Survey on the diagnosis and treatment of Clostridium difficile infection.

BACKGROUND: The toxigenic strains of Clostridioides (Clostridium) difficile is the most common pathogen of nosocomial and antibiotic-related diarrhoea in healthcare facilities. Lately, there has been an increase in the incidence of C. difficile infection (CDI) cases in Slovakia. MATERIALS AND METHODS: Retrospective analysis of the CDI appearance was carried out in the Zilina region. Additionally, an electronic survey focused on the diagnosis and treatment management of C. difficile infection was conducted among leading clinicians of the wards where CDI was present. RESULTS: Eighty percent of clinicians reported that they were following the recommendations for diagnosis and treatment of C. difficile infection in their everyday practice. The majority of leading physicians were from internal medicine wards (50 %). Most respondents stated that the laboratory results correlated with the clinical symptoms of patients. The first-choice treatment of C. difficile infections was reported to be oral vancomycin (in 21.7 %) and oral metronidazole (in 47.8 %). The estimate of first-choice treatment success rate was 80 %, while the recurrence rate and severe course was observed in 20%. Vancomycin was the standard treatment for recurrent infection. It was administered orally either alone (31 %) or combined with metronidazole (38 %) or fidaxomicin (31 %). CONCLUSION: The results of the survey showed that recommendations for the diagnosis and treatment were implemented in the wards of hospitals and showed the awareness of the necessity of rapid diagnosis and early treatment of C. difficile infection in patients (Fig. 4, Ref. 30).

Identification of Mycobacterium Species by MALDI-TOF Mass Spectrometry.

Matrix-assisted laser desorption ionization - time-of-flight (MALDI-TOF) mass spectrometry enables to identify microorganisms by comparison of the protein content with reference spectra in the database. The aim of this study was to evaluate the efficacy of phenotypic identification of mycobacteria by MALDI-TOF mass spectrometry in laboratory practice. Seventy five isolates of mycobacteria were identified by molecular and phenotypic method, and the results were compared by MALDI-TOF. For MALDI-TOF, material was processed according to the Bruker Daltonics protocol and Mycobacterial Library database version 2.0, with 313 reference mycobacteria spectra. All except one of the 72 isolates agreed with regard to the species and genus by both methods. Forty three isolates were identified as the M. tuberculosis complex by MALDI-TOF. Thirty one isolates of nontuberculous mycobacteria were consistently identified by both methods to the species level. We conclude that MALDI-TOF mass spectrometry is an accurate method of bacterial identification. Simplicity, speed, and economic availability of the method makes it suitable for mycobacteria identification in a routine laboratory.

Importance of GOLD Guidelines for Chronic Obstructive Pulmonary Disease.

In December 2011, a major revision of GOLD 2011 guidelines was published based on the evidence-based medicine. The goal of GOLD 2011 is to determine the severity of the disease, its impact on the patient's health, and the risk of future events; all of which eventually guide therapy. A combined COPD assessment according to GOLD 2011 considers the patient's level of symptoms, spirometry abnormalities, risk of exacerbation, and the presence of comorbidities. GOLD 2011 stratifies patients into four basic groups labeled A, B, C, and D. The aim of the present study was to assess the importance of updated GOLD guidelines for the diagnosis, treatment, and prevention of COPD. We found that the multicomponent 2011 guidelines offer a significant advantage over the previous mono-component COPD assessment according to GOLD 2006 in terms of disease control and therapy management, with patients enjoying better spirometry values and a higher arterial oxygen content considered the primary outcomes of interest.

Microbiologic Methods in the Diagnostics of Upper Respiratory Tract Pathogens.

Upper respiratory tract infection (URI) is a nonspecific term used to describe acute infections involving the nose, paranasal sinuses, pharynx, and larynx above the vocal cords. The aim of this study was to provide a summary of the most common pathogens of URI and to compare advantages and disadvantages of traditional and new rapid microbiological tests used to identify them. Blood samples were simultaneously examined by the enzyme-linked immunosorbent assay (ELISA) and by the FilmArray Respiratory Panel for eight different pathogens in a total of 15 tests performed in nasopharyngeal swabs. The ELISA method is unable to identify the pathologic agent until the host's immune system elicits a response. The method is readily available in many laboratories at a low cost, which puts less strain on economic resources. The FilmArray® Panel, on the other hand, is more expensive, but it is fast and exact in the identification of a broad spectrum etiologic agents. Nonetheless, since most repiratory tract infections are viral in origin and there is no treatment available, the diagnosis provided by the FilmArray Panel does not provide any additional clinical benefit and thus should be used only whenever necessary on the individual basis.

Potassium ion channels and allergic asthma.

