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1.
Plant Cell Rep ; 43(1): 27, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38163826

RESUMO

KEY MESSAGE: In this review, we made an attempt to create a holistic picture of plant response to a rising temperature environment and its impact by covering all aspects from temperature perception to thermotolerance. This comprehensive account describing the molecular mechanisms orchestrating these responses and potential mitigation strategies will be helpful for understanding the impact of global warming on plant life. Organisms need to constantly recalibrate development and physiology in response to changes in their environment. Climate change-associated global warming is amplifying the intensity and periodicity of these changes. Being sessile, plants are particularly vulnerable to variations happening around them. These changes can cause structural, metabolomic, and physiological perturbations, leading to alterations in the growth program and in extreme cases, plant death. In general, plants have a remarkable ability to respond to these challenges, supported by an elaborate mechanism to sense and respond to external changes. Once perceived, plants integrate these signals into the growth program so that their development and physiology can be modulated befittingly. This multifaceted signaling network, which helps plants to establish acclimation and survival responses enabled their extensive geographical distribution. Temperature is one of the key environmental variables that affect all aspects of plant life. Over the years, our knowledge of how plants perceive temperature and how they respond to heat stress has improved significantly. However, a comprehensive mechanistic understanding of the process still largely elusive. This review explores how an increase in the global surface temperature detrimentally affects plant survival and productivity and discusses current understanding of plant responses to high temperature (HT) and underlying mechanisms. We also highlighted potential resilience attributes that can be utilized to mitigate the impact of global warming.


Assuntos
Aquecimento Global , Plantas , Mudança Climática , Aclimatação , Temperatura
2.
Nucleic Acids Res ; 51(16): 8383-8401, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37526283

RESUMO

Gene functional descriptions offer a crucial line of evidence for candidate genes underlying trait variation. Conversely, plant responses to environmental cues represent important resources to decipher gene function and subsequently provide molecular targets for plant improvement through gene editing. However, biological roles of large proportions of genes across the plant phylogeny are poorly annotated. Here we describe the Joint Genome Institute (JGI) Plant Gene Atlas, an updateable data resource consisting of transcript abundance assays spanning 18 diverse species. To integrate across these diverse genotypes, we analyzed expression profiles, built gene clusters that exhibited tissue/condition specific expression, and tested for transcriptional response to environmental queues. We discovered extensive phylogenetically constrained and condition-specific expression profiles for genes without any previously documented functional annotation. Such conserved expression patterns and tightly co-expressed gene clusters let us assign expression derived additional biological information to 64 495 genes with otherwise unknown functions. The ever-expanding Gene Atlas resource is available at JGI Plant Gene Atlas (https://plantgeneatlas.jgi.doe.gov) and Phytozome (https://phytozome.jgi.doe.gov/), providing bulk access to data and user-specified queries of gene sets. Combined, these web interfaces let users access differentially expressed genes, track orthologs across the Gene Atlas plants, graphically represent co-expressed genes, and visualize gene ontology and pathway enrichments.


Assuntos
Genes de Plantas , Transcriptoma , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Filogenia , Software , Transcriptoma/genética , Atlas como Assunto
3.
Rev Esp Patol ; 55(3): 197-202, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-35779887

RESUMO

The lipomatous variety solitary fibrous tumor is a soft tissue neoplasm composed of mature adipose tissue and hemangiopericytoma areas. A 53-year-old man consulted for facial asymmetry and maxillofacial magnetic resonance imaging showed a cystic lesion, 3 x 2 cm in size, in front of the anterior wall of the maxillary sinus. Histologically, there were dense spindle cells expressing CD34, CD99, Bcl-2, and STAT6, myxoid zones, hemangiopericytomatous blood vessels, and S100 positive adipocytes. NAB2/STAT6 gene fusion was revealed by RT-PCR. The main differential diagnosis was raised with the spindle cell lipoma and malignant variant of the lipomatous solitary fibrous tumor. STAT6 overexpression and NAB2/STAT6 gene fusion are specific for lipomatous solitary fibrous tumor and the presence of lipoblasts and atypical lipomatous tumor areas suggests malignancy. These tumors located in the head and neck region have a benign biological behavior.


