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1.
Nature ; 618(7964): 276-280, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37225991

RESUMO

Photoinjection of charge carriers profoundly changes the properties of a solid. This manipulation enables ultrafast measurements, such as electric-field sampling1,2, advanced recently to petahertz frequencies3-7, and the real-time study of many-body physics8-13. Nonlinear photoexcitation by a few-cycle laser pulse can be confined to its strongest half-cycle14-16. Describing the associated subcycle optical response, vital for attosecond-scale optoelectronics, is elusive when studied with traditional pump-probe metrology as the dynamics distort any probing field on the timescale of the carrier, rather than that of the envelope. Here we apply field-resolved optical metrology to these dynamics and report the direct observation of the evolving optical properties of silicon and silica during the first few femtoseconds following a near-1-fs carrier injection. We observe that the Drude-Lorentz response forms within several femtoseconds-a time interval much shorter than the inverse plasma frequency. This is in contrast to previous measurements in the terahertz domain8,9 and central to the quest to speed up electron-based signal processing.

2.
Brief Bioinform ; 24(3)2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37031957

RESUMO

Network pharmacology is an emerging area of systematic drug research that attempts to understand drug actions and interactions with multiple targets. Network pharmacology has changed the paradigm from 'one-target one-drug' to highly potent 'multi-target drug'. Despite that, this synergistic approach is currently facing many challenges particularly mining effective information such as drug targets, mechanism of action, and drug and organism interaction from massive, heterogeneous data. To overcome bottlenecks in multi-target drug discovery, computational algorithms are highly welcomed by scientific community. Machine learning (ML) and especially its subfield deep learning (DL) have seen impressive advances. Techniques developed within these fields are now able to analyze and learn from huge amounts of data in disparate formats. In terms of network pharmacology, ML can improve discovery and decision making from big data. Opportunities to apply ML occur in all stages of network pharmacology research. Examples include screening of biologically active small molecules, target identification, metabolic pathways identification, protein-protein interaction network analysis, hub gene analysis and finding binding affinity between compounds and target proteins. This review summarizes the premier algorithmic concepts of ML in network pharmacology and forecasts future opportunities, potential applications as well as several remaining challenges of implementing ML in network pharmacology. To our knowledge, this study provides the first comprehensive assessment of ML approaches in network pharmacology, and we hope that it encourages additional efforts toward the development and acceptance of network pharmacology in the pharmaceutical industry.


Assuntos
Farmacologia em Rede , Farmacologia , Descoberta de Drogas/métodos , Aprendizado de Máquina , Proteínas , Algoritmos , Farmacologia/métodos
3.
Genet Epidemiol ; 47(1): 105-118, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36352773

RESUMO

The minor allele of rs373863828, a missense variant in CREB3 Regulatory Factor, is associated with several cardiometabolic phenotypes in Polynesian peoples. To better understand the variant, we tested the association of rs373863828 with a panel of correlated phenotypes (body mass index [BMI], weight, height, HDL cholesterol, triglycerides, and total cholesterol) using multivariate Bayesian association and network analyses in a Samoa cohort (n = 1632), Aotearoa New Zealand cohort (n = 1419), and combined cohort (n = 2976). An expanded set of phenotypes (adding estimated fat and fat-free mass, abdominal circumference, hip circumference, and abdominal-hip ratio) was tested in the Samoa cohort (n = 1496). In the Samoa cohort, we observed significant associations (log10 Bayes Factor [BF] ≥ 5.0) between rs373863828 and the overall phenotype panel (8.81), weight (8.30), and BMI (6.42). In the Aotearoa New Zealand cohort, we observed suggestive associations (1.5 < log10 BF < 5) between rs373863828 and the overall phenotype panel (4.60), weight (3.27), and BMI (1.80). In the combined cohort, we observed concordant signals with larger log10 BFs. In the Samoa-specific expanded phenotype analyses, we also observed significant associations between rs373863828 and fat mass (5.65), abdominal circumference (5.34), and hip circumference (5.09). Bayesian networks provided evidence for a direct association of rs373863828 with weight and indirect associations with height and BMI.


