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Graphite is one of the most chemically inert materials. Its elementary constituent, monolayer graphene, is generally expected to inherit most of the parent material's properties including chemical inertness. Here, we show that, unlike graphite, defect-free monolayer graphene exhibits a strong activity with respect to splitting molecular hydrogen, which is comparable to that of metallic and other known catalysts for this reaction. We attribute the unexpected catalytic activity to surface corrugations (nanoscale ripples), a conclusion supported by theory. Nanoripples are likely to play a role in other chemical reactions involving graphene and, because nanorippling is inherent to atomically thin crystals, can be important for two-dimensional (2D) materials in general.
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BACKGROUND: Despite the French pregnancy prevention program (PPP), a considerable number of pregnancies are potentially exposed to oral isotretinoin. New measures were taken by the French Medicines Agency, including the restriction of initial isotretinoin prescriptions to dermatology specialists in May 2015 and a new information campaign on teratogenicity in January 2019. OBJECTIVES: The aims were to: describe, between 2014 and 2021, compliance with PPP recommendations: isotretinoin use as a second-line treatment, first prescription by a dermatology specialist, monthly prescription renewal and pregnancy testing (PT); assess the effect of the 2015 and 2019 measures on PT compliance; and identify the determinants of PT noncompliance. METHODS: A retrospective cohort study was conducted among women aged 11-50 years initiating isotretinoin between 2014 and 2021 using the French Health Data System. PT compliance corresponded to pregnancy test completion and specific delays between prescription and dispensation. Time series analyses were performed to evaluate the effect of the 2015 and 2019 measures on PT compliance, and log-binomial and Poisson multivariate regression models were used to identify the determinants of PT noncompliance. RESULTS: Isotretinoin was prescribed as a second-line treatment in 64% of initiations, mainly by dermatology specialists (92%). A new monthly prescription was observed in 98% of dispensations. PT compliance reached 61%, 72% and 25% at initiation, renewals and end of treatment, respectively. The 2015 measure was associated with better PT compliance at initiation and renewals. The 2019 measure had no significant effect on PT compliance at the initiation or end of treatment but was associated with a decrease in PT compliance at renewals. Age, low socioeconomic level, initiation by a nondermatology specialist and during summer were associated with PT noncompliance. CONCLUSIONS: Understanding factors associated with PT noncompliance could help to target specific subpopulations of women treated with isotretinoin.
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Although cubic ice (ice Ic) is considered to be an important phase of water that impacts ice cloud formation in the Earth's upper atmosphere, its properties have not been studied to the same extent as those of hexagonal ice (ice Ih). This is because pristine ice Ic is not formed in simple laboratory conditions. Ice Ic formed in ambient conditions has a stacking disordered array of both hexagonal and cubic-structured hydrogen-bonded water molecules. It is therefore an active area of research to find ways of developing stacking disorder-free pure ice Ic. We demonstrate the evolution of almost pure ice Ic structure within the spherical nanopores of a hydrostable Cr-based metal-organic framework MIL-101(Cr) with an average pore size of 1 nm by low-temperature neutron diffraction study on D2O. It is observed that at temperatures below 230 K a fraction of liquid D2O transforms into ice and more than 94% of ice crystals evolved inside the pore are cubic in shape. This is a significantly high fraction of ice Ic formed under simple conditions inside the spherical pores of a Cr-based MOF. It is also observed that upon increasing the temperature, ice Ic remains stable until its melting point, without being transformed into ice Ih. This observation is in contrast to our previous observation of ice structure in the 2D cylindrical nanopores of MCM-41, where H2O ice after creeping out from the cylindrical channel was seen to be dominated by hexagonal shape. In the present study, the D2O molecules were confined into well-defined spherical nanopores, which hindered the growth of crystals above a certain size, thus minimizing the stacking disordered array. Nanoconfinement of water inside uniform spherical pores is therefore a promising method for the evolution of a significantly large fraction of cubic ice by minimizing the stacking disorder. This finding may open up the possibility of forming ice Ic with 100% cubicity under simple laboratory conditions, which will help in exploring the microphysics of ice cloud formation in the upper atmosphere.
