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Molecular and cellular mechanisms of neuroprotection by oligopeptides from snake venoms

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BIOCELL 2024年第6期48卷 897-904页

作者： CARLOS ALBERTO-SILVA brenda RUFINO dA SILVA Natural and Humanities Sciences Center Experimental Morphophysiology LaboratoryFederal University of ABC(UFABC)São Bernardo do CampoSão PauloBrazil

Venom snake-derived peptides have multiple biochemical,pharmacological,and toxicological proﬁles,allowing for the discovery of new medicinal products and therapeutic *** review speciﬁcally examines the fundamental elements of neuroprotection offered by different oligopeptides derived from snake *** also includes a brief evaluation of short peptides that are being considered as potential therapeutic ***-rich peptides and tryptophyllin family peptides isolated from the crude venom of Viperidae family snakes,speciﬁcally Bothrops atrox,Bothrops jararaca,and Bothrops moojeni,have been shown to have pro-survival properties,the ability to reduce oxidative stress,and the ability to promote cell viability and mitochondrial *** signiﬁcant mechanisms are related to the neuroprotection mediated by snake venom oligopeptides:(1)Activation of the L-arginine metabolite pathway,such as polyamines from ornithine metabolism,which reduces N-methyl-d-aspartate(NMdA)-type glutamate receptor activity;(2)Enhancement of cell viability by activating the nerve growth factor-signaling pathway;and(3)Activation of the Muscarinic acetylcholine receptor subtype M1(mAChR-M1).These small peptides show promise as neuroprotective agents against a variety of neurodegenerative disorders.

关键词： Neuroprotective peptides Neurodegenerative disease Oxidative stress Reactive oxygen species Biopeptides

Colon Adenocarcinoma in a Retrograde Intussusception: A Case Report and Literature Review

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Open Journal of Gastroenterology 2024年第5期14卷 153-160页

作者： Carlos Hernández Brito Pedro Arredondo Ruiz brenda Paola Sáenz dávila Arsenio Torres delgado Luis Eduardo Méndez Turrubiates Luis Ángel Amezcua Toledo Omar Josué Herrera López Surgical Oncology department Centro Oncol&#243gico Onkolid Veracruz Mexico Clinical Oncology department Centro Oncol&#243gico Onkolid Veracruz Mexico General and Laparoscopic Surgery Corporativo M&#233dico-Quir&#250rgico Torres Veracruz Mexico Radiation Oncology department Centro Oncol&#243gico Onkolid Veracruz Mexico Radiology department Centro Oncol&#243gico Onkolid Veracruz Mexico Anatomical Pathology department Centro Oncol&#243gico Onkolid Veracruz Mexico

Background: Intussusception is defined as a telescoping of a proximal gastrointestinal segment with its mesentery to a distal one, only 5% occur in adults and in colon the probability that it is caused by a malignant disease is up to 65%. Only 1% occurs in a retrograde manner, the rest occur in an anterograde manner. Aim: describe the clinical presentation of an intussusception in the adult patient as well as its most frequent causes and possible complications that influence decision making for a definitive treatment. Case Presentation: A 66-year-old woman diagnosed with colon adenocarcinoma who underwent elective transverse colectomy and colonic anastomosis with an incidental finding of a transverse colon tumor in a retrograde intussusception was studied. Conclusion: In any adult patient with an intussusception especially in colon a neoplasia should be suspected and the affected segment should be resected without being reduced due to the risk of perforation and tumor dissemination.

关键词： Colon Cancer Colon Adenocarcinoma Colonic Intussusception Intussusception

What are extreme environmental conditions and how do organisms cope with them？

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Current Zoology 2011年第3期57卷 363-374页

作者： John C. wingfield J. Patrick KELLEY Frederic ANGELIER department of Neurobiology Physiology and Behavior University of California One Shields Avenue Davis CA 95616 U.S.A

