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1.
J Periodontal Res ; 58(1): 22-28, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36321414

RESUMEN

BACKGROUND: There is scarce information about the relationship between periodontal disease and osteoarthritis. This study investigated the effect of surgically induced osteoarthritis on alveolar bone loss in experimental periodontitis in rats. METHODS: 12 rats were divided into test and control groups. On day 1, the animals were anaesthetized, and silk ligatures were ligated around 6 maxillary posterior teeth in each animal from both groups. Surgical induction of osteoarthritis was performed on the left knees in the test group. No knee surgeries were performed in the control group. The ligatures were kept in place for 30 days, at which time the animals were euthanatized, and the maxillae and knee joints were harvested and processed for histological analysis. The alveolar bone loss was assessed using a zoom stereomicroscope. RESULTS: The knee joint histologic sections of the control group showed normal joint features, whereas in the test group there were substantial changes typical of osteoarthritis, including wide joint spaces, prominent monocytic infiltration of the synovium, invasion of periarticular bone, and decreased chondrocyte density. Comparison of the bone height between the groups showed a significantly higher bone loss in the test than in the control group The marginal mean bone height, adjusted for covariates and the intraclass correlation between sites, was 1.19 and 0.78 mm in the test and control groups, respectively (p < .0001). CONCLUSIONS: Surgically induced osteoarthritis leads to greater alveolar bone loss in the experimental periodontitis model in rats.


Asunto(s)
Pérdida de Hueso Alveolar , Osteoartritis , Periodontitis , Ratas , Animales , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/patología , Periodontitis/complicaciones , Periodontitis/diagnóstico por imagen , Periodontitis/patología , Osteoartritis/complicaciones , Osteoartritis/diagnóstico por imagen , Modelos Animales de Enfermedad
2.
J Enzyme Inhib Med Chem ; 38(1): 2281264, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37985494

RESUMEN

A library of N-benzylpyridinium-based compounds, 7a-j and 8a-j, was designed and synthesised as potential acetylcholinesterase) AChE (inhibitors. An in vitro assay for the synthesised compounds showed that most compounds had significant AChE inhibitory activities at the nanomolar and submicromolar levels. The benzyl (8a) and fluoro (8b) derivatives were the most active, with IC50 values ≤56 nM. Compound 7f, which had a benzyl moiety, showed the highest potency among all the target compounds, with an IC50 value of 7.5 ± 0.19 nM against AChE, which was higher than that of the activities of tacrine (IC50 = 30 ± 0.2 nM) and donepezil (IC50 = 14 ± 0.12 nM). Compounds with vanillin moieties exhibited antioxidant activity. Among the tested compounds, four derivatives (7f, 7 g, 8f, and 8 g) exhibited superior AChE inhibitory activity, with Ki values of 6-16 nM, which were potent in the same range as the approved drug, donepezil. These compounds showed moderate antioxidant activities, as indicated by the results of the ABTS assay.


Asunto(s)
Enfermedad de Alzheimer , Curcumina , Humanos , Donepezilo , Inhibidores de la Colinesterasa/farmacología , Antioxidantes/farmacología , Relación Estructura-Actividad , Acetilcolinesterasa/metabolismo , Dolor , Simulación del Acoplamiento Molecular
3.
BMC Plant Biol ; 22(1): 462, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36167520

RESUMEN

To generate high-yielding cultivars with favorable fiber quality traits, cotton breeders can use information about combining ability and gene activity within a population to locate elite parents and potential F1 crosses. To this end, in the current study, twelve cotton parents (eight genotypes as female parents and four testers) and their F1 crosses obtained utilizing the linex tester mating design were evaluated for their general and specialized combining abilities (GCA and SCA, respectively) of yield traits. The findings showed that for all the investigated variables, variances owing to genotypes, parents, crosses, and parent vs cross showed extremely significant (P ≤ 0.01) differences. Additionally, throughout the course of two growing seasons, the mean squares for genotypes (parents and crosses) showed strong significance for all the variables under study. The greatest and most desired means for all the examined qualities were in the parent G.94, Pima S6, and tester G.86. The best crossings for the qualities examined were G.86 (G.89 × G.86), G.93 × Suvin, and G.86 × Suvin. The parents' Suvin, G89x G86 and TNB were shown to have the most desired general combining ability effects for seed cotton yield/plant, lint yield/plant, boll weight, number of bolls/plants, and lint index, while Suvin, G.96 and pima S6 were preferred for favored lint percentage. For seed cotton yield, lint percentage, boll weight, and number of bolls per plant per year, the cross-G.86 x (G.89 × G.86) displayed highly significant specific combining ability impacts. The crosses G.86 × Suvin, Kar x TNB, G.93 × Suvin, and G.93 × TNB for all the studied traits for each year and their combined were found to have highly significant positive heterotic effects relative to better parent, and they could be used in future cotton breeding programs for improving the studied traits.


