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1.
A pyrimidne nucleobase, 5-phenylthio-2,4-bisbenzyloxypyrimidine and its analogs were synthesized and scanned for in vitro antifungal activity using cup-plate and macrobroth dilution method against Candida albicans, Aspergillus niger, Aspergillus flavus and Aspergllus fumigatus. In the cup-plate method, 5-phenylthio-2,4-bisbenzyloxypyrimidine showed very good antifungal activity compared to clotrimazole at the concentrations of 100 and 1000 μg/ml and in the macrobroth dilution method, it showed comparable activity with respect to standard drugs fluconazole and itraconaole. In vivo antifungal activity of 5-phenylthio-2,4-bisbenzyloxypyrimidine at the dose levels of 10 and 30 mg/kg was carried by causing systemic infection of mice using the same fungi used in in vitro testing. The results from in vivo studies with 5-phenylthio-2,4-bisbenzyloxypyrimidine and fluconazole indicated that 5-phenylthio-2,4-bisbenzyloxypyrimidine had similar potency as fluconazole at both dose levels.  相似文献   

2.
This study describes the synthesis, lipophilicity and in vitro antimicrobial assays of 15 new hydrazide–hydrazones of isonicotinic acid. New derivatives were obtained on the basis of the condensation reaction of isonicotinic acid hydrazide with different aromatic aldehydes. The chemical structure of synthesized compounds was confirmed by spectral methods. Experimental lipophilicity of new isonicotinic acid derivatives was determined using reversed‐phase thin‐layer chromatography. All synthesized compounds were subjected to in vitro antimicrobial assays against reference strains of Gram‐positive bacteria, Gram‐negative bacteria and fungi belonging to Candida spp. Some of the synthesized hydrazide–hydrazones proved to be significant antibacterial compounds and more potent than commonly used chemotherapeutic agents.  相似文献   

3.
目的 :观察替硝唑洗液的抗厌氧菌活性及对人阴道滴虫的杀灭作用。方法 :采用肉汤试管稀释法测定抗厌氧菌的MIC及MBC ;采用家兔阴道感染人阴道滴虫的模型 ,观察其抗阴道毛滴虫的作用。结果 :替硝唑洗液对 2 0 0株厌氧菌 (除乳杆菌、直杆菌外 )均有较好的抗菌活性 ,其MIC50 均在 2mg/L以下 ,MIC90 略高 ( 1 6mg/L) ,MBC约为MIC的 4~ 1 6倍。替硝唑洗液阴道内直接给药和阴道内冲洗 ,5mg/kg以上对阴道毛滴虫具有明显的杀灭作用 ,2 0mg/kg达痊愈。结论 :替硝唑洗液具有明显的抗厌氧菌活性 ,且对人阴道毛滴虫具有很好的杀灭作用 ,其杀灭滴虫的作用强度优于碧洁洗液  相似文献   

4.
This study investigated the antibacterial activity of human pleural fluid (HPF) and its interaction with gentamicin (GM), meropenem (MRPM), ciprofloxacin (CPFX) and clarithromycin (CLTM) against Escherichia coli K-12, Proteus rettgeri (Sanelli) and Staphylococcus aureus. Minimal inhibitory concentrations or volumes, expressed as MIC or volume percentage (MIV, V/V%), were measured using a micro-dilution technique in microtiter plates. The antimicrobial activity of HPF combinations with antimicrobial drugs was evaluated by the chequerboard method calculating the fractional inhibitory concentration index (FIC) values. HPF MIVs (%) were: 37.54; 19.85; 1.74 for E. coli, P. rettgeri and S. aureus, respectively. FIC values indicated a synergistic effect with GM, MRPM and CPFX against E. coli and P. rettgeri and an additive effect for the combination HPF plus CLTM or indifference with HPF plus GM and CPFX against S. aureus. The presence of antibodies, complement factors, lysozyme, -defensins and enzymes could explain the antimicrobial activity of HPF and its synergistic effect with certain antibiotics.  相似文献   