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BACKGROUND: Oral alitretinoin is a retinoid used for severe chronic hand eczema. Although caution is recommended for patients with uncontrolled dyslipidaemia or cardiovascular risk factors, the actual atherothrombotic risk has not been investigated thus far. OBJECTIVES: To detect any excess of atherothrombotic events among patients exposed to alitretinoin, during treatment or in the 2 years following initiation. METHODS: Using the French Health Insurance database, we compared the number of patients who had an atherothrombotic event (coronary artery disease, ischaemic stroke or peripheral artery disease requiring revascularization) in the population exposed to oral alitretinoin vs. the general population of the same age, sex and baseline cardiovascular risk, using standardized morbidity ratios (SMRs). RESULTS: Between 2009 and 2017, 19 513 patients were exposed to oral alitretinoin in France. Sixty-four (0·3%) patients had an atherothrombotic event while on alitretinoin. Patients receiving alitretinoin experienced no more atherothrombotic events than the general population: patients without cardiovascular risk factors or previous atherothrombotic events had a SMR of 0·65 [95% confidence interval (CI) 0·26-1·34] during alitretinoin treatment, and 1·21 (95% CI 0·90-1·59) in the 2 years following initiation; patients with cardiovascular risk factors or previous atherothrombotic events had a SMR of 0·82 (95% CI 0·60-1·08) during alitretinoin treatment and 0·95 (95% CI 0·82-1·09) in the 2 years following initiation. Taken separately, SMRs for each outcome did not increase either. CONCLUSIONS: These data from an exhaustive nationwide population-based study do not support an increase in the incidence of atherothrombotic events with alitretinoin use, regardless of the baseline cardiovascular risk of the patient.
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Isquemia Encefálica , Fármacos Dermatológicos , Acidente Vascular Cerebral , Alitretinoína , Estudos de Coortes , Humanos , Tretinoína/efeitos adversosRESUMO
BACKGROUND: Growing evidence indicates that amoxicillin induces herpesvirus replication in vitro. As these play a central pathophysiological role in Drug Reaction with Eosinophilia and Systemic Symptoms syndrome (DRESS), amoxicillin could present with specific DRESS features. OBJECTIVE: To characterize the onset patterns of amoxicillin-associated DRESS. METHODS: All cases of DRESS (Kardaun score ≥4) involving amoxicillin and reported in the French Pharmacovigilance Database between January 1, 2004 and November 30, 2019 were included. Onset circumstances for these cases were categorized considering the onset delay from amoxicillin initiation, and the presence of concomitant medications with a compatible time to onset. RESULTS: A total of 146 probable cases or definite cases of DRESS were included. Three onset circumstances were identified: (i) 'amoxicillin clear culprit' where amoxicillin was the sole suspect drug or when concomitant drugs of compatible time to onset were not reported to cause DRESS (n = 62); (ii) 'amoxicillin possible culprit' in the presence of other potentially culprit drugs in addition to amoxicillin (n = 44) and (iii) 'flare' where amoxicillin, used after DRESS onset, induced flare-up reactions (n = 40). The median time to onset was 5 days (IQR 2-11) in 'clear culprit', and 18 days (IQR 7-26) in 'possible culprit' cases. In 'flare' cases, the median latency between amoxicillin initiation and flare-up reactions was 3 days (IQR 2-5). CONCLUSIONS: Amoxicillin can induce DRESS with a specific early onset and exacerbate DRESS from another drug.