Asunto(s)
Gossypium , Yoduro de Potasio , Fibra de Algodón , Cruzamientos Genéticos , Egipto , Gossypium/genética , Vigor Híbrido , Fitomejoramiento
4.
Trop Anim Health Prod ; 54(5): 286, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36083376

RESUMEN

This work was designed to evaluate the efficacy of a postbiotic compound produced by stabilized non-viable Lactobacilli on the health, growth performance, immunity, and gut status against Escherichia coli (E. coli) challenge of broiler chickens. A total of 400, day-old broiler chicks were allocated into 4 equal groups (1-4) consisting of 100; each assigned into 2 equal replicates (50 each). Chickens in the 1st group were received the dry form of the compound at doses of 1 kg and 0.5 kg/ton feed for starter and grower, and the finisher diets, respectively. Chickens in the 2nd group were given the aqueous form of the compound in a dose of 4 mL/L of the drinking water during the first 3 days of life and at a day before and after each vaccination. Feed and water treatment regimens were administered to chickens in the 3rd group. Group 4 was kept without treatment. Each bird in the 1st, 2nd, 3rd, and 4th group was challenged with E. coli (O78) at 1-week-old. All groups were kept under observation till 5-week-old. Statistical analysis included one-way ANOVA and other methods as described with significant differences at P ≤ 0.05. The results indicated that feed and water treatments with the postbiotic compound induced more significant (P ≤ 0.05) amelioration of a disease picture, enhancement of growth performance, boosting of immune response, improvement of bursa of Fabricius/body weight ratio, and reduction of intestinal coliform count in challenged chickens when compared with challenged non-treated chickens. In conclusion, the postbiotic compound either in a dry and/or an aqueous form is recommended for improving the health, performance, and immunity of colisepticaemic broiler chickens.


Asunto(s)
Pollos , Infecciones por Escherichia coli , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Suplementos Dietéticos , Escherichia coli/fisiología , Infecciones por Escherichia coli/prevención & control , Infecciones por Escherichia coli/veterinaria , Lactobacillus
5.
Invest New Drugs ; 39(1): 226-231, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32851510

RESUMEN

Glioblastoma is a fast-growing primary brain tumor observed in adults with the worst prognosis. Preclinical studies have demonstrated the encouraging anticancer activity of statins. This study evaluated the efficacy of atorvastatin in combination with standard therapy in patients with glioblastoma. In this prospective, open-label, single-arm, phase II study, patients were treated with atorvastatin in combination with the standard glioblastoma therapy comprising radiotherapy and temozolomide. The primary endpoint was progression-free survival (PFS) at 6 months (PFS-6). Among 36 patients enrolled from January 2014 to January 2017, the median age was 52 (20-69) years; 22% of the patients were aged ≥60 years, and 62% were male. Patients received atorvastatin for a median duration of 6.2 (0.3-28) months. At a median follow-up of 19 months, the PFS-6 rate was 66%, with a median PFS of 7.6 (5.7-9.4) months. In terms of Grade ≥ 3 hematological adverse events, thrombocytopenia and neutropenia occurred in 7% and 12% of patients, respectively. In multivariate analyses, high baseline low-density lipoprotein levels were associated with worse survival (P = 0.046). Atorvastatin was not shown to improve PFS-6. However, this study identified that high low-density lipoprotein levels are an independent predictor of poor cancer-related outcomes. Future clinical trials testing statins should aim to enroll patients with slow-growing tumors.Clinical trial information: NCT0202957 (December 12, 2013).


Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Atorvastatina/uso terapéutico , Neoplasias Encefálicas/terapia , Quimioradioterapia/métodos , Glioblastoma/terapia , Temozolomida/uso terapéutico , Adulto , Anciano , Antineoplásicos Alquilantes/administración & dosificación , Antineoplásicos Alquilantes/efectos adversos , Atorvastatina/administración & dosificación , Atorvastatina/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Supervivencia sin Progresión , Estudios Prospectivos , Temozolomida/administración & dosificación , Temozolomida/efectos adversos , Adulto Joven
6.
BMC Pregnancy Childbirth ; 19(1): 394, 2019 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-31672129

RESUMEN

BACKGROUND: The management of Acute Myeloid Leukemia (AML) during pregnancy remains challenging as both the maternal and fetal outcomes should be considered. Several reports suggested that chemotherapy can be administered safely during the second and third trimester of pregnancy. However, the use of 5-azacytidine presents limitation due to lack of data. CASE PRESENTATION: A 28-years-old woman in the 26th week of gestation diagnosed with FLT3/ITD-mutated AML, complete remission was induced by Daunorubicin and Cytarabine, and subsequently with 5-azacytidine (75 mg/m2 daily for 7 days) with no fetal hematological or toxicity issues. Fetal ultrasound showed no aberrant morphology. Fetal size below the 5th percentile with normal umbilical artery dopplers, normal middle cerebral artery dopplers and ductus venosus doppler. Three weeks post 5-azacytidine, the team determined the most appropriate time for delivery after balancing the risks of prematurity and prevention of disease relapse since patient in hematological remission. The patient underwent elective lower segment caesarian section and had a baby girl delivered at 35 weeks of gestation weighing 1670 g without apparent anomalies. CONCLUSION: Treatment using 5-azacytadine during last trimester of pregnancy resulted in no major fetal and maternal complications. These findings concluded that 5-azacytadine during the third trimester of pregnancy seems to be safe however, potential risks of this agent should be considered.


Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Azacitidina/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Complicaciones Neoplásicas del Embarazo/tratamiento farmacológico , Adulto , Cesárea , Femenino , Humanos , Quimioterapia de Inducción , Recién Nacido , Nacimiento Vivo , Embarazo , Tercer Trimestre del Embarazo
7.
Sensors (Basel) ; 19(13)2019 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-31324070

RESUMEN

According to the survey on various health centres, smart log-based multi access physical monitoring system determines the health conditions of humans and their associated problems present in their lifestyle. At present, deficiency in significant nutrients leads to deterioration of organs, which creates various health problems, particularly for infants, children, and adults. Due to the importance of a multi access physical monitoring system, children and adolescents' physical activities should be continuously monitored for eliminating difficulties in their life using a smart environment system. Nowadays, in real-time necessity on multi access physical monitoring systems, information requirements and the effective diagnosis of health condition is the challenging task in practice. In this research, wearable smart-log patch with Internet of Things (IoT) sensors has been designed and developed with multimedia technology. Further, the data computation in that smart-log patch has been analysed using edge computing on Bayesian deep learning network (EC-BDLN), which helps to infer and identify various physical data collected from the humans in an accurate manner to monitor their physical activities. Then, the efficiency of this wearable IoT system with multimedia technology is evaluated using experimental results and discussed in terms of accuracy, efficiency, mean residual error, delay, and less energy consumption. This state-of-the-art smart-log patch is considered as one of evolutionary research in health checking of multi access physical monitoring systems with multimedia technology.


