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1.
AAPS PharmSciTech ; 25(1): 18, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38263347

RESUMEN

Due to tenoxicam (TX)'s poor aqueous solubility (0.072 mg/ml), it is poorly absorbable in the GIT, and the long-term oral administration of TX may cause severe GIT disturbances. Topical administration of TX can help in bypassing the GIT adverse effects. Therefore, in the present work, we constructed different pluronic/lecithin organogels (PLOs) for topical delivery of TX. PLO was constructed simply via direct mixing of an aqueous pluronic solution with lecithin solution. The prepared PLO formulations were characterized for their physicochemical properties including pH, drug content, visual inspection, viscosity, and spreadability. Also, the in vitro release and kinetic studies were carried out to investigate the mechanism of drug release. Moreover, the in vivo studies were carried out by investigating the anti-inflammatory and analgesic activities using albino male rats. The results showed that the modified PLOs have good physicochemical properties. The viscosity of the modified gels is a direct proportionality with both lecithin and pluronic concentrations. Also, subsequently, the drug release rate is directly proportional to gel viscosity. Moreover, the in vivo studies showed that the modified PLOs (F19) showed a significant ( < 0.05%) paw edema inhibition and pain analgesia compared with other investigated groups. Also, the results indicated that the increase in dose is accompanied by higher activity and a longer duration of action which extended to 12 h. Hence, the modified PLOs are promising safe candidates or vehicles for effective TX loading with sustained delivery behavior.


Asunto(s)
Lecitinas , Piroxicam/análogos & derivados , Poloxámero , Animales , Ratas , Cinética , Inflamación , Dolor
2.
Int J Biol Macromol ; 246: 125638, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37392910

RESUMEN

Due to its poor solubility and systemic side effects, gefitinib (Gef) has limited application in treatment of lung cancer. In this study, we used design of experiment (DOE) tools to gain the necessary knowledge for the synthesis of high-quality gefitinib loaded chitosan nanoparticles (Gef-CSNPs) capable of delivering and concentrating Gef at A549 cells, thereby increasing therapeutic effectiveness while decreasing adverse effects. The optimized Gef-CSNPs were characterized by SEM, TEM, DSC, XRD, and FTIR analyses. The optimized Gef-CSNPs had a particle size of 158±3.6 nm, an entrapment efficiency of 93±1.2 %, and a release of 97±0.6 % after 8 h. The in vitro cytotoxicity of the optimized Gef-CSNPs was found to be significantly higher than pure Gef (IC50 = 10.08 ± 0.76 µg/mL and IC50 = 21.65 ± 0.32 µg/mL), respectively. In the A549 human cell line, the optimized Gef-CSNPs formula outperformed pure Gef in terms of cellular uptake (3.286 ± 0.12 µg/mL and 1.777 ± 0.1 µg/mL) and apoptotic population (64.82 ± 1.25 % and 29.38 ± 1.11 %), respectively. These findings explain why researchers are so interested in using natural biopolymers to combat lung cancer, and they paint an optimistic picture of their potential as a promising tool in the fight against lung cancer.

3.
Int J Nanomedicine ; 18: 3247-3281, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37337575

RESUMEN

The real problem in pharmaceutical preparation is drugs' poor aqueous solubility, low permeability through biological membranes, and short biological t1/2. Conventional drug delivery systems are not able to overcome these problems. However, cyclodextrins (CDs) and their derivatives can solve these challenges. This article aims to summarize and review the history, properties, and different applications of cyclodextrins, especially the ability of inclusion complex formation. It also refers to the effects of cyclodextrin on drug solubility, bioavailability, and stability. Moreover, it focuses on preparing and applying gold nanoparticles (AuNPs) as novel drug delivery systems. It also studies the uses and effects of cyclodextrins in this field as novel drug carriers and targeting devices. The system formulated from AuNPs linked with CD molecules combines the advantages of both CD and AuNPs. Cyclodextrins benefit in increasing aqueous drug solubility, loading capacity, stability, and size control of gold NPs. Also, AuNPs are applied as diagnostic and therapeutic agents because of their unique chemical properties. Plus, AuNPs possess several advantages such as ease of detection, targeted and selective drug delivery, greater surface area, high loading efficiency, and higher stability than microparticles. In the present article, we tried to present the potential pharmaceutical applications of CD-derived AuNPs in biomedical applications including antibacterial, anticancer, gene-drug delivery, and various targeted drug delivery applications. Also, the article highlighted the role of CDs in the preparation and improvement of catalytic enzymes, the formation of self-assembling molecular print boards, the fabrication of supramolecular functionalized electrodes, and biosensors formation.


