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71.
Karina Tuz Ruxandra Bachmann-Gagescu Diana?R. O’Day Kiet Hua Christine?R. Isabella Ian?G. Phelps Allan?E. Stolarski Brian?J. O’Roak Jennifer?C. Dempsey Charles Lourenco Abdulrahman Alswaid Carsten?G. B?nnemann Livija Medne Sheela Nampoothiri Zornitza Stark Richard?J. Leventer Meral Top?u Ali Cansu Sujatha Jagadeesh Stephen Done Gisele?E. Ishak Ian?A. Glass Jay Shendure Stephan?C.F. Neuhauss Chad?R. Haldeman-Englert Dan Doherty Russell?J. Ferland 《American journal of human genetics》2014,94(1):62-72
Joubert syndrome (JBTS) is a recessive ciliopathy in which a subset of affected individuals also have the skeletal dysplasia Jeune asphyxiating thoracic dystrophy (JATD). Here, we have identified biallelic truncating CSPP1 (centrosome and spindle pole associated protein 1) mutations in 19 JBTS-affected individuals, four of whom also have features of JATD. CSPP1 mutations explain ∼5% of JBTS in our cohort, and despite truncating mutations in all affected individuals, the range of phenotypic severity is broad. Morpholino knockdown of cspp1 in zebrafish caused phenotypes reported in other zebrafish models of JBTS (curved body shape, pronephric cysts, and cerebellar abnormalities) and reduced ciliary localization of Arl13b, further supporting loss of CSPP1 function as a cause of JBTS. Fibroblasts from affected individuals with CSPP1 mutations showed reduced numbers of primary cilia and/or short primary cilia, as well as reduced axonemal localization of ciliary proteins ARL13B and adenylyl cyclase III. In summary, CSPP1 mutations are a major cause of the Joubert-Jeune phenotype in humans; however, the mechanism by which these mutations lead to both JBTS and JATD remains unknown. 相似文献
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Helena de Freitas Oliveira Paranhos Claudia Helena Lovato da Silva Raphael Freitas De Souza Karina Matthes de Freitas Pontes 《Gerodontology》2010,27(1):33-40
doi:10.1111/j.1741‐2358.2009.00285.x Evaluation of three indices for biofilm accumulation on complete dentures Objectives: The objective of this study was to evaluate the accuracy and reproducibility of three complete denture biofilm indices (Prosthesis Hygiene Index; Jeganathan et al. Index; Budtz‐Jørgensen Index) by means of a computerised comparison method. Background: Clinical studies into denture hygiene have employed a large number of biofilm indices among their outcome variables. However, the knowledge about the validity of these indices is still scarce. Materials and methods: Sixty‐two complete denture wearers were selected. The internal surfaces of the upper complete dentures were stained (5% erythrosine) and photographed. The slides were projected on paper, and the biofilm indices were applied over the photos by means of a scoring method. For the computerised method, the areas (total and biofilm‐covered) were measured by dedicated software (Image Tool). In addition, to compare the results of the computerised method and Prosthetic Hygiene Index, a new scoring scale (including four and five graded) was introduced. For the Jeganathan et al. and Budtz‐Jørgensen indices, the original scales were used. Values for each index were compared with the computerised method by the Friedman test. Their reproducibility was measured by means of weighed κ. Significance for both tests was set at 0.05. Results: The indices tested provided similar mean measures but they tended to overestimate biofilm coverage when compared with the computerised method (p < 0.001). Agreement between the Prosthesis Hygiene Index and the computerised method was not significant, regardless of the scale used. Jeghanathan et al. Index showed weak agreement, and consistent results were found for Budtz‐Jorgensen Index (κ = 0.19 and 0.39 respectively). Conclusion: Assessment of accuracy for the biofilm indices showed instrument bias that was similar among the tested methods. Weak inter‐instrument reproducibility was found for the indices, except for the Budtz‐Jørgensen Index. This should be the method of choice for clinical studies when more sophisticated approaches are not possible. 相似文献
75.
Microbial communities and chemical changes during fermentation of sugary Brazilian kefir 总被引:2,自引:0,他引:2
Karina Teixeira Magalhães G. V. de M. Pereira Disney Ribeiro Dias Rosane Freitas Schwan 《World journal of microbiology & biotechnology》2010,26(7):1241-1250
The microorganisms associated with sugary Brazilian kefir beverage were investigated using a combination of culture-dependent
and -independent methods. A total of 289 bacteria and 129 yeasts were identified via phenotypic and genotypic methods. Lb. paracasei (23.8%) was the major bacterial isolate identified, followed by Acetobacter
lovaniensis (16.31%), Lactobacillus parabuchneri (11.71%), Lactobacillus kefir (10.03%) and Lactococcus lactis (10.03%). Saccharomyces cerevisiae (54.26%) and Kluyveromyces lactis (20.15%) were the most common yeast species isolated. Scanning electron microscopy showed that the microbiota was dominated
by lemon-shaped yeast cells growing in close association with Lactobacillus (long and curved). Some lactic acid bacteria detected by sequence analysis of DGGE (denaturing gradient gel electrophoresis)
bands were not recovered at any time through fermentation by plating. Conversely, DGGE fingerprints did not reveal bands corresponding
to some of the species isolated by culturing methods. The bacteria Acetobacter lovaniensis and the yeast Kazachstania aerobia are described for the first time in sugary kefir. During the 24 h of fermentation, the concentration of lactic acid ranged
from 0.2 to 1.80 mg/ml, and that of acetic acid increased from 0.08 to 1.12 mg/ml. The production of ethanol was limited,
reaching a final mean value of 1.24 mg/ml. 相似文献
76.
