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1.
Microsc Res Tech ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39318246

RESUMO

This study presents a novel, environmentally sustainable method for the synthesis of graphene oxide (GO) sheets decorated uniformly with silver nanoparticles (Ag NPs) ranging in size from 4 to 34 nm. The reduction of AgNO3 is achieved using an extract derived from Cucumis callosus fruit, which serves as a dual-function stabilizing and reducing agent. Cucumis callosus, belonging to the Cucurbitaceae family and native to regions such as India, South America, Thailand, Africa, and Egypt, is recognized for its substantial nutritional and medicinal value, encompassing antioxidant, antidiabetic, anticancer, and anti-inflammatory properties. In this study, we explore the utilization of Cucumis callosus extract for the first time in synthesizing Ag NPs, employing a green synthesis approach to produce GO-Ag nanocomposites. Comprehensive characterization techniques confirm the structural integrity and quality of the synthesized nanocomposites. The antibacterial efficacy of the green-synthesized Ag-decorated GO nanocomposites was evaluated using the disk diffusion method against Bacillus subtilis (Gram-positive) and Escherichia coli (Gram-negative) bacteria at varying dosages. The nanocomposites demonstrated dose-dependent antibacterial activity against both bacterial strains, with a notably heightened effect observed against Gram-negative bacteria. These findings underscore the potential of Cucumis callosus as a promising candidate for the sustainable preparation of GO-Ag nanocomposites with enhanced antibacterial properties, suitable for various biomedical and environmental applications. RESEARCH HIGHLIGHTS: This work presents a simple, environmentally free, and cost-effective green synthesis method to decorate uniformly small (4-34 nm) spherical Ag NPs on the GO sheets. Ag NPs were produced by reducing AgNO3 using Cucumis callosus fruit extract as a stabilizing and reducing agent. The nanocomposites show dosage-dependent antibacterial activities against both Gram-positive and Gram-negative bacteria, but the antibacterial effect is higher against the Gram-negative bacteria. Synthesis of these nanocomposites via the green route using an herbal plant/fruit like Cucumis callosus will benefit the medical industry.

2.
Indian J Ophthalmol ; 72(4): 571-577, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38099368

RESUMO

PURPOSE: Corneal biopsy helps in diagnosing deep-seated or recalcitrant lesions of microbial keratitis (MK). We aim to analyze its role in managing these challenging cases. METHODS: This is a retrospective review of 22 cases of corneal biopsy at our institute from January 2010 to December 2021. Data were retrospectively collected using the electronic medical record (EMR) system. Those cases of indolent, progressive MK or deep-seated lesions where cornea scraping was not possible were considered for corneal biopsy to establish the microbiological diagnosis. The primary aims of our study were to analyze the indications, success rates, and outcomes for biopsy patients in our series. Additional outcomes that were analyzed included the average time from presentation to biopsy, the type of causative organism isolated from the biopsy by either histopathological or microbiological method, and the frequency and outcome of surgical interventions performed. Descriptive statistics using mean (±standard deviation) and median (±range) were used to interpret the demographic data. RESULTS: Overall, 15 of 22 patients (68%) had a positive corneal biopsy after microbiological or histopathological examinations. The most identified organism was microsporidia (n = 4,30.7%), followed by mycobacteria (n = 2,15.4%), gram-negative bacilli (n = 2,15.4%), acid-fast bacilli (n = 1,7.6%), fungus (n = 2,15.4%), gram-positive cocci (n = 1,7.6%), and mixed bacterial infection (n = 1,7.6%). CONCLUSION: Corneal biopsy should be considered a diagnostic modality for patients with deep-seated or unresponsive MK. It can improve the treatment for MK, ensuring targeted therapy.


