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1.
PLoS One ; 19(4): e0302062, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38662741

RESUMEN

Numerous recently introduced chaotic systems exhibit straightforward algebraic representations. In this study, we explore the potential for identifying a global analytic first integral in a generalized 3-dimensional chaotic system (2). Our work involves detailing the model of a new 3-D chaotic system characterized by three Lyapunov exponents-positive, zero, and negative. We depict the phase trajectories, illustrate bifurcation patterns, and visualize Lyapunov exponent graphs. The investigation encompasses both local and global analytic first integrals for the system, providing results on the existence and non-existence of these integrals for different parameter values. Our findings reveal that the system lacks a global first integral, and the presence or absence of analytic first integrals is contingent upon specific parameter values. Additionally, we present a formal series for the system, demonstrating 3D and 2D projections of the system (2) for a given set of initial conditions achieved by selecting alternative values for parameters a, b, c, d, r and l.


Asunto(s)
Dinámicas no Lineales , Modelos Teóricos , Algoritmos
2.
BMC Plant Biol ; 24(1): 126, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38383286

RESUMEN

Heavy metal stress affects crop growth and yields as wheat (Triticum aestivum L.) growth and development are negatively affected under heavy metal stress. The study examined the effect of cobalt chloride (CoCl2) stress on wheat growth and development. To alleviate this problem, a pot experiment was done to analyze the role of sulfur-rich thiourea (STU) in accelerating the defense system of wheat plants against cobalt toxicity. The experimental treatments were, i) Heavy metal stress (a) control and (b) Cobalt stress (300 µM), ii) STU foliar applications; (a) control and (b) 500 µM single dose was applied after seven days of stress, and iii) Wheat varieties (a) FSD-2008 and (b) Zincol-2016. The results revealed that cobalt stress decreased chlorophyll a by 10%, chlorophyll b by 16%, and carotenoids by 5% while foliar application of STU increased these photosynthetic pigments by 16%, 15%, and 15% respectively under stress conditions as in contrast to control. In addition, cobalt stress enhances hydrogen peroxide production by 11% and malondialdehyde (MDA) by 10%. In comparison, STU applications at 500 µM reduced the production of these reactive oxygen species by 5% and by 20% by up-regulating the activities of antioxidants. Results have revealed that the activities of SOD improved by 29%, POD by 25%, and CAT by 28% under Cobalt stress. Furthermore, the foliar application of STU significantly increased the accumulation of osmoprotectants as TSS was increased by 23% and proline was increased by 24% under cobalt stress. Among wheat varieties, FSD-2008 showed better adaptation under Cobalt stress by showing enhanced photosynthetic pigments and antioxidant activities compared to Zincol-2016. In conclusion, the foliar-applied STU can alleviate the negative impacts of Cobalt stress by improving plant physiological attributes and upregulating the antioxidant defense system in wheat.


Asunto(s)
Antioxidantes , Metales Pesados , Antioxidantes/farmacología , Triticum , Clorofila A , Cobalto/toxicidad
3.
RSC Adv ; 14(4): 2369-2379, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38213971

RESUMEN

Macrocycles play a pivotal and indispensable role within the realms of both medicine and industry. In the course of our research endeavors, we have successfully synthesized five distinct macrocyclic chalcone entities, each showcasing remarkable biological and anti-oxidative properties. Furthermore, these compounds exhibit exceptional promise as potent agents for the removal of dyes in wastewater treatment processes. The synthesis of these key constituents was achieved through the judicious application of the Robinson ether synthesis and Claisen-Schmidt condensation reactions. The structures of compounds 1a-f and 2a-e were characterized by using analytical techniques such as FTIR, 1H NMR, 13C NMR, and DEPT 13C NMR spectroscopy. These macrocycles also underwent in vitro assessments to measure their antibacterial activity using the agar well diffusion method. The results revealed that the macrocyclics were more sensitive to Gram-positive than Gram-negative bacteria. For example, compound 2d exhibited an inhibition zone of 20 mm at 150 ppm. The antioxidant activity as determined via the DPPH method established that all tested compounds showed moderate radical-scavenging ability. Specifically, compound 2e (at 1000 ppm) exhibited antioxidant activity of 79% inhibition of radicals, in comparison to 90% for the standard ascorbic acid. The latter was demonstrated by using methylene blue as an adsorbate under simulated wastewater conditions. Outstandingly, the most effective compounds were 2d and 2c, which achieved removal rates of 96.54% and 92.37%, respectively, for methylene blue dye.

