共查询到20条相似文献,搜索用时 15 毫秒
1.
Sawangjaroen N Phongpaichit S Subhadhirasakul S Visutthi M Srisuwan N Thammapalerd N 《Parasitology research》2006,98(6):588-592
The anti-amoebic activities of chloroform, methanol and water extracts from 12 Thai medicinal plants (39 extracts) commonly used by AIDS patients in southern Thailand were screened, at a concentration of 1,000 μg/ml, against Entamoeba histolytica strain HTH-56:MUTM and strain HM1:IMSS growing in vitro. The extracts were incubated with 2×105
E. histolytica trophozoites/ml of medium at 37°C under anaerobic conditions for 24 h. The cultures were examined with an inverted microscope and scored (1–4) according to the appearance and numbers of the trophozoites. The extracts that caused inhibition were selected and retested using the same conditions but with concentrations that ranged from 31.25 to 1,000 μg/ml using E. histolytica strain HM1:IMSS, and the IC50 values for each extract were calculated. The chloroform extracts from Alpinia galanga (IC50 55.2 μg/ml), Barleria lupulina (IC50 78.5 μg/ml), Boesenbergia pandurata (IC50 45.8 μg/ml), Piper betle (IC50 91.1 μg/ml) and Piper chaba (IC50 71.4 μg/ml) and the methanol extract from B. pandurata (IC50 57.6 μg/ml) were all classified as “active”, i.e. with an IC50 of less than 100 μg/ml, whereas those from Murraya paniculata (IC50 116.5 μg/ml) and Zingiber zerumbet (IC50 196.9 μg/ml) were classified as being “moderately active”. The IC50 of a standard drug, metronidazole, was 1.1 μg/ml. 相似文献
2.
Shuaibu MN Wuyep PA Yanagi T Hirayama K Tanaka T Kouno I 《Parasitology research》2008,102(6):1119-1127
In vitro antiplasmodial activity of methanolic extracts of 16 medicinal plants was evaluated by fluorometric assay using PicoGreen.
The IC50s, as determined by parasite DNA concentration, ranged from <11 to >200 and <13 to >200 μg/ml for Plasmodium falciparum 3D7 and K1, respectively; and the most active extracts were those from Anogeissus leiocarpus and Terminalia avicennoides (<11–≥14 μg/ml). Aqueous, butanolic, ethyl acetate, and methanolic fractions of these two extracts revealed butanolic fraction
to have a relatively better activity (IC50, 10–12 μg/ml). Activity-guided chromatographic separation of the butanolic fraction on Sephadex LH-20 followed by nuclear
magnetic resonance and correlation high-performance liquid chromatography revealed the presence of known hydrolysable tannins
and some related compounds—castalagin, ellagic acid, flavogallonic acid, punicalagin, terchebulin, and two other fractions.
The IC50s of all these compounds ranged between 8–21 μg/ml (8–40 μM) against both the strains. Toxicity assay with mouse fibroblasts
showed all the extracts and isolated compounds to have IC50 ≥ 1500 μg/ml, except for Momordica balsamina with <1500 μg/l. All the extracts and isolated compounds did not affect the integrity of human erythrocyte membrane at the
observed IC50s. However, adverse effects manifest in a concentration-dependent fashion (from IC50 ≥ 500 μg/ml). 相似文献
3.