Severe environmental conditions affect organisms in two major ways. The environment may be predictably severe such as in deserts, polar and alpine regions, or individuals may be exposed to temporarily extreme conditions through weather, presence of predators, lack of food, social status etc. Existence in an extreme environment may be possible, but then to breed or molt in addition can present major bottlenecks that have resulted in the evolution of hormone-behavior adaptations to cope with unpredictable events. Examples of hormone-behavior adaptations in extreme conditions include attenuated testosterone secretion because territoriality and excess courtship may be too costly when there is one opportunity to reproduce. The individual may even become insensitive to testosterone when target areas of the brain regulating reproductive behavior no longer respond to the hormone. A second example is reduced sensitivity to glucocorticoids following acute stress during the breeding season or molt that allows successful reproduction and/or a vital renewal of the integument to endure extreme conditions during the rest of the year. Reduced sensitivity could involve：（a） modulated response of the hypothalamo-pituitary-adrenal axis, （b） reduced sensitivity to high glucocorticoid levels, or （c） a combination of （a） and （b）. Moreover, corticosteroid binding proteins （CBP） buffer responses to stress by reducing the movement of glucocorticoids into target cells. Finally, intracellular enzymes （11 β-hydroxysteroid dehydrogenase and variants） can deactivate glucocorticoids entering cells thus reducing interaction with receptors. These mechanisms have important implications for climate change and increasing extremes of weather [Current Zoology 57 （3）： 363-374, 2011].

关键词： Extreme environment Habitat configuration Glucocorticoids Stress response Corticosteroid-binding proteins Behavior

Unusual reaction of a tungsten alkylidyne complex with ***,characterization,and crystal structures of oxo trimers

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Science China Chemistry 2011年第12期54卷 1903-1908页

作者： dOUGAN brenda A. department of Chemistry University of Tennessee

The reaction of the alkyl alkylidyne W（CH2CMe3）3（=CSiMe3）（1） with H20 in THF and with d20 in benzene-d6 gave two new trimeric oxo complexes： W3O3（μ=O）3（CH2CMe3）6（THF）3 （2） and [W303（μ=O）3（Ch2CMe3）6（d2O）3] 2benzene-d6 （3.2benzened6）, respectively, each containing two alkyl ligands per W atom. This is in contrast to the dimer W2o（β-O）（CH2CMe3）6, containing three alkyl ligands per W atom, from the previously reported reaction of the alkyl alkylidyne analog W（CH2CMe3）3- （=-CCMe3） with H2O. In the reaction of 1 with d20 in THF, an unstable intermediate W2O2（μ-O）（Cd2SiMe3）2（CH2CMe3）4 （4-d4） was identified. Kinetic studies of the reactions of 1 with excess H2O and d2O in THF-ds, yielding 4 and 4-d4, respectively, give a kinetic isotope effect （KIE） of 3.46（3） at 298（1） K, suggesting that the disappearance of 1 is a rate-determining step.

关键词： alkylidyne water oxo complexes kinetic isotope effect

Kinetic and thermodynamic studies on partitioning of polychlorinated biphenyls (PCBs) between aqueous solution and modeled individual soil particle grain sizes

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Journal of Environmental Sciences 2019年第2期31卷 100-110页

作者： Gbadebo Clement Adeyinka brenda Moodley School of Chemistry and Physics College of AgricultureEngineering and SciencesUniversity of KwaZulu-Natal

The significance of soil mineral properties and secondary environmental conditions such as pH, temperature, ionic strength and time in the partitioning of eight selected polychlorinated biphenyl(PCB) congeners between aqueous solution and soil particles with different grain sizes was studied. The mineral properties of a model soil sample were determined, and Brunauer–Emmett–Teller(BET) adsorption–desorption isotherms were employed to observe the surface characteristics of the individual modeled soil *** adsorption experiments were conducted to determine the sorption of PCBs onto soil particles of different sizes. The results revealed that the sorption of PCB congeners onto the soil was dependent on the amount of soil organic matter, surface area, and pore size distribution of the various individual soil particles. Low pH favored the sorption of PCBs,with maximum sorption occurring between pH 6.5 and 7.5 with an equilibration period of 8 *** in the ionic strength were found to be less significant. Low temperature favored the sorption of PCBs onto the soil compared to high temperatures. Thermodynamic studies showed that the partition coefficient(K_d) decreased with increasing temperature, and negative and low values of ΔH° indicated an exothermic physisorption process. The data generated is critical and will help in further understanding remediation and cleanup strategies for polluted water.

