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41.
Morteza Moghaddasian Hamidreza Arab Ezzat Dadkhah Hamidreza Boostani Azam Rezaei Babak Mohammad Reza Abbaszadegan 《Gene》2014
Background
Papillon–Lefèvre syndrome (PLS) is a rare autosomal recessive disorder characterized by hyperkeratosis involving the palms, soles, elbows, and knees followed by periodontitis, destruction of alveolar bone, and loss of primary and permanent teeth. Mutations of the lysosomal protease cathepsin C gene (CTSC) have been shown to be the genetic cause of PLS. This study analyzed CTSC mutations in five Iranian families with PLS and modeled the protein for mutations found in two of them.Methods
DNA analysis was performed by direct automated sequencing of genomic DNA amplified from exonic regions and associated splice intron site junctions of CTSC. RFLP analyses were performed to investigate the presence of previously unidentified mutation(s) in control groups. Protein homology modeling of the deduced novel mutations (P35 delL and R272P) was performed using the online Swiss-Prot server for automated modeling and analyzed and tested with special bioinformatics tools to better understand the structural effects caused by mutations in cathepsin C protein (CTSC).Results
Six Iranian patients with PLS experienced premature tooth loss and palm plantar hyperkeratosis. Sequence analysis of CTSC revealed a novel mutation (P35delL) in exon 1 of Patient 1, and four previously reported mutations; R210X in Patient 2, R272P in Patient 3, Q312R in two siblings of family 4 (Patients 4 and 5), and CS043636 in Patient 6. RFLP analyses revealed different restriction fragment patterns between 50 healthy controls and patients for the P35delL mutation. Modeling of the mutations found in CTSC, P35delL in Patient 1 and R272P in Patient 3 revealed structural effects, which caused the functional abnormalities of the mutated proteins.Conclusions
The presence of this mutation in these patients provides evidence for founder CTSC mutations in PLS. This newly identified P35delL mutation leads to the loss of a leucine residue in the protein. The result of this study indicates that the phenotypes observed in these two patients are likely due to CTSC mutations. Also, structural analyses of the altered proteins identified changes in energy and stereochemistry that likely alter protein function. 相似文献42.
Matthieu Leray Laetitia G. E. Wilkins Amy Apprill Holly M. Bik Friederike Clever Sean R. Connolly Marina E. De Len J. Emmett Duffy Leïla Ezzat Sarah Gignoux-Wolfsohn Edward Allen Herre Jonathan Z. Kaye David I. Kline Jordan G. Kueneman Melissa K. McCormick W. Owen McMillan Aaron ODea Tiago J. Pereira Jillian M. Petersen Daniel F. Petticord Mark E. Torchin Rebecca Vega Thurber Elin Videvall William T. Wcislo Benedict Yuen Jonathan A. Eisen 《PLoS biology》2021,19(8)
Marine multicellular organisms host a diverse collection of bacteria, archaea, microbial eukaryotes, and viruses that form their microbiome. Such host-associated microbes can significantly influence the host’s physiological capacities; however, the identity and functional role(s) of key members of the microbiome (“core microbiome”) in most marine hosts coexisting in natural settings remain obscure. Also unclear is how dynamic interactions between hosts and the immense standing pool of microbial genetic variation will affect marine ecosystems’ capacity to adjust to environmental changes. Here, we argue that significantly advancing our understanding of how host-associated microbes shape marine hosts’ plastic and adaptive responses to environmental change requires (i) recognizing that individual host–microbe systems do not exist in an ecological or evolutionary vacuum and (ii) expanding the field toward long-term, multidisciplinary research on entire communities of hosts and microbes. Natural experiments, such as time-calibrated geological events associated with well-characterized environmental gradients, provide unique ecological and evolutionary contexts to address this challenge. We focus here particularly on mutualistic interactions between hosts and microbes, but note that many of the same lessons and approaches would apply to other types of interactions.This Essay argues that in order to truly understand how marine hosts benefit from the immense diversity of microbes, we need to expand towards long-term, multi-disciplinary research focussing on few areas of the world’s ocean that we refer to as “natural experiments,” where processes can be studied at scales that far exceed those captured in laboratory experiments. 相似文献
43.