E. García-Vázquez J. Mensa M. Sarasa Y. López P. D. Couchard D. Soy J. R. Fontenla 《European journal of clinical microbiology & infectious diseases》2007,26(2):137-140
In the study presented here, levofloxacin concentrations in serum samples and the aqueous humour (AH) of 16 patients undergoing
cataract extraction were measured in order to determine the penetration characteristics of levofloxacin into the AH of the
non-inflamed human eye. Cataract removal was performed at various times (from 90 to 270 min) after the end of a 30-min intravenous
infusion of 500 mg of levofloxacin. Serum samples were obtained 1 h after the end of levofloxacin administration (Cmax); AH and a second serum sample were taken simultaneously during the operation, and the concentrations of levofloxacin in
AH (CAH) and serum (CS) were determined using a rapid high-performance liquid chromatography assay. The mean Cmax was 6.07 μg/ml (range 3.75–9.53 μg/ml, SD 1.83). The mean CAH at the first hour following levofloxacin administration was 1.37 μg/ml (range 1.17–1.6 μg/ml, SD 0.22) and the mean ratio
(R=C
AH/CS) was 0.26 (range 0.24–0.3, SD 0.02). The mean C
AH at 125–270 min following levofloxacin administration was 1.39 μg/ml (range 0.82–1.98 μg/ml, SD 0.33) and the mean R was 0.3 (range 0.15–0.53, SD 0.11). Of 16 patients, 15 had a C
AH of >1 μg/ml 1 h after levofloxacin administration. In conclusion, 1 h after administration of 500 mg of levofloxacin, the
levels obtained were higher than the MIC at which 90% of methicillin-susceptible Staphylococcus aureus and certain gram-negative bacteria strains are inhibited.
The abstract and preliminary results of this study were presented at the 7th European Congress of Chemotherapy and Infection,
October 2005, Florence, Italy. 相似文献
4.
Santoro GF das Graças Cardoso M Guimarães LG Salgado AP Menna-Barreto RF Soares MJ 《Parasitology research》2007,100(4):783-790
In the present work, we have investigated the effect of essential oils obtained from Origanum vulgare L. (oregano) and Thymus vulgaris L. (thyme) on growth and ultrastructure of diverse evolutive forms of Trypanosoma cruzi. Culture epimastigotes and bloodstream trypomastigotes were incubated for 24 h with different concentrations of oregano or
thyme essential oils and with thymol (the main constituent of thyme), and the inhibitory concentration (IC)50 was determined by cell counting. Crude extract of oregano essential oil inhibited epimastigote growth (IC50/24 h = 175 μg/ml) and also induced trypomastigote lysis (IC50/24 h = 115 μg/ml). Thyme essential oil presented IC50/24 h values of 77 μg/ml for epimastigotes and 38 μg/ml for trypomastigotes, while treatment with thymol resulted in an IC50/24 h of 62 μg/ml for epimastigotes and 53 μg/ml for trypomastigotes. Scanning electron microscopy of treated cells showed
few morphological alterations at the plasma membrane. Observation by transmission electron microscopy showed cytoplasmic swelling
with occasional morphological alterations in plasma and flagellar membrane. Our data indicate that oregano and thyme essential
oils are effective against T. cruzi, with higher activity of thyme, and that thymol may be the main component responsible for the trypanocidal activity. 相似文献
5.
M. Reichel A. Heisig P. Heisig G. Kampf 《European journal of clinical microbiology & infectious diseases》2010,29(6):623-632
We investigated whether exposure to sub-lethal concentrations of chlorhexidine digluconate (CHG) changed the response of five
Staphylococcus spp. to human β-Defensin-3 (hBD-3). The change in response for each strain was determined in vitro with time–kill experiments
in suspension by comparing the mean log10 reduction caused by hBD-3 at 1.5 and 3 h in exposed and non-exposed bacteria. The identity of staphylococcal species was
verified by DNA sequence homology in the gyrA genes in comparison with reference strains. Baseline sub-lethal concentrations allowing visible bacterial growth were between
0.0625 and 0.25 μg/ml. Sub-lethal CHG concentrations increased within 3 days in two isolates. For S. capitis 19/2, CHG-exposed cells were less susceptible to 0.5 μg/ml hBD-3 (log10 reduction 0.78 versus 2.06 at 1.5 h; p < 0.001; t-test). For S. aureus, however, CHG-exposed cells were more susceptible to 1 μg/ml hBD-3. The observed changes between CHG-exposed and non-exposed
cells did not indicate a general trend in response to hBD-3. Overall, we found no consistent evidence that 3 days of exposure
to CHG changed the response of five Staphylococcus spp. to hBD-3. The use of CHG for skin antisepsis is, based on our data, unlikely to change the natural defence activity
of hBD-3. 相似文献
6.
