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1.
Emerg Infect Dis ; 30(2): 391-394, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38270179

RESUMEN

We report an outbreak of COVID-19 in a beaver farm in Mongolia in 2021. Genomic characterization revealed a unique combination of mutations in the SARS-CoV-2 of the infected beavers. Based on these findings, increased surveillance of farmed beavers should be encouraged.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Mongolia/epidemiología , SARS-CoV-2/genética , Granjas , Brotes de Enfermedades
2.
Artículo en Inglés | MEDLINE | ID: mdl-38684469

RESUMEN

Outcome prediction for live-donor kidney transplantation improves clinical and patient decisions and donor selection. However, the concurrently used models are of limited discriminative or calibration power and there is a critical need to improve the selection process. We aimed to assess the value of various artificial intelligence (AI) algorithms to improve the risk stratification index. We evaluated pre-transplant variables among 66 914 live-donor kidney transplants (performed between 01/12/2007-01/06/2021) from the United Network of Organ Sharing database, randomized into training (80%) and test (20%) sets. The primary outcome measure was death-censored graft survival. We tested four machine learning models for discrimination (time-dependent concordance index, CTD, and area under the ROC curve) and calibration (integrated Brier score, IBS). We used decision curve analysis to assess the potential clinical utility. Among the models, the deep Cox mixture model showed the best discriminative performance (AUC = 0.70, 0.68, and 0.68 at 5, 10, and 13 years post-transplant, respectively). CTD reached 0.70, 0.67, and 0.66 at 5, 10, and 13 years post-transplant. The IBS score was 0.09, indicating good calibration. In comparison, applying the Living Kidney Donor Profile Index (LKDPI) on the same cohort produced a CTD of 0.56 and an AUC of 0.55-0.58 only. Decision curve analysis showed an additional net benefit compared to the LKDPI, 'Treat all' and 'Treat None' approaches. Our AI-based deep Cox mixture model, termed Live-Donor Kidney Transplant Outcome Prediction outperforms existing prediction models, including the LKDPI, with the potential to improve decisions for optimum live donor selection by ranking potential transplant pairs based on graft survival. This model could be adopted to improve the outcomes of paired exchange programs.

3.
Molecules ; 28(14)2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37513240

RESUMEN

Medicinal plant extracts are a promising source of bioactive minor contents. The present study aimed to evaluate the distinguished volatile content of Algerian Cymbopogon citratus (DC.) Stapf before and after the microfluidization process and their related antimicrobial and anti-mycotoxigenic impacts and changes. The GC-MS apparatus was utilized for a comparative examination of Algerian lemongrass essential oil (LGEO) with its microfluidization nanoemulsion (MF-LGEO) volatile content. The MF-LGEO was characterized using Zetasizer and an electron microscope. Cytotoxicity, antibacterial, and antifungal activities were determined for the LGEO and MF-LGEO. The result reflected changes in the content of volatiles for the MF-LGEO. The microfluidizing process enhanced the presence of compounds known for their exceptional antifungal and antibacterial properties in MF-LGEO, namely, neral, geranial, and carvacrol. However, certain terpenes, such as camphor and citronellal, were absent, while decanal, not found in the raw LGEO, was detected. The droplet diameter was 20.76 ± 0.36 nm, and the polydispersity index (PDI) was 0.179 ± 0.03. In cytotoxicity studies, LGEO showed higher activity against the HepG2 cell line than MF-LGEO. Antibacterial LGEO activity against Gram-positive bacteria recorded an inhibitory zone from 41.82 ± 2.84 mm to 58.74 ± 2.64 mm, while the zone ranged from 12.71 ± 1.38 mm to 16.54 ± 1.42 mm for Gram-negative bacteria. Antibacterial activity was enhanced to be up to 71.43 ± 2.54 nm and 31.54 ± 1.01 nm for MF-LGEO impact against Gram-positive and Gram-negative pathogens. The antifungal effect was considerable, particularly against Fusarium fungi. It reached 17.56 ± 1.01 mm and 13.04 ± 1.37 mm for LGEO and MF-LGEO application of a well-diffusion assay, respectively. The MF-LGEO was more promising in reducing mycotoxin production in simulated fungal growth media due to the changes linked to essential compounds content. The reduction ratio was 54.3% and 74.57% for total aflatoxins (AFs) and ochratoxin A (OCA) contents, respectively. These results reflect the microfluidizing improvement impact regarding the LGEO antibacterial, antifungal and anti-mycotoxigenic properties.