Asunto(s)
Aprendizaje Profundo , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Dispositivos Electrónicos Vestibles , Algoritmos , Teorema de Bayes , Presión Sanguínea , Temperatura Corporal , Electrocardiografía , Electroencefalografía , Electromiografía , Humanos , Multimedia , Redes Neurales de la Computación
8.
Biochem Biophys Res Commun ; 489(4): 451-454, 2017 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-28571743

RESUMEN

Defined as a state function representing an inhibitor's absolute affinity for its target enzyme, the experimentally determined enzyme inhibition constant (Ki) is widely used to rank order binding affinities of different inhibitors for a common enzyme or different enzymes for a common inhibitor and to benchmark computational approaches to predicting binding affinity. Herein, we report that adsorption of bis(7)-tacrine to the glass container surface increased its Ki against Electrophorus electricus acetylcholinesterase (eeAChE) to 3.2 ± 0.1 nM (n = 5) compared to 2.9 ± 0.4 pM (n = 5) that was determined using plastic containers with other assay conditions kept the same. We also report that, due to binding or "adsorption" of bis(7)-tacrine to the inactive eeAChE, the bis(7)-tacrine Ki increased from 2.9 ± 0.4 pM (n = 5) to 734 ± 70 pM (n = 5) as the specific eeAChE activity decreased from 342 U/mg to 26 U/mg while other assay conditions were kept the same. These results caution against using Kis to rank order binding potencies, define selectivity, or benchmark computational methods without knowing detailed assay conditions.


Asunto(s)
Acetilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/farmacología , Animales , Sitios de Unión/efectos de los fármacos , Inhibidores de la Colinesterasa/química , Anguilas , Unión Proteica/efectos de los fármacos , Relación Estructura-Actividad
9.
J Nanosci Nanotechnol ; 17(4): 2296-301, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29638292

RESUMEN

Here we report development of a hydroquinone (HQ) electrochemical sensor using nanosized manganese doped titanium oxide as a composite material. The nanomaterial was synthesized with sol gel method using calculated amount of Mn and Ti atoms resulting into a composite metal oxide. Morphological observations indicated a uniform particle size and shape distribution with almost spherical shape and size of about 20­30 nm. While structural analysis indicated formation of mixed phase of TiO2 and MnO forming MnTiO3. The synthesized nanomaterial was used as a matrix for fabrication of hydroquinone electrochemical sensor and tested over a wide range from 2 mM to 10 mM. The developed electrochemical sensor exhibited sensitivity of 2.96 µA mM⁻¹ (23.55 µA mM⁻¹ cm⁻²) with a detection limit of 7.5 µM, which is rarely reported for such composite nanomaterial.

10.
Mar Drugs ; 14(8)2016 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-27455287

RESUMEN

An increasing interest has recently been shown to use chitin/chitosan oligomers (chito-oligomers) in medicine and food fields because they are not only water-soluble, nontoxic, and biocompatible materials, but they also exhibit numerous biological properties, including antibacterial, antifungal, and antitumor activities, as well as immuno-enhancing effects on animals. Conventional depolymerization methods of chitosan to chito-oligomers are either chemical by acid-hydrolysis under harsh conditions or by enzymatic degradation. In this work, hydrolysis of chitosan to chito-oligomers has been achieved by applying adsorption-separation technique using diluted HCl in the presence of different types of zeolite as adsorbents. The chito-oligomers were retrieved from adsorbents and characterized by differential scanning calorimetry (DSC), liquid chromatography/mass spectroscopy (LC/MS), and ninhydrin test.


Asunto(s)
Quitina/química , Quitosano/química , Zeolitas/química , Antibacterianos/química , Antifúngicos/química , Antineoplásicos/química , Materiales Biocompatibles/química , Rastreo Diferencial de Calorimetría , Cromatografía Liquida , Ácido Clorhídrico/química , Hidrólisis , Indicadores y Reactivos/química , Espectrometría de Masas , Ninhidrina/química
11.
Mar Drugs ; 13(3): 1519-47, 2015 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-25810109

RESUMEN

Despite the numerous uses of chitin and chitosan as new functional materials of high potential in various fields, they are still behind several directly compressible excipients already dominating pharmaceutical applications. There are, however, new attempts to exploit chitin and chitosan in co-processing techniques that provide a product with potential to act as a direct compression (DC) excipient. This review outlines the compression properties of chitin and chitosan in the context of DC pharmaceutical applications.


