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31.
Integrating biogeography,threat and evolutionary data to explore extinction crisis in the taxonomic group of cycads 下载免费PDF全文
Kowiyou Yessoufou Barnabas H. Daru Respinah Tafirei Hosam O. Elansary Isaac Rampedi 《Ecology and evolution》2017,7(8):2735-2746
Will the ongoing extinction crisis cause a severe loss of evolutionary information accumulated over millions of years on the tree of life? This question has been largely explored, particularly for vertebrates and angiosperms. However, no equivalent effort has been devoted to gymnosperms. Here, we address this question focusing on cycads, the gymnosperm group exhibiting the highest proportion of threatened species in the plant kingdom. We assembled the first complete phylogeny of cycads and assessed how species loss under three scenarios would impact the cycad tree of life. These scenarios are as follows: (1) All top 50% of evolutionarily distinct (ED ) species are lost; (2) all threatened species are lost; and (3) only all threatened species in each IUCN category are lost. Finally, we analyzed the biogeographical pattern of cycad diversity hotspots and tested for gaps in the current global conservation network. First, we showed that threatened species are not significantly clustered on the cycad tree of life. Second, we showed that the loss of all vulnerable or endangered species does not depart significantly from random loss. In contrast, the loss of all top 50% ED , all threatened or all critically endangered species, would result in a greater loss of PD (Phylogenetic Diversity) than expected. To inform conservation decisions, we defined five hotpots of diversity, and depending on the diversity metric used, these hotspots are located in Southern Africa, Australia, Indo‐Pacific, and Mexico and all are found within protected areas. We conclude that the phylogenetic diversity accumulated over millions of years in the cycad tree of life would not survive the current extinction crisis. As such, prioritizing efforts based on ED and concentrating efforts on critically endangered species particularly in southern Africa, Australia, Indo‐Pacific, and Mexico are required to safeguarding the evolutionary diversity in the cycad tree of life. 相似文献
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Thierry Allario Aude Tixier Hosam Awad Cedric Lemaire Nicole Brunel Eric Badel Têtè S. Barigah Jean‐Louis Julien Pierre Peyret Ewa J. Mellerowicz Herve Cochard Stephane Herbette 《Physiologia plantarum》2018,163(4):502-515
While the xylem hydraulic properties, such as vulnerability to cavitation (VC), are of paramount importance in drought resistance, their genetic determinants remain unexplored. There is evidence that pectins and their methylation pattern are involved, but the detail of their involvement and the corresponding genes need to be clarified. We analyzed the hydraulic properties of the 35S::PME1 transgenic aspen that ectopically under‐ or over‐express a xylem‐abundant pectin methyl esterase, PtxtPME1. We also produced and analyzed 4CL1::PGII transgenic poplars expressing a fungal polygalacturonase, AnPGII, under the control of the Ptxa4CL1 promoter that is active in the developing xylem after xylem cell expansion. Both the 35S::PME1 under‐ and over‐expressing aspen lines developed xylem with lower‐specific hydraulic conductivity and lower VC, while the 4CL1::PGII plants developed xylem with a higher VC. These xylem hydraulic changes were associated with modifications in xylem structure or in intervessel pit structure that can result in changes in mechanical behavior of the pit membrane. This study shows that homogalacturonans and their methylation pattern influence xylem hydraulic properties, through its effect on xylem cell expansion and on intervessel pit properties and it show a role for PtxtPME1 in the xylem hydraulic properties. 相似文献
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Improvement of Metabolic and Histological Changes of Adiposity in Rats by Synthetic Oleoyl Chalcones
Azza A. M. AlKhathami Hosam A. Saad Fareed A. Fareed Eman S. El-Shafey Eslam S. Elsherbiny Mamdouh R. El Nahas Mohamed R. E. Aly 《化学与生物多样性》2023,20(2):e202200670
