Insights into the Novel Cardiac Biomarker in Acute Heart Failure: Mybp-C

(1) Background: Given its high cardiac specificity and its capacity to directly assess the cardiac function, cardiac myosin-binding protein (MyBP-C) is a promising biomarker in patients with acute heart failure (AHF). The aim of our study was to investigate the clinical utility of this novel marker for diagnosis and short-term prognosis in subjects with AHF. (2) Methods: We measured plasma levels of MyBP-C at admission in 49 subjects (27 patients admitted with AHF and 22 controls). (3) Results: The plasma concentration of MyBP-C was significantly higher in patients with AHF compared to controls (54.88 vs. 0.01 ng/L, p < 0.001). For 30-day prognosis, MyBP-C showed significantly greater AUC (0.972, p < 0.001) than NT-proBNP (0.849, p = 0.001) and hs-TnI (0.714, p = 0.047). In a multivariate logistic regression analysis, an elevated level of MyBP-C was the best independent predictor of 30-day mortality (OR = 1.08, p = 0.039) or combined death/recurrent 30-days rehospitalization (OR = 1.12, p = 0.014). (4) Conclusions: Our data show that circulating MyBP-C is a sensitive and cardiac-specific biomarker with potential utility for the accurate diagnosis and prognosis of AHF.

Antioxidant and antimicrobial effects of grape pomace extracts

The use of antioxidants and antibacterials in food industry has become increasingly necessary to ensure the high quality of food. Grape pomace is the main by-product of winemaking industry that concentrates bioactive metabolites with more studied antioxidant activity and possible antibacterial activity. The grape pomace contains fragmented skin, broken cells, pulp remains, stalks and seeds with high amount of phenolic compounds due to their poor extraction during the winemaking process. Anthocyanins, catechins, flavonol glycosides, phenolic acids, alcohols and stilbenes have been identified among the compounds present in grape pomace. In this study, antibacterial activity against different pathogens (Escherichia coli ATCC 25922, Candida albicansATCC 90028, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 25923) was evaluated and the relation with polyphenols content and antioxidant activity of grape pomace from selected grapes from Iaşi vineyard was studied. The grape pomace samples were obtained after the fermentation process from the 2017 harvest of Sauvignon Blanc, Traminer, Busuioacă de Bohotin, Cabernet Sauvignon, Merlot, Fetească Neagră and Fetească Regală grape varieties. The antioxidant properties were evaluated using the DPPH method, FRAP assay and Folin Ciocalteu method. The content of resveratrol was quantified using an HPLC method. Samples with antioxidant activity showed the highest phenolics content. This study reveals that grape pomace is a potential source of natural antioxidant agents. The pomace extracts were tested to establish the effects on Gram-positive and Gram-negative bacteria. The analysed samples exhibited insignificant antibacterial activity and the method requires optimization. Grape marc represents an important source of resveratrol and other bioactive compounds that could be a valuable source of antioxidants for further utilization in food and pharmaceutical industry.

LOW LEVELS OF SERUM CYANOCOBALAMIN IN A METFORMIN-TREATED PATIENT. CASE REPORT AND COMPARISON WITH LITERATURE DATA

Metformin is a widely used oral antidiabetic biguanide compound. According to the literature, metformin may lower the serum cyanocobalamin levels. We present the case of a 71-old-male treated with metformin for 15 years. When presenting to a periodic checkup, low serum cyanocobalamin levels where found. Laboratory tests showed levels below normal range for hemoglobin (12.7 g/dL) and hematocrit (37.8%). After patient reevaluation, a change in antidiabetic treatment will be considered if metformin will be found the cause of low serum cyanocobalamin levels. Other cases reported in the literature support this hypothesis, justifying the study of the influence of metformin therapy on serum vitamin B12 levels in patients diagnosed with diabetes. The influence of patient age, metformin dosage, duration of treatment and time since diabetes diagnosis on serum levels of vitamin B12 also need to be determined.

α,β-DIBROMOCHALCONE DERIVATIVES--SYNTHESIS AND ANTIMICROBIAL ACTIVITY

AIM

To obtain some chalcones and their dibrominated analogues and to evaluate their antimicrobial potential.

MATERIAL AND METHODS

Eight chalcones were synthesized using the Claisen-Schmidt condensation of acetophenone/4-bromo-acetophenone and different benzaldehyde derivatives. These chalcones were further brominated using two different bromination agents: molecular bromine and pyridinium tribromide. The antimicrobial activity was tested using the disk diffusion method.

RESULTS AND DISCUSSIONS

The classical bromination technique was compared to the eco-friendly one using pyridinium tribromide. Pyridinium tribromide bromination did not improve the reaction yields (except for one compound), but it had the advantage of being a stable, non-corrosive and non-toxic salt. The results of the antimicrobial assessment indicated that the bromination of the double bond slightly increased the antimicrobial potential in some cases, but the results obtained during the antimicrobial evaluation were modest, some of the derivatives being active especially on Sarcina lutea ATCC 9341 and Bacillus cereus ATCC 14579.

