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1.
Angew Chem Int Ed Engl ; : e202409610, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39087463

RESUMEN

Recent decades have seen a dramatic increase in the commercial use of biocatalysts, transitioning from energy-intensive traditional chemistries to more sustainable methods. Current enzyme engineering techniques, such as directed evolution, require the generation and testing of large mutant libraries to identify optimized variants. Unfortunately, conventional screening methods are unable to screen such large libraries in a robust and timely manner. Droplet-based microfluidic systems have emerged as a powerful high-throughput tool for library screening at kilohertz rates. Unfortunately, almost all reported systems are based on fluorescence detection, restricting their use to a limited number of enzyme types that naturally convert fluorogenic substrates or require the use of surrogate substrates. To expand the range of enzymes amenable to evolution using droplet-based microfluidic systems, we present an absorbance-activated droplet sorter that allows of droplet sorting at kilohertz rates without the need for optical monitoring of the microfluidic system. To demonstrate the utility of the sorter, we rapidly screen a 105-member aldehyde dehydrogenase library towards D-glyceraldehyde using a NADH mediated coupled assay that generates WST-1 formazan as the colorimetric product. We successfully identify a variant with a 51% improvement in catalytic efficiency and a significant increase in overall activity across a broad substrate spectrum.

4.
Anal Methods ; 16(30): 5280-5287, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39016030

RESUMEN

The stability-indicating approach for tavaborole quantification was developed and validated to establish a precise, linear, accurate, and robust HPLC method. The development section includes optimizing the detection wavelength, the mobile phase ratio, and the type of column used to achieve the best possible separation and sensitivity for analysis. The chromatographic conditions were established, considering peak symmetry, resolution, and retention time. The mobile phase composition, comprising a buffer: acetonitrile (75 : 25, %v/v), with an injection volume of 15 µL, showed suitable elution and recovery at 265 nm. A constant column oven temperature of 35 °C and a 1 mL min-1 flow rate were maintained. The pH of the buffer was changed to 3.0 by using orthophosphoric acid. Linearity was observed from 5 to 1000 ppm (r2 = 1.00000). The capacity (retention) factor (k) of 3.43 was observed, indicating significant interaction and good separation. Forced degradation (FD) or stress tests were performed for chemical and physical photolytic stress conditions, and the results observed were within the specified limits. The stability in the analytical solution was observed for up to 35 hours at 5 °C, confirming the stability of the solution. Validation of the developed HPLC method confirmed the system's suitability, precision, linearity, accuracy, FD, robustness, and results. All validation criteria for the technique were within acceptable limits.


Asunto(s)
Cromatografía de Fase Inversa , Cromatografía Líquida de Alta Presión/métodos , Cromatografía de Fase Inversa/métodos , Reproducibilidad de los Resultados , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Compuestos Bicíclicos Heterocíclicos con Puentes/análisis , Estabilidad de Medicamentos , Límite de Detección
5.
Proc Natl Acad Sci U S A ; 121(31): e2403585121, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39042685

RESUMEN

Nature is home to a variety of microorganisms that create materials under environmentally friendly conditions. While this offers an attractive approach for sustainable manufacturing, the production of materials by native microorganisms is usually slow and synthetic biology tools to engineer faster microorganisms are only available when prior knowledge of genotype-phenotype links is available. Here, we utilize a high-throughput directed evolution platform to enhance the fitness of whole microorganisms under selection pressure and identify genetic pathways to enhance the material production capabilities of native species. Using Komagataeibacter sucrofermentans as a model cellulose-producing microorganism, we show that our droplet-based microfluidic platform enables the directed evolution of these bacteria toward a small number of cellulose overproducers from an initial pool of 40,000 random mutants. Sequencing of the evolved strains reveals an unexpected link between the cellulose-forming ability of the bacteria and a gene encoding a protease complex responsible for protein turnover in the cell. The ability to enhance the fitness of microorganisms toward a specific phenotype and to unravel genotype-phenotype links makes this high-throughput directed evolution platform a promising tool for the development of new strains for the sustainable manufacturing of materials.