4.
Forensic Sci Res ; 8(4): 313-320, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38405627

RESUMEN

Soil is commonly collected from an outdoor crime scene, and thus it is helpful in linking a suspect and a victim to a crime scene. The chemical profiles of soils can be acquired via chemical instruments such as Ultra-Performance Liquid Chromatography (UPLC). However, the UPLC chromatogram often interferes with an unstable baseline. In this paper, we compared the performance of five baseline correction (BC) algorithms, i.e. asymmetric least squares (AsLS), fill peak, iterative restricted least squares, median window (MW), and modified polynomial fitting, in discriminating 30 chromatograms of brownish soils by five locations of origin, i.e. PP, HK, KU, BL, and KB. The performances of the preprocessed sub-datasets were first visually inspected through the mean chromatograms and then further explored via scores plots of principal component analysis (PCA). Eventually, the predictive performances of the partial least squares-discriminant analysis (PLS-DA) models estimated from 1 000 pairs of training and testing samples (i.e. prepared via iterative random resampling split at 75:25) were studied to identify the best BC method. Mean raw chromatograms of the 10 soil samples were different from each other, with evident fluctuated baselines. AsLS and MW corrected chromatograms demonstrated the most significant improvement compared with the raw counterpart. Meanwhile, the scores plot of PCA revealed that most of the sub-datasets produced three separate clusters. Then, the sub-datasets were modelled via the PLS-DA technique. MW emerged as the excellent BC method based on the mean prediction accuracy estimated using 1 000 pairs of training and testing samples. In conclusion, MW outperformed the other BC methods in correcting the UPLC data of soil. Key points: UPLC data of soil interfere with baseline drifts.BC can improve the quality of the pixel-level UPLC data.MW emerges as the most desired algorithm in improving the quality of UPLC data of soil.

5.
Hepat Oncol ; 9(3): HEP44, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36176484

RESUMEN

Materials & methods: High dose rate interstitial brachytherapy (HDR-IBT) treatment plan for 15 metastatic liver lesions in a patient with pancreatic cancer was retrieved and analyzed for liver dose parameters and diaphragm dose. Serial 18F-FDG PET-CT scans were reviewed for disease response assessment and left liver lobe volume. Serial laboratory records were analyzed for liver parameters. Results: Left liver lobe volume increased from 241 cm3 pre-HDR-IBT to estimated 600 cm3 after seven sessions of HDR-IBT. Metabolic complete response (CR) and subsequently pathological CR was confirmed in the right hepatotectomy specimen for all the 15 PET-CT avid lesions treated with HDR-IBT. Maximum diaphragm dose in a single fraction was 82 Gy. The liver parameters were stable and patient did not develop radiation induced liver disease. Discussion: This is the largest reported series of HDR-IBT to liver lesions in a single patient. This first ever reported combined treatment of immunotherapy (IT) and HDR-IBT had likely rendered this patient disease free both at local the liver and systemically. Metabolic CR by PET-CT can be seen as early as 46 days after HDR-IBT. Diaphragm can tolerate very high doses of radiation and repeated treatment. Conclusion: In this patient HDR-IBT for multiple liver lesions with IT is well tolerated. PET-CT can be used for response assessment of HDR-IBT liver. Synergistic effect of IT with HDR-IBT and it's role as bridging for liver resection has clinical potential and should be further studied in prospective trials.

6.
Diagnostics (Basel) ; 11(4)2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33919817

RESUMEN

A multiplex rapid detection system, based on a PCR-lateral flow biosensor (mPCR-LFB) was developed to identify Salmonella Typhi and Salmonella Paratyphi A from suspected carriers. The lower detection limit for S. Typhi and S. Paratyphi A was 0.16 and 0.08 ng DNA equivalent to 10 and 102 CFU/mL, respectively. Lateral flow biosensor was used for visual detection of mPCR amplicons (stgA, SPAint, ompC, internal amplification control) by labeling forward primers with fluorescein-isothiocyanate (FITC), Texas Red, dinitrophenol (DNP) and digoxigenin (DIG) and reverse primers with biotin. Binding of streptavidin-colloidal gold conjugate with the amplicons resulted in formation of a red color dots on the strip after 15-20 min of sample exposure. The nucleic acid lateral flow analysis of the mPCR-LFB was better in sensitivity and more rapid than the conventional agarose gel electrophoresis. Moreover, the mPCR-LFB showed 100% sensitivity and specificity when evaluated with stools spiked with 100 isolates of Salmonella genus and other bacteria. A prospective cohort study on stool samples of 1176 food handlers in outbreak areas (suspected carriers) resulted in 23 (2%) positive for S. Typhi. The developed assay has potential to be used for rapid detection of typhoid carriers in surveillance program.