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Síndrome de Hipersensibilidade a Medicamentos , Eosinofilia , Amoxicilina/efeitos adversos , Bases de Dados Factuais , Síndrome de Hipersensibilidade a Medicamentos/epidemiologia , Síndrome de Hipersensibilidade a Medicamentos/etiologia , Eosinofilia/induzido quimicamente , Humanos , FarmacovigilânciaRESUMO
We have thoroughly investigated the crystal structure of ice evolved from super cooled water confined in MCM-41 cylindrical nano pores through a synchrotron-based X-ray diffraction (XRD) technique for two different levels of pore filling. A rigorous analysis of XRD data shows that the nucleation dynamics and the structure of nucleated ice highly depend on the level of pore filling. In the nearly fully hydrated pores, ice crystallites start nucleating inside the pores below 240 K and creep out of the pores to form bulk crystals having crystalline structure of a mixed phase of hexagonal and cubic forms. In the partially hydrated pores, on the other hand, ice crystals cannot creep out of the pore crossing the energy barrier. The crystalline ice particles remaining inside the cylindrical pore show a short range "cubic rich" structure. The "pure cubic" phase has not been identified at either of the pore fillings in these 2.5 nm average size pores. A large fraction of water inside the pores remains in the super cooled liquid phase even at 180 K. This observation is relevant for understanding the ice nucleation through the pore condensation and freezing mechanism, which is a major pathway for the formation of cirrus clouds in the upper atmosphere.
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BACKGROUND AND AIMS: Studies suggest that Gentiana lutea (GL), and its component isovitexin, may exhibit anti-atherosclerotic properties. In this study we sought to investigate the protective mechanism of GL aqueous root extract and isovitexin on endothelial inflammation, smooth muscle cell migation, and on the onset and progression of atherosclerosis in streptozotocin (STZ)-induced diabetic rats. METHODS AND RESULTS: Our results show that both GL extract and isovitexin, block leukocyte adhesion and generation of reactive oxygen species in human umbilical vein endothelial cells (HUVECs) and rat aortic smooth muscle cells (RASMCs), following TNF-alpha and platelet derived growth factor-BB (PDGF-BB) challenges respectively. Both the extract and isovitexin blocked TNF-α induced expression of ICAM-1 and VCAM-1 in HUVECs. PDGF-BB induced migration of RASMCs and phospholipase C-γ activation, were also abrogated by GL extract and isovitexin. Fura-2 based ratiometric measurements demonstrated that, both the extact, and isovitexin, inhibit PDGF-BB mediated intracellular calcium rise in RASMCs. Supplementation of regular diet with 2% GL root powder for STZ rats, reduced total cholesterol in blood. Oil Red O staining demonstrated decreased lipid accumulation in aortic wall of diabetic animals upon treatment with GL. Medial thickness and deposition of collagen in the aortic segment of diabetic rats were also reduced upon supplementation. Immunohistochemistry demonstrated reduced expression of vascular cell adhesion molecule-1 (VCAM-1), inducible nitric oxide synthase (iNOS), and vascular endothelial cadherin (VE-cadherin) in aortic segments of diabetic rats following GL treatment. CONCLUSIONS: Thus, our results support that GL root extract/powder and isovitexin exhibit anti-atherosclerotic activities.