Asunto(s)
Antiinfecciosos , Cymbopogon , Aceites Volátiles , Antifúngicos/farmacología , Antiinfecciosos/farmacología , Aceites Volátiles/farmacología , Antibacterianos/farmacología
4.
Am J Nephrol ; 52(4): 279-291, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33887727

RESUMEN

INTRODUCTION: The additive benefit of interleukin-2 receptor antagonist (IL2-RA) induction in standard-risk kidney transplant recipients, while maintained on tacrolimus-based immunosuppressive therapy, is uncertain. METHODS: We divided the studies included in this meta-analysis into 2 groups: group A (included studies that used same dose of tacrolimus in both arms of each study) and group B (included studies that compared patients who received induction therapy and low-dose tacrolimus vs. those who received no-induction therapy and high dose of tacrolimus). RESULTS: In group A, 11 studies were included (n = 2,886). IL2-RA induction therapy was not associated with significant differences in comparison to no-induction therapy in terms of acute rejection rates at 6 months post-transplant (risk ratio = 1.12 and 95% confidence interval [CI] range: 0.94-1.35) or graft survival at 1 year post-transplant (risk ratio = 0.78 and 95% CI range: 0.45-1.36). In group B, 2 studies were included (n = 669). There was no difference between both arms in terms of acute rejection rates (risk ratio = 0.62, with 95% CI range: 0.33-1.14) or graft survival (risk ratio = 1 and 95% CI range: 0.57-1.74). CONCLUSION: IL2-RA induction therapy does not improve outcomes in patients maintained on tacrolimus-based immunotherapy in standard-risk population.


Asunto(s)
Inmunosupresores/uso terapéutico , Trasplante de Riñón , Receptores de Interleucina-2/antagonistas & inhibidores , Tacrolimus/uso terapéutico , Humanos , Quimioterapia de Inducción , Quimioterapia de Mantención , Medición de Riesgo , Resultado del Tratamiento
5.
Molecules ; 26(14)2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34299420

RESUMEN

A comparative study of volatile constituents, antioxidant activity, and molecular docking was conducted between essential oils from Mentha longifolia L., Mentha spicata L., and Origanum majorana L., widely cultivated in Madinah. The investigation of volatile oils extracted by hydrodistillation was performed using Gas Chromatography-Mass Spectrometry (GC-MS). A total number of 29, 42, and 29 components were identified in M. longifolia, M. spicata, and O. majorana representing, respectively, 95.91, 94.62, and 98.42, of the total oils. Pulegone (38.42%), 1,8-cineole (15.60%), menthone (13.20%), and isopulegone (9.81%) were the dominant compounds in M. longifolia oil; carvone (35.14%), limonene (27.11%), germacrene D (4.73%), and ß-caryophyllene (3.02%) were dominant in M. spicata oil; terpin-4-ol (42.47%), trans-sabinene hydrate (8.52%), γ-terpinene (7.90%), α-terpineol (7.38%), linalool (6.35%), α-terpinene (5.42%), and cis-sabinene hydrate (3.14%) were dominant in O. majorana oil. The antioxidant activity, assessed using DPPH free radical-scavenging and ABTS assays, was found to be the highest in O. majorana volatile oil, followed by M. spicata and M. longifolia, which is consistent with the differences in total phenolic content and volatile constituents identified in investigated oils. In the same context, molecular docking of the main identified volatiles on NADPH oxidase showed a higher binding affinity for cis-verbenyl acetate, followed by ß-elemene and linalool, compared to the control (dextromethorphan). These results prove significant antioxidant abilities of the investigated oils, which may be considered for further analyses concerning the control of oxidative stress, as well as for their use as possible antioxidant agents in the pharmaceutical industry.