Assuntos
Hemangiopericitoma , Lipoma , Tumores Fibrosos Solitários , Tecido Adiposo/patologia , Fusão Gênica , Hemangiopericitoma/genética , Hemangiopericitoma/patologia , Humanos , Lipoma/genética , Masculino , Pessoa de Meia-Idade , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fator de Transcrição STAT6/genética , Tumores Fibrosos Solitários/genética , Tumores Fibrosos Solitários/patologia
4.
Arch Physiol Biochem ; 128(1): 92-100, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31560224

RESUMO

The current study evaluates the efficacy of methanolic extract of Rotula aquatica Lour. (MERA) against inflammatory changes associated with acute pyelonephritis. The antioxidant enzymes such as SOD, CAT, GPx, GR and oxidative stress markers like GSH content, malondialdehyde (MDA) level, nitrate level, reactive oxygen species (ROS) level and renal toxicity markers were evaluated in this study. The mRNA level expression of Toll-like receptor 4 (TLR-4), nuclear transcription factor kappa B (NF-κB), tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and Tamm Horsfall protein (THP) were studied by RT-PCR analysis. The oral administration of MERA increases the antioxidant enzyme status in pyelonephritis rat. The elevated levels of oxidative stress markers in pyelonephritic rats were ameliorated by the administration of MERA at 100 mg/kg and 200 mg/kg bwt of the rat. The mRNA level expression of major genes were restored to normal level by MERA.


Assuntos
Boraginaceae/química , Estresse Oxidativo , Extratos Vegetais/farmacologia , Pielonefrite , Animais , Antioxidantes , Inflamação , NF-kappa B/metabolismo , Pielonefrite/tratamento farmacológico , Ratos , Espécies Reativas de Oxigênio
6.
Vet Anim Sci ; 11: 100160, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33532660

RESUMO

Porcine Stress Syndrome (PSS) is a disorder codified by the ryanodine receptor 1 gene (RYR1) and affects both animal welfare and the quality of the meat product. As a consequence, individuals with this syndrome generate great worldwide economic losses in the porcine industry. In Argentina, the Buenos Aires Province is the most involved on this activity, and productions are to be in open field with a higher frequency of pigs with diverse pathologies. On the other hand, the biggest and oldest wild pigs population is located on the Atlantic coast of Buenos Aires Province, which presents a continuous bidirectional flow of individuals with the productive areas nearby. The aim of this study is to detect the presence of the RYR1 deleterious allele in the wild population from the Atlantic coast of Buenos Aires, in order to evaluate its possible role as a genetic reservoir for said allele. For this purpose, 106 wild pigs from 28 sites were studied, finding a 6.6% of carrier individuals, indicating that the wild population is not free of this allele. This constitutes the first analysis to detect the presence of the RYR1 deleterious allele, associated to the PSS in wild pigs from Argentina, being one of the few studies to report it worldwide and suggesting wild pigs populations to be a possible genetic reservoir for this disease.

7.
Microb Pathog ; 147: 104348, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32561418

RESUMO

Bacterial pathogens cause significant challenge to the ornamental fish industry. Eventhough antibiotic administration has been recommended to manage fish diseases, there is alarming concern with emergence of antibiotic resistance. This indicates the need for the development of alternative methods with multi-targeted action to manage fish diseases. In the study, silver (AgNPs) and zinc oxide (ZnONPs) nanoparticles have been evaluated for its activity against Aeromonas veronii. Both the AgNPs and ZnONPs were found to have bactericidal activity against A. veronii. In vivo experiments with A. veronii was found to cause severe mortality in Xiphophorus hellerii with a LD50 of 1.4 × 108 CFU/mL. However, treatment with AgNPs and ZnONPs each at a concentration of 1 mg/L was found to enhance the survival rate of X. hellerii to 83.3% and 100% respectively. Further histopathological analysis showed alterations in gill, intestine and liver of X. hellerii due to A. veronii in the infection control. In the case of AgNPs treated group, symptoms of moderate tissue damage could be observed. However, the ZnONPs treated X. hellerii showed normal histological features with minimum tissue damage. The bath dip method further confirmed the protective ability of the zinc oxide nanoparticles (1 mg/L) on X. hellerii.


