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1.
Plant Physiol ; 192(2): 1517-1531, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36852887

RESUMO

Meristem maintenance, achieved through the highly conserved CLAVATA-WUSCHEL (CLV-WUS) regulatory circuit, is fundamental in balancing stem cell proliferation with cellular differentiation. Disruptions to meristem homeostasis can alter meristem size, leading to enlarged organs. Cotton (Gossypium spp.), the world's most important fiber crop, shows inherent variation in fruit size, presenting opportunities to explore the networks regulating meristem homeostasis and to impact fruit size and crop value. We identified and characterized the cotton orthologs of genes functioning in the CLV-WUS circuit. Using virus-based gene manipulation in cotton, we altered the expression of each gene to perturb meristem regulation and increase fruit size. Targeted alteration of individual components of the CLV-WUS circuit modestly fasciated flowers and fruits. Unexpectedly, controlled expression of meristem regulator SELF-PRUNING (SP) increased the impacts of altered CLV-WUS expression on flower and fruit fasciation. Meristem transcriptomics showed SP and genes of the CLV-WUS circuit are expressed independently from each other, suggesting these gene products are not acting in the same path. Virus-induced silencing of GhSP facilitated the delivery of other signals to the meristem to alter organ specification. SP has a role in cotton meristem homeostasis, and changes in GhSP expression increased access of virus-derived signals to the meristem.


Assuntos
Proteínas de Arabidopsis , Meristema , Meristema/metabolismo , Proteínas de Arabidopsis/metabolismo , Flores/genética , Flores/metabolismo , Frutas/genética , Frutas/metabolismo , Homeostase , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética
2.
J Exp Bot ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39271144

RESUMO

Cotton (Gossypium hirsutum) is the world's most important fiber crop, critical to global textile industries and agricultural economies. However, cotton yield and harvest quality are undermined by the challenges introduced from invading pathogens and pests. Plant-synthesized oxylipins, specifically 9-hydroxy fatty acids resulting from 9-lipoxygenase activity (9-LOX), enhance the growth and development of many microbes and pests. We hypothesized that targeted disruption of 9-LOX-encoding genes in cotton could bolster crop resilience against prominent agronomic threats. Fusarium oxysporum f. sp. vasinfectum (FOV), Aphis gossypii (cotton aphid), and Tobacco rattle virus induced the expression of 9-oxylipin biosynthesis genes, suggesting that the 9-LOX gene products were susceptibility factors to these stressors. Transiently disrupting the expression of the 9-LOX-encoding genes by virus-induced gene silencing significantly reduced target transcript accumulation, and this correlated with impaired progression of FOV infections and a significant decrease in the fecundity of cotton aphids. These findings emphasize that the cotton 9-LOX-derived oxylipins are leveraged by multiple pathogens and pests to enhance their virulence in cotton, and reducing the expression of 9-LOX-encoding genes can benefit cotton crop vitality.

3.
Eur J Pediatr ; 183(3): 1183-1193, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38078969

RESUMO

Non-invasive cardiac imaging like echocardiogram, cardiac magnetic resonance imaging (CMR), and computed tomography angiography (CTA) play a key role in the diagnosis, aid in management and follow-up of congenital heart disease patients. Normative data for intracardiac and extracardiac vascular structures in children are currently available for echocardiogram, CMR, and non-gated CTA. We sought to establish systolic and diastolic normative data for main and branch pulmonary arteries in children using electrocardiogram (ECG)-gated CTA. Diameters and cross-sectional areas of the main and branch pulmonary arteries were measured in systole and diastole based on the aortic valve position (open versus closed) in 100 subjects who had ECG-gated cardiac CTA at our center between January 2015 through December 2020 and met our inclusion criteria. The allometric exponent (AE) for each parameter was derived, and the parameter/body surface area (BSAAE) was established using the previously described methods. A total of 100 children aged 0-18 years were analyzed; mean age was 5.3 years (SD, 6.1 years). Z-score curves were plotted in relation to the BSA for the mean, maximum, and minimum diameters and cross-sectional area of the main and branch pulmonary arteries for systole and diastole.   Conclusion: We report systolic and diastolic mean, maximum, and minimum diameters and cross-sectional areas along with Z-scores and normative curves for the main and branch pulmonary arteries in children derived using ECG-gated cardiac CTA. We believe our results can help identify abnormally sized main and branch pulmonary arteries. What is Known: • Normative data for intracardiac and extracardiac vascular structures in the pediatric population are available for echocardiography, cardiac MRI and non-ECG gated CTA. • Z-scores with standard deviations are commonly used in children, but SDs are not constant across body sizes due to heteroscedasticity. What is New: • Allometric exponent was derived for each parameter and the parameter/body surface area (BSA) was established. • This is the first ECG-gated CTA study to provide normative en face systolic, diastolic diameters and cross-sectional areas along with Z-scores and normative curves for the main and branch pulmonary arteries in children.