Asunto(s)
Celulosa , Evolución Molecular Dirigida , Celulosa/metabolismo , Celulosa/biosíntesis , Evolución Molecular Dirigida/métodos , Acetobacteraceae/metabolismo , Acetobacteraceae/genética , Fenotipo , Mutación
7.
Small ; : e2400775, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38829024

RESUMEN

Graphene, a 2D carbon material, possesses extraordinary mechanical, electrical, and thermal properties, making it highly attractive for various biological applications such as biosensing, biotherapeutics, and tissue engineering. However, the tendency of graphene sheets to aggregate and restack hinders its dispersion in water, limiting these applications. Peptides, with their defined amino acid sequences and versatile functionalities, are compelling molecules with which to modify graphene-aromatic amino acids can strengthen interactions through π-stacking and charged groups can be chosen to make the sheets dispersible and stable in water. Here, a facile and green method for covalently functionalizing and dispersing graphene using amphiphilic tripeptides, facilitated by a tyrosine phenol side chain, through an aqueous enzymatic oxidation process is demonstrated. The presence of a second aromatic side chain group enhances this interaction through non-covalent support via π-π stacking with the graphene surface. Futhermore, the addition of charged moieties originating from either ionizable amino acids or terminal groups facilitates profound interactions with water, resulting in the dispersion of the newly functionalized graphene in aqueous solutions. This biofunctionalization method resulted in ≈56% peptide loading on the graphene surface, leading to graphene dispersions that remain stable for months in aqueous solutions outperforming currently used surfactants.

8.
J Surg Orthop Adv ; 33(1): 1-4, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38815069

RESUMEN

Surgical scissors form an essential part of both basic and specialty surgical sets. Their prime function is to cut tissues. They are also used for blunt dissection/development of tissue planes and piercing tissues. A wide variety of scissors are available for use in practice. This review article briefly describes common surgical scissors in orthopaedic use. The basic construct, biomechanics, types, their identification, specific uses, and care aspects are also discussed. A surgeon should be aware of the different types of scissors, their biomechanical features, and specific uses, as they are an important tool in his/her armamentarium. (Journal of Surgical Orthopaedic Advances 33(1):001-004, 2024).


Asunto(s)
Instrumentos Quirúrgicos , Humanos , Procedimientos Ortopédicos/instrumentación , Diseño de Equipo , Fenómenos Biomecánicos
9.
Gels ; 10(5)2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38786260

RESUMEN

The present study delves into the evolution of traditional Ayurvedic oil preparations through innovative strategies to develop advanced gel formulations, aiming at amplifying their therapeutic efficacy. Ayurvedic oils have a rich historical context in healing practices, yet their conversion into contemporary gel-based formulations represents a revolutionary approach to augment their medicinal potential. The primary objective of this transformation is to leverage scientific advancements and modern pharmaceutical techniques to enhance the application, absorption, and overall therapeutic impact of these traditional remedies. By encapsulating the essential constituents of Ayurvedic oils within gel matrices, these novel strategies endeavor to improve their stability, bioavailability, and targeted delivery mechanisms. This review highlights the fusion of traditional Ayurvedic wisdom with cutting-edge pharmaceutical technology, paving the way for more effective and accessible utilization of these revered remedies in modern healthcare.

10.
Natl J Maxillofac Surg ; 15(1): 93-99, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38690233

RESUMEN

Background: The aim of this study is to evaluate the location and radio morphometric features of the posterior superior alveolar artery (PSAA) in patients undergoing rehabilitation of posterior maxilla and other sinus augmentation surgical procedures by cone-beam computed tomography (CBCT). Materials and Methods: A total of 816 CBCT scans were included. Various radio morphometric measurements were done to assess the PSAA location, diameter, and distances to the sinus floor and alveolar crest. Results: The PSAA was mostly intraosseous in the maximum in the age group 31-51 years (56%), in males (53.4%), and in dentate patients (57.4%). The artery tends to be wider in older patients. Distances to the sinus floor or the alveolar crest tend to be shorter in women. Conclusions: This study suggests that CBCT is a valuable pre-surgical tool and the evaluation of the PSAA on CBCT images could reduce the likelihood of excess bleeding during surgery in the maxillary posterior region.