Assuntos
Infecções Oculares Bacterianas , Ceratite , Humanos , Estudos Retrospectivos , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/terapia , Infecções Oculares Bacterianas/microbiologia , Ceratite/microbiologia , Córnea/patologia , Biópsia/métodos
3.
BMJ Case Rep ; 16(12)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114293

RESUMO

A patient in his sixth decade presented to us with redness, pain and a deterioration of vision in his left eye. He had previously been diagnosed with lattice corneal dystrophy (LCD). He was diagnosed with microbial keratitis, and mixed infection was confirmed on culture (bacteria and fungus) with a protracted healing period before resolution of keratitis. He presented 2 years later with similar issues in the same eye and was noted to have a second episode of microbial keratitis, with microsporidia spores noted on gram, potassium hydroxide and calcofluor white stains. He was diagnosed with microsporidial stromal keratitis and underwent therapeutic penetrating keratoplasty. Unfortunately, he suffered a recurrence of microsporidial keratitis following surgery with eventual transplant failure. Microsporidia as an infection in LCD has, to our knowledge, not been previously reported. We aim to discuss microsporidial infection and recurrent microbial keratitis in the setting of LCD.


Assuntos
Neuropatias Amiloides Familiares , Distrofias Hereditárias da Córnea , Infecções Oculares Fúngicas , Ceratite , Microsporídios , Humanos , Masculino , Córnea/microbiologia , Infecções Oculares Fúngicas/microbiologia , Ceratite/microbiologia , Pessoa de Meia-Idade , Idoso
4.
Brain Sci ; 13(12)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38137154

RESUMO

The study aimed to differentiate experts from novices in laparoscopic surgery tasks using electroencephalogram (EEG) topographic features. A microstate-based common spatial pattern (CSP) analysis with linear discriminant analysis (LDA) was compared to a topography-preserving convolutional neural network (CNN) approach. Expert surgeons (N = 10) and novice medical residents (N = 13) performed laparoscopic suturing tasks, and EEG data from 8 experts and 13 novices were analysed. Microstate-based CSP with LDA revealed distinct spatial patterns in the frontal and parietal cortices for experts, while novices showed frontal cortex involvement. The 3D CNN model (ESNet) demonstrated a superior classification performance (accuracy > 98%, sensitivity 99.30%, specificity 99.70%, F1 score 98.51%, MCC 97.56%) compared to the microstate based CSP analysis with LDA (accuracy ~90%). Combining spatial and temporal information in the 3D CNN model enhanced classifier accuracy and highlighted the importance of the parietal-temporal-occipital association region in differentiating experts and novices.

5.
Neurophotonics ; 10(2): 023521, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37152356

RESUMO

Significance: As trainees practice fundamental surgical skills, they typically rely on performance measures such as time and errors, which are limited in their sensitivity. Aim: The goal of our study was to evaluate the use of portable neuroimaging measures to map the neural processes associated with learning basic surgical skills. Approach: Twenty-one subjects completed 15 sessions of training on the fundamentals of laparoscopic surgery (FLS) suture with intracorporeal knot-tying task in a box trainer. Functional near infrared spectroscopy data were recorded using an optode montage that covered the prefrontal and sensorimotor brain areas throughout the task. Average oxy-hemoglobin (HbO) changes were determined for repetitions performed during the first week of training compared with the third week of training. Statistical differences between the time periods were evaluated using a general linear model of the HbO changes. Results: Average performance scores across task repetitions increased significantly from the first day to the last day of training ( p < 0.01 ). During the first day of training, there was significant lateral prefrontal cortex (PFC) activation. On the final day, significant activation was observed in the PFC, as well as the sensorimotor areas. When comparing the two periods, significant differences in activation ( p < 0.05 ) were found for the right medial PFC and the right inferior parietal gyrus. While gaining proficiency, trainees activated the perception-action cycle to build a perceptual model and then apply the model to improve task execution. Conclusions: Learners engaged the sensorimotor areas more substantially as they developed skill on the FLS suturing task. These findings are consistent with findings for the FLS pattern cutting task and contribute to the development of objective metrics for skill evaluation.

