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The eye and wing morphology of Drosophila melanogaster maintain unique, stable pattern of genesis from larval eye and wing imaginal discs. Increased apoptosis in cells of eye and wing discs was found to be associated with flubendiamide (fluoride containing insecticide) exposure (at the range 0.25–10 μg/mL) in D. melanogaster larvae. The chemical fed larvae on attaining adulthood revealed alterations in morphology and symmetry of their compound eyes and wings through scanning electron microscopy. Nearly 40% and 30% of flies (P generation) demonstrated alterations in eyes and wings respectively. Transmission electron microscopic study (at the range 1–20 μg/mL) also established variation in the rhabdomere and pigment cell orientation as well as in the shape of the ommatidium. Subsequent SEM study with F1 and F2 generation flies also revealed structural variation in eye and wing. Decrease in percentage of altered eye and wing phenotype was noted in subsequent generations (P> F1 > F2). Thus, the diamide insecticide, flubendiamide, expected to be environmentally safe at sub-lethal concentrations was found to increase apoptosis in larvae and thereby cause morphological alteration in the adult D. melanogaster. This study further demonstrated trans-generational transmission of altered phenotype in three subsequent generations of a non-target insect model, D. melanogaster. 相似文献
23.
C. Mohandass A. S. Vijayaraj R. Rajasabapathy S. Satheeshbabu S. V. Rao C. Shiva I. De-Mello 《Indian journal of pharmaceutical sciences》2013,75(5):606-610
Seaweed extracts of Sargassum cinereum was used as a reducing agent in the eco-friendly extracellular synthesis of silver nanoparticles from an aqueous solution of silver nitrate (AgNO3). High conversion of silver ions to silver nanoparticles was achieved with a reaction temperature of 100° and a seaweed extract concentration of 10% with a residential time of 3 h. Formation of silver nanoparticles was characterised by spectrophotometry and the scanning electron microscope. The average particles size was ranging from 45 to 76 nm. Antimicrobial activities indicate the minimum inhibitory concentration of biologically synthesised nanoparticles tested against the pathogen Staphylococcus aureus with 2.5 μl (25 μg/disc). High inhibitions over the growth of Enterobacter aerogenes, Salmonella typhi and Proteus vulgaris were witnessed against the concentrations of 100 μg/disc. Promising potential and the future prospects of S. cinereum nanoparticles in pharmaceutical research are the highlights in this paper. 相似文献
24.
Robert J. Hopkins Nancy F. Daczkowski Paulina E. Kaptur Derek Muse Eric Sheldon Craig LaForce Suha Sari Thomas L. Rudge Edward Bernton 《Vaccine》2013
A new anthrax vaccine that could accelerate the immune response and possibly reduce the number of injections needed for protection would be desirable in a post-exposure setting. 相似文献
25.
Natalie Leow BDSc Paul Abbott BDSc MDS FRACDS Jacqueline Castro Salgado Odont Spec Endo Laura Firth BSc 《Australian endodontic journal : the journal of the Australian Society of Endodontology Inc》2012,38(3):107-112
Various methods are used to evaluate irrigants. The primary aim was to develop a model for preliminary testing of potential irrigants. The second aim was to investigate the effect of bicarbonate soda on smear layer by comparing it with ethylenediamine tetraacetic acid with cetrimide (EDTAC) and sodium hypochlorite (NaOCl). Extracted human single‐canal teeth were halved, and a uniform filing method was used to create smear layer. The following solutions were then applied – distilled water (control), 1% NaOCl, 17% EDTAC and bicarbonate soda at concentrations of 1%, 5%, 10% and 15%. Some samples had multiple solutions in different sequences. Samples were examined by scanning electron microscopy. Representative images were scored based on the degree of smear layer remaining. Results were analysed with the SAS system, using the GENMOD procedure. Complete smear layer was found in samples treated with all solutions except EDTAC used alone. There were no significant differences between the sequences, EDTAC/NaOCl/EDTAC and NaOCl/EDTAC/NaOCl. There were no significant differences between groups with and without bicarbonate soda. In conclusion, the model was effective for testing chemical effects on solutions on smear layer. Bicarbonate soda did not remove smear layer and provided no additional cleaning effects after EDTAC and NaOCl. 相似文献
26.