5.
The antifungal activity of 6-amino-2-n-pentylthiobenzothiazole (APB) against 26 strains of the genus Candida in vitro was studied. Susceptibility of 17 strains was IC50 ≤ 40 μmol/ml, of 7 strains IC50 = 40−80 μmol/ml and of 2 strains IC50 = 80−200 μmol/ml. Generalized candidosis of mice was treated with APB (doses 50, 100, 250 mg/kg) and ketoconazole (KET, 50 mg/kg of body weight). The optimal dose of APB was shown to be 100 mg/kg; 25% of mice survived after 14 days as compared to control animals. C. albicans was not found in the kidney of the sacrificed mice. 80% of mice survived after KET therapy. However, C. albicans was present in the kidney in an amount of 105−106 CFU/g of tissue. C. albicans did not reappear in the kidney 7 days after the discontinuation of APB treatment, but it was found there after KET therapy.  相似文献   

6.
Abstract

Objective: In this study, attempt has been focused to prepare a nanoemulsion (NE) gel for topical delivery of amphotericin B (AmB) for enhanced as well as sustained skin permeation, in vitro antifungal activity and in vivo toxicity assessment.

Materials and methods: A series of NE were prepared using sefsol-218 oil, Tween 80 and Transcutol-P by slow spontaneous titration method. Carbopol gel (0.5%?w/w) was prepared containing 0.1%?w/w AmB. Furthermore, NE gel (AmB-NE gel) was characterized for size, charge, pH, rheological behavior, drug release profile, skin permeability, hemolytic studies and ex vivo rat skin interaction with rat skin using differential scanning calorimeter. The drug permeability and skin irritation ability were examined with confocal laser scanning microscopy and Draize test, respectively. The in vitro antifungal activity was investigated against three fungal strains using the well agar diffusion method. Histopathological assessment was performed in rats to investigate their toxicological potential.

Results and discussion: The AmB-NE gel (18.09?±?0.6?µg/cm2/h) and NE (15.74?±?0.4?µg/cm2/h) demonstrated the highest skin percutaneous permeation flux rate as compared to drug solution (4.59?±?0.01?µg/cm2/h) suggesting better alternative to painful and nephrotoxic intravenous administration. Hemolytic and histopathological results revealed safe delivery of the drug. Based on combined results, NE and AmB-NE gel could be considered as an efficient, stable and safe carrier for enhanced and sustained topical delivery for AmB in local skin fungal infection.

Conclusion: Topical delivery of AmB is suitable delivery system in NE gel carrier for skin fungal infection.  相似文献   

7.
The purpose of this study was to evaluate the in vitro and in vivo antitumor efficacy and the dose dependent toxicity of camptothecin nanosuspension (Nano-CPT) comparing with that of topotecan (TPT). A novel supercritical antisolvent (SAS) process-high pressure homogenization technique has been developed to prepare Nano-CPT. The cytotoxicity of Nano-CPT and TPT was investigated against MCF-7, HCT-8, and PC-3 cell lines using MTT assay, antitumor activity in vivo were evaluated against HCT-8 xenograft model, and the dose dependent toxicity in vivo during the treatment were investigated by body weight changes and relative organ weight variations. The Nano-CPT presents about 6 times in vitro cytotoxicity active than TPT against cell lines MCF-7, nearly the same in vivo antitumor activity with TPT and lower toxicity. The results confirm that Nano-CPT is a novel potential formulation with high antitumor efficacy and low toxicity.  相似文献   

8.
The study aimed to formulate and evaluate levofloxacin hemihydrate ocular in situ gels along with freshly prepared disappearing preservative reported to be safer to human eyes. Formulae were prepared using thermosensitive (PF127 and PF68) or ion-activated (Gelrite) polymers. They were evaluated for gelation temperature (GT), capacity, content uniformity, pH, rheological behavior, in vitro drug release with kinetic analysis. Best formulae were exposed to storage effect to select the optimum formula that was subjected to different sterilization methods and in vivo evaluation. The prepared disappearing preservative (sodium perborate monohydrate) proved to be active oxidative preservative and compatible with our formulae. F9 (24% PF127, 15% PF 68, 0.5% levofloxacin hemihydrate, and 0.0025% sodium perborate monohydrate) showed prolonged drug release (12?h), acceptable GT, viscosity, and pH. It remained stable over 3 months at two temperatures and was best sterilized by filtration. It showed longer residence time (12?h) in rabbits’ eye fluids compared with the Levoxin® eye drops (4?h). This successful attempt of using thermo-gelling system along with a disappearing type of preservatives would allow the use of these systems to achieve sustained release of antimicrobial drugs with minimum risk of eye damage improving patient compliance and treatment efficacy.  相似文献   

