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1.
Front Pharmacol ; 15: 1332184, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38595924

RESUMO

Tyrosinase (TYR) inhibitors are very significant as they inhibit enzyme tyrosinase activity, and its inhibition is vital for skin care, anticancer medication, and antibrowning of fruits and vegetables. This work presents a novel and economical route for the preparation of new synthetic tyrosinase inhibitors using amlodipine (4). The novel conjugates 6 (a-o) were designed, synthesized, and characterized by spectroscopic analyses, including Fourier transform infrared and low- and high-resolution mass spectroscopy. The purified compound 4 was refluxed with various aldehydes and ketones 5 (a-o) for 5-8 h in methanol at 60°C-90°C. This research modified the drug in a step-by-step manner to develop therapeutic properties as a tyrosinase inhibitor. The structures of synthesized ligands 6 (a-o) were established based on spectral and analytical data. The synthesized compounds 6 (a-o) were screened against tyrosinase enzyme. Kojic acid was taken as standard. All the prepared compounds 6 (a-o) have good inhibition potential against the enzyme tyrosinase. Compounds 6o, 6b, 6f, and 6k depicted excellent antityrosinase activity. Compound 6k, with an IC50 value of 5.34 ± 0.58 µM, is as potent as the standard kojic acid (IC50 6.04 ± 0.11 µM), standing out among all synthesized compounds 6 (a-o). The in silico studies of the conjugates 6 (a-o) were evaluated via PatchDock. Compound 6k showed a binding affinity score of 8,999 and an atomic contact energy (ACE) value of -219.66 kcal/mol. The structure-activity relationship illustrated that the presence of dihydropyridine nuclei and some activating groups at the ortho and para positions of the benzylideneimine moiety is the main factor for good tyrosinase activity. The compound 6k could be used as a lead compound for drug modification as a tyrosinase inhibitor for skin care, anticancer medication, and antibrowning for fruits and vegetables.

2.
Plants (Basel) ; 11(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35631704

RESUMO

Cotton (Gossypium hirsutum) is a global cash crop which has gained importance in earning foreign exchange for each country. Bacterial blight caused by Xanthomonascitri subsp. malvacearum (Xcm) has been a seriousdisease in Pakistan's cotton belt on multiple occasions. Bacterium was isolated and identified through various biochemical and diagnostic tests wherehypersensitivity reaction, Gram staining, KOH (potassium hydroxide), catalase, starch hydrolysis, lecithinase and Tween 80 hydrolysis tests confirmed bacterium as Gram-negative and plant pathogenic. Xcm perpetuation assays wereevaluated on various cotton varieties under glasshouse conditions in completely randomized design by three different methods, wherein the scratch method proved to be the best upon CIM-496 and showed 83.33% disease incidence as compared with the other two methods, where Bt-3701 responded with 53.33% incidence via the spray gun method, and 50% with the water splash method on CIM-616, as compared with the control. Similarly, for disease severity percentage, Bt-3701 was pragmatic with 47.21% through scratch method, whereas, in the spray gun method, 45.51% disease severity was noted upon Bt-802, and 31.27% was calculated on Cyto-179 through the water splash method. Owing to the unique antibacterial properties of aqueous plant extracts, the poison food technique showed Aloe vera, Mentha piperita, Syzygiumcumini and Azadirachta indica with 17.77, 29.33, 18.33 and 20.22 bacterial colonies counted on nutrient agarmedium petri plate, respectively, as compared with the control. Measurement of the inhibition zone by disk diffusion technique showed Mentha piperita, Syzygiumcumini, Citrus limon, Moringa oleifera and Syzygium aromaticum to present the most promising results by calculating the maximum diameter of the inhibition zone, viz., 8.58, 8.55, 8.52, 8.49 and 8.41 (mm), respectively, at the highest tested concentration (75 ppm, parts per million) compared with the control. It is probable that the decoction's interaction with the pathogen population on the host plant will need to be considered in future experiments. However, at this moment, more research into the effective management of cotton bacterial blight by plant extracts in terms of concentration determination and development of biopesticides will provide future avenues to avoid environmental pollution.

