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1.
F. Fuentes M. J. Giménez F. Marco L. Alou L. Aguilar J. Prieto 《European journal of clinical microbiology & infectious diseases》2000,19(2):137-139
The in vitro susceptibility to trovafloxacin and gemifloxacin of Streptococcus pneumoniae strains exhibiting decreased susceptibility to ciprofloxacin (MIC ≥2 μg/ml; 30 strains with intermediate resistance [MIC
2 μg/ml] and 43 strains with complete resistance [MIC ≥4 μg/ml]) was determined. Seventy-three strains collected in a surveillance
study carried out from May 1996 to April 1997 in Spain (prior to commercialisation of trovafloxacin and gemifloxacin) from
patients with respiratory tract infections were tested. The antibacterial activity of gemifloxacin was affected to a lesser
extent than that of trovafloxacin by the increase in the MIC of ciprofloxacin, with gemifloxacin showing significantly (P≤0.001) better antibacterial activity than trovafloxacin in all ciprofloxacin MIC categories (MIC50/MIC90 values of 0.015/0.03,
0.015/0.06, 0.03/0.06 and 0.12/0.25 μg/ml for gemifloxacin vs 0.12/0.12, 0.12/1, 0.25/0.5 and 2/4 μg/ml for trovafloxacin
in the 2, 4, 8 and ≥16 μg/ml ciprofloxacin MIC categories, respectively). Nine (12.3%) of these 73 strains exhibited decreased
susceptibility to trovafloxacin (≥2 μg/ml), whereas all strains were inhibited by 0.25 μg/ml of gemifloxacin. 相似文献
2.
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
3.
A simple microfluidic immunoassay card was developed based on polystyrene (PS) substrate for the detection of horse IgG, an
inexpensive model analyte using fluorescence microscope. The primary antibody was captured onto the PS based on covalent bonding
via a self-assembled monolayer (SAM) of thiol to pattern the surface chemistry on a gold-coated PS. The immunosensor chip layers
were fabricated from sheets by CO2 laser ablation. The functionalized PS surfaces after each step were characterized by contact angle measurement, X-ray photoelectron
spectroscopy (XPS), and atomic force microscopy (AFM). After the antibody–antigen interaction as a sandwich immunoassay with
a fluorescein isothiocyanate (FITC)-conjugated secondary antibody, the intensity of fluorescence was measured on-chip to determine
the concentration of the target analyte. The present immunosensor chip showed a linear response range for horse IgG between
1 μg/ml and 80 μg/ml (r = 0.971, n = 3). The detection limit was found to be 0.71 μg/ml. The developed microfluidic system can be extended for various applications
including medical diagnostics, microarray detection and observing protein–protein interactions. 相似文献
4.
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
5.
A. L. Barry P. C. Fuchs S. D. Brown 《European journal of clinical microbiology & infectious diseases》1999,18(4):305-309
Moxifloxacin (Bay 12–8039), ciprofloxacin, and levofloxacin were compared in vitro against 1074 clinical isolates gathered
from different medical centers throughout North America during the winter months of 1997. Moxifloxacin E tests and broth microdilution
tests gave comparable results. Moxifloxacin was particularly potent against respiratory pathogens such as Haemophilus influenzae and Streptococcus pneumoniae. Ciprofloxacin was the most potent study drug against the family of Enterobacteriaceae and Pseudomonas spp. For tests of 5 μg moxifloxacin disks, zone size criteria of ≤17 mm for resistant (MIC ≥8 μg/ml) and ≥21 mm for susceptible
(MIC ≤2 μg/ml) are provisionally proposed for use while clinical trials are under way. 相似文献
6.
G. Abate S. E. Hoffner V. Østergaard Thomsen H. Miörner 《European journal of clinical microbiology & infectious diseases》2001,20(5):329-333
Forty isoniazid-resistant Mycobacterium tuberculosis isolates were characterized on the basis of phenotypic properties (i.e., catalase activity, MIC of isoniazid, and growth
pattern in the presence of 7 different concentrations of isoniazid) and alterations in the katG gene (codons 315 and 463). Three different growth patterns could be distinguished: concentration-dependent inhibition of
growth was observed in 29 strains, similar growth at all concentrations was seen in 7 strains, and enhanced growth at low
concentrations of isoniazid was evident in 4 strains. The MIC of isoniazid was ≤4 μg/ml for 29 of 40 strains. Mutation at
codon 315 of the katG was detected in 28 of 40 strains. However, only one of the seven strains for which the MIC of isoniazid was ≥16 μg/ml had
mutation at this codon. Five of these seven strains for which the MIC was ≥16 μg/ml had no catalase activity. The results
indicate that the MIC of isoniazid for a majority of strains is below the level achievable in serum. Therefore, isoniazid
may be beneficial for the treatment of some cases of multidrug-resistant tuberculosis. Determination of catalase activity
aids in the detection of isolates for which MICs are high and could, in conjunction with molecular methods, provide rapid
detection of most isoniazid-resistant strains. 相似文献
7.
