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1.
PLoS One ; 19(1): e0296365, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38170695

RESUMEN

In this paper, we investigate the properties of timelike and spacelike shifted-knots Bézier surfaces in Minkowski space-[Formula: see text]. These surfaces are commonly used in mathematical models for surface formation in computer science for computer-aided geometric design and computer graphics, as well as in other fields of mathematics. Our objective is to analyze the characteristics of timelike and spacelike shifted-knots Bézier surfaces in Minkowski space-[Formula: see text]. To achieve this, we compute the fundamental coefficients of shifted-knots Bézier surfaces, including the Gauss-curvature, mean-curvature, and shape-operator of the surface. Furthermore, we present numerical examples of timelike and spacelike bi-quadratic (m = n = 2) and bi-cubic (m = n = 3) shifted-knots Bézier surfaces in Minkowski space-[Formula: see text] to demonstrate the applicability of the technique in Minkowski space.


Asunto(s)
Gráficos por Computador , Modelos Teóricos , Diseño Asistido por Computadora , Matemática
2.
Bol. latinoam. Caribe plantas med. aromát ; 21(3): 352-364, mayo 2022. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-1396915

RESUMEN

The antioxidant activity and the inhibitory potential of α-amylase of lyophilized hydroethanolic extracts of Conocarpus erectus leaves obtained by ultrasonication were determined. The most potent extract was subjected to ultra-high performance liquid chromatography system equipped with mass spectrometer for metabolite identification. The identified metabolites were docked in α-glucosidase to assess their binding mode. The results revealed that 60% ethanolic extract exhibited highest ferric reducing antioxidant power (4.08 ± 0.187 mg TE/g DE) and α-amylase inhibition (IC50 58.20 ± 1.25 µg/mL. The metabolites like ellagic acid, 3-O-methyl ellagic acid, ferujol, 5, 2 ́-dihydroxy-6,7,8-trimethyl flavone and kaempferol glucoside were identified in the extract and subjected to molecular docking studies regarding α-amylase inhibition. The comparison of binding affinities revealed 3-O-methyl ellagic acid as most effective inhibitor of α-amylase with binding energy of -14.5911 kcal/mol comparable to that of acarbose (-15.7815 kcal/mol). The secondary metabolites identified in the study may be extended further for functional food development with antidiabetic properties.


Se determinó la actividad antioxidante y el potencial inhibidor de la α-amilasa de extractos hidroetanólicos liofilizados de hojas de Conocarpus erectus obtenidos por ultrasónicación. El extracto más potente se sometió a un sistema de cromatografía líquida de ultra alto rendimiento equipado con un espectrómetro de masas para la identificación de metabolitos. Los metabolitos identificados se acoplaron en α-glucosidasa para evaluar su modo de unión. Los resultados revelaron que el extracto etanólico al 60% exhibió el mayor poder antioxidante reductor férrico (4.08 ± 0.187 mg TE/g DE) e inhibición de la α-amilasa (IC50 58.20 ± 1.25 µg/mL. Los metabolitos como el ácido elágico, 3-O-metil elágico ácido, ferujol, 5, 2 ́-dihidroxi-6,7,8-trimetil flavona y kaempferol glucósido se identificaron en el extracto y se sometieron a estudios de acoplamiento molecular con respecto a la inhibición de la α-amilasa. La comparación de las afinidades de unión reveló 3-O-metil El ácido elágico como inhibidor más eficaz de la α-amilasa con una energía de unión de -14,5911 kcal/mol comparable a la de la acarbosa (-15,7815 kcal/mol). Los metabolitos secundarios identificados en el estudio pueden ampliarse aún más para el desarrollo funcional de alimentos con propiedades antidiabéticas.