CONCLUSIONS

In this study, eight chalcones and their dibrominated analogues were synthesized, four of the α,β-dibromochalcones being reported for the first time. Pyridinium tribromide was used as an alternative for liquid bromine, the main advantage of this method being related to the reduced toxicity of the reagents. The synthesized compounds did not exhibit a very good antimicrobial potential.

Assessment of the microbial load of some medicinal plants commonly used in Romania

AIM

This study aims to assess the microbial load of some medicinal plants (Matricaria chamomilla, Achillea millefolium, Ocimum basilicum, Calendula officinalis, Tilia cordata, Hypericum perforatum) commonly used as medicinal teas.

MATERIAL AND METHODS

A total of 24 samples collected from the local market, as well as from the spontaneous flora of Galati County, were analyzed in terms of the total number of germs, the content of coliform bacteria, yeasts and molds, and the presence of specific pathogenic bacteria (Escherichia coli, Bacillus cereus, Coagulase-positive Staphylococcus, Salmonella spp.).

RESULTS

The values obtained for total number of germs, yeasts and molds were in accordance with the limits set by the European Pharmacopoeia for plant products to which hot water is added before use. In the case of specific pathogenic bacteria, the presence of E. coli was confirmed in 41.66% of the samples, the presence of Coagulase-positive Staphylococcus in 16.66% of the samples, and the presence of Bacillus cereus in 33.33% of the samples. Salmonella spp. was absent in all samples.

CONCLUSIONS

The study highlights a certain microbial load of medicinal plants analyzed, emphasizing the importance of quality control in all stages of production.

Echinocandins--new antifungal agents

Over the past 10-15 years, the number of clinically available antifungal agents has increased substantially, due to rise in the number of invasive fungal infections, which are a real problem for specialists. Echinocandins are the new class of antifungal agents available for clinical use. This class comprises over 20 natural echinocandins and several semisynthetic ones. Natural echinocandins are not of clinical utility due to their toxicity and low water-solubility (which does not allow obtaining parenteral pharmaceutical forms), although they have good antifungal activity against Candida species. Consequently, semisynthetic echinocandins with minimal toxicity, good antifungal activity and high water-solubility were obtained. All echinocandins inhibit beta-1,3-glucan-synthase, an essential component of the fungal cell wall. Echinocandins exhibit potent antifungal activity against key pathogenic fungi, including Candida species, Aspergillus species and Pneumocystis carinii. The available echinocandins lack in vitro activity against Cryptococcus neoformans. The semisynthetic echinocandins have great advantages, among which low toxicity, fast antifungal activity, favorable pharmacokinetics that allow once-daily administration. The echinocandins recently available for clinical use are: caspofungin, micafungin and anidulafungin.

New hydrazones with pyrazolone structure: synthesis, characterization and biological evaluation

AIM

To design new hydrazones with pyrazolone structure with improved biological properties.

MATERIAL AND METHODS

New hydrazones of antipyrine have been prepared by reaction of 4-aminophenazone (4-aminoantipyrine) with chloracetylchoride and hydrazine hydrate and then condensation with various aromatic aldehydes.

RESULTS

The synthesized compounds were screened for their antibacterial activity against Gram positive (Staphylococcus aureus ATCC 25923, Sarcinalutea ATCC 9341, Bacillus cereus ATCC 14579, Bacillus subtilis) and Gram negative bacterial strains (Escherichia coli ATCC 25922) and pathogenic yeasts (Candida albicans ATCC 10231, Candida sake, Candidaglabrata). Some of them were found to have good antibacterial and antifungal activity. The antioxidant activity of these compounds was also evaluated using the total antioxidant capacity test.

CONCLUSIONS

The chemical modulations performed on antipyrine structure have a good influence on the biological activity of the synthesized compounds.

New derivatives of aryl-propionic acid. Synthesis and biological evaluation

AIM

To design new derivatives of aryl-propionic acid with potential antibacterial and antioxidant activity.

MATERIAL AND METHODS

New hydrazone of ibuprofen (2-(4-isobutylphenyl)propionic acid) have been synthesized by reaction of ethyl ester of ibuprofen with hydrazine hydrate and then condensation of corresponding hydrazide with various aromatic aldehydes.

RESULTS

The synthesized compounds were screened for their antibacterial activity against Gram positive (Staphylococcus aureus ATCC 25923, Sarcinalutea ATCC 9341, Bacillus cereus ATCC 14579, Bacillus subtilis) and Gram negative bacterial strains (Escherichia coli ATCC 25922). Some of them were found to have good antibacterial activity. The antioxidant activity of these compounds was also tested using the total antiox idant capacity test.

CONCLUSIONS

The chemical modulations performed on ibuprofen structure have a good influence on the biological activity of the synthesized compounds.

[Antimicrobial activity of some cinnamic acid derivatives]

Due to drug-resistance phenomenon, there is a constant need for discovering new antiinfectious agents. A series of cinnamic acid derivatives was synthesized and then brominated with bromine in the presence of chloroform or acetic acid. The structure of the new compounds was confirmed by elemental and spectral data. Their antimicrobial activity was tested by disc-diffusion method. The tested compounds had mainly antifungal activity and were moderately active against Gram-positive bacteria. Bromination of the double bond determined the enhancement of the antimicrobial activity for all the tested compounds.