A. Fenoll M. J. Giménez O. Robledo L. Aguilar D. Tarragó J. J. Granizo J. E. Martín-Herrero 《European journal of clinical microbiology & infectious diseases》2008,27(1):75-80
To study the influence of penicillin/amoxicillin non-susceptibility on the activity of third-generation cephalosporins, 430
consecutive penicillin non-susceptible Streptococcus pneumoniae 2007 isolates received in the Spanish Reference Pneumococcal Laboratory were tested. For comparative purposes, 625 penicillin-susceptible
2007 isolates were also tested. Susceptibility was determined by agar dilution using Mueller-Hinton agar supplemented with
5% sheep blood. Penicillin-susceptible strains were susceptible to amoxicillin, cefotaxime and ceftriaxone, 99.8% to cefpodoxime
and 99.5% to cefdinir, and were inhibited by 0.12 μg/ml of cefditoren and 4 μg/ml of cefixime. Penicillin-intermediate strains
were susceptible to cefotaxime and ceftriaxone, with <50% susceptibility to cefdinir and cefpodoxime. The MIC50 and MIC90 values of cefditoren were 0.25 μg/ml and 0.5 μg/ml, respectively, whereas cefixime exhibited only marginal activity (MIC90=16 μg/ml). Penicillin-resistant strains were resistant to cefdinir and cefpodoxime, with 74.8% and 94.1% susceptibility to
cefotaxime and ceftriaxone, respectively. Cefditoren MIC50/MIC90 (0.5/1 μg/ml) were lower than cefotaxime and ceftriaxone. Among amoxicillin non-susceptible strains, susceptibility to cefdinir
and cefpodoxime was <10%, and susceptibility to cefotaxime decreased from 87.9% in the intermediate category to 63.0% in the
resistant group. Cefditoren MIC50/MIC90 (0.5/1 μg/ml) were lower than cefotaxime. In conclusion, the activity of cefixime, cefdinir and cefpodoxime was highly affected
by penicillin/amoxicillin non-susceptibility, while parenteral third-generation cephalosporins exhibited higher intrinsic
activity (MIC90=1 μg/ml for penicillin-resistant and 2 μg/ml for amoxicillin-resistant strains). Cefditoren exhibited one-dilution lower
MIC90 values for these strains, even against those of the most troublesome serotypes. 相似文献
7.
Pujals G Suñé-Negre JM Pérez P García E Portus M Tico JR Miñarro M Carrió J 《Parasitology research》2008,102(6):1243-1247
The aim of the present study was to evaluate the in vitro activity and cytotoxicity of meglumine antimoniate microspheres
produced by spray drying on Leishmania infantum and the effect of the excipients used in them. The parasite strain shows sensitivity to the meglumine antimoniate microspheres
prepared. All the antimony IC50 values from encapsulated meglumine antimoniate (3.80 ± 0.34 to 9.53 ± 0.70 μg SbV/ml for promastigotes assay) are considerably
lower compared to the mean value of IC50 in Glucantime solution (112 ± 12.74 μg SbV/ml). Interesting IC50 values for the excipient chitosan (112.64 ± 0.53 mg/ml for promastigotes and 100.81 ± 26.45 mg/ml for amastigotes) were obtained
(without cytotoxic activity), whereas the rest of the excipients did not show any activity. This new delivery system could
offer a new pharmacological tool for the treatment of leishmaniosis that reduces the doses required, lowering toxic side effects
because of meglumine antimoniate. 相似文献
8.
