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1.
Front Microbiol ; 15: 1405090, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863756

RESUMO

Rice false smut, which is caused by the soil-borne fungal pathogen Ustilaginoidea virens (U. virens), is one of the most threatening diseases in most of the rice-growing countries including India that causes 0.5-75% yield loss, low seed germination, and a reduction in seed quality. The assessment of yield loss helps to understand the relevance of disease severity and facilitates the implementation of appropriate management strategies. This study aimed to mitigate biotic stress in rice by employing a rhizobacterial-based bioformulation, which possesses diverse capabilities as both a plant growth promoter and a biocontrol agent against U. virens. Rhizobacteria were isolated from the soil of the rice rhizospheres from the healthy plant of the false smut affected zone. Furthermore, they were identified as Bacillus strains: B. subtilis (BR_4), B. licheniformis (BU_7), B. licheniformis (BU_8), and B. vallismortis (KU_7) via sequencing. Isolates were screened for their biocontrol potential against U. virens under in vitro conditions. The antagonistic study revealed that B. vallismortis (KU_7) inhibited U. virens the most (44.6%), followed by B. subtilis BR_4 (41.4%), B. licheniformis BU_7 (39.8%), and B. licheniformis BU_8 (43.5%). Various biochemical and plant growth promoting attributes, such as phosphate and Zn solubilization, IAA, ammonium, siderophore, and chitinase production, were also investigated for all the selected isolates. Furthermore, the potential of the isolates was tested in both in vitro and field conditions by employing talc-based bioformulation through bio-priming and root treatment. The application of bioformulation revealed a 20% decrease in disease incidence in plants treated with B. vallismortis (KU_7), a 60.5% increase in the biological yield, and a 45% increase in the grain yield. This eco-friendly approach not only controlled the disease but also improved the grain quality and reduced the chaffiness.

2.
Front Pediatr ; 12: 1273590, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440184

RESUMO

Recipients of hematopoietic stem cell transplants and solid organ transplants frequently develop pulmonary infiltrates from both infectious and non-infectious etiologies. Differentiation and further characterization of microbiologic etiologies-viral, bacterial, and fungal-can be exceedingly challenging. Pediatric patients face unique challenges as confirmatory evaluations with bronchoscopy or lung biopsy may be limited. A generalizable approach to diagnosing and managing these conditions has not been well established. This paper aims to summarize our initial clinical approach while discussing the relative evidence informing our practices. A pediatric patient with characteristic infiltrates who has undergone HSCT is presented to facilitate the discussion. Generalizable approaches to similar patients are highlighted as appropriate while highlighting considerations based on clinical course and key risk factors.

3.
Org Biomol Chem ; 22(13): 2608-2619, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38450716

RESUMO

A facile and user-friendly protocol for the synthesis of trifluoroethoxy/aryloxy cinnolines, cinnolinones and indazoles from o-alkynylaniline in good-to-excellent yields has been developed using a metal-free diazotization reagent (a combination of BF3·OEt2 and TBN). The methodology has been further extended to construct bis-cinnolinones and for the chemoselective synthesis of N-propargylated cinnolinones.

4.
Hosp Pediatr ; 14(2): 84-92, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38247356

RESUMO

OBJECTIVES: This study focused on children with confirmed methicillin-resistant Staphylococcus aureus (MRSA) infections to determine MRSA screening utility in guiding empirical anti-MRSA treatment of children without history of MRSA infection. We examined the concordance of screens to assess differences by infection type and used statistical analysis to determine significant contributors to concordance. METHODS: Pediatric hospital patients admitted from 2002 through 2022 were included. Subjects had MRSA infections subsequent to MRSA surveillance screens performed the preceding year. Statistical analysis identified associations between MRSA screens and infections. Number needed to treat analysis calculated the utility of rescreening. RESULTS: Among 246 subjects, 39.0% had concordant screens; 151 (61.4%) screens were obtained in the 2 weeks preceding infection. Sensitivity for bacteremia was 50.0% (n = 42), for endotracheal/respiratory 44.4% (n = 81), and 29.4% (n = 102) for skin and soft-tissue infection. For children aged younger than 6 months, sensitivity was 35.9% (n = 78). Multivariable analysis significantly associated days since screening with decreasing likelihood of concordance. Regression modeled the probability of concordance to drop below 50.0% for all infections after 4 days, after 6 days for bacteremia specifically, and 12 days for endotracheal/respiratory infections. CONCLUSIONS: The concordance of screens was far lower than negative predictive values found previously; earlier studies were possibly impacted by low prevalence and exclusion of children at high risk to inform high negative predictive values. We suggest that negative MRSA screens should not invalidate reasonable suspicion for MRSA infection in patients with high pretest probabilities.