[Research regarding extended-spectrum beta-lactamases produced by enterobacteria strains]

AIM

To evaluate the susceptiblity of extended spectrum beta-lactamase (ESBL) producing organisms among Escherichia coli and Klebsiella pneumoniae, isolated between January-October 2009 from hospital and community.

MATERIALS AND METHODS

From 611 enterobacteria strains, for 112 strains (E. coli, n = 84 and K. pneumoniae, n = 28), the ESBL phenotypic confirmation was performed with double disk test (DDT) and the replacement disk method. The minimum inhibitory concentrations (MICs) for next antimicrobial agents tested: ceftazidime, cefotaxime, ceftriaxone, cefepime, cefpirome, imipenem, meropenem, ertapenem, moxifloxacin, gatifloxacin, levofloxacin, ofloxacin were performed by agar dilution method. Resistance rates were reported using the Clinical Laboratory Standard Institute (CLSI) breakpoints for the fully susceptible category; moderately susceptible isolates were classified as resistant. K. pneumoniae ATCC 700603 and E. coli ATCC 25922 were used for quality control.

RESULTS

Resistance rates for ceftazidime, cefotaxime, ceftriaxone and aztreonam among tested strains were very high: 84.5%, 100%, 100% and 96.4% for E. coli and 98.8%, 98.8%, 97.6% and 89.2% for K. pneumoniae, with the MIC90 values > 256 mg/L for either antimicrobial tested agent. The MICs for fourth generation cephalosporins ranges from 4 mg/L to 512 mg/L. The MICs for tested quinolones were > 2 mg/L for 89.2% strains. Using breakpoint for susceptibility, all isolates were sensitive to ertapenem, imipenem and meropenem.

CONCLUSIONS

We noticed a high resistance rate for ceftazidime, cefotaxime, ceftriaxone and aztreonam. In this study, carbapenems demonstrated the highest degree of activity.

[Chromogenic medium for detection of enterobacteria producing beta-lactamases in North-Eastern Romania]

We evaluated the performances and analyzed practicability of an ESBL-detecting chromogenic agar medium (chromID ESBL, bioMerieux) for the screening of ESBL production.

MATERIAL AND METHODS

We have tested 112 enterobacteria strains, isolated in 2009 year, in North Eastern region of Romania. Each bacterial strain was cultured on a prepared plate chromogenic medium and the results were recorded after incubation at 37 degrees C for 18 to 24 h or, if necessary, for 48 h. We calculated the sensitivities, specificities, and positive and negative predictive values for this medium, using as gold standard ceftzidime or cefotaxime and clavulanate combination disks on Iso-Sensitest agar. K. pneumoniae ATCC 700603 and E. coli ATCC 25922 were used as the positive and negative control for ESBL production, respectively.

RESULTS

For all tested strains, the chromID ESBL agar showed a high sensitivity (97%), but a low specificity (66%). The positive and negative predictive values were 98% and 57%, respectively. The chromID ESBL had false-positive results for 2 confirmed ESBL-positive strains.

CONCLUSION

The very good sensitivity of the chromID ESBL agar ESBL detection represent a convenient method for the recovery and identification of ESBL-producing enterobacteria.

Antibacterial activity of some Artemisia species extract

The antimicrobial activities of ethanol, methanol and hexane extracts from Artemisia absinthium, Artemisia annua and Artemisia vulgaris were studied. Plant extracts were tested against five Gram-positive bacteria, two Gram-negative bacteria and one fungal strain. The results indicated that Artemisia annua alcoholic extracts are more effective against tested microorganisms. However, all plants extracts have moderate or no activity against Gram-negative bacteria. The obtained results confirm the justification of extracts of Artemisia species use in traditional medicine as treatment for microbial infections.

[Microbiological evaluation of some commercial brands of Chamomillae floss]

Different strains of microorganisms contaminate medicinal herb, and theirs, enzymes could modify the normal composition of herbal products.

MATERIAL AND METHODS

We evaluated the microbiological quality of 12 samples of Chamomillae floss commercialized in, markets and specific stores. Microbiological quality has been evaluated according European Pharmacopoeia rules. In all samples we determined the total number of germs, total number of fungi and we evaluated the presence of coliform bacilli, respectively Staphylococcus species.

RESULTS

For all samples, the total number of germs was under the limits with variation between 320 CFU/g (P 4) and 14000 CFU/g (P 11). The total number of fungi was under the limits; in most of samples, we detected Penicillium sp. and Aspergillus sp. In 4 samples the total number of Escherichia coli strains was over the limits (100 CFU/g).

CONCLUSIONS

An important decrease of total number of coliform bacilli was observed after boiling water has been added but the total number of germs was decreased insignificantly, so these extracts are not very safe for patient especially when vegetal products contain a great number of germs.