Assuntos
Adiposidade , População das Ilhas do Pacífico , Proteínas Supressoras de Tumor , Humanos , Teorema de Bayes , Índice de Massa Corporal , Análise Multivariada , Obesidade/genética , Proteínas Supressoras de Tumor/genética , Mutação de Sentido Incorreto
4.
Microb Pathog ; 189: 106599, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428471

RESUMO

We have functionally evaluated a transcription factor CaMYB59 for its role in pepper immune responses to Ralstonia solanacearum attack and high temperature-high humidity (HTHH). Exposure to R. solanacearum inoculation (RSI) and HTHH resulted in up-regulation of this nucleus-localized TF. Function of this TF was confirmed by performing loss of function assay of CaMYB59 by VIGS (virus-induced gene silencing). Plants with silenced CaMYB59 displayed not only compromised pepper immunity against RSI but also impaired tolerance to HTHH along with decreased hypersensitive response (HR). This impairment in defense function was fully linked with low induction of stress-linked genes like CaPO2, CaPR1, CaAcc and thermo-tolerance linked CaHSP24 as well as CaHsfB2a. Conversely, transient overexpression of CaMYB59 enhanced pepper immunity. This reveals that CaMYB59 positively regulated host defense against RSI and HTHH by means of HR like mimic cell death, H2O2 production and up-regulation of defense as well as thermo-tolerance associated genes. These changes in attributes collectively confirm the role of CaMYB59 as a positive regulator of pepper immunity against R. solanacearum. We recommend that such positive regulation of pepper defense is dynamically supported by phyto-hormone signaling and transcriptional web of defense genes. These integrated and interlinked events stabilize plant growth and survival under abiotic and biotic stresses.


Assuntos
Reguladores de Crescimento de Plantas , Ralstonia solanacearum , Humanos , Reguladores de Crescimento de Plantas/genética , Resistência à Doença/genética , Imunidade Vegetal/genética , Ralstonia solanacearum/genética , Peróxido de Hidrogênio/metabolismo , Temperatura , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Doenças das Plantas/genética
5.
J Clin Densitom ; 27(2): 101471, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306806

RESUMO

Osteoporosis is characterised by the loss of bone density resulting in an increased risk of fragility fractures. The clinical gold standard for diagnosing osteoporosis is based on the areal bone mineral density (aBMD) used as a surrogate for bone strength, in combination with clinical risk factors. Finite element (FE) analyses based on quantitative computed tomography (QCT) have been shown to estimate bone strength better than aBMD. However, their application in the osteoporosis clinics is limited due to exposure of patients to increased X-rays radiation dose. Statistical modelling methods (3D-DXA) enabling the estimation of 3D femur shape and volumetric bone density from dual energy X-ray absorptiometry (DXA) scan have been shown to improve osteoporosis management. The current study used 3D-DXA based FE analyses to estimate femur strength from the routine clinical DXA scans and compared its results against 151 QCT based FE analyses, in a clinical cohort of 157 subjects. The linear regression between the femur strength predicted by QCT-FE and 3D-DXA-FE models correlated highly (coefficient of determination R2 = 0.86) with a root mean square error (RMSE) of 397 N. In conclusion, the current study presented a 3D-DXA-FE modelling tool providing accurate femur strength estimates noninvasively, compared to QCT-FE models.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Fêmur , Análise de Elementos Finitos , Imageamento Tridimensional , Tomografia Computadorizada por Raios X , Humanos , Fêmur/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Feminino , Idoso , Pessoa de Meia-Idade , Masculino , Osteoporose/diagnóstico por imagem , Osteoporose/fisiopatologia , Idoso de 80 Anos ou mais
6.
Mol Genet Genomics ; 298(1): 79-93, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36301366

RESUMO

Salinity severely affects crop yield by hindering nitrogen uptake and reducing plant growth. Plant growth-promoting bacteria (PGPB) are capable of providing cross-protection against biotic/abiotic stresses and facilitating plant growth. Genome-level knowledge of PGPB is necessary to translate the knowledge into a product as efficient biofertilizers and biocontrol agents. The current study aimed to isolate and characterize indigenous plant growth-promoting strains with the potential to promote plant growth under various stress conditions. In this regard, 72 bacterial strains were isolated from various saline-sodic soil/lakes; 19 exhibited multiple in vitro plant growth-promoting traits, including indole 3 acetic acid production, phosphate solubilization, siderophore synthesis, lytic enzymes production, biofilm formation, and antibacterial activities. To get an in-depth insight into genome composition and diversity, whole-genome sequence and genome mining of one promising Bacillus paralicheniformis strain ES-1 were performed. The strain ES-1 genome carries 12 biosynthetic gene clusters, at least six genomic islands, and four prophage regions. Genome mining identified plant growth-promoting conferring genes such as phosphate solubilization, nitrogen fixation, tryptophan production, siderophore, acetoin, butanediol, chitinase, hydrogen sulfate synthesis, chemotaxis, and motility. Comparative genome analysis indicates the region of genome plasticity which shapes the structure and function of B. paralicheniformis and plays a crucial role in habitat adaptation. The strain ES-1 has a relatively large accessory genome of 649 genes (~ 19%) and 180 unique genes. Overall, these results provide valuable insight into the bioactivity and genomic insight into B. paralicheniformis strain ES-1 with its potential use in sustainable agriculture.