Andaloussi SE Lehto T Mäger I Rosenthal-Aizman K Oprea II Simonson OE Sork H Ezzat K Copolovici DM Kurrikoff K Viola JR Zaghloul EM Sillard R Johansson HJ Said Hassane F Guterstam P Suhorutšenko J Moreno PM Oskolkov N Hälldin J Tedebark U Metspalu A Lebleu B Lehtiö J Smith CI Langel U 《Nucleic acids research》2011,39(9):3972-3987
44.
45.
Esposito JG Thomas SG Kingdon L Ezzat S 《American journal of physiology. Endocrinology and metabolism》2005,289(3):E494-E503
Growth hormone (GH) treatment reverses the muscle loss allegedly responsible for diminished aerobic capacity and increased fatigue in patients with HIV-associated wasting. This study examined whether submaximal measures of physical performance can be used as objective measures of the functional impact of GH treatment-induced anabolism. We randomized 27 HIV-positive men [mean (SD) age, 43.9 (7.2) yr; body mass, 71.9 (10.4) kg; BMI, 23.1 (2.8) kg/m2] with unintentional weight loss despite antiretroviral therapy to receive GH (6 mg) or placebo in a double-blinded, placebo-controlled, cross-over trial with a 3-mo washout. Lean body mass (LBM), maximum oxygen uptake (Vo2 peak), ventilatory threshold (VeT), 6-min walk test (6MWT) distance and work, profile of mood states (POMS) fatigue and vigor scores, and Nottingham health profile (NHP) energy and physical mobility scores were measured. LBM significantly increased after 3 mo of GH treatment vs. placebo (means +/- SE, 3.7 +/- 0.6 vs. 0.3 +/- 0.4 kg; P < 0.001). VeT significantly improved (17.6 +/- 3.7 vs. -5.9 +/- 2.5%; P < 0.001), but Vo2 peak did not change significantly. 6MWT distance improved (24.9 +/- 9.7 vs. 19.9 +/- 11.6 m; P > 0.05) and 6MWT work increased significantly more after 3 mo of GH treatment (33.3 +/- 8.8 vs. 16.5 +/- 7.5 kJ; P < 0.05). POMS scores of fatigue and vigor and the NHP score of energy improved, yet the changes were not statistically significant. GH treatment improved VeT linearly to the increase in LBM (r =0.43, P = 0.037) and 6MWT work (r = 0.51, P = 0.008), and the increase in 6MWT work correlated with increase in LBM (r = 0.45, P = 0.024). Improvement in 6MWT work above the median (27.3 kJ) showed a decrease in fatigue (r = -0.62, P = 0.024). We concluded that GH treatment-induced LBM gains in HIV-associated wasting were functionally relevant, as determined by effort-independent submaximal measures of cardiopulmonary exercise testing. 相似文献
46.
Theodore A.W. Koerner Ronald J. Voll Lewis W. Cary Ezzat S. Younathan 《Biochemical and biophysical research communications》1978,82(4):1273-1278
Several disagreements in the 13C n.m.r. assignments of the methine carbons of D-fructose exist in the literature. In order to settle these inconsistencies, we examined the 13C n.m.r. spectrum of 3-O-methyl-D-fructose. By following the methyl induced shift in this spectrum, as compared to the parent sugar, we identified the alkylated C-3 resonance of all four tautomeric forms of D-fructose. This information, together with our previous identification of the C-5 resonances of the α- and β-forms of D-fructofuranose 6-phosphate, allow the unambiguous identification of all methine carbons of D-fructose in its 13C n.m.r. spectrum. The tautomeric composition of 3-O-methyl-D-fructose at 16.5°, in aqueous solution, was found to be as follows: α-pyranose 18%, β-pyranose 37%, α-furanose 11% and β-furanose 34%. 相似文献
47.