[In vitro susceptibility of staphylococci to ciprofloxacin]

OBJECTIVE

To evaluate the in vitro activity of ciprofloxacin against communitary and hospital staphylococcal strains isolated during 2006-2008 in Eastern region of Romania.

MATERIAL AND METHODS

We have tested 1022 staphylococci strains, identified by conventional laboratory methods. Minimum inhibitory concentrations (MICs) were determined by agar dilution method, according to NCCLS.

RESULTS

For both hospital and communitary isolates, MIC 90 was 0.25 mg/L (4 fold less than breakpoint for sensitivity). Resistance was absent or reduced (1.7%) for coagulase- positive staphylococci, both communitary and hospital. For coagulase negative staphylococci, resistance for clinical strains is increased (6%) compared to comunitary strains (0.3%). In conclusion, ciprofloxacin is highly effective against staphylococci representing a therapeutic option for multiresistant strains. Our data shown the necessity of adequate antibiotic use in the hospital and community.

In vitro antimicrobial activity and chemical composition of the essential oil of Foeniculum vulgare Mill

In our study, four samples of volatile oil from Foeniculum vulgare, cultivated in different pedoclimatic conditions, were investigated for their antimicrobial activity and chemical composition.

MATERIAL AND METHODS

Organisms. Staphylococcus aureus ATCC 25923, Bacillus cereus, Pseudomonas aeruginosa, Escherichia coli ATCC 25922, Candida albicans were included in the report. Antimicrobial susceptibility tests. The comparative inhibitory activity of volatile oil samples with other antimicrobial agents was quantitative determined by minimum inhibitory concentration (MIC). Oil samples are the volatile oils extracted by steam distillation, from two ecological vegetative populations of Foeniculum vulgare. Gas chromatography coupled to mass spectrometry (GC-MS) was used to determine the chemical composition of the essential oils.

RESULTS

All oil samples have a good activity against E. coli and S. aureus at low concentrations. Against B. cereus and P. aeruginosa these oil samples are less active. The oil samples were generally bactericidal at a concentration up to twofold or fourfold higher than the MIC value. Significantly synergic activity with amoxicillin or tetracycline showed all fennel samples against E. coli, Sarcina lutea and B. subtilis strains. Fennel oil samples have shown high activity against Candida albicans.

CONCLUSION

No significant antimicrobial activity variations were observed for Foeniculum vulgare volatile oil samples obtained after two or three years cultivation period. The most important identified compounds in all samples of fennel volatile oils were trans-anethole, estragole, fenchone, limonene, alpha-pinene and gamma-terpinene.

Chemical composition and in vitro antimicrobial activity of essential oil of Melissa officinalis L. from Romania

Melissa officinalis L. (lemon balm) is used in traditional medicine to treat insomnia, anxiety, gastric conditions, psychiatric conditions, migraines, hypertension and bronchial conditions. Natural essential oils (mixtures of fragrant chemical) obtained from various parts of plants are efficient active antimicrobial agents. The widespread use of antimicrobial agents selects resistant bacterial strains, which seriously compromise the effectiveness of antibiotic treatment. The use of herbal medicines might be a precautionary measure to prevent the development of lack of susceptibility to synthetic antibiotics that is associated with therapeutic failures.

MATERIAL AND METHODS

In this work, the chemical composition and the antimicrobial properties of essential oil from romanian Melissa officinalis were determined. Therefore, the purpose of this study was to evaluate in vitro antimicrobial activity of lemon balm oil by comparison with lavender essential oil, which is also utilised for its antimicrobial properties in folk medicine.

RESULTS

The most important identified compounds, well known for their antimicrobial effects were citral (neral and geranial) (16.10%), citronellal (3.76%) and trans-caryophyllene (3.57%).The lemon balm oil sample exhibited a higher degree antibacterial activity than did Lavandula oil against Gram-positive strains. The both oil samples tested has shown a high activity against Candida albicans. The gram-negative bacteria were not affected by the lemon balm oil.

[Research concerning rutin semisynthetic derivatives. Synthesis, physico-chemical and microbiological characterisation of some new rutin-isoniazid derivatives]

Isoniazid is one of the most used antituberculosis drugs, but its toxicity is high. In this study, four derivatives of rutin and isoniazid were prepared and their antibacterial and antimycotic activities were investigated.

METHOD

Synthesis of these compounds started through reaction of rutin with fresh prepared sodium methoxide, subsequently treating with 1, 3-dichloro-2-propanol, 1-brom-3-chloropropane, 1, 2-dibrom-ethane or dibrommethane and finally, stirring with isoniazid, to afford crystalline, yellow, water soluble powders.

RESULTS

The four compounds were marginally active against Staphylococcus aureus and Staphylococcus saprophyticus and were inactive against Escherichia coli.

CONCLUSION

We synthesised four new derivatives of rutin and isoniazid; melting points, solubility, yields characterised these compounds, and their structure was confirmed by C, H, N elemental analysis and UV spectra. The compounds showed a modest antibacterial activity. We think that the toxicity of the new derivatives will be lower that of isoniazid toxicity. The next steps in our research will be the toxicological study and antituberculosis assay.