Asunto(s)
Quitina/química , Quitosano/química , Excipientes/química , Animales , Química Farmacéutica/métodos , Humanos , Preparaciones Farmacéuticas/administración & dosificación
12.
Andrologia ; 47(6): 616-25, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25059462

RESUMEN

The efficacy of a novel curcumin derivative (NCD) versus tadalafil in erectile signalling was assessed. Ten control male rats and 50 diabetic male rats were used and divided into the following: diabetic (DM), curcumin (CURC), NCD, tadalafil and NCD combined with tadalafil rat groups. Cavernous tissue gene expression of heme oxygenase-1 (HO-1), Nrf2, NF-B and p38, enzyme activities of heme oxygenase (HO) and nitric oxide synthase (NOS), cGMP and intracavernosal pressure (ICP)/mean arterial pressure (MAP) were assessed. Results showed that 12 weeks after induction of diabetes, erectile dysfunction (ED) was confirmed by the significant decrease in ICP/MAP, a significant decrease in cGMP, NOS, HO enzyme activities, a significant decrease in HO-1 gene and a significant increase in NF-Ò ß, p38 genes. Administration of all therapeutic interventions led to a significant increase in ICP/MAP, cGMP levels, a significant increase in HO-1 and NOS enzymes, a significant increase in HO-1, and Nrf2 gene expression, and a significant decrease in NF-Ò ß, p38 gene expression. NCD or its combination with tadalafil showed significant superiority and more prolonged duration of action. In conclusion, a tendency was observed that CURC and NCD have high efficacy and more prolonged duration of action in enhancing erectile function.


Asunto(s)
Curcumina/análogos & derivados , Disfunción Eréctil/tratamiento farmacológico , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Tadalafilo/uso terapéutico , Animales , GMP Cíclico/análisis , Diabetes Mellitus Experimental/complicaciones , Disfunción Eréctil/etiología , Hemo-Oxigenasa 1/metabolismo , Masculino , Factor 2 Relacionado con NF-E2/análisis , FN-kappa B/análisis , Óxido Nítrico Sintasa/metabolismo , Pene/química , Pene/efectos de los fármacos , Pene/enzimología , Ratas , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
13.
Bioorg Med Chem ; 22(17): 4867-81, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25047936

RESUMEN

Selective and nanomolar acetylcholinesterase inhibitors were obtained by connecting tri- and tetracyclic quinazolinones-previously described as moderately active and unselective cholinesterase (ChE) inhibitors-via a hydroxyl group in para position to an anilinic nitrogen with different amines linked via a three carbon atom spacer. These tri- and tetracyclic quinazolinones containing different alicyclic ring sizes and connected to tertiary amines were docked to a high-resolution hAChE crystal structure to investigate the preferred binding mode in relation to results obtained by experimental structure-activity relationships. While the 'classical orientation' locating the heterocycle in the active site was rarely found, an alternative binding mode with the basic aliphatic amine in the active center ('inverted' orientation) was obtained for most compounds. Analyses of extended SARs based on this inverted binding mode are able to explain the compounds' binding affinities at AChE.


Asunto(s)
Acetilcolinesterasa/metabolismo , Aminas/química , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/farmacología , Quinazolinonas/farmacología , Sitios de Unión/efectos de los fármacos , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Quinazolinonas/síntesis química , Quinazolinonas/química , Relación Estructura-Actividad
14.
Bioorg Med Chem ; 22(17): 5020-34, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25059502

RESUMEN

A series of cyclic acyl guanidine with carbamate moieties have been synthesized and evaluated in vitro for their AChE and BChE inhibitory activities. Structure-activity relationships identified compound 23 as a nanomolar and selective BChE inhibitor, while compound 32 exhibited nanomolar and selective AChE inhibition, selectivity depending on both the structure of the carbamate substituent as well as the position of guanidines-N substitution. The velocity of enzyme carbamoylation was analyzed and showed similar behavior to physostigmine. Phenolic compounds formed after carbamate transfer to the active site of cholinesterases showed additional neuroprotective properties on a hippocampal neuronal cell line (HT-22) after glutamate-induced intracellular reactive oxygen species generation.