9.
Literature reports suggest that pyrazoles and hydrazides are potential antimicrobial pharmocophores. Considering this fact, a series of nineteen conjugates containing hybrids of bis‐pyrazole scaffolds joined through a hydrazide linker were synthesized and further evaluated for their antimicrobial activity against a panel of Gram‐positive and Gram‐negative bacteria along with Candida albicansMTCC 3017 strain. Although the derivatives exhibited good antibacterial activity, some of the derivatives ( 13d , 13j , 13l , 13p , and 13r ) showed excellent anti‐Candida activity with MICs values of 3.9 μg/ml, which was equipotent to that of the standard Miconazole (3.9 μg/ml), which has inspired us to further explore their anti‐Candida activity. The same compounds were also tested for anti‐biofilm studies against various Candida strains and among them, compounds 13l and 13r efficiently inhibited the formation of fungal biofilms. Field emission scanning electron micrographs revealed that one of the promising compound 13r showed cell damage and in turn cell death of the Candida strain. These potential conjugates ( 13l and 13r ) also demonstrated promising ergosterol biosynthesis inhibition against some of the strains C. albicans, which were further validated through molecular docking studies. In silico computational studies were carried out to predict the binding modes and pharmacokinetic parameters of these conjugates.  相似文献   

10.
目的评估多支链的阳离子高分子聚合物——聚乙烯亚胺(PEI)单独及与三种不同类别的常规抗菌药物(两性霉素B、氟康唑和多黏菌素B)联合使用对白念珠菌(MY7245和MY7238)的两种临床分离物的抗真菌活性。方法通过体外实验测定不同分子质量聚乙烯亚胺单独及与三种不同类别的常规抗菌药物联合使用对两株白念珠菌的最小抑菌浓度和杀灭时间,确定PEI单独及联合使用的体外抗真菌活性。结果分子量在2~745ku范围内的PEI均对这两种白念珠菌产生很好的抗真菌活性,且分子量小的PEI比分子量大的PEI的抗菌作用更显著。与单独作用的PEI相比,分子量较大的PEI与常规药物联合使用时可产生较强的协同作用。在体外致死研究实验中可以看到,PEI-两性霉素B和PEI-氟康唑结合物可以提高抑菌作用,但PEI-多黏菌素B结合物却拮抗抑菌作用。结论PEI单独与联合使用均对白念珠菌产生很好的抗菌效果。  相似文献   

11.
目的考察注射用头孢唑林钠(CS)与脂肪乳配伍时的稳定性及配伍后在体内外的抑菌活性。方法分别利用pH计和动态光散射粒径仪检测CS与脂肪乳配伍液在25℃和4℃下24 h内的pH值和粒径的变化情况,采用HPLC法检测配伍液中药物的含量变化情况,采用微量液体稀释法考察配伍液的体外抑菌活性,考察CS(900、300、100 mg·kg~(-1))分别与生理盐水及10%脂肪乳配伍后对金黄色葡萄球菌感染小鼠存活率的影响。结果 CS分别与10%、20%和30%脂肪乳配伍后,脂肪乳的外观、pH值、粒径、含量均无明显改变(P>0.05)。CS-10%脂肪乳、CS-20%脂肪乳和CS-30%脂肪乳对大肠杆菌的最低抑菌浓度分别为1、0.5、0.5 mg·L~(-1),与CS(2 mg·L~(-1))相比无显著差异(P>0.05);对金黄色葡萄球菌的最低抑菌浓度分别为0.25、0.25、0.25 mg·L~(-1),与CS(0.5 mg·L~(-1))相比无显著差异(P>0.05)。CS 300 mg·kg~(-1)与10%脂肪乳配伍后对金黄色葡萄球菌的体内抑菌作用(小鼠7 d存活率40%)优于用生理盐水稀释(小鼠7 d存活率20%)(P<0.01)。结论 CS在分别与10%、20%和30%脂肪乳配伍时稳定性良好,与10%脂肪乳配伍对体内外抑菌效果也无影响。  相似文献   

