RESUMO
Antibiotic activity is limited by the physical construction of the Gram-negative cell envelope. Species of the Burkholderia cepacia complex (Bcc) are known as intrinsically multidrug-resistant opportunistic pathogens with low permeability cell envelopes. Here, we re-examined a previously performed chemical-genetic screen of barcoded transposon mutants in B. cenocepacia K56-2, focusing on cell envelope structural and functional processes. We identified structures mechanistically important for resistance to singular and multiple antibiotic classes. For example, susceptibility to novobiocin, avibactam, and the LpxC inhibitor, PF-04753299, was linked to the BpeAB-OprB efflux pump, suggesting these drugs are substrates for this pump in B. cenocepacia. Defects in peptidoglycan precursor synthesis specifically increased susceptibility to cycloserine and revealed a new putative amino acid racemase, while defects in divisome accessory proteins increased susceptibility to multiple ß-lactams. Additionally, disruption of the periplasmic disulfide bond formation system caused pleiotropic defects on outer membrane integrity and ß-lactamase activity. Our findings highlight the layering of resistance mechanisms in the structure and function of the cell envelope. Consequently, we point out processes that can be targeted for developing antibiotic potentiators.IMPORTANCEThe Gram-negative cell envelope is a double-layered physical barrier that protects cells from extracellular stressors, such as antibiotics. The Burkholderia cell envelope is known to contain additional modifications that reduce permeability. We investigated Burkholderia cell envelope factors contributing to antibiotic resistance from a genome-wide view by re-examining data from a transposon mutant library exposed to an antibiotic panel. We identified susceptible phenotypes for defects in structures and functions in the outer membrane, periplasm, and cytoplasm. Overall, we show that resistance linked to the cell envelope is multifaceted and provides new targets for the development of antibiotic potentiators.
Assuntos
Burkholderia cenocepacia , Complexo Burkholderia cepacia , Burkholderia , Burkholderia cenocepacia/genética , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Complexo Burkholderia cepacia/genética , Burkholderia/metabolismoRESUMO
Genome editing in non-model bacteria is important to understand gene-to-function links that may differ from those of model microorganisms. Although species of the Burkholderia cepacia complex (Bcc) have great biotechnological capacities, the limited genetic tools available to understand and mitigate their pathogenic potential hamper their utilization in industrial applications. To broaden the genetic tools available for Bcc species, we developed RhaCAST, a targeted DNA insertion platform based on a CRISPR-associated transposase driven by a rhamnose-inducible promoter. We demonstrated the utility of the system for targeted insertional mutagenesis in the Bcc strains B. cenocepacia K56-2 and Burkholderia multivorans ATCC17616. We showed that the RhaCAST system can be used for loss- and gain-of-function applications. Importantly, the selection marker could be excised and reused to allow iterative genetic manipulation. The RhaCAST system is faster, easier, and more adaptable than previous insertional mutagenesis tools available for Bcc species and may be used to disrupt pathogenicity elements and insert relevant genetic modules, enabling Bcc biotechnological applications. IMPORTANCE: Species of the Burkholderia cepacia complex (Bcc) have great biotechnological potential but are also opportunistic pathogens. Genetic manipulation of Bcc species is necessary to understand gene-to-function links. However, limited genetic tools are available to manipulate Bcc, hindering our understanding of their pathogenic traits and their potential in biotechnological applications. We developed a genetic tool based on CRISPR-associated transposase to increase the genetic tools available for Bcc species. The genetic tool we developed in this study can be used for loss and gain of function in Bcc species. The significance of our work is in expanding currently available tools to manipulate Bcc.
Assuntos
Complexo Burkholderia cepacia , Sistemas CRISPR-Cas , Elementos de DNA Transponíveis , Edição de Genes , Mutagênese Insercional , Complexo Burkholderia cepacia/genética , Edição de Genes/métodos , Elementos de DNA Transponíveis/genética , Genoma BacterianoRESUMO
BACKGROUND: Multicenter early diuretic response (DR) analysis of single furosemide dosing following neonatal cardiac surgery is lacking to inform whether early DR predicts adverse clinical outcomes. METHODS: We performed a retrospective cohort study utilizing data from the NEPHRON registry. Random forest machine learning generated receiver operating characteristic-area under the curve (ROC-AUC) and odds ratios for mechanical ventilation (MV) and respiratory support (RS). Prolonged MV and RS were defined using ≥ 90th percentile of observed/expected ratios. Secondary outcomes were prolonged CICU and hospital length of stay (LOS) and kidney failure (stage III acute kidney injury (AKI), peritoneal dialysis, and/or continuous kidney replacement therapy on postoperative day three) assessed using covariate-adjusted ROC-AUC curves. RESULTS: A total of 782 children were included. Cumulative urine output (UOP) metrics were lower in prolonged MV and RS patients, but DR poorly predicted prolonged MV (highest AUC 0.611, OR 0.98, sensitivity 0.67, specificity 0.53, p = 0.006, 95% OR CI 0.96-0.99 for cumulative 6-h UOP) and RS (highest AUC 0.674, OR 0.94, sensitivity 0.75, specificity 0.54, p < 0.001, 95% CI 0.91-0.97 UOP between 3 and 6 h). Secondary outcome results were similar. DR had fair discrimination for kidney failure (AUC 0.703, OR 0.94, sensitivity 0.63, specificity 0.71, 95% OR CI 0.91-0.98, p < 0.001, cumulative 6-h UOP). CONCLUSIONS: Early DR poorly discriminated patients with prolonged MV, RS, and LOS in this cohort, though it may identify severe postoperative AKI phenotype. Future work is warranted to determine if early DR or late postoperative DR later, in combination with other AKI metrics, may identify a higher-risk phenotype.
Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Diuréticos , Furosemida , Humanos , Estudos Retrospectivos , Masculino , Feminino , Recém-Nascido , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Diuréticos/administração & dosagem , Diuréticos/uso terapêutico , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/diagnóstico , Furosemida/administração & dosagem , Tempo de Internação/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Respiração Artificial/estatística & dados numéricos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Lactente , Curva ROC , Resultado do TratamentoRESUMO
Extreme weather events in South and Southeast Asia exert profound psychosocial impacts, amplifying the prevalence of mental illness. Despite their substantial consequences, there is a dearth of research and representation in the current literature. We conducted a systematic review of observational studies published between January 1, 2000, and January 20, 2024, to examine the impact of extreme weather events on the mental health of the South and Southeast Asian population. Quality assessment of the included studies was conducted using the Newcastle-Ottawa Scale (NOS) quality appraisal checklist. The search retrieved 70 studies that met the inclusion criteria and were included in our review. Most were from India (n = 22), and most used a cross-sectional study design (n = 55). Poor mental health outcomes were associated with six types of extreme weather events: floods, storm surges, typhoons, cyclones, extreme heat, and riverbank erosion. Most studies (n = 41) reported short-term outcome measurements. Findings included outcomes with predictable symptomatology, including post-traumatic stress disorder, depression, anxiety, general psychological distress, emotional distress and suicide. Limited studies on long-term effects showed higher mental disorders after floods and typhoons, while cyclone-exposed individuals had more short-term distress. Notably, the review identified over 50 risk factors influencing mental health outcomes, categorized into six classes: demographic, economic, health, disaster exposure, psychological, and community factors. However, the quantitative evidence linking extreme weather events to mental health was limited due to a lack of longitudinal data, lack of control groups, and the absence of objective exposure measurements. The review found some compelling evidence linking extreme weather events to adverse mental health in the South and Southeast Asia region. Future research should focus on longitudinal study design to identify the specific stressors and climatic factors influencing the relationship between climate extremes and mental health in this region.
Assuntos
Clima Extremo , Saúde Mental , Humanos , Saúde Mental/estatística & dados numéricos , Sudeste Asiático/epidemiologia , Transtornos Mentais/epidemiologia , Estudos Observacionais como AssuntoRESUMO
Brain tumors pose a significant medical challenge necessitating precise detection and diagnosis, especially in Magnetic resonance imaging(MRI). Current methodologies reliant on traditional image processing and conventional machine learning encounter hurdles in accurately discerning tumor regions within intricate MRI scans, often susceptible to noise and varying image quality. The advent of artificial intelligence (AI) has revolutionized various aspects of healthcare, providing innovative solutions for diagnostics and treatment strategies. This paper introduces a novel AI-driven methodology for brain tumor detection from MRI images, leveraging the EfficientNetB2 deep learning architecture. Our approach incorporates advanced image preprocessing techniques, including image cropping, equalization, and the application of homomorphic filters, to enhance the quality of MRI data for more accurate tumor detection. The proposed model exhibits substantial performance enhancement by demonstrating validation accuracies of 99.83%, 99.75%, and 99.2% on BD-BrainTumor, Brain-tumor-detection, and Brain-MRI-images-for-brain-tumor-detection datasets respectively, this research holds promise for refined clinical diagnostics and patient care, fostering more accurate and reliable brain tumor identification from MRI images. All data is available on Github: https://github.com/muskan258/Brain-Tumor-Detection-from-MRI-Images-Utilizing-EfficientNetB2 ).