Asunto(s)
Acetilcolinesterasa/metabolismo , Butirilcolinesterasa/metabolismo , Carbamatos/química , Inhibidores de la Colinesterasa/farmacología , Guanidinas/farmacología , Animales , Butirilcolinesterasa/sangre , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Relación Dosis-Respuesta a Droga , Electrophorus , Guanidinas/síntesis química , Guanidinas/química , Caballos , Estructura Molecular , Relación Estructura-Actividad
15.
Bioorg Med Chem ; 22(15): 3938-46, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24984935

RESUMEN

The design of bivalent ligands targeting G protein-coupled receptors (GPCRs) often leads to the development of new, highly selective and potent compounds. To date, no bivalent ligands for the human cannabinoid receptor type 2 (hCB2R) of the endocannabinoid system (ECS) are described. Therefore, two sets of homobivalent ligands containing as parent structure the hCB2R selective agonist 13a and coupled at different attachment positions were synthesized. Changes of the parent structure at these positions have a crucial effect on the potency and efficacy of the ligands. However, we discovered that bivalency has an influence on the effect at both cannabinoid receptors. Moreover, we found out that the spacer length and the attachment position altered the efficacy of the bivalent ligands at the receptors by turning agonists into antagonists and inverse agonists.


Asunto(s)
Bencimidazoles/química , Receptor Cannabinoide CB2/agonistas , Bencimidazoles/síntesis química , Bencimidazoles/metabolismo , Diseño de Fármacos , Humanos , Cinética , Ligandos , Unión Proteica , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB1/antagonistas & inhibidores , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/antagonistas & inhibidores , Receptor Cannabinoide CB2/metabolismo
16.
Biomed Eng Online ; 13: 125, 2014 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-25168723

RESUMEN

BACKGROUND: High Density Polyethylene (HDPE) is one of the most often used polymers in biomedical applications. The limitations of HDPE are its visco-elastic behavior, low modulus and poor bioactivity. To improve HDPE properties, HA nanoparticles can be added to form polymer composite that can be used as alternatives to metals for bone substitutes and orthopaedic implant applications. METHOD: In our previous work (BioMedical Engineering OnLine 2013), different ratios of HDPE/HA nanocomposites were prepared using melt blending in a co-rotating intermeshing twin screw extruder. The accelerated aging effects on the tensile properties and torsional viscoelastic behavior (storage modulus (G') and Loss modulus (G")) at 80°C of irradiated and non-irradiated HDPE/HA was investigated. Also the thermal behavior of HDPE/HA were studied. In this study, the effects of gamma irradiation on the tensile viscoelastic behavior (storage modulus (E') and Loss modulus (E")) at 25°C examined for HDPE/HA nanocomposites at different frequencies using Dynamic Mechanical Analysis (DMA). The DMA was also used to analyze creep-recovery and relaxation properties of the nanocomposites. To analyze the thermal behavior of the HDPE/HA nanocomposite, Differential Scanning Calorimetry (DSC) was used. RESULTS: The microscopic examination of the cryogenically fractured surface revealed a reasonable distribution of HA nanoparticles in the HDPE matrix. The DMA showed that the tensile storage and loss modulus increases with increasing the HA nanoparticles ratio and the test frequency. The creep-recovery behavior improves with increasing the HA nanoparticle content. Finally, the results indicated that the crystallinity, viscoelastic, creep recovery and relaxation behavior of HDPE nanocomposite improved due to gamma irradiation. CONCLUSION: Based on the experimental results, it is found that prepared HDPE nanocomposite properties improved due to the addition of HA nanoparticles and irradiation. So, the prepared HDPE/HA nanocomposite appears to have fairly good comprehensive properties that make it a good candidate as bone substitute.


