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1.
Sci Rep ; 14(1): 9663, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38670984

RESUMO

It is mentioned that understanding linear and non-linear thermo-elasticity systems is important for understanding temperature, elasticity, stresses, and thermal conductivity. One of the most crucial aspects of the current research is the solution to these systems. The fractional form of several thermo-elastic systems is explored, and elegant solutions are provided. The solutions of fractional and integer thermo-elastic systems are further discussed using tables and diagrams. The closed contact between the LRPSM and exact solutions is displayed in the graphs. Plotting fractional problem solutions demonstrates their convergence towards integer-order problem solutions for suitable modeling. The tables confirm that greater precision is rapidly attained as the terms of the derived series solution increase. The faster convergence and stability of the suggested method support its modification for other fractional non-linear complex systems in nature.

2.
Bioorg Chem ; 91: 103112, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31349115

RESUMO

Alpha-amylase and urease enzyme over expression endorses various complications like rheumatoid arthritis, urinary tract infection, colon cancer, metabolic disorder, cardiovascular risk, and chronic kidney disease. To overcome these complications, we have synthesized new arylhydrazide bearing Schiff bases/thiazolidinone analogues as α-amylase and urease inhibitors. The analogues 1a-r were evaluated for α-amylase inhibitory potential. All analogues were found active and show IC50 value ranging between 0.8 ±â€¯0.05 and 12.50 ±â€¯0.5 µM as compare to standard acarbose (IC50 = 1.70 ±â€¯0.10 µM). Among the synthesized analogs, compound 1j, 1r, 1k, 1e, 1b and 1f having IC50 values 0.8 ±â€¯0.05, 0.9 ±â€¯0.05, 1.00 ±â€¯0.05, 1.10 ±â€¯0.10, 1.20 ±â€¯0.10 and 1.30 ±â€¯0.10 µM respectively showed an excellent inhibitory potential. Analogs 2a-o were evaluated against urease activity. All analogues were found active and show IC50 value ranging between 4.10 ±â€¯0.02 and 38.20 ±â€¯1.10 µM as compare to standard thiourea (IC50 = 21.40 ±â€¯0.21 µM). Among the synthesized analogs, compound 2k, 2a, 2h, 2j, 2f, 2e, 2g, 2b and 2l having IC50 values 4.10 ±â€¯0.02, 4.60 ±â€¯0.02, 4.70 ±â€¯0.03, 5.40 ±â€¯0.02, 6.70 ±â€¯0.05, 8.30 ±â€¯0.3, 11.20 ±â€¯0.04, 16.90 ±â€¯0.8 and 19.80 ±â€¯0.60 µM respectively showed an excellent inhibitory potential. All compounds were characterized through 1H, 13C NMR and HR-EIMS analysis. Structure activity relationship of the synthesized analogs were recognized and confirmed through molecular docking studies.


Assuntos
Inibidores Enzimáticos/farmacologia , Hidrazinas/farmacologia , Simulação de Acoplamento Molecular , Tiazolidinas/farmacologia , Urease/antagonistas & inibidores , alfa-Amilases/antagonistas & inibidores , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Hidrazinas/síntese química , Hidrazinas/química , Estrutura Molecular , Bases de Schiff/química , Bases de Schiff/farmacologia , Relação Estrutura-Atividade , Tiazolidinas/química , Urease/metabolismo , alfa-Amilases/metabolismo
3.
J Photochem Photobiol B ; 190: 59-65, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30500677

RESUMO

Ajuga bracteosa (A. bracteosa) is one of the critically endangered and high-valued medicinal plants worldwide. Light is one of the major factor or stimulus involved in the morphogenic responses and bioactive compounds production in various medicinal plants. In this study, unique properties of colored lights have been observed on induction of somatic embryos from non-embryonic calli cultures of A. bracteosa. The maximum callogenic response (92.32%) from leaf explants was observed on Murashige and Skoog (MS) medium augmented with benzyl adenine (BA; 2.0 l-1) and 2, 4-Dichlorophenoxy acetic acid (2.4-D; 1.0 mg l-1). Calli cultures with same hormonal concentrations were placed under different spectral lights for somatic embryogenesis and photochemical variations. Red lights were found effective for maximum somatic embryos induction (92.75%) with optimum biomass accumulation (152.64 g l-1) on day 40. Similarly, among all the spectral lights, red light exhibited the highest DPPH-radical scavenging activity (DRSA; 92.86%). In contrast, blue lights induced maximum biosynthesis of chemically important total phenolics content and total flavonoids content (TPC; 0.264 and TFC; 0.06 mg/g-DW), respectively. Furthermore, blue, green and red lights also enhanced phenolics and production, polyphenolics content and total polyphenolics production in somatic embryos. It is concluded that exposure of calli cultures to colored lights provides an effective and promising in vitro technique for conservation of endangered A. bracteosa species and enhancement of its bioactive compounds. Steps should be taken to adopt these strategies/ techniques at a larger scale in order to yield maximum benefits from this highly valued medicinal plant species.