Moon HI 《Parasitology research》2007,100(5):1147-1149
Samples of Carpesium genus used as traditional remedies for the treatment of parasite infections were collected, and methanol extracts were obtained
by sonication. The ethylacetate-, n-butanol- and H2O-soluble fractions exhibited weak antiplasmodial activity (IC50 > 100 μg/ml; IC50, 50% inhibitory concentration). However, the chloroform fraction exhibited more impressive antiplasmodial activity (IC50 = 8.2 μg/ml). The antiplasmodial activity of the chloroform fractions was evaluated in vitro against the chloroquine-resistant
D10 strain of Plasmodium falciparum. Bioactivity-guided isolation of the chloroform fractions of the whole plants of Carpesium rosulatum has led to the isolation of a sesquiterpene lactone, ineupatorolides A, displaying high antiplasmodial activity (IC50 = 0.007 μg/ml). This is the first report of the isolation of ineupatorolides A from this species and of its remarkable antiplasmodial
activity. 相似文献
9.
C.-Y. Liu C.-L. Lu Y.-T. Huang C.-H. Liao P.-R. Hsueh 《European journal of clinical microbiology & infectious diseases》2009,28(12):1437-1442
A total of 569 nonduplicate isolates recovered from patients with community-onset or hospital-onset intraabdominal infections
(IAIs) from 2001 to 2006 were studied. These included 28 Staphylococcus aureus and 541 Gram-negative isolates (33.6% Escherichia coli, 29.0% Klebsiella pneumoniae, 8.1% Acinetobacter baumannii, and 6.3% Pseudomonas aeruginosa). Minimum inhibitory concentrations (MICs) of the isolates to moxifloxacin, imipenem, and ciprofloxacin were determined using
the agar dilution method and to tigecycline using the broth microdilution method. Extended-spectrum β-lactamase (ESBL) producers
were found in 15.5% (29 out of 182) of E. coli, 15.3% (24 out of 157) of K. pneumoniae, and 15.4% (2 out of 13) of K. oxytoca isolates. More than 85% of Enterobacteriaceae were susceptible to moxifloxacin, but this percentage was lower among E. coli (78%). The percentage of E. coli (K. pneumoniae) isolates that were not susceptible to moxifloxacin was 6% (0%) in 2001, 39% (17%) in 2003, and 21% (14%) in 2006. Tigecycline
exhibited good in vitro activities against all S. aureus and >95% of all Enterobacteriaceae tested. Among the 24 isolates of ESBL-producing K. pneumoniae, 4 had tigecycline MICs ≥2 μg/ml. Eighty percent of A. baumannii isolates exhibited tigecycline MICs of ≤2 μg/ml. This study found that moxifloxacin and tigecycline exhibited good in vitro
activity against bacterial isolates causing IAIs. 相似文献
10.
K. G. Naber U. Theuretzbacher G. Moneva-Koucheva H. Staß 《European journal of clinical microbiology & infectious diseases》1999,18(11):783-789
Twelve healthy volunteers participated in a randomized crossover study to compare urinary concentrations, serum parameters,
and urinary bactericidal activity of ciprofloxacin after single intravenous (i.v.) doses of 200 mg and 400 mg and an oral
(p.o.) dose of 500 mg. The median serum concentrations at 1 h after administration were 1 μg/ml, 4.3 μg/ml, and 2.2 μg/ml,
respectively. Between the first collection period (0–2 h) and the last collection period (38–48 h), the median urinary concentrations
decreased from 394 μg/ml, 675 μg/ml, and 585 μg/ml, respectively, to 0.3 μg/ml, 0.6 μg/ml, and 1 μg/ml, respectively. The
urinary concentrations after the 400 mg i.v. and the 500 mg p.o. doses were not statistically different but were significantly
higher than those after the 200 mg i.v. dose. The urinary bactericidal titers (UBTs), defined as the highest urinary dilution
bactericidal for the organism tested, were determined against Escherichia coli (ATCC 25922) and eight uropathogens up to 48 h after administration of ciprofloxacin. The UBTs after the 400 mg i.v. and
the 500 mg p.o. doses were similar and were significantly higher (P<0.05) than those following the 200 mg i.v. dose. After 400 mg i.v. and 500 mg p.o., median UBTs of ≥1 : 4 were present up
to 48 h for all strains for which the MIC was ≤0.5 μg/ml, except for one nalidixic-acid resistant Escherichia coli strain for which the MIC was 0.25 μg/ml. Species for which the MIC is ≥1 μg/ml showed median UBTs of ≥1 : 4 for 8–16 h. Median
UBTs of ≥1 : 4 were present up to 8 and 12 h for both Pseudomonas strains tested. A once-daily dosage of 400 mg i.v. or 500 mg p.o. might be sufficient for treatment of urinary tract infections
caused by highly susceptible pathogens. A twice-daily dosing scheme seems to be preferable for complicated infections caused
by pathogens with intermediate susceptibilty (MIC≥1 μg/ml) or for empiric therapy. 相似文献
11.