Assuntos
Bacillus , Sideróforos , Sideróforos/genética , Bacillus/genética , Bactérias/genética , Cloreto de Sódio , Antibacterianos , Fosfatos/farmacologia
7.
J Hum Genet ; 68(7): 463-468, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36864286

RESUMO

The fat mass and obesity associated (FTO) locus consistently associates with higher body mass index (BMI) across diverse ancestral groups. However, previous small studies of people of Polynesian ancestries have failed to replicate the association. In this study, we used Bayesian meta-analysis to test rs9939609, the most replicated FTO variant, for association with BMI with a large sample (n = 6095) of Aotearoa New Zealanders of Polynesian (Maori and Pacific) ancestry and of Samoan people living in the Independent State of Samoa and in American Samoa. We did not observe statistically significant association within each separate Polynesian subgroup. Bayesian meta-analysis of the Aotearoa New Zealand Polynesian and Samoan samples resulted in a posterior mean effect size estimate of +0.21 kg/m2, with a 95% credible interval [+0.03 kg/m2, +0.39 kg/m2]. While the Bayes Factor (BF) of 0.77 weakly favors the null, the BF = 1.4 Bayesian support interval is [+0.04, +0.20]. These results suggest that rs9939609 in FTO may have a similar effect on mean BMI in people of Polynesian ancestries as previously observed in other ancestral groups.


Assuntos
Índice de Massa Corporal , Povo Maori , População das Ilhas do Pacífico , Humanos , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Teorema de Bayes , Predisposição Genética para Doença , Povo Maori/genética , Nova Zelândia , População das Ilhas do Pacífico/genética , Polimorfismo de Nucleotídeo Único
8.
Theor Appl Genet ; 136(12): 256, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38010528

RESUMO

KEY MESSAGE: By integrating QTL fine mapping and transcriptomics, a candidate gene responsible for oil content in rapeseed was identified. The gene is anticipated to primarily function in photosynthesis and photosystem metabolism pathways. Brassica napus is one of the most important oil crops in the world, and enhancing seed oil content is an important goal in its genetic improvement. However, the underlying genetic basis for the important trait remains poorly understood in this crop. We previously identified a major locus, OILA5 responsible for seed oil content on chromosome A5 through genome-wide association study. To better understand the genetics of the QTL, we performed fine mapping of OILA5 with a double haploid population and a BC3F2 segregation population consisting of 6227 individuals. We narrowed down the QTL to an approximate 43 kb region with twelve annotated genes, flanked by markers ZDM389 and ZDM337. To unveil the potential candidate gene responsible for OILA5, we integrated fine mapping data with transcriptome profiling using high and low oil content near-isogenic lines. Among the candidate genes, BnaA05G0439400ZS was identified with high expression levels in both seed and silique tissues. This gene exhibited homology with AT3G09840 in Arabidopsis that was annotated as cell division cycle 48. We designed a site-specific marker based on resequencing data and confirmed its effectiveness in both natural and segregating populations. Our comprehensive results provide valuable genetic information not only enhancing our understanding of the genetic control of seed oil content but also novel germplasm for advancing high seed oil content breeding in B. napus and other oil crops.