M. M. Lubbe P. L. Botha L. J. Chalkley 《European journal of clinical microbiology & infectious diseases》1999,18(1):46-54
The in vitro activity of 18 antimicrobial agents was determined against 378 anaerobic bacteria isolated in Bloemfontein,
South Africa, during 1996/97. Against the gram-positive isolates, MICs of penicillin and cefoxitin were >0.5 μg/ml and >16 μg/ml,
respectively, for five and three strains of non-perfringens Clostridium spp. Seventeen Peptostreptococcus anaerobius strains were resistant to penicillin (MIC≥2 μg/ml). All gram-positive anaerobes tested except one Peptostreptococcus sp. and one Clostridium sp. were susceptible to dalfopristin-quinupristin (MICs≤1 μg/ml). The carbapenems exhibited excellent activity against the
gram-positive isolates and were effective against most gram-negative anaerobes, with the exception of the fusobacteria. Only
seven strains exhibited decreased susceptibility to trovafloxacin (MICs>2 μg/ml). In mixed anaerobic/aerobic infections, carbapenems
and the fourth-generation quinolone trovafloxacin were the agents most suitable for us as broad-spectrum monotherapy. 相似文献
8.
F. Barchiesi L. Falconi Di Francesco D. Arzeni F. Caselli D. Gallo G. Scalise 《European journal of clinical microbiology & infectious diseases》1999,18(3):184-187
A series of 35 strains of Candida glabrata isolated from 29 subjects (5 AIDS patients and 24 HIV-seronegative individuals) were typed by electrophoretic karyotyping
and tested for their susceptibilities to both fluconazole and itraconazole. Almost every individual harboured his/her own
specific isolate (DNA type). Neither the source of isolation nor the patient's HIV status was associated with a given DNA
type. Recurrences were generally due to the persistence of the same DNA type over time. Only 9% of the isolates showed reduced
susceptibility to fluconazole (MIC≥8.0 μg/ml), while 43% of the isolates showed reduced susceptibility to itraconazole (MIC≥0.25 μg/ml)
(P=0.02). These data show that electrophoretic karyotyping is a useful technique for DNA typing of isolates of Candida glabrata. Care must be taken prior to inititation of antifungal therapy with either of these drugs. 相似文献
9.
Determinants for the Development of Oropharyngeal Colonization or Infection by Fluconazole-Resistant Candida Strains in HIV-Infected Patients 总被引:3,自引:0,他引:3
M. Masiá Canuto F. Gutiérrez Rodero V. Ortiz de la Tabla Ducasse I. Hernández Aguado C. Martín González A. Sánchez Sevillano A. Martín Hidalgo 《European journal of clinical microbiology & infectious diseases》2000,19(8):593-601
A point prevalence study to document oral yeast carriage was undertaken. Risk factors for the development of oropharyngeal
colonization or infection by fluconazole-resistant Candida strains in HIV-infected patients were investigated with a case-control design. Cases included all patients with fluconazole-resistant
strains (MIC≥64 μg/ml), and controls were those with susceptible (MIC≤8 μg/ml) or susceptible-dependent-upon-dose (MIC 16–32 μg/ml)
strains. One hundred sixty-eight Candida strains were isolated from 153 (88%) patients, 28 (16%) of whom had oropharyngeal candidiasis. Overall, 19 (12%) of the patients
harbored at least one resistant organism (MIC≥64 μg/ml). Among patients with resistant strains, tuberculosis (P<0.001), esophageal candidiasis (P=0.001), clinical thrush (P<0.001), and a CD4+ cell count <200/mm3 (P=0.03) were more frequent. These patients had also been treated more commonly with antituberculous drugs (adjusted odds ratio
[OR] 6.13; 95% confidence interval [CI] 2.11–17.80), ciprofloxacin (OR 6.0; 95% CI 1.23–29.26), fluconazole (OR 4.59; 95%
CI 1.55–13.52), and steroids (OR 4.13; 95% CI 1.11–15.39). Multivariate analysis showed that the determinants for fluconazole
resistance were therapy with antituberculous drugs (OR 3.61; 95% CI 1.08–12.07;P=0.03) and one of the following: previous tuberculosis (OR 3.53; 95% CI 1.08–14.57;P=0.03) or fluconazole exposure (OR 3.41; 95% CI 1.10–10.54). Findings from this study indicate that treatment with antituberculous
drugs, previous tuberculosis, and fluconazole exposure are the strongest determinants for development of oropharyngeal colonization
or infection by fluconazole-resistant Candida strains in HIV-infected patients. 相似文献
10.