Asunto(s)
Ciclodextrinas , Nanopartículas del Metal , Preparaciones Farmacéuticas , Ciclodextrinas/química , Oro , Sistemas de Liberación de Medicamentos , Portadores de Fármacos/química
4.
Gels ; 9(4)2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-37102938

RESUMEN

Breast cancer is the second most common cancer in women worldwide. Long-term treatment with conventional chemotherapy may result in severe systemic side effects. Therefore, the localized delivery of chemotherapy helps to overcome such a problem. In this article, self-assembling hydrogels were constructed via inclusion complexation between host ß-cyclodextrin polymers (8armPEG20k-CD and pß-CD) and the guest polymers 8-armed poly(ethylene glycol) capped either with cholesterol (8armPEG20k-chol) or adamantane (8armPEG20k-Ad) and were loaded with 5-fluorouracil (5-FU) and methotrexate (MTX). The prepared hydrogels were characterized by SEM and rheological behaviors. The in vitro release of 5-FU and MTX was studied. The cytotoxicity of our modified systems was investigated against breast tumor cells (MCF-7) using an MTT assay. Additionally, the histopathological changes in breast tissues were monitored before and after their intratumor injection. The results of rheological characterization indicated the viscoelastic behavior in all cases except for 8armPEG-Ad. In vitro release results showed a variable range of release profiles from 6 to 21 days, depending on the hydrogel composition. MTT findings indicated the inhibition ability of our systems against the viability of cancer cells depending on the kind and concentration of the hydrogel and the incubation period. Moreover, the results of histopathology showed the improvement of cancer manifestation (swelling and inflammation) after intratumor injection of loaded hydrogel systems. In conclusion, the obtained results indicated the applicability of the modified hydrogels as injectable vehicles for both loading and controlled release of anticancer therapies.

5.
ACS Omega ; 8(9): 8488-8496, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36910957

RESUMEN

Catalytic hydrogenation is one of the most important reaction types commonly used in chemistry and chemical industry. Recently, there has been significant interest in developing a metal-free hydrogenation catalyst to avoid the problems caused by using heavy transition metal catalysts. On the basis of the advances of metal-free hydrogen activation with frustrated Lewis pairs (FLPs, e.g. tBu3P/B(C6F5)3) which often uses boron as a Lewis acid center, we computationally explored the prospect for phosphorus(V) and sulfur(VI) as Lewis acid centers to construct FLPs for hydrogen activation and hydrogenation. We found out that the proposed FLPs with P(V)- or S(VI)-centered Lewis acid can also activate H2 with a mechanism similar to that used by the conventional FLPs. A heterolytic cleavage of H-H is achieved when electrons are donated simultaneously from the σ orbital of H2 to the empty orbital of the Lewis acid center and from the lone-pair orbital of the Lewis base center to the σ* orbital of H2. The multiple C-H···F hydrogen bonds further aid the association of the pairs for H2 activation. Some of our designed FLPs possess kinetics and thermodynamics for developing hydrogenation catalysts. This computational exploration could inspire experimental development of a new type of FLPs with P(V) or S(VI) or a Lewis acid partner for FLPs for reversible H2 activation.