Yu. V. Zaitseva V. G. Granik A. S. Belik O. A. Koksharova I. A. Khmel 《Molecular Genetics, Microbiology and Virology》2010,25(2):71-76
Nitrofurans (nitrofurazone, nitrofurantoin, furazidin, nifuroxazide) and nitric oxide generators (sodium nitroprusside and
isosorbide mononitrate) in subinhibitory concentrations were shown to significantly increase the bioluminescence of the sensor
Escherichia coli strains used to detect N-acyl-homoserine lactones, which are signal molecules of quorum sensing (QS) regulatory systems. The highest activation of
bioluminescence (up to 250–400-fold) was observed in the presence of the nitrofurazone on E. coli DH5α biosensors containing lux reporter plasmids pSB401 or pSB536. However, this activation was not specifically associated with the functioning of QS systems.
We suggest that the observed effect might be due to the direct action of nitrofurans and NO generators on the bioluminescence
process. The results indicate the need to use biosensors that allow to determine the specific effects of tested substances
on QS regulation. 相似文献
12.
K.-H. Hung J.-J. Yan Y.-C. Lu H.-M. Chen J.-J. Wu 《European journal of clinical microbiology & infectious diseases》2011,30(10):1181-1184
The Clinical Laboratory Standards Institute recommends that if both cefoxitin and oxacillin are tested against Staphylococcus aureus and either result is measured as resistant, the organism should be reported as oxacillin resistant. This indicates that discrepancies
may be present between oxacillin and cefoxitin sensitivities in S. aureus. In this study, we aimed to investigate the discrepancy between oxacillin and cefoxitin susceptibility in S. aureus clinical isolates. Of 10,980 S. aureus isolates recovered from 2005 to 2010, 27 (0.3%) isolates with discordant results between oxacillin and cefoxitin were collected.
Fourteen (oxacillin diameters 10–12 mm) of the 27 strains were susceptible (MICs = 0.5–2 μg/ml) and 13 (6–13 mm) were resistant
(4–>256 μg/ml) to oxacillin. The cefoxitin MICs of 14 oxacillin-susceptible and 13 oxacillin-resistant strains ranged between
4 and 8 and 8 to 32 μg/ml, respectively. Discrepancies were present between oxacillin and cefoxitin in S. aureus, and these strains should be further tested for oxacillin MICs and for the mecA gene or β-lactamase activity. 相似文献
13.
