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1.
Chinese Pharmaceutical Journal ; (24): 86-90, 2019.
Artigo em Chinês | WPRIM | ID: wpr-858091

RESUMO

OBJECTIVE: To search more effective antibacterial candidate agents by designing a series of 7-phosphoryl quinolone derivatives,exploring the synthetic methods, and evaluating their antibacterial activities. METHODS: The quinolone derivatives were synthesized using phosphate and quinolone intermediates as raw materials and alkaline ionic liquid [Bmim] OH as catalyst with microwave assistance. The antibacterial activities of the products were evaluated by agar dilution method. RESULTS: Eight title compounds were prepared, and their structures were clearly established by IR, NMR and MS. The in vitro experiment showed that the derivatives had potential antibacterial activity. Especially, compound Ⅱc showed more potent activities against S. aureus, E. coli, MREC-1# and MREC-2# with minimum inhibitory concentrations (MICs) of 1.6, 6.4, 12.8,6.4 mg•mL-1, respectively, and the MICs of compound Ⅱ gagainst S. aureus, E. coli, MREC-1# and MREC-2# were 1.6, 3.2, 6.4, 6.4 mg•mL-1, respectively. Its activity on drug-resistant bacteria was better than that of the control drug norfloxacin. CONCLUSION: The quinolone derivatives are highly active on drug-resistant bacteria.It is worth of further study.

2.
Acta Pharmaceutica Sinica ; (12): 420-2016.
Artigo em Chinês | WPRIM | ID: wpr-779186

RESUMO

In search of more effective anticancer agents, twelve compounds were designed and synthesized via microwave-assisted reactions of cinnamoyl chloride with α-hydroxyphosphonate. The structures of all the compounds were confirmed by IR, NMR and elemental analysis. Bioassay of the compounds were tested. They exhibited certain antitumor activities. Especially, compound 3c had obvious inhibitory effect on growth of SGC-7901 cells in vitro at 20 μmol·L-1, and compound 3h showed better inhibitory effect on growth of SGC-7901 cells in vitro at 5 μmol·L-1, the inhibition ratio were 68.8% and 48.0%, respectively.

3.
Artigo em Inglês | IMSEAR | ID: sea-166883

RESUMO

The research work was involved in rapid and efficient procedure for the attachment of barbituric acid with arylidene acetophenone under microwave irradiation (MWI) and conventional heating. The result showed that the time was reduced from the conventional 24 hours to 5-10 minutes. In conventional heating, the yield of the compounds 2a-2e were very poor (75-81%), but in MW methods the yields were observed 96.48-98% which was comparatively too high. The structures of the compounds were characterized by FT-IR, 1H-NMR spectral data. The antimicrobial and cytotoxic activities of the synthesized compounds were also investigated. Staphylococcus aureus, Bacillus megaterium, Escherichia coli and Pseudomonas aeruginosa revealed the zone of inhibition were 6-12 mm where sample concentration was 100 μg/disc. However, cytotoxic analysis, the mortality 47-95% were appeared when sample concentration were 0.78-25 (μg/ml) and more than 50 (μg/ml) concentration showed 100% mortality. The presence of a reactive and unsaturated ketone function in synthesized compounds was found to be responsible for their potential antimicrobial and cytotoxic activity.

4.
Artigo em Inglês | IMSEAR | ID: sea-177120

RESUMO

Owing to widespread applications, synthesis and characterization of silver nanoparticles is recently attracting considerable attention. Increasing environmental concerns over chemical synthesis routes have resulted in attempts to develop biomimetic approaches. One of them is synthesis using plant parts, which eliminates the elaborate process of maintaining the microbial culture and often found to be kinetically favorable than other bioprocesses. The present study deals with investigating the effect of process microwave irradiation, interaction time on the morphology and size of silver nanoparticles synthesized using aqueous extract of Tulsi. Plant extract from ocimum sanctum (Tulsi) was used for the synthesis of silver nanoparticles (AgNPs) from silver nitrate solution. Silver nanoparticles were characterized by UV-Vis spectrophotometer and scanning electron microscope (SEM). The formation and stability of the reduced silver nanoparticles in the colloidal solution was monitored by UV-Vis spectrophotometer analysis. Nanoparticles ranges from 20 to 40 nm in size with nearly spherical shape were produced. SEM determination of the brown color stable samples showed the formation of silver nanoparticles and well dispersed nanoparticles could be seen in the samples treated with silver nitrate. These silver nanoparticles have proven to be stable for more than 3 months. It can be inferred from the study that fne tuning the bioprocess parameters will enhance possibilities of desired nano-product tail or made for particular applications.