6.
Front Pharmacol ; 14: 1025013, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36825154

RESUMEN

The purpose of this study was to assess the parameters of doxorubicin (DOX) loaded lipid polymer hybrid nanoparticles (LPHNs) formulation development, and then the bioavailability of DOX were determined in the rabbit model, in order to evaluate the intrinsic outcome of dosage form improvement after the oral administration. LPHNs were prepared by combine approach, using both magnetic stirring and probe sonication followed by its characterization in terms of size-distribution (Zeta Size), entrapment efficiency (EE), loading capacity, and the kinetics of DOX. LPHNPs were further characterized by using scanning electron microscopy (SEM), powder X-Ray diffractometry (P-XRD), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), in vitro and in vivo studies. The molecular modeling was determined through the density functional theory (DFT) simulations and interactions. DOX loaded and unloaded LPHNs were administered orally to the rabbits for bioavailability and pharmacokinetic parameters determinations. The plasma concentration of DOX was determined through high performance liquid chromatography (HPLC). The average size of DOX-loaded LPHNs was 121.90 ± 3.0 nm. The drug loading of DOX was 0.391% ± 0.01 of aqueous dispersion, where its encapsulation efficiency was 95.5% ± 1.39. After oral administration of the DOX-LPHNs, the area under the plasma drug concentration-time curve (AUC) improved about 2-folds comparatively (p < 0.05). DFT simulations were used to understand the interactions of polymers with different sites of DOX molecule. The larger negative binding energies (-9.33 to -18.53 kcal/mol) of the different complexes evince that the polymers have stronger affinity to bind with the DOX molecule while the negative values shows that the process is spontaneous, and the synthesis of DOX-LPHNs is energetically favorable. It was concluded that DOX-LPHNs provides a promising new formulation that can enhance the oral bioavailability, which have optimized compatibilities and improve the pharmacokinetic of DOX after oral administration.

7.
Artículo en Inglés | MEDLINE | ID: mdl-36767569

RESUMEN

Adequate access to drinking water for hydration and hygiene depends on many factors. We developed the Drinking Water Security Index (DWSI) to assess relative multifactorial drinking water security at different spatial and temporal scales. DWSI is a function of four key indicators of drinking water security: water quality, water accessibility, water continuity, and water availability. We built DWSI with a total of 10 variables and applied the new index in Sudan to assess historical and future drinking water security at state, local, and maternity levels. Analyses at the state level found that the Red Sea and River Nile states are most vulnerable, with the lowest DWSI for both historical and future periods. The 1 km2 pixel level analysis shows large differences in water security within the major states. Analyses at the maternity level showed that nearly 18.97 million people are affected by the 10% of maternities with the lowest DWSI, a number projected to increase by 60% by 2030. Current and future DWSI of maternities providing Emergency Obstetric and Newborn Care was assessed to identify those where urgent action is needed to ensure quality health care in water-secure conditions. This work provides useful information for stakeholders in the health and drinking water sectors in Sudan, to improve public health, reduce preventable mortality, and make the population more resilient to projected environmental changes.


Asunto(s)
Agua Potable , Abastecimiento de Agua , Embarazo , Recién Nacido , Humanos , Femenino , Sudán , Calidad del Agua , Salud Pública
8.
Saudi Pharm J ; 31(1): 29-54, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36685309

RESUMEN

Lung cancer is the number one killer among all cancer types. For decades, clinicians have been using conventional chemotherapeutics, but they can't rely on them alone anymore, because they poison bad cells and good cells as well. Researchers exploited nanotechnology as a potential tool to develop a platform for drug delivery to improve therapeutic efficiency. A quality by design synthesis of gefitinib-loaded starch nanoparticles (Gef-StNPs) has emerged as an essential tool to study and optimize the factors included in their synthesis. Therefore, we applied design of experiment (DOE) tools to attain the essential knowledge for the synthesis of high-quality Gef-StNPs that can deliver and concentrate the gefitinib (Gef) at A549 cells, thereby improving therapeutic efficacy and minimizing adverse effects. The in vitro cytotoxicity after exposing the A549 human lung cancer cells to the optimized Gef-StNPs was found to be much higher than that of the pure Gef (IC50 = 6.037 ± 0.24 and 21.65 ± 0.32 µg/mL, respectively). The optimized Gef-StNPs formula showed superiority over the pure Gef regarding the cellular uptake in A549 human cell line (3.976 ± 0.14 and 1.777 ± 0.1 µg/mL) and apoptotic population (77.14 ± 1.43 and 29.38 ± 1.11 %), respectively. The results elucidate why researchers have a voracious appetite for using natural biopolymers to combat lung cancer and paint an optimistic picture of their potential to be a promising tool in battling lung cancer.

