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1.
Langmuir ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38845184

RESUMO

The nucleation mechanism of bulk nanobubbles remains unclear despite the considerable attention they have received in recent years. We propose two hypotheses: (i) The gas supersaturation in the bulk liquid is the primary factor for nanobubble nucleation, and (ii) the mixing of the same solvent at varying gas solubilities should produce nanobubbles, provided that the first hypothesis is correct. To test this hypothesis, we performed extensive experiments on nanobubble nucleation in both water and organic solvents. The temperature difference between hot and cold samples ranged from 10 to 80 °C in pure solvents such as water, methanol, ethanol, propanol, and butanol prepared and mixed in equal proportions. To the best of our knowledge, we report bulk nanobubble nucleation by mixing hot and cold solvents for the first time. The refractive index value calculations using Mie scattering theory confirmed the existence of nanobubbles. When surface tension dominates over surface charge, the critical work for nanobubble formation is ΔFc ∝ 1/ξ2, and when surface charge dominates over surface tension, the critical work is ΔFc ∝ ξ1/4. Our experimental results verify such dependency by measuring nanobubbles nucleated with varying degrees of gas supersaturation.

2.
Radiol Case Rep ; 19(7): 2832-2836, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38689818

RESUMO

Pericardial hydatid cysts, although rare, present unique diagnostic challenges and require a multidisciplinary approach for effective management. This parasitic infection, caused by Echinococcus granulosus larvae, typically affects the liver and lungs but can manifest in the pericardium, leading to potentially life-threatening complications if untreated. The 22-year-old female's escalating dyspnea posed diagnostic challenges despite inconclusive echocardiography. Employing a multidisciplinary strategy, including preoperative albendazole therapy and surgical excision, effectively managed the condition. This case highlights the intricate diagnostic nature of pericardial hydatid cysts, emphasizing the importance of heightened clinical awareness, especially in endemic regions. The detailed clinical trajectory, imaging methodologies, and therapeutic interventions contribute significant insights to the medical community. The study aims to deepen comprehension and guide clinicians in refined diagnostic and treatment approaches for pericardial hydatid cysts, ultimately improving patient outcomes. It underscores the imperative for continued research in this niche to enhance medical understanding and optimize clinical practices.

3.
J Basic Microbiol ; 64(3): e2300461, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38115562

RESUMO

Fungal communities colonizing Ophiocordyceps spp. plays a crucial ecological role in their natural habitat, contributing to infect the host larvae, and influencing their occurrence. Although associated fungi with the newly described Ophiocordyceps indica, from the Indian Western Himalaya remains unclear. Therefore, we untangled the culturable fungal communities associated with O. indica and soil adhered to it, collected from low-height areas of Himachal Pradesh, India. The study resulted in the identification of 111 fungal isolates representing 17 families, with maximum fungal isolates (36.03%) within Cordycipitaceae. Interestingly, a total of 24 genera were found associated with O. indica and adhered soil, of which 12 were common, 8 were exclusive to O. indica and 4 were only limited to soil. Additionally, the influence of soil physicochemical parameters on fungal diversity indices revealed a positive correlation with humidity and available nitrogen and a negative correlation with pH and available phosphorus. These findings provide insights into the culturable fungal diversity of O. indica and the soil adhering to it, thus can contribute to the understanding of host-microbial interactions. Furthermore, these associations can be explored as a source of bioactive metabolites to combat the unending industrial demands.