Assuntos
Neoplasias Encefálicas , Aprendizado Profundo , Imageamento por Ressonância Magnética , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Inteligência ArtificialRESUMO
BACKGROUND: The use of peritoneal catheters for prophylactic dialysis or drainage to prevent fluid overload after neonatal cardiac surgery is common in some centres; however, the multi-centre variability and details of peritoneal catheter use are not well described. METHODS: Twenty-two-centre NEonatal and Pediatric Heart Renal Outcomes Network (NEPHRON) study to describe multi-centre peritoneal catheter use after STAT category 3-5 neonatal cardiac surgery using cardiopulmonary bypass. Patient characteristics and acute kidney injury/fluid outcomes for six post-operative days are described among three cohorts: peritoneal catheter with dialysis, peritoneal catheter with passive drainage, and no peritoneal catheter. RESULTS: Of 1490 neonates, 471 (32%) had an intraoperative peritoneal catheter placed; 177 (12%) received prophylactic dialysis and 294 (20%) received passive drainage. Sixteen (73%) centres used peritoneal catheter at some frequency, including six centres in >50% of neonates. Four centres utilised prophylactic peritoneal dialysis. Time to post-operative dialysis initiation was 3 hours [1, 5] with the duration of 56 hours [37, 90]; passive drainage cohort drained for 92 hours [64, 163]. Peritoneal catheter were more common among patients receiving pre-operative mechanical ventilation, single ventricle physiology, and higher complexity surgery. There was no association with adverse events. Serum creatinine and daily fluid balance were not clinically different on any post-operative day. Mortality was similar. CONCLUSIONS: In neonates undergoing complex cardiac surgery, peritoneal catheter use is not rare, with substantial variability among centres. Peritoneal catheters are used more commonly with higher surgical complexity. Adverse event rates, including mortality, are not different with peritoneal catheter use. Fluid overload and creatinine-based acute kidney injury rates are not different in peritoneal catheter cohorts.
Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Desequilíbrio Hidroeletrolítico , Recém-Nascido , Humanos , Criança , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Desequilíbrio Hidroeletrolítico/etiologia , Desequilíbrio Hidroeletrolítico/prevenção & controle , Equilíbrio Hidroeletrolítico , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Cateteres de Demora/efeitos adversos , Estudos RetrospectivosRESUMO
In this study, we present a comprehensive investigation of 2-amino-4,6-diphenylnicotinonitriles (APNs, 1-6), including their synthesis, cytotoxicity against breast cancer cell lines, and photophysical properties. Compound 3 demonstrates exceptional cytotoxicity, surpassing the potency of Doxorubicin. The fluorescence spectra of the synthesized 1-6 in different solvents reveal solvent-dependent shifts in the emission maximum values, highlighting the influence of the solvent environment on their fluorescence properties. A quantum chemical TD-DFT analysis provides insights into the electronic structure and fluorescence behavior of 1-6, elucidating HOMO-LUMO energy gaps, electronegativity values, and dipole moments, contributing to a deeper understanding of their electronic properties and potential reactivity. These findings provide valuable knowledge for the development of APNs (1-6) as fluorescent sensors and potential anticancer agents.
Assuntos
Antineoplásicos , Nitrilas , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Nitrilas/química , Nitrilas/síntese química , Nitrilas/farmacologia , Linhagem Celular Tumoral , Teoria Quântica , Estrutura Molecular , Espectrometria de Fluorescência , Células MCF-7 , Sobrevivência Celular/efeitos dos fármacosRESUMO
Ulcerative colitis (UC) is a chronic colonic inflammation with a significant health hazard. Aspergillus awamori (A. awamori) is a microorganism with various bioactive compounds with natural antioxidant and anti-inflammatory properties. The present work aimed to elucidate the protective and therapeutic effects of varying concentrations of A. awamori against acetic acid (AA)-induced ulcerative colitis (UC) in rats. Nine groups of albino male rats were established: a control negative group (G1), a control positive group (G2,AA), and preventive protocol groups (including G3A, G4A, and G5A) that received 100 mg, 50 mg, and 25 mg/kg b.w, respectively, of A. awamori orally and daily from the 1st day of the experiment and for 7 consecutive days. Then, they were subjected to one dose of AA intrarectally on day 8th. G3B, G4B, and G5B were termed as curative protocol groups that received one dose of AA on day 8th and then administered 100 mg, 50 mg, and 25 mg/kg b.w. of A. awamori, respectively, on day 9th and continued receiving these doses daily until day 16th. Rats in the AA group exhibited marked histopathological alterations of the distal colon, with an exaggeration of the DAI. In addition, a remarkable increase in oxidative stress was represented by the elevation of MDA and NO levels with a decline in SOD and GPx activities. In addition, upregulation of TNF-α, IL-6, and IL-1ß mRNA expressions and downregulation of Muc2 and Nrf2 levels were detected. Unambiguously, a remarkable anti-inflammatory effect was noticed either in A. awamori prevented or treated groups expounded by reducing and regulating TNF-α, IL-6, and IL-1ß with improved pathological lesion scoring. The Muc2, Nrf2, and bcl-2 gene levels were upregulated and restored also. In summary, the findings in this work reveal that A. awamori supplementation successfully alleviated the UC induced by AA, which had a better effect when administered before colitis induction.