Asunto(s)
Antioxidantes/farmacología , Mentha/química , NADPH Oxidasas/metabolismo , Aceites Volátiles/farmacología , Origanum/química , Compuestos Orgánicos Volátiles/farmacología , Antioxidantes/análisis , Simulación del Acoplamiento Molecular , Aceites Volátiles/análisis , Arabia Saudita , Compuestos Orgánicos Volátiles/análisis
6.
Internist (Berl) ; 62(12): 1338-1342, 2021 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-34338841

RESUMEN

This article reports two cases of patients with coronavirus disease 2019 (COVID-19) in which occlusion of large cerebral arteries occurred. These occurred in a female patient in the early stage of COVID-19 and in the second case in the late stage. One female patient could be successfully treated with i.v. thrombolysis and mechanical thrombectomy. Coagulopathy in the course of COVID-19 can result in severe stroke with poor outcome even in younger patients. With respect to the etiology of arterial occlusions (COVID-19-induced hypercoagulopathy, cardiomyopathy, vasculitis) there is a necessity for further research.


Asunto(s)
Isquemia Encefálica , COVID-19 , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Femenino , Humanos , SARS-CoV-2 , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/terapia , Trombectomía , Terapia Trombolítica , Resultado del Tratamiento
7.
Am J Nephrol ; 51(5): 366-372, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32268334

RESUMEN

BACKGROUND: This study aims to assess outcomes of interleukin-2 (IL-2) receptor blocker induction therapy on allograft and patients' outcomes in standard risk recipients in the tacrolimus era, analysing data form the British Renal Transplant Registry. METHODS: The study population involved all standard-risk renal transplant patients from 2000 till 2015 who were registered in the UK transplant registry and followed up till May 2018. Standard risk transplants were defined as patients with <2DR mismatch, calculated reaction frequency <20%, live donors or donors after brain death and patients with no previous renal transplantation transplant. We used inverse probability weights to adjust different covariates between the groups. Cox regression analysis for adjusted data and treatment effects model were used to assess outcomes. RESULTS: In all, 3,597 renal transplant patients were included in the study. Two groups were identified; induction group (n = 2,858) which included patients who received IL-2 receptor blocker induction therapy and the no-induction group (n = 739). There was no significant difference between both groups in terms of estimated glomerular filtration rate (eGFR) rate at 1-year post-transplant (correlation co-efficient = 1.224, 95% CI ranges from -0.347 to 2.796). Average eGFR was 59.922 mL/min/1.73 m2 in the induction group (SD 29.171) and 64.557 mL/min/1.73 m2 in the no-induction groups (SD 46.763). There was no significant difference between both groups regarding graft survival at 5 years post-transplant (hazard ratio [HR] 0.944, 95% CI ranges from 0.599 to 1.485, p = 0.804), patient survival at 5 years post-transplant (HR 0.809, 95% CI ranges from 0.477 to1.372, p = 0.433). CONCLUSION: In the standard risk renal transplant population, the IL2 receptor blocker induction regimen does not affect eGFR at 1 year or renal and graft outcomes at 5 years.


Asunto(s)
Rechazo de Injerto/epidemiología , Inmunosupresores/administración & dosificación , Fallo Renal Crónico/cirugía , Trasplante de Riñón/efectos adversos , Receptores de Interleucina-2/antagonistas & inhibidores , Adulto , Quimioterapia Combinada/métodos , Quimioterapia Combinada/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular/efectos de los fármacos , Tasa de Filtración Glomerular/inmunología , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Supervivencia de Injerto/inmunología , Humanos , Quimioterapia de Inducción/métodos , Fallo Renal Crónico/mortalidad , Masculino , Persona de Mediana Edad , Sistema de Registros/estadística & datos numéricos , Estudios Retrospectivos , Análisis de Supervivencia , Tacrolimus/administración & dosificación , Trasplante Homólogo/efectos adversos , Resultado del Tratamiento , Reino Unido/epidemiología
8.
Ren Fail ; 42(1): 489-494, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32423337