6.
Indian J Ophthalmol ; 71(5): 1877-1881, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37203048

RESUMO

Purpose: This study aims to analyze the pattern of follow-ups and the reasons for follow-up loss in keratoplasty cases in a tertiary eye care center. Methods: This is a single-center retrospective cross-sectional study. During the study period, 165 eyes underwent corneal transplantation. The data on the demographic features of the recipients and the indications of keratoplasty, including visual acuity before and after surgery, duration of follow-up, and the condition of the graft at the last follow-up, were collected. The primary outcome was to determine the factors causing lost-to-follow-up (LTFU) among graft recipients. LTFU was defined when a patient failed to adhere to any of the following seven follow-up visits since the surgery: 4 ± 2 weeks, 3 ± 1 months, 6 ± 1 months, 12 ± 2 months, 18 ± 2 months, 24 ± 3 months, and 36 ± 6 months. The secondary outcome was to analyze the best-corrected visual acuity (BCVA) among patients available for the final follow-up. Results: The recipient follow-up rates at 6, 12, 18, 24, and 36 months were 68.5%, 57.6%, 47.9%, 42.4%, and 35.2%, respectively. Old age and distance to the center were significant factors for lost-to-follow-up. A failed graft as an indication for transplantation and those undergoing penetrating keratoplasty for optical purposes were significant factors for completing follow-up. Conclusion: The inability to follow-up after corneal transplantation is a common challenge. Elderly patients and those living in remote areas must be prioritized for follow-ups.


Assuntos
Doenças da Córnea , Transplante de Córnea , Humanos , Idoso , Doenças da Córnea/diagnóstico , Doenças da Córnea/cirurgia , Estudos Retrospectivos , Estudos Transversais , Resultado do Tratamento , Ceratoplastia Penetrante , Índia/epidemiologia , Seguimentos , Sobrevivência de Enxerto
7.
Autops Case Rep ; 13: e2023426, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37101551

RESUMO

Chronic myeloid leukemia (CML) accounts for 2-3% of childhood leukemias. About 5% of cases present in a blastic phase of CML which clinically and morphologically mimics more common acute leukemias of childhood. We report a case of a 3-year-old male who presented with gradual onset swelling of the abdomen and extremities along with generalized weakness. Examination revealed massive splenomegaly, pallor, and pedal edema. Initial workup showed anemia, thrombocytopenia, and leukocytosis (120,000/uL) with a blast percentage of 35%. Blasts were positive for CD13, CD33, CD117, CD34 and HLA-DR, and stained negative for Myeloperoxidase and Periodic Acid Schiff. Fluorescence in situ hybridization was positive for b3a2/e14a2 junction BCR-ABL1 transcript and negative for RUNX1-RUNX1T1/t(8;21), clinching the diagnosis of CML in myeloid blast crisis. The patient expired within 17 days of diagnosis and initiation of therapy.

8.
Surg Endosc ; 37(7): 5576-5582, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36316582

RESUMO

BACKGROUND: The goal of this study was to compare the brain activation patterns of experienced and novice individuals when performing the Fundamentals of Laparoscopic Surgery (FLS) suture with intracorporeal knot tying task, which requires bimanual motor control. METHODS: Twelve experienced and fourteen novice participants completed this cross-sectional observational study. Participants performed three repetitions of the FLS suture with intracorporeal knot tying task in a standard box trainer. Functional near infrared spectroscopy (fNIRS) data was recorded using an optode montage that covered the prefrontal and sensorimotor brain areas throughout the task. Data processing was conducted using the HOMER3 and AtlasViewer toolboxes to determine the oxy-hemoglobin (HbO) and deoxyhemoglobin (HbR) concentrations. The hemodynamic response function based on HbO changes during the task relative to the resting state was averaged for each repetition and by participant. Group-level differences were evaluated using a general linear model of the HbO changes with significance set at p < 0.05. RESULTS: The average performance score for the experienced group was significantly higher than the novice group (p < 0.01). There were significant cortical activations (p < 0.05) in the prefrontal and sensorimotor areas for the experienced and novice groups. Areas of statistically significant differences in activation included the right dorsolateral prefrontal cortex (PFC), the right precentral gyrus, and the right postcentral gyrus. CONCLUSIONS: Portable neuroimaging allowed for the differentiation of brain regions activated by experienced and novice participants for a complex surgical motor task. This information can be used to support the objective evaluation of expertise during surgical skills training and assessment.