Agustín Ibá?ez Jaume Aguado Sandra Baez David Huepe Vladimir Lopez Rodrigo Ortega Mariano Sigman Ezequiel Mikulan Alicia Lischinsky Fernando Torrente Marcelo Cetkovich Teresa Torralva Tristan Bekinschtein Facundo Manes 《Social cognitive and affective neuroscience》2014,9(7):939-950
It is commonly assumed that early emotional signals provide relevant information for social cognition tasks. The goal of this study was to test the association between (a) cortical markers of face emotional processing and (b) social-cognitive measures, and also to build a model which can predict this association (a and b) in healthy volunteers as well as in different groups of psychiatric patients. Thus, we investigated the early cortical processing of emotional stimuli (N170, using a face and word valence task) and their relationship with the social-cognitive profiles (SCPs, indexed by measures of theory of mind, fluid intelligence, speed processing and executive functions). Group comparisons and individual differences were assessed among schizophrenia (SCZ) patients and their relatives, individuals with attention deficit hyperactivity disorder (ADHD), individuals with euthymic bipolar disorder (BD) and healthy participants (educational level, handedness, age and gender matched). Our results provide evidence of emotional N170 impairments in the affected groups (SCZ and relatives, ADHD and BD) as well as subtle group differences. Importantly, cortical processing of emotional stimuli predicted the SCP, as evidenced by a structural equation model analysis. This is the first study to report an association model of brain markers of emotional processing and SCP. 相似文献
27.
28.
《Vaccine》2015,33(27):3142-3149
To overcome the limiting antigenic repertoire of protein sub-units and the side effects of adjuvants applied in second generation vaccines, the present work combined in vitro and in vivo manipulations to develop biomaterials allowing natural antigen-loading and presentation in vitro and further activation of the immune response in vivo. 3-dimensional laser micro-textured implantable Si-scaffolds supported mouse macrophage adherence, allowed natural seeding with human serum albumin (antigen) and specific antibody and inflammatory cytokine production in vitro. Implantation of Si-scaffolds loaded with antigen-activated macrophages induced an inflammatory reaction along with antigen-specific antibody production in vivo, which could be detected even 30 days post implantation. Analysis of implant histology using scanning electron microscopy showed that Si-scaffolds could be stable for a 6-month period. Such technology leads to personalized implantable vaccines, opening novel areas of research and treatment. 相似文献
29.
Carolyn E. Schwartz Brian Stucky Carly S. Rivers Vanessa K. Noonan Joel A. Finkelstein 《Archives of physical medicine and rehabilitation》2018,99(8):1599-1608.e1
Objective
To investigate response shift effects in spinal cord injury (SCI) over 5 years postinjury.Design
Prospective cohort study observed at 1, 2, and 5 years post-SCI.Setting
Specialized SCI centers.Participants
Sample included 1125, 760, and 219 participants at 1, 2, and 5 years post-SCI (N = 2104). The study sample was 79% men; 39% were motor/sensory complete (mean age, 44.6±18.3y).Interventions
Not applicable.Main Outcome Measures
Patient-reported outcomes included the Medical Outcomes Study 36-Item Short-Form Health Survey version 2 and the Life Satisfaction-11 Questionnaire. Participant latent variable scores were adjusted for (1) potential attrition bias and (2) propensity scores reflecting risk of worse outcomes. The Oort structural equation modeling approach for detecting and accounting for response shift effects was used to test the hypothesis that people with SCI would undergo response shifts over follow-up.Results
The study data comprised the time after FIM scores, an objective measure of motor and cognitive function, had improved and stabilized. Three latent variables (Physical, Mental, and Symptoms) were modeled over time. The response shift model indicated uniform recalibration and reconceptualization response shift effects over time. When adjusted for these response shift effects, Physical showed small true change improvements at 2- and 5-year follow-up, despite FIM stability.Conclusions
We detected recalibration and reconceptualization response shift effects in 1- to 5-year follow-up of people with SCI. Despite stable motor and cognitive function, people with SCI are adapting to their condition. This adaptation reflects a progressive disconnection between symptoms and physical or mental health, and a real improvement in the Physical latent variable. 相似文献30.
目的 观察体外培养的卡氏肺孢子虫(Pc)经双氢青蒿素、青蒿琥酯作用后不同时相虫体表面结构变化。方法 将Pc接种入含HepG-2细胞的培养皿内并分别加入双氢青蒿素50μmol/L、青蒿琥酯100μmol/L、喷他脒15μmol/L、0.3%乙醇与空白对照。双氢青蒿素组于用药后1、2、4、8、12、16h作扫描电镜观察,后4组于用药后12h取样作扫描电镜观察。结果 双氢青蒿素作用2h后,Pc表面开始出现损伤,最初为表面绒毛脱落,残存绒毛肿胀呈球状,虫体体积增大。随着时间延长,虫体表面损伤明显,8h后表膜出现大小不等孔洞。青蒿琥酯组改变相同,但较轻微。结论 青蒿素衍生物可引起Pc虫体表膜损伤,通透性增加,功能障碍。 相似文献