Olounladé PA Azando EV Hounzangbé-Adoté MS Ha TB Leroy E Moulis C Fabre N Magnaval JF Hoste H Valentin A 《Parasitology research》2012,110(4):1427-1433
The need for new anthelmintic with no chemical residues is becoming urgent. In a program aiming at the evaluation of plant
as sources of new active molecules, the anthelmintic activities of the essential oils (EOs) obtained from either Zanthoxylum zanthoxyloides seeds or Newbouldia laevis leaves were evaluated against Strongyloides ratti by analyzing the results of two in vitro bioassays. These two plants and their tested parts were retained after an ethnopharmacology
survey that confirmed their use by small-scale farmers for treatment of small ruminants affected by digestive helminths. The
plants were harvested in Benin, and their EO were obtained by hydrodistillation. The EO yield of extraction was 0.65% (w/w)
of for Z. zanthoxyloides seeds and 0.05% (w/w) for N. laevis. The chemical compositions of the two EOs were analyzed by gas chromatography coupled with mass spectrometry. The major constituents
of the EO from Z. zanthoxyloides consisted of the following compounds: γ-terpinene (18 %), undecane (15 %), valencene (8.3 %), decanal (8.3 %), and 3-carene
(6.7 %). In contrast, the major constituents of the EO from N. laevis leaves consisted of the following compounds: β-caryophyllene (36 %) and eugenol (5.8 %). An egg-hatching inhibition (EHI)
assay was developed and a larval migration inhibition assay was used on S. ratti to examine the effects of the EOs and to evidence their inhibitory concentrations (IC50 and IC90) values on this nematode. Furthermore, the toxicity of the two EOs on Vero cell line was evaluated. When tested on S. ratti egg hatching, the two EOs resulted in similar IC50 values (19.5 and 18.2 μg/ml for Z. zanthoxyloides and N. laevis, respectively), which were about sevenfold higher than that of the control (thiabendazole, IC50 = 2.5 μg/ml). Larval migration was inhibited at similar concentrations for: Z. zanthoxyloides (IC50 = 46 μg/ml), N. laevis (IC50 = 51 μg/ml), and the control [levamisole (IC50 = 36 μg/ml)]. No cytotoxicity was found on Vero cells because both EOs had IC50 values higher than 50 μg/ml. Therefore, we have concluded that the EOs from two plants, used in folk medicine, may contain
compounds with anthelmintic activity and could be used as improved traditional medicines or, at least, as food additives in
a combined treatment for the control of helminth infections. 相似文献
14.
Passero LF Castro AA Tomokane TY Kato MJ Paulinetti TF Corbett CE Laurenti MD 《Parasitology research》2007,101(3):677-680
The crude methanolic extract from leaves of Jacaranda puberula showed activity against Leishmania (Leishmania) amazonensis. The extract presented active against promastigote forms with an inhibitory concentration 50% (IC50) value of 88.0 μg/ml, but only moderated activity against amastigote forms; however in higher concentrations the extract
showed cytotoxic effects. The bio-guided chromatographic fractionation the crude methanolic extract against amastigotes yielded
a fraction with an IC50 value of 14.0 μg/ml (without cytotoxic activity) in relation to the crude extract (IC50 value, 359.0 μg/ml). These data indicate that J. puberula leaves contain active compounds, which should be further investigated for the development of new potential drugs against
cutaneous leishmaniasis. 相似文献
15.
In this study, we are reporting antileishmanial activity of a marine sponge Haliclona exigua, belonging to phylum Porifera. The crude methanol extract and its three fractions were tested both in vitro and in vivo.
The crude extract exerted almost complete inhibition of promastigotes at 50 μg/ml and 76.4 ± 6.5% inhibition of intracellular
amastigotes at 100 μg/ml concentration with IC50 values of 18.6 μg/ml and 47.2 μg/ml, respectively. When administered to Leishmania donovani infected hamsters at a dose of 500 mg/kg × 5, p.o., it resulted in 72.2 ± 10.4% inhibition of intracellular amastigotes.
At a lower dose (250 mg/kg), it exhibited 43.9 ± 5.1% inhibition. Among the fractions, highest antileishmanial activity both
in vitro (>90%) and in vivo (60.9 ± 18.3%) was observed in n-butanol (soluble) fraction with IC50 values of 8.2 μg/ml and 31.2 μg/ml against promastigotes and intracellular amastigotes, respectively. Hexane fraction also
showed comparatively good activity against both the stages of parasites in vitro but was moderately active in leishmania-infected
hamsters. Chloroform fraction resulted in 45 ± 10.2% inhibition in vivo at a dose of 500 mg/kg × 5, p.o., whereas it was inactive
in vitro. n-Butanol (insoluble) fraction was inactive both in vitro and in vivo. Araguspongin C, an alkaloid isolated from n-butanol (soluble) fraction exhibited moderate inhibition of promastigotes and intracellular amastigotes at 100 μg/ml but
showed weak antileishmanial action in vivo. Our findings indicate that this marine sponge has the potential to provide new
lead toward development of an effective antileishmanial agent and, hence, calls for more exhaustive studies for exploiting
the vast world of marine resources to combat the scourge of several parasitic diseases. 相似文献
16.