Assuntos
Laparoscopia , Humanos , Estudos Transversais , Laparoscopia/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Suturas , Neuroimagem , Técnicas de Sutura/educação , Competência Clínica
9.
Food Chem ; 407: 135179, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36521392

RESUMO

Matrix effect (ME) is unavoidable in multiresidue pesticide analysis, even when using highly advanced instruments, and differences in MEs can affect residue analytical accuracy due to pomegranate cultivar composition variations. However, literature to support this claim is limited.The study used GC-MS/MS and LC-MS/MS to investigate four different Indian pomegranate cultivar extracts and their MEs on multi-class pesticides.The whole fruit and arils of all cultivarswere tested for 22 GC-amenable and 21 LC-amenable pesticides. Principal component analysis of the data confirmed that each cultivar had unique MEs for each pesticide.The majority of pesticides showed acute variations in recovery rates with 95% confidence, while GC-MS/MS-amenablepesticides showed more variation. Although extrapolative dilution reduced the influence of MEs on analytical accuracy, a generalized matrix-matching for all cultivars was not possible to achieve.To reduce the variability in MEs, it is recommended that a cultivar-specific matrix-matched standard should be used.


Assuntos
Resíduos de Praguicidas , Praguicidas , Punica granatum , Espectrometria de Massas em Tandem , Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas , Cromatografia Líquida , Frutas/química , Resíduos de Praguicidas/análise
10.
Front Neurogenom ; 4: 1135729, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38234492

RESUMO

Transcranial Direct Current Stimulation (tDCS) has demonstrated its potential in enhancing surgical training and performance compared to sham tDCS. However, optimizing its efficacy requires the selection of appropriate brain targets informed by neuroimaging and mechanistic understanding. Previous studies have established the feasibility of using portable brain imaging, combining functional near-infrared spectroscopy (fNIRS) with tDCS during Fundamentals of Laparoscopic Surgery (FLS) tasks. This allows concurrent monitoring of cortical activations. Building on these foundations, our study aimed to explore the multi-modal imaging of the brain response using fNIRS and electroencephalogram (EEG) to tDCS targeting the right cerebellar (CER) and left ventrolateral prefrontal cortex (PFC) during a challenging FLS suturing with intracorporeal knot tying task. Involving twelve novices with a medical/premedical background (age: 22-28 years, two males, 10 females with one female with left-hand dominance), our investigation sought mechanistic insights into tDCS effects on brain areas related to error-based learning, a fundamental skill acquisition mechanism. The results revealed that right CER tDCS applied to the posterior lobe elicited a statistically significant (q < 0.05) brain response in bilateral prefrontal areas at the onset of the FLS task, surpassing the response seen with sham tDCS. Additionally, right CER tDCS led to a significant (p < 0.05) improvement in FLS scores compared to sham tDCS. Conversely, the left PFC tDCS did not yield a statistically significant brain response or improvement in FLS performance. In conclusion, right CER tDCS demonstrated the activation of bilateral prefrontal brain areas, providing valuable mechanistic insights into the effects of CER tDCS on FLS peformance. These insights motivate future investigations into the effects of CER tDCS on error-related perception-action coupling through directed functional connectivity studies.

11.
Autops. Case Rep ; 13: e2023426, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1429897

RESUMO

ABSTRACT Chronic myeloid leukemia (CML) accounts for 2-3% of childhood leukemias. About 5% of cases present in a blastic phase of CML which clinically and morphologically mimics more common acute leukemias of childhood. We report a case of a 3-year-old male who presented with gradual onset swelling of the abdomen and extremities along with generalized weakness. Examination revealed massive splenomegaly, pallor, and pedal edema. Initial workup showed anemia, thrombocytopenia, and leukocytosis (120,000/uL) with a blast percentage of 35%. Blasts were positive for CD13, CD33, CD117, CD34 and HLA-DR, and stained negative for Myeloperoxidase and Periodic Acid Schiff. Fluorescence in situ hybridization was positive for b3a2/e14a2 junction BCR-ABL1 transcript and negative for RUNX1-RUNX1T1/t(8;21), clinching the diagnosis of CML in myeloid blast crisis. The patient expired within 17 days of diagnosis and initiation of therapy.