Assuntos
Hypocreales , Micobioma , Humanos , Himalaia , Ecossistema , Solo , Microbiologia do Solo
4.
Front Microbiol ; 14: 1188649, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547690

RESUMO

Ophiocordyceps is a species-rich genus in the order Hypocreales (Sordariomycetes, Ascomycota) depicting a fascinating relationship between microbes and insects. In the present study, a new species, Ophiocordyceps indica sp. nov., is discovered infecting lepidopteran larvae from tree line locations (2,202-2,653 m AMSL) of the Kullu District, Himachal Pradesh, Indian Western Himalayan region, using combinations of morphological and molecular phylogenetic analyses. A phylogeny for Ophiocordyceps based on a combined multigene (nrSSU, nrLSU, tef-1α, and RPB1) dataset is provided, and its taxonomic status within Ophiocordycipitaceae is briefly discussed. Its genome size (~59 Mb) revealed 94% genetic similarity with O. sinensis; however, it differs from other extant Ophiocordyceps species based on morphological characteristics, molecular phylogenetic relationships, and genetic distance. O. indica is identified as the second homothallic species in the family Ophiocordycipitaceae, after O. sinensis. The presence of targeted marker components, viz. nucleosides (2,303.25 µg/g), amino acids (6.15%), mannitol (10.13%), and biological activity data, suggests it to be a new potential source of nutraceutical importance. Data generated around this economically important species will expand our understanding regarding the diversity of Ophiocordyceps-like taxa from new locations, thus providing new research avenues.

5.
Environ Pollut ; 326: 121468, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36958654

RESUMO

This work systematically describes arsenic mobility and potential bioaccessibility of arsenic-enriched titanium dioxide water treatment residuals (TiO2 WTRs) by employing a suite of wet chemical experiments and spectroscopic measurements. Specifically, Environmental Protection Agency (EPA) digestion method 3051a indicated <3% of total arsenic in the solid phase was released, and arsenic assessed by EPA method 1340 for bioaccessibility was below detection limits. A novel finding is while the arsenic appeared to be stable under highly acidic digestion conditions, it is in fact highly mobile when exposed to simple phosphate solutions. On average, 55% of arsenic was extracted from all samples during a 50-day replenishment study. This was equivalent to 169 mg kg-1 arsenic released from the solid phase. Macroscopic desorption experiments indicated arsenic likely formed inner-sphere bonds with the TiO2 particles present in the samples. This was confirmed with X-ray absorption spectroscopy (XAS), where an interatomic distance of 3.32 Å and a coordination number (CN) of 1.79 titanium atoms were determined. This translates to a configuration of arsenic on TiO2 surfaces as a bidentate binuclear inner-sphere complex. Thus, both macroscopic and spectroscopic data are in agreement. During incubation experiments, arsenic(V) was actively reduced to arsenic(III); the amount of arsenic(III) in solution varied from 8 to 38% of total dissolved arsenic. Lastly, elevated concentrations and mobility of vanadium in these systems merit further investigation. The high mobility of arsenic and its potential for reduction when reintroduced into the environment, particularly in agriculturally important areas, presents an important risk when waste products are not properly managed.


Assuntos
Arsênio , Purificação da Água , Arsênio/química , Titânio/química , Adsorção , Purificação da Água/métodos , Espectroscopia por Absorção de Raios X
6.
Sci Total Environ ; 864: 161009, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36549526

RESUMO

Mining is an important component of the Brazilian economy. However, it may also contribute to environmental problems such as the pollution of soils with zinc and other potentially toxic metals. Our objective was to evaluate changes in the chemical speciation and mobility of Zn in a soil amended with phosphate. Soil samples were collected from a deactivated mining area in the state of Minas Gerais, Brazil, and amended with NH4H2PO4 saturated with deionized water to 70 % of maximum water retention and incubated at 25 ± 2 °C in open containers for 60 days. The soil was chemically and mineralogically characterized, and sequential extraction, desorption kinetics, and speciation were carried out using synchrotron bulk-sample and micro-X-ray Absorption Near-Edge Structure (XANES/µ-XANES) spectroscopy at the Zn K-edge, and X-ray fluorescence microprobe analysis (µ-XRF). The combination of µ-XRF and µ-XANES techniques made it possible to identify Zn hotspots in the main species formed after phosphate remediation. The best fit combination for bulk XANES and µ-XANES was observed in Zn-montmorillonite, Zn-kerolite, Zn-ferrihydrite, and gahnite. In the course of phosphate treatment, gahnite, Zn layered double hydroxides (Zn-LDH), Zn3(PO4), and ZnO were identified by bulk XANES, while Zn-ferrihydrite, Zn-montmorillonite, and scholzite were identified by µ-XANES. Zinc in the phosphate-amended soil had the strongest partial correlations (r' > 0.05) with Ni, Co, Fe, Cr, Mn, Si, P, Cd, Pb, and Cd, while the unamended soil showed the strongest correlation with Cu, Pb, Fe, and Si. The application of NH4H2PO4 altered Zn speciation and favored an increase in Zn desorption. The most available Zn contents after phosphate amendment were correlated with the release of exchangeable Zn fractions, associated with carbonate and organic matter.