Assuntos
Ácido Acético , Anti-Inflamatórios , Antioxidantes , Apoptose , Aspergillus , Colite Ulcerativa , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Masculino , Ratos , Antioxidantes/farmacologia , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Colo/efeitos dos fármacos , Colo/patologia , Colo/metabolismoRESUMO
Grass embryos possess structures that do not occur in any other flowering plants. Due to the specific embryo structure and position, grass embryo surfaces may be exposed to surrounding air under partial caryopsis-soil contact conditions, but whether caryopses of the grass family (Poaceae) can sense soil air humidity to initiate successful germination under partial caryopsis-soil contact conditions remain unknown. Here, we found that grass embryos have the unique ability to absorb water from atmospheric water vapor under partial caryopsis-soil contact conditions. To absorb atmospheric moisture, grass embryos developed profuse and highly elongated hairs on the embryo surface. These hairs, classically known as coleorhiza hairs, developed only on the embryo surface exposed to humid air, and submergence of the embryo surface inhibited their development. In addition to humid air-dependent development, almost all other developmental features of coleorhiza hairs were substantially different from root hairs. However, coleorhiza hair development was regulated by ROOTHAIRLESS 1. Besides the genetic control of coleorhiza hair development, we also identified how caryopses manage to keep the hairs turgid in natural open environments as the hairs were highly sensitive to dry air exposure. Moreover, we video-documented the regulation of developmental processes. The unique humid air-dependent coleorhiza hair development and their ability to absorb water from water vapor present in microsites or soil air give grasses advantages in germination and seedling establishment. Ultimately, coleorhiza hairs may have contributed to the ecological success of the grass family.
Assuntos
Germinação , Poaceae , Poaceae/fisiologia , Plântula , Solo , VaporRESUMO
OBJECTIVE: To evaluate patient-reported care utilization and outcomes among young adults with juvenile idiopathic arthritis (JIA), including factors associated with complete transfer to adult rheumatology. METHODS: We included young adults with JIA enrolled in the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry from 2015 to 2019 with age ≥ 18 years at their last clinical site visit. We used data from the CARRA Registry Long-term Follow-up program, which follows inactive CARRA Registry patients and collects patient-reported information through phone surveys. We compared the characteristics of respondents with complete and incomplete transfer to adult rheumatology care at their first Long-term Follow-up phone survey. RESULTS: We identified 540 young adults with JIA; 187 (35%) responded to the Long-term Follow-up phone survey. The 54% of respondents with complete transfer to adult rheumatology were slightly older and reported more self-assessed disease activity, morning stiffness, and pain compared to those with incomplete transfer. Biologic use was high at both timepoints and did not differ by transfer status. Patients who completed the transfer were more likely to have private insurance and be actively pursuing postsecondary education compared to those with an incomplete transfer. Across the cohort, 65% reported problems with pain or discomfort and 45% with anxiety or depression. CONCLUSION: Young adult respondents with JIA in the CARRA Registry commonly report persistent medication use, but still report more problems with pain as compared to population norms. Additional work is needed to understand how best to address comorbid pain around the period of transition to adult care.
Assuntos
Artrite Juvenil , Reumatologia , Humanos , Criança , Adulto Jovem , Adolescente , Artrite Juvenil/tratamento farmacológico , Medidas de Resultados Relatados pelo Paciente , Sistema de Registros , DorRESUMO
BACKGROUND: An evidence gap exists regarding the role of endotracheal secretions in pediatric extubation decisions. This study aims to evaluate whether endotracheal secretion burden independently correlates with pediatric extubation failure. METHODS: This is a single-center, prospective cohort study of children aged <19 years requiring intubation. Nurses (RN) and respiratory therapists (RT) independently used a novel secretion assessment score focusing on secretion volume, character, and trend. We hypothesized that the RN and RT secretion scores would not correlate with extubation outcome and inter-rater reliability would be poor. RESULTS: RN secretion character sub-score (OR 3.3, 95% CI 1.1-11.1, p = 0.048) was independently associated with extubation failure. RN and RT inter-rater reliability was poor (correlation 0.385, 95% CI 0.339-0.429, p < 0.001). A failure prediction model incorporating the RN secretion character sub-score as well as indication for mechanical ventilation and spontaneous breathing trial result demonstrated an area under the receiver operating curve of 0.817 (95% CI 0.730-0.904, p < 0.001). CONCLUSIONS: In the general pediatric population, the RN assessment of endotracheal secretion character was independently associated with extubation failure. A model incorporating indication for mechanical ventilation, spontaneous breathing result, and RN assessment of endotracheal secretion character demonstrated reasonable accuracy in predicting failure in those clinically selected for extubation. IMPACT: Development of comprehensive and sensitive extubation readiness bundles are key to balancing the competing risks of prolonged invasive mechanical ventilation duration and extubation failure. Evidence for clinical factors linked to extubation outcomes in children are limited. Endotracheal secretion burden is a common factor considered but has not been studied. This study supports a role for endotracheal secretion burden, as assessed by the bedside nurse, in extubation readiness bundles. Inter-rater reliability with respiratory therapists was poor. A model incorporating other key factors showed good discrimination for extubation outcome and sets the stage for prospective evaluation in the general population and diagnosis-specific subgroups.