12.
Brain Inform ; 9(1): 29, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36484977

RESUMO

Error-based learning is one of the basic skill acquisition mechanisms that can be modeled as a perception-action system and investigated based on brain-behavior analysis during skill training. Here, the error-related chain of mental processes is postulated to depend on the skill level leading to a difference in the contextual switching of the brain states on error commission. Therefore, the objective of this paper was to compare error-related brain states, measured with multi-modal portable brain imaging, between experts and novices during the Fundamentals of Laparoscopic Surgery (FLS) "suturing and intracorporeal knot-tying" task (FLS complex task)-the most difficult among the five psychomotor FLS tasks. The multi-modal portable brain imaging combined functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG) for brain-behavior analysis in thirteen right-handed novice medical students and nine expert surgeons. The brain state changes were defined by quasi-stable EEG scalp topography (called microstates) changes using 32-channel EEG data acquired at 250 Hz. Six microstate prototypes were identified from the combined EEG data from experts and novices during the FLS complex task that explained 77.14% of the global variance. Analysis of variance (ANOVA) found that the proportion of the total time spent in different microstates during the 10-s error epoch was significantly affected by the skill level (p < 0.01), the microstate type (p < 0.01), and the interaction between the skill level and the microstate type (p < 0.01). Brain activation based on the slower oxyhemoglobin (HbO) changes corresponding to the EEG band power (1-40 Hz) changes were found using the regularized temporally embedded Canonical Correlation Analysis of the simultaneously acquired fNIRS-EEG signals. The HbO signal from the overlying the left inferior frontal gyrus-opercular part, left superior frontal gyrus-medial orbital, left postcentral gyrus, left superior temporal gyrus, right superior frontal gyrus-medial orbital cortical areas showed significant (p < 0.05) difference between experts and novices in the 10-s error epoch. We conclude that the difference in the error-related chain of mental processes was the activation of cognitive top-down attention-related brain areas, including left dorsolateral prefrontal/frontal eye field and left frontopolar brain regions, along with a 'focusing' effect of global suppression of hemodynamic activation in the experts, while the novices had a widespread stimulus(error)-driven hemodynamic activation without the 'focusing' effect.

13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 941-944, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36083946

RESUMO

Fundamentals of Laparoscopic Surgery (FLS) is a standard education and training module with a set of basic surgical skills. During surgical skill acquisition, novices need to learn from errors due to perturbations in their performance which is one of the basic principles of motor skill acquisition. This study on thirteen healthy novice medical students and nine expert surgeons aimed to capture the brain state during error epochs using multimodal brain imaging by combining functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG). We performed error-related microstate analysis in the latent space that was found using regularized temporally embedded Canonical Correlation Analysis from fNIRS-EEG recordings during the performance of FLS "suturing and intracorporeal knot-tying" task - the most difficult among the five psychomotor FLS tasks. We found from two-way analysis of variance (ANDVA) with factors, skill level (expert, novice), and microstate type (1-6) that the proportion of the total time spent in microstates in the error epochs was significantly affected by the skill level ( ), microstate type ( ), and the interaction between the skill level and the microstate type ( ). Therefore, our study highlighted the relevance of portable brain imaging to capture error behavior when comparing the skill level during a complex surgical task. Clinical Relevance-This establishes the brain-behavior relationship for monitoring complex surgical motor task errors that differentiated experts from novices.