B. Mikoluc R. Motkowski H. K?yhty E. Heropolitanska-Pliszka B. Pietrucha E. Bernatowska 《European journal of clinical microbiology & infectious diseases》2012,31(5):805-809
Absence of the spleen constitutes a risk of infection caused by encapsulated bacteria. The aim of our study was to determine
the immune response to Haemophilus influenzae type-b (Hib) conjugate vaccine (HibCV) in asplenic individuals, considering the cause of asplenia, the age when splenectomy
was carried out, and previous Hib vaccinations. Twenty asplenic patients, aged five to 25 years, were immunized with a single
dose of HibCV. The specific antibody concentrations against HibCV were measured by enzyme-linked immunosorbent assay. Before
vaccinations, the geometric mean antibody concentration (GMC) had an average value of 3.21 μg/ml and was comparable for all
of the patients, regardless of the causes of asplenia. After vaccinations, the GMC was significantly higher, with an average
of 6.78 μg/ml. Further, 4.5 years after vaccinations, the GMC was comparable to that of previously unvaccinated children.
Moreover, 17/20 patients had GMC ≥ 1.0 μg/ml, which included all of the children with congenital asplenia, children splenectomized
before the age of six years, and only 57% of children splenectomized after that age. HibCV gives asplenic patients long-term
protection. Hence, HibCV should be administered regardless of previous vaccinations and time from splenectomy, even if antibody
evaluation is not available. 相似文献
11.
N. Shime T. Kosaka N. Fujita 《European journal of clinical microbiology & infectious diseases》2010,29(12):1475-1479
The purpose of this investigation was to examine the impact of antimicrobial regimens administered for hospital-acquired methicillin-resistant
Staphylococcus aureus (MRSA) bacteraemia on the all-cause, 14-day mortality. We retrospectively examined the characteristics of the most effective
empiric antimicrobial therapy in 87 consecutive patients, hospitalised at a single institution between April 2003 and March
2008, who presented with clinically and microbiologically confirmed MRSA bacteraemia. The all-cause mortality was measured
14 days after the diagnosis was made. The administration of an effective antimicrobial against MRSA <48 h after the collection
of blood cultures was the single, significant predictor of survival (odds ratio 3.85; 95% confidence interval 1.37–10.80;
p = 0.01). The survival of patients treated with vancomycin versus other antimicrobial agents was similar. Among subgroups
treated with vancomycin, the lowest mortality (6%) was observed among patients treated (a) within 48 h after the collection
of blood cultures and (b) with doses sufficient to keep the blood concentrations in the area under the 0–24 h curve >400 μg
h/ml (≥2.0 g/day). The empiric administration of antimicrobials effective against MRSA bacteraemia within 48 h after the collection
of blood cultures increased the 14-day survival. If vancomycin is chosen, ≥2.0 g/day should be administered, starting within
48 h. 相似文献
12.
Passero LF Tomokane TY Corbett CE Laurenti MD Toyama MH 《Parasitology research》2007,101(5):1365-1371
In this study, we compared the anti-leishmanial activity of three crotalic venoms (Crotalus durissus terrificus–Cdt, Crotalus durissus cascavella–Cdca, and Crotalus durissus collilineatus–Cdcol). Different concentrations of each venom incubated with Leishmania (Leishmania) amazonensis promastigotes were used. Cdt venom exhibited a higher anti-leishmanial activity (Inhibitory concentration-IC50-value of 4.70 ± 1.72 μg/ml) in comparison
with that of Cdca venom (IC50 value of 9.41 ± 1.21 μg/ml), while Cdcol venom increased parasite numbers in 50% at a concentration of 44.30 ± 2.18 μg/ml. In addition, this venom showed a low anti-leishmanial
activity in higher concentrations (IC50 value of 281.00 ± 9.50 μg/ml). The main fractions of Cdca venom were isolated and assayed under similar conditions used for assessing crude venom. The most active fractions were gyroxin
and crotamine that had IC50 values of 3.80 ± 0.52 μg/ml and 19.95 ± 4.21 μg/ml, respectively. Convulxin also inhibited parasite
growth rate, although this effect was not dose-dependent. Crotoxin was the least effective fraction with an IC50 value of
99.80 ± 2.21 μg/ml. None of the protein fractions presented cytotoxic effects against J774 cells in culture. In vivo assays
using BALB/c mice revealed that crotoxin and crotamine were the main toxic fractions. In conclusion, C. durissus cascavella venom has three main fractions with anti-leishmanial activity. These results open new possibilities to find proteins that
might be used as possible agents against cutaneous leishmaniasis. 相似文献
13.