关键词： Partitioning PCBs Soil particle grain sizes Kinetics Thermodynamic studies pH

Visual field defects and retinal nerve fiber layer damage in buried optic disc drusen: a new insight

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International Journal of Ophthalmology(English edition) 2022年第10期15卷 1641-1649页

作者： brenda Nana Wandji Artémise dugauquier Adèle Ehongo Faculty of Medicine UniversitéLibre de BruxellesBrussels 1070Belgium department of Ophthalmology Erasme HospitalBrussels 1070Belgium

AIM: To assess the association between buried optic disc drusen(BOdd) location using spectral-domain optical coherence tomography(Sd-OCT) and the location of associated visual field defects(VFd) using the Garway-Heath ***: This monocentric retrospective crosssectional study was led at the authors’ institution. Adult patients diagnosed with BOdd who had complete records with a reliable Humphrey? 24-2 visual field, macular, and papillary OCT were enrolled. Fisher’s exact test was used to measure the association between BOdd location and VFd distribution according to Garway-Heath’s ***: Totally 20 eyes of 15 patients were included(60% females). The median age(interquartile range) was 63(43)y and the median best corrected visual acuity(BCVA) was-0.08(0.08) log MAR. BOdd were mostly located in zones A, E, and F. The minimal rim width(MRW) was globally preserved. The retinal nerve fiber layer(RNFL) was predominantly altered in zones d, E, and F. There was a significant correlation between BOdd location and that of RNFL alterations in zones d(P=0.03) and E(P=0.025);Moreover, the presence of BOdd in the E zone was significantly related to damaged RNFL in the neighbouring sectors d and F(P=0.012;P=0.02 respectively). Sixty-three percent(12/19) of visual fields were abnormal and there was a significant match(Phi=0.7, P=0.009) between drusen location and VFd only in zone ***: BOdd do not only affect young patients and can be more harmful than usually expected, as we found VFd in 63% of cases. There is a correspondence between BOdd location, RNFL damage, and VFd distributions. The presence of BOdd induces the overestimation of MRW,thereby disrupting its sensitivity as an early indicator of ganglion fibers damage.

关键词： buried optic disc drusen visual field spectral-domain optical coherence tomography Garway-Heath mapping retinal nerve fiber layer

3d printing of ABS *** of processing and effects of multi-wall and single-wall carbon nanotubes on thermal,mechanical and electrical properties

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Journal of Materials Science & Technology 2022年第26期121卷 52-66页

作者： Sithiprumnea dul brenda J.Alonso Gutierrez Alessandro Pegoretti Jaime Alvarez-Quintana Luca Fambri department of Industrial Engineering and INSTM Research Unit University of TrentoTrento 38123Italy Centro de Investigación en Materiales Avanzados S.C.Unidad MonterreyApodaca 66600Mexico Facultad de Ingeniería Mecánica y Eléctrica Universidad Autónoma de Nuevo LeónAvenida Universidad s/nCiudad UniversitariaSan Nicolás de los Garza 66451México

The following paper reports on a comparative study of the effects of two types of carbon nanotubes,namely multiwall(MWCNT)and single-wall(SWCNT)carbon nanotube,on the properties of 3d-printed parts produced with acrylonitrile-butadiene-styrene(ABS)nanocomposites with various CNT loadings of5-10 wt.%.Quasi-static tensile properties and Vicat softening temperature of 3d-printed parts were enhanced with the increasing CNT *** highest enhancement in tensile properties was observed for the ABS/CNT nanocomposites at 10 wt.%filler loading.3d-printed ABS/SWCNT composites showed higher tensile modulus,better creep stability and higher Vicat ***,the strength of ABS/SWCNT 3d samples is relatively lower than that of ABS/*** addition,3d-printed parts exhibited anisotropic electrical conductive behaviour,which has a conductivity of through-layer of about2-3 orders of magnitude higher than *** highest conductivity of 3d-printed samples reached25.2 S/m,and 9.3 S/m for ABS/MWCNT and ABS/SWCNT composites at 10 wt.%,*** results obtained,*** successful fuse filament fabrication and the consequent electromechanical properties,confirm that these 3d printable nanocomposite could be properly utilized for the production,and application up to about 90°C,of thermoelectric devices and/or resistors for flexible circuits.