Assuntos
Angiografia por Tomografia Computadorizada , Artéria Pulmonar , Criança , Humanos , Pré-Escolar , Artéria Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Ecocardiografia , Eletrocardiografia
4.
Dig Dis Sci ; 68(2): 497-513, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35984611

RESUMO

BACKGROUND: Hyperfibrinolysis and coagulation dysfunction may occur in cirrhotic patients with acute variceal bleed (AVB) despite successful endotherapy. AIMS: To prospectively study the association of endogenous heparinoids and coagulation dysfunction with variceal rebleeding and outcome in cirrhosis. METHODS: Consecutive patients were assessed with conventional coagulation tests, SONOCLOT™ [(global(gb) and heparinase(h) treated] and factors VII, VIII, XIII, X, tissue plasminogen activator, and plasminogen activator inhibitor ELISA assays in a university hospital. Heparin-like-effect (HLE) was defined as ≥ 20% difference in paired gb/h-SONOCLOT™ traces for activated clotting time (ACT). RESULTS: Of 143 patients screened, 90 (46.4 ± 11.7 years, males 82.2%, ethanol-related 58.8%) were recruited, who bled from esophageal varices (81,90.0%), gastric varices (6,6.6%), or esophageal varices with portal hypertensive gastropathy (3,3.3%). Twenty (21.7%) had early rebleeding, mainly post-variceal ligation ulcer related (70%). Patients who rebled had low Factor XIII [1.6 (1.2-2.1) vs 2.4 ng/ml (2.0-2.8) P = 0.035] and Factor VII (94.1 ± 46.9 vs. 124.0 ± 50.4, P = 0.023). On receiver operating curve analysis, the gbACT > 252 s (sensitivity 86.8%, specificity 76.9%, P < 0.001), hACT > 215 s (sensitivity 71.1%, specificity 70.3%, P < 0.001), and HLE > 50% (sensitivity 69.5%, specificity 70.3%, P = 0.006) predicted rebleeding. Baseline Factor VIII (HR 1.26; 95% CI 1.17-1.34, P < 0.001), low factor VII (HR 0.89; 95% CI 0.76-0.98, P = 0.035), and lysis (HR 1.25, 95% CI 1.17-1.33, P < 0.001) predicted mortality. Endogenous heparinoids at baseline predicted sepsis (HR 1.8; 95% CI 1.4-6.5; P = 0.022), rebleeding events (HR 1.2; 95% CI 1.1-6.3; P = 0.030), and mortality (HR 1.1; 95% CI 1.0-4.6; P = 0.030). CONCLUSIONS: Hyperfibrinolysis, Factor VII/XIII deficiency, and HLE are associated with rebleeding after AVB. Trial Registration NCT04111120 available from https://clinicaltrials.gov/ct2/show/NCT04111120 .


Assuntos
Varizes Esofágicas e Gástricas , Heparinoides , Masculino , Humanos , Varizes Esofágicas e Gástricas/etiologia , Fator VII , Ativador de Plasminogênio Tecidual , Hemorragia Gastrointestinal/etiologia , Heparina , Fibrinólise , Cirrose Hepática/complicações , Ligadura/efeitos adversos
5.
Drug Chem Toxicol ; : 1-10, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36594462