High-conductive calcium-sensitive potassium channels (BK+Ca) and ATP-sensitive potassium (K+ATP) channels play a significant role in the airway smooth muscle cell and goblet cell function, and cytokine production. The present study evaluated the therapeutic potential of BK+Ca and K+ATP openers, NS 1619 and pinacidil, respectively, in an experimental model of allergic inflammation. Airway allergic inflammation was induced with ovalbumine in guinea pigs during 21 days, which was followed by a 14-day treatment with BK+Ca and K+ATP openers. The outcome measures were airway smooth muscle cells reactivity in vivo and in vitro, cilia beating frequency and the level of exhaled NO (ENO), and the level of pro-inflammatory cytokines in the plasma and bronchoalveolar lavage fluid. The openers of both channels decreased airway smooth muscle cells reactivity, cilia beating frequency, and cytokine levels in the serum. Furthermore, NS1619 reduced ENO and inflammatory cells infiltration. The findings confirmed the presence of beneficial effects of BK+Ca and K+ATP openers on airway defence mechanisms. Although both openers dampened pro-inflammatory cytokines and mast cells infiltration, an evident anti-inflammatory effect was provided only by NS1619. Therefore, we conclude that particularly BK+Ca channels represent a promising new drug target in treatment of airway's allergic inflammation.

Antioxidant activity of herbal polysaccharides and cough reflex.

The extraction of Fallopia sachalinensis leaves resulted in two fractions (FS-1 and FS-2). Chemical and spectral analyses of samples revealed the prevalence of pectic polysaccharides with high galacturonic acid, arabinose, galactose, and rhamnose content. Arabinogalactan with a higher content of phenolic prevailed in the FS-1, whereas rhamnogalacturonan predominated in the FS-2 fraction. Both polysaccharides showed significant antioxidant activity according to DPPH and FRAP assays. Evaluation of antitussive activity in healthy adult conscious guinea pigs after oral application of 50 and 75 mg/kg of the FS-2 polysaccharide extracts showed a significant suppression of cough reflex, without an influence on specific airway resistance. The suppression of cough was comparable with that of codeine.

Experimental model of allergic asthma.

The aim of the study was to prepare and evaluate the experimental model of allergic asthma. Changes in chough reflex, bronchoconstriction and the degree of inflammation were studied in ovalbumin (OVA) sensitized guinea pigs after 0, 7, 14, 21 days of exposure. The cough reflex was induced by citric acid inhalation in conscious animals in a double chamber body plethysmograph. Tracheal smooth muscle reactivity was assessed by examining the in vitro response to histamine (H) (10(-8)-10(-3) mol/l) and in vivo to H nebulization (10(-6) mol/l). BALF levels of IL-4, IL-5 and the eosinophil count were used as parameters of airway inflammation. After 7 days of OVA sensitization, there was an increase in tracheal smooth muscle contractility in vitro to cumulative concentration of H and an increase in cough parameters. After 14 days of OVA sensitization, there was a further increase in tracheal smooth muscle contractility to H, an increase in airway resistance, and a small increase in cough parameters. After 21 day of OVA sensitization, cough parameters were significantly reduced, airway resistance after H inhalation was increased, and there were significant increases in IL-4, IL-5, and eosinophils in BALF. In conclusion, progress in asthmatic inflammation during 21-day OVA sensitization caused a gradual increase in inflammatory mediators, a decline in cough reflex, and enhanced bronchoconstriction. This experimental model of allergic asthma can be used for pharmacological modulations of defense reflexes and inflammation.

Polyphenols and their components in experimental allergic asthma.

The aim of the study was to investigate the potential anti-inflammatory effects in -experimental allergic asthma of natural polyphenolic compounds or their single major components. The experiment was performed after 21-days sensitization of guinea pigs with ovalbumin suspension. Changes in airway reactivity after the long-term treatment with the polyphenolic compounds Provinol and Flavin-7 and their single major components quercetin and resveratrol during were assessed using a whole body plethysmography. Reactivity of tracheal smooth muscle was studied in vitro in response to cumulative doses of the bronchoconstrictive mediators histamine and acetylcholine. Furthermore, concentrations of the inflammatory cytokines IL-4 and IL-5 were measured in bronchoalveolar lavage fluid. The results demonstrate significant anti-inflammatory effects of Provinol and Flavin-7 exerted in the airways. In contrast, chronic treatment with quercetin and resveratrol, single components of the two polyphenols, did not show such activity. We conclude that polyphenolic compounds are more effective in the anti-inflammatory effects in the airways than their separate components.

Acute bronchodilator effect of quercetin in experimental allergic asthma.

OBJECTIVES: The aim of our study was to investigate the acute effect of quercetin on experimental allergic asthma after single-dose oral administration. BACKGROUND: Airway hyperresponsiveness is one of the main features of allergic asthma. None of quercetin experimental studies analysed the acute effect of this flavonol on the reactivity of airways both, in vivo and in vitro conditions. METHODS: Our experiment was realized 21 days after the sensitization of guinea pigs with ovalbumin suspension. Changes in the reactivity of airways were studied using the whole body plethysmography in order to compare changes of the specific airway conductance between groups with and without quercetin treatment. Also changes in the reactivity of the tracheal smooth muscle dipped into the organ bath with Krebs-Henseleit solution were measured as the reaction on cumulative doses of the bronchoconstrictor mediators histamine and acetylcholine. Quercetin was added into the solution 30 minutes before the chemical mediators. The amplitude of tracheal smooth muscle precontracted with histamine or acetylcholine was used as a tracheal smooth muscle reactivity parameter in vitro. RESULTS: Our results showed that quercetin (20 mg/kg) caused significant bronchodilation, both in vivo and in vitro. CONCLUSION: Quercetin proved in laboratory conditions its ability to reduce hyperreactivity of airways as one of the main attribute of allergic asthma (Fig. 2, Ref. 23).