12.
目的评价柏黛膏抗菌活性及其与青霉素的协同抑菌效能。方法最低抑菌浓度(MIC)测定用琼脂二倍稀释法。结果柏黛膏与青霉素对金黄色葡萄球菌与大肠杆菌具有很好的抗菌活性,柏黛膏+青霉素对金黄色葡萄球菌与大肠杆菌抗菌MIC50和MIC90值分别为0.25,4.00 mg.L-1;1,4 mg.L-1。结论柏黛膏与青霉素对金黄色葡萄球菌、大肠杆菌均有协同抗菌功效。  相似文献   

13.
目的 :了解帕尼培南 倍他米隆对临床常见致病菌的体外抗菌活性及治疗肺部感染的有效性及安全性。方法 :采用琼脂二倍稀释法测定帕尼培南 倍他米隆对 2 4 7株临床分离菌的MIC ,检测其对部分菌株的最低杀菌浓度 ;2 0例肺部感染病人使用帕尼培南 倍他米隆 5 0 0 /5 0 0mg ,q 12h ,iv ,gtt ,疗程3~ 7d。结果 :帕尼培南 倍他米隆与帕尼培南的体外抗菌活性基本一致 ,MIC50 ≤ 0 .0 0 75mg·L- 1,MIC90 为 0 .0 0 75~ 2mg·L- 1;对流感嗜血杆菌的MIC范围为 <0 .0 0 75~ 0 .12 5mg·L- 1;对阴沟肠杆菌、变形肠杆菌、铜绿假单孢菌的MIC50 和MIC90 分别为 0 .12 5和 0 .5 ,2和 4 ,4和 16mg·L- 1;帕尼培南 倍他米隆对金黄色葡萄球菌、表皮葡萄球菌、铜绿假单孢菌、肺炎克雷伯菌、大肠埃希菌、阴沟肠杆菌、变形肠杆菌及微球菌的最低杀菌浓度分别是其MIC的 1~ 8倍。致病菌阴转率为 77.8% ,治疗有效率为 75 % ,未出现明显不良反应。结论 :帕尼培南 倍他米隆对临床常见致病菌的体外抗菌活性强 ;对肺部感染有较好疗效 ,安全性好  相似文献   

14.

Background and purpose:

Many bromopyrrole compounds have been reported to have in vitro antineoplastic activity. In a previous study, we isolated N-(4, 5-dibromo-pyrrole-2-carbonyl)-L-amino isovaleric acid methyl ester (B6) from marine sponges. Here, we investigated the in vitro and in vivo antineoplastic activity of B6 and its potential mechanism.

Experimental approach:

The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to determine the in vitro antineoplastic activity of B6. Flow cytometry, western blot analysis and morphological observations were used to investigate its mechanism of action. A mouse xenograft model was used to determine its in vivo activity.

Key results:

B6 inhibited the proliferation of various human cancer cells in vitro, with highest activity on LOVO and HeLa cells. B6 also exhibited significant growth inhibitory effects in vivo in a xenograft mouse model. Acute toxicity analysis suggested that B6 has low toxicity. B6-treated cells arrested in the G1 phase of the cell cycle and had an increased fraction of sub-G1 cells. In addition, the population of Annexin V-positive/propidium iodide-negative cells increased, indicating the induction of early apoptosis. Indeed, B6-treated cells exhibited morphologies typical of cells undergoing apoptosis. Western blotting showed cleaved forms of caspase-9 and caspase-3 in cells exposed to B6. Moreover, B6-promoted Ca2+ release and apoptosis was associated with elevated intracellular Ca2+concentration.