Assuntos
Brassica napus , Humanos , Brassica napus/genética , Brassica napus/metabolismo , Locos de Características Quantitativas , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Sementes/química , Óleos de Plantas/análise
9.
Arch Microbiol ; 205(5): 175, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37027063

RESUMO

Shigellosis is the main cause of food and waterborne diarrhea and is an emerging threat to human health. The current study characterized the indigenous multidrug-resistant Shigella flexneri serotypes for their plasmid profiles and genetic diversity, to characterize the plasmid evolutionary patterns and distribution. In total, 199 identified S. flexneri isolates belonging to six different serotypes were analyzed for plasmid profiling, followed by an analysis of whole genome sequencing. All isolates of S. flexneri resistant to antibiotics harbored multiple copies of plasmids with sizes ranging from 1.25 kbp to 9.4 kbp. These isolates were clustered into 22 distinct plasmid patterns, labeled as p1-p22. Among these, p1 (24%) and p10 (13%) were the predominant plasmid profiles. All S. flexneri strains were grouped into 12 clades with a 75% similarity level. Also, a significant association was observed among the plasmid patterns, p23 and p17 with the drug-resistant patterns AMC, SXT, C (19.5%) and OFX, AMC, NA, CIP (13.5%), respectively. Moreover, the most widespread plasmid patterns p4, p10, and p1 showed a significant association with the serotypes 1b (29.16%), 2b (36%), and 7a (100%), respectively. After plasmid sequence assembly and annotation analysis, a variety of small plasmids that vary in size from 973 to 6200 bp were discovered. Many of these plasmids displayed high homology and coverage with plasmids from non-S. flexneri. Several novel plasmids of small size were discovered in multidrug-resistant S. flexneri. The data also showed that plasmid profile analysis is more consistent than antibiotic susceptibility pattern analysis for identifying epidemic strains of S. flexneri isolated in Pakistan.


Assuntos
Antibacterianos , Shigella flexneri , Humanos , Shigella flexneri/genética , Sorogrupo , Paquistão , Plasmídeos/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
10.
Nephrol Dial Transplant ; 38(5): 1297-1308, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-36243955

RESUMO

BACKGROUND: Frailty among haemodialysis patients is associated with hospitalization and mortality, but high frailty prevalence suggests further discrimination of risk is required. We hypothesized that incorporation of self-reported health with frailty measurement may aid risk stratification. METHODS: Prospective cohort study of 485 prevalent haemodialysis recipients linked to English national datasets. Frailty Phenotype (FP), Frailty Index (FI), Edmonton Frail Scale (EFS), Clinical Frailty Scale (CFS) and self-reported health change were assessed. Mortality was explored using Fine and Gray regression, and admissions by negative binomial regression. RESULTS: Over a median 678 (interquartile range 531-812) days, there were 111 deaths, and 1241 hospitalizations. Increasing frailty was associated with mortality on adjusted analyses for FP [subdistribution hazard ratio (SHR) 1.26, 95% confidence interval (CI) 1.05-1.53, P = .01], FI (SHR 1.21, 95% CI 1.09-1.35, P = .001) and CFS (SHR 1.32, 95% CI 1.11-1.58, P = .002), but not EFS (HR 1.08, 95% CI 0.99-1.18, P = .1). Health change interacted with frailty tools to modify association with mortality; only those who rated their health as the same or worse experienced increased mortality hazard associated with frailty by FP (Pinteraction = .001 and 0.035, respectively), FI (Pinteraction = .002 and .007, respectively) and CFS (Pinteraction = .009 and 0.02, respectively). CFS was the only frailty tool associated with hospitalization (incidence rate ratio 1.12, 95% CI 1.02-1.23, P = .02). CONCLUSIONS: We confirm the high burden of hospitalization and mortality associated with haemodialysis patients regardless of frailty tool utilized and introduce the discriminatory ability of self-reported health to identify the most at-risk frail individuals.


Assuntos
Fragilidade , Humanos , Idoso , Fragilidade/epidemiologia , Fragilidade/etiologia , Estudos Prospectivos , Idoso Fragilizado , Autorrelato , Hospitalização , Diálise Renal/efeitos adversos , Hospitais , Reino Unido/epidemiologia , Avaliação Geriátrica
11.
J Opt Soc Am A Opt Image Sci Vis ; 40(6): 1183-1190, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706771

RESUMO

In this paper, a broadband multi-layered active metamaterial design is investigated, which can achieve a high polarization conversion efficiency over a wide band of frequencies in the terahertz regime. The design can be switched to an efficient metamaterial absorber using the phase transition property of vanadium dioxide (V O 2). Additionally, the designed structure can convert the linear polarization of the incoming wavefronts to its cross-polarization and linear polarization to circular polarization in the reflection mode. The broadband characteristic is achieved due to the strong anisotropic behavior of the metasurface. The structure is robust to a wide range of incident angles as well. The proposed switchable multifunctional design can contribute to the development of active plasmonic polarization devices and metamaterial absorbers.