Asunto(s)
Extractos Vegetales/química , alfa-Amilasas/antagonistas & inhibidores , Myrtales/química , Antioxidantes/química , Benzopiranos/análisis , Técnicas In Vitro , Extractos Vegetales/farmacología , Hojas de la Planta/química , Simulación del Acoplamiento Molecular , Antioxidantes/farmacología
3.
Bol. latinoam. Caribe plantas med. aromát ; 20(6): 660-671, nov. 2021. tab, ilus
Artículo en Inglés | LILACS | ID: biblio-1369981

RESUMEN

Search for safe antioxidants and novel nutraceuticals urged to evaluate the antioxidant, anti-acetylcholine esterase and anti-lipoxygenase activity of various leaf extracts of Conocarpus lancifolius. Extraction was optimized from freeze dried plant extracts quenched with liquid nitrogen using water, ethanol, methanol, hexane, ethyl acetate and chloroform. Maximum extract yield, total phenolic contents and total flavonoid contents were obtained in case of ethanolic extraction. The highest 2,2-diphenyl-1-picrylhydrazylradical scavenging in terms of IC50 value of 55.26 µg/mL was observed for ethanolic leaf extract. The acetylcholine esterase and lipoxygenase inhibitory activities (IC50) were also observed for ethanolic extract. These findings for ethanolic extract were statistically significant when compared with other extracts (ρ<0.05). The haemolytic % values indicated that all extracts were associated with very low or negligible toxicity. The epicatechin, isorhamnetin, rutin, scopoleptin, skimmianine, quercetin-3-O-α-rhamnoside, quercetin-3-O-ß-glucoside, cornoside, creatinine, choline, pyruvic acid, α-hydroxybutyric acid, phyllanthin and hypophyllanthin were identified as major functional metabolites in ethanolic leaf extract of C. lancifoliusby 1H-NMR. The identified metabolites were probably responsible for the pharmacological properties of C.lancifolius. The findings may be utilized as pharmacological leads for drug development and food fortification.


Se insta a la búsqueda de antioxidantes seguros y nuevos nutracéuticos para evaluar la actividad antioxidante, anti-acetilcolina esterasa y anti-lipoxigenasa de varios extractos de hojas de Conocarpus lancifolius. La extracción se optimizó a partir de extractos de plantas liofilizados enfriados con nitrógeno líquido usando agua, etanol, metanol, hexano, acetato de etilo y cloroformo. En el caso de extracción etanólica se obtuvo el rendimiento máximo de extracto, el contenido de fenoles totales y el contenido de flavonoides totales. La mayor eliminación de radicales 2,2-difenil-1-picrilhidrazilo en términos de valor de CI50 de 55,26 µg/mL se observó para el extracto de hoja etanólico. También se observaron las actividades inhibidoras de la acetilcolina esterasa y lipoxigenasa (CI50) para el extracto etanólico. Estos hallazgos para el extracto etanólico fueron estadísticamente significativos en comparación con otros extractos (ρ<0.05). Los valores del % hemolítico indicaron que todos los extractos estaban asociados con una toxicidad muy baja o insignificante. Se identificaron la epicatequina, isorhamnetina, rutina, escopoleptina, skimmianina, quercetina-3-O-α-ramnosido, quercetina-3-O-ß-glucósido, cornosido, creatinina, colina, ácido pirúvico, ácido α-hidroxibutírico, filantrina e hipofillantina. como metabolitos funcionales principales en el extracto etanólico de hojas de C. lancifoliuspor 1H-NMR. Los metabolitos identificados probablemente fueron responsables de las propiedades farmacológicas de C. lancifolius. Los hallazgos pueden utilizarse como pistas farmacológicas para el desarrollo de fármacos y la fortificación de alimentos.


Asunto(s)
Extractos Vegetales/farmacología , Combretaceae/química , Antioxidantes/farmacología , Fenoles/análisis , Flavonoides/análisis , Técnicas In Vitro , Extractos Vegetales/química , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/química , Depuradores de Radicales Libres , Inhibidores de la Lipooxigenasa/farmacología , Inhibidores de la Lipooxigenasa/química , Etanol , Antioxidantes/química
4.
Arch Microbiol ; 203(8): 4901-4912, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34250573