[In vitro activity of ertapenem against staphylococci]

Ertapenem is a new carbapenem with an excellent activity against different Gram-negative and Gram-positive bacteria. Its good antibacterial activity is closely related to high hydrolysis resistance by bacterial beta-lactamases.

MATERIAL AND METHOD

We evaluated antimicrobial activity of ertapenem by comparison that of methicillin, gatifloxacin, cefepime and linezolid against 455 staphylococci collected during 2006-2007 period from healthy individuals.

RESULTS

Minimum inhibitory concentrations were determined by agar dilution technique. Ertapenem has an activity comparable to the other tested agents. Resistance rate was 1% for all investigated strains.

In vitro study of staphylococci susceptibility to gatifloxacin

Gatifloxacin is in a class of drug called fluoroquinolone antibiotics. It eliminates bacteria that cause many infections, such as pneumonia and bronchitis, sinus, respiratory tract and urinary tract infections and sexually transmitted diseases. Gatifloxacin ophthalmic solution is used to treat bacterial conjunctivitis.

AIM

The purpose of this study was to evaluate the in vitro activity of gatifloxacin against recent 457 staphylococci, community isolates and compared it with that of pefloxacin.

MATERIAL AND METHOD

Powders of gatifloxacin and pefloxacin, obtained from commercial sources were tested in concentration range from 0.125 to 64 mg/l. Minimum inhibitory concentrations (MICs) were determined by the agar dilution method established by NCCLS guidelines.

RESULTS

The MIC 50 values for tested quinolones against coagulase-positive staphylococci are identically with MIC 90 (0.125 mg/l for gatifloxacin and 0.25 mg/l for pefloxacin respectively). Against coagulase-negative staphylococci the MICs 50 values were two-fold smaller than MICs 90 values for both gatifloxacin and pefloxacin.

CONCLUSIONS

Gatifloxacin was more active than pefloxacin against coagulase-positive and coagulase-negative staphylococci.

Cefpirome susceptibility in staphylococci isolates

Cefpirome is a fourth-generation cephalosporin with an expanded spectrum against both Gram-negative and Gram-positive bacteria. The objective of this study was to evaluate the in vitro activity of cefpirome against staphylococci, clinical isolates. For comparison oxacillin was also tested.

MATERIAL AND METHODS

A total 434 isolates (coagulase-positive staphylococci, n = 268 and coagulase-negative staphylococci, n = 166) were tested. Susceptibility testing was performed using the Mueller-Hinton agar dilution method.

RESULTS

Cefpirome inhibited the majority of strains at 0.5-8 mg/l. Cefpirome had excellent activity against coagulase-negative staphylococci with 91.6% susceptibility. Except the coagulase-positive staphylococci, of the 268 isolates, 81.3% were cefpirome sensitive. Concerning oxacillin, 35.1% of coagulase-positive staphylococci isolates were resistant, comparative with 26.5% of the coagulase-negative staphylococci. A cross-resistance analysis showed the association of resistance between cefpirome and oxacillin.

CONCLUSION

Against staphylococci, cefpirome had the best activity when compared with the oxacillin.

Correlation between linezolid zone diameter and minimum inhibitory concentration values determined by regression analysis

Linezolid is a new synthetic antibiotic belonging to the oxazolidinone class, available for the therapy of gram-positive infections, caused by methicillin-resistant staphylococci, vancomycin-resistant enterococci and penicillin-resistant pneumococci. The aim of the study was to determine the in vitro activity of linezolid against staphylococci strains and also to determine the relationship between the minimum inhibitory concentration (MIC) and inhibition zone diameter by calculating the regression analysis. We tested one hundred S. aureus isolates, obtained from healthy persons (naso-pharyngeal swabs) during 2005 year. The antibiotic susceptibility of strains was determined by disk diffusion standardized method and by agar dilution method using a multipoint inoculator. The relationship between the diameter of the inhibition zone produced by a linezolid disc impregnated with a fixed amount (30 eg) was determined by regression performed with the least squares method, considering the log2 of the minimum inhibitory concentrations (MICs) as the independent variable and the zone diameter as the dependent variable. The MIC values expressed in logarithmic form are plotted against inhibition zone diameter (arithmetic scale) of the same strain. The activity of linezolid against staphylococci was very good, with MIC 90 of 1 mg/l. All strains were fully sensitive. The regression line for linezolid passes through a continuous series of points that all are approximately located on the a straight line. For each of the MIC values the differences result no greater than 23 mm in diameter sizes were registered. Regression equation was y= -0.188x + 8.048. In conclusion, the regression line analysis calculated for linezolid, demonstrates a significant correlation between MIC values and the inhibition zone diameters obtained by a 30 mg disc.