7.
Oxf Med Case Reports ; 2021(2): omaa132, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33614043

RESUMEN

Hypertensive emergency in the paediatric population is not uncommon. However, due to its numerous etiologies, care should be taken in determining the approach of management. We report a case of a child who presented with double vision, giddiness and elevated blood pressure. Blood investigations were normal. Renal ultrasound and magnetic resonance imaging of the abdomen were performed which both showed findings suspicious of a large heterogeneous mass at the lower pole of the left kidney with dysplastic right kidney. A final diagnosis of bilateral vesicoureteric reflux with left compensatory hypertrophy was made based upon micturating cystourethrography findings and was later confirmed by 99mTc-dimercaptosuccinic acid (DMSA) study. The objective of this case is to share the importance of the appropriate choice of radiological examinations, not only in achieving an accurate diagnosis but to ensure that unnecessary investigations are avoided.

8.
Radiat Prot Dosimetry ; 188(2): 213-221, 2020 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-31885043

RESUMEN

The aim of this study was to propose local diagnostic reference levels (LDRLs) for the most common computed tomography (CT) examinations (including contrast and non-contrast scan phase) performed at Advanced Medical and Dental Institute (AMDI), Universiti Sains Malaysia (USM), Malaysia. A retrospective CT dose survey of 1488 subjects from January 2015 until December 2018 was performed at AMDI USM, Malaysia. The proposed DRLs were established at 50th and 75th percentile of dose distribution for all dose metrics (CT dose index [CTDI]; CTDIvol, CTDIw and dose-length product). The proposed LDRLs were compared with national DRLs and other established DRLs. The 10 most common CT examinations at AMDI were thorax-abdomen-pelvis (TAP) CT (46%), followed by pelvis CT (17%), abdomen-pelvis CT (10%), brain/head CT (9%) and other CT protocols. The local DRLs were established using the third quartile values of dose distribution and were categorized based on CT region protocols. Most of the proposed DRLs were exceeded the national DRLs (63%) and other international DRLs (67%). From the dose auditing, almost half of the recent dose data (for year 2018) exceeded the proposed local DRLs and the unusual dose were observed in TAP, brain/head and pelvis CT examinations. The unusual higher dose could be due to higher mAs settings, higher number of scan phase for contrast study and higher pitch factor. The local DRLs should be established for dose optimization and reduction of the occurrence of excessive radiation exposure to the patients. The establishment of the Ads and LDRLs should also consider all the factors that affect the variation in DRLs such as CT technology, scanning protocols and population characteristics. The local dose distribution should always be revised for improvement of the current local practice.


Asunto(s)
Niveles de Referencia para Diagnóstico , Tomografía Computarizada por Rayos X , Humanos , Malasia , Dosis de Radiación , Valores de Referencia , Estudios Retrospectivos
9.
Int J Biol Macromol ; 107(Pt A): 1030-1038, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28939521

RESUMEN

Successful use of tissue expanders depends on the quality of expanded tissue. This study evaluates the impact of anisotropic self-inflating tissue expander (SITE) on the biomechanics of skin. Two different SITE were implanted subcutaneously on sheep scalps; SITE that requires 30days for maximum expansion (Group A; n=5), and SITE that requires 21days for maximum expansion (Group B; n=5). Control animals (n=5) were maintained without SITE implantation. Young's Modulus, D-periodicity, overlap and gap region length, diameter, and height difference between overlap and gap regions on collagen fibrils were analyzed using atomic force microscopy. Histology showed no significant differences in dermal thickness between control and expanded skin of groups A and B. Furthermore, most parameters of expanded skin were similar to controls (p>0.05). However, the height difference between overlap and gap regions was significantly smaller in group B compared to both control and group A (p<0.01). Strong correlation was observed between Young's Modulus of overlap and gap regions of the control and group A, but not group B. Results suggest that a relatively slower SITE can be useful in reconstructive surgery to maintain the biomechanical properties of expanded skin.