5.
Artigo em Inglês | IMSEAR | ID: sea-153013

RESUMO

N-aryl/heteryl acetoacetamides are the intermediates used in the synthesis of various heterocyclic compounds like 1,4-dihydropyridines, pyrimidines etc. Three different substituted N-aryl/heteryl acetoacetamide derivatives (I-III) have been prepared from the reaction of ethylacetoacetate and three different aryl/heteryl primary amines under solvent free conditions using potassium tert-butoxide as catalyst. The reactions were carried out by two different methods (viz., Conventional and Microwave irradiation) and they are simple, eco-friendly and economical. All reactions were processed for optimization with different ratios of aryl/heteryl amine and ethylacetoacetate like1:1,1:1.2,1:1.4,1:1.6,1:1.8,1:2 and a comparison was made between the percentage yields with each ratio. Highest percentage yield was observed with 1:1.8 ratio for I & II and 1:1.6 ratio for III in both the methods. However, the microwave irradiation method was found to be superior to the conventional method. The newly synthesized compounds have been purified by recrystallization and characterized by physical and spectral data.

6.
Braz. dent. j ; 24(5): 487-491, Sep-Oct/2013. tab
Artigo em Inglês | LILACS | ID: lil-697640

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) can grow as structured biofilm in different surfaces, including oral mucosa and denture surfaces. Such biofilms can be released into the oral fluids and aspirated, causing systemic infections such as aspiration pneumonia. This study evaluated the efficacy of two disinfectant solutions and microwave irradiation in disinfecting acrylic specimens contaminated with MRSA biofilm. Thirty-six acrylic specimens were made, sterilized and contaminated with MRSA (107 cfu/mL). After incubation (37 °C/48 h), the specimens were divided into 4 groups: not disinfected (positive control); soaking in 1% sodium hypochlorite for 10 min; soaking in 2% chlorhexidine gluconate for 10 min; and irradiating by microwave for 3 min at 650 W. The viability of cells was evaluated by XTT reduction method. All specimens from the positive control group showed biofilm formation after 48 h incubation. The mean absorbance value of the control specimens was 1.58 (OD at 492 nm). No evidence of biofilm formation was observed on specimens after the disinfection methods. Disinfection by soaking in 1% sodium hypochlorite and 2% chlorhexidine gluconate and irradiating by microwaves resulted in 100% reduction of MRSA biofilm metabolism. The use of chemical solutions and microwave irradiation was shown to be effective for eradicating mature MRSA biofilms on acrylic resin specimens.


Staphylococcus aureus resistente à meticilina (MRSA, do inglês methicillin-resistant Staphylococcus aureus) pode crescer como biofilme estruturado em diferentes superfícies, incluindo mucosa bucal e superfícies de próteses. Estes biofilmes podem se dispersar nos fluidos orais e ser aspirados, causando infecções sistêmicas, como a pneumonia aspirativa. Este estudo avaliou a eficácia de duas soluções desinfetantes e irradiação por microondas na desinfecção de corpos-de-prova acrílicos contaminados com biofilme de MRSA. Trinta e seis espécimes de resina acrílica foram fabricados, esterilizados e contaminados com MRSA (107 ufc/mL). Após a incubação (37 °C/48 h), os espécimes foram divididos em quatro grupos: não desinfetados (controle positivo); imersos em hipoclorito de sódio 1% por 10 min; imersos em gluconato de clorexidina 2% por 10 min e irradiados por microondas durante 3 min a 650 W. A viabilidade das células foi avaliada pelo método de redução de XTT. Todos os espécimes do grupo controle apresentaram formação de biofilme após 48 h de incubação. O valor médio de absorbância destes espécimes foi de 1.58 (OD a 492 nm). Nenhuma evidência de formação de biofilme foi observada em todas as amostras desinfetadas. A desinfecção em hipoclorito de sódio 1%, gluconato de clorexidina 2% e irradiação em microondas resultou em 100% de redução do metabolismo do biofilme de MRSA. O uso de soluções químicas e irradiação em microondas mostrou-se eficaz na eliminação do biofilme maduro de MRSA sobre corpos-de-prova de resina acrílica.