12.
BMC Nephrol ; 24(1): 80, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36997856

RESUMO

BACKGROUND: The Clinical Frailty Scale (CFS) is a commonly utilised frailty screening tool that has been associated with hospitalisation and mortality in haemodialysis recipients, but is subject to heterogenous methodologies including subjective clinician opinion. The aims of this study were to (i) examine the accuracy of a subjective, multidisciplinary assessment of CFS at haemodialysis Quality Assurance (QA) meetings (CFS-MDT), compared with a standard CFS score via clinical interview, and (ii) ascertain the associations of these scores with hospitalisation and mortality. METHODS: We performed a prospective cohort study of prevalent haemodialysis recipients linked to national datasets for outcomes including mortality and hospitalisation. Frailty was assessed using the CFS after structured clinical interview. The CFS-MDT was derived from consensus at haemodialysis QA meetings, involving dialysis nurses, dietitians, and nephrologists. RESULTS: 453 participants were followed-up for a median of 685 days (IQR 544-812), during which there were 96 (21.2%) deaths and 1136 hospitalisations shared between 327 (72.1%) participants. Frailty was identified in 246 (54.3%) participants via CFS, but only 120 (26.5%) via CFS-MDT. There was weak correlation (Spearman Rho 0.485, P < 0.001) on raw frailty scores and minimal agreement (Cohen's κ = 0.274, P < 0.001) on categorisation of frail, vulnerable and robust between the CFS and CFS-MDT. Increasing frailty was associated with higher rates of hospitalisation for the CFS (IRR 1.26, 95% C.I. 1.17-1.36, P = 0.016) and CFS-MDT (IRR 1.10, 1.02-1.19, P = 0.02), but only the CFS-MDT was associated with nights spent in hospital (IRR 1.22, 95% C.I. 1.08-1.38, P = 0.001). Both scores were associated with mortality (CFS HR 1.31, 95% C.I. 1.09-1.57, P = 0.004; CFS-MDT HR 1.36, 95% C.I. 1.16-1.59, P < 0.001). CONCLUSIONS: Assessment of CFS is deeply affected by the underlying methodology, with the potential to profoundly affect decision-making. The CFS-MDT appears to be a weak alternative to conventional CFS. Standardisation of CFS use is of paramount importance in clinical and research practice in haemodialysis. TRIAL REGISTRATION: Clinicaltrials.gov : NCT03071107 registered 06/03/2017.


Assuntos
Fragilidade , Diálise Renal , Humanos , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Hospitalização , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
BMC Nephrol ; 24(1): 16, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36653750

RESUMO

BACKGROUND: Ultrasonographic quantitation of quadriceps muscle mass is increasingly used for assessment of sarcopenia, but its relationship with frailty in haemodialysis recipients is not known. This study explores the relationship between ultrasound-derived bilateral anterior thigh thickness (BATT), sarcopenia, and frailty by common frailty tools (Frailty Phenotype [FP], Frailty Index [FI], Edmonton Frailty [EFS], and Clinical Frailty Scale [CFS]). METHODS: This was an exploratory analysis of a subgroup of adult prevalent (≥3 months) haemodialysis recipients deeply phenotyped for frailty. Ultrasound assessment of BATT was obtained with participants at an angle of ≤45°, with legs outstretched and knees resting at 10°-20°, according to an established protocol. Associations with frailty were explored via both linear and logistic regressions for BATT, Low Muscle Mass (LMM), and sarcopenia with stepwise adjustment for a priori covariables. RESULTS: In total 223 study participants had ultrasound measurements. Frailty ranged from 34% for FP to 58% for FI. BATT was associated with increasing frailty on simple linear regression by all frailty tools, but lost significance on addition of covariables. Upon dichotomising frailty tools into Frail/Not Frail, BATT was associated with frailty by all tools on univariable analyses, but only retained association for EFS on the fully adjusted model (OR 0.97, 95% C.I. 0.94-1.00, P = 0.05). CONCLUSIONS: Ultrasound measures of quadriceps thickness is variably associated with frailty in prevalent haemodialysis recipients, dependent upon the frailty tool used, but not independent of other variables. Further work is required to establish the added value of sarcopenia measurement in frail haemodialysis patients. TRIAL REGISTRATION: Clinicaltrials.gov : NCT03071107 registered 06/03/2017.