7.
Sensors (Basel) ; 22(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36501845

RESUMO

With recent advancements in artificial intelligence (AI) and next-generation communication technologies, the demand for Internet-based applications and intelligent digital services is increasing, leading to a significant rise in cyber-attacks such as Distributed Denial-of-Service (DDoS). AI-based DoS detection systems promise adequate identification accuracy with lower false alarms, significantly associated with the data quality used to train the model. Several works have been proposed earlier to select optimum feature subsets for better model generalization and faster learning. However, there is a lack of investigation in the existing literature to identify a common optimum feature set for three main AI methods: machine learning, deep learning, and unsupervised learning. The current works are compromised either with the variation of the feature selection (FS) method or limited to one type of AI model for performance evaluation. Therefore, in this study, we extensively investigated and evaluated the performance of 15 individual FS methods from three major categories: filter-based, wrapper-based, and embedded, and one ensemble feature selection (EnFS) technique. Furthermore, the individual feature subset's quality is evaluated using supervised and unsupervised learning methods for extracting a common best-performing feature subset. According to our experiment, the EnFS method outperforms individual FS and provides a universal best feature set for all kinds of AI models.


Assuntos
Algoritmos , Inteligência Artificial , Aprendizado de Máquina
8.
Emerg Med Australas ; 34(4): 492-503, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35695047

RESUMO

Recreational nitrous oxide (N2 O) use is widespread, and complications associated with its use are increasingly common. We sought to identify risk factors, clinical features and outcomes in individuals presenting with effects of chronic N2 O abuse to develop an approach to clinical assessment and management. A systemic literature review was completed with searches conducted across EMBASE, MEDLINE, PSYCINFO and Cochrane databases. Our search strategy identified 612 studies, 105 met inclusion criteria, and 10 were added via hand search. Subjects from 24 case series and 91 case reports were typically in their 20s, using over 100 bulbs daily for several months. Neurological presentations, including sensory change, gait disturbance or weakness, were characteristic. Serum Vitamin B12 was normal or raised in 133 out of 243 case series subjects and 37 out of 84 reports. Serum homocysteine and methylmalonic acid were usually raised. Macrocytosis and anaemia were not commonly seen. MRI findings were abnormal with dorsal column change where specified, typically involving the cervical spine. Nerve conduction studies mostly reported a sensorimotor polyneuropathy. B12 replacement was the treatment of choice and partial recovery was most reported. This review highlights the dose-dependent nature of chronic N2 O toxicity and recognises functional B12 deficiency as the cause. As B12 is often normal, homocysteine and methylmalonic acid are important biomarkers of disease. An approach to diagnosis is offered but requires validation in prospective studies. Research exploring B12 and methionine therapy is required to refine management.