Assuntos
Ciprinodontiformes , Infecções por Bactérias Gram-Negativas , Nanopartículas Metálicas , Óxido de Zinco , Aeromonas veronii , Animais , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Prata
8.
Plant Cell ; 32(5): 1519-1535, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32111671

RESUMO

Asymmetric cell division (ACD) and positional signals play critical roles in the tissue patterning process. In the Arabidopsis (Arabidopsis thaliana) root meristem, two major phloem cell types arise via ACDs of distinct origins: one for companion cells (CCs) and the other for proto- and metaphloem sieve elements (SEs). The molecular mechanisms underlying each of these processes have been reported; however, how these are coordinated has remained elusive. Here, we report a new phloem development process coordinated via the SHORTROOT (SHR) transcription factor in Arabidopsis. The movement of SHR into the endodermis regulates the ACD for CC formation by activating microRNA165/6, while SHR moving into the phloem regulates the ACD generating the two phloem SEs. In the phloem, SHR sequentially activates NAC-REGULATED SEED MORPHOLOGY 1 (NARS1) and SECONDARY WALL-ASSOCIATED NAC DOMAIN PROTEIN 2 (SND2), and these three together form a positive feedforward loop. Under this regulatory scheme, NARS1, generated in the CCs of the root differentiation zone, establishes a top-down signal that drives the ACD for phloem SEs in the meristem. SND2 appears to function downstream to amplify NARS1 via positive feedback. This new regulatory mechanism expands our understanding of the sophisticated vascular tissue patterning processes occurring during postembryonic root development.plantcell;32/5/1519/FX1F1fx1.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Floema/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Transdução de Sinais , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Divisão Celular Assimétrica , Diferenciação Celular , Regulação da Expressão Gênica de Plantas , Genoma de Planta , MicroRNAs/genética , MicroRNAs/metabolismo , Floema/citologia , Floema/genética , Raízes de Plantas/citologia , Raízes de Plantas/genética , Fatores de Transcrição/genética
9.
Microb Pathog ; 142: 104049, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-32045643

RESUMO

Plant growth-promoting rhizobacteria are indigenous beneficial bacteria that will enhance plant growth as well as suppress phytopathogens. In the present study, the isolate KTMA4 showed the highest inhibition against major phytopathogens of tomato; Fusarium oxysporum (66%) and Alternaria solani (54%) after seven days of incubation. Analysis of the 16S rRNA gene sequence revealed that the isolate KTMA4 is Bacillus cereus (MG547975). The isolate produced in vitro plants growth-promoting factors such as Indole-3-acetic acid, ammonia, catalase, siderophore and 1-aminocyclopropane-1-carboxylate deaminase and it has nitrogen fixation ability. The bacterial strain has also produced lytic enzymes such as amylase, cellulase, xylanase, lipase, and protease. Moreover, the bacterium Bacillus cereus KTMA4 effectively produced biofilm, biosurfactants and salt-tolerant (5% NaCl). The bacterium exhibited intrinsic antibiotic resistance. The in vivo studies using tomato plants grown from seeds treated with the bacterial strain KTMA4 demonstrated an enhancement in seed germination percentage (86.66 ± 2.88) and vigour index (637.5 ± 21.65) over the uninoculated control (germination percentage- 28.33 ± 2.88 and vigour index- 42.5 ± 4.33). 60 days of greenhouse study revealed that the bacterial isolate enhanced the plant growth significantly (P ≤ 0.05) compared to the uninoculated control and the treated plants. Therefore the study suggests that the newly isolated rhizosphere bacterial strain can be used as a potential biocontrol agent against a multitude of fungal pathogens as well as a biofertilizer inoculant for tomato cultivation.