Assuntos
Laparoscopia , Cirurgiões , Eletroencefalografia , Humanos , Laparoscopia/educação , Técnicas de Sutura/educação , Suturas
14.
NPJ Sci Learn ; 7(1): 19, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008451

RESUMO

Virtual reality (VR) simulator has emerged as a laparoscopic surgical skill training tool that needs validation using brain-behavior analysis. Therefore, brain network and skilled behavior relationship were evaluated using functional near-infrared spectroscopy (fNIRS) from seven experienced right-handed surgeons and six right-handed medical students during the performance of Fundamentals of Laparoscopic Surgery (FLS) pattern of cutting tasks in a physical and a VR simulator. Multiple regression and path analysis (MRPA) found that the FLS performance score was statistically significantly related to the interregional directed functional connectivity from the right prefrontal cortex to the supplementary motor area with F (2, 114) = 9, p < 0.001, and R2 = 0.136. Additionally, a two-way multivariate analysis of variance (MANOVA) found a statistically significant effect of the simulator technology on the interregional directed functional connectivity from the right prefrontal cortex to the left primary motor cortex (F (1, 15) = 6.002, p = 0.027; partial η2 = 0.286) that can be related to differential right-lateralized executive control of attention. Then, MRPA found that the coefficient of variation (CoV) of the FLS performance score was statistically significantly associated with the CoV of the interregionally directed functional connectivity from the right primary motor cortex to the left primary motor cortex and the left primary motor cortex to the left prefrontal cortex with F (2, 22) = 3.912, p = 0.035, and R2 = 0.262. This highlighted the importance of the efference copy information from the motor cortices to the prefrontal cortex for postulated left-lateralized perceptual decision-making to reduce behavioral variability.

15.
Appl Environ Microbiol ; 88(15): e0059622, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35862686

RESUMO

The human microbiota, which comprises an ensemble of taxonomically and functionally diverse but often mutually cooperating microorganisms, benefits its host by shaping the host immunity, energy harvesting, and digestion of complex carbohydrates as well as production of essential nutrients. Dysbiosis in the human microbiota, especially the gut microbiota, has been reported to be linked to several diseases and metabolic disorders. Recent studies have further indicated that tracking these dysbiotic variations could potentially be exploited as biomarkers of disease states. However, the human microbiota is not geography agnostic, and hence a taxonomy-based (microbiome) biomarker for disease diagnostics has certain limitations. In comparison, (microbiome) function-based biomarkers are expected to have a wider applicability. Given that (i) the host physiology undergoes certain changes in the course of a disease and (ii) host-associated microbial communities need to adapt to this changing microenvironment of their host, we hypothesized that signatures emanating from the abundance of bacterial proteins associated with the signal transduction system (herein referred to as sensory proteins [SPs]) might be able to distinguish between healthy and diseased states. To test this hypothesis, publicly available metagenomic data sets corresponding to three diverse health conditions, namely, colorectal cancer, type 2 diabetes mellitus, and schizophrenia, were analyzed. Results demonstrated that SP signatures (derived from host-associated metagenomic samples) indeed differentiated among healthy individual and patients suffering from diseases of various severities. Our finding was suggestive of the prospect of using SP signatures as early biomarkers for diagnosing the onset and progression of multiple diseases and metabolic disorders. IMPORTANCE The composition of the human microbiota, a collection of host-associated microbes, has been shown to differ among healthy and diseased individuals. Recent studies have investigated whether tracking these variations could be exploited for disease diagnostics. It has been noted that compared to microbial taxonomies, the ensemble of functional proteins encoded by microbial genes are less likely to be affected by changes in ethnicity and dietary preferences. These functions are expected to help the microbe adapt to changing environmental conditions. Thus, healthy individuals might harbor a different set of genes than diseased individuals. To test this hypothesis, we analyzed metagenomes from healthy and diseased individuals for signatures of a particular group of proteins called sensory proteins (SP), which enable the bacteria to sense and react to changes in their microenvironment. Results demonstrated that SP signatures indeed differentiate among healthy individuals and those suffering from diseases of various severities.