Assuntos
Óxido Nitroso , Deficiência de Vitamina B 12 , Homocisteína/uso terapêutico , Humanos , Ácido Metilmalônico/uso terapêutico , Óxido Nitroso/efeitos adversos , Estudos Prospectivos , Vitamina B 12/uso terapêutico , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 12/diagnóstico , Deficiência de Vitamina B 12/tratamento farmacológico
9.
J Anaesthesiol Clin Pharmacol ; 38(1): 79-83, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35706624

RESUMO

Background and Aims: The objective of the study was to compare duration of analgesia of fentanyl versus butorphanol as adjuvants to bupivacaine in spinal anesthesia. Material and Methods: A prospective, randomized, double-blinded study conducted in 80 patients of 18-75 years age group and American Society of Anesthesiologists Grades I and II undergoing joint replacement surgeries. A total of 40 patients in each Group A and Group B received 0.5% bupivacaine 3 ml with 25 mcg fentanyl and 25 mcg butorphanol respectively, in a total volume of 3.5 ml made with saline. Duration of analgesia, number of rescue analgesia, sensory, and motor block characteristics were compared between the two groups. Statistical analysis was done using t test and Chi-square test with SPSS 19.0 software. Results: Mean duration of analgesia was found more in Group B in comparison to Group A (P < 0.05). A number of doses of analgesic required postoperatively were more in Group A compared to Group B (P < 0.001). Time required for onset of sensory and motor block was comparable in both the groups. However, two segment regression of sensory block was slower in Group B compared to Group A (P < 0.05). Conclusion: We conclude that addition of butorphanol 25 µg as an adjuvant to 0.5% hyperbaric bupivacaine provided prolonged duration of analgesia compared to 25 mg fentanyl.

10.
Environ Sci Process Impacts ; 24(7): 1037-1049, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35723229

RESUMO

Surface precipitation has been shown to occur on rapid time scales in clay and metal oxide mineral systems. The formation of surface precipitates is hypothesized to present new potential sorption sites for potassium (K), where K can become incorporated into newly formed interlayer spaces (e.g., between tetrahedral-octahedral-tetrahedral stacked sheets). The objective of this study is to determine the effects of newly formed mineral surface precipitates on K sorption. Potassium adsorption experiments were conducted by utilizing Al2O3 and SiO2 sorbents in the presence of various cations (magnesium, zinc, and nickel) that helped to catalyze the formation of surface precipitates. Dissolved concentrations of elements were monitored via inductively coupled plasma optical emission spectrometry (ICP-OES). Solids were characterized via X-ray diffraction (XRD), and K surface complexation was analyzed via X-ray absorption near edge structure (XANES) spectroscopy. X-ray diffraction analysis indicated bayerite, layered double hydroxides (LDH), and silicated LDH were formed as reaction products, thus creating new surface sites for potential K adsorption. The presence of Si increased K adsorption perhaps due to its role in the formation of LDH surface precipitates. When the differences between observed and theoretical surface area normalized K sorption densities were averaged, a 31% increase in K adsorption was observed in the presence of Si. XANES analysis indicated that the binding mechanism of K to Si is different than that of K to Al, perhaps due to the presence of inner-sphere complexation of K to Al-oxide. Samples reacted for one month versus one week yielded more intense XANES post-edge peaks which indicated that the K sorption complex changes over time. Overall, our findings provide novel insights into the mechanisms of K fixation in soil and has high implication in providing improved K fertilizer recommendation to growers.


Assuntos
Óxidos , Dióxido de Silício , Adsorção , Hidróxidos/química , Metais , Minerais/química , Potássio , Dióxido de Silício/química , Espectroscopia por Absorção de Raios X
11.
Respirol Case Rep ; 10(6): e0982, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35634249

RESUMO

Airway foreign bodies are common in children, and usually present as emergencies. However, they may sometimes present late, due to a number of reasons. Chronic lodgement of foreign bodies in trachea is rarer than that in bronchial tree. Flexible and rigid bronchoscopies have revolutionized the management of foreign bodies at large. Here, we report a successful bronchoscopic management of an unusual foreign body residing in the trachea of a patient for 15 years.