RESUMEN

Introduction: The aim of our study is to explore the relationship of rabbit anti-thymocyte globulin (R-ATG) on development of post-transplant lymphoproliferative disease (PTLD) and its aggressive forms (monomorphic PTLD and Hodgkin lymphoma) in renal transplant recipients.Methodology: All patients diagnosed with PTLD post-renal transplant in the United States' Organ Procurement and Transplantation Network from 2003 till 2013 and followed up till 2017 were retrospectively reviewed. Multi-variable logistic regression analysis assessed association of R-ATG to development of PTLD and its aggressive form.Results: Risk of developing PTLD post renal transplant is 1.35%. In comparison to interleukin-2 blocker induction therapy, R-ATG is associated with increased risk of development of PTLD (Odds Ratio = 1.48, confidence interval ranges from 1.04 to 2.11, p = .02) and is associated with higher risk of development of aggressive PTLD (Odds Ratio = 1.83, confidence interval ranges from 1.001 to 3.34, p = .04).Conclusion: We conclude that R-ATG induction is associated with a higher risk of PTLD and its aggressive form (monomorphic PTLD and Hodgkin lymphoma). Careful monitoring for development of PTLD in renal transplant recipients receiving R-ATG induction therapy is advised.


Asunto(s)
Suero Antilinfocítico/inmunología , Trasplante de Riñón , Trastornos Linfoproliferativos/diagnóstico , Animales , Humanos , Trastornos Linfoproliferativos/inmunología , Conejos , Índice de Severidad de la Enfermedad
9.
Molecules ; 25(20)2020 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-33081286

RESUMEN

The nanoencapsulation of essential oils enhances their applicability in several areas, such as pharmaceuticals and food biopreservation. This study focuses on the encapsulation of Saccocalyx satureioides Coss. et Durieu essential oil into nanoemulsions by high-pressure homogenization (HPH) and its effect on the volatile constituents and the antioxidant and anticancer activities of the essential oil. The analysis of hydrodistilled (HD) S. satureioides essential oil using gas chromatography-mass spectrometry revealed a total of 28 constituents, representing 99.80%, while only 13 constituents were identified in nanoemulsions, representing 98.65% of the total volatile material. The use of HPH led to qualitative and quantitative differences between the volatile profiles of the HD and the nanoemulsion of S. satureioides essential oil. Whereas borneol, α-terpineol, and thymol were the predominant constituents in the HD oil, carvacrol, thymol, and γ-terpinene were the major constituents in the nanoemulsion. The antioxidant activity of the S. satureioides essential oil nanoemulsion displayed was lower as compared to that of HD oil using DPPH free radical-scavenging, CUPRAC, and ABTS assays. This is consistent with the differences in total flavonoid, total phenolic, and volatiles detected in both HD oil and its nanoemulsion. Meanwhile, the cytotoxicity on liver cancer cells (Hep-G2) was stronger using nanoemulsions (106 µg/mL) than using HD oil (274.8 µg/mL).


Asunto(s)
Antineoplásicos/farmacología , Antioxidantes/farmacología , Lamiaceae/química , Compuestos Orgánicos Volátiles/farmacología , Antibacterianos/química , Antineoplásicos/química , Antioxidantes/química , Cromatografía de Gases y Espectrometría de Masas , Humanos , Nanotecnología , Aceites Volátiles/química , Aceites Volátiles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Aceites de Plantas/química , Aceites de Plantas/farmacología , Compuestos Orgánicos Volátiles/química
10.
Nephrol Dial Transplant ; 34(11): 1950-1960, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30508114

RESUMEN

The presence of pre-formed donor-specific antibodies (DSAs) in kidney transplantation is associated with worse overall outcomes compared with DSA-negative transplantation. A positive complement-dependant cytotoxic crossmatch presents a high immunological risk, while a negative flow cytometry crossmatch is at the lower end of the risk spectrum. Yet, the presence of low-level DSA detected by Luminex alone, that is, positive Luminex and negative flow (PLNF) cytometry crossmatch lacks robust scientific exploration. In this systematic review and pooled analysis, we investigate the glomerular filtration rate, acute rejection (AR), graft survival and patient survival of PLNF transplants compared with DSA-negative transplants. Our analysis identified seven retrospective studies consisting of 429 PLNF transplants and 10 677 DSA-negative transplants. Pooled analysis identified no significant difference in the incidence of AR at 1 year [relative risk (RR) = 1.35, 95% confidence interval (CI) 0.90-2.02, Z = 1.46, P = 0.14, I2 = 0%], graft failure at 1 year (RR = 1.66, 95% CI 0.94-2.94, Z = 1.75, P = 0.08, I2 = 23%), graft failure at 5 years (RR = 1.29, 95% CI 0.90-1.87, Z = 1.38, P = 0.17, I2 = 0%), patient mortality at 1 year (RR = 0.89, 95% CI 0.31-2.56, Z = 0.22, P = 0.82, I2 = 0%) and patient mortality at 5 years (RR = 1.76, 95% CI 0.48-6.48, Z = 0.85, P = 0.39, I2 = 61%). Pooled analysis of graft function was not possible due to insufficient data. Current evidence suggests that low-level DSA detected by Luminex alone does not pose significant risk at least in the short-medium term. Considering the shortage of kidney transplants and the ever-increasing waiting time, the avoidance of PLNF transplants may be unwarranted especially in patients who have been enlisted for a long time.