Assuntos
Extubação , Respiração Artificial , Humanos , Criança , Estudos Prospectivos , Reprodutibilidade dos Testes , PulmãoRESUMO
BACKGROUND: The current study evaluated the hypothesis that the COVID-19 pandemic is associated with higher stillbirth but lower neonatal mortality rates. METHODS: We compared three epochs: baseline (2016-2019, January-December, weeks 1-52, and 2020, January-February, weeks 1-8), initial pandemic (2020, March-December, weeks 9-52, and 2021, January-June, weeks 1-26), and delta pandemic (2021, July-September, weeks 27-39) periods, using Alabama Department of Public Health database including deliveries with stillbirths ≥20 weeks or live births ≥22 weeks gestation. The primary outcomes were stillbirth and neonatal mortality rates. RESULTS: A total of 325,036 deliveries were included (236,481 from baseline, 74,076 from initial pandemic, and 14,479 from delta pandemic period). The neonatal mortality rate was lower in the pandemic periods (4.4 to 3.5 and 3.6/1000 live births, in the baseline, initial, and delta pandemic periods, respectively, p < 0.01), but the stillbirth rate did not differ (9 to 8.5 and 8.6/1000 births, p = 0.41). On interrupted time-series analyses, there were no significant changes in either stillbirth (p = 0.11 for baseline vs. initial pandemic period, and p = 0.67 for baseline vs. delta pandemic period) or neonatal mortality rates (p = 0.28 and 0.89, respectively). CONCLUSIONS: The COVID-19 pandemic periods were not associated with a significant change in stillbirth and neonatal mortality rates compared to the baseline period. IMPACT: The COVID-19 pandemic could have resulted in changes in fetal and neonatal outcomes. However, only a few population-based studies have compared the risk of fetal and neonatal mortality in the pandemic period to the baseline period. This population-based study identifies the changes in fetal and neonatal outcomes during the initial and delta COVID-19 pandemic period as compared to the baseline period. The current study shows that stillbirth and neonatal mortality rates were not significantly different in the initial and delta COVID-19 pandemic periods as compared to the baseline period.
Assuntos
COVID-19 , Natimorto , Recém-Nascido , Gravidez , Feminino , Humanos , Natimorto/epidemiologia , Pandemias , Alabama/epidemiologia , Mortalidade InfantilRESUMO
Screening for novel antibacterial compounds in small molecule libraries has a low success rate. We applied machine learning (ML)-based virtual screening for antibacterial activity and evaluated its predictive power by experimental validation. We first binarized 29,537 compounds according to their growth inhibitory activity (hit rate 0.87%) against the antibiotic-resistant bacterium Burkholderia cenocepacia and described their molecular features with a directed-message passing neural network (D-MPNN). Then, we used the data to train an ML model that achieved a receiver operating characteristic (ROC) score of 0.823 on the test set. Finally, we predicted antibacterial activity in virtual libraries corresponding to 1,614 compounds from the Food and Drug Administration (FDA)-approved list and 224,205 natural products. Hit rates of 26% and 12%, respectively, were obtained when we tested the top-ranked predicted compounds for growth inhibitory activity against B. cenocepacia, which represents at least a 14-fold increase from the previous hit rate. In addition, more than 51% of the predicted antibacterial natural compounds inhibited ESKAPE pathogens showing that predictions expand beyond the organism-specific dataset to a broad range of bacteria. Overall, the developed ML approach can be used for compound prioritization before screening, increasing the typical hit rate of drug discovery.