Assuntos
Ajuga/fisiologia , Desenvolvimento Embrionário/efeitos da radiação , Plantas Medicinais/fisiologia , Biomassa , Cor , Flavonoides/análise , Luz , Fenóis/análise
4.
J Photochem Photobiol B ; 154: 51-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26688290

RESUMO

Stevia rebaudiana (S. rebaudiana) is a very important species with worldwide medicinal and commercial uses. Light is one of the major elicitors that fluctuate morphogenic potential and biochemical responses. In the present study, we investigated the effect of various spectral lights on biomass accumulation and secondary metabolite production in callus cultures of S. rebaudiana. Leaf explants were placed on Murashige and Skoog (MS) medium and exposed to various spectral lights. 6-Benzyle adenine (BA) and 2, 4-dichlorophenoxy acetic acid (2, 4-D; 2.0 mgl(-1)) were used for callus induction. The control light (16/8h) produced optimum callogenic response (92.73%) than other colored lights. Compared to other colored lights, control grown cultures displayed maximum biomass accumulation (5.78 gl(-1)) during a prolonged log phase at the 18th day of growth kinetics. Cultures grown under blue light enhanced total phenolic content (TPC; 102.32 µg/g DW), total flavonoid content (TFC; 22.07 µg/g DW) and total antioxidant capacity (TAC; 11.63 µg/g DW). On the contrary, green and red lights improved reducing power assay (RPA; 0.71Fe(II)g(-1) DW) and DPPH-radical scavenging activity (DRSA; 80%). Herein, we concluded that the utilization of colored lights is a promising strategy for enhanced production of antioxidant secondary metabolites in callus cultures of S. rebaudiana.


Assuntos
Antioxidantes/metabolismo , Luz , Folhas de Planta/efeitos da radiação , Stevia/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacologia , Antioxidantes/química , Compostos de Benzil , Biomassa , Flavonoides/química , Flavonoides/metabolismo , Herbicidas/farmacologia , Cinetina/farmacologia , Fenóis/química , Fenóis/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Purinas , Stevia/química , Stevia/crescimento & desenvolvimento
5.
Trop Med Int Health ; 9(3): 335-42, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14996362

RESUMO

Synthetic repellents based on di-ethyl 3-methyl benzamide (DEET) are a popular method of obtaining protection from mosquitoes and yet clear evidence for a protective effect against malaria has hitherto never been convincingly demonstrated. A household randomized trial was undertaken among a study population of 127 families (25%) in an Afghan refugee village in Pakistan to compare the efficacy of repellent soap (Mosbar containing 20% DEET and 0.5% permethrin) vs. a placebo lotion. Cases of falciparum and vivax malaria were detected by passive case detection at the camp's clinic. At the end of the 6 month trial 3.7% (23 of 618) of individuals in the Mosbar group had presented with one or more episodes of falciparum malaria compared with 8.9% (47 of 530) of the placebo group (odds ratio 0.44, 95% CI 0.25-0.76). 16.7% of the Mosbar group (103 of 618) presented with vivax malaria compared with 11.7% (62 of 530) of the placebo group, and thus no effect was shown against vivax malaria (odds ratio 1.29, 95% CI 0.86-1.94). A considerable proportion of individuals (22%) had presented with vivax malaria during the 7 months leading up to the trial and thus any intervention effect would be partially masked by relapsed infections. The distribution of mosquitoes among households was broadly similar between Mosbar and placebo groups. The repellent was popularly received and very few side-effects were reported. There is a case for giving repellents more prominence in public health as a preventive measure in regions where vectors bite in the early evening or in emergency situations such as epidemics or newly established refugee camps.