Asunto(s)
Sustitutos de Huesos/química , Durapatita/química , Nanocompuestos/química , Nanopartículas/química , Polietileno/química , Materiales Biocompatibles/química , Materiales Biocompatibles/efectos de la radiación , Sustitutos de Huesos/efectos de la radiación , Calorimetría , Durapatita/efectos de la radiación , Rayos gamma , Nanocompuestos/efectos de la radiación , Nanopartículas/efectos de la radiación , Polietileno/efectos de la radiación , Viscosidad
17.
J Mater Sci Mater Med ; 25(4): 1045-53, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24375170

RESUMEN

In the present work, a series of 0, 1 and 7 wt% silver nano-particles (Ag NPs) incorporated poly lactic-co-glycolic acid (PLGA) nano-fibers were synthesized by the electrospinning process. The PLGA/Ag nano-fibers sheets were characterized using SEM, TEM and DSC analyses. The three synthesized PLGA/silver nano-fiber composites were screened for anticancer activity against liver cancer cell line using MTT and LDH assays. The anticancer activity of PLGA nano-fibers showed a remarkable improvement due to increasing the concentration of the Ag NPs. In addition to the given result, PLGA nano-fibers did not show any cytotoxic effect. However, PLGA nano-fibers that contain 1 % nano silver showed anticancer activity of 8.8 %, through increasing the concentration of the nano silver to 7 % onto PLGA nano-fibers, the anticancer activity was enhanced to a 67.6 %. Furthermore, the antibacterial activities of these three nano-fibers, against the five bacteria strains namely; E.coli o157:H7 ATCC 51659, Staphylococcus aureus ATCC 13565, Bacillus cereus EMCC 1080, Listeria monocytogenes EMCC 1875 and Salmonella typhimurium ATCC25566 using the disc diffusion method, were evaluated. Sample with an enhanced inhibitory effect was PLGA/Ag NPs (7 %) which inhibited all strains (inhibition zone diameter 10 mm); PLGA/Ag NPs (1 %) sample inhibited only one strain (B. cereus) with zone diameter 8 mm. The PLGA nano-fiber sample has not shown any antimicrobial activity. Based on the anticancer as well as the antimicrobial results in this study, it can be postulated that: PLGA nanofibers containing 7 % nano silver are suitable as anticancer- and antibiotic-drug delivery systems, as they will increase the anticancer as well as the antibiotic drug potency without cytotoxicity effect on the normal cells. These findings also suggest that Ag NPs, of the size (5-10 nm) evaluated in the present study, are appropriate for therapeutic application from a safety standpoint.


Asunto(s)
Antiinfecciosos/administración & dosificación , Antineoplásicos/administración & dosificación , Materiales Biocompatibles/química , Sistemas de Liberación de Medicamentos , Plata/administración & dosificación , Línea Celular , Técnicas Electroquímicas , Células Hep G2 , Humanos , Ácido Láctico/química , Neoplasias Hepáticas/tratamiento farmacológico , Ensayo de Materiales , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Nanocompuestos/química , Nanocompuestos/ultraestructura , Nanofibras/química , Nanofibras/ultraestructura , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
18.
ScientificWorldJournal ; 2014: 857363, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25374941

RESUMEN

The fruits of four wild plants, namely, Capparis decidua, Ficus carica, Syzygium cumini, and Ziziphus jujuba, are separately used as traditional dietary and remedial agents in remote areas of Khyber Pakhtunkhwa, Pakistan. The results of our study on these four plants revealed that the examined fruits were a valuable source of nutraceuticals and exhibited good level of antimicrobial activity. The fruits of these four investigated plants are promising source of polyphenols, flavonoids, alkaloids, terpenoids, and saponins. These four plants' fruits are good sources of iron, zinc, copper, manganese, selenium, and chromium. It was also observed that these fruits are potential source of antioxidant agent and the possible reason could be that these samples had good amount of phytochemicals. Hence, the proper propagation, conservation, and chemical investigation are recommended so that these fruits should be incorporated for the eradication of food and health related problems.


Asunto(s)
Antibacterianos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Capparis/química , Ficus/química , Syzygium/química , Ziziphus/química , Alcaloides/aislamiento & purificación , Alcaloides/farmacología , Antibacterianos/farmacología , Antioxidantes/farmacología , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/crecimiento & desarrollo , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Cationes Bivalentes , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Frutas/química , Humanos , Metales/análisis , Pruebas de Sensibilidad Microbiana , Polifenoles/aislamiento & purificación , Polifenoles/farmacología , Saponinas/aislamiento & purificación , Saponinas/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Terpenos/aislamiento & purificación , Terpenos/farmacología , Trichophyton/efectos de los fármacos , Trichophyton/crecimiento & desarrollo
19.
Sultan Qaboos Univ Med J ; 24(3): 360-366, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39234330