11.
Fitoterapia ; 175: 105978, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38685508

RESUMEN

BACKGROUND: Semecarpus anacardium Linn. (SCA) fruits are found in India's sub-Himalayan, tropical, and central regions and have been utilized for centuries in traditional Indian medicine to treat various ailments. In recent times, a growing body of research has emerged indicating that the extracts and active components found in SCA fruits possess qualities that can potentially inhibit the development of cancer and inflammatory markers. PURPOSE: This study aims to provide a comprehensive review of the existing literature on the pharmacological mechanisms underlying the effects of extracts and phytochemicals of SCA fruits in cellular, animal models, and clinical trials of cancer and inflammatory diseases. METHODS: A comprehensive literature search was conducted utilizing several databases, including PubMed, Scopus, Google Scholar, preprint platforms, and the Cochrane Database of Systematic Reviews using the keywords "Semecarpus anacardium", "Anti-inflammatory," and "cancer". The collection of articles started with establishing the database and continued until April 2024. RESULTS: Out of 1130 retrieved database records, 316 pertained to systematic reviews. The remaining 814 records focused on examining the anticancer and anti-inflammatory properties of SCA fruits. In the course of these investigations, the four primary cancer types linked to SCA fruits are identified as lung cancer, hepatocellular carcinoma, breast cancer, and blood cancer. CONCLUSION: The findings will provide more support for investigating SCA fruits in cancer treatment and will furnish thorough reference data and recommendations for future studies on this botanical medication.


Asunto(s)
Frutas , Fitoquímicos , Extractos Vegetales , Semecarpus , Animales , Humanos , Antiinflamatorios/farmacología , Antineoplásicos Fitogénicos/farmacología , Frutas/química , India , Inflamación/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Semecarpus/química
12.
Curr Opin Biotechnol ; 87: 103097, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38430713

RESUMEN

Enzymes are widely used as catalysts in the chemical and pharmaceutical industries. While successful in many situations, they must usually be adapted to operate efficiently under nonnatural conditions. Enzyme engineering allows the creation of novel enzymes that are stable at elevated temperatures or have higher activities and selectivities. Current enzyme engineering techniques require the production and testing of enzyme variant libraries to identify members with desired attributes. Unfortunately, traditional screening methods cannot screen such large mutagenesis libraries in a robust and timely manner. Droplet-based microfluidic systems can produce, process, and sort picoliter droplets at kilohertz rates and have emerged as powerful tools for library screening and thus enzyme engineering. We describe how droplet-based microfluidics has been used to advance directed evolution.


Asunto(s)
Evolución Molecular Dirigida , Microfluídica , Evolución Molecular Dirigida/métodos , Microfluídica/métodos , Enzimas/metabolismo , Enzimas/genética , Enzimas/química , Ingeniería de Proteínas/métodos
15.
Mol Cell Oncol ; 11(1): 2328873, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38487372

RESUMEN

Cisplatin is the commonly used chemotherapeutic drug in treatment of various cancers. However, development of resistance towards cisplatin results in tumor recurrence. Here, we aim to understand the mechanisms of action of cisplatin and emergence of resistance to cisplatin using mass spectrometry-based proteomic approach. A panel of head and neck squamous cell carcinoma (HNSCC) cell lines were treated with cisplatin at respective IC50 for 24 h and label-free mass spectrometry analysis was carried out. Proteomic analysis of A253, FaDu, Det562 and CAL27 cell lines upon cisplatin treatment resulted in the identification of 5,060, 4,816, 4,537 and 4,142 proteins, respectively. Bioinformatics analysis of differentially regulated proteins revealed proteins implicated in DNA damage bypass pathway, translation and mRNA splicing to be enriched. Further, proteins associated with cisplatin resistance exhibited alterations following short-term cisplatin exposure. Among these, class III tubullin protein (TUBB3) was found to be upregulated in cisplatin-treated cells compared to untreated cells. Western blot analysis confirmed the elevated expression of TUBB3 in cells treated with cisplatin for 24 h, and also in cisplatin resistant HNSCC cell lines. This study delineates the early signaling events that enable HNSCC cells to counteract the cytotoxic effects of cisplatin and facilitate the development of resistance.