Assuntos
Diabetes Mellitus Tipo 2 , Microbiota , Biomarcadores , Disbiose , Humanos , Metagenoma
16.
Front Plant Sci ; 13: 874221, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35574070

RESUMO

The present study aimed to develop nanoemulsions (NEs) of essential oil (EO) and lipid-soluble extract (HE) of Pogostemon cablin leaves using biosurfactant, saponin. Hydro-distilled EO and fat-soluble HE were analyzed using GC-MS, which revealed 38.7 ± 2.7% and 37.5 ± 2.1% patchoulol, respectively. EO and HE were formulated with saponin to prepare corresponding coarse emulsions (CEs); furthermore, high-speed homogenization for 2 min was followed by ultrasonication for 3 min with constant frequency of 50 kHz. of the CEs resulted in respective NEs. NEs were characterized for the physico-chemical properties such as emulsion intrinsic stability, particle size distribution, polydispersity index (PDI), and transmission electron microscopy (TEM) for morphology and accurate nanodroplet diameters. CEs and NEs were investigated for insecticidal efficacy against adults of Tetranychus urticae and larvae of Spodoptera litura. Stable NEs of EO and HE at 500 µg mL-1 concentration exhibited corresponding average particle size of 51.7 and 89.9 nm, while TEM image revealed spherical-shaped droplets with the average droplet diameters of 15.3 and 29.4 nm, respectively. NEs of EO and HE displayed highest efficacy in contact toxicity (LC50 43.2 and 58.4 µg mL-1) after 48 h and fumigant toxicity (LC50 9.3 and 13.6 µg mL-1) after 24 h against T. urticae. In addition, NEs of EO showed considerable antifeedant and feeding deterrent action (AI 99.21 ± 0.74 and FI 99.73 ± 1.24) against S. litura larvae.

17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 7437-7440, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892815

RESUMO

Fundamentals of Laparoscopic Surgery (FLS) is a prerequisite for board certification in general surgery in the USA. In FLS, the suturing task with intracorporeal knot tying is considered the most complex task. Transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex (PFC) has been shown to facilitate FLS surgical skill acquisition where 2mA tDCS for 15min with the anode over F3 (10/10 EEG montage) and cathode over F4 has improved performance score in an open knot-tying task. Since PFC has a functional organization related to the hierarchy of cognitive control, we performed functional near-infrared spectroscopy (fNIRS) to investigate PFC sub-domain activation during a more complex FLS suturing task with intracorporeal knot tying. We performed fNIRS-based analysis using AtlasViewer software on two expert surgeons and four novice medical students. We found an average cortical activation mainly at the left frontopolar PFC across the experts, while the average cortical activation across the novices was primarily at the left pars opercularis of the inferior frontal gyrus and ventral premotor cortex, inferior parietal lobule, and supramarginal gyrus. Here, the average cortical activation across the novices included not only the cognitive control related brain regions but also motor control complexity related brain regions. Therefore, we present a computational pipeline to identify a 4x1 high-definition (HD) tDCS montage of motor complexity related PFC sub-regions using ROAST software.Clinical Relevance-A computational pipeline for fNIRS-guided tES to individualize electrode montage that may facilitate FLS surgical training in our future studies.


Assuntos
Laparoscopia , Estimulação Transcraniana por Corrente Contínua , Córtex Pré-Frontal Dorsolateral , Humanos , Neuroimagem , Espectroscopia de Luz Próxima ao Infravermelho
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 1014-1017, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891460

RESUMO

this study investigates the difference in effective connectivity among novice medical students trained on physical and virtual simulators to perform the Fundamental laparoscopic surgery (FLS) pattern cutting task (PC). We propose using dynamic spectral Granger causality (GC) in the frequency band of [0.01-0.07]Hz to measure the effect of surgical training on effective brain connectivity. To obtain the dynamics relationship between the cortical regions, we propose to use the short-time Fourier transform (STFT) method. FLS pattern cutting is a complex bimanual task requiring fine motor skills and increased brain activity. With this in mind, we have used high resolution functional near-infrared spectroscopy to leverage its high temporal resolution for capturing the change in hemodynamics (HbO2) in 14 healthy subjects. Analysis of variance (ANOVA) found a statistically significant difference in "LPMC granger causes RPMC" (LPMC→ RPMC) in the subject trained on these two simulator in the first 40 sec of the task. We showed that the directed brain connectivity was affected by the type of surgical simulator used for training the medical students.