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Apigenina/farmacologia , Movimento Celular/efeitos dos fármacos , Gentiana/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Inflamação/tratamento farmacológico , Miócitos de Músculo Liso/efeitos dos fármacos , Animais , Aorta/citologia , Aorta/efeitos dos fármacos , Aorta/metabolismo , Arteriosclerose/tratamento farmacológico , Becaplermina , Colesterol/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Miócitos de Músculo Liso/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fosfolipase C gama/metabolismo , Raízes de Plantas/química , Proteínas Proto-Oncogênicas c-sis/farmacologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismoRESUMO
Jute is the most important phloem fiber crop of the world, and is mainly grown in the South East Asian countries of India, Bangladesh, Nepal, China, Indonesia, Thailand, and Myanmar, and few South American countries. The fiber is used in making sacks, ropes, bags, carpets, shoes, geo-textiles, and home decorations. There are two kinds of jute: tossa jute (Corchorus olitorius L.) and white jute (C. capsularis). In June 2012, symptoms suggestive of phytoplasma infection (little leaf and bunchy top) were noticed on tossa jute in different experimental fields of the CRIJAF research farm, Barrackpore, India, and the incidence of the disease varied from 5 to 20%. The infected plants showed profuse lateral branching with a bushy appearance. In many plants, branching at the apical portion developed a bunchy top symptom with tufts of smaller leaves. Leafy stem was also common in many plants with main stems covered with numerous little leaves. Total DNA was extracted from leaf midveins of 15 symptomatic and 5 asymptomatic plants by using an improved salt concentration and simple sodium acetate CTAB method (1). PCR was carried out with universal P1/P7 primer set followed by nested primer pair R16F2n/R16R2 (3), resulting in DNA amplicons that were 1.8 kb and 1.2 kb, respectively, in all symptomatic samples tested. Phytoplasma was not detected in symptomless samples. The five purified nested products were cloned in a pGEM-T Easy vector (Promega) and sequenced. One of the sequences that proved to be identical was deposited in GenBank (Accession No. KF501045). The consensus sequence was analyzed by NCBI BLAST and found to share 99% similarity with the 16Sr DNA sequence of the alder yellows phytoplasma reference strain (GenBank Accession No. AY028789), which belongs to the 16SrV group. The phylogenetic tree based on the 16SrDNA sequence of phytoplasmas belonging to group 16SrV and other distinct phytoplasma groups also showed that the phytoplasma clustered with members of subgroup 16SrV (4). Subsequently, in silico RFLP analysis of the nested PCR product with the pDRAW32 program using AluI and TruI restriction site used for 16SrV subgroups A, B, C, D, and E indicated that the 16SrV Corchorus strain belonged to subgroup C. RFLP patterns from all symptomatic C. olitorius samples were identical to the 16SrV-C pattern (2). The vector species transmitting the concerned phytoplasma in C. olitorius still needs to be identified. The leaf hopper, Amrasca biguttula biguttula, may be a potential vector as it is often noticed in jute fields. To the best of our knowledge, this is the first report of 16SrV-C phytoplasma associated with tossa jute (C. olitorius) in India. Initiative has to be taken to manage this disease; otherwise, branching of the main stems would badly affect the fiber quality as well as yield. References: (1) C. Biswas et al. Lett. Appl. Microbiol. 56:105, 2012. (2) B. Duduk et al. J. Phytopathology 152:575, 2004. (3) I. M. Lee et al. Int. J. Syst. Evol. Microbiol. 54:337, 2004. (4) N. Saitou and M. Nei. Mol. Biol. Evol. 4:406, 1987.