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
14.
M. Cuenca-Estrella T. M. Díaz-Guerra E. Mellado A. Monzón J. L. Rodríguez-Tudela 《European journal of clinical microbiology & infectious diseases》1999,18(6):432-435
The in vitro activity of voriconazole was compared with that of itraconazole against 299 fluconazole-susceptible (MIC≤8 μg/ml)
and 130 fluconazole-resistant (MIC≥16 μg/ml) clinical isolates of Candida spp. An adaptation of the National Committee for Clinical Laboratory Standards reference method was employed for determination
of MICs. Voriconazole showed more potent activity than either fluconazole and itraconazole, even against some Candida
albicans, Candida
glabrata, and Candida
krusei isolates resistant to fluconazole. However, for fluconazole-resistant isolates, the MICs of itraconazole and voriconazole
were proportionally higher than for fluconazole-susceptible isolates. These data may indicate cross-resistance. 相似文献
15.
Marise M. O. Cabral Patrícia Azambuja Otto R. Gottlieb Eloi S. Garcia 《Parasitology research》1999,85(3):184-187
Two neolignans, burchellin and nordihydroguaiaretic acid (NDGA), were toxic only to Trypanosoma cruzi clone Dm28c maintained in brain heart infusion (BHI) medium at a concentration of 100 μg/ml, not 10 μg/ml. When Rhodnius prolixus was fed with epimastigotes of T. cruzi and treated simultaneously with a single dose of burchellin or NDGA at 10 μg/ml of blood meal the number of parasites in
the gut decreased. Whereas burchellin was only partially active, NDGA drastically reduced the number of epimastigotes and
metacyclic trypomastigotes of T. cruzi in the excreta (urine plus feces). When the insect larvae were pretreated with burchellin or NDGA at 20 days before the infection
with T. cruzi a significant reduction in the number of parasites in the gut occurred. However, when both compounds were applied at 20 days
after the establishment of T. cruzi infection, although burchellin significantly reduced the gut infection, neither compound could abolish the infection entirely
within the subsequent 15 days.
Received: 15 June 1998 / Accepted: 15 August 1998 相似文献
16.
Experiments on Wistar rats showed that exenatide (0.015–0.5 nmol per 100 g body weight) somewhat increased renal excretion
of potassium from 7 ± 1 to 16 ± 1 μmol/h/100 g body weight (p < 0.05) in animals with normal serum concentration of glucose (4.6 ± 0.4 mM) and potassium (4.3 ± 0.1 mM). Exenatide dramatically
enhanced excretion of potassium under conditions of hyperkalemia (11.4 ± 0.4 mM) produced by intraperitoneal injection of
1.25% KCl solution (5 ml per 100 g body weight). During the fi rst postinjection hour, potassium excretion increased 2-fold
and attained 97 ± 11 μmol/h/100 g body weight in comparison with potassium load alone (47 ± 9 μmol/h/100 g body weight, p < 0.05). The data attest to a possible role of peptide regulators in normalization of potassium balance via renal mechanisms. 相似文献
17.
R. M. Anthony A. M. Connor E. G. M. Power G. L. French 《European journal of clinical microbiology & infectious diseases》1999,18(1):30-34
The minimum inhibitory concentrations (MICs) of mupirocin were determined by the E test (AB Biodisk, Sweden) and the agar
dilution method for 107 staphylococci. The organisms consisted of 34 coagulase-negative staphylococci and 73 methicillin-resistant
Staphylococcus aureus. Polymerase chain reaction (PCR) primers designed to amplify a 456 bp region of the plasmid-borne isoleucyl tRNA synthetase
gene (ileS–2), responsible for high-level mupirocin resistance in staphylococci, were used on DNA preparations from these isolates.