Assuntos
Bacteriemia , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Infecções Cutâneas Estafilocócicas , Humanos , Criança , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Hospitalização , Bacteriemia/diagnóstico , Bacteriemia/epidemiologia , Bacteriemia/tratamento farmacológico , Antibacterianos/uso terapêutico , Estudos Retrospectivos
5.
Front Oral Health ; 4: 1286780, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38024143

RESUMO

Background: There is a high incidence of oral cancer and oral potential malignant disorder observed in southeast Asian countries such as India. Our study aimed to assess the correlation between screening and histopathological diagnosis and to predict the specificity and sensitivity of chair-side/field-based assessment of the oral lesion. Materials and methods: A total of 40,852 subjects aged between 20 and 60 years were screened in the 1st phase of the study, suspected lesions were stained with toluidine blue (Manufactured by Otto Chemicals private limited, India) at two time points, those who stained positively during the two points were taken up for biopsy. Provisional diagnosis was later correlated with histopathological diagnosis. Results: Subjects who underwent biopsy had a mean age of (49.01 ± 9.8 years), Leukoplakia (1.5%) was the most common lesion observed among tobacco users, interestingly it had the least correlation (39.6%) in diagnosis, Overall sensitivity (88%) and a positive predictive value (80%) was high for clinical diagnosis of OPMD in our study. Conclusion: Correlation of clinical and histopathological diagnosis observed in our study confirms higher yield of true positives while screening in remote and vulnerable populations, which would assure a better quality of life for these subjects.

6.
Biol Methods Protoc ; 8(1): bpad021, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854896

RESUMO

Recent studies highlight the effectiveness of hybrid Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) vaccines combining wild-type nucleocapsid and Spike proteins. We have further enhanced this strategy by incorporating delta and omicron variants' spike protein mutations. Both delta and omicron mark the shifts in viral transmissibility and severity in unvaccinated and vaccinated patients. So their mutations are highly crucial for future viral variants also. Omicron is particularly adept at immune evasion by mutating spike epitopes. The rapid adaptations of Omicron and sub-variants to spike-based vaccines and simultaneous transmissibility underline the urgency for new vaccines in the continuous battle against SARS-CoV-2. Therefore, we have added three persistent T-cell-stimulating nucleocapsid peptides similar to homologous sequences from seasonal Human Coronaviruses (HuCoV) and an envelope peptide that elicits a strong T-cell immune response. These peptides are clustered in the hybrid spike's cytoplasmic region with non-immunogenic linkers, enabling systematic arrangement. AlphaFold (Artificial intelligence-based model building) analysis suggests omitting the transmembrane domain enhances these cytoplasmic epitopes' folding efficiency which can ensure persistent immunity for CD4+ structural epitopes. Further molecular dynamics simulations validate the compact conformation of the modeled structures and a flexible C-terminus region. Overall, the structures show stability and less conformational fluctuation throughout the simulation. Also, the AlphaFold predicted structural epitopes maintained their folds during simulation to ensure the specificity of CD4+ T-cell response after vaccination. Our proposed approach may provide options for incorporating diverse anti-viral T-cell peptides, similar to HuCoV, into linker regions. This versatility can be promising to address outbreaks and challenges posed by various viruses for effective management in this era of innovative vaccines.

7.
J Pediatr Pharmacol Ther ; 28(4): 316-322, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795280

RESUMO

OBJECTIVE: This study evaluated newborn gentamicin serum concentrations after birth and the effects on the newborn after extended interval gentamicin dosing in peripartum mothers. METHODS: This was a single-center, retrospective chart review of neonates born to mothers that received peripartum once-daily gentamicin dosing of approximately 5 mg/kg within 12 hours of delivery. A gentamicin serum concentration was obtained immediately after birth in the newborn. The primary outcome was initial neonatal gentamicin serum concentration after birth. Several secondary outcomes were evaluated including nephrotoxicity and ototoxicity. A subgroup analysis comparing baseline demographics of mother-newborn dyads with birth neonatal serum concentrations of less than 2 mcg/mL versus 2 mcg/mL or greater was performed. RESULTS: A total of 32 mother-newborn dyads were included. Newborns had a median gestational age of 39.4 weeks and median birth weight of 3.4 kg. The mean initial gentamicin serum concentration was elevated at 3.1 ± 1.9 mcg/mL among all newborns. The median maternal dose based on actual body weight in newborns with gentamicin serum concentrations less than 2 mcg/mL was 3.5 (IQR, 3.3-4.8) mg/kg versus 4.8 (IQR, 4.3-5.2) mg/kg in those that had serum concentrations of 2 mcg/mL or greater (p = 0.025). All newborn gentamicin serum concentrations were less than 2 mcg/mL for maternal doses given less than 1 hour prior to delivery (n = 8). There were no significant differences in nephrotoxicity or ototoxicity. CONCLUSIONS: Peripartum once daily dosing of gentamicin administered between 1 to 12 hours of birth may lead to clinically significant serum concentrations in newborns.