Assuntos
Fragilidade , Sarcopenia , Idoso , Humanos , Idoso Fragilizado , Fragilidade/diagnóstico por imagem , Fragilidade/epidemiologia , Avaliação Geriátrica/métodos , Músculo Quadríceps/diagnóstico por imagem , Diálise Renal/efeitos adversos , Sarcopenia/diagnóstico por imagem
14.
Int J Mol Sci ; 24(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36674532

RESUMO

In this review, we summarize recent work on the "green synthesis" of carbon nanoparticles (CNPs) and their application with a focus on biomedical applications. Recent developments in the green synthesis of carbon nanoparticles, from renewable precursors and their application for environmental, energy-storage and medicinal applications are discussed. CNPs, especially carbon nanotubes (CNTs), carbon quantum dots (CQDs) and graphene, have demonstrated utility as high-density energy storage media, environmental remediation materials and in biomedical applications. Conventional fabrication of CNPs can entail the use of toxic catalysts; therefore, we discuss low-toxicity manufacturing as well as sustainable and environmentally friendly methodology with a focus on utilizing readily available biomass as the precursor for generating CNPs.


Assuntos
Grafite , Nanopartículas , Nanotubos de Carbono , Pontos Quânticos , Nanotubos de Carbono/toxicidade , Biomassa , Catálise
15.
Int J Mol Sci ; 24(5)2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36902415

RESUMO

Rice is one of the staple foods for the majority of the global population that depends directly or indirectly on it. The yield of this important crop is constantly challenged by various biotic stresses. Rice blast, caused by Magnaporthe oryzae (M. oryzae), is a devastating rice disease causing severe yield losses annually and threatening rice production globally. The development of a resistant variety is one of the most effective and economical approaches to control rice blast. Researchers in the past few decades have witnessed the characterization of several qualitative resistance (R) and quantitative resistance (qR) genes to blast disease as well as several avirulence (Avr) genes from the pathogen. These provide great help for either breeders to develop a resistant variety or pathologists to monitor the dynamics of pathogenic isolates, and ultimately to control the disease. Here, we summarize the current status of the isolation of R, qR and Avr genes in the rice-M. oryzae interaction system, and review the progresses and problems of these genes utilized in practice for reducing rice blast disease. Research perspectives towards better managing blast disease by developing a broad-spectrum and durable blast resistance variety and new fungicides are also discussed.


Assuntos
Magnaporthe , Oryza , Resistência à Doença/genética , Virulência/genética , Magnaporthe/genética , Oryza/genética , Doenças das Plantas/genética
16.
World J Microbiol Biotechnol ; 39(5): 132, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36959469

RESUMO

Urinary tract infections (UTIs) are predominantly caused by uropathogenic Escherichia coli (E. coli). There is rapid increase in antimicrobial resistance in UTIs, also declared as a serious health threat by World Health Organization (WHO). Present study was designed to investigate the antimicrobial resistance status with specific focus on ESBLs and carbapenemases in local uropathogenic E. coli (UPEC) isolates. E. coli isolates were characterized from patients of all ages visiting diagnostic laboratories for urine examination. Demographic data was also recorded for each patient. Antibiograms were developed to observe antibiotic resistance in UPEC using Kirby Bauer disc diffusion technique. Double Disc Synergy test (DDST) was used for phenotypic ESBL test. ESBLs and carbapenemases genes were detected in UPEC using PCR. The PCR results were confirmed by sequencing. The UPEC isolates under study exhibited 78%, 77%, 74%, 72% and 55% resistance against cefotaxime, amoxicillin, erythromycin, ceftriaxone and cefixime, respectively. Resistance against colistin and meropenem was observed in 64% and 34% isolates, respectively. Phenotypic DDST identified 48% isolates as ESBLs producers. Genotypic characterization identified 70%, 74.4% and 49% prevalence of CTXM-1, TEM-1 and CTXM-15 genes respectively. One isolate was observed exhibiting co-existence of all ESBL genes. TEM-1 + CTXM-1 and TEM-1 + CTXM-1 + CTXM-15 + OXA-1 gene patterns were dominant among ESBLs. For carbapenem-resistance, 14% isolates indicated the presence of KPC whereas GES and VIM was detected in 7% and 3.4% isolates, respectively. In conclusion, our results present a high prevalence of extensively drug resistant UPEC isolates with a considerable percentage of ESBL producers. These findings propose the need of continuous surveillance for antimicrobial resistance and targeted antimicrobial therapy.