9.
AAPS PharmSciTech ; 24(1): 44, 2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36703092

RESUMEN

Tenoxicam (TX) is a non-steroidal anti-inflammatory agent that can be used to control pain in various ophthalmic lesions like cataracts, refractive surgery, and corneal abrasion. TX has a very slightly aqueous solubility of 0.072 mg/mL resulting in difficulty to be formulated in ophthalmic solutions. This study aims to improve TX solubility by converting it into its potassium salt to achieve a target of 10 mg/mL (1%w/v) concentration of TX in the desired aqueous medium for the formulation of aqueous ophthalmic solutions. The synthesized TX salt was characterized by different evaluation parameters such as solubility studies, 1H NMR, IR, and elemental analyses. Different TX potassium solutions were formulated at concentrations of 0.5% and 1% w/v using different viscosity-imparting agents. The prepared solutions were characterized for their physicochemical properties including visual inspection, pH, rheological, in vitro release, and kinetic behavior. Also, the formulations were biologically evaluated in vivo using male albino rabbits. The obtained results showed the successful synthesis of TX salt, as indicated by IR and NMR, and elemental analysis. The solubility study showed that the solubility of TX was improved hugely to 18 mg/mL (250-fold). In addition, the results showed that the prepared formulations showed acceptable physicochemical properties. The highest release rate was obtained with formula F1, which contains no viscosity-imparting agents. While as, the lowest release rate was obtained in the case of formula F9, composed of Pluronic F127 (12% w/v). The in vivo results showed that TX optimized ophthalmic solutions F8 and F9 inhibited the redness and edema in an extended or sustained manner.


Asunto(s)
Sistemas de Liberación de Medicamentos , Piroxicam , Animales , Masculino , Conejos , Sistemas de Liberación de Medicamentos/métodos , Antiinflamatorios no Esteroideos , Soluciones Oftálmicas
10.
Cureus ; 15(12): e51296, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38283494

RESUMEN

Single-anastomosis sleeve jejunal (SASJ) bypass is a bariatric surgery technique with promising results. However, evidence of its efficacy and safety is still lacking. This study aimed to summarize the evidence regarding the efficacy and safety of SASJ bypass surgery in the treatment of morbid obesity. The literature was searched for English-language studies published from inception till November 26, 2023, on MEDLINE/PubMed, Cochrane Library, Web of Science, ProQuest, Scopus, SCINAPSE, and Google Scholar. The search terms included "morbid obesity," "bariatric surgery," and "single anastomosis sleeve jejunal bypass." Extracted data included the body mass index (BMI) before and after surgery, percent total weight loss (%TWL), percent excess weight loss (%EWL), and improvement in preoperative comorbidities. Pooling of the data was done using random effects or fixed-effect models based on the presence of significant heterogeneity. Nine studies were included in this systematic review and meta-analysis. The change in BMI from baseline at 12 months after SASJ bypass was significant (standardized mean difference (SMD) = -3.576, 95% confidence interval (CI) = -5.423, -1.730; I² = 99.23%). At 12 months after surgery, the pooled %TWL was 42.526 (95% CI = 37.948, 47.105; I² = 97.15%), and the pooled %EWL was 75.258 (95% CI = 67.061, 83.456; I² = 99.26%). The pooled incidence of postoperative improvement in diabetes mellitus was 91% (95% CI = 79.6%, 98%, I² = 82%). The overall rate of complications was 9.9% (95% CI = 2.5%, 21.6%; I² = 92.64%). Regarding the short- and mid-term outcomes, SASJ bypass is a safe and effective procedure for weight loss in patients with morbid obesity, with an acceptable rate of complications. The procedure is also associated with a marked improvement in obesity-related comorbidities.