Antimicrobial susceptibility of Staphylococcus aureus isolated from colonized hospital personnel

The present study was performed to investigate the in vitro activity of oxacillin and other antimicrobial agents against S. aureus strains obtained from nursing personnel. We tested 127 S. aureus colonizing nasal mucous and hand skin and isolated from nursing personnel of University Hospital Department of Infectious Diseases, Iaşi, during June 2005 period. Minimum inhibitory concentrations (MICs) were determined by the dilution method in Mueller-Hinton agar. Most of the S. aureus strains were susceptible to tested agents excepted erythromycin and azithromycin. Erythromycin and azithromycin resistance was observed among 29.1% respectively 22% of S. aureus strains. Vancomycin was active against all isolates. Teicoplanin was active against against all MRSA excepted one of the strain, with an reduced susceptibility. Linezolid has very good in vitro activity against staphylococci, with an MIC 90 of 2 mcg/ml and only 0.8% resistance. The MIC values range was between 0.5-2 mcg/ml. In conclusion, the usually hygienic methods (disposable gowns, hygienic hand disinfection after each patients contact, masks use when is a risk of aerosolization of MRSA) are indicate for significantly reducing of these strains.

Susceptibility of Klebsiella spp. to cefpirome and cefepime

Cefpirome and cefepime possess a greater antibacterial spectrum in vitro than third-generation cephalosporins because they are active against Enterobacteriaceae, which produce beta-lactamases, which may inactivate third-generation cephalosporins. The aim of this study was to quantitatively compare the in vitro activity of cefpirome and cefepime against Klebsiella spp. isolates. We have studied 342 Klebsiella spp. clinical isolates, from some hospitals in Eastern Romania. Minimum inhibitory concentrations (MICs) were determined by the dilution method in Mueller-Hinton agar. The mean MIC of sensitive population by cefpirome and cefepime was 1 mg/l, eight fold lower than breakpoint for susceptibility. The cefpirome and cefepime MICs remained below the proposed breakpoints for sensitivity of 8 mg/l for more 60% of strains. Mean "S" (mean MIC of the fully sensitive strains) is a very good indicator of the drug activity. Cefpirome and cefepime are active fourth-generation cephalosporins against clinical isolates of Klebsiella spp.

[Susceptibility to norfloxacin of some bacterial strains causing urinary infections]

The purpose of this study was to evaluate the in vitro activity of norfloxacin in comparison with ofloxacin, pefloxacin and ciprofloxacin against 662 strains. The studied strains were obtained from urine, during 2003 period, in Eastern region of Romania. The minimum inhibitory concentrations (MICs) were determined on Mueller-Hinton agar by the dilution technique, with an inoculum of 10(5) CFU/spot. Among tested quinolones, norfloxacin has the better activity against tested strains. The fluoroquinolone compounds were very potent against Escherichia coil strains. Our data shown the spread of quinolone resistance in our area and demonstrated the necessity of adequate antibiotic use in the hospital and community.

[Screening methods for detection of metallo-beta-lactamase producing gram negative rods]

Modified Hodge test and a method using a disk with imipenem plus 1000 mg of EDTA were used to determine the presence of metallo-beta-lactamase producing gram-negative rods among 166 clinical isolates from hospitals in Iaşi and Galaţi. Of 9 imipenem resistant strains found, only one Pseudomonas aeruginosa gave positive results with both tests and other two P. aeruginosa clinical isolates gave negative results with both tests. The rest of the strains (2 P. aeruginosa, 2 Acinetobacter baumanii, 1 Sphingomonas paucimobilis) did not give conclusive results. These screening methods are useful, simple and accessible to clinical laboratories. PCR is needed to confirm the presence of metallo-beta-lactamase gene in bacteria and to determine the type of the enzymes.

[Meropenem activity against staphylococci]

Meropenem is a new carbapenem with excellent activity against different Gram-negative and Gram-positive bacteria. Its good antibacterial activity is closely related to high hydrolysis resistance by bacterial beta-lactamases. The aim of this study was to evaluate antimicrobial activity of meropenem by comparison that of oxacillin, gentamicin, clarithromycin and ciprofloxacin against 458 staphylococci collected during 2004 period from healthy individuals. Minimum inhibitory concentrations were determined by agar dilution technique. Meropenem has an activity clearly superior to the other tested agents. Resistance rate is zero for all investigated strains.

[In vitro susceptibility of a Staphylococcus spp. isolate to food preservatives]

Chemical food preservatives are incorporated into food products with the objective of preventing or delaying microbial spoilage and development of pathogenic microorganisms. In this study the in vitro activity of two esters of para-hydroxybenzoic acid (methyl paraben and propyl paraben) was investigated against 434 staphylococci isolates from healthy people. The agar dilution method was used for studying the antimicrobial activity. The investigated parabens were active against staphylococci with minimum inhibitory concentrations lower than commonly used levels for food preservation.

[New methyl-quinoxaline derivatives with antimicrobial activity]

This paper presents the synthesis of six new quinoxaline derivatives cycloadditions products of N-monoxide and N,N'-dioxide of 6-methyl-quinoxaline. The chemical structure of new azabicyclic products was confirmed by C, H, N elemental analysis and spectral analysis (IR and RMN). We have tested the antimicrobial activity of the new synthesized azabicyclic derivatives by the diffusimetric method. The assay was made on the seven microorganisms, gram-positive and gram-negative bacteria. The results show that the new compounds are more active against the gram-positive bacteria and Candida albicans.