8.
Org Lett ; 25(18): 3254-3259, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37126068

RESUMO

The merger of two bifunctional moieties, 2-alkynylaniline and alkynylnitriles, in the presence of ZnBr2 offers the tunable synthesis of two biologically important motifs: acrylonitrile indoles and 3-cyanoquinolines. The group present on the terminal alkyne of 2-alkynylaniline regulates the reaction pathways, intra- versus intermolecular, which thereby adds stereoselectivity and regioselectivity in this protocol. The conversion of an acrylonitrile indole ring to quinoline is an intriguing synthetic utility of this methodology.

9.
World J Microbiol Biotechnol ; 39(4): 102, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36797527

RESUMO

Xylitol, a sugar substitute, is widely used in various food formulations and finds a steady global market. In this study, xylitol crystals were produced from corncob by fermentation (as an alternative to the chemical catalytic process) by a GRAS yeast Pichia caribbica MTCC 5703 and characterized in detail for their purity and presence of any possible contaminant that may adversely affect mammalian cell growth and proliferation. The acute and chronic oral toxicity trials demonstrated no gross pathological changes with average weekly weight gain in female Wistar rats at high xylitol loading (LD50 > 10,000 mg/kg body weight). The clinical chemistry analysis supported the evidence of no dose-dependent effect by analyzing blood biochemical parameters. The finding suggests the possible application of the crystals (> 98% purity) as a food-grade ingredient for commercial manufacture pending human trials.


Assuntos
Xilitol , Zea mays , Ratos , Humanos , Animais , Xilitol/toxicidade , Zea mays/química , Biomassa , Ratos Wistar , Fermentação , Xilose , Mamíferos
10.
Sci Rep ; 13(1): 795, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36646750

RESUMO

Raffinose family oligosaccharides (RFOs) are known to have important physiological functions in plants. However, the presence of RFOs in legumes causes flatulence, hence are considered antinutrients. To reduce the RFOs content to a desirable limit without compromising normal plant development and functioning, the identification of important regulatory genes associated with the biosynthetic pathway is a prerequisite. In the present study, through comparative RNA sequencing in contrasting genotypes for seed RFOs content at different seed maturity stages, differentially expressed genes (DEGs) associated with the pathway were identified. The DEGs exhibited spatio-temporal expression patterns with high RFOs variety showing early induction of RFOs biosynthetic genes and low RFOs variety showing a late expression at seed maturity. Selective and seed-specific differential expression of raffinose synthase genes (AhRS14 and AhRS6) suggested their regulatory role in RFOs accumulation in peanut seeds, thereby serving as promising targets in low RFOs peanut breeding programs. Despite stachyose being the major seed RFOs fraction, differential expression of raffinose synthase genes indicated the complex metabolic regulation of this pathway. The transcriptomic resource and the genes identified in this study could be studied further to develop low RFOs varieties, thus improving the overall nutritional quality of peanuts.


Assuntos
Arachis , Melhoramento Vegetal , Rafinose/metabolismo , Arachis/genética , Arachis/metabolismo , Oligossacarídeos/metabolismo , Sementes/metabolismo
11.
J Org Chem ; 88(1): 132-142, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36524970

RESUMO

A new methodology for the synthesis of N-haloindole-fused dihydrothiopyrano derivatives via (3 + 3)-annulation of donor-acceptor cyclopropanes (DACs) with indoline-2-thiones in the presence of Sc(OTf)3 as a Lewis acid catalyst has been developed. This protocol provides a variety of indole-fused dihydrothiopyrano molecules in good to excellent yields, which architecturally resemble other indole-fused tricyclic molecules having potential medicinal value. In addition, we have described a detailed reaction mechanism and transformation of the furnished product into N-fused thiazino indole molecule.