3.
Pak J Pharm Sci ; 34(1(Supplementary)): 327-335, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34275858

RESUMO

Piroxicam (PC) is a non-steroidal anti-inflammatory drug characterized by poor aqueous solubility and reported to cause and impart crucial GIT irritation, bleeding, peptic and duodenal ulcer. Engineering of PC loaded microcapsules and its surface modification using different polymers has become the popular approach to address the said issues. The purpose of the study was to develop new PC loaded gastro-protective polymer hybrid microspheres (PHM) with subsequent conversion to tablet dosage form having modified dissolution rate and improved bioavailability. The crystallinity of the PC loaded PHM were established through powder X-ray diffraction. The optimised microspheres, PC-M1 with particle size 32±3.0µm, entrapment efficiency 83.78±2.5% and in vitro drug release 87.1±2.6% were further subjected to tablets development and in vivo evaluation. The in vitro drug release study conducted for PHM at pH media 1.2 and 6.8 demonstrated retarded and enhanced drug release rates (P<0.001) respectively. Both accelerated and real time stability studies confirmed stability of the PC loaded PHM based tablets. A substantial improvement in the drug plasma concentration 12.6±2.36 (P<0.001) was observed for the produced tablets compared to the marketed formulations.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Derivados da Hipromelose , Piroxicam/administração & dosagem , Piroxicam/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Preparações de Ação Retardada , Desenvolvimento de Medicamentos , Liberação Controlada de Fármacos , Técnicas In Vitro , Microesferas , Tamanho da Partícula , Difração de Pó , Coelhos , Comprimidos , Difração de Raios X
4.
PLoS One ; 16(7): e0253798, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34252095

RESUMO

Anthropogenic activities such as mining, manufacturing, and application of fertilizers release substantial quantities of cadmium (Cd) into the environment. In the natural environment, varying pH may play an important role in the absorption and accumulation of Cd in plants, which can cause toxicity and increase the risk to humans. We conducted a hydroponic experiment to examine the impact of pH on cadmium (Cd) solubility and bioavailability in winter wheat (Triticum aestivum L.) under controlled environmental conditions. The results showed that Cd concentration was significantly reduced in wheat with an increase in pH from 5 to 7, while it was dramatically increased at pH ranging from 7 to 9. However, in both cases, a significant reduction in physiological traits was observed. The addition of Cd (20, 50, and 200 µmol L-1) at all pH levels caused a substantial decline in wheat growth, chlorophyll and carotenoids contents, nutrient availability, while elevated cell membrane damage was observed in terms of electrolytic leakage (EL), osmoprotectants, and antioxidants activity. In our findings, the negative effects of acidic pH (5) on wheat growth and development were more pronounced in the presence of Cd toxicities. For instance, Cd concentration with 20, 50, and 200 µmol L-1 at acidic pH (5) reduced shoot dry biomass by 45%, 53%, and 79%, total chlorophyll contents by 26%, 41%, 56% while increased CAT activity in shoot by 109%, 175%, and 221%, SOD activity in shoot by 122%, 135%, and 167%, POD activity in shoot by 137%, 250%, and 265%, MDA contents in shoot by 51%, 83%, and 150%, H2O2 contents in shoot by 175%, 219%, and 292%, EL in shoot by 108%, 165%, and 230%, proline contents in shoot by 235%, 280%, and 393%, respectively as compared to neutral pH without Cd toxicities. On the other hand, neutral pH with Cd toxicities alleviated the negative effects of Cd toxicity on wheat plants by limiting Cd uptake, reduced reactive oxygen species (ROS) formation, and increased nutrient availability. In conclusion, neutral pH minimized the adverse effects of Cd stress by minimizing its uptake and accumulation in wheat plants.