10.
Microb Pathog ; 138: 103832, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31689474

RESUMO

The mycofabrication of silver nanoparticles (AgNPs) through green chemistry protocol is an advanced methodological progress in medical nanotechnology. Mycofabricated AgNPs are less toxic due to an aura of biomolecules around the nanoparticles. Hence the mycofabricated AgNPs can be used for clinical applications. The present study explores the antibiofilm activity of mycogenerated AgNPs, which were synthesized by the enzymatic reduction of silver nitrate using the marine algicolous endophytic fungus Penicillium polonicum ARA10. The mycogenerated AgNPs showed very specific and potent bactericidal activity against Acinetobacter baumannii. Anti-A.baumannii activities of mycogenerated AgNPs on planktonic as well as biofilm embedded cells were explored. The physical impact of synthesized AgNPs on A.baumannii was investigated by scanning electron microscopy and fluorescence microscopy. A bionanocomposite coating for the central venous catheter (CVC) was formulated using the mycogenerated AgNPs and polydopamine. The bionanocomposite surface was characterized by field emission scanning electron microscopy, water contact angle measurement, and Raman spectroscopy. The results showed that the mycogenerated AgNPs have potent antibiofilm activity on biofilms of A.baumannii. The scanning electron microscopy (SEM) and fluorescence microscopy images showed noticeable aberrations on the ultrastructure of A.baumannii. The SEM and FE-SEM images of biofilms on the surface of CVC samples proved that the AgNPs at minimum bactericidal concentration could destroy the structure of biofilms and lyses the bacterial cell. Thus, the present study establishes a new way to the development of 'antibacterial surfaces' based on mycogenerated AgNPs.


Assuntos
Acinetobacter baumannii , Biofilmes/efeitos dos fármacos , Cateteres Venosos Centrais/microbiologia , Nanopartículas Metálicas , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/crescimento & desenvolvimento , Antibacterianos/química , Biofilmes/crescimento & desenvolvimento , Biotecnologia , Farmacorresistência Bacteriana Múltipla , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Nanotecnologia , Penicillium/metabolismo , Prata/metabolismo
11.
Biomed Pharmacother ; 106: 1188-1194, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30119187

RESUMO

Gentamicin is an aminoglycoside antibiotic widely used for the treatment of life-threatening infections caused by Gram-negative bacteria. The use of gentamicin was limited due to its ototoxic and nephrotoxic adverse effects. The current study was designed to evaluate the protective effect of ethyl acetate fraction from Rotula aquatica (EFRA) against gentamicin induced nephrotoxicity. The antioxidant enzymes status, lipid peroxidation, nitrate and ROS level, serum markers like creatinine, Urea, BUN were estimated in the present study. The histopathological analysis of renal tissues was done by H&E and PAS staining. The mRNA level expression of KIM-1, NF-κB, TNF- α, and IL-6 were measured by semi-quantitative reverse transcription-polymerase chain reaction. The changes in antioxidant parameters were restored by the treatment of EFRA at different dose (50 mg/kg bwt, 100 mg/kg bwt). The serum parameters, ROS, MDA and nitrate level were decreased by administration of EFRA. The EFRA ameliorates histological changes associated with gentamicin induced nephrotoxicity. The mRNA level expression of KIM-1, NF-κB, TNF- α, and IL-6 were downregulated in EFRA treated groups. The results from present study reveals the role of EFRA as good anti-inflammatory and nephro protective drug.


