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1.
2.
The Authors have conducted the experimental studies tending to valuate the antibacterial activity in vitro and in vivo of cinoxacin versus that demonstrated by nalidixic acid. The obtained results demonstrate the cinoxacin presents a similar antibacterial activity to that of nalidixic acid.  相似文献   

3.
We studied the effect of partial retro-inverso modification of selected peptide bonds of dermorphin (H-Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2. The modifications concern two consecutive peptide bonds (Phe3-Cly4-Tyr5, I) or a single one (Gly4-Tyr5-, II or Phe3-Gly4, III). All pseudoheptapeptides showed low opioid activity in the in vitro and in vivo tests. Compound III has a biological potency comparable to that of morphine but only 2-5% of original dermorphin when tested in guinea pig ileum preparation and in mice tail-flick assay after intracerebro or subcutaneous administration.  相似文献   

4.
Brassinosteroids are a novel group of steroids that appear to be ubiquitous in plants and are essential for normal plant growth and development. It has been previously reported that brassinosteroid analogues exert an antiviral activity against herpes simplex virus type 1 (HSV-1) and arenaviruses. In the present study, we report the chemical synthesis of compounds (22S,23S)-3beta-bromo-5alpha,22,23-trihydroxystigmastan-6-one (2), (22S,23S)-5alpha-fluoro-3beta-22,23-trihydroxystigmastan-6-one (3), (22S,23S)-3beta,5alpha,22,23-tetrahydroxy-stigmastan-6-one (4) as well as their antiherpetic activity both in a human conjunctive cell line (IOBA-NHC) and in the murine herpetic stromal keratitis (HSK) experimental model. All compounds prevented HSV-1 multiplication in NHC cells in a dose dependent manner when added after infection with no cytotoxicity. Administration of compounds 2, 3, and 4 to the eyes of mice at 1, 2, and 3 days post-infection delayed and reduced the incidence of HSK, consisting mainly of inflammation, vascularization, and necrosis, compared to untreated, infected mice. However, viral titers of eye washes showed no differences among samples from treated and untreated mice. Since the decrease in the percentage of mice with ocular lesions occurred 5 days after treatment had ended, we suggest that brassinosteroids 2, 3, and 4 did not exert a direct antiviral effect in vivo, but rather may play a role in immune-mediated stromal inflammation, which would explain the improvement of the clinical signs of HSK observed.  相似文献   

5.
A series of 3,6-epoxy [1,5]dioxocines were synthesized and evaluated for their antifilarial activity against adult parasites of human lymphatic filarial parasite Brugia malayi (sub-periodic strain) in vitro. Out of these, six compounds (4a-f) possessed improved in vitro anti-filarial activity and examples 4d and 4f were also found to be active in the in vivo experiments. These results demonstrate that 3,6-epoxy [1,5]dioxocines exhibits potent antifilarial activity and might be developed into a new class of antifilarial drug.  相似文献   

6.
The biological activities of des-octapeptide-insulin, des-AsnA21-des-AlaB30-insulin, des-GlyA1-des-PheB1-insulin and trimethionyl-insulin were studied in vitro and in vivo. In vitro we measured, using the isolated diaphragm of the rat, the disappearance rate of glucose in the incubation medium, the incorporation of glucose into the glycogen of the diaphragm and the apntilipolytic activity in the isolated fat cell model. The incorporation of [U-14C]glucose after intraperitoneal injection into the glycogen of the diaphragm and the fat pad tissue was studied in vivo, as well as the incorporation of 14C from [U-14C]glucose into the lipids of the fat pad tissue of the rat.  相似文献   

7.
8.
Nitroarylidenemalononitriles and their cyanoacetamide derivatives with remarkable anti-epimastigote properties, were synthesized attempting to obtain new 3,5-diamino-4-(5'-nitroarylidene)-4H-thiadiazine 1,1-dioxide derivatives, which in previous reports had shown anti-Trypanosoma cruzi activity. Tests to evaluate the cytotoxicity of compounds were performed on J774 macrophages. 5-nitro-2-thienyl-malononitrile (5NO2TM), was the only product which maintained a high anti-epimastigote activity at concentrations in which it was no longer cytotoxic, thus it was assayed against intracellular amastigotes. Its anti-amastigote activity was similar to that of nifurtimox. Afterwards in vivo toxicity and anti-chagasic activity were determined. A reduction in parasitemia was observed.  相似文献   