Asunto(s)
Pruebas Inmunológicas de Citotoxicidad/métodos , Citometría de Flujo/métodos , Rechazo de Injerto/diagnóstico , Supervivencia de Injerto/inmunología , Isoanticuerpos/inmunología , Trasplante de Riñón/métodos , Tasa de Filtración Glomerular , Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Prueba de Histocompatibilidad , Humanos , Isoanticuerpos/sangre , Estudios Retrospectivos , Donantes de Tejidos
14.
Amino Acids ; 46(9): 2241-57, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24938763

RESUMEN

Whereas an abundance of literature is available on the occurrence of common proteinogenic amino acids (AAs) in edible fruits of the date palm (Phoenix dactylifera L.), recent reports on non-proteinogenic (non-coded) AAs and amino components are scarce. With emphasis on these components we have analyzed total hydrolysates of twelve cultivars of date fruits using automated ion-exchange chromatography, HPLC employing a fluorescent aminoquinolyl label, and GC-MS of total hydrolysates using the chiral stationary phases Chirasil(®)-L-Val and Lipodex(®) E. Besides common proteinogenic AAs, relatively large amounts of the following non-proteinogenic amino acids were detected: (2S,5R)-5-hydroxypipecolic acid (1.4-4.0 g/kg dry matter, DM), 1-aminocyclopropane-1-carboxylic acid (1.3-2.6 g/kg DM), γ-amino-n-butyric acid (0.5-1.2 g/kg DM), (2S,4R)-4-hydroxyproline (130-230 mg/kg DM), L-pipecolic acid (40-140 mg/kg DM), and 2-aminoethanol (40-160 mg/kg DM) as well as low or trace amounts (<70 mg/kg DM) of L-ornithine, 5-hydroxylysine, ß-alanine, and in some samples (<20 mg/kg DM) of (S)-ß-aminoisobutyric acid and (<10 mg/kg DM) L-allo-isoleucine. In one date fruit, traces of α-aminoadipic acid could be determined. Enantiomeric analysis of 6 M DCl/D2O hydrolysates of AAs using chiral capillary gas chromatography-mass spectrometry revealed the presence of very low amounts of D-Ala, D-Asp, D-Glu, D-Ser and D-Phe (1.2-0.4%, relative to the corresponding L-enantiomers), besides traces (0.2-1%) of other D-AAs. The possible relevance of non-proteinogenic amino acids in date fruits is briefly addressed.


Asunto(s)
Aminoácidos/análisis , Frutas/química , Phoeniceae/química , Proteínas de Plantas/análisis , Aminoácidos/química , Proteínas de Plantas/química , Arabia Saudita , Estereoisomerismo
15.
Arch Pharm (Weinheim) ; 347(8): 559-65, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24801813

RESUMEN

5-Amino-1-p-tolyl-1H-pyrazole-4-carbonitrile (1) was used for the preparation of some novel pyrazoles and pyrazolo[3,4-d]pyrimidines 2-10. Moreover, the cytotoxicity and in vitro anticancer activities of the prepared compounds were also assessed against the MCF-7 breast cancer, HepG2 liver cancer, and A549 lung carcinoma cell lines, along with investigation of the effect of the synthesized compounds on the expression of urokinase plasminogen activator (uPA). The tested compounds exhibited remarkable cytotoxic activity against MCF-7 and HepG2 cells. Among the tested compounds, 2 and 9 revealed promising anticancer activity compared to the activity of the commonly used anticancer drug, doxorubicin, by inhibiting the expression of uPA.