Assuntos
Antioxidantes/farmacologia , Boraginaceae , Gentamicinas , Nefropatias/prevenção & controle , Rim/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Antioxidantes/isolamento & purificação , Biomarcadores/metabolismo , Boraginaceae/química , Citoproteção , Modelos Animais de Doenças , Enzimas/metabolismo , Feminino , Regulação da Expressão Gênica , Mediadores da Inflamação/metabolismo , Rim/metabolismo , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Nefropatias/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
12.
Pathophysiology ; 25(4): 381-387, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30032909

RESUMO

The current study aims to the detection of pathogenic potential and virulence factor identification of uropathogenic Escherichia coli BRL-17 isolated from patients urine. The organism was isolated from the patient with chronic pyelonephritis. The identification of organism was done by analyzing gram staining, biochemical, 16S rDNA analysis, Raman microscopy and SEM analysis. The pathogenic potential was identified by multiplex PCR analysis of virulence factor genes like sfa, hly D, pap C. The biofilm forming ability was tested by congo red agar assay and tissue culture plate assay. The result of gram staining and biochemical analysis shows the characteristics of E-coli. The 16S rDNA analysis of the clinically isolated uropathogen showed 100% similarity with uropathogenic Escherichia coli strain. Raman microscopy and SEM confirms the organism as E-coli. The Multiplex PCR study identifies virulence genes like sfa, hly D, pap C in isolated E-coli. The presence of P fimbriae coded pap C gene, S fimbriae coded sfa gene and hemolysin-D coded hly D gene discloses its potential to cause urinary tract infection. Biofilm assay result enhances the organism's role as strong biofilm former. This biofilm forming ability of Escherichia coli strain BRL-17 made the organism to escape from host immune system and helps to colonize in bladder and kidney. This also helps to enhance the resistance to antibiotics. Our study confirms the organism as multidrug resistant, highly virulent, strong biofilm forming E-coli. The strain may be used for the development of animal models of pyelonephritis for the purpose of drug discovery.

13.
Sensors (Basel) ; 18(7)2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29949916

RESUMO

This work presents a visual information fusion approach for robust probability-oriented feature matching. It is sustained by omnidirectional imaging, and it is tested in a visual localization framework, in mobile robotics. General visual localization methods have been extensively studied and optimized in terms of performance. However, one of the main threats that jeopardizes the final estimation is the presence of outliers. In this paper, we present several contributions to deal with that issue. First, 3D information data, associated with SURF (Speeded-Up Robust Feature) points detected on the images, is inferred under the Bayesian framework established by Gaussian processes (GPs). Such information represents a probability distribution for the feature points’ existence, which is successively fused and updated throughout the robot’s poses. Secondly, this distribution can be properly sampled and projected onto the next 2D image frame in t+1, by means of a filter-motion prediction. This strategy permits obtaining relevant areas in the image reference system, from which probable matches could be detected, in terms of the accumulated probability of feature existence. This approach entails an adaptive probability-oriented matching search, which accounts for significant areas of the image, but it also considers unseen parts of the scene, thanks to an internal modulation of the probability distribution domain, computed in terms of the current uncertainty of the system. The main outcomes confirm a robust feature matching, which permits producing consistent localization estimates, aided by the odometer’s prior to estimate the scale factor. Publicly available datasets have been used to validate the design and operation of the approach. Moreover, the proposal has been compared, firstly with a standard feature matching and secondly with a localization method, based on an inverse depth parametrization. The results confirm the validity of the approach in terms of feature matching, localization accuracy, and time consumption.