Apyrases (ATP diphosphohydrolase) hydrolyze the phosphodiester bonds of nucleoside tri- and diphosphates to orthophosphate
and mononucleodides. They can inhibit platelet activation by depletion of adenosine diphosphate. In the current study, the
Escherichia coli expression vector pET-19b equipped with an N-terminal histidine tag was applied to express the apyrase of Aedes
albopictus. The gene-coding mature apyrase protein was amplified by RT-PCR and cloned into pET-19b. Soluble apyrase protein with high
purity was successfully obtained by utilization of the suitable renaturation approach and Ni-NTA purification column. Four
monoclonal antibodies to apyrase from A. albopictus were produced in male BALB/c mice immunized with the renatured apyrase. Using immunofluorescence assay and immunoblotting
analysis, recombinant apyrase showed fine consistency with native apyrase. From kinetic analysis, it had a K
m of 11.6 μM and V
max of 1.02 nM/S/μg protein for adenosine triphosphate. Adenosine diphosphate-induced platelet aggregation was inhibited by approximately
6% when 0.4 μM recombinant apyrase was added and by about 9.5% when the concentration of recombinant apyrase was 0.8 μM. The
effect on platelet aggregation was dose dependent. In conclusion, the apyrase of A. albopictus was cloned and expressed highly in the E. coli expression system. Recombinant apyrase protein showed biological activity, and anti-apyrase monoclonal antibody was also
prepared. 相似文献
17.
Y. Glupczynski T.-D. Huang C. Berhin G. Claeys M. Delmée L. Ide G. Ieven D. Pierard H. Rodriguez-Villalobos M. Struelens J. Vaneldere 《European journal of clinical microbiology & infectious diseases》2007,26(11):777-783
Temocillin is a narrow spectrum penicillin with high stability to most β-lactamases including AmpC types and extended-spectrum
types (ESBLs). We have analysed its in vitro activity against 652 clinical isolates of Enterobacteriaceae prospectively collected from patients hospitalised in intensive care units at seven different university hospitals in Belgium
in 2005. Strains were screened for ESBL production using cefotaxime and ceftazidime screen agar plates and by double ESBL
E-tests. The MIC of temocillin and of five comparators was determined using the E-test method. ESBLs were characterized at
one central laboratory by isoelectric focusing, PCR for bla genes of the SHV, TEM, and CTX-M families, and by DNA sequencing. The prevalence of ESBL-producing Enterobacteriaceae averaged 11.8% and ranged between 3.0 and 29% in the different hospitals. Meropenem exhibited the highest in vitro activity
overall (mode MIC 0.064 μg; MIC90; 0.19 μg/ml), whereas ceftazidime (MIC90 > 256 μg/ml) and ciprofloxacin (MIC90 > 32 μg/ml) scored the worst. Temocillin was active against more than 90% of the isolates including most AmpC- and ESBL-producing
isolates. These data indicate the well preserved activity of temocillin over the years against Enterobacteriaceae and show the wide variation in prevalence of ESBL-producing Enterobacteriaceae isolates in Belgian intensive care units. Prospective clinical studies are, however, needed to validate the usefulness of
temocillin in the treatment of microbiologically documented infections caused by ESBL- and/or AmpC- overproducing nosocomial
Enterobacteriaceae pathogens. 相似文献
18.