RESUMO

7-Methylxanthine (7-MX, CAS No. 552-62-5, purity 99.46%) is the first orally administered drug candidate, which showed anti-myopic activity in different pre-clinical studies. In the present study, we investigated the in-vivo genotoxic and mutagenic toxicity of 7-MX in Wistar rats using comet/single-cell gel electrophoresis, chromosomal aberration and micronucleus assays after oral administration. For the single-dose study (72 h), two doses of 7-MX 300 and 2000 mg/kg body weight were selected. For a repeated dose 28 d study, three doses (250, 500, and 1000 mg/kg) of 7-MX were selected. The doses were administered via oral gavage in the suspension form. Blood and major vital organs such as bone marrow, lung and liver were used to perform comet/single cell gel electrophoresis, chromosomal aberration, and micronucleus assays. The in-vitro Ames test was performed on TA98 and TA100 strains. In the chromosomal aberration study, a non-significant increase in deformities such as stickiness, ring chromosome, and endoreduplication was observed in bone marrow cells of 7-MX treated groups. These chromosomal alterations were observed upon treatment with doses of 2000 mg/kg single dose for 72 h and 1000 mg/kg repeated dose for 28 d. At a dose of 500 mg/kg, DNA damage in terms of tail length, tail moment, % tail DNA and the olive tail moment was also found to be non-significant in 7-MX treated groups. The Ames test showed the non-mutagenic nature of 7-MX in both strains of TA98 and TA100 of Salmonella typhimurium with or without metabolic activation. Thus, the present work is interesting in view of the non- genotoxicity and non-mutagenicity of repeated doses of 7-MX.

6.
J Viral Hepat ; 29(5): 395-406, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35266624

RESUMO

Chronic hepatitis C virus (HCV) infection is associated with neuropsychiatric changes. Also, patients with cirrhosis may develop overt or minimal hepatic encephalopathy. Sustained virological response (SVR) with direct-acting antiviral agents (DAAs) may improve the neuropsychiatric manifestations and quality of life (QoL). Consecutive patients (with and without cirrhosis, all genders and aged 18-65 years) with hepatitis C were assessed at enrolment and at 12 weeks after therapy completion for mood (Beck's Depression Inventory [BDI]), anxiety (generalized anxiety disorder [GAD-7]), QoL (SF-36 ver.2) and computer-based tests for number connection (NCT), visual memory, Stroop test and reaction times. We recruited 385 viraemic chronic HCV patients (76.1% male, 21.0% cirrhotic, mean age 39.4 ± 14.2 years, 59.3% genotype 3, mean HCV RNA load 5.8 log). Overall SVR-12 rates were 90.6%, with cure rates 87.6% and 91.4% in patients with and without cirrhosis, respectively. Patients who achieved SVR-12 had mean percentage reduction in BDI (11.3%, p = .000), GAD (8.6%, p = .001) and Stroop test (58.4%, p = .001), with improved NCT (1.7%, p = .001), visual memory (13.7%, p = .001) and digit span (23.8%, p = .002). On multivariate logistic regression, adherence (OR, 17.5 [95% CI 2.80-110.50], p = .000), high ALT (OR 1.02 [95% CI 1.00-1.05]), and BDI score (OR 1.73 [95% CI 1.42-3.26] p = .039) predicted cure. SVR-12 was associated with improved visual memory ≥5.5 (AUC-0.708; sensitivity 62.5%, specificity 63%, p = .000) and % correct Stroop test responses >26.6% (AUC-0.918, sensitivity 94.4% specificity 80.4%, p = .000). In conclusion, given the cumulative evidence of the safety of DAAs and efficacy of improving cognitive and neuropsychological and quality-of-life outcomes irrespective of age and gender, as shown in our study, future recommendations should focus on integrated universal HCV care to enable HCV elimination.


Assuntos
Hepatite C Crônica , Hepatite C , Adulto , Antivirais/uso terapêutico , Ansiedade , Transtornos de Ansiedade/induzido quimicamente , Transtornos de Ansiedade/complicações , Transtornos de Ansiedade/tratamento farmacológico , Estudos de Coortes , Depressão , Feminino , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Humanos , Cirrose Hepática , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resposta Viral Sustentada , Resultado do Tratamento
7.
Biofouling ; 38(5): 455-481, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35673761

RESUMO

Enzymes, also known as biocatalysts, display vital properties like high substrate specificity, an eco-friendly nature, low energy inputs, and cost-effectiveness. Among their numerous known applications, enzymes that can target biofilms or their components are increasingly being investigated for their anti-biofouling action, particularly in healthcare, food manufacturing units and environmental applications. Enzymes can target biofilms at different levels like during the attachment of microorganisms, formation of exopolymeric substances (EPS), and their disruption thereafter. In this regard, a consortium of carbohydrases that can target heterogeneous polysaccharides present in the EPS matrix may provide an effective alternative to conventional chemical anti-biofouling methods. Further, for complete annihilation of biofilms, enzymes can be used alone or in conjunction with other antimicrobial agents. Enzymes hold the promise to replace the conventional methods with greener, more economical, and more efficient alternatives. The present article explores the potential and future perspectives of using carbohydrases as effective anti-biofilm agents.


