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151.
Xiuting Li U. S Dinish Juan Aguirre Renzhe Bi Kapil Dev Amalina Binte Ebrahim Attia Suhanyaa Nitkunanantharajah Qian Han Lim Mathias Schwarz Yik Weng Yew Steven Tien Guan Thng Vasilis Ntziachristos Malini Olivo 《Journal of biophotonics》2019,12(9)
Raster Scanning Optoacoustic Mesoscopy (RSOM) is a novel optoacoustic imaging modality that offers non‐invasive, label‐free, high resolution (~7 μm axial, ~30 μm lateral) imaging up to 1 to 2 mm below the skin, providing novel quantitative insights into skin pathophysiology. As the RSOM image contrast mechanism is based on light absorption, it is expected that the amount of melanin present in the skin will affect RSOM images. However, the effect of skin tone in the performance of RSOM has not been addressed so far. Herein, we present the efficiency of RSOM for in vivo skin imaging of human subjects with Fitzpatrick (FP) skin types between II to V. RSOM images acquired from the volar forearms of the subjects were used to derive metrics used in RSOM studies, such as total blood volume, vessel diameter and melanin signal intensity. Our study shows that the melanin signal intensity derived from the RSOM images exhibited an excellent correlation with that obtained from a clinical colorimeter for the subjects of varying FP skin types. We could successfully estimate the vessel diameter at different depths of the dermis. Furthermore, our study shows that there is a need to compensate for total blood volume calculated for subjects with higher FP skin types due to the lower signal‐to‐noise ratio in dermis, owing to strong absorption of light by melanin. This study sheds light into how RSOM can be used for studying various skin conditions in populations with different skin phenotypes. 相似文献
152.
Ebrahim Shokoohi Hadi Panahi Hendrika Fourie Joaquín Abolafia 《Journal of nematology》2015,47(4):370-380
A population of Butlerius butleri
Goodey, 1929 was isolated from vermicompost in Kerman in the Kerman Province of Iran during a nematode survey that was conducted during 2014. This population of B. butleri is characterized by the presence of a dorsal thorn-like tooth (4 to 5 μm long), long spicules (44 to 47 μm long), gubernaculum (33 to 37 μm or more than half of the spicule length), three pairs of precloacal papillae, five pairs of postcloacal papillae (papillae V3 and V5 comprising three small papillae), and a long filiform tail (304 to 409 μm in females, 312 to 380 μm in males). Molecular and phylogenetic analysis of B. butleri individuals from this Iranian population based on 18S ribosomal deoxyribonucleic acid (rDNA) sequence placed this species close to Pseudodiplogasteroides compositus () and an unidentified Pseudodiplogasteroides species ( AB597237). Measurements, illustrations, and the phylogenetic tree, including the position of B. butleri are provided. AB597238相似文献
153.
Hossein Mahmoudvand Fatemeh Ezzatkhah Fariba Sharififar Iraj Sharifi Ebrahim Saedi Dezaki 《The Korean journal of parasitology》2015,53(1):21-27
Plants used for traditional medicine contain a wide range of substances that can be used to treat various diseases such as infectious diseases. The present study was designed to evaluate the antileishmanial effects of the essential oil and methanolic extract of Myrtus communis against Leishmania tropica on an in vitro model. Antileishmanial effects of essential oil and methanolic extract of M. communis on promastigote forms and their cytotoxic activities against J774 cells were evaluated using MTT assay for 72 hr. In addition, their leishmanicidal activity against amastigote forms was determined in a macrophage model, for 72 hr. Findings showed that the main components of essential oil were α-pinene (24.7%), 1,8-cineole (19.6%), and linalool (12.6%). Findings demonstrated that M. communis, particularly its essential oil, significantly (P<0.05) inhibited the growth rate of promastigote and amastigote forms of L. tropica based on a dose-dependent response. The IC50 values for essential oil and methanolic extract was 8.4 and 28.9 μg/ml against promastigotes, respectively. These values were 11.6 and 40.8 μg/ml against amastigote forms, respectively. Glucantime as control drug also revealed IC50 values of 88.3 and 44.6 μg/ml for promastigotes and amastigotes of L. tropica, respectively. The in vitro assay demonstrated no significant cytotoxicity in J774 cells. However, essential oil indicated a more cytotoxic effect as compared with the methanolic extract of M. communis. The findings of the present study demonstrated that M. communis might be a natural source for production of a new leishmanicidal agent. 相似文献
154.