Lívia Santos Lima Karina Peres Gramacho José Luis Pires Didier Clement Uilson Vanderlei Lopes Nicolas Carels Abelmon da Silva Gesteira Fernanda Amato Gaiotto Júlio Cézar de Mattos Cascardo Fabienne Micheli 《Tree Genetics & Genomes》2010,6(5):663-676
In this study, we report results of the detection and analysis of SSR markers derived of cacao–Moniliophthora perniciosa expressed sequence tags (ESTs) in relation to cacao resistance to witches’ broom disease (WBD), and we compare the polymorphism
of those ESTs (EST-simple sequence repeat (SSR)) with classical neutral SSR markers. A total of 3,487 ESTs was used in this
investigation. SSRs were identified in 430 sequences: 277 from the resistant genotype TSH 1188 and 153 from the susceptible
one Catongo, totalizing 505 EST-SSRs with three types of motifs: dinucleotides (72.1%), trinucleotides (27.3%), and tetranucleotides
(0.6%). EST-SSRs were classified into 16 main categories; most of the EST-SSRs belonged to “Unknown function” and “No homology”
categories (45.82%). A high frequency of SSRs was found in the 5’UTR and in the ORF (about 27%) and a low frequency was observed
in the 3’UTR (about 8%). Forty-nine EST-SSR primers were designed and evaluated in 21 cacao accessions, 12 revealed polymorphism,
having 47 alleles in total, with an average of 3.92 alleles per locus. On the other hand, the 11 genomic SSR markers revealed
a total of 47 alleles, with an average of 5.22 alleles per locus. The association of EST-SSR with the genomic SSR enhanced
the analysis of genetic distance among the genotypes. Among the 12 polymorphic EST-SSR markers, two were mapped on the F2 Sca 6 × ICS 1 population reference for WBD resistance. 相似文献
77.
Rituraj Pal Karina Schnittker 《Biochemical and biophysical research communications》2010,392(4):567-571
Protein disulfide isomerase (PDI), the chief endoplasmic reticulum (ER) resident oxidoreductase chaperone that catalyzes maturation of disulfide-bond-containing proteins is involved in the pathogenesis of both Parkinson’s (PD) and Alzheimer’s (AD) diseases. S-nitrosylation of PDI cysteines due to nitrosative stress is associated with cytosolic debris accumulation and Lewy-body aggregates in PD and AD brains. We demonstrate that the polyphenolic phytochemicals curcumin and masoprocol can rescue PDI from becoming S-nitrosylated and maintain its catalytic function under conditions mimicking nitrosative stress by forming stable NOx adducts. Furthermore, both polyphenols intervene to prevent the formation of PDI-resistant polymeric misfolded protein forms that accumulate upon exposure to oxidative stress. Our study suggests that curcumin and masoprocol can serve as lead-candidate prophylactics for reactive oxygen species induced chaperone damage, protein misfolding and neurodegenerative disease; importantly, they can play a vital role in sustaining traffic along the ER’s secretory pathway by preserving functional integrity of PDI. 相似文献
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Janaína A Couto Karina LA Saraiva Cleiton D Barros Daniel P Udrisar Christina A Peixoto Juliany SB César Vieira Maria C Lima Suely L Galdino Ivan R Pitta Maria I Wanderley 《Reproductive biology and endocrinology : RB&E》2010,8(1):13
Background
The present study was designed to examine the effect of chronic treatment with rosiglitazone - thiazolidinedione used in the treatment of type 2 diabetes mellitus for its insulin sensitizing effects - on the Leydig cell steroidogenic capacity and expression of the steroidogenic acute regulatory protein (StAR) and cholesterol side-chain cleavage enzyme (P450scc) in normal adult rats. 相似文献80.
Latitudinal and altitudinal patterns of plant community diversity on mountain summits across the tropical Andes 下载免费PDF全文
Francisco Cuesta Priscilla Muriel Luis Daniel Llambí Stephan Halloy Nikolay Aguirre Stephan Beck Julieta Carilla Rosa Isela Meneses Soledad Cuello Alfredo Grau Luis E. Gámez Javier Irazábal Jorge Jácome Ricardo Jaramillo Lirey Ramírez Natalia Samaniego David Suárez‐Duque Natali Thompson Alfredo Tupayachi Paul Viñas Karina Yager María T. Becerra Harald Pauli William D. Gosling 《Ecography》2017,40(12):1381-1394
The high tropical Andes host one of the richest alpine floras of the world, with exceptionally high levels of endemism and turnover rates. Yet, little is known about the patterns and processes that structure altitudinal and latitudinal variation in plant community diversity. Herein we present the first continental‐scale comparative study of plant community diversity on summits of the tropical Andes. Data were obtained from 792 permanent vegetation plots (1 m2) within 50 summits, distributed along a 4200 km transect; summit elevations ranged between 3220 and 5498 m a.s.l. We analyzed the plant community data to assess: 1) differences in species abundance patterns in summits across the region, 2) the role of geographic distance in explaining floristic similarity and 3) the importance of altitudinal and latitudinal environmental gradients in explaining plant community composition and richness. On the basis of species abundance patterns, our summit communities were separated into two major groups: Puna and Páramo. Floristic similarity declined with increasing geographic distance between study‐sites, the correlation being stronger in the more insular Páramo than in the Puna (corresponding to higher species turnover rates within the Páramo). Ordination analysis (CCA) showed that precipitation, maximum temperature and rock cover were the strongest predictors of community similarity across all summits. Generalized linear model (GLM) quasi‐Poisson regression indicated that across all summits species richness increased with maximum air temperature and above‐ground necromass and decreased on summits where scree was the dominant substrate. Our results point to different environmental variables as key factors for explaining vertical and latitudinal species turnover and species richness patterns on high Andean summits, offering a powerful tool to detect contrasting latitudinal and altitudinal effects of climate change across the tropical Andes. 相似文献