12.
Case Rep Surg ; 2022: 1974147, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35341077

RESUMO

Background: Ingestion of sharp foreign bodies is uncommon and often underreported. It can present with esophageal perforation which is a life-threatening complication requiring prompt diagnosis and management. Case Presentation. We report a case of accidental ingestion of a razor blade in a chronic alcoholic who presented with hematemesis after an esophageal perforation, the diagnosis of which was confirmed by radiology. Conclusion: Early recognition of esophageal perforation is crucial for early intervention. Proper history taking and radiological investigations are a key to reaching a diagnosis.

13.
Chem Biodivers ; 18(10): e2100300, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34375021

RESUMO

Trillium govanianum rhizomes are traditionally consumed as a raw powder and decoction for the treatment of health complications. Hence, the present study aimed to investigate whether aqueous and alcoholic extracts of T. govanianum rhizomes under hot and cold extraction conditions have similar or dissimilar chemical, nutrient, and antioxidant profiles. The total phenolics, flavonoids, carbohydrates, proteins, fats, and energy values were estimated in all the conditionally prepared samples. The total phenolics (21.23±1.4 mg GAE/g extract), flavonoids (70.57±3.24 mg RE/g extract) were found higher in hot ethanolic extract (TGHEt), while cold water extract (TGGC) showed higher nutrients including amino acids (10.545±0.219 mg/g) and nucleosides (1.803±0.018 mg/g). The nutrient energy value (2.60 and 2.49 Kcal/g extract) was higher in cold and hot ethanolic extracts. Further, TGHEt scavenged the DPPH. (IC50 ; 870±22 µg/mL) and ABTS.+ (IC50 ; 80±1.49 µg/mL) effectively and proved its highest antioxidant activity compared to other samples. In LC/MS/MS-based metabolite profiling, twenty-six metabolites (fatty acids, steroidal saponins, triterpene saponins, ecdysteroid hormones) were confirmed with mass fragmentation and literature, while one hundred nine metabolites were identified using the METLIN database. The principal component analysis showed clustering of hot condition extracts while cold extracts were differentially located in quadrants. The heatmaps exhibited the associations and differences between metabolite composition, solvents, and extraction conditions. The identified metabolites speculatively predicted the biosynthesis pathway of T. govanianum. Findings also illustrated that T. govanianum is a source of bioactive nutritional components and saponins. The current metabolite profiling of T. govanianum will help in its agricultural and biotechnological interventions for higher quality produce.


Assuntos
Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Trillium/química , Antioxidantes/química , Antioxidantes/metabolismo , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Picratos/antagonistas & inibidores , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Ácidos Sulfônicos/antagonistas & inibidores
14.
J Coll Physicians Surg Pak ; 30(5): 602-604, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34027880

RESUMO

Most pathology of the thymus gland warrant its surgical removal; and this requires significant expertise and adequate medical set-up. This study aimed to audit the results of thymectomies performed in a specialised tertiary level centre in a resource-poor country. The outcomes of open and minimally invasive video-assisted thoracoscopic surgery (VATS) thymectomies were also compared. Out of 58 patients operated at Department of Thoracic Surgery, Manmohan Cardiothoracic Vascular and Transplant Center, Maharajgunj, Kathmandu, Nepal between October 2012 and January 2019, 33 patients underwent open thymectomy and 25 had VATS thymectomy. We conducted a retrospective search to look at operative time, blood loss and length of postoperative hospitalisation. The open surgery group was followed for an average of 32 months, and the VATS cohort for 38 months. No significant differences were found in mean operative times and overall survival between groups. In selected cases, thymectomy via VATS is safer and comparable to open thymectomy in terms of operative safety and oncological completeness. Key Words: Thymus, VATS, Thymectomy, Outcome.