9.
The naturally occurring amphibian skin peptides dermorphin (Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2) and dermenkephalin (Tyr-D-Met-Phe-His-Leu-Met-Asp-NH2) are highly potent and selective agonists at the mu- and the delta-opioid receptors, respectively. For peptides synthesized by animal cells, they have a rather peculiar structural feature of containing a D-amino acid residue in their sequence which imparts biological activity on them. The cloned cDNA encoding the prodermorphin precursor contains the usual alanine and methionine codons at positions where D-alanine and D-methionine are present in the mature products. In this study, dermorphin precursor was characterized in extracts from amphibian skin by antisera recognizing distinct epitopes within the predicted structure of pro-dermorphin. Proteolytic digestion of purified endogenous pro-dermorphin generated a peptide containing a D-alanine in position 2, identified as prepro-dermorphin-(80-89), i.e. Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-Gly-Glu-Ala. In addition, analysis of skin extracts by enzyme immunoassays coupled to high performance liquid chromatography separations revealed the presence of, besides dermenkephalin, novel dermenkephalin-related peptides, i.e. [L-Met2]dermenkephalin, dermenkephalin-OH, and [Met(O)6]dermenkephalin. [L-Met2]dermenkephalin was present in frog skin in a concentration of about 100 times that of dermenkephalin. These observations confirm that, despite the presence of D-amino acid residues, dermorphin and dermenkephalin are genuine products of post-translational processing of a ribosomally made precursor. They suggest that D-Ala and D-Met develop from a dehydrogenation/hydrogenation stereoinversion of their corresponding L isomers incorporated into pro-dermorphin, a process that occurs with low efficiency at an early stage of biosynthesis.  相似文献   

10.

Background

Antitumor cyclopalladated complexes with low toxicity to laboratory animals have shown leishmanicidal effect. These findings stimulated us to test the leishmanicidal property of one palladacycle compound called DPPE 1.2 on Leishmania (Leishmania) amazonensis, an agent of simple and diffuse forms of cutaneous leishmaniasis in the Amazon region, Brazil.

Methodology/Principal Findings

Promastigotes of L. (L.) amazonensis and infected bone marrow-derived macrophages were treated with different concentrations of DPPE 1.2. In in vivo assays foot lesions of L. (L.) amazonensis-infected BALB/c mice were injected subcutaneously with DPPE 1.2 and control animals received either Glucantime or PBS. The effect of DPPE 1.2 on cathepsin B activity of L. (L.) amazonensis amastigotes was assayed spectrofluorometrically by use of fluorogenic substrates. The main findings were: 1) axenic L. (L.) amazonensis promastigotes were destroyed by nanomolar concentrations of DPPE 1.2 (IC50 = 2.13 nM); 2) intracellular parasites were killed by DPPE 1.2 (IC50 = 128.35 nM), and the drug displayed 10-fold less toxicity to macrophages (CC50 = 1,267 nM); 3) one month after intralesional injection of DPPE 1.2 infected BALB/c mice showed a significant decrease of foot lesion size and a reduction of 97% of parasite burdens when compared to controls that received PBS; 4) DPPE 1.2 inhibited the cysteine protease activity of L. (L.) amazonensis amastigotes and more significantly the cathepsin B activity.

Conclusions/Significance

The present results demonstrated that DPPE 1.2 can destroy L. (L.) amazonensis in vitro and in vivo at concentrations that are non toxic to the host. We believe these findings support the potential use of DPPE 1.2 as an alternative choice for the chemotherapy of leishmaniasis.  相似文献   

11.
Kim SN  Bae SJ  Kwak HB  Min YK  Jung SH  Kim CH  Kim SH 《Amino acids》2012,42(4):1455-1465
We investigated the in vitro and in vivo osteogenic activity of licochalcone A. At low concentrations, licochalcone A stimulated the differentiation of mouse pre-osteoblastic MC3T3-E1 subclone 4 (MC4) cells and enhanced the bone morphogenetic protein (BMP)-2-induced stimulation of mouse bi-potential mesenchymal precursor C2C12 cells to commit to the osteoblast differentiation pathway. This osteogenic activity of licochalcone A was accompanied by the activation of extracellular-signal regulated kinase (ERK). The involvement of ERK was confirmed in a pharmacologic inhibition study. Additionally, noggin (a BMP antagonist) inhibited the osteogenic activity of licochalcone A in C2C12 cells. Licochalcone A also enhanced the BMP-2-stimulated expression of various BMP mRNAs. This suggested that the osteogenic action of licochalcone A in C2C12 cells could be dependent on BMP signaling and/or expression. We then tested the in vivo osteogenic activity of licochalcone A in two independent animal models. Licochalcone A accelerated the rate of skeletal development in zebrafish and enhanced woven bone formation over the periosteum of mouse calvarial bones. In summary, licochalcone A induced osteoblast differentiation with ERK activation in both MC4 and C2C12 cells and it exhibited in vivo osteogenic activity in zebrafish skeletal development and mouse calvarial bone formation. The dual action of licochalcone A in stimulating bone formation and inhibiting bone resorption, as described in a previous study, might be beneficial in treating bone-related disorders.  相似文献   