Assuntos
DEET/administração & dosagem , Surtos de Doenças/prevenção & controle , Repelentes de Insetos/administração & dosagem , Malária Falciparum/prevenção & controle , Malária Vivax/prevenção & controle , Refugiados , Adolescente , Adulto , Afeganistão/etnologia , Distribuição por Idade , Animais , Criança , Pré-Escolar , Feminino , Humanos , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Masculino , Paquistão/epidemiologia , Recidiva
6.
Physiol Plant ; 120(4): 556-562, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15032817

RESUMO

Exposure to a chilling temperature of 2.5 degrees C for 96 h inhibited the subsequent growth of cucumber seedling radicles at 25 degrees C by 92%. Exposing seedling with 5 +/- 1 mm long radicles to acetaldehyde vapour (275 micro l l(-1)) or to an aqueous ethanol solution (0.6 M) for 2 h, or to 45 degrees C for 10 min before chilling, increased chilling tolerance so that the chilling treatment reduced growth by only 47, 39 or 36%, respectively. All of these effective treatments induced the synthesis of a number of proteins, and suppressed de novo protein synthesis (i.e. the incorporation of [(35)S]-methionine) by about 70%. In contrast, treatment for 2 h with an aqueous arsenite solution (100 micro M) had no effect on chilling sensitivity or the incorporation of [(35)S]-methionine, yet it induced the synthesis of a complement of proteins that were similar to that induced by the effective heat-shock treatment. A unique protein or set of proteins may be responsible for heat-shock-induced chilling tolerance, but none was detected. The ability of various abiotic stresses to suppress protein synthesis may be more important in increasing tolerance to chilling injury than their ability to induce the synthesis of specific proteins.

7.
Trop Med Int Health ; 7(10): 813-22, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12358615

RESUMO

Malaria is often a major health problem in countries undergoing war or conflict owing to breakdown of health systems, displacement of vulnerable populations, and the increased risk of epidemics. After 23 years of conflict, malaria has become prevalent in many rural areas of Afghanistan. From 1993 to the present, a network of non-governmental organizations, co-ordinated by HealthNet International, has operated a programme of bednet sales and re-treatment in lowland areas. To examine whether a strategy based on insecticide-treated nets (ITN) is a viable public health solution to malaria, communities were given the opportunity to buy nets and then monitored to determine population coverage and disease control impact. This was carried out using two contrasting methods: cross-sectional surveys and passive surveillance from clinics using a case-control design. Nets were purchased by 59% of families. Cross-sectional surveys demonstrated a 59% reduction in the risk of Plasmodium falciparum infection among ITN users compared with non-users (OR 0.41; 95% CI 0.25-0.66). The passive surveillance method showed a comparable reduction in the risk of symptomatic P. falciparum malaria among ITN users (OR 0.31; 95% CI 0.21-0.47). The cross-sectional method showed a 50% reduction in risk of P. vivax infection in ITN users compared with non-users (OR 0.50; 95% CI 0.17-1.49) but this effect was not statistically significant. The passive surveillance method showed a 25% reduction in the risk of symptomatic P. vivax malaria (OR 0.75; 95% CI 0.66-0.85). ITN appeared to be less effective against P. vivax because of relapsing infections; hence an effect took more than one season to become apparent. Passive surveillance was cheaper to perform and gave results consistent with cross-sectional surveys. Untreated nets provided some protection. Data on socioeconomic status, a potential confounding factor, was not collected. However, at the time of net sales, there was no difference in malaria prevalence between buyers and non-buyers. The abundance of Anopheles stephensi, the main vector, did not appear to be affected by ITN. ITN constitute one of the few feasible options for protection against malaria in chronic emergencies.


Assuntos
Roupas de Cama, Mesa e Banho , Inseticidas/administração & dosagem , Malária Falciparum/prevenção & controle , Malária Vivax/prevenção & controle , Marketing de Serviços de Saúde , Plantas , Adolescente , Afeganistão/epidemiologia , Animais , Anopheles/crescimento & desenvolvimento , Roupas de Cama, Mesa e Banho/economia , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Masculino , Controle de Mosquitos/métodos , Vigilância da População , População Rural
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