RESUMEN

Objectives: This study attempted to develop 2 biodegradable periodontal chips containing Salvadora persica (miswak) or benzyl isothiocyanate (BITC) extracts and evaluate their clinical effectiveness in managing periodontitis. Methods: This clinical trial was conducted at the Faculty of Dentistry, Universiti Teknologi MARA Shah Alam, Selangor, Malaysia, from September 2010 to April 2012. Periodontal chips were formulated using S. persica, benzyl isothiocyanate (BITC) and chitosan extracts. All patients were treated with full mouth scaling and root planing at baseline. Thereafter, the periodontal pockets (≥5 mm in length) were divided into 4 groups: the control group; group 2 (plain chitosan chip); group 3 (S. persica extract); and group 4 (BITC extract). Plaque index (PI), bleeding on probing (BOP), periodontal probing pocket depth and clinical attachment levels were recorded at days 0 and 60 only. Results: A total of 12 patients participated in this study. Overall, 240 periodontal pockets were evaluated. The study revealed significant improvements in PI, BOP and reduction in periodontal pocket depth in all 4 groups (P <0.05). The improvement in clinical attachment level was significantly higher (P <0.001) among the group that received S. persica chips compared to the control and other chip-treated groups. Conclusion: Periodontal chips containing S. persica can be used as adjuncts to treat patients with periodontitis.


Asunto(s)
Quitosano , Periodontitis , Extractos Vegetales , Salvadoraceae , Humanos , Quitosano/uso terapéutico , Quitosano/farmacología , Extractos Vegetales/uso terapéutico , Extractos Vegetales/farmacología , Femenino , Masculino , Periodontitis/tratamiento farmacológico , Periodontitis/terapia , Adulto , Malasia , Persona de Mediana Edad , Aplanamiento de la Raíz/métodos , Resultado del Tratamiento , Raspado Dental/métodos
20.
Biomed Eng Online ; 12: 5, 2013 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-23324627

RESUMEN

BACKGROUND: Stress shielding in the cemented hip prosthesis occurs due to the mismatching in the mechanical properties of metallic stem and bone. This mismatching in properties is considered as one of the main reasons for implant loosening. Therefore, a new stem material in orthopedic surgery is still required. In the present study, 3D finite element modeling is used for evaluating the artificial hip joint stem that is made of Function Graded (FG) material in terms of joint stress distributions and stem length. METHOD: 3D finite element models of different stems made of two types of FG materials and traditional stems made of Cobalt Chromium alloy (CoCrMo) and Titanium alloy (Ti) were developed using the ANSYS Code. The effects on the total artificial hip joint stresses (Shear stress and Von Mises stresses at bone cement, Von Mises stresses at bone and stem) due to using the proposed FG materials stems were investigated. The effects on the total artificial hip joint system stresses due to using different stem lengths were investigated. RESULTS: Using FG stem (with low stiffness at stem distal end and high stiffness at its proximal end) resulted in a significant reduction in shear stress at the bone cement/stem interface. Also, the Von Mises stresses at the bone cement and stem decrease significantly when using FG material instead of CoCrMo and Ti alloy. The stresses' distribution along the bone cement length when using FG material was found to be more uniform along the whole bone cement compared with other stem materials. These more uniform stresses will help in the reduction of the artificial hip joint loosening rate and improve its short and long term performance. CONCLUSION: FE results showed that using FG stem increases the resultant stresses at the femur bone (reduces stress shielding) compared to metallic stem. The results showed that the stem length has significant effects on the resultant shear and Von Mises stresses at bone, stem and bone cement for all types of stem materials.


Asunto(s)
Cementos para Huesos , Análisis de Elementos Finitos , Articulación de la Cadera/fisiología , Prótesis de Cadera , Estrés Mecánico , Artroplastia de Reemplazo de Cadera , Materiales Biocompatibles , Fenómenos Biomecánicos , Aleaciones de Cromo/química , Simulación por Computador , Humanos , Titanio/química
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