155.
Mahbube Arabbeigi Ahmad Arzani Mohamad Mahdi Majidi Razie Kiani Badraldin Ebrahim Sayed Tabatabaei Farshad Habibi 《Acta Physiologiae Plantarum》2014,36(8):2243-2251
Uremia Salt Lake, in North West Iran, has a hyper-saline water. A rare highly salinity-tolerant grass species, Aegilops cylindrica grows along its shores. Salinity tolerance of 44 genotypes of Ae. cylindrica, mainly collected from the Lake, was evaluated under control and 400 mM NaCl conditions using the physiological traits of plant height, dry weight, proline content, Na+ and K+ concentrations as well as K+/Na+ ratio. To evaluate the association between microsatellite (EST-SSR and SSR) markers and salinity tolerance, 35 primer pairs were used. Results showed a significant variation in the 44 genotypes studied in terms of their traits except for proline content. Ten most salinity-tolerant genotypes were identified based on their ability to survive, to produce the highest dry weight, and to sustain the least leaf Na+ concentration under salinity stress. The very high negative correlation found between Na+ concentration and salinity tolerance revealed the importance of individual or a combination of Na+ exclusion and excretion mechanisms contributing to the hyper-salinity tolerance of these genotypes. Clustering analysis based on marker data divided the 44 studied genotypes into two groups that were consistent with their saline and non-saline geographical areas. Results of molecular markers showed that four microsatellite markers (Xgwm312, Xwmc170, Xgwm291 and Xgwm410) generated a distinguished banding pattern in ten most salinity-tolerant genotypes. These results supported previous reports on their linkage with Na+ exclusion genes (HKT1;5 and HKT1;4) in wheat, which provided further evidence of usefulness of both genes and the linked markers to the salinity tolerance of the halophytic grass family species. 相似文献
156.
Martin Dragosits Stefan Pflügl Simone Kurz Ebrahim Razzazi-Fazeli Iain B. H. Wilson Dubravko Rendic 《Applied microbiology and biotechnology》2014,98(8):3553-3567
Galactosidases are widespread enzymes that are used for manifold applications, including production of prebiotics, biosynthesis of different transgalactosylated products, improving lactose tolerance and in various analytical approaches. The nature of these applications often require galactosidases to be present in a purified form with clearly defined properties, including precisely determined substrate specificities, low sensitivity to inhibitors, and high efficiency and stability under distinct conditions. In this study, we present the recombinant expression and purification of two previously uncharacterized β-galactosidases from Aspergillus nidulans as well as one β-galactosidase from Aspergillus niger. All enzymes were active toward p-nitrophenyl-β-d-galactopyranoside as substrate and displayed similar temperature and pH optima. The purified recombinant galactosidases digested various complex substrates containing terminal galactose β-1,4 linked to either N-acetylglucosamine or fucose, such as N-glycans derived from bovine fibrin and Caenorhabditis elegans. In our comparative study of the recombinant galactosidases with the commercially available galactosidase from Aspergillus oryzae, all enzymes also displayed various degrees of activity toward complex oligosaccharides containing β-1,3-linked terminal galactose residues. All recombinant enzymes were found to be robust in the presence of various organic solvents, temperature variations, and freeze/thaw cycles and were also tested for their ability to synthesize galactooligosaccharides. Furthermore, the use of fermentors considerably increased the yield of recombinant galactosidases. Taken together, we demonstrate that purified recombinant galactosidases from A. niger and from A. nidulans are suitable for various glycobiological and biotechnological applications. 相似文献
157.