14.
JMIR Rehabil Assist Technol ; 5(1): e4, 2018 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-29581093

RESUMO

BACKGROUND: Neurological patients after stroke usually present cognitive deficits that cause dependencies in their daily living. These deficits mainly affect the performance of some of their daily activities. For that reason, stroke patients need long-term processes for their cognitive rehabilitation. Considering that classical techniques are focused on acting as guides and are dependent on help from therapists, significant efforts are being made to improve current methodologies and to use eHealth and Web-based architectures to implement information and communication technology (ICT) systems that achieve reliable, personalized, and home-based platforms to increase efficiency and level of attractiveness for patients and carers. OBJECTIVE: The goal of this work was to provide an overview of the practices implemented for the assessment of stroke patients and cognitive rehabilitation. This study puts together traditional methods and the most recent personalized platforms based on ICT technologies and Internet of Things. METHODS: A literature review has been distributed to a multidisciplinary team of researchers from engineering, psychology, and sport science fields. The systematic review has been focused on published scientific research, other European projects, and the most current innovative large-scale initiatives in the area. A total of 3469 results were retrieved from Web of Science, 284 studies from Journal of Medical Internet Research, and 15 European research projects from Community Research and Development Information Service from the last 15 years were reviewed for classification and selection regarding their relevance. RESULTS: A total of 7 relevant studies on the screening of stroke patients have been presented with 6 additional methods for the analysis of kinematics and 9 studies on the execution of goal-oriented activities. Meanwhile, the classical methods to provide cognitive rehabilitation have been classified in the 5 main techniques implemented. Finally, the review has been finalized with the selection of 8 different ICT-based approaches found in scientific-technical studies, 9 European projects funded by the European Commission that offer eHealth architectures, and other large-scale activities such as smart houses and the initiative City4Age. CONCLUSIONS: Stroke is one of the main causes that most negatively affect countries in the socioeconomic aspect. The design of new ICT-based systems should provide 4 main features for an efficient and personalized cognitive rehabilitation: support in the execution of complex daily tasks, automatic error detection, home-based performance, and accessibility. Only 33% of the European projects presented fulfilled those requirements at the same time. For this reason, current and future large-scale initiatives focused on eHealth and smart environments should try to solve this situation by providing more complete and sophisticated platforms.

15.
J Photochem Photobiol B ; 180: 175-185, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29453129

RESUMO

The green synthesis of silver nanoparticles (AgNPs) using biological systems such as fungi has evolved to become an important area of nanobiotechnology. Herein, we report for the first time the light-induced extracellular synthesis of silver nanoparticles using algicolous endophytic fungus Penicillium polonicum ARA 10, isolated from the marine green alga Chetomorpha antennina. Parametric optimization, including the concentration of AgNO3, fungal biomass, ratio of cell filtrate and AgNO3, pH, reaction time and presence of light, was done for rapid AgNPs production. The obtained silver nanoparticles (AgNPs) were characterized by UV-Visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and Transmission electron microscopy (HRTEM-EDAX). The AgNPs showed a characteristic UV-visible peak at 430 nm with an average size of 10-15 nm. The NH stretches in FTIR indicate the presence of protein molecules. The Raman vibrational bands suggest that the molecules responsible for the reduction and stability of AgNPs were extracellular proteins produced by P.polonicum. Antibacterial evaluation of AgNPs against the major foodborne bacterial pathogen Salmonella enterica serovar Typhimurium MTCC 1251, was assessed by well diffusion, Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assay. Killing kinetic studies revealed complete killing of the bacterial cells within 4 h and the bactericidal nature of synthesized nanoparticles was confirmed by fluorescent microscopy and scanning electron microscopy. Furthermore, the bactericidal studies with Transmission electron microscopy (TEM) at different time intervals explored the presence of AgNPs in the cell wall of S.Typhimurium at about 30 min and the complete bacterial lysis was found at 24 h. The current research opens an insight into the green synthesis of AgNPs and the mechanism of bacterial lysis by direct damage to the cell wall.


Assuntos
Antibacterianos/farmacologia , Clorófitas/microbiologia , Luz , Nanopartículas Metálicas/química , Penicillium/química , Salmonella typhimurium/efeitos dos fármacos , Prata/química , Antibacterianos/síntese química , Química Verde , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Penicillium/metabolismo , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
16.
Microb Pathog ; 116: 263-272, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29366864