Assuntos
Timoma , Neoplasias do Timo , Humanos , Nepal , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida , Timectomia , Neoplasias do Timo/cirurgia , Resultado do Tratamento
15.
J Food Sci Technol ; 58(3): 1209-1215, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33678902

RESUMO

This study determined the anti-listerial activity of indigenous probiotics from traditional fermented foods of Western Himalaya against meat borne Listera monocytogens isolates from Himachal Pradesh. One hundred samples of meat and meat products like chicken (n = 25), chevon (goat meat, n = 20), fish (n = 20) and pork (n = 30) were collected and were analyzed for the presence of Listeria spp. by recommended culture and biochemical methods. L. monocytogens isolates were confirmed by PCR targeting the virulence gene hlyA (haemolysin A) and by16S rRNA sequencing. Anti-listerial activity of probiotic bacteria isolated from indigenous fermented foods of Himachal Pradesh was determined by well diffusion method using Lactobacillus rhamnosus GG (ATCC 53103) as the reference strain. Five percent of tested samples were found positive for L. monocytogens with incidence of 8.0% in chicken (2/25), 10.0% in fish (2/20) and 4.0% in chevon meat (1/25). None of the tested pork samples were found contaminated with L. monocytogenes. Among 11 indigenous probiotics used in this study, highest antagonistic activity was exhibited by Lactobacillus plantarum (ADF 10) and Enterococcus faecium (ADF1) which was equivalent to the reference strain.

16.
Mol Divers ; 25(1): 603-624, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32886304

RESUMO

Breast cancer is the most prominent, frequently diagnosed and leading cause of death among women. Estrogen is an agonist of estrogen receptor alpha (ER-α), expressed in mammary glands and is responsible for initiating many signalling pathways that lead to differentiation and development of breast tissue. Any mutations in these signalling pathways result in irregular growth of mammary tissue, leading to the development of tumour or cancer. All these observations attract the attention of researchers to antagonize ER-α receptor either by developing selective estrogen receptor modulators or by selective estrogen receptor degraders. Therefore, this article provides a brief overview of various factors that are responsible for provoking breast cancer in women and design strategies recently used by the various research groups across the world for antagonizing or demodulating ER-α.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Receptor alfa de Estrogênio/metabolismo , Terapia de Alvo Molecular , Receptor alfa de Estrogênio/antagonistas & inibidores , Feminino , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/uso terapêutico , Humanos , Modelos Moleculares
17.
J Synchrotron Radiat ; 26(Pt 6): 1967-1979, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31721742

RESUMO

Soils regulate the environmental impacts of trace elements, but direct measurements of reaction mechanisms in these complex, multi-component systems can be challenging. The objective of this work was to develop approaches for assessing effects of co-localized geochemical matrix elements on the accumulation and chemical speciation of arsenate applied to a soil matrix. Synchrotron X-ray fluorescence microprobe (µ-XRF) images collected across 100 µm × 100 µm and 10 µm × 10 µm regions of a naturally weathered soil sand-grain coating before and after treatment with As(V) solution showed strong positive partial correlations (r' = 0.77 and 0.64, respectively) between accumulated As and soil Fe, with weaker partial correlations (r' > 0.1) between As and Ca, and As and Zn in the larger image. Spatial and non-spatial regression models revealed a dominant contribution of Fe and minor contributions of Ca and Ti in predicting accumulated As, depending on the size of the sample area analyzed. Time-of-flight secondary ion mass spectrometry analysis of an area of the sand grain showed a significant correlation (r = 0.51) between Fe and Al, so effects of Fe versus Al (hydr)oxides on accumulated As could not be separated. Fitting results from 25 As K-edge microscale X-ray absorption near-edge structure (µ-XANES) spectra collected across a separate 10 µm × 10 µm region showed ∼60% variation in proportions of Fe(III) and Al(III)-bound As(V) standards, and fits to µ-XANES spectra collected across the 100 µm × 100 µm region were more variable. Consistent with insights from studies on model systems, the results obtained here indicate a dominance of Fe and possibly Al (hydr)oxides in controlling As(V) accumulation within microsites of the soil matrix analyzed, but the analyses inferred minor augmentation from co-localized Ti, Ca and possibly Zn.

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