12.
The non-steroidal antiinflammatory drug diclofenac sodium exhibited remarkable inhibitory action against both drug sensitive and drug resistant clinical isolates of Mycobacterium tuberculosis, as well as other mycobacteria. This agent was tested in vitro against 45 different strains of mycobacteria, most of which were inhibited by the drug at 10-25 microg/ml concentration. When tested in vivo, diclofenac, injected at 10 mg/kg body weight of a Swiss strain of white mice, could significantly protect them when challenged with a 50 median lethal dose of M. tuberculosis H37 Rv102. According to Chi-square test, the in vivo data were highly significant (P<0.01).  相似文献   

13.
Factors affecting multilamellar vesicles transport to the blood compartment after oral administration to rats were evaluated first in vitro. A high entrapment of protein A was obtained when the vesicles were prepared by shearing a lyotropic lamellar phase composed of soybean phosphatidylcholine, cholesterol and polyoxyethylene alcohol (C12H25(OCH2CH2)4OH) as neutral detergent. In vitro tests showed that these vesicles (spherulites) were stabled in 50% of fetal calf serum, in acidic (pH 3) or basic (pH 10) buffers, in pancreatin but are partially lysed in 20mM bile salts. Oral administration of spherulites entrapping 111In-NTA in fasting rats showed a increase of radioacticivity in blood. This could be explained by passage of some spherulites in the enterocytes.  相似文献   

14.
Mouse monoclonal antibodies to CD19 detect an antigenic determinant expressed exclusively on the surface of B lymphocytes, and have previously been shown to be potentially useful therapeutic reagents for human B cell lymphoma. We report the production and characterization of a mouse/human chimeric antibody, cCD19, with potent in vivo antitumour activity. The genes encoding the variable domains for heavy (VH) and light (VL) chains were subcloned into eukaryotic expression vectors containing human constant region genes (IgG1 and ), and co-transfected into non-secreting Sp2/0 mouse myeloma cells. Intraperitoneal administration of cCD19 produced inhibition of growth of subcutaneous CD19+ Sultan human B lymphoma tumours inscid/scid mice. When the antibody was administered 18 and 20 days after subcutaneous tumour inoculation, an approximately 30% reduction in tumour size was noted by day 29. cCD19 faithfully mimicked the in vitro binding characteristics of mCD19 as (a) the chimeric antibody was shown by flow cytometry to bind exclusively to cell lines that expressed CD19, (b) cCD19 was able to inhibit the binding of mCD19 on CD19+ cells completely and (c) the affinity of binding of the two antibodies was not significantly different [K a=(2.03±1.5)×108]. In biodistribution studies, up to 14.8% of the total injected antibody dose per gram of tissue was localized in CD19+ Sultan tumours at 24 h approximately, 14.4% was present in the tumors at 48 h and about 13.7% at 72 h. These levels were comparable to mCD19 administered in the same fashion. cCD19 conjugated to idarubicin was specifically and strongly cytotoxic to CD19+ cells cultured in vitro, and demonstrated an IC50 of 0.17 M, similar to that of mCD19 (0.32 M) and approximately 14-fold greater than the IC50 of free idarubicin. The specific cytotoxic capacity of cCD19 and its likely reduced immunogenicity suggest that it may potentially be of use in the treatment of refractory B cell lymphoma in humans.  相似文献   