关键词： Fuse filament fabrication Conductive polymers Nanocomposites Mechanical properties Creep behavior Resistivity

Towards informed metrics for examining the role of human-induced animal responses in tag studies on wild animals

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Integrative Zoology 2019年第1期14卷 17-29页

作者： Rory P.WILSON Mark HOLTON Vianney LWILSON Richard GUNNER brenda TYSSE Gwendoline IWILSON Flavio QUINTANA Carlos dUARTE d.Michael SCANTLEBURY Biosciences Swansea UniversitySingleton ParkSwanseaWalesUK department of Geography Swansea UniversitySingleton ParkSwanseaWalesUK Instituto de Biología de Organismos Marinos(IBIOMAR) CONICETPuerto MadrynChubutArgentina Red Sea Research Centre King Abdullah University of Science and TechnologyThuwalSaudi Arabia School of Biological Sciences Institute for Global Food SecurityQueen’s University BelfastBelfastUK

Two prime issues can detrimentally affect animals that have been equipped with tags:(i)the effect of the cap-ture and restraint process;and(ii)the effect of the tag *** work examines some of the issues surround-ing quantification of tag effects on wild animals for both restrained and free-living animals.A new method to quantify stress effects based on monitoring ventilation rates in relation to activity is suggested for restrained an-imals which may help improve the practice of handling *** is also suggested that various metrics,many derived from accelerometers,can be examined in tagged wild animals to examine the change in behaviors over time with a view to having a better understanding of welfare issues,assuring the quality of recorded data and in-forming best practice.

关键词： behavior stress tags wild animals

Coping with extremes:convergences of habitat use,territoriality,and diet in summer but divergences in winter between two sympatric snow finches on the Qinghai-Tibet Plateau

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Integrative Zoology 2020年第6期15卷 533-543页

作者： dongming LI Jason E.dAVIS Yanfeng SUN Gang WANG Ghulam NABI John C.wingfield Fumin LEI Key Laboratory of Animal Physiology Biochemistry and Molecular Biology of Hebei ProvinceCollege of Life SciencesHebei Normal UniversityShijiazhuangHebei ProvinceChina Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijingChina department of Neurobiology Physiology and BehaviorUniversity of CaliforniaDavisCaliforniaUSA department of Biology Radford UniversityRadfordVirginiaUSA Ocean College Hebei Agricultural UniversityQinhuangdaoHebei ProvinceChina University of Chinese Academy of Sciences BeijingChina Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingChina

On the Qinghai-Tibet Plateau,extreme environmental conditions have imposed intense selective pressure on the evolution of phenotypic traits of wild *** date,limited information is available on behavioral and ecological traits concerning niche differentiation among sympatric animals on the Qinghai-Tibet Plateau,especially during winter when the environments are most ***,we studied the seasonal variations in habitat occurrence,territorial behavior,and diet in two sympatric snow finches(the white-rumped snow finch,Onychostruthus taczanowskii,WRSF;and the rufous-necked snow finch,Pyrgilauda ruficollis,RNSF)to determine convergence and divergence of ecological traits in such severe climatic *** results showed that:(i)WRSF occupied rural areas as a dominant species throughout the annual cycle while RNSF occupied the rural areas in summer and then shifted to human-occupied areas in winter and spring;(ii)WRSFs exhibited robust aggressive behavior and territoriality during winter relative to RNSFs;(iii)the diets of both species varied with the season but did not vary between species except that WRSF ate significantly more seeds but RNSF consumed more starchy material derived from human food waste during ***,the separations in the spatial niche and territoriality between WRSF and RNSF,especially in winter,may contribute to alleviating the pressure of interspecific competition,and promoting the coexistence of the two sympatric snow finches in the extreme environments on the Qinghai-Tibet Plateau.

关键词： diet habitat use Qinghai-Tibet Plateau snow finch territorial behavior