Assuntos
Laparoscopia , Estudantes de Medicina , Encéfalo/cirurgia , Competência Clínica , Humanos , Exame Físico
19.
J Environ Sci Health B ; 56(12): 1007-1022, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34779690

RESUMO

The present study was aimed to examine the antibacterial potential of Brassica nigra essential oil (BNEO) against Ralstonia solanacearum, causal agent of bacterial wilt and Nitrosomonas sp., the nitrifying bacteria. In poisoned food assay, BNEO showed 100% growth inhibition of R. solancearum at ≥ 125 µg mL-1. Revalidation of findings by volatile assay employing inverted Petri plate technique exhibited 100% bacterial growth inhibition caused by vapors of BNEO, even at 50 µg mL-1 concentration. In the broth microdilution assay, the BNEO exhibited significant antibacterial activity only at higher concentrations (>500 µg mL-1). At 500 µg mL-1, BNEO showed 80% bacterial growth inhibition over control, which was at par with that of streptomycin (5 µg mL-1). In resazurin microtitre-plate assay, the maximum concentration of BNEO, at which color change occurred was 512 µg mL-1 (T9), and thus 512 µg mL-1 was concluded as the minimum inhibitory concentration (MIC). BNEO effectively inhibited the activity of Nitrosomonas spp. with 30-65% nitrification inhibition at the dose of 400 mkg-1 of Urea-N. Homology modeled protein targets assisted computational tool-based novel analysis helped to understand that the antibacterial potency of BNEO is due to preferable binding efficiency of allyl isothiocyanate (AITC), the major active ingredient of BNEO.


Assuntos
Óleos Voláteis , Ralstonia solanacearum , Antibacterianos/farmacologia , Bactérias , Testes de Sensibilidade Microbiana , Mostardeira , Óleos Voláteis/farmacologia
20.
Front Plant Sci ; 12: 714730, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512695

RESUMO

Environmental concerns related to synthetic pesticides and the emphasis on the adoption of an integrated pest management concept as a cardinal principle have strengthened the focus of global research and development on botanical pesticides. A scientific understanding of the mode of action of biomolecules over a range of pests is key to the successful development of biopesticides. The present investigation focuses on the in silico protein-ligand interactions of allyl isothiocyanate (AITC), a major constituent of black mustard (Brassica nigra) essential oil (MEO) against two pests, namely, Meloidogyne incognita (Mi) and Fusarium oxysporum f. sp. lycopersici (Fol), that cause severe yield losses in agricultural crops, especially in vegetables. The in vitro bioassay results of MEO against Mi exhibited an exposure time dependent on the lethal concentration causing 50% mortality (LC50) values of 47.7, 30.3, and 20.4 µg ml-1 at 24, 48, and 72 h of exposure, respectively. The study revealed short-term nematostatic activity at lower concentrations, with nematicidal activity at higher concentrations upon prolonged exposure. Black mustard essential oil displayed excellent in vitro Fol mycelial growth inhibition, with an effective concentration to cause 50% inhibition (EC50) value of 6.42 µg ml-1. In order to decipher the mechanism of action of MEO, its major component, AITC (87.6%), which was identified by gas chromatography-mass spectrometry (GC-MS), was subjected to in silico docking and simulation studies against seven and eight putative target proteins of Mi and Fol, respectively. Allyl isothiocyanate exhibited the highest binding affinity with the binding sites of acetyl cholinesterase (AChE), followed by odorant response gene-1 (ODR1) and neuropeptide G-protein coupled receptor (nGPCR) in Mi, suggesting the possible suppression of neurotransmission and chemosensing functions. Among the target proteins of Fol, AITC was the most effective protein in blocking chitin synthase (CS), followed by 2,3-dihydroxy benzoic acid decarboxylase (6m53) and trypsinase (1try), thus inferring these as the principal molecular targets of fungal growth. Taken together, the study establishes the potential of MEO as a novel biopesticide lead, which will be utilized further to manage the Mi-Fol disease complex.

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