RESUMEN

Deleterious effects of artificially applied chemicals have highlighted the significance of biocontrol agents as suitable substitute for sustainable agriculture. In present study, three endophytic bacterial strains SV7, SV10 and LV19 showed extensive range of antifungal as well as plant growth promoting activities signifying potential to accomplish the requirement. Phylogenetic analysis revealed 100% similarity of three strains with taxon Firmicute. However, there was division among these isolates on basis of subgroups as SV7 belonged to Exiguobacterium auranticum, SV10 belonged to Paenibacillus sp. and LV19 was best fit in subgroup Priestia koreensis. All strains showed antifungal activity against Fusarium oxysporum on three different media (PDA, NA, LA) with maximum activity (53%) of LV19 strain on NA and least activity (13%) on PDA medium as recorded by zones of inhibition. In growth promotion experiments, combination of LV19 with Fusarium significantly suppressed chances of Fusarium wilt which is commonly caused by Fusarium oxysporum in sunflower plants. Diverse growth parameters (seed germination percentage, lengths and fresh weights of root and shoot) were significantly increased from 34 to 909% over pathogen infected plants only which was further proved by their root colonization analysis. Based on most efficient growth promotion by LV19 strain, expression of five plant defense related genes (SOD, PAL, NPR1, PR5, Chitinase) was evaluated revealing enhanced expression by 1.7-270-folds in consortium of LV19 and Fusarium. Thus, current study provided a scientific justification that bacterial strains in specific LV19 (Priestia koreensis) could be further developed as biocontrol agent with potential of plant growth promotion.


Asunto(s)
Fusarium , Helianthus , Paenibacillus , Filogenia , Enfermedades de las Plantas/prevención & control , Raíces de Plantas
5.
Cureus ; 13(1): e12837, 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33628695

RESUMEN

Background and objective The incidence of post-surgical complications (PSCs) after curative resection of non-metastatic colorectal cancer (CRC) is very widespread and evident. Some studies suggest that PSCs often predict poor long-term oncological outcomes. However, the available data on the topic is often controversial. The aim of this systematic review and meta-analysis was to study the effect of postoperative complications (POCs) on long-term oncological outcomes following curative resection of non-metastatic (stage I-III) CRC. Methods A comprehensive search of MEDLINE® and Excerpta Medica dataBASE (EMBASE) databases was performed via the Ovid platform, by using controlled vocabulary as well as natural language terms for POCs, outcomes, and CRC. Two authors independently screened the studies and extracted data. Conflicts were resolved by discussion among authors and also independently with the help of a third author. Meta-analysis was performed using a random-effects model (REM) to calculate pooled estimates for overall survival (OS), disease-free survival (DFS), and overall recurrence. Results Overall, 3,836 studies were initially screened, and 16 studies involving 37,192 patients were ultimately selected for final inclusion in the analysis. Meta-analysis of these studies showed that PSCs following non-metastatic CRC surgery predicted worse OS rates [hazard ratio (HR): 1.36; 95% CI: 1.15-1.61; p<0.00001], DFS (HR: 1.41; 95% CI: 1.11-1.80; p<0.00001), and overall recurrence (HR: 1.19; 95% CI: 1.04-1.37; p=0.01). Conclusion Based on our findings, PSCs predict poor OS rates, DFS, and overall recurrence following curative resection of non-metastatic CRC.

6.
Front Pharmacol ; 12: 787891, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35069204

RESUMEN

Objective: To determine the awareness and attitudes of the Pakistani population regarding physician-pharmaceutical company interactions. Methods: The data were collected from primary health care clinics and pharmacy outlets located within cities of six randomly selected districts of the Punjab Province. Those individuals (age ≥18 years) who have just completed their visit to the physician and well understand Urdu language were approached. Descriptive analysis was performed for all variables by using SPSS (IBM version 26). Results: A total of 3,852 participants fully completed the study out of 4,301 (response rate 89.5%). Of those, 30.9% were female; two-thirds (66.7%) were aware of drug representatives' visits to clinics. The majority were aware of pharmaceutical company material presence (or absence) in the physicians' rooms (56.6%), company items with logos (66.8%), patient education materials (73.4%), and 60.8% thought that receiving gifts from companies was "wrong/unethical" practice for physicians, which was lower in comparison to other professions such as judges to accept gifts from lawyers (65.6%) and professional sports umpires to acknowledge gifts (64.3%). A minority said that they have lower trust on physicians for using drug company notepads or pens (16.7%), going on trips sponsored by the company (16.7%), accepting gifts <15,000 PKR (90.3 US$) (26.7%), and accepting gifts >15,000 PKR (90.3 US$) (40.0%). Conclusion: Survey participants were well aware of physician-pharmaceutical company interactions. Participants were more knowledgeable regarding the pharmaceutical company presence (or absence) in physicians' offices than about gift-related practices of physicians. Trust on the physician was not affected by small gifts but by the large gifts.

