growth occurred at 4 °C. The strain is able to grow at pH 4–10 (optimum at pH 7–8) and tolerates up to 4% NaCl (w/v), with optimum growth at 0.5% NaCl. The isolate was found to be resistant to UV irradiation. Based on 16S rRNA gene sequence analysis, it is closely related to ‘Deinococcus seoulensis’ 16F1E (98.8%), Deinococcus aquaticus PB314T (98.1%) and Deinococcus caeni Ho-08T (98.0%). The level of DNA–DNA homology between the novel strain and the three related strains was 57.4, 41.2, and 35.8%, respectively. Chemotaxonomic data revealed that strain 16F3HT possesses MK-8 as the predominant respiratory quinone, an unidentified phosphoglycolipid as the major polar lipid, and C15:1 ω6c and C16:1 ω7c as the major fatty acids. The DNA G + C content was determined to be 65.7 mol%. Based on polyphasic evidence, strain 16F3HT (=KCTC 33794T = JCM 31406T) should be classified as the type strain of a novel Deinococcus species, for which the name Deinococcus knuensis sp. nov. is proposed. 相似文献
97.
Cassava is infected by numerous geminiviruses in Africa and India that cause devastating losses to poor farmers. We here describe the molecular diversity of seven representative cassava mosaic geminiviruses (CMGs) infecting cassava from multiple locations in Tanzania. We report for the first time the presence of two isolates in East Africa: (EACMCV-[TZ1] and EACMCV-[TZ7]) of the species East African cassava mosaic Cameroon virus, originally described in West Africa. The complete nucleotide sequence of EACMCV-[TZ1] DNA-A and DNA-B components shared a high overall sequence identity to EACMCV-[CM] components (92% and 84%). The EACMCV-[TZ1] and -[TZ7] genomic components have recombinations in the same genome regions reported in EACMCV-[CM], but they also have additional recombinations in both components. Evidence from sequence analysis suggests that the two strains have the same ancient origin and are not recent introductions. EACMCV-[TZ1] occurred widely in the southern part of the country. Four other CMG isolates were identified: two were close to the EACMV-Kenya strain (named EACMV-[KE/TZT] and EACMV-[KE/TZM] with 96% sequence identity); one isolate, TZ10, had 98% homology to EACMV-UG2Svr and was named EACMV-UG2 [TZ10]; and finally one isolate was 95% identical to EACMV-[TZ] and named EACMV-[TZ/YV]. One isolate of African cassava mosaic virus with 97% sequence identity with other isolates of ACMV was named ACMV-[TZ]. It represents the first ACMV isolate from Tanzania to be sequenced. The molecular variability of CMGs was also evaluated using partial B component nucleotide sequences of 13 EACMV isolates from Tanzania. Using the sequences of all CMGs currently available, we have shown the presence of a number of putative recombination fragments that are more prominent in all components of EACMV than in ACMV. This new knowledge about the molecular CMG diversity in East Africa, and in Tanzania in particular, has led us to hypothesize about the probable importance of this part of Africa as a source of diversity and evolutionary change both during the early stages of the relationship between CMGs and cassava and in more recent times. The existence of multiple CMG isolates with high DNA genome diversity in Tanzania and the molecular forces behind this diversity pose a threat to cassava production throughout the African continent. 相似文献
98.
Lakeman P Gille JJ Dankert-Roelse JE Heijerman HG Munck A Iron A Grasemann H Schuster A Cornel MC Ten Kate LP 《Genetic testing》2008,12(1):25-35
AIMS: To obtain more insight into the variability of the CFTR mutations found in immigrant cystic fibrosis (CF) patients who are living in Europe now, and to estimate the test sensitivity of different frequently used methods of DNA analysis to detect CF carriers or patients among these Turkish or North African immigrants. METHODS: A survey among 373 European CF centers asking which CFTR mutations had been found in Turkish and North African CF patients. RESULTS: 31 and 26 different mutations were reported in Turkish and North African patients, identifying 64.2% (113/176) and 87.4% (118/135) alleles, respectively (p < 0.001). The mean sensitivity (detection rate) of three most common CFTR mutation panels to detect these mutations differed between Turkish and North African people, 44.9% (79/176) versus 69.6% (94/135) (p < 0.001), and can be increased to 57.4% (101/176) and 79.3% (107/135) (p < 0.001), respectively, by expanding these panels with 13 mutations which have been found on two or more alleles. CONCLUSION: 35.8% and 12.6%, respectively, of CF alleles in Turkish and North African patients living in Europe now had not been identified. Among these populations, the test sensitivity of common CFTR mutation panels is insufficient for use in screening programs in Europe, even after expansion with frequent Turkish and North African mutations. This raises questions about whether and how to implement CF carrier and neonatal screening in a multiethnic society. 相似文献
99.
100.
Celine Scornavacca Vincent Berry Vincent Lefort Emmanuel JP Douzery Vincent Ranwez 《BMC bioinformatics》2008,9(1):413