Theodore A.W. Koerner Lewis W. Cary Norman S. Bhacca Ezzat S. Younathan 《Biochemical and biophysical research communications》1973,51(3):543-550
The Fourier transform 13C magnetic resonance spectra of D-fructose 6-phosphate (F6P) and D-fructose 1,6-diphosphate (FDP) were obtained. The signal assignments made on the basis of 13C chemical shifts and 13C-31P spin-spin couplings indicate that the earlier assignments of the C-4 and C-5 resonances of α- and β-fructofuranose in oligosaccharides and D-fructose [Allerhand, A. and Doddrell, D., J. Amer. Chem. Soc., , 2777, 2779 (1971)] should be reversed. Integration of signal intensities yields the following equilibrium composition at 35°C: F6P, α-anomer 19±2% and β-anomer 81±2%, FDP, α-anomer 23±4% and β-anomer 77±4%. Less than 1.5% keto or hydrated keto form is present in solutions of either fructose phosphate. The bearing of these findings on the tautomeric specificity of phosphofructokinase is discussed. 相似文献
48.
Summary The Egyptian Zygophyllum species, though limited in number, contribute in considerable measure to the desert vegetation. They represent a group of succulent plants which are drought resistant or salt tolerant living under severe dry climatic conditions. Their abundance is attributed to these characteristics in addition to their unpalatibility.The distribution of the studied species is deduced from the data collected by the present authors and others working in the Egyptian desert. The growth and distribution of some Zygophyllum species are dependant on the chemical nature of the substratum. Z. occineum is a widespread species in the limestone territories of the Eastern desert. Z. decumbens is confined to a limited area within the borders of the area inhabited by Z. coccineum. Z. album is a salt tolerant plant with wide geographical range growing in dry littoral or inland salt marshes. Z. simplex, the only ephemeral species, has wide geographical and ecological ranges. The soil carbonate content does not exercise any significant effect on its distribution though it is more ecologically related to Z. occineum than the other species. Z. decumbens is ecologically related to Z. coccineum, while Z. album has its own ecological amplitude. 相似文献
49.
Catherine Metayer Elizabeth Milne Jacqueline Clavel Claire Infante-Rivard Eleni Petridou Malcolm Taylor Joachim Schüz Logan G. Spector John D. Dockerty Corrado Magnani Maria S. Pombo-de-Oliveira Daniel Sinnett Michael Murphy Eve Roman Patricia Monge Sameera Ezzat Beth A. Mueller Michael E. Scheurer Patricia A. Buffler 《Cancer epidemiology》2013,37(3):336-347
Background: Acute leukemia is the most common cancer in children under 15 years of age; 80% are acute lymphoblastic leukemia (ALL) and 17% are acute myeloid leukemia (AML). Childhood leukemia shows further diversity based on cytogenetic and molecular characteristics, which may relate to distinct etiologies. Case–control studies conducted worldwide, particularly of ALL, have collected a wealth of data on potential risk factors and in some studies, biospecimens. There is growing evidence for the role of infectious/immunologic factors, fetal growth, and several environmental factors in the etiology of childhood ALL. The risk of childhood leukemia, like other complex diseases, is likely to be influenced both by independent and interactive effects of genes and environmental exposures. While some studies have analyzed the role of genetic variants, few have been sufficiently powered to investigate gene–environment interactions. Objectives: The Childhood Leukemia International Consortium (CLIC) was established in 2007 to promote investigations of rarer exposures, gene–environment interactions and subtype-specific associations through the pooling of data from independent studies. Methods: By September 2012, CLIC included 22 studies (recruitment period: 1962–present) from 12 countries, totaling approximately 31 000 cases and 50 000 controls. Of these, 19 case–control studies have collected detailed epidemiologic data, and DNA samples have been collected from children and child–parent trios in 15 and 13 of these studies, respectively. Two registry-based studies and one study comprising hospital records routinely obtained at birth and/or diagnosis have limited interview data or biospecimens. Conclusions: CLIC provides a unique opportunity to fill gaps in knowledge about the role of environmental and genetic risk factors, critical windows of exposure, the effects of gene–environment interactions and associations among specific leukemia subtypes in different ethnic groups. 相似文献
50.