11.
Pharmaceutics ; 14(3)2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35336035

RESUMEN

The treatment of breast cancer requires long chemotherapy management, which is accompanied by severe side effects. Localized delivery of anticancer drugs helps to increase the drug concentration at the site of action and overcome such a problem. In the present study, chitosan hydrogel was prepared for local delivery of 5-Fluorouracil. The in vitro release behavior was investigated and the anticancer activity was evaluated against MCF-7 cells using MTT assay. The in vivo studies were investigated via intra-tumoral injection of a 5-FU loaded hydrogel into breast cancer of female rats. The results indicated that the modified hydrogel has excellent physicochemical properties with a sustained in vitro release profile matching a zero-order kinetic for one month. In addition, the hydrogel showed superior inhibition of cell viability compared with the untreated control group. Moreover, the in vivo studies resulted in antitumor activity with minor side effects. The tumor volume and level of tumor markers in blood were inhibited significantly by applying the hydrogel compared with the untreated control group. In conclusion, the designed injectable hydrogels are potential drug delivery systems for the treatment of breast cancer with a controlled drug release profile, which could be suitable for decreasing the side effects of chemotherapy agents.

12.
AAPS PharmSciTech ; 23(1): 45, 2022 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-34981280

RESUMEN

Topical formulation of non-steroidal anti-inflammatory drugs (NSAIDs) exhibits many advantages over the oral administration route, such as avoiding the direct effect on GIT and avoiding the poor oral bioavailability of such drugs. Our study aims to develop a new self-assembling construct based on the hydrophobic interaction between adamantane terminated poly (ethylene glycol) polymers and polymerized ß-cyclodextrin. The viscous constructs were developed from direct mixing of host and guest polymer solutions, indicating spontaneous formation without cross-linkers. The modified system was evaluated by different analyses, including X-ray diffractometry, electron microscopy, isothermal titration calorimetry, and rheological analysis. Moreover, such a system's ability for drug loading and release was investigated via the in vitro release of ketorolac tromethamine (KT) as a model of NSAIDs. Finally, the prepared formulas were applied on a rat paw edema model to prove the enhanced anti-inflammatory activities. The obtained results indicated that the modified constructs have a rubbery porous structure with an amorphous nature. Also, from rheological results, the modified system exhibited a viscous behavior with higher loss modulus (G″) compared with storage (G'). The inclusion complexation between cyclodextrin and adamantane moieties was proved by the recorded high binding constants with a 1:1 stoichiometric ratio. Furthermore, the results showed the successful KT incorporation into the modified system and quantitatively released through a semi-permeable membrane in a sustained fashion (over 24 h). Finally, the in vivo results of the medicated constructs showed a significant inhibition of the induced inflammation and swelling, indicating that the modified construct has a great utility for safe non-irritating topical delivery applications.


Asunto(s)
Adamantano , Ciclodextrinas , Animales , Hidrogeles , Ketorolaco Trometamina , Polietilenglicoles , Ratas
13.
J Med Entomol ; 58(6): 2177-2185, 2021 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-34197598

RESUMEN

Culex quinquefasciatus, a member of the Culex pipiens complex, is widespread in Saudi Arabia and other parts of the world. It is a vector for lymphatic filariasis, Rift Valley fever, and West Nile virus. Studies have shown the deleterious effect of RNA interference (RNAi)-mediated knockdown of various lethal genes in model and agricultural pest insects. RNAi was proposed as a tool for mosquito control with a focus on Aedes aegypti and Anopheles gambiae. In this study, we examined the effect of RNAi of selected target genes on both larval mortality and adult emergence of Cx. quinquefasciatus through two delivery methods: soaking and nanoparticles. Ten candidate genes were selected for RNAi based on their known lethal effect in other insects. Disruption of three genes, chitin synthase-1, inhibitor of apoptosis 1, and vacuolar adenosine triphosphatase, resulted in the highest mortality among the selected genes using the two treatment methods. Silencing the other seven genes resulted in a medium to low mortality in both assays. These three genes are also active against a wide range of insects and could be used for RNAi-based mosquito control in the future.