Assuntos
Bactérias , Biofilmes , Incrustação Biológica , Glicosídeo Hidrolases , Química Verde , Anti-Infecciosos , Bactérias/enzimologia , Incrustação Biológica/prevenção & controle , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Glicosídeo Hidrolases/isolamento & purificação , Glicosídeo Hidrolases/metabolismo , Química Verde/métodos
9.
J Ultrasound Med ; 36(1): 109-120, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27925675

RESUMO

OBJECTIVES: Functional appliances are used for treatment of lower-jaw deficiencies in growing individuals; however, their effectiveness is debatable. Low-intensity pulsed ultrasound (US) is a noninvasive method, which has been shown to stimulate cartilage and bone formation with 20 minutes of application. This study was designed to test the hypothesis that increasing low-intensity pulsed US application from 20 to 40 min/d will enhance mandibular condylar growth in growing rats, especially when combined with a functional appliance. METHODS: Fifty-four Sprague Dawley rats were divided into 6 groups (n = 9): control, low-intensity pulsed US for 20 minutes, low-intensity pulsed US for 40 minutes, the functional appliance, the functional appliance plus low-intensity pulsed US for 20 minutes, and the functional appliance plus low-intensity pulsed US for 40 minutes. Low-intensity pulsed US was applied for 28 days. All rats were then euthanized, and their mandibles were dissected for morphometric, histomorphometric, and micro-computed tomographic analyses. RESULTS: Among all study groups, the 20-minute US group showed significant increases in most of the measured variables (P < .05) except for condylar process length (P = .18), whereas the functional appliance-plus-40-min US group showed the least favorable results. The 20-minute US group showed increases in proliferative and hypertrophic cell counts and widths and enhanced microarchitecture of trabecular bone compared with the 40-minute US group. The functional appliance-plus-20-minute US group showed better results compared with the functional appliance-alone and functional appliance-plus-40-minute US groups. CONCLUSIONS: A daily application of low-intensity pulsed US for 20 minutes in growing rats affects mandibular growth, either alone or in combination with a functional appliance. Further study with a longer observation period is required to study the long-term effects and stability of newly formed bone.


Assuntos
Côndilo Mandibular/diagnóstico por imagem , Aparelhos Ortodônticos Funcionais , Osteogênese/fisiologia , Ondas Ultrassônicas , Animais , Modelos Animais , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Tomografia Computadorizada por Raios X
10.
J Ultrasound Med ; 35(2): 349-58, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26782167

RESUMO

OBJECTIVES: The objectives of this systematic review with a meta-analysis were to critically analyze the available scientific literature regarding the effects of low-intensity pulsed ultrasound (US) on stimulating bone regeneration and bone maturation during distraction osteogenesis in humans and to determine whether the stimulatory effect of low-intensity pulsed US can effectively reduce the associated treatment time. METHODS: Studies were considered for inclusion if they were randomized clinical trials that examined the effect of low-intensity pulsed US on distraction osteogenesis compared to conventional distraction osteogenesis. The primary outcome was reduced treatment time. Study selection, risk of bias assessment, and data extraction were performed in duplicate. A random-effects meta-analysis model was used when more than 3 trials were eligible for a quantitative analysis and considering the expected differences in interventions and measurement tools. RESULTS: Five randomized clinical trials, with a moderate to high risk of bias, met the eligibility criteria. Four trials examining tibial distraction osteogenesis in 118 patients were combined in a meta-analysis. A statistically significant difference for reduced treatment time between distraction osteogenesis with low-intensity pulsed US and standard distraction osteogenesis was evident (mean difference, -15.236 d/cm; random-effects 95% confidence interval, -19.902 to -10.569 d/cm; P < .0001). As for the mandible, only 1 clinical trial was available, which showed no significant effect of low-intensity pulsed US therapy on distraction osteogenesis. CONCLUSIONS: Current available evidence suggests that low-intensity pulsed US therapy may provide a reduction in the overall treatment time for tibial distraction osteogenesis. However, this conclusion should be considered with caution, given the moderate to high risk of bias in the included randomized clinical trials.


Assuntos
Regeneração Óssea/efeitos da radiação , Osteogênese por Distração , Ondas Ultrassônicas , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
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