RESUMO

Acinetobacter baumanii, a gram-negative, non-motile, encapsulated coccobacillus which causes infections worldwide. The objective of this study was to find a fungal strain that could be utilized to biosynthesize antibacterial silver nanoparticles (AgNPs) against Acinetobacter baumanii. The present investigation explains rapid and extracellular biosynthesis of silver nanoparticles by the algicolous endophytic fungus, Penicillium polonicum, isolated from the marine green alga Chetomorpha antennina. The obtained silver nanoparticles were characterized by UV-Vis spectroscopy, Raman spectroscopy, Fourier transformation infrared (FTIR), and Transmission electron microscopy (TEM). The SNPs showed a characteristic UV- visible peak at 430 nm with an average size of 10-15 nm. As evident from the FTIR and Raman spectra, possibly the protein components of fungal extract have caused the reduction of silver nitrate. Parametric optimization, including the concentration of AgNO3, ratio of cell filtrate and AgNO3, fungal biomass, reaction time, pH, and presence of light, was done for rapid AgNPs production. The antibacterial efficacy of AgNPs against multi-drug-resistant, biofilm-forming Acinetobacter baumanii, was evaluated by well diffusion assay. The Minimum inhibitory concentration (MIC) of AgNP was 15.62 µgml-1 and the minimum bactericidal concentration (MBC) was 31.24 µgml-1. Killing kinetic assay revealed complete killing of the bacterial cells within 6 h. Log reduction and percent survival of bacterial cells were analyzed from killing kinetic study. Bactericidal nature of synthesized nanoparticles was confirmed by fluorescent microscopical analysis. The effect of AgNPs on the ultrastructure of bacterial pathogen was evaluated by Transmission electron microscopy.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/metabolismo , Biofilmes/crescimento & desenvolvimento , Nanopartículas Metálicas , Penicillium/metabolismo , Prata/metabolismo , Acinetobacter baumannii/fisiologia , Antibacterianos/farmacologia , Clorófitas/microbiologia , Contagem de Colônia Microbiana , Farmacorresistência Bacteriana Múltipla , Endófitos/isolamento & purificação , Endófitos/metabolismo , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Penicillium/isolamento & purificação , Prata/farmacologia , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
17.
AIDS Behav ; 22(1): 287-296, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28074421

RESUMO

We conducted a cluster-randomized trial to estimate effects of directly observed combination antiretroviral therapy (DOT-cART) on retention with viral suppression among HIV-positive adults in Peru. We randomly allocated facilities to receive the 12-month intervention plus the standard of care, including adherence support provided through accompaniment. In the intervention arm, health workers supervised doses, twice daily, and accompanied patients to appointments. Among 356 patients, intention-to-treat analyses showed no statistically significant benefit of DOT, relative to no-DOT, at 12 or 24 months (adjusted probability of primary outcome: 0.81 vs. 0.73 and 0.76 vs. 0.68, respectively). A statistically significant benefit of DOT was found in per-protocol and as-treated analyses at 12 months (0.83 for DOT vs. 0.73 for no DOT, p value: 0.02 per-protocol, 0.01 as-treated), but not 24 months. Rates of retention with viral suppression were high in both arms. Among adults receiving robust adherence support, the added effect of time-limited DOT, if any, is small-to-moderate.


Assuntos
Terapia Antirretroviral de Alta Atividade/métodos , Serviços de Saúde Comunitária , Terapia Diretamente Observada , Infecções por HIV/tratamento farmacológico , Carga Viral/efeitos dos fármacos , Adulto , Terapia Antirretroviral de Alta Atividade/psicologia , Agendamento de Consultas , Prestação Integrada de Cuidados de Saúde/organização & administração , Feminino , Infecções por HIV/psicologia , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Peru , Retenção nos Cuidados , Apoio Social , Resultado do Tratamento
18.
PLoS Genet ; 13(6): e1006841, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28644860

RESUMO

Vertical growth of plants is a dynamic process that is influenced by genetic and environmental factors and has a pronounced effect on overall plant architecture and biomass composition. We have performed six controlled growth trials of an interspecific Setaria italica x Setaria viridis recombinant inbred line population to assess how the genetic architecture of plant height is influenced by developmental queues, water availability and planting density. The non-destructive nature of plant height measurements has enabled us to monitor height throughout the plant life cycle in both field and controlled environments. We find that plant height is reduced under water limitation and high density planting and affected by growth environment (field vs. growth chamber). The results support a model where plant height is a heritable, polygenic trait and that the major genetic loci that influence plant height function independent of growth environment. The identity and contribution of loci that influence height changes dynamically throughout development and the reduction of growth observed in water limited environments is a consequence of delayed progression through the genetic program which establishes plant height in Setaria. In this population, alleles inherited from the weedy S. viridis parent act to increase plant height early, whereas a larger number of small effect alleles inherited from the domesticated S. italica parent collectively act to increase plant height later in development.