Assuntos
Descoberta de Drogas , Bibliotecas de Moléculas Pequenas , Estados Unidos , Bibliotecas de Moléculas Pequenas/farmacologia , Aprendizado de Máquina , Antibacterianos/farmacologiaRESUMO
BACKGROUND AND AIM: The purpose of the current study is to isolate a heavily amylase-producing bacteria of the genus Bacillus from soil samples, optimize the production of the enzyme, purify it, and evaluate its activity against biofilm-producing bacteria. A total of 12 soil samples were collected and screened for promising Bacillus species with good amylolytic activity. Isolation was done by serial dilution and plating technique and amylolytic activity was determined by starch agar plate method. Among the 12 Bacillus isolates recovered from soil samples, 7 showed positive α-amylase production. The best isolate that recorded the greatest amylolytic activity was selected for further studies. This isolate was identified by 16S rRNA sequencing as Bacillus cereus and registered under gene bank accession number OP811897. Furthermore, the α-amylase enzyme was produced by a submerged fermentation technique using best production media and partially purified by ammonium sulfate and chilled ethanol and molecular weight had been determined by SDS-PAGE gel electrophoresis. The production of α-amylase was optimized experimentally by one-factor at a time protocol and statistically by Plackett-Burman design as well as RSM CCD design. Data obtained from OFAT and CCD revealed that α-amylase activities were 1.5- and twofold respectively higher as compared to un-optimized conditions. The most significant factors had been identified and optimized by CCD design. RESULTS: Among the eleven independent variables tested by PBD, glucose, peptone, (NH4)2SO4, and Mg SO4 were the most significant parameters for α-amylase production with an actual yield of 250U/ml. The best physical parameters affecting the enzyme production were incubation time at 35 °C, and pH 5.5 for 48 h. The partially purified enzyme with 60% ammonium sulphate saturation with 1.38- fold purification showed good stability characteristics at a storage temperature of 4 °C and pH up to 8.5 for 21 days. Antibiofilm activity of purified α-amylase was determined against Pseudomonas aeruginosa (ATCC 35659) by spectrophotometric analysis and CLSM microscopic analysis. Results demonstrated biofilm inhibition by 84% of the formed Pseudomonas biofilm using a microtiter plate assay and thickness inhibition activity by 83% with live/Dead cells percentage of 17%/83% using CLSM protocol. CONCLUSIONS: A highly stable purified α-amylase from B. cereus showed promising antibiofilm activity against one of the clinically important biofilm-forming MDR organisms that could be used as a cost-effective tool in pharmaceutical industries.
Assuntos
Bacillus , alfa-Amilases , alfa-Amilases/química , Bacillus cereus , Pseudomonas aeruginosa , RNA Ribossômico 16S/genética , Concentração de Íons de Hidrogênio , Temperatura , Biofilmes , SoloRESUMO
OBJECTIVES: Early sexual initiation (ESI), defined as sexual activity that begins before 15 or 18 years of age, is one of the risky sexual behaviours that has been linked to increased likelihood of adverse consequences, such as sexually transmitted diseases, unintended pregnancies and unsafe abortions. However, to date, there are no studies investigating the prevalence and factors influencing ESI among adolescent females (aged 10-19 years) in Bangladesh. Thus, this study aimed to identify the potential determinants of ESI among adolescent females in Bangladesh based on data that are representative of the country. STUDY DESIGN: This was a cross-sectional study. METHODS: Based on the availability of the data, the analysis included a weighted sample of 2051 adolescent females aged 15-19 years from the Bangladesh Demographic and Health Survey 2017/18. Initial selection of predictor variables was based on the bivariate analysis using the Chi-squared test. Univariate and multivariable logistic regression modelling were performed to measure the crude and adjusted effect of the selected predictor variables on ESI using the odds ratio (OR). The elasticity of the effects was calculated by their 95% confidence intervals (CIs). RESULTS: Approximately 22% and 85% of female adolescents experienced ESI before the age of 15 and 18 years, respectively. Findings revealed that illiteracy (adjusted OR [AOR]: 3.61, 95% CI: 1.82-7.18), primary education (AOR: 2.08, 95% CI: 1.60-2.69), working status (AOR: 1.25, 95% CI: 0.98-1.60), living in Chittagong (AOR: 0.46, 95% CI: 0.27-0.79), living in Sylhet (AOR: 0.21, 95% CI: 0.08-0.56), reading newspapers (AOR: 0.63, 95% CI: 0.40-1.01), earlier marriage preference (AOR: 3.30, 95% CI: 2.31-4.71) and later marriage preference (AOR: 4.10, 95% CI: 3.01-5.59) were significantly linked with ESI before the age of 15 years. ESI before the age of 18 years was significantly association with primary education (AOR: 1.47, 95% CI: 1.01-2.13), religion (AOR: 0.55, 95% CI: 0.32-0.94), female household head (AOR: 1.93, 95% CI: 1.17-3.19), living in Rajshahi (AOR: 1.97, 95% CI: 0.95-4.08), being in the 'poorest' wealth category (AOR: 2.43, 95% CI: 1.45-4.07), being in the 'poorer' wealth category (AOR: 1.70, 95% CI: 1.06-2.72), being in the 'middle' wealth category (AOR: 1.76, 95% CI: 1.12-2.77), being in the 'richer' wealth category (AOR: 1.58, 95% CI: 1.02-2.44), earlier marriage preference (AOR: 15.71, 95% CI: 9.09-27.14), later marriage preference (AOR: 12.62, 95% CI: 8.82-18.06) and heard about family planning (AOR: 0.70, 95% CI: 0.47-1.04). CONCLUSIONS: In Bangladesh, the prevalence of ESI among female adolescents is a public health concern. Due to the detrimental impact of ESI on the well-being of adolescents, it is crucial that policymakers consider the factors influencing ESI that have been identified in this study when designing health strategies. The findings from this study will help the development of evidence-based effective initiatives by policymakers in collaboration with governmental and non-governmental organisations.