15.
In vitro and in vivo DNA bonding by the CC-1065 analogue U-73975   总被引:1,自引:0,他引:1  
K L Weiland  T P Dooley 《Biochemistry》1991,30(30):7559-7565
CC-1065, a cyclopropylpyrroloindole (CPI), is a highly potent antitumor DNA-alkylating agent. We have devised a simple method to detect CPI bonding sites on double-stranded DNA (dsDNA). The technique utilizes a modified form of bacteriophage T7 polymerase, Sequenase, to synthesize a radiolabeled nascent strand from dsDNA that has been reacted in vitro with the CC-1065 analogue U-73975 (adozelesin). The reaction products were electrophoresed on sequencing gels containing 8 M urea and visualized by autoradiography. The transit of this DNA polymerase is inhibited at the sites where CPIs are bound to the template strand. Thus, the enzyme stalls or stops at the nucleotide immediately adjacent to the modified base, resulting in the accumulation of DNA strands at these sites and in diminished read-through beyond these sites in a set of CPI-treated DNA molecules. The precise positions of polymerase inhibition can be determined by comparison of CPI-treated and unreacted DNA reactions. This modified dideoxynucleotide sequencing technique has been used to establish the sequence selectivity of U-73975. Approximately 1 kilobase of dsDNA has been analyzed to derive a consensus canonical bonding sequence, 5'(T/A)-T/A-T-A*-(C/G)-(G), where A* is the site of U-73975 alkylation and parentheses denote deoxynucleotide preferences. Noncanonical sites were also found at poly(A) sites. This technique yielded a consensus sequence for U-73975 bonding that is similar to, but not identical with, the published consensus obtained for CC-1065 by a modified Maxam and Gilbert sequencing technique. We have also examined the bonding of [3H]U-73975 to the DNA of viable cultured mammalian cells, using gel electrophoresis and autoradiographic techniques.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
A series of hepta-, hexa-, penta- and tetrapeptide analogues of dermorphin have been evaluated in the rat for antinociceptive activity after subcutaneous (SC) administration at the screening dose of 4 mg/kg. Effective doses (ED50) were calculated for the most active compounds. Presence of spontaneous movements, defecation, micturition and corneal reflex were also recorded. Syntheses and analytical data of new derivatives are briefly reported.  相似文献   

17.
Chang-lin Wang  Chao Guo  Ying Zhou  Rui Wang   《Peptides》2009,30(9):1697-1704
Previously, we have synthesized a series of endomorphin-2 (EM-2) analogs by the substitution of C-terminal amide group. In the present study, to further our knowledge of the influence of C-terminal esterified modification on the pharmacological activities, we investigated the in vitro and in vivo opioid activities of C-terminal esterified EM-2 analogs 13. Our results showed that the ED50 values on contractions of the longitudinal muscle of distal colon induced by analogs 13 were about 1.5-fold higher, 2- and 8-fold lower than EM-2, respectively. In addition, intravenous (i.v.) injections of analogs 1 and 2 dose-dependently decreased the system arterial pressure (SAP) and heart rate (HR) in anesthetized rats, but the degree of the hypotension and bradycardia was significantly smaller relative to the parent. Moreover, analog 3 was almost ineffective. Nevertheless, all these analogs produced potent antinociception in the tail-flick test after intracerebroventricular (i.c.v.) injection, and this antinociception was inhibited by naloxone, indicating an opioid mechanism. In summary, these results gave the evidence that the conversion of C-terminal amide to esterified modification may play an important role in the regulation of opioid affinities and pharmacological activities.  相似文献   

18.
An endocrinologically-potent octapeptide analogue of somatostatin (SRIF), 3-(2-naphthyl)-D-Ala-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH2 (BIM-23014 C), was examined for its ability to inhibit the in vitro and in vivo growth of the human small cell lung carcinoma (SCLC) line, NCI-H69. When cultured cells were implanted into athymic nude mice, treatment (500 micrograms/injection, twice daily) resulted in a prolongation of lag time for the appearance of measurable tumors, and there was a marked inhibition of the growth rate. Indeed, peptide injection in the region of the tumor resulted in a complete regression of the NCI-H69 tumors. Withdrawal of BIM-23014 C treatment resulted in an acceleration of tumor growth indicating an antiproliferative rather the oncolytic action. A similar inhibition of tumor growth was also observed when solid tumors obtained from the first implantation were used as the donor tissues. In cell culture, the proliferation in the presence of a low concentration (10nM) of BIM-23104 C was also significantly retarded suggesting a direct mechanism of action.  相似文献   

19.
20.
Summary Pinocytotic activity has been analyzed in Drosophila oocytes following either in vivo or in vitro exposure to horseradish peroxidase. The enzyme tracer gains access to the yolk spheres only when supplied to the oocyte in vivo. In oocytes cultured in vitro, peroxidase remains restricted to the residual coated vesicles and to the tubular profiles formed in excess in the cortical ooplasm.In an attempt to induce peroxidase uptake by oocytes cultured in vitro, various incubations were tested. Among these, hemolymph from both sexes is capable of promoting peroxidase uptake up to a level comparable to that detectable in vivo. On the other hand, fat body extracts fail to promote such cellular activity. Finally, the juvenile hormone analogue ZR-515 is shown to be the only factor required to promote pinocytotic activity under the experimental conditions tested. The observations are interpreted to indicate that vitellogenin has no inductive role on pinocytosis but simply acts by adhering to the forming coated vesicles which in turn are produced by the oolemma in response to the action of juvenile hormone.  相似文献   

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