Assuntos
Ambiente Controlado , Locos de Características Quantitativas/genética , Setaria (Planta)/genética , Alelos , Biomassa , Mapeamento Cromossômico , Genoma de Planta , Genótipo , Herança Multifatorial/genética , Fenótipo , Setaria (Planta)/crescimento & desenvolvimento
19.
Proc Natl Acad Sci U S A ; 113(31): 8861-6, 2016 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-27422554

RESUMO

Many important crops are members of the Poaceae family, which develop root systems characterized by a high degree of root initiation from the belowground basal nodes of the shoot, termed the crown. Although this postembryonic shoot-borne root system represents the major conduit for water uptake, little is known about the effect of water availability on its development. Here we demonstrate that in the model C4 grass Setaria viridis, the crown locally senses water availability and suppresses postemergence crown root growth under a water deficit. This response was observed in field and growth room environments and in all grass species tested. Luminescence-based imaging of root systems grown in soil-like media revealed a shift in root growth from crown-derived to primary root-derived branches, suggesting that primary root-dominated architecture can be induced in S. viridis under certain stress conditions. Crown roots of Zea mays and Setaria italica, domesticated relatives of teosinte and S. viridis, respectively, show reduced sensitivity to water deficit, suggesting that this response might have been influenced by human selection. Enhanced water status of maize mutants lacking crown roots suggests that under a water deficit, stronger suppression of crown roots actually may benefit crop productivity.


Assuntos
Secas , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento , Poaceae/crescimento & desenvolvimento , Água/metabolismo , Mutação , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/metabolismo , Poaceae/genética , Poaceae/metabolismo , Setaria (Planta)/genética , Setaria (Planta)/crescimento & desenvolvimento , Setaria (Planta)/metabolismo , Solo , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
20.
PLoS One ; 11(5): e0155436, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27187800

RESUMO

OBJECTIVE: To apply a fully automated method to quantify the 3D structure of the bony nasolacrimal canal (NLC) from CT scans whereby the size and main morphometric characteristics of the canal can be determined. DESIGN: Cross-sectional study. SUBJECTS: 36 eyes of 18 healthy individuals. METHODS: Using software designed to detect the boundaries of the NLC on CT images, 36 NLC reconstructions were prepared. These reconstructions were then used to calculate NLC volume. The NLC axis in each case was determined according to a polygonal model and to 2nd, 3rd and 4th degree polynomials. From these models, NLC sectional areas and length were determined. For each variable, descriptive statistics and normality tests (Kolmogorov-Smirnov and Shapiro-Wilk) were established. MAIN OUTCOME MEASURES: Time for segmentation, NLC volume, axis, sectional areas and length. RESULTS: Mean processing time was around 30 seconds for segmenting each canal. All the variables generated were normally distributed. Measurements obtained using the four models polygonal, 2nd, 3rd and 4th degree polynomial, respectively, were: mean canal length 14.74, 14.3, 14.80, and 15.03 mm; mean sectional area 15.15, 11.77, 11.43, and 11.56 mm2; minimum sectional area 8.69, 7.62, 7.40, and 7.19 mm2; and mean depth of minimum sectional area (craniocaudal) 7.85, 7.71, 8.19, and 8.08 mm. CONCLUSION: The method proposed automatically reconstructs the NLC on CT scans. Using these reconstructions, morphometric measurements can be calculated from NLC axis estimates based on polygonal and 2nd, 3rd and 4th polynomial models.


Assuntos
Osso e Ossos/cirurgia , Imageamento Tridimensional , Ducto Nasolacrimal/cirurgia , Cirurgia Assistida por Computador , Tomografia Computadorizada por Raios X , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Anatômicos
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