Assuntos
Serviços de Planejamento Familiar , Comportamento Sexual , Gravidez , Humanos , Adolescente , Feminino , Estudos Transversais , Bangladesh/epidemiologia , Escolaridade , PrevalênciaRESUMO
BACKGROUND: Long hospital stays for neonates following cardiac surgery can be detrimental to short- and long-term outcomes. Furthermore, it can impact resource allocation within heart centres' daily operations. We aimed to explore multiple clinical variables and complications that can influence and predict the post-operative hospital length of stay. METHODS: We conducted a retrospective observational review of the full-term neonates (<30 days old) who had cardiac surgery in a tertiary paediatric cardiac surgery centre - assessment of multiple clinical variables and their association with post-operative hospital length of stay. RESULTS: A total of 273 neonates were screened with a mortality rate of 8%. The survivors (number = 251) were analysed; 83% had at least one complication. The median post-operative hospital length of stay was 19.5 days (interquartile range 10.5, 31.6 days). The median post-operative hospital length of stay was significantly different among patients with complications (21.5 days, 10.5, 34.6 days) versus the no-complication group (14 days, 9.6, 19.5 days), p < 0.01. Among the non-modifiable variables, gastrostomy, tracheostomy, syndromes, and single ventricle physiology are significantly associated with longer post-operative hospital length of stay. Among the modifiable variables, deep vein thrombosis and cardiac arrest were associated with extended post-operative hospital length of stay. CONCLUSIONS: Complications following cardiac surgery can be associated with longer hospital stay. Some complications are modifiable. Deep vein thrombosis and cardiac arrest are among the complications that were associated with longer hospital stay and offer a direct opportunity for prevention which may be reflected in better outcomes and shorter hospital stay.
Assuntos
Parada Cardíaca , Trombose Venosa , Recém-Nascido , Criança , Humanos , Ponte Cardiopulmonar/efeitos adversos , Tempo de Internação , Estudos Retrospectivos , Fatores de Risco , Parada Cardíaca/etiologia , Trombose Venosa/etiologia , Complicações Pós-Operatórias/etiologiaRESUMO
A series of 16 novel spirooxindole analogs 8a-p were designed and constructed via cost-effective single-step multicomponent [3+2] cycloaddition reaction of azomethine ylide (AY) generated in situ from substituted isatin (6a-d) with suitable amino acids (7a-c) and ethylene-engrafted pyrazole derivatives (5a,b). The potency of all compounds was assayed against a human breast cancer cell line (MCF-7) and a human liver cell line (HepG2). Spiro compound 8c was the most active member among the synthesized candidates, with exceptional cytotoxicity against the MCF-7 and HepG2 cell lines, with IC50 values of 0.189 ± 0.01 and 1.04 ± 0.21 µM, respectively. The candidate 8c exhibited more potent activity (10.10- and 2.27-fold) than the standard drug roscovitine (IC50 = 1.91 ± 0.17 µM (MCF-7) and 2.36 ± 0.21 µM (HepG2)). Compound 8c was investigated for epidermal growth factor receptor (EGFR) inhibition; it exhibited promising IC50 values of 96.6 nM compared with 67.3 nM for erlotinib. The IC50 value of 8c (34.98 nM) exhibited cyclin-dependent kinase 2 (CDK-2) inhibition, being more active than roscovitine the (IC50 = 140 nM) in targeting the CDK-2 kinase enzyme. Additionally, for apoptosis induction of compound 8c in MCF-7, it upregulated the expression levels of proapoptotic genes for P53, Bax, caspases-3, 8, and 9 at up to 6.18, 4.8, 9.8, 4.6, 11.3 fold-change, respectively, and downregualted the level of the antiapoptotic gene for Bcl-2 by 0.14-fold. Finally, a molecular docking study of the most active compound 8c highlighted a good binding affinity with Lys89 as the key amino acid for CDK-2 inhibition.