Isolates with high-level mupirocin resistance due to the ileS–2 gene should be PCR positive. There was close correlation between the E test and agar dilution MIC values, with only two
strains differing by more than two serial dilutions. Most (51 of 54 strains) of the high-level resistant strains (MIC>256 μg/ml)
were resistant to the highest concentration of mupirocin tested (1024 μg/ml). PCR correctly classified all but four (96%)
of the isolates in accordance with the results of agar dilution. All four isolates that gave discrepant results were methicillin-resistant
Staphylococcus aureus. Two of these were PCR positive, yet the MIC of mupirocin for these strains was <0.06 μg/ml; on prolonged incubation they
produced halos within the inhibition zone on agar diffusion testing, suggesting that the phenotypic results may have been
erroneous. One of 54 isolates for which the MIC exceeded 256 μg/ml was PCR negative when tested by the original methodology,
but a 456 bp product was produced when retested using a lowered annealing temperature. One isolate for which the MIC of mupirocin
was 16 μg/ml by agar dilution and 8 μg/ml by the E test was positive by PCR. PCR of the ileS–2 gene is a useful, rapid method for detecting high-level mupirocin resistance in staphylococci. 相似文献
18.
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
19.
Misra S Verma M Mishra SK Srivastava S Lakshmi V Misra-Bhattacharya S 《Parasitology research》2011,109(5):1351-1360
The present study is aimed to evaluate antifilarial activity of Xylocarpus granatum (fruit from Andaman) against human lymphatic filarial parasite Brugia malayi in vivo. The in vitro antifilarial activity has already been reported earlier for this mangrove plant which has traditionally
been used against several ailments. Aqueous ethanolic crude extract, four fractions (ethyl acetate fraction, n-butanol fraction, water-soluble fraction and water-insoluble fraction) and pure molecule/s of X. granatum (fruit) were tested in vitro on adult worms and microfilariae (mf) of B. malayi and the active samples were further evaluated in vivo in B. malayi (intraperitoneally) i.p. transplanted in the jird model (Meriones unguiculatus) and Mastomys coucha subcutaneously infected with infective larvae (L3). The crude aqueous ethanolic extract was active in vitro (IC50: adult = 15.46 μg/ml;
mf = 13.17 μg/ml) and demonstrated 52.8% and 62.7% adulticidal and embryostatic effect on B. malayi, respectively, in Mastomys at a dose of 5 × 50 mg/kg by oral route. The antifilarial activity was primarily localized in the ethyl acetate-soluble fraction
which revealed IC50 of 8.5 and 6.9 μg/ml in adult and mf, respectively. This fraction possessed moderate adulticidal and embryostatic
action in vivo in Mastomys. Out of eight pure molecules isolated from the active fraction, two compounds gedunin (IC50 = 0.239 μg/ml, CC50 = 212.5 μg/ml,
SI = 889.1) and photogedunin (IC50 = 0.213 μg/ml, CC50 = 262.3 μg/ml, SI = 1231.4) at 5 × 100 mg/kg by subcutaneous route
revealed excellent adulticidal efficacy resulting in to the death of 80% and 70% transplanted adult B. malayi in the peritoneal cavity of jirds respectively in addition to noticeable microfilaricidalo action on the day of autopsy.
The findings reveal that the extract from the fruit X. granatum contains promising in vitro and in vivo antifilarial activity against human lymphatic filarial parasite B. malayi which could be attributed to the presence of two pure compounds gedunin and photogedunin. 相似文献
20.
S. T. Yildiran M. A. Saracli A. W. Fothergill M. G. Rinaldi 《European journal of clinical microbiology & infectious diseases》2000,19(4):317-319
The in vitro antifungal susceptibility of 27 environmental (pigeon droppings) isolates of Cryptococcus neoformans var. neoformans, isolated from throughout Turkey, to six antifungal agents (amphotericin B, flucytosine, fluconazole, voriconazole, itraconazole,
and SCH56592) was studied. Voriconazole, itraconazole, and SCH56592 all showed comparable activity and were more active than
the remaining three antifungal agents tested. Overall, SCH56592 was the most active agent (MIC90, 0.015 μg/ml, at both 48
and 72 h), followed by itraconazole (MIC90, 0.03 μg/ml, at both 48 and 72 h) and voriconazole (MIC90, 0.25 μg/ml, at both
48 and 72 h), respectively. Antifungal susceptibility data for environmental isolates may reflect patterns for the clinical
isolates recovered from patients from the same geographic area. 相似文献