We previously reported that synthetic oleoyl chalcones had a favorable effect to alleviate metabolic consequences of obesity in male SD rats. In this work, we prepared and characterized by spectroscopic tools, a set of six oleoyl chalcones ( 5a–c , 10 and 11a,b ). The comparative effects of the previously prepared oleoyl chalcones and their new synthetic analogs on metabolic and histological changes in obese male SD rats were studied. It was found that the oleoyl chalcones IIIa and IV were the best in improving many metabolic parameters, e. g., FBG, FI, ISI, TG, and total cholesterol. They cured systemic inflammation, through inhibition of the TNF-α and induction of adiponectin production. Moreover, chalcones IIIa and IV alleviated the oxidative stress accompanying obesity through the induction of the antioxidant enzymes GPX, SOD and CAT besides, GSH. Interestingly, chalcones IIIa and IV exerted hepatoprotective potency and ameliorated the manifestations of NAFLD via inhibition of apoptosis and induction of autophagy of hepatic cells. In conclusion, the oleoyl chalcones IIIa and IV were the most effective candidates among the series of synthetic chalcones in correcting body weight and the consequent metabolic and histological changes in adiposity. 相似文献
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Amal I. Linjawi Ahmed R. Afify Hosam A. Baeshen Dowen Birkhed Khalid H. Zawawi 《Saudi Journal of Biological Sciences》2021,28(1):280-285
BackgroundThe aim of this cross-sectional study was to compare the dimensions of mandibular symphysis (MS) between gender and the different sagittal and vertical skeletal relationships.Material and MethodsPre-treatment records of orthodontic patients were divided according to gender, sagittal (Class I, II and III) and vertical (decreased, average and increased mandibular plane [MP] angle) skeletal relationships. Measurements of MS parameters were performed on lateral cephalograms using IMAGEJ software. Comparisons between MS parameters and gender and the different skeletal relationships was performed using multifactorial and one-way ANOVA, and independent sample t-tests.ResultsA total of 104 records (25 males and 79 females) fulfilled the inclusion criteria. Males had significantly greater MS surface area, dentoalveolar length, skeletal symphysis length, total symphysis length, vertical symphysis dimension and symphysis convexity (p < 0.05). Skeletal Class II patients had significantly greater dentoalveolar and skeletal symphysis lengths while Class III had greater chin length, vertical symphysis dimension and symphysis convexity (p < 0.05). Patients with decreased vertical dimension had greater skeletal symphysis length (p = 0.026) and those with an average vertical relationship had greater chin length (p < 0.001).ConclusionsThe morphology of the mandibular symphysis is affected by gender, sagittal and vertical skeletal patterns. Males had increased mandibular symphysis surface area and linear dimensions. Class II patients had greater dentoalveolar length. Chin length was greater in patients with an average MP angle. 相似文献
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Hosam Ali Baeshen 《Saudi Journal of Biological Sciences》2021,28(1):1088
Extraneous activities of either the mouth, tongue or the jaw comprise the oral parafunctional habits of the stomatognathic system. This denominated habit is expressed through bruxism, digit sucking, nail biting to name a few, have led to hypothesizing the possible relationship of evolution of occluso-facial abnormalities such as malocclusion thereby hindering the conventional developmental process. Hence, the present study aimed to determine the prevalence and the possible relationship of parafunctional oral habits with the types of malocclusions among 12–16 years old females in Jeddah, Saudi Arabia. This cross-sectional study was conducted through questionnaire and clinical examinations, where the sagittal abnormalities within a randomly selected 672 participants who met the eligibility criteria were tabulated and analyzed. A positive history of the presence of parafunctional habit was recorded among all the participants with nasal and mouth breathing [46.6%], nail biting [39.6%] being predominant. 36.4% presented with significantly higher prevalence of bi-maxillary protrusion in mouth breathers while 17.1% with moderate overbite in participants with nail biting habit. Therefore, within the limitations of the present study, the findings do support the literature on the prevalence and the possible association of these habits with the malocclusion development thereby emphasizing on the importance of early recognition, management and prevention of them. 相似文献
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Khalid H. Zawawi Fahad F. Alsulaimani Ayman A. Al-Dharrab Ahmed R. Afify Mohammad S. Al-Zahrani Hosam A. Baeshen 《Saudi Journal of Biological Sciences》2021,28(6):3534-3539