Conclusions and implications:

B6 has significant antineoplastic activity in vitro as well as in vivo. It inhibits tumour cell proliferation by arresting the cell cycle and inducing apoptosis. With its low toxicity, B6 represents a promising antineoplastic, primary compound.  相似文献   

15.
16.
CL 284,846, N-[3-3-cyanopyrazolo[1,5-a]pyrimidin-7-yl(phenyl)]-N-ethylacetamide, is a novel non-benzodiazepine sedative-hypnotic with benzodiazepine-like sedative effects, but with less apparent liability for accompanying undesired side effects. Three metabolites of the parent sedative-hypnotic have been isolated and identified, a desethyl metabolite, CL 284,859, a desethyl-5-keto metabolite, CL 345,644, and a 5-keto metabolite, CL 345,905. In experiments to determine the ability of these compounds to displace [3H]-flunitrazepam from rat cortical benzodiazepine receptors, the IC50 values were 205 nM for CL 284,846 compared to 4.5 nM for diazepam as a positive control, and 11 μM for CL 284,859. The other two metabolite, CL 345,644 and CL 345,905, failed to displace [3H]-flunitrazepam. In a second experiment designed to evaluate in vivo receptor-mediated activity, CL 284,846 (3.0 mg/kg; 9.836 μmol/kg) was established as a discriminative stimulus (DS) in rats. While CL 284,846 (0.03ndash;3.0 mg/kg; 0.098–9.836 μmol/kg) showed a doserelated increase in drug-appropriate responding and one dose of triazolam (0.3 mg/kg; 0.875 μmol/kg) substituted as a positive control, all three metabolites (3.0–100.0 mg/kg; 10.3–341.3 μmol/kg for CL 284,859; 6.0–201.2 μmol/kg for CL 345,644; 9.3–311.5 μmol/kg for CL 345,905) failed to substitute for the DS effects of CL 284,846. These results suggest that CL 284,859, CL 345,644, and CL 345,905, the metabolites of the sedative-hypnotic CL 284,846, have no significant neuropharmacological effects at central benzodiazepine receptors and, thus, do not contribute to the activity of the parent compound. © 1994 Wiley-Liss, Inc.  相似文献   

17.
《Pharmaceutical biology》2013,51(3):338-343
Context: In India, Dregea volubilis (L.f.) Benth. ex Hook.f. (Asclepediaceae), a large twining shrub with a woody vine, is used to treat tumors traditionally.

Objective: This study evaluated the in vitro and in vivo antitumor activity of the methanol extract of Dregea volubilis leaves (MEDV) and elucidated its possible mechanism of action.

Materials and methods: In vitro antitumor activity of MEDV was evaluated against Ehrlich ascites carcinoma (EAC) cell-line. In vivo antitumor and antioxidant activity of MEDV at three dose levels (50, 100, and 200?mg/kg) were determined against EAC tumor-bearing mice. After 24?h of EAC inoculation, the extract was administered for 9 consecutive days. After the administration of the last dose on the 9th day followed by 18?h fasting, mice from all groups were sacrificed to determine antitumor activity and hematological profiles along with liver related biochemical parameters like lipid peroxidation, antioxidant enzymatic activity, etc.

Results: For in vitro antitumor activity, IC50 value of MEDV for EAC tumor cells was 85.51?±?4.07 µg/ml. The MEDV showed a decrease in tumor volume, packed cell volume and viable cell count and an increase in the non-viable cell count of the EAC tumor-bearing mice (p?<?0.001). Hematological profile reverted near to normal level in extract treated mice. MEDV decreased the hepatic lipid peroxidation level and enhanced superoxide dismutase and catalase level in tumor-bearing mice (p?<?0.001).

Discussion and conclusion: MEDV exhibited in vitro and in vivo antitumor activity in EAC tumor-bearing mice mediated through augmenting antioxidant defense system.  相似文献   