Asunto(s)
Culex/genética , Control de Mosquitos , Animales , Culex/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Longevidad , Mosquitos Vectores/genética , Mosquitos Vectores/crecimiento & desarrollo , Interferencia de ARN
14.
Minerva Anestesiol ; 87(7): 786-793, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33938674

RESUMEN

BACKGROUND: This study investigated the effect of preoperative ultrasound (US) guided stellate ganglion block (SGB) with bupivacaine on the frequency of post mastectomy pain syndrome (PMPS). METHODS: Eighty patients scheduled for mastectomy with axillary dissection for breast cancer were included in this randomized controlled trial. Patients were randomized into two equal groups: Group A received US guided SGB one hour before surgery using five mL of 0.5% bupivacaine and multimodal systemic analgesia, Group B (control) received multimodal systemic analgesia only. Patients were followed up for six months. PMPS was assessed using the grading system for neuropathic pain (GSNP). Postoperative opioid consumption in the first 24 hours and numeric rating scale (NRS) were documented. Patient daily activity and functional capacity were evaluated using the Eastern Cooperative Oncology Group (ECOG) score. RESULTS: PMPS proportion was significantly lower in group A than group B (30% vs. 62.5%, P=0.004; 52% decrease [95% CI: 18.4%-71.8%]). Postoperative opioid consumption and NRS were significantly lower in group A as compared to group B. ECOG score was significantly higher in Group A than Group B. CONCLUSIONS: Following mastectomy with axillary dissection, preoperative US guided SGB is associated with less PMPS proportion, postoperative pain and opioid consumption and better patient daily activity and functional capacity.


Asunto(s)
Neoplasias de la Mama , Bloqueo Nervioso , Analgésicos Opioides , Anestésicos Locales , Neoplasias de la Mama/cirugía , Método Doble Ciego , Femenino , Humanos , Mastectomía , Dolor Postoperatorio/tratamiento farmacológico , Ganglio Estrellado
15.
AAPS PharmSciTech ; 21(4): 131, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32405869

RESUMEN

5-Fluorouracil is a member of cytotoxic drugs with poor selectivity to cancer cells. Currently, systemic administration of this anti-cancer drug (oral or injection) exposes normal tissues to the drug-induced toxicity. Nowadays, attention has been greatly directed towards in situ gel-forming systems that can be injected into the affected tissues in its sol form with a minimally invasive technique. More specifically, chitosan hydrogel systems were in focus due to their antibacterial effect as well as their biodegradable, biocompatible, and mucoadhesive properties. In the present work, 5-fluorouracil was loaded on various thermosensitive chitosan hydrogel systems cross linked with different linking agents like ß-glycerophosphate, pluronic F127, and hydroxyapatite. Also, methotrexate was added to 5-fluorouracil in order to gain its previously reported synergistic effects. Firstly, a compatibility study was performed using UV-spectrophotometric, infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) techniques to exclude the possibility of any physical or chemical interactions between the selected drugs and excipients. The prepared hydrogel systems were characterized for their physicochemical properties including organoleptic, pH, syringeability and injectability, viscosity, and gelation temperature (Tgel) by various analysis techniques. Moreover, the in vitro release behavior of 5-fluorouracil and methotrexate was determined with a modified analytical method. The results indicated that chitosan hydrogel system cross-linked with a combination of ß- glycerophosphate, and 10 % pluronicF127 (F4) showed the most suitable physicochemical properties and release profile. Accordingly, this formula can be considered as a missionary system for localized sustained delivery of cytotoxic drugs.