Assuntos
Acrilatos , Biofilmes , Desinfetantes/farmacologia , Micro-Ondas , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Clorexidina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos da radiação , Propriedades de Superfície , Hipoclorito de Sódio/farmacologia
7.
Artigo em Inglês | IMSEAR | ID: sea-151705

RESUMO

A series of 5-benzylidene-3-α-carboxy ethylrhodanine derivatives (3a-m) were synthesized using 3-α-carboxy ethylrhodanine with various substituted aromatic aldehydes in anhydrous sodium acetate in glacial acetic acid by the knoevenagal condensation under microwave irradiation. The compounds synthesized within short time 10-15 min and in good yields. All the compounds characterized by IR, UV, 1H & 13C-NMR and MS spectral data and studied in vitro antibacterial activity.

8.
Artigo em Inglês | IMSEAR | ID: sea-167956

RESUMO

N-aryl/heteryl acetoacetamides are the intermediates used in the synthesis of various heterocyclic compounds like 1,4-dihydropyridines, pyrimidines etc. Three different substituted N-aryl/heteryl acetoacetamide derivatives (I-III) have been prepared from the reaction of ethylacetoacetate and three different aryl/heteryl primary amines under solvent free conditions using potassium tert-butoxide as catalyst. The reactions were carried out by two different methods (viz., Conventional and Microwave irradiation) and they are simple, eco-friendly and economical. All reactions were processed for optimization with different ratios of aryl/heteryl amine and ethylacetoacetate like1:1,1:1.2,1:1.4,1:1.6,1:1.8,1:2 and a comparison was made between the percentage yields with each ratio. Highest percentage yield was observed with 1:1.8 ratio for I & II and 1:1.6 ratio for III in both the methods. However, the microwave irradiation method was found to be superior to the conventional method. The newly synthesized compounds have been purified by recrystallization and characterized by physical and spectral data.

9.
Artigo em Inglês | IMSEAR | ID: sea-163695

RESUMO

2-Aryl/heteryl-3-aryloxy/heteryloxy-4H-chromones 5 have been synthesized through a series of reactions starting from phenols under microwave irradiation. This process is an effective alternative to the traditional thermal heating method. The yields are excellent and the reaction time is in a few minutes. These compounds have been characterized on the basis of IR, 1H NMR, 13C NMR and Mass spectrometry and evaluated for antibacterial activity.

10.
Artigo em Inglês | IMSEAR | ID: sea-162282

RESUMO

Microwave assisted new aldol condensation reaction of 1-oxo-1,2,3,4- tetrahydrocarbazoles 1 with thiophene-2-carbaldehyde 2 in the presence of alcoholic KOH affords a single product 2-Thiophen-2-ylmethylene-2,3,4,9-tetrahydro-carbazol-1-one 3. 3 on irradiation with hydroxylamine hydrochloride yielded 3-Thiophen-2-yl-4,5-dihydro-10H-2-oxa-1,10-diazacyclopenta[ a]carbazole 4 and 3 on irradiation with hydrazine hydrate in ethanol medium to yielded 3-Thiophen-2-yl-2,4,5,10-tetrahydro-1,2,10-triaza-cyclopenta[a]carbazole 5. The structures of the synthesized compounds were confirmed on the basis of physical and spectral analysis (FT-IR, 1H, 13C-NMR) and Mass spectral data.