The leishmanicidal activity of Aloe vera leaf exudate (AVL) has been demonstrated in promastigotes and axenic amastigotes, but its effectiveness in animal models
has not been evaluated. The presence of alkaloids, triterpenes, cyanidines, proanthocyanidines, tannins, and saponins in AVL
was identified. Its effectiveness in four Leishmania donovani strains was studied both in promastigotes (IC50 ranged from 70–115 μg/ml) and amastigotes (IC50 ranged from 3.1–11.4 μg/ml). In amastigotes, the killing by AVL was facilitated through its induction of nitric oxide in
leishmania-infected macrophages. The safety index was good as AVL up to 300 μg/ml remained non-toxic to monocytes and macrophages. In
a L. donovani BALB/c mouse model, oral or subcutaneous administration of AVL (15 mg/kg body weight × 5 days) reduced parasitemia by >90%
in the liver, spleen, and bone marrow without impairment of hepatic and renal functions. Collectively, we conclude that AVL
shows promising antileishmanial activity and may provide a new lead agent in the treatment of Leishmaniasis.
Chitra Mandal and Mitali Chatterjee should be considered as joint senior authors. 相似文献
19.
S. B. Tkachenko V. N. Kokryakov I. P. Ashmarin S. V. Grachev A. A. Kubatiev 《Bulletin of experimental biology and medicine》1994,118(6):1291-1294
The effect of the total fraction of human defensins (HNP-1, HNP-2, and HNP-3) on the cytoplasmic Ca2+ content ([Ca2+]i) in the platelets of healthy donors was studied. At concentrations of 0.1–40 μg/ml and an incubation time of 10 min defensins
have no effect on [Ca2+]i in platelets labeled with Fura-2AM. However, at higher concentrations (100 μg/ml) they increased platelet [Ca2+]i. In addition, defensins (40 μg/ml) inhibited the Ca2+ increase in platelets induced by thrombin, adenosine diphosphate, and the lipopolysaccharide ofS. typhimurium endotoxin. The most pronounced inhibitory effect was observed in a suspension of thrombin-stimulated platelets. It is shown
that the effect of human defensins on the functional activity of platelets is due to the alterations in the intracellular
Ca2+.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N
o
12, pp. 600–603, December, 1994 相似文献
20.
Salah F Demerdash Z Shaker Z El Bassiouny A El Attar G Ismail S Badir N El Din AS Mansour M 《Parasitology research》2000,86(1):74-80
A monoclonal antibody (mAb), 2F/11F, raised against Schistosoma haematobium soluble egg antigen (SEA) was found to be nonreactive with S. mansoni SEA or other parasite antigens (Fasciola hepatica, Echinococcus granulosus). This IgG1 mAb recognized a repetitive epitope on S. haematobium SEA in the molecular-weight regions of 70, 42, and 35 kDa. It was employed as both an antigen-capture and a biotinylated
detection antibody in a sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of circulating schistosome antigen
(CSA) and had a detection limit of <1 ng S. haematobium SEA/ml. CSA levels were measured in serum and urine samples from 116 S. haematobium-infected rural students before therapy and at 4, 8, and 12 weeks after praziquantel treatment. Serum and urine samples from
50 S. mansoni -infected patients, 15 patients harboring other parasites, and 30 noninfected individuals were also assessed. CSA was detected
in 90.5% of serum samples and 94% of urine samples from S. haematobium-infected patients. CSA was undetectable in serum from the 15 patients harboring other parasites and in 94% of serum samples
and 84% of urine samples from S. mansoni-infected patients. In the S. haematobium-infected group a positive correlation was detected between CSA levels in serum and urine samples and the egg load per 10 ml
urine. A significant reduction in CSA levels was detected in serum and urine samples after praziquantel therapy. CSA was undetectable
in 87% of serum samples and 81.5% of urine samples from schistosomiasis haematobium patients at 12 weeks post-treatment. These
data demonstrate that the use of mAb 2F/11F for detection of CSA provides a sensitive method for the immunodiagnosis and monitoring
of cure of schistosomiasis haematobium.
Received: 5 December 1998 / Accepted: 26 June 1999 相似文献