A study for the improvement of the cytological urine examination performances in upper tract infection diagnosis

Diagnosis of the location of upper and lower urinary tract infection (UTI) is necessary in defining the therapeutic conduct that has a different period and intensity according to the infection location and in prognosis. Many studies show the lack of clinical criteria peculiarity in revealing the different location of UTI. As a result, the correct location of the level in which UTI develops is the necessity of paraclinical investigations. Urinary sample examination, in which urinary sediment microscopy is essential, is a reliable technique in fast detection and localization of UTI. Finding, in pyuria context, the classic significant bacteriuria (> or = 10(5) CFU/ml) or lower value bacteriuria (< or = 10(4) CFU/ml) confirms the UTI diagnosis. The upper tract infection prognosis increases when leukocyte cylinders, characteristic for pyelonephritis, appear together with intact or degraded leukocytes, single or grouped. We settled an algorithm to examine the urine samples in order to: Concentrate and preserve the structural integrity of leukocytes and cylinders, examining the conventional urinary sediment Precisely identify and differentiate these elements by vital coloration (leukocyte peroxidase coloration and Sternheimer - Malbin coloration) to establish more accurate the UTI level. The vital coloration for leukocyte peroxidase has cytological specificity, confirming the pyuria and the cylinders that contain leukocytes (leukocytary, granular, mixed) and obviously ameliorates the reliability and reproducibility of the urinary sediment cytological exam.

[Activity of fourth generation cephalosporins against clinical isolates of Enterobacteriaceae]

Cefpirome and cefepime are a novel group of cephalosporins which contain a positively charged quaternary ammonium at carbon 3 of the dihidrothiazone ring. The antimicrobial agents cefpirome, cefepime, cefotaxime, ceftriaxone, ceftazidime, cefoperazone and imipenem were tested against clinical isolates of Escherichia coli (n = 302) and Klebsiella spp. (n = 62) obtained during september-december 2002 from patients of Galaţi Emergency Hospital. The fourth generation cephalosporins cefpirome and cefepime have similar in vitro activities to the third generation cephalosporins. E. coli showed the comparable resistance rates for all cephalosporins. Against Klebsiella spp. strains cefpirome was less active (35.5% resistance) than cefepime (25.8% resistance). As expected, imipenem had excellent activity (100% susceptibility).

[In vitro antibacterial activity and beta-lactamase stability of meropenem]

The comparative activity of meropenem with that of imipenem, cefotaxime, ceftriaxone and ceftazidime against 856 gram-negative bacilli was studied studied by an agar dilution method. Meropenem and imipenem were high active against tested strains. Resistance to third generation cephalosporins was high for most microorganisms tested. For rapid detection of metallo-beta-lactamase (MBL)-producing gram-negative bacilli a simple disk diffusion test was used. EDTA, FeCl2 and CuCl2 were evaluated as IMP-1 inhibitors. The method is helpful for screening of IMP-1 producers in daily clinical activity.

In vitro susceptibility of staphylococci to linezolid and other antimicrobial agents

Linezolid is a member of the new class of antibacterial agents called oxazolidinones that are active against Gram positive organisms and exert their action by protein synthesis inhibition. In this study we investigated the in vitro activity of linezolid versus the other agent against clinical strains of staphylococci: Staphylococcus aureus (n = 82) and S. epidermidis (n = 32) collected in 2002 from hospitalized patients and healthy individuals, isolated from different biological samples. Agar dilution minimum inhibitory concentrations (MICs) were determined by using Mueller-Hinton agar according to the guidelines established by the National Committee for Clinical Laboratory Standards. Linezolid demonstrated excellent in vitro activity against all isolates tested, with MICs values in the range of susceptibility (< or = 8 microg/ml). No associated resistance between linezolid and other agents tested was observed. The resistance among Gram positive bacteria continues to spread and for many patients infected with these resistant organisms antimicrobial therapy is ineffective and linezolid may be a new alternative treatment.

Resistance pattern of extended-spectrum beta-lactamase producing Enterobacteriaceae isolates

Gram-negative pathogens harboring extended-spectrum beta-lactamases (ESBL) are becoming an increasing therapeutic problem in many wards. The aim of our work was to study ESBL production by Enterobacteriaceae strains from Eastern Romania and their antimicrobial resistance. We selected 54 clinical isolates among 1068 enterobacteria according to their susceptibility spectrum (National Committee for Clinical Laboratory Standards, 1999). Antimicrobial susceptibility tests were performed using the Rapid ATB E gallery of mini API system (BioMérieux) and by a macrodilution method in Mueller-Hinton agar following standard procedure of the National Committee for Clinical Laboratory Standards (NCCLS). ESBL production was established by using both double disk synergy test (DDT) and Expert computer program of mini API. The isoelectric point (pI) was determined by isoelectric focusing in polyacrylamide gel and revealed by nitrocefin. As references we used beta-lactamases with known pI. The Expert computer program of mini API confirms the positive DDT test for all selected strains. Almost all strains displayed resistance to ampicillin, ampicillin/sulbactam or third generation cephalosporins and aztreonam. By IEF we identified 51 strains which have a unique enzyme. IEF pattern showed presence of two enzymes in three Escherichia coli strains. According to our results, the ESBL TEM-type are the most common for the studied isolates. The production of extended-spectrum beta-lactamases and the presence of the multiresistant of antimicrobial agents reflect, probably, the over use of third generation cephalosporins in Eastern Romania.