11.
Chinese Journal of Experimental Ophthalmology ; (12): 17-20, 2011.
Artigo em Chinês | WPRIM | ID: wpr-635330

RESUMO

Background Conventional chemical method to fix the entire eyeball results in the edema of retinal nerve fiber layer and therefore influent the evaluation of tissue structure.Research showed that microwave irradiation can avoid this phenomenon. Objective This study was to investigate the appropriate energy and time duration of microwave irradiation for fixation of rabbit eyes specimen and compare the influence of different fixation methods on retinal structure. Methods Twenty-two New Zealand white rabbits were sacrificed by using venous air embolism.The eyeballs were enucleated from the rabbits and immersed in chemical reagents with glacial acetic acid,methyl aldehyde and chloroform for 2 days as the control group.The eyeballs were immersed in 400 ml physiological balance solution immediately,and then were fixed by microwave irradiation for 80,160,240 and 320 seconds under the lower power as the microwave irradiation groups.In the microwave irradiation+chemical fixation group,the specimens were immersed in chemical reagents for 1-2 hours after the microwave radiation.The morphology of retinal structure was examined and area of retinal detachment was calculated by hemotoxylin and eosin staining under the light microscope. Results A better fixation effect was obtained in the retinal section of microwave radiation for 240 seconds in comparison with that of the traditional chemical reagent fixation method for 2 days.The retina detachment ratio was 16.3%±11.5% for simple microwave method,50.0%±24.5% for chemical method,and 6.7%±7.8% for microwave+chemical method.showing a significant difference among 3 groups(F=32.43,P=0.000).Retinal staining was clear and retinal structure was almost normal in the specimens of microwave+chemical fixation group with 200-240 seeonds microwave irradiation and 1-2 hours chemical fixation. Conclusion Microwave irradiation method is a more ideal way for the fixation of retina because of taking short duration,lower toxicity and better staining.The combination of microwave radiation and chemical reagents can acquire an excellent quality of retinal section.

12.
Chinese Journal of Practical Nursing ; (36): 5-8, 2011.
Artigo em Chinês | WPRIM | ID: wpr-414663

RESUMO

Objective The purpose of this study was to evaluate the disinfection effectiveness and properties of acrylic resin via microwave irradiation. Methods Forty acrylic resin base dentures fabricated in a standardized procedure were chosen and divided into Group A,B,C and D randomly. Group A,B and C were immersed in 200ml distilled water and submitted to microwave irradiation at 700W for 3,4,5 minutes individually. Group D was used as positive control. Bacteria specimens from each group were got for culture and numbers were calculated. Then the four groups were tested for the flexural strength and impact strength by universal test machine before and after microwave irradiation sterilization. Results The germicidal ratio of Group B was more than 90% ,while the ratio of group C was 100%. There was no significant difference in flexural strength and impact strength between group C and group D. Conclusions Microwave irradiation for 5 minutes at 700W produced sterilization of dentures contaminated with all bacteria whereas the denture strength is not affected. Microwave irradiation at 700W solution for 5 minutes was effective to sterilize acrylic resin base dentures.

13.
Chinese Journal of Radiation Oncology ; (6): 377-380, 2008.
Artigo em Chinês | WPRIM | ID: wpr-398801

RESUMO

Objective To clarify the temperature curve of the irradiation target area,its adjacent tissue and the whole body during extracorpereal microwave irradiation, then to compare and optimize different irradiation models. Methods Different parts of the chest of adult New Zealand white rabbit were irradiated using different extracorporeal microwave irradiation models. The temperature of the irradiated skin, the subcutaneous and deep parts, the adjacent tissues and the anus was measured. The experiment was bi-factor and multi-level designed according to the repeatedly measured data and the rabbits was divided into group a,b,c and d. Results The increase rate of the surface temperature in the dorsal lung was similar between group d and group b1(F=10.04,P<0.01). However,the increase rate of the surface temperature in the ventral lung of group d was lower, and the mean temperature of this site measured 10 minutes later was also lower than group b1(F=10.04,P<0.01). The increase rate of the rectal temperature of group d was higher,and the mean rectal temperature tested 10 minutes later was also higher than group b1(F=7.04,P<0.01). Conclusions Multi-array irradiation could achieve satisfactory irradiation depth and appropriate therapeutic temperature. Well controlled extracorporeal microwave irradiation under is an ideal thermotherapy method.