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Jute (Corchorus olitorius L.) is an important bast fiber crop that is mainly grown in the Southeast Asian countries like India, Bangladesh, Nepal, China, Indonesia, Thailand, Myanmar, and a few South American countries. In June 2013, symptoms suggestive of a viral disease were noticed on jute (cv. JRO524) in an experimental field of the CRIJAF research farm, Barrackpore, India, and the incidence of the disease was less than 2%. The infected plants showed stunted growth and short height. Mostly the upper leaves elongated with curling and coiling of lamina. Puckering and shoe string effect were also noticed. Petioles and stipules of the affected leaves were exceptionally longer. Although initially the incidence was low, it may spread to larger areas in subsequent years. Because the jute fiber is extracted from the stem, stunted growth and short height would badly affect the fiber yield and quality. Ten symptomatic and ten asymptomatic healthy looking samples were collected from the field. Corchorus golden mosaic begomovirus is common in jute; therefore, all the samples were tested by PCR using JMFL-AF/JMFL-AR, DNA-A component specific primer pair and JMFL-BF/JMFL-BR, DNA-B component specific primer pairs (1). However, there was no amplification. Because the aphid Aphis gossypii was often noticed in the jute field, all the samples were tested by double-antibody sandwich (DAS)-ELISA for common aphid transmitted viruses, e.g., Cucumber mosaic virus, Bean common mosaic virus, Cowpea mosaic virus, Papaya ring spot virus, Potato leaf roll virus (PLRV), Potato virus Y, and Watermelon mosaic virus using commercial diagnostic kits (Agdia). The symptomatic samples showed positive reaction only for PLRV. Five ELISA-positive samples and five asymptomatic healthy samples were used for RNA extraction. Total RNA was extracted by using QIAGEN RNeasy mini kit. RT-PCR was carried out with PLRV CP gene specific primer pair (3) which generated a cDNA amplicon of 627 bp in all ELISA-positive symptomatic samples. PLRV was not detected in symptomless samples. The five purified cDNA products were cloned in a pGEM-T Easy vector (Promega) and were sequenced. One of the five identical sequences was deposited in GenBank (Accession No. KF233880). The consensus sequence was analyzed by NCBI BLAST and found to share 99% similarity with the coat protein sequence of PLRV reference strain (S77421). Nucleotide span and ORF finder (NCBI) analysis indicated the 627-bp PCR amplicon coded part of a coat protein gene that had 100% identity with translated gene product (Protein ID AAB33483). PLRV is a small isometric RNA virus with worldwide distribution belonging to the family Luteoviridae whose natural host range is mainly restricted to solanaceous plants and few plants of other families (2,4). To the best of our knowledge, this is the first report of PLRV naturally occurring on jute (C. olitorius). References: (1) R. Ghosh et al. J. Virol. Methods 159:34, 2009. (2) S. Guyader and D. G. Ducray. J. Gen. Virol. 83:1799, 2002. (3) M. A. Mayo et al. J. Gen. Virol. 70:1037, 1989. (4) K. Mukherjee et al. Virus Genes 26:247, 2003.
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A simple method was developed for isolating DNA from jute seed, which contains high amounts of mucilage and secondary metabolites, and a PCR protocol was standardized for detecting the seedborne pathogen Macrophomina phaseolina. The cetyl trimethyl ammonium bromide method was modified with increased salt concentration and a simple sodium acetate treatment to extract genomic as well as fungal DNA directly from infected jute seed. The Miniprep was evaluated along with five other methods of DNA isolation in terms of yield and quality of DNA and number of PCR positive samples. The Miniprep consistently recovered high amounts of DNA with good spectral qualities at A260/A280. The DNA isolated from jute seed was found suitable for PCR amplification. Macrophomina phaseolina could be detected by PCR from artificially inoculated as well as naturally infected jute seeds. The limit of PCR-based detection of M. phaseolina in jute seed was determined to be 0·62 × 10(-7) CFU g(-1) seed.