Assuntos
Antineoplásicos , Humanos , Oxindóis/farmacologia , Oxindóis/química , Linhagem Celular Tumoral , Relação Estrutura-Atividade , Roscovitina/farmacologia , Simulação de Acoplamento Molecular , Antineoplásicos/química , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , ApoptoseRESUMO
This experiment assessed the influences of betaine (BET; 2000 mg/kg) on rectal temperature (Tr), laying performance, metabolism, intestinal morphology, and follicular development in heat-stressed hens. One-hundred and twenty-eight Hisex white hens (42wks) were housed in 4 battery cages (8 pens/cage; 4 hens/pen) and divided into 4 treatments: 1) thermoneutral (TN) environments and a control diet (TNCON), 2) TN and a diet accompanied with BET (TNBET), 3) heat stress (HS) environments and a control diet (HSCON), or 4) HS and a diet accompanied with BET (HSBET). Following acclimation (15d), hens of TNCON and TNBET remained in TN, while HSCON and HSBET hens were subjected to cyclical HS (5d; 16.9-37.5 °C). Cyclical HS increased Tr compared with TN hens (1.6 °C; P < 0.01), but supplemental BET decreased Tr (0.4 °C; P < 0.01). Relative to TN treatments, HS declined egg production, weight, and mass (18, 4.2, and 26%, respectively; P < 0.01), but BET ameliorated the egg production and mass (13.1 and 16.2%, respectively; P < 0.01). Compared with HSCON, feed conversion ratio and survival rate were improved in HSBET hens (12.3 and 6.25%, respectively; P ≥ 0.03). Relative to TN hens, HS elevated glucose and blood urea nitrogen (BUN) levels (15 and 4%, respectively; P ≤ 0.04). Supplemental BET decreased BUN levels (6.6%; P < 0.01) relative to HSCON hens. Furthermore, HS diminished jejunal villus height and villus surface area (â¼27 and 35%, respectively; P < 0.01) relative to TN hens but were unaltered by BET supplementation. Relative to TN hens, HS decreased oviduct's weight, ovary's length, and ovarian primordial and primary follicles count (18, 23, 34 and 44%, respectively; P < 0.01) and caused fibrosis in shell gland (3-fold; P = 0.05). Collectively, HS impaired productivity, metabolism, intestinal architecture, and reproductive efficiency. Feeding BET reduced Tr, improved laying performance, and slightly altered metabolism but did not affect intestinal and follicular measurements in heat-stressed hens.
RESUMO
Ruthenium (Ru)-based organometallic drugs have gained attention as chemotherapeutic and bioimaging agents due to their fewer side effects and excellent physical optical properties. Tuning the electronic structures of Ru complexes has been proven to increase the cytotoxicity of cancer cells and the luminescent efficiency of the analytical probes. However, the relationship between electronic structures and bioactivities is still unclear due to the potential enhancement of both electron donor and acceptor properties. Thus, we investigated the relationship between the electronic structures of Ru(II) complexes and cytotoxicity by optimizing the electron-withdrawing (complex 1), electron-neutral (complex 2), and electron-donating (complex 3) ligands through DFT calculations, bioactivities tests, and docking studies. Our results indicated that it was not sufficient to consider only either the effect of electron-withdrawing or electron-donating effects on biological activities instead of the total electronic effects. Furthermore, these complexes with electron-donating substituents (complex 3) featured unique "off-on" luminescent emission phenomena caused by the various "HOMO-LUMO" distributions when they interacted with DNA, while complex with electron-withdrawing substituent showed an "always-on" signature. These findings offer valuable insight into the development of bifunctional chemotherapeutic agents along with bioimaging ability.
Assuntos
Complexos de Coordenação , Rutênio , Rutênio/química , Piridinas/química , DNA/química , Teoria da Densidade Funcional , Complexos de Coordenação/farmacologia , Complexos de Coordenação/químicaRESUMO
1. This study was conducted to develop an efficient technique for separating double-yolked (DY) from single-yolked (SY) light brown broiler eggs with comparable shape and size, that were hard to distinguish merely by their external characteristics, using Vis-NIR transmission spectroscopy combined with multivariate analysis.2. Spectroscopic transmission (200-900 nm) was measured after collecting the eggs, and the yolk number was verified by breaking the eggs after boiling. The absorbance of important spectral wavelengths sensitive to yolk amount were identified using feature selection techniques (Principal Component Analysis and Genetic Algorithm).3. Discriminant analysis (DA) and support vector machine (SVM) classifiers were used to develop classification models for DY and SY eggs using the selected important spectral wavelengths.4. When compared to alternative nonlinear techniques, the developed model applying linear discriminant analysis produced greater accuracies in the first (96%) and second (100%) experiments, implying lower inter-egg variability from spectral data and a linear relationship between classes. However, the position and orientation of yolks in DY eggs may limit the classification accuracy of the eggs.