18.
This multicentre, double-blind, double-dummy, randomised study was undertaken to compare the efficacy and tolerability of famciclovir administered at 250 mg, 500 mg and 750 mg three times daily with acyclovir 800 mg five times daily for the treatment of acute uncomplicated herpes zoster in immunocompetent adults. A total of 545 patients participated in this trial. Treatment was initiated within 72 h of the onset of the zoster rash and was continued for seven days. When treatment was initiated within 72 h, famciclovir was found to be as effective as acyclovir at all dose levels for cutaneous lesion healing as demonstrated by the median times to full crusting, cessation of new lesion formation, loss of vesicles and loss of crusts; time to loss of acute pain was comparable in patients receiving famciclovir and acyclovir. Time to resolution of zoster-associated pain, however, occured at a significantly faster rate in patients treated with famciclovir within 48 h of rash onset compared with acyclovir treatment. Famciclovir was well tolerated with a safety profile comparable to that of acyclovir. Gastrointestinal disturbances and headache were the most common adverse experiences in all treatment groups. In conclusion, famciclovir, administered less frequently and at lower unit doses than acyclovir, is an effective treatment for patients with uncomplicated herpes zoster.  相似文献   

19.
Summary Intoplicine (RP 60475, NSC 645008) is a new 7H-benzo[e]pyrido[4,3-b] indole derivative which interacts with DNA and inhibits both topoisomerases I and II.In vitro it was found cytotoxic against various cell types with greater cytotoxicity towards solid tumor cells. We report here the anticancer activity of RP 60475 against a variety of transplantable tumors of mice, and also its cross-resistance profile in leukemias. The end points used were % T/C (median tumor weight of the Treated over the Control × 100) and logCK (log10 cell kill total). RP 60475 administered i.v. was found schedule-independent with a peak plasma level problem. It had a good therapeutic index and host recovery usually occurred 7.5 days post last treatment. RP 60475 was found to be highly active against early stage colon 38 (T/C=0%, 2.9 logCK) and could induce 5/5 complete regressions of advanced stage tumor. It was found active against colon adenocarcinoma 51 (T/C=3.6%, 1.9 logCK) and colon carcinoma 26 (T/C=11.7%, 1.2 logCK). Most of the mammary adenocarcinomas were found very responsive, MA16/C (T/C=0%, 2.8 logCK), MA14/A (T/C=0%, 1.4 logCK), MA13/C (T/C=0%, 3.1 log CK) and MA44 (T/C=34%). Excellent activity was also observed against early stage pancreatic ductal adenocarcinoma 03 (T/C=0%) and RP 60475 could achieve 5/5 complete regressions of upstaged tumor. Activity was also obtained on Glasgow osteogenic sarcoma (T/C=0%, 3.3 logCK), on B16 melanoma (T/C=14%, 1.3 logCK) and to a lesser extent on Lewis lung carcinoma (T/C=33.2%). Evaluation of RP 60475 against leukemia sublines with acquired resistance, revealed that L1210/cisplatin and L1210/BCNU were not cross-resistant to RP 60475 whereas P388/vincristine was partially cross-resistant to RP 60475 and P388/doxorubicin was cross-resistant to RP 60475. Based on RP 60475 broad activity against transplantable tumors of mice, its effectiveness against some resistant sublines, its original mechanism of action and its acceptable toxicological profile, this compound was selected for clinical trials.  相似文献   

20.
Summary Two new aromatic bis-(2-chloroethyl)-amino derivatives (BCMP and BAD) which are linked to osteotropic bisphosphonates were investigated for their therapeutical efficacy in rat osteosarcoma. Furthermore their genotoxic potential in vitro was determined in S. typhimurium and in mammalian cells. Finally, parameters for toxicity and genotoxicity were determined in liver and bone marrow cells following in vivo treatment. It was shown that BAD was of higher therapeutic effectiveness than BCMP. Both compounds induced approximately a two fold increase of his+ revertants in S. typhimurium TA1535 following metabolic activation by subcellular liver fractions. Both compounds also induced amplification of SV40 DNA in SV40 transformed cells (CO631). This endpoint may be of importance for acquired resistancy of cells during therapy. DNA-single strand breaks were induced by BCMP but not by BAD in liver cells and CO631 cell line. Following in vivo treatment BCMP was of higher genotoxic activity in liver cells than BAD. In comparison, genotoxicity of both compounds was much lower in bone marrow cells than in liver cells. BCMP was again more potent than BAD in inducing DNA single strand breaks, whereas BAD was more toxic. The higher therapeutic efficacy of BAD together with its lower genotoxic properties makes this compound superior to BCMP as a candidate for applied chemotherapy in humans.  相似文献   

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