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Ascomicetos/isolamento & purificação , Corchorus/microbiologia , DNA Fúngico/isolamento & purificação , Sementes/microbiologia , Ascomicetos/genética , Corchorus/genética , Limite de Detecção , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase/métodosRESUMO
Jute (Corchorus olitorius L.) is the second most important fiber crop after cotton in terms of global production (3). In November 2011, symptoms suggestive of bacterial infection were observed on a seed crop of jute at the CRIJAF research farm, Barrackpore, West Bengal, India. The disease appeared as small, brown, circular spots, usually less than 5 mm in diameter on the leaves and some of the spots were surrounded by a yellow halo. The lesions on the stems were elongated and in some cases were found to girdle the stem. In the later stages of disease, brown sunken spots were found on the green capsules. Disease incidence varied from about 20% to 90% of the total plants in different affected fields at the CRIJAF research farm. Bacterial leaf spot of jute with similar symptoms was reported in 1957 from Sudan (4). Five symptomatic and three asymptomatic leaf samples were collected from different jute fields. Bacterial colonies isolated on nutrient agar medium from infected young leaves were Xanthomonas-like and pale yellow cream in color. Total DNA was extracted from symptomatic as well as asymptomatic leaf samples by using an improved salt concentration and simple sodium acetate CTAB method (2). Single bacterial colonies were transferred to nutrient agar (NA) medium plates and incubated at 28°C for 48 h. Pure colonies from plates were used directly for DNA extraction using the QIAGEN DNeasy Blood and Tissue kit. PCR was carried out with Xanthomonas campestris specific primers NZ8F3/NZ85R3 (1), which generated an amplicon of 530 bp from all the symptomatic leaf samples as well as pure cultures of the isolated bacteria. No amplification was obtained from asymptomatic leaves. The amplicons from the five symptomatic samples collected from the field were sequenced and showed 100% identity with one another, and one sequence (strain JB-CO-13) was deposited in GenBank (Accession No. KC342185). The BLASTn analysis revealed that bacterial strain JB-CO-13 had 100% identity with X. campestris pv. olitorii (EU285213). Nucleotide span and ORF finder (NCBI) analysis indicated the 530-bp PCR amplicon coded part of a gyrase B gene that had 100% identity with a translated gene product (Protein ID: ABX84334). Three leaves of five 1-month-old jute plants (cv. JRO 204) in pot culture were infiltrated each with a separate bacterial strain using suspensions (1 × 105 CFU/ml) in distilled water. The negative control consisted of leaves infiltrated with sterile distilled water. The plants were kept in a greenhouse with mean maximum and minimum temperatures of 28.96 and 21.8°C, respectively. The plants were covered with plastic bags to maintain high relative humidity (>80%). Typical bacterial lesions were recorded on all the inoculated plants after 1 week. No lesions were seen on the negative control. To the best of our knowledge, this is the first report of bacterial leaf spot on C. olitorius caused by X. campestris pv. olitorii from India. References: (1) J. Adriko et al. Plant Pathol. 61:489, 2012. (2) C. Biswas, et al. Lett. Appl. Microbiol. 56:105, 2013. (3) Food and Agriculture Organization of the United Nations. Agricultural Commodities: Profiles and Relevant WTO Negotiating Issues. Online: http://www.fao.org/docrep/006/Y4343E/y4343e03.htm , 2003. (4) K. A. Sabet. Ann. Appl. Biol. 45:516, 1957.
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Space resource utilisation is opening a new space era. The scientific proof of the presence of water ice on the south pole of the Moon, the recent advances in oxygen extraction from lunar regolith, and its use as a material to build shelters are positioning the Moon, again, at the centre of important space programs. These worldwide programs, led by ARTEMIS, expect robotics to be the disrupting technology enabling humankind's next giant leap. However, Moon robots require a high level of autonomy to perform lunar exploration tasks more efficiently without being constantly controlled from Earth. Furthermore, having more than one robotic system will increase the resilience and robustness of the global system, improving its success rate, as well as providing additional redundancy. This paper introduces the Resilient Exploration and Lunar Mapping System, developed with a scalable architecture for semi-autonomous lunar mapping. It leverages Visual Simultaneous Localization and Mapping techniques on multiple rovers to map large lunar environments. Several resilience mechanisms are implemented, such as two-agent redundancy, delay invariant communications, a multi-master architecture different control modes. This study presents the experimental results of REALMS with two robots and its potential to be scaled to a larger number of robots, increasing the map coverage and system redundancy. The system's performance is verified and validated in a lunar analogue facility, and a larger lunar environment during the European Space Agency (ESA)-European Space Resources Innovation Centre Space Resources Challenge. The results of the different experiments show the efficiency of REALMS and the benefits of using semi-autonomous systems.