7.
Saudi J Biol Sci ; 27(2): 720-726, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32210694

RESUMEN

Endophytic bacterial diversity shows an intricate network of interactions with host plants as they reside in various tissues and organs at certain stages or all stages of their life cycle stimulating the plant growth and fitness. Sunflower is a trendy oilfield crop and variation in its varieties is associated with the dynamics of endophytic diversity. The present study is undertaken to identify and compare the ecological niche of endophytic bacterial communities amongst different tissues of two hybrids varieties Hysun-33 and Hysun-39 of sunflower (Helianthus annuus) at three developmental stages which are vegetative stage I (after 15 days of seeds germination), vegetative stage II (after 30 days of germination) and reproductive stage (after 90 days of germination). A total of 74 endophytes from Hysun-33 and 115 endophytes from Hysun-39 have been isolated from different tissues and growth stages. Amongst plant parts, root tissues harbored higher bacterial inhabitants (44) followed by stem (33), leaf (30) and flower (7) of Hysun-39. Likewise, Hysun-33 endophytes colonized roots more abundantly followed by leaves, stem and flowers. All strains are found to be gram positive with the exception of only RA9 from Hysun-33 and RB9 from Hysun-39 that are gram negative. Among different growth stages, the maximum bacterial population (CFU of 320 × 103) was found amongst root microflora at vegetative stage II of plant in Hysun-39 variety as compared to root endophytes of Hysun-33 having (CFU of 10 × 103). The evaluation of their growth promoting features revealed that among 74 isolates of Hysun-33, 70% exhibited the ability of hydrogen cyanide production, 43% IAA production, 36% siderophore production and 4% nitrogen fixation and also phosphate solubilization. However among 115 isolates of Hysun-39, 64% appeared as hydrogen cyanide producers, 56% IAA producers, 33% siderophore producers, 2% nitrogen fixers and 4% as phosphate solubilizers. Therefore our study reveals understanding of wide-ranging diversity of endophytic bacteria and their beneficial relationship with internal tissues of host plant which may recommend their implementation to crops for better development of agricultural systems.

8.
Transfus Med Hemother ; 40(5): 362-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24273491

RESUMEN

BACKGROUND: Scientific data regarding effects of platelet transfusion on platelet count in dengue-related thrombocytopenia is scanty. METHODS: A single center, randomized non-blinded trial was conducted on adult patients with dengue fever and platelet counts less than 30,000/µl. Patients were randomized to treatment and control group. Treatment group received single donor platelets. Patients with post-transfusion platelet increment (PPI) ≥10,000/µl and/or corrected count increment (CCI) ≥5,000/µl 1 h post-transfusion were considered responders. Primary outcome was platelet count increments at 24 and 72 h. RESULTS: 87 patients were enrolled, and 43 (48.2%) received platelet transfusion. Mean PPI and CCI at 1 h post-transfusion in the treatment group were 18,800/µl and 7,000/µl respectively. 22 (53.6%) patients in the treatment group were non-responders. Mean platelet increments at 24 and 72 h were higher in the treatment group as compared to the control group. Responders showed significantly higher increments when compared to non-responders and the control group at 24 h (p = 0.004 and p ≤ 0.001, respectively) and 72 h (p = 0.001 and p ≤ 0.001, respectively). Significant differences were found between non-responders and the control group at 24 h (p ≤ 0.001), but not at 72 h (p = 0.104). Patients with lower baseline platelet count were more likely to be non-responders. Platelet transfusion neither prevented development of severe bleeding nor shortened time to cessation of bleeding. Three severe transfusion reactions and two deaths occurred in treatment group. CONCLUSION: In this trial, almost half the patients showed no response to a high-dose platelet transfusion. Platelet transfusion did not prevent development of severe bleeding or shorten time to cessation of bleeding and was associated with significant side effects. Therefore, platelet transfusion should not be routinely done in the management of dengue fever.

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