[Detection of extended-spectrum beta-lactamases production in enterobacteriaceae strains]

Extended-spectrum beta-lactamases (ESBL) cause resistance to ceftazidime, ceftriaxone, cefotaxime and other cephalosporins. The ESBL enzymes are most often derivatives of beta-lactamases from the TEM or SHV group. The aim of our work was to study ESBL production by 35 ceftazidime-resistant strains. We selected these strains among 335 Enterobacteriaceae, isolated in Eastern Romania from healthy carriers and patients, between january-june 1999. To identify the studied strains we used API 20E and API 32E. The ESBL production was established by using both double disk synergy test (DDT) and EXPERT computer program of miniAPI (Bio Merieux). We revealed ESBL production in 26 strains when EXPERT program was used and only 23 when DDT was used. Our results suggest that miniAPI is a better method to study ESBL production than DDT.

Sensitivity of Enterobacteriaceae strains to the third generation cephalosporins

The aim of this study was to evaluate the in vitro activity of cefotaxime, ceftriaxone, ceftazidime, ceftibuten and aztreonam against the clinical isolates of Enterobacteriaceae. MICROORGANISMS: A total of 973 enterobacteria isolated from clinical material (urine and faeces) were tested. Strains were collected during 1996-1998 period, in some centers of Eastern Romania. SENSITIVITY STUDY: MICs were performed using the agar dilution method following standardized techniques (NCCLS, 1994). Stock solutions of antibacterial agents were prepared from their respective powder forms, in concentrations ranging from 0.03 to 128 mg/ml. Our results show a good activity of the tested antimicrobials on Escherichia coli, Shigella spp and Klebsiella spp tested, and reveal a particular behaviour for Salmonella spp, characterized by a heterogenous susceptibility. In conclusion, cefotaxime, ceftriaxone, ceftazidime, ceftibuten and aztreonam were active at low concentrations against tested isolates. Against Salmonella spp, these agents were less active: percent of resistant strains by beta-lactamase production was significant.

Resistance mechanism for a number of non-typhoidic Salmonella strains isolated in Iaşi, Romania

The aim of this study was to find a possible explanation for the resistance pattern of the selected strains and to evaluate the impact in case of isolating such strains. During the period February-March 1998, in the Pediatric Hospital "Sf. Maria" from Iasi, Romania, 12 non-typhoidic Salmonella strains, non-duplicates were isolated from stools of newborns and, in one case, from mother as well. Identification was done by standard methods, and sensitivity testing by disk diffusion method, against the following antimicrobials: Ampicillin (A), Amoxycilin/Clavulanic Acid (AMC), Tetracycline (T), Streptomycin (S), Cloramphenicol (C), Nalidixic Acid (NA), Ciprofloxacin (CIP), Cephalotin (KF), Cefuroxime (CXM), Ceftriaxone (CRO), Cefotaxime (CTX), Ceftazidime (CAZ), Aztreonam (AZT), Imipenem (IPM), Amikacin (AK). All strains showed resistance to: A, AMC, T, S, C, NA, CRO, CAZ, CXM, CTX, KF except one strain, CTX and CRO sensitive. The possible explanation is the production of an extended-spectrum beta-lactamase (ESbLA), detected by microbiological methods (Masuda and clover-leaf). Resistance transfer was realised by using the previously described method. In conjugation experiments we have obtained only one transconjugant, identified as E. coli, that has acquired all resistance determinants. This report highlights on the isolation of multiresistant non-typhoidic Salmonella strains in hospitalised patients without previous antibiotic treatment and possibility of detecting such strains by being aware of the correlation: resistance phenotype-resistance mechanism.

[New isatin-derived hydrazones and Mannich bases with possible biological activity]

The paper presents a synthesis of six new Mannich bases, five hydrazones derived from 1-piperidino-methyl-5-R-isatin and three copper complex compounds of 3-(3'-R-phenyl-pyridazinil-hydrazone)-indoline-2-ones (R=H, CH3, OCH3). The structure of the new compounds was confirmed by the results of the elementary and spectral analysis. Pharmacodynamic studies indicated that copper complex compounds present effective biological properties. Thus, it can be seen that the experimental carrageenan-induced inflammatory oedema was 58.3% inhibited by the complex V (R=CH3) after oral administration. Antimicrobial tests revealed that only compound V (R=OCH3) shows a moderate antimicrobial activity against the gram-positive and gram-negative bacteria, used in the test.