Asunto(s)
Colágeno/química , Cuero Cabelludo/química , Piel/química , Dispositivos de Expansión Tisular , Animales , Fenómenos Biomecánicos , Colágeno/ultraestructura , Módulo de Elasticidad , Matriz Extracelular , Microscopía de Fuerza Atómica , Cuero Cabelludo/ultraestructura , Ovinos , Piel/ultraestructura , Expansión de Tejido/métodos
10.
Adv Bioinformatics ; 2017: 5124165, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28932239

RESUMEN

The inhibition of dipeptidyl peptidase-IV (DPPIV) is a popular route for the treatment of type-2 diabetes. Commercially available gliptin-based drugs such as sitagliptin, anagliptin, linagliptin, saxagliptin, and alogliptin were specifically developed as DPPIV inhibitors for diabetic patients. The use of Gynura bicolor in treating diabetes had been reported in various in vitro experiments. However, an understanding of the inhibitory actions of G. bicolor bioactive compounds on DPPIV is still lacking and this may provide crucial information for the development of more potent and natural sources of DPPIV inhibitors. Evaluation of G. bicolor bioactive compounds for potent DPPIV inhibitors was computationally conducted using Lead IT and iGEMDOCK software, and the best free-binding energy scores for G. bicolor bioactive compounds were evaluated in comparison with the commercial DPPIV inhibitors, sitagliptin, anagliptin, linagliptin, saxagliptin, and alogliptin. Drug-likeness and absorption, distribution, metabolism, and excretion (ADME) analysis were also performed. Based on molecular docking analysis, four of the identified bioactive compounds in G. bicolor, 3-caffeoylquinic acid, 5-O-caffeoylquinic acid, 3,4-dicaffeoylquinic acid, and trans-5-p-coumaroylquinic acid, resulted in lower free-binding energy scores when compared with two of the commercially available gliptin inhibitors. The results revealed that bioactive compounds in G. bicolor are potential natural inhibitors of DPPIV.

11.
Nat Prod Commun ; 10(4): 617-20, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25973490

RESUMEN

Four new coumarins, isomurralonginol senecioate (1), isomurralonginoic acid (2), murrangatin 2'-formate (3), and meranzin hydrate 2'-palmitate (4), were isolated from the vegetative branches of Murraya exotica together with 33 known compounds. The structures of the new compounds were determined from chemical and spectroscopic data.


Asunto(s)
Cumarinas/química , Cumarinas/farmacología , Murraya/química , Egipto , Estructura Molecular
12.
Chem Pharm Bull (Tokyo) ; 56(11): 1535-45, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18981602

RESUMEN

In bioassay-guided searches for novel bioactive natural products from higher plants of the Egyptian flora, two new eudesmane sesquiterpene derivatives, 3alpha-hydroxyilicic acid methyl ester (1) and 2alpha-hydroxy-4-epi-ilicic acid (2), together with 11 known sesquiterpenes were isolated from bioactive fractions of the active epigeal parts extracts of Dittrichia graveolens (L.) GREUTER (Asteraceae) growing in the coastal regions of northwestern Egypt. Four other known sesquiterpene lactones with different carbon skeletons, named 2alpha-hydroxy-2R-xanthalongin (8), 4-epi-isoinuviscolide (9), 8-epi-helenalin (10), and bigelovin (11), were also isolated for the first time from the same source. The stereochemical structures of the isolated compounds were elucidated on the basis of physical and spectroscopic methods including UV, IR, 1H-, 13C-NMR, distortionless enhancement by polarization transfer, 2D NMR, 1H-1H correlation spectroscopy, 1H-13C heteronuclear single-quantum coherence, 1H-13C heteronuclear multiple-bond connectivity, 1H-1H nuclear Overhauser effect spectroscopy experiments, and high-resolution mass spectrometry, as well as some chemical transformations. The antimicrobial, antiinflammatory, and antipyretic activities of D. graveolens extracts and chromatographic fractions were carried out and the various bioactivities of our findings are discussed.


Asunto(s)
Inula/química , Sesquiterpenos de Eudesmano/análisis , Sesquiterpenos/análisis , Analgésicos no Narcóticos/farmacología , Animales , Antibacterianos/análisis , Antibacterianos/química , Antiinflamatorios no Esteroideos/farmacología , Antifúngicos/análisis , Antifúngicos/química , Bacterias/efectos de los fármacos , Temperatura Corporal/efectos de los fármacos , Edema/inducido químicamente , Edema/prevención & control , Fiebre/inducido químicamente , Fiebre/prevención & control , Hongos/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Masculino , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Ratas
13.
Chem Pharm Bull (Tokyo) ; 53(9): 1180-2, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16141593

RESUMEN

Bismurrangatin and murramarin A, two new coumarins, were isolated from the vegetative branches of Murraya exotica. Murramarin A is a rare type of bicoumarin that connects two coumarin moieties by orthoester structure. The structures were elucidated based on spectroscopic methods, especially by 2D-NMR experiments.


Asunto(s)
Cumarinas/química , Murraya/química , Cumarinas/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta
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