Assuntos
Infecções por Escherichia coli , Infecções Urinárias , Escherichia coli Uropatogênica , Humanos , Escherichia coli Uropatogênica/genética , Infecções por Escherichia coli/epidemiologia , Prevalência , Paquistão , beta-Lactamases/genética , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
17.
Kidney Int ; 102(4): 876-884, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35716956

RESUMO

Major adverse cardiovascular event (MACE) rates immediately after kidney transplantation remain uncertain due to heterogeneous reporting in the literature. To clarify this, we retrospectively studied every eligible kidney transplant procedure performed in England between April 1, 2002 and March 31, 2018, with follow-up through August 31, 2019. The primary outcome of interest was MACE broadly defined as any hospital admission with myocardial infarction, stroke, unstable angina, heart failure, any coronary revascularisation procedure and/or any cardiovascular death. Among 30,325 kidney transplant recipients, MACE occurred in 781 within the first year after transplantation (2.6% of all kidney transplant procedures). Of these 781 events, 201 occurred during the index admission for kidney transplantation surgery representing 25.7% of all first-year MACE and 0.7% of all kidney transplant procedures. Kidney transplant recipients who suffered a non-fatal MACE within the first year had significantly decreased 1-, 3-, 5- and 10-year patient survival of 80.5%, 70.2%, 59.5% and 38.6% respectively, compared to 97.4%, 94.4%, 90.7% and 78.4% for kidney transplant recipients not developing MACE. In an adjusted Cox proportional hazard model, non-fatal MACE within the first-year post-transplant was associated with significant long-term mortality risk (hazard ratio 2.59; 95% confidence interval 2.34-2.88). Kidney transplant recipients experiencing MACE during the index admission compared to subsequent admissions were differentiated by age, sex and previous cardiac history but had similar patient survival. These rates are significantly lower than those reported in North America. Thus, our data confirm MACE is not a benign post-transplant event and has a strong association with long-term mortality risk.


Assuntos
Transplante de Rim , Infarto do Miocárdio , Estudos de Coortes , Humanos , Transplante de Rim/efeitos adversos , Infarto do Miocárdio/epidemiologia , Estudos Retrospectivos , Fatores de Risco
18.
BMC Cancer ; 22(1): 338, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35351051

RESUMO

BACKGROUND: An accurate knowledge of the relocation of prostate neoplasms during biopsy is of great importance to reduce the number of false negative results. Prostate neoplasms are visible in magnetic resonance images (MRI) but it is difficult for the practitioner to locate them at the time of performing a transrectal ultrasound (TRUS) guided biopsy. In this study, we present a new methodology, based on simulation, that predicts both prostate deformation and lesion migration during the biopsy. METHODS: A three-dimensional (3-D) anatomy model of the pelvic region, based on medical images, is constructed. A finite element (FE) numerical simulation of the organs motion and deformation as a result of the pressure exerted by the TRUS probe is carried out using the Code-Aster open-source computer software. Initial positions of potential prostate lesions prior to biopsy are taken into consideration and the final location of each lesion is targeted in the FE simulation output. RESULTS: Our 3-D FE simulations show that the effect of the pressure exerted by the TRUS probe is twofold as the prostate experiences both a motion and a deformation of its original shape. We targeted the relocation of five small prostate lesions when the TRUS probe exerts a force of 30 N on the rectum inner wall. The distance travelled by these lesions ranged between 5.6 and 13.9 mm. CONCLUSIONS: Our new methodology can help to predict the location of neoplasms during a prostate biopsy but further studies are needed to validate our results. Moreover, the new methodology is completely developed on open-source software, which means that its implementation would be affordable to all healthcare providers.