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The present study describes the activity of a nanomaterial on protoscoleces of Echinococcus granulosus, which exhibited morphological changes and apoptosis. Apoptotic changes were deduced on the basis of effector caspase activation and nucleosomal laddering. Invaginated protoscoleces maintained in vitro became evaginated and had hooks, presumptive suckers and stalks. Degenerative changes of protoscoleces were evidenced after treatment with praziquantel and nano-combination. Protoscoleces treated with praziquantel had distinct attestation of necrosis and nano-combination-treated protoscoleces had signatures of apoptosis.
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Anti-Helmínticos/farmacologia , Echinococcus granulosus/efeitos dos fármacos , Nanoestruturas/química , Praziquantel/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Echinococcus granulosus/citologia , Echinococcus granulosus/enzimologia , Proteínas de Helminto/metabolismoRESUMO
Ichthyophthirius multifiliis, a ciliated parasite causing ichthyophthiriasis (white spot disease) in freshwater fishes, results in significant economic loss to the aquaculture sector. One of the important predisposing factors for ichthyophthiriasis is low water temperature (i.e., below 20°C), which affects the health and makes freshwater fishes more susceptible to parasitic infections. During ichthyophthiriasis, fishes are stressed and acute immune reactions are compromised, which enables the aquatic bacterial pathogens to simultaneously infect the host and increase the severity of disease. In the present work, we aimed to understand the parasite-bacteria co-infection mechanism in fish. Later, Curcuma longa (turmeric) essential oil was used as a promising management strategy to improve immunity and control co-infections in fish. A natural outbreak of I. multifiliis was reported (validated by 16S rRNA PCR and sequencing method) in Pangasianodon hypophthalmus from a culture facility of ICAR-CIFRI, India. The fish showed clinical signs including hemorrhage, ulcer, discoloration, and redness in the body surface. Further microbiological analysis revealed that Aeromonas hydrophila was associated (validated by 16S rRNA PCR and sequencing method) with the infection and mortality of P. hypophthalmus, confirmed by hemolysin and survival assay. This created a scenario of co-infections, where both infectious agents are active together, causing ichthyophthiriasis and motile Aeromonas septicemia (MAS) in P. hypophthalmus. Interestingly, turmeric oil supplementation induced protective immunity in P. hypophthalmus against the co-infection condition. The study showed that P. hypophthalmus fingerlings supplemented with turmeric oil, at an optimum concentration (10 ppm), exhibited significantly increased survival against co-infection. The optimum concentration induced anti-stress and antioxidative response in fingerlings, marked by a significant decrease in cortisol and elevated levels of superoxide dismutase (SOD) and catalase (CAT) in treated animals as compared with the controls. Furthermore, the study indicated that supplementation of turmeric oil increases both non-specific and specific immune response, and significantly higher values of immune genes (interleukin-1ß, transferrin, and C3), HSP70, HSP90, and IgM were observed in P. hypophthalmus treatment groups. Our findings suggest that C. longa (turmeric) oil modulates stress, antioxidant, and immunological responses, probably contributing to enhanced protection in P. hypophthalmus. Hence, the application of turmeric oil treatment in aquaculture might become a management strategy to control co-infections in fishes. However, this hypothesis needs further validation.
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Peixes-Gato , Infecções por Cilióforos , Coinfecção , Doenças dos Peixes , Hymenostomatida , Óleos Voláteis , Aeromonas hydrophila , Animais , Antioxidantes/uso terapêutico , Catalase , Infecções por Cilióforos/parasitologia , Infecções por Cilióforos/veterinária , Curcuma , Surtos de Doenças , Proteínas Hemolisinas , Hidrocortisona/uso terapêutico , Imunoglobulina M/uso terapêutico , Interleucina-1beta , Complexo Ferro-Dextran/uso terapêutico , Óleos Voláteis/farmacologia , RNA Ribossômico 16S , Superóxido Dismutase , Transferrinas/uso terapêutico , ÁguaRESUMO
Deep learning generative approaches provide an opportunity to broadly explore protein structure space beyond the sequences and structures of natural proteins. Here, we use deep network hallucination to generate a wide range of symmetric protein homo-oligomers given only a specification of the number of protomers and the protomer length. Crystal structures of seven designs are very similar to the computational models (median root mean square deviation: 0.6 angstroms), as are three cryo-electron microscopy structures of giant 10-nanometer rings with up to 1550 residues and C33 symmetry; all differ considerably from previously solved structures. Our results highlight the rich diversity of new protein structures that can be generated using deep learning and pave the way for the design of increasingly complex components for nanomachines and biomaterials.