Asunto(s)
Antineoplásicos/síntesis química , Pirazoles/síntesis química , Pirimidinas/síntesis química , Activador de Plasminógeno de Tipo Uroquinasa/antagonistas & inhibidores , Antineoplásicos/química , Antineoplásicos/farmacología , Técnicas de Cultivo de Célula , Supervivencia Celular/efectos de los fármacos , Células Hep G2 , Humanos , Concentración 50 Inhibidora , Células MCF-7 , Estructura Molecular , Pirazoles/química , Pirazoles/farmacología , Pirimidinas/química , Pirimidinas/farmacología
16.
Molecules ; 19(5): 5459-69, 2014 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-24776812

RESUMEN

4-Imino-1-p-tolyl-1,4-dihydropyrazolo[3,4-d]pyrimidin-5-ylamine (2) and (1-p-tolyl-1H-pyrazolo[3,4-d]pyrimidin-4-yl)-hydrazine (3) were prepared starting from ethyl 4-cyano-1-p-tolyl-1H-pyrazol-5-ylimidoformate (1). The structure of compound 3 was confirmed through preparation of the pyrazole derivatives 4 and 5. Also, the synthesis and structural characterization of pyrazolo[4,3-e][1,2,4]triazolo[4,3-c]pyrimidine derivatives 7 and 9 and their isomerization to pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine derivatives 6 and 8, respectively, under different suitable reaction conditions were reported. Moreover, the syntheses of 2-substituted-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine derivatives 10 and 11 was described.


Asunto(s)
Pirazoles/síntesis química , Pirimidinas/síntesis química , Triazoles/síntesis química , Isomerismo , Estructura Molecular , Pirazoles/química , Pirimidinas/química , Relación Estructura-Actividad , Triazoles/química
17.
PLoS One ; 19(7): e0302326, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38990935

RESUMEN

In hot dry regions, photovoltaic modules are exposed to excessive temperatures, which leads to a drop in performance and the risk of overheating. The present numerical study aims to evaluate the natural air cooling of PV modules by an inclined chimney mounted at the back. The basic equations were solved using the finite volume method. The validity of the model is verified by comparison with the data available in the literature. Thermal and dynamic flow patterns are analyzed for a variety of parameters: Rayleigh numbers from 102 to 106, PV panel tilt angle from 15° to 90°, and channel aspect ratios from 1/20 to 1/5. A critical aspect ratio has been determined to minimize overheating of the PV module. According to the computational results, the tilt angle and modified Rayleigh number increase the mass flow rate and mean Nusselt number. The overheating zone with maximum temperatures is located in the upper part of the photovoltaic panel. The addition of an extension to both channel's inlet and outlet was found to improve the cooling of the photovoltaic panels; however, only the extensions downstream of the channel are truly effective. The critical lengths at which channel performance improves significantly were identified by examining the impact of longer extensions on channel performance. Increasing the extension length from 0 to 3H improves the mass flow rate by 65%, the average Nusselt number by 13.4%, and leads to an 11% decrease in maximum temperature when Ra* = 106. This cooling technique is particularly promising for hot dry regions where water is scarce.


Asunto(s)
Convección , Modelos Teóricos , Energía Solar , Frío
18.
ACS Omega ; 9(25): 27030-27046, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38947844

RESUMEN

This study aimed to increase the stability and solubility of the Algerian Satureja hortensis L. (ASHO) essential oil through nanoencapsulation. Nanoemulsions of ASHO (MF-ASHEO) were developed to evaluate their antioxidant and antimicrobial potential, stability, and cytotoxicity using microfluidization at 150 MPa for five cycles. MF-ASHO showed 8 compounds (99.56%) vs ASHEO's 26 compounds (95.46%). Carvacrol increased to 94.51%, replacing γ-terpinene, which decreased to 0.43%. The MF-ASHEO nanoemulsion had a mean particle size of 41.72 nm, a monomodal size distribution pattern, a mean ζ-potential of -39.4 mV, and a polydispersity index (PDI) mean value of 0.291. Micrographs showed spherical nanoparticles with varying diameters in nm. ASHEO was more toxic than MF-ASHEO against HepG2, Vero, and WI-38, according to the MTT and WST-1 assays. ASHEO demonstrated antiradical and antibacterial activity and inhibited biofilm formation. It also had an enhanced antifungal effect and reduced mycotoxin production. The MF-ASHEO sample showed no activity except in reducing mycotoxin production, where it performed better than ASHEO. In silico and ADME results confirmed the inhibitory action of carvacrol on the key enzymes of the aflatoxin biosynthetic mechanism and the target proteins associated with bactericidal/bacteriostatic effects. The microfluidization process dramatically affects not only the oil's volatile content but also its biological activity.