Asunto(s)
Quitosano/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Fluorouracilo/metabolismo , Hidrogeles/metabolismo , Metotrexato/metabolismo , Antimetabolitos Antineoplásicos/química , Antimetabolitos Antineoplásicos/metabolismo , Rastreo Diferencial de Calorimetría/métodos , Quitosano/química , Hidrogeles/química , Temperatura
16.
BMC Chem ; 14(1): 36, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32426756

RESUMEN

BACKGROUND: The fatty acids of green coffee beans are one of the major components that determine the quality of coffee. Fatty acids composition of green coffee beans is affected by soil composition and altitude of coffee plants. This study was aimed to evaluate the effect of altitude of the coffee plants on the composition of fatty acids in green coffee beans. METHODS: Fatty acids contents of 40 green coffee beans samples collected from the coffee plants grown at different altitudes (group 1: 1500-1700, group 2: 1701-1900 and group 3: > 1900 m.a.s.l.) in Ethiopia were determined using gas chromatography-mass spectrometry (GC-MS). Chemometric data analyses were performed to determine the effects of altitude on the fatty acid composition of the green coffee beans. RESULTS: The green coffee beans contained main saturated fatty acid, palmitic acid with an average value of 55.5 mg/g and unsaturated fatty acid, linoleic acid with an average value of 51.6 mg/g. The other major constituents of fatty acids present in green coffee beans were stearic and oleic acids with the value of 12.3 mg/g and 8.92 mg/g, respectively. Palmitic acid content in lowland green coffee beans is significantly different than in the other two regions. On the other hand, stearic and oleic acids contents in the green coffee beans did not show a significant difference between the three topographical regions. While linoleic acid content in the green coffee beans showed significant difference between group 1 and 3 but did not show significant differences between group 1 and 2 and between group 2 and 3. The four major fatty acids, palmitic (R = - 0.574), linoleic (R = - 0.506), stearic (R = - 0.43) and oleic acids (R = - 0.291) in green coffee beans showed a moderate negative correlation with the altitude of coffee plants. CONCLUSION: The fatty acids contents decreases with increasing altitude of the coffee plants and hence affects the quality of coffee. The fatty acid composition of green coffee beans can also be used to determine the topographical origin of coffee plants.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 189: 601-607, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-28886506

RESUMEN

We present the absorption and fluorescence spectra of (E)-N-(4-(dimethylamino)benzylidene)-2H-1,2,4-triazol-3-amine (DMABA-Amtr), an electron donor-π-acceptor system. The molecule shows a single fluorescence emission band in non-polar solvents while dual emissions were observed in polar aprotic solvents. Although several researchers over the years provide different explanations for the mechanism of the phenomena, based on solvent assisted excited state geometry changes of such systems, it is still a matter of controversy since such systems are unique as they contradict Kasha's rule. The emission spectrum of the molecule shows strong dependence on solvent polarity and excitation wavelength. This observation together with a single iso-emissive point found in the area normalize emission spectra indicates the presence of two ground state equilibrium structures of the compound which are both fluorescent. Density functional theory (DFT) and time-dependent (TD-DFT) calculations also support the experimental findings.

18.
Sci Rep ; 7(1): 9502, 2017 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-28842624

RESUMEN

Chitin is a major component of insect exoskeleton, tracheal system and gut where it is synthesized by chitin synthase (CHS) enzymes. In this paper, we report the isolation and RNAi of chitin synthase A (PhoCHSA) from the potato tuber moth Phthorimaea operculella. The full-length cDNA of PhoCHSA is 5,627 bp with 4,689 bp open reading frame coding for 1,563 amino acids. Structural analysis of conceptual amino acid translation showed three distinct regions found in all known insect CHS proteins; N-terminus region having 9 transmembrane helices, middle catalytic region containing several conserved domains identified in insect CHS enzymes, and C-terminus region containing seven transmembrane spans. Phylogenetic analysis showed that PhoCHSA protein clustered with CHSA enzymes identified from insects from different insect orders. RNAi targeting three different regions of the gene showed different efficacy against potato tuber moth larvae and dsRNA targeting the 5' region has the highest efficacy. Results were verified by qRT-PCR which showed that dsRNA targeting the 5' region caused the highest reduction in PhoCHSA mRNA level. Our results show the importance of selecting the RNAi target region and that chitin synthase A can be a suitable RNAi target for the potato tuber moth control.