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Aprendizado Profundo , Engenharia de Proteínas , Materiais Biocompatíveis/química , Microscopia Crioeletrônica , Modelos Moleculares , Conformação Proteica , Engenharia de Proteínas/métodos , Subunidades Proteicas/químicaRESUMO
Although deep learning has revolutionized protein structure prediction, almost all experimentally characterized de novo protein designs have been generated using physically based approaches such as Rosetta. Here, we describe a deep learning-based protein sequence design method, ProteinMPNN, that has outstanding performance in both in silico and experimental tests. On native protein backbones, ProteinMPNN has a sequence recovery of 52.4% compared with 32.9% for Rosetta. The amino acid sequence at different positions can be coupled between single or multiple chains, enabling application to a wide range of current protein design challenges. We demonstrate the broad utility and high accuracy of ProteinMPNN using x-ray crystallography, cryo-electron microscopy, and functional studies by rescuing previously failed designs, which were made using Rosetta or AlphaFold, of protein monomers, cyclic homo-oligomers, tetrahedral nanoparticles, and target-binding proteins.
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Aprendizado Profundo , Engenharia de Proteínas , Proteínas , Sequência de Aminoácidos , Microscopia Crioeletrônica , Cristalografia por Raios X , Conformação Proteica , Engenharia de Proteínas/métodos , Proteínas/químicaAssuntos
Síndrome de Hipersensibilidade a Medicamentos/epidemiologia , Farmacovigilância , Adulto , Idoso , Alopurinol/efeitos adversos , Anti-Infecciosos/efeitos adversos , Anticoagulantes/efeitos adversos , Anticonvulsivantes/efeitos adversos , Feminino , França/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fenindiona/efeitos adversos , Fenindiona/análogos & derivados , Medição de Risco/métodosRESUMO
Echinococcus granulosus is a parasitic helminth which affects both man and animals. During infection with larval stage of the organism secretory and membrane-bound (S/M) proteins play a meaningful role for evasion of immune system. Antigen B (AgB) is one of them. Present investigation has defined sequence diversity of AgB2 subunit of cattle and buffalo isolates of the organism. A total of 55 isolates were screened by polymerase chain reaction based single stranded conformation polymorphism (PCR-SSCP). Subsequently, six conformers could be detected. Based on predicted amino acid sequences of 90 amino acid residues, three clusters could be deduced. Sequence information of two buffalo isolates was homologous to AgB4 indicating gene switching phenomenon in between closely related isoforms. Numerical value of Tajima's D test proved negative selection pressure. Using artificial neural network (ANN), B cell linear epitope and stretches of agretope were predicted. Three clusters could be defined on the basis of B cell linear epitope. Out of three clusters, two showed more than 50% binding propensity with same MHCII alleles whereas, cluster 3 exhibited binding propensity with other MHCII alleles (DRB1_1501, DRB1_1502). Relative expression of AgB2 was more in active cysts (1.636 ± 0.092) followed by degenerating (0.449 ± 0.037) and calcified (0.255 ± 0.008). This result suggested that relative expression of AgB2 declines with progression of the disease. Using recombinant AgB2 sensitivity, specificity and accuracy of the ELISA test was 96.7, 94.7 and 95.9%, respectively. No cross reactivity was found with common cestode and trematode infected cattle and buffalo because cross reactive antigen was expressed intracellularly. Finally, this was concluded that AgB2 is the suitable immunological marker for detection, diagnosis and progression of the disease.