Assuntos
Ciclopropanos , Tionas , Estrutura Molecular , Catálise
12.
Org Biomol Chem ; 20(24): 4933-4941, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35648486

RESUMO

A chemoselective and metal/additive-free protocol for the synthesis of propargylic cyclic imine derivatives via (3 + 2)-cycloaddition of donor-acceptor cyclopropanes and alkynylnitriles in the presence of BF3·OEt2 has been established. The newly developed methodology provided access to a variety of propargylic cyclic imines in good to excellent yields. In addition, the synthesis of propargylic amines and the corresponding very stable enol derivatives from the title compound is also explored.


Assuntos
Iminas , Ciclização , Reação de Cicloadição , Estrutura Molecular , Estereoisomerismo
13.
Bioresour Technol ; 350: 126916, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35231597

RESUMO

Lignocellulosic biomass is projected as a prospective renewable alternative to petroleum for the production of fuel and chemicals. Pretreatment is necessary to disrupt the lignocellulosic structure for extraction of cellulose. Biomass after pretreatment is segregated into cellulose rich solid fraction and black liquor (lignin and hemicelluloses) as a liquid stream. The plant polysaccharide-based industry primarily utilizes the cellulosic fraction as raw material, and carbon rich black liquor discarded as waste or burnt for energy recovery. This review highlights the recent advancements in the biological and chemical valorization of black liquor into fuels and chemicals. The recent research attempted for bioconversion of black liquor into Bioplastic, Biohydrogen, Biogas, and chemicals has been discussed. In addition, the efforts to replace the conventional energy recovery method with the advanced chemical process along with their modifications have been reviewed that will decide the sustainability of the lignocellulosic biomass-based industry.


Assuntos
Biocombustíveis , Lignina , Biomassa , Celulose , Lignina/química , Estudos Prospectivos
14.
Chemosphere ; 295: 133893, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35134407

RESUMO

Sugarcane bagasse is an abundantly available agricultural waste having high potential that is still underutilized and mostly burnt as fuel. There are various processes available for bagasse utilization in improved ways and one such process is anaerobic digestion (AD) of bagasse for biogas production. The complex structure of biomass is recalcitrant to degradation and is a major hindrance for the anaerobic digestion, so different pretreatment methods are applied to deconstruct the bagasse for microbial digestion. In this review, different processes developed for the pretreatment of bagasse and their effect on biogas production have been extensively covered. Moreover, combination of pretreatment methods, co-digestion of bagasse with other waste (nitrogen rich or easily digestible) for enhanced biogas production and biomethane generation along with other value-added products has also been reviewed. The digestate contains a significant amount of organics with partial recovery of energy and products and is generated in huge amount that further creates disposal problem. Therefore, integration of digestate valorization with AD through gasification, pyrolysis, hydrothermal carbonization and use of microalgae for maximum recovery of energy and value-added products have also been evaluated. Thus, this review highlights major emerging area of research for improvement in bagasse based processes for enhanced biogas production along with digestate valorization to make the overall process economical and sustainable.


Assuntos
Biocombustíveis , Saccharum , Anaerobiose , Celulose/metabolismo , Metano/metabolismo , Saccharum/metabolismo
16.
J Pediatr Hematol Oncol ; 44(2): e334-e342, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34224520

RESUMO

BACKGROUND: Invasive fungal diseases (IFDs) are opportunistic infections that result in significant morbidity and mortality in pediatric oncology patients. Predictive risk tools for IFD in pediatric cancer are not available. METHODS: We conducted a 7-year retrospective study of pediatric oncology patients with a diagnosis of febrile neutropenia at UCM Comer Children's Hospitals. Fourteen clinical, laboratory, and treatment-related risk factors for IFD were analyzed. Stepwise variable selection for multiple logistic regression was used to develop a risk prediction model for IFD. Two comparative analyses have been conducted: (i) all suspected IFD cases and (ii) all proven and probable IFD cases. RESULTS: A total of 667 febrile neutropenia episodes were identified in 265 patients. IFD was diagnosed in 62 episodes: 13 proven, 27 probable, and 22 possible. In the final multiple logistic regression models, 5 variables were independently significant for both analyses: fever days, neutropenia days, hypotension, and absolute lymphocyte count <250 at the time of diagnosis. The odds ratio and a relative weight for each factor were then calculated and summed to calculate a predictive score. A risk score of ≤4 and ≤5 (10/11 maximum) for each model signifies low risk, respectively (<1.2% incidence). Model discrimination was evaluated by the area under the receiver operator characteristics curve with an area under the curve of 0.95/0.94 for each model. CONCLUSION: Our prediction IFD risk models perform well, are easy-to-use, and are based on readily available clinical data. Profound lymphopenia absolute lymphocyte count <250 mm3 could serve as a new important prognostic marker for the development of IFD in pediatric cancer and hematopoietic stem cell transplant patients.