Assuntos
Cádmio/toxicidade , Poluentes do Solo/toxicidade , Solo/química , Triticum/crescimento & desenvolvimento , Cádmio/metabolismo , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Hidroponia/métodos , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Poluentes do Solo/metabolismo , Triticum/química , Triticum/efeitos dos fármacos , Triticum/metabolismo
5.
J Infect Dis ; 216(suppl_1): S273-S279, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28838158

RESUMO

Background: The Basic Package of Health Services (BPHS) program has increased access to immunization services for children living in rural Afghanistan. However, multiple surveys have indicated persistent immunization coverage gaps. Hence, to identify gaps in implementation, an assessment of the BPHS program was undertaken, with specific focus on the routine immunization (RI) component. Methods: A cross-sectional survey was conducted in 2014 on a representative sample drawn from a sampling frame of 1858 BPHS health facilities. Basic descriptive analysis was performed, capturing general characteristics of survey respondents and assessing specific RI components, and χ2 tests were used to evaluate possible differences in service delivery by type of health facility. Results: Of 447 survey respondents, 27% were health subcenters (HSCs), 30% were basic health centers, 32% were comprehensive health centers, and 12% were district hospitals. Eighty-seven percent of all respondents offered RI services, though only 61% of HSCs did so. Compared with other facility types, HSCs were less likely to have adequate stock of vaccines, essential cold-chain equipment, or proper documentation of vaccination activities. Conclusions: There is an urgent need to address manpower and infrastructural deficits in RI service delivery through the BPHS program, especially at the HSC level.


Assuntos
Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Programas de Imunização/estatística & dados numéricos , Vacinação/estatística & dados numéricos , Afeganistão/epidemiologia , Estudos Transversais , Instalações de Saúde/estatística & dados numéricos , Serviços de Saúde/estatística & dados numéricos , Humanos , Vacinas/provisão & distribuição
6.
Asian J Transfus Sci ; 8(2): 113-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25161351

RESUMO

BACKGROUND: Maternal red blood cell (RBC) alloimmunization may lead to production of harmful antibodies that result in hemolytic disease of fetus and newborn (HDFN). There is insufficient data on the prevalence of HDFN due to RBC alloantibodies in the Malay neonatal population. AIM: The aim of this study was to determine the incidence of HDFN in the Malay neonatal population due to clinically significant RBC alloantibodies. SUBJECTS AND METHODS: A cross sectional study was conducted in Transfusion Medicine Unit, Hospital Universitiy Sains Malaysia over one year period from January to December 2009. A total of 5163 Malay pregnant women who attended labor room for delivery were collected and analyzed prospectively. The blood samples were subjected to the standard immunohematological procedure for RBC antibody screening and identification using reagents of Diamed-ID Gel microtyping system. All the newborns with RBC alloantibody were investigated for the evidence of HDFN. RESULTS: Thirty (0.58%) women were found to have clinically significant RBC alloantibodies. Most of the alloantibodies belonged to Rhesus (Rh) system (56.7%) where anti-E (33.3%) was the most common followed by anti-D (10.0%). Rh antibodies were the main cause of HDFN in fourteen (0.27%) neonates. Anti-D and anti-c were identified to cause moderate to very severe HDFN. CONCLUSIONS: With the low prevalence of clinically significant RBC alloantibodies and HDFN, routine antenatal antibody screening practice may not be advised as a routine practice at present, preferably reserved for those women of RhD negative or with history of HDFN, significantly of those attributed to anti-c.

7.
Malays J Med Sci ; 10(2): 93-5, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23386805

RESUMO

A 66-year-old Malay woman, known hypertensive, presented with post menopausal bleeding associated with clot for three months. She was postmenopausal for last ten years. She also complaints of developing a mass in the abdomen which was growing in size also for last three months. Abdominal examination revealed a twenty week size mass, movable from side to side but unable to get below the mass. Vaginal examination revealed a fleshy fungating mass arising from the uterus coming out through the vagina. Cervix could not be visualized properly. Subsequent histopathology of the removed mass was reported as a Malignant Mixed Mullerian Tumour - Heterologous.

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