16.
Chemphyschem ; 25(10): e202300993, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38369607

RESUMEN

We investigated electrochemical nitrogen reduction reaction (eNRR) on MXenes consisting of the vacancy defects in the functional layer using density functional theory calculations. We considered Mo2C, W2C, Mo2N, and W2N MXenes with F, N, and O functionalization and investigated distal and alternative associative pathways. We analyzed these MXenes for eNRR based on N2 adsorption energy, NH3 desorption energy, NRR selectivity, and electrochemical limiting potential. While we find that most of the considered MXenes surfaces are more favorable for eNRR compared to hydrogen evolution, these surfaces also have strong NH3 binding (>-1.0 eV) and thus will be covered with NH3 during operating conditions. Amongst all considered MXenes, only W2NF2 is found to have a low NH3 desorption energy along with low eNRR overpotential and selectivity towards eNRR. The obtained eNRR overpotential and NH3 desorption energy on W2NF2 are superior to those reported for pristine W2N3 as well as functionalized MXenes.

17.
BMJ Case Rep ; 17(2)2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38367993

RESUMEN

Peripherally inserted central catheter (PICC) insertion is a routine procedure in the neonatal intensive care unit required for prolonged intravenous fluid, nutrition and medication support. Neonatal cardiac tamponade is a serious and rare complication of PICC line insertion. Early detection by point of care ultrasound (POCUS) and management by pericardiocentesis improves the chances of survival. Regular simulation-based training sessions on a mannequin, along with knowledge of POCUS, can assist neonatologists and paediatricians for a quick and appropriate response in this emergency condition.


Asunto(s)
Taponamiento Cardíaco , Cateterismo Venoso Central , Humanos , Recién Nacido , Taponamiento Cardíaco/diagnóstico por imagen , Taponamiento Cardíaco/etiología , Taponamiento Cardíaco/terapia , Cateterismo Venoso Central/efectos adversos , Cateterismo Venoso Central/métodos , Pericardiocentesis , Sistemas de Atención de Punto , Ultrasonografía
18.
Int Orthop ; 48(6): 1411-1417, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38351364

RESUMEN

PURPOSE: The aim of this study was to appraise various factors influencing the correction rate in temporary hemiepiphysiodesis (THE) around the knee joint. Specifically, the study analysed the relationship of correction rate with age, gender, aetiology, type and location of deformity. METHODS: The retrospective study included children who underwent THE for a coronal plane deformity (genu valgus or varum) around the knee joint (distal femur or proximal tibia) over a ten year period (2010-2020). The primary outcome of interest was the correction rate of the deformity. RESULTS: Thirty-three children (27 females and 6 males) with a mean age of 8.1 years involving 86 plates were included in the study. The mean correction achieved was 12.2° over a treatment period of 13.3 months. Subgroup analysis showed significant differences between the type (varus (0.8° per month), valgus (1.1° per month)) and the location of deformity femur (1.2° per month) and tibia (0.7° per month)]. On multivariate analysis, the location and the duration of treatment showed significant associations with the correction rate. CONCLUSION: The correction of coronal deformities following temporary hemiepiphysiodesis is influenced by several factors. Valgus, femoral and deformities in younger children correct at a faster rate. Location of deformity and duration of treatment emerged as potential factors affecting the correction rate.


Asunto(s)
Placas Óseas , Articulación de la Rodilla , Humanos , Femenino , Masculino , Estudios Retrospectivos , Niño , Articulación de la Rodilla/cirugía , Articulación de la Rodilla/anomalías , Articulación de la Rodilla/fisiopatología , Tibia/cirugía , Tibia/anomalías , Fémur/cirugía , Fémur/anomalías , Preescolar , Análisis Multivariante , Resultado del Tratamiento , Genu Varum/cirugía , Adolescente , Epífisis/cirugía
19.
Langenbecks Arch Surg ; 409(1): 73, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38393412