Assuntos
Próstata , Neoplasias da Próstata , Biópsia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pelve/diagnóstico por imagem , Pelve/patologia , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia
19.
Curr Microbiol ; 79(4): 105, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35157141

RESUMO

Curli fimbriae, a virulent factor of the Avian Pathogenic Escherichia coli (APEC), is responsible for adhesion, biofilm formation, and colonization of pathogen. Major curli fimbriae protein is encoded by csgA gene. APEC is one of the leading causes of colibacillosis in poultry flocks and due to excessive use of antibiotics and vaccines in poultry, the emergence of various multi-drug resistant (MDR) bacterial strainsare is frequently reported. The growing concern of MDR bacterial strains necessitate novel antibacterial approaches to combat colibacillosis in poultry. RNA-based gene silencing is a very specific and robust strategy to target specific bacterial factors involved in pathogenicity and virulence. In this study, a phagemid-mediated sRNA expression system to target a vital gene, csgA, is employed. This comprises an M13 phagemid harboring a sRNA expression cassette and a pre-designed GUIDE sequences for the csgA target gene. To target the csgA gene at the mRNA level, a GUIDE sequence was computationally designed for pre-designed sRNA expression cassette. Online web tools were used to predict the binding energy, secondary structure, and off-target binding potential of the sRNA to optimize its expression. Results showed that the designed sRNA has a binding energy of - 29.60 kcal/mol with zero off-targets. After expression of the sRNA in the APEC cells, Ì´ 45% reduction in the csgA level was observed via RT-PCR in the CS-APEC-O1 strains compared to the wt-APEC-O1. Similarly, the biofilm forming ability decreased by 40% in the CS-APEC-O1 strains. The swarming motility and hemagglutination efficiency were not affected by the sRNA expression. Future studies investigating the in vivo efficiency of M13 phagemid delivery are required to evaluate its candidacy in phage therapy.


Assuntos
Infecções por Escherichia coli , Doenças das Aves Domésticas , Animais , Galinhas , Escherichia coli/genética , Infecções por Escherichia coli/veterinária , Virulência/genética , Fatores de Virulência
20.
Curr Microbiol ; 79(4): 118, 2022 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-35220467

RESUMO

The rapid emergence of resistance to third-generation cephalosporins in Shigella flexneri is crucial in pediatric shigellosis management. Limited studies have been conducted on molecular pattern of antibiotic resistance of S. flexneri in diarrhea endemic areas of Pakistan. The aim of the study was to analyze the antimicrobial resistance of S. flexneri isolated from pediatric diarrheal patients in Peshawar, Pakistan. A total of 199 S. flexneri isolates (clinical, n = 1 55 and non-clinical, n = 44) were investigated for drug resistance and mutational analysis of selected drug resistance genes. All isolates were found to be highly resistant to amoxicillin/clavulanic acid (88%), followed by trimethoprim-sulfamethoxazole (77%), chloramphenicol (43%), and quinolones (41.6%). About 34.5% S. flexneri isolates were found to be resistant to third-generation cephalosporin. None of the isolates was resistant to imipenem, piperacillin-tazobactam, and amikacin. Interestingly high frequency of third-generation cephalosporin resistance was observed in S. flexneri isolated from non-clinical samples (49%) when compared to clinical samples (30.5%). Furthermore, the most prevalent phenotypic-resistant patterns among third-generation cephalosporin-resistant isolates were AMC,CAZ,CPD,CFM,CRO,SXT (13%) followed by OFX,AMC,CAZ,CPD,CFM,CRO,SXT,NA,CIP (10%). The most frequently detected resistance genes were trimethoprim-sulfamethoxazole (sul2 = 84%), beta-lactamase genes (blaOXA = 87%), quinolones (qnrS = 77%), and chloramphenicol (cat = 64%). No mutation was detected in any drug-resistant genes. We are reporting for the first time the sequence of the blaTEM gene in S. flexneri. Furthermore, high third-generation cephalosporin resistance was observed in the patients who practiced self-medication as compared to those who took medication according to physician prescription. This study shows the high emergence of third-generation cephalosporin-resistant S. flexneri isolates, which is a potential threat to the community in the country. This finding will be helpful to develop a suitable antibiotic prescription regime to treat shigellosis.


Assuntos
Disenteria Bacilar , Shigella , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Resistência às Cefalosporinas/genética , Criança , Farmacorresistência Bacteriana/genética , Disenteria Bacilar/tratamento farmacológico , Disenteria Bacilar/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Paquistão/epidemiologia , Shigella flexneri
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