Anion Effect on the Binary and Ternary Phase Diagrams of Chiral Medetomidine Salts and Conglomerate Crystal Formation 下载免费PDF全文
The binary phase diagrams of hydrogen halides salts of medetomidine (Med.HX, X:Br,I) and hydrogen oxalate salt of medetomidine (Med.Ox) were determined based on thermogravimetric/differential thermal analysis (TGA/DTA) and their crystal structure behavior was confirmed by comparison of the X‐ray diffractometry and FT‐IR spectroscopy of the racemate and pure enantiomer. All hydrogen halide salts presented racemic compound behavior. Heat of fusion of halides salt of (rac)‐medetomidine decreased with ionic radius increase. Eutectic points for Med.HCl (previously reported), Med.HBr, and Med.HI rest were unchanged approximately. The solubility of different enantiomeric mixtures of Med.HBr and Med.HI were measured at 10, 20, and 30°C in 2‐propanol showing a solubility increase with ionic radius. A binary phase diagram of Med.Ox shows a racemic conglomerate behavior. The solubility of enantiomeric mixtures of Med.Ox were measured at 10, 20, 30, and 40°C. The ternary phase diagram of Med.Ox in ethanol conforms to a conglomerate crystal forming system, favoring its enantiomeric purification by preferential crystallization. Chirality 26:183–188, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
158.
159.
Jasmine Fledderjohann Sutapa Agrawal Sukumar Vellakkal Sanjay Basu Oona Campbell Pat Doyle Shah Ebrahim David Stuckler 《PloS one》2014,9(9)
Background
India is the only nation where girls have greater risks of under-5 mortality than boys. We test whether female disadvantage in breastfeeding and food allocation accounts for gender disparities in mortality.Methods and Findings
Secondary, publicly available anonymized and de-identified data were used; no ethics committee review was required. Multivariate regression and Cox models were performed using Round 3 of India’s National Family and Health Survey (2005–2006; response rate = 93.5%). Models were disaggregated by birth order and sibling gender, and adjusted for maternal age, education, and fixed effects, urban residence, household deprivation, and other sociodemographics. Mothers’ reported practices of WHO/UNICEF recommendations for breastfeeding initiation, exclusivity, and total duration (ages 0–59 months), children’s consumption of 24 food items (6–59 months), and child survival (0–59 months) were examined for first- and secondborns (n = 20,395). Girls were breastfed on average for 0.45 months less than boys (95% CI: = 0.15 months to 0.75 months, p = 0.004). There were no gender differences in breastfeeding initiation (OR = 1.04, 95% CI: 0.97 to 1.12) or exclusivity (OR = 1.06, 95% CI: 0.99 to 1.14). Differences in breastfeeding cessation emerged between 12 and 36 months in secondborn females. Compared with boys, girls had lower consumption of fresh milk by 14% (95% CI: 79% to 94%, p = 0.001) and breast milk by 21% (95% CI: 70% to 90%, p<0.000). Each additional month of breastfeeding was associated with a 24% lower risk of mortality (OR = 0.76, 95% CI: 0.73 to 0.79, p<0.000). Girls’ shorter breastfeeding duration accounted for an 11% increased probability of dying before age 5, accounting for about 50% of their survival disadvantage compared with other low-income countries.Conclusions
Indian girls are breastfed for shorter periods than boys and consume less milk. Future research should investigate the role of additional factors driving India’s female survival disadvantage. 相似文献160.
Diverse tree structures such as blood vessels, branches of a tree and river basins exist in nature. The constructal law states that the evolution of flow structures in nature has a tendency to facilitate flow. This study suggests a theoretical basis for evaluation of flow facilitation within vascular structure from the perspective of evolution. A novel evolution parameter (Ev) is proposed to quantify the flow capacity of vascular structures. Ev is defined as the ratio of the flow conductance of an evolving structure (configuration with imperfection) to the flow conductance of structure with least imperfection. Attaining higher Ev enables the structure to expedite flow circulation with less energy dissipation. For both Newtonian and non-Newtonian fluids, the evolution parameter was developed as a function of geometrical shape factors in laminar and turbulent fully developed flows. It was found that the non-Newtonian or Newtonian behavior of fluid as well as flow behavior such as laminar or turbulent behavior affects the evolution parameter. Using measured vascular morphometric data of various organs and species, the evolution parameter was calculated. The evolution parameter of the tree structures in biological systems was found to be in the range of 0.95 to 1. The conclusion is that various organs in various species have high capacity to facilitate flow within their respective vascular structures. 相似文献