RESUMEN

The main purpose of this study is to explore the outcomes of patients found to have gallbladder cancer during investigation and diagnosis of acute cholecystitis. The incidence of primary gallbladder cancer co-existing in acute cholecystitis is not well defined in the literature, with anecdotal reports suggesting that they experience worse outcomes than patients with gallbladder cancer found incidentally. METHODS: A retrospective review of all patients with gallbladder cancer managed at the Canberra Health Service between 1998 and May 2022 were identified and reviewed. RESULTS: A total of 65 patients were diagnosed with primary gallbladder cancer during the study period with a mean age of 70.4 years (SD 11.4, range 59-81.8 years) and a female preponderance (74% versus 26%) with a ratio of 2.8. Twenty (31%) patients presented with acute calculus cholecystitis and were found to have a primary gallbladder cancer. This group of patients were older and predominantly female, but the difference was not statistically significant. The overall 5-year survival in the cohort was 20% (stage 1 63%, stage 2 23%, stage 3 16%, and stage 4 0%). There was no statistically significant difference in survival between those who presented with acute cholecystitis vs other presentations. CONCLUSIONS: A third of the patients with gallbladder cancer presented with acute cholecystitis. There was no statistically significant difference in survival in those with bile spillage during cholecystectomy as well those presenting with acute cholecystitis.


Asunto(s)
Colecistitis Aguda , Neoplasias de la Vesícula Biliar , Humanos , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Masculino , Neoplasias de la Vesícula Biliar/complicaciones , Neoplasias de la Vesícula Biliar/cirugía , Neoplasias de la Vesícula Biliar/diagnóstico , Colecistitis Aguda/complicaciones , Colecistitis Aguda/diagnóstico , Colecistitis Aguda/cirugía , Colecistectomía , Estudios Retrospectivos
20.
Anticancer Agents Med Chem ; 24(8): 590-626, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38288815

RESUMEN

New drugs being established in the market every year produce specified structures for selective biological targeting. With medicinal insights into molecular recognition, these begot molecules open new rooms for designing potential new drug molecules. In this review, we report the compilation and analysis of a total of 56 drugs including 33 organic small molecules (Mobocertinib, Infigratinib, Sotorasib, Trilaciclib, Umbralisib, Tepotinib, Relugolix, Pralsetinib, Decitabine, Ripretinib, Selpercatinib, Capmatinib, Pemigatinib, Tucatinib, Selumetinib, Tazemetostat, Avapritinib, Zanubrutinib, Entrectinib, Pexidartinib, Darolutamide, Selinexor, Alpelisib, Erdafitinib, Gilteritinib, Larotrectinib, Glasdegib, Lorlatinib, Talazoparib, Dacomitinib, Duvelisib, Ivosidenib, Apalutamide), 6 metal complexes (Edotreotide Gallium Ga-68, fluoroestradiol F-18, Cu 64 dotatate, Gallium 68 PSMA-11, Piflufolastat F-18, 177Lu (lutetium)), 16 macromolecules as monoclonal antibody conjugates (Brentuximabvedotin, Amivantamab-vmjw, Loncastuximabtesirine, Dostarlimab, Margetuximab, Naxitamab, Belantamabmafodotin, Tafasitamab, Inebilizumab, SacituzumabGovitecan, Isatuximab, Trastuzumab, Enfortumabvedotin, Polatuzumab, Cemiplimab, Mogamulizumab) and 1 peptide enzyme (Erwiniachrysanthemi-derived asparaginase) approved by the U.S. FDA between 2018 to 2021. These drugs act as anticancer agents against various cancer types, especially non-small cell lung, lymphoma, breast, prostate, multiple myeloma, neuroendocrine tumor, cervical, bladder, cholangiocarcinoma, myeloid leukemia, gastrointestinal, neuroblastoma, thyroid, epithelioid and cutaneous squamous cell carcinoma. The review comprises the key structural features, approval times, target selectivity, mechanisms of action, therapeutic indication, formulations, and possible synthetic approaches of these approved drugs. These crucial details will benefit the scientific community for futuristic new developments in this arena.


Asunto(s)
Antineoplásicos , United States Food and Drug Administration , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Estados Unidos , Aprobación de Drogas , Neoplasias/tratamiento farmacológico , Estructura Molecular
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