AimsThis cross-sectional study compared and contrasted the morphological characteristics of Class I, II and III malocclusions in an adolescent Saudi population.MethodsAdolescent Saudis with Angle’s Class I, II and III malocclusions were selected from orthodontic patients’ records. Angular and linear measurements were compared between the three groups. Cephalometric analysis was performed using the VistadentOC® software. Multifactorial ANOVA for angular and linear measurements between and within groups.ResultsOrthodontic records of 300 patients were included. There was no significant difference between and within groups in age and distribution of Angle’s classification, p > 0.05. Multifactorial ANOVA showed that there were significant interactions between gender and malocclusions in skeletal, dental and soft tissue measurements, p < 0.05. There were significant differences in the sagittal and vertical skeletal measurements between groups, p < 0.05. The dental measurements were also significantly different in most of the measurements (p < 0.05). Moreover, there were significantly different readings among the groups in the soft tissue analysis.ConclusionMorphological characteristics of adolescent Saudis show unique differences between gender and malocclusions, more so in Class III malocclusions. Class II and III malocclusions also show skeletal differences amongst the groups. 相似文献
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Hosam Elsaied Hatch W Stokes Keiko Kitamura Yasurou Kurusu Yoichi Kamagata Akihiko Maruyama 《The ISME journal》2011,5(7):1162-1177
In order to understand the structure and biological significance of integrons and associated gene cassettes in marine polluted sediments, metagenomic DNAs were extracted from sites at Suez and Tokyo Bays. PCR amplicons containing new integrase genes, intI, linked with novel gene cassettes, were recovered and had sizes from 1.8 to 2.5 kb. This approach uncovered, for the first time, the structure and diversity of both marine integron attachment site, attI, and the first gene cassette, the most efficiently expressed integron-associated gene cassette. The recovered 13 and 20 intI phylotypes, from Suez and Tokyo Bay samples, respectively, showed a highly divergence, suggesting a difference in integron composition between the sampling sites. Some intI phylotypes showed similarity with that from Geobacter metallireducens, belonging to Deltaproteobacteria, the dominant class in both sampling sites, as determined by 16S rRNA gene analysis. Thirty distinct families of putative attI site, as determined by the presence of an attI-like simple site, were recovered. A total of 146 and 68 gene cassettes represented Suez and Tokyo Bay unsaturated cassette pools, respectively. Gene cassettes, including a first cassette, from both sampling sites encoded two novel families of glyoxalase/bleomycin antibiotic-resistance protein. Gene cassettes from Suez Bay encoded proteins similar to haloacid dehalogenases, protein disulfide isomerases and death-on-curing and plasmid maintenance system killer proteins. First gene cassettes from Tokyo Bay encoded a xenobiotic-degrading protein, cardiolipin synthetase, esterase and WD40-like β propeller protein. Many of the first gene cassettes encoded proteins with no ascribable function but some of them were duplicated and possessed signal functional sites, suggesting efficient adaptive functions to their bacterial sources. Thus, each sampling site had a specific profile of integrons and cassette types consistent with the hypothesis that the environment shapes the genome. 相似文献
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Muhammad Asif Rasheed Muhammad Awais Adil Aldhahrani Fayez Althobaiti Alaa Alhazmi Sobia Sattar Umara Afzal Hosam Ali Baeshen Hesham Ali El Enshasy Daniel Joe Dailin Ameena A. AL-surhanee Faryal Kabir 《Saudi Journal of Biological Sciences》2021,28(9):4859-4866
ObjectiveSerious non-gastrointestinal-tract infections and food poisoning are caused by Bacillus cereus. Vaccination against B. cereus is very important. The aim of this study was to identify and analyze B and T cell epitopes for chromate transporter protein of the bacteria.MethodsMultiple sequence alignment with the Clustal Omega method was used to identify conserved regions and Geneious Prime was used to produce a consensus sequence. T and B cell epitopes were predicted by various computational tools from the NetCTL and Immune Epitope Database (IEDB), respectively.ResultsAltogether, 6 HTL cells and 11 CTL epitopes were predicted. This vaccine's molecular docking is done with Patch Dock and LigPlot to verify interactions. The immune server (C-IMMSIM) was used to develop In silico immune response in order to assess the multi-epitope vaccine's immunogenic profile.ConclusionWe designed universal vaccine against B. cereus responsible for food poisoning. The disease may be avoided with the aid of the proposed epitope-based vaccine. 相似文献