Assuntos
Neutropenia Febril , Transplante de Células-Tronco Hematopoéticas , Neoplasias , Antifúngicos/uso terapêutico , Criança , Neutropenia Febril/tratamento farmacológico , Neutropenia Febril/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Estudos Retrospectivos , Fatores de Risco
17.
Res Sq ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34845442

RESUMO

The mechanisms explaining progression to severe COVID-19 remain poorly understood. It has been proposed that immune system dysregulation/over-stimulation may be implicated, but it is not clear how such processes would lead to respiratory failure. We performed comprehensive multiparameter immune monitoring in a tightly controlled cohort of 128 COVID-19 patients, and used the ratio of oxygen saturation to fraction of inspired oxygen (SpO2 / FiO2) as a physiologic measure of disease severity. Machine learning algorithms integrating 139 parameters identified IL-6 and CCL2 as two factors predictive of severe disease, consistent with the therapeutic benefit observed with anti-IL6-R antibody treatment. However, transcripts encoding these cytokines were not detected among circulating immune cells. Rather, in situ analysis of lung specimens using RNAscope and immunofluorescent staining revealed that elevated IL-6 and CCL2 were dominantly produced by infected lung type II pneumocytes. Severe disease was not associated with higher viral load, deficient antibody responses, or dysfunctional T cell responses. These results refine our understanding of severe COVID-19 pathophysiology, indicating that aberrant cytokine production by infected lung epithelial cells is a major driver of immunopathology. We propose that these factors cause local immune regulation towards the benefit of the virus.

18.
Bioresour Technol ; 330: 124981, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33756182

RESUMO

Syringyl monomeric units are the most common intermediates encountered during hardwood lignin degradation. In the present study, efficient utilization of syringaldehyde (SAld), syringic acid (SAc) by Burkholderia sp. ISTR5 (R5) has been shown. The proteogenomic analysis of Burkholderia sp. ISTR5 was done to understand the enzymes involved in the degradation of syringaldehyde and syringic acid. Various proteins such as aldehyde dehydrogenase, laccase, and oxidoreductases were highly upregulated during growth on syringaldehyde and syringic acid. R5 completely transformed both the substrates SAld and SAc to other hydrocarbons in 48 h and 24 h, respectively. Moreover, bioconversion of syringyl lignins followed an unusual pathway and accumulated a considerable amount of industrially valuable chemical malic acid in the reaction titer. This study shows the robust chassis of R5 to cope with the aromatic aldehydic stress and simultaneous bioconversion into valuable products for an efficient biorefinery.


Assuntos
Burkholderia , Lignina , Malatos , Oxirredutases
19.
Hosp Pediatr ; 11(4): 327-333, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33731336

RESUMO

OBJECTIVES: Hospitalized children experience frequent nighttime awakenings. Oral medications are commonly administered around the clock despite the comparable efficacy of daytime administration schedules, which promote sleep. With this study, we evaluated the effectiveness of a quality improvement initiative to increase the proportion of sleep-friendly antibiotic administration schedules. METHODS: Interprofessional stakeholders modified computerized provider order entry defaults for 4 oral antibiotic medications, from around the clock to administration occurring exclusively during waking hours. Additionally, care-team members received targeted education. Outcome measures included the proportion of sleep-friendly administration schedules and patient caregiver-reported disruptions to sleep. Pre- and posteducation surveys were used to evaluate education effectiveness. Balancing measures were missed antibiotic doses and related escalations of care. RESULTS: Interrupted time series analysis revealed a 72% increase (interceptpre: 18%; interceptpost: 90%; 95% confidence interval: 65%-79%; P < .001) in intercept for percentage of orders with sleep-friendly administration schedules (orders: n pre = 1014 and n post = 649). Compared with preeducation surveys, care-team members posteducation were more likely to agree that oral medications scheduled around the clock cause sleep disruption (resident: 71% pre, 90% post [P = .01]; nurse: 63% pre, 79% post [P = .03]). Although sleep-friendly orders increased, patient caregivers reported an increase in sleep disruption due to medications (pre 28%, post 46%; P < .001). CONCLUSIONS: A simple, low-cost intervention of computerized provider order entry default modifications and education can increase the proportion of sleep-friendly oral antibiotic administration schedules for hospitalized children. Patient perception of sleep is impacted by multiple factors and often does not align with objective data. An increased focus on improving sleep during hospitalization may result in heightened awareness of disruptions.


Assuntos
Pacientes Internados , Melhoria de Qualidade , Cuidadores , Criança , Criança Hospitalizada , Humanos , Sono
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