14.
Chinese Journal of Bases and Clinics in General Surgery ; (12)2003.
Artigo em Chinês | WPRIM | ID: wpr-542158

RESUMO

Objective To investigate the irradiating effect of low intensive microwave(LIM) on pathological process of blood vessel restenosis(RS) and assess the probability of LIM irradiation to prevent was used RS.(Methods Forty-four) male healthy New Zealand rabbits were randomly divided into 2 groups.Fogarty catheter traumatize to the tunica intima of iliac artery so as to establish RS models.Two thousand four hundred and fifty MHz microwave with different power of 2,5 and 10 mW/cm~2 was used,locally to irradiate EIA in irradiating group(1 h/d).Specimens were obtained at different time of 3,7,14 and 28 d after operation.Morphological changes of tissues were observed with HE and EF staining and the area of tunica intima,tunica media and the rate of cavity stenosis were analyzed with image analysis system;apoptosis was detected with TUNEL;phenotype and microstructure of VSMC were observed with TEM.Results After microwave irradiating,inflammatory reaction in early period was suppressed,mural thrombus decreased,the proliferation and migration of VSMC depressed,the area of tunica intima and the rate of cavity stenosis obviously reduced comparing with the control group(P0.05).At other different time,however,the rate of apoptosis cells in irradiating groups obviously increased than that of the control group(P

15.
Chinese Journal of Marine Drugs ; (6)2000.
Artigo em Chinês | WPRIM | ID: wpr-585449

RESUMO

Objective To study the effect of microwave irradiation on a marine mutant strain B1 which had high antifungal activity,and obtain the optimum dosage of microwave irradiation.Methods The marine strain B1(Bacillus sp.) was radiated by 2450 MHz microwave for various times.The mutation rate p,mutation mean ? and the mutation variance ?~(2) were estimated by statistical methods.From these mutants,a high-activity strain B1-413 was obtained,and its genetic attribute was tested.Results Microwave irradiation was highly effective at 60 s.The MIC of mutant strain B1-413 was reduced from 125?l?mL~(-1)to 32?l? mL~(-1) compared with B1,the genetic attribute of which was stable through four generation cultivation.Conclusion The B1 was sensitive to microwave irradiation,and the higher anti-fungi active mutants can be easy obtained after the treatment of microwave irradiation.

16.
Traditional Chinese Drug Research & Clinical Pharmacology ; (6)1993.
Artigo em Chinês | WPRIM | ID: wpr-573247

RESUMO

Objective To observe the preventive and therapeutic effect of Chinese herbal medicine film µwave irradiation on mammary hyperplasia in rats. Methods Rat models of experimental mammary hyperplasia were established by intramuscular injection of estrogen and a small quantity of progestin. Two weeks after modeling, the rats were treated with Chinese herbal medicine film µwave irradiation. Before and after the treatment, mammary diameter of the second nipples were measured, serum concentrations of estrogen (E2), progesterone (P) and prolactin (PRL) were determined by radioimmunoassay,pathological changes of mammary hyperplasia were examined under microscope,and the rate of mammary hyperplasia was measured. Results Chinese herbal medicine film markedly inhibited experimental mammary hyperplasia in rats,and the rate of mammary hyperplasia were 23.4 %in medicine film group and 20.9 %in medicine film µwave irradiation group respectively. Medicine film regulated the concentrations of estrogen and progestin,reduced the level of PRL and alleviated the pathological severity of mammary hyperplasia obviously. Conclusion Chinese herbal medicine film µwave irradiation have certain preventive and therapeutic effect on mammary hyperplasia in rats.

17.
Academic Journal of Second Military Medical University ; (12)1985.
Artigo em Chinês | WPRIM | ID: wpr-549731

RESUMO

Fourteen dogs were examined for their serum hydrocortisone levels after receiving microwave irradiation in liver,Serum hydrocortisone rose to its peak at the second hour after irradiation, began to fall at the 15th hour and finally returned to the original level at the 24 hour

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