Asunto(s)
Quitina Sintasa/genética , Técnicas de Silenciamiento del Gen , Mariposas Nocturnas/genética , Interferencia de ARN , ARN Interferente Pequeño/genética , Secuencia de Aminoácidos , Animales , Clonación Molecular , Fenotipo , Filogenia , ARN Bicatenario , Análisis de Secuencia de ADN
19.
Surg Laparosc Endosc Percutan Tech ; 27(4): e53-e56, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28614168

RESUMEN

AIM: Transanal minimal invasive surgery has been practiced for several years for excision of rectal tumors however there is no standard consensus about its applications. This minimally invasive approach helps in avoiding major rectal resections and its associated risk of mortality and morbidity.The aim of this study is to describe a single center experience with transanal glove port excision of rectal tumors which are not amenable to colonoscopic excision. MATERIALS AND METHODS: Between the years 2011 and 2014, 9 patients underwent glove port excision of rectal tumors located within 15 cm from the anal verge. Glove port was constructed using circular anal dilator, standard surgical glove and a wound protector retractor; regular laparoscopic instruments were used. The median follow-up period was for 18 months (range, 9 to 27 mo) and all patients had flexible sigmoidoscopy for follow-up to look for any recurrence of the tumors. RESULTS: All patients underwent transanal excision of rectal tumors successfully using glove port device and laparoscopic instruments. Full thickness excision of the tumor was performed in all patients and there was no significant postoperative morbidity. The final histology of 6 patients was benign and the remaining 3 patients had malignancy reported in the specimen. During the follow-up period between 12 and 18 months 3 patients had a recurrence of the polyp which was removed endoscopically without the need for any further surgical intervention. CONCLUSIONS: Glove port excision of rectal tumors is a feasible alternative to conventional surgical treatment for large benign rectal tumors.What does this paper add to the literature?This article demonstrates that performing local excision of rectal tumors can be achieved safely at a lower cost using simple platforms that are constructed locally like the glove ports. It also highlights the benefits of using the available laparoscopic kits to perform the procedure while making use of the previously acquired skills.


Asunto(s)
Laparoscopía/métodos , Neoplasias del Recto/cirugía , Anciano , Dilatación/métodos , Estudios de Factibilidad , Femenino , Humanos , Tiempo de Internación , Masculino , Neoplasias del Recto/patología , Estudios Retrospectivos , Carga Tumoral
20.
Int J Med Educ ; 7: 181-7, 2016 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-27289331

RESUMEN

OBJECTIVE: To compare the Problem-based learning (PBL) with the traditional lecture-based curricula. METHODS: The single best answer Multiple Choice Questions (MCQ) and the Objective Structured Clinical Examination (OSCE) were used to compare performance of the lecture-based curriculum with the PBL medical student groups. The reliability for the MCQs and OSCE was calculated with Kuder-Richardson formula and Cronbach's alpha, respectively. The content validity of the MCQs and OSCE were tested by the Independent Subject Experts (ISE). The Student's t-test for independent samples was used to compare the item difficulty of the MCQs and OSCE's, and the Chi-square test was used to compare the grades between the two student groups. RESULTS: The PBL students outperformed the old curriculum students in overall grades, theoretical knowledge base (tested with K2 type MCQs) and OSCE. The number of the PBL students with scores between 80-90% (grade B) was significantly (p=0.035) higher while their number with scores between 60 to 69% (grade C) was significantly p=0.001) lower than the old curriculum students. Similarly, the mean MCQ and the OSCE scores of the new curriculum students were significantly higher (p = 0.001 and p = 0.025, respectively) than the old curriculum students. Lastly, the old curriculum students found the K2-MCQs to be more (p = 0.001) difficult than the single correct answer (K1 type) MCQs while no such difference was found by the new curriculum students. CONCLUSIONS: Suitably designed MCQs can be used to tap the higher cognitive knowledge base acquired in the PBL setting.


Asunto(s)
Curriculum , Educación Médica/métodos , Aprendizaje Basado en Problemas , Estudiantes de Medicina , Evaluación Educacional , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Kuwait , Masculino , Reproducibilidad de los Resultados
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