19.
Heliyon ; 10(19): e38281, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39386781

RESUMEN

Due to the increasing resistance prevalence to the last line of antibiotics, such as colistin, and the rising threat of multi-drug resistant bacteria, it is crucial to find alternative therapeutic options. The current study focuses on evaluating antibacterial activities alone and in combination with colistin of Thymus algeriensis essential oil (TA-EO) against colistin-resistant Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli co-harboring mcr-1 gene. GC/MS was used to determine the chemical composition of TA-EO. Disc diffusion and microdilution techniques were used to evaluate the antimicrobial activities of TA-EO. Synergism between colistin and TA-EO was evaluated by checkerboard assay. The major compounds of TA-EO were docked with known enzymes involved in resistance to colistin, as well as the biosynthesis of peptidoglycan and amino acids. GC/MS revealed that TA-EO was of carvacrol chemotype (67.94 %). The TA-EO showed remarkable antibacterial activities against all Gram-negative bacterial strains, with the diameter of inhibition zones varied between 30 and 50 mm and a ratio MBC/MIC equal to 1 for the vast majority of bacterial isolates. Interestingly, the checkerboard showed synergism between TA-EO and colistin against colistin-resistant Escherichia coli co-harboring mcr-1 gene (FICI˂1) and reduced the MIC of colistin by 16- to 512-fold and those of TA-EO by 4- to 16-fold. The docking study demonstrated that carvacrol had high binding free energies against MCR-1, a phosphoethanolamine transferase extracellular domain, and its catalytic domain implicated in resistance to colistin, and undecaprenyl pyrophosphate synthase in complex with magnesium which is involved in bacterial peptidoglycan biosynthesis. The molecular dynamics study for 100-ns also revealed the stability of the MCR-1/carvacrol complex with a constant surface area over the simulation. These results support using carvacrol or TA-EO as a bactericidal agent, either alone or in combination with colistin, to treat infections caused by colistin-resistant Gram-negative bacteria.

20.
ASAIO J ; 70(9): 808-818, 2024 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-38552178

RESUMEN

In kidney transplantation, pairing recipients with the highest longevity with low-risk allografts to optimize graft-donor survival is a complex challenge. Current risk prediction models exhibit limited discriminative and calibration capabilities and have not been compared to modern decision-assisting tools. We aimed to develop a highly accurate risk-stratification index using artificial intelligence (AI) techniques. Using data from the UNOS database (156,749 deceased kidney transplants, 2007-2021), we randomly divided transplants into training (80%) and validation (20%) sets. The primary measure was death-censored graft survival. Four machine learning models were assessed for calibration (integrated Brier score [IBS]) and discrimination (time-dependent concordance [CTD] index), compared with existing models. We conducted decision curve analysis and external validation using UK Transplant data. The Deep Cox mixture model showed the best discriminative performance (area under the curve [AUC] = 0.66, 0.67, and 0.68 at 6, 9, and 12 years post-transplant), with CTD at 0.66. Calibration was adequate (IBS = 0.12), while the kidney donor profile index (KDPI) model had lower CTD (0.59) and AUC (0.60). AI-based D-TOP outperformed the KDPI in evaluating transplant pairs based on graft survival, potentially enhancing deceased donor selection. Advanced computing is poised to influence kidney allocation schemes.


Asunto(s)
Inteligencia Artificial , Supervivencia de Injerto , Trasplante de Riñón , Trasplante de Riñón/métodos , Humanos , Masculino , Femenino , Persona de Mediana Edad , Donantes de Tejidos/estadística & datos numéricos , Obtención de Tejidos y Órganos/métodos , Obtención de Tejidos y Órganos/estadística & datos numéricos , Adulto , Aprendizaje Automático
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