The relationship between dose-dependent antitussive and bronchodilatory effects of Opilia celtidifolia polysaccharide and nitric oxide in guinea pigs.

A crude polysaccharide composed of uronic acids (32%), arabinose (26%), glucose (15%), galactose (11%), rhamnose (7%), mannose (5%), xylose (4%) and small amount of fucose residues has been isolated from the leaves of Opilia celtidifolia by boiled water extraction. Chemical analyses of Opilia polysaccharide revealed the prevalence of a pectin material with high arabinose and galacturonic acid contents. Opilia polysaccharide showed significant biological effects on chemically induced cough reflex and reactivity of airways smooth muscle in vitro and in vivo conditions in guinea pigs test system. Tests confirmed the dose-dependent cough-suppressive effect of Opilia polysaccharide comparable with activity of centrally acting codeine. Further, the bronchodilatory tests resulted in significant decrease in the values of specific airway resistance, which is very sensitive predictor of airway smooth muscle reactivity in vivo conditions regardless of bronchoconstricting mechanism. The results of in vitro experiments confirmed not only the bronchodilatory effect Opilia polysaccharide but revealed that its bronchodilatory mechanism is partially accompanied with enhanced NO production.

Side effects of anastrozole in the experimental pre-menopausal mammary carcinogenesis.

UNLABELLED: The aim of this study was to assess side effects of aromatase inhibitor anastrozole in the prevention of N-methyl-N-nitrosourea - induced pre-menopausal mammary carcinogenesis in female Sprague-Dawley rats. This model mimicked situation in healthy, but from the point of view of the development of breast cancer, high-risk pre-menopausal women.

Aromatase inhibitor anastrozole was used as a chemopreventive agent taken by the animals in the food during the whole period of time of the experiment. Group 1 - the control group had taken food without anastrozole, the groups 2 and 3 with anastrozole in various concentrations - 0.05 mg/1 kg of food (ANA 0.05) and 0.5 mg/1 kg of food (ANA 0.5).

In anastrozole-treated animals in comparison with untreated animals, macroscopic changes of uterus and vagina were not found. The values of absolute and relative wet weight of uterus and vagina in the groups ANA 0.05 and ANA 0.5 were comparable with the control. Histological examination did not show atrophic changes in endometrium of uterus and in epithelium of vagina in anastrozole-treated animals. In the group ANA 0.5 myometrium was significantly grosser than in the group ANA 0.05 (P<0.05). Anastrozole neither affects parameters of plasma lipid metabolism (triacylglycerols, total cholesterol, low - density lipoprotein cholesterol and high - density lipoprotein cholesterol) nor serum levels of sex hormones (estradiol, testosterone, dehydroepiandrosterone). Compact bone thickness in the groups with anastrozole was significantly increased in comparison with untreated animals (P<0.001). A significant increase in body weight was found in the group ANA 0.5 compared with the control group (P<0.01). The significant increase in body weight gain was not attended by the significant increase in food intake.

The side effects of aromatase inhibitor anastrozole in the prevention of N-methyl-N-nitrosourea - induced pre-menopausal mammary carcinogenesis in female Sprague-Dawley rats on myometrium, compact bone thickness and body weight gain were observed.

Neoplastic effects of exemestane in premenopausal breast cancer model.

Aromatase inhibitor exemestane as a single - agent has no established role in the treatment of premenopausal breast cancer women. The aim of this study was to evaluate preventive effects of exemestane in the model of premenopausal Nmethyl- N-nitrosourea - induced mammary carcinogenesis in female rats. Exemestane treatment begun 7 days prior to carcinogen administration and continued next 12 weeks - till the end of experiment. Exemestane was dietary administered in two concentrations of 1 mg / 1kg (EXE 1), or 10 mg/1 kg (EXE 10), respectively. Exemestane increased the tumor frequency by 80.5 % (P=0.034) in the group EXE 1 and by 61.5 % (P=0.045) in the group EXE 10 in comparison with control animals. In the group EXE 10, the incidence of mammary tumors was increased by 11.5 % (P=0.31) and tumor volume by 41.5 % (P=0.23), also the latency was shortened by 8 days (P=0.078) compared with controls. In the groups with exemestane, changes in weights and histology of uterus and vagina were not found at the end of experiment. Exemestane did not alter serum concentrations of estradiol, testosterone and dehydroepiandrosterone. In the group EXE 10 in comparison with untreated animals, exemestane decreased serum concentrations of triacylglycerols by 9 % (P=0.032), total cholesterol by 19.5 % (P=0.0002) and cholesterol of low - density and high - density lipoprotein fractions by 41 % (P<0.0001), or 21.5 % (P=0.0002), respectively. In the group EXE 1, the decrease in cholesterol of low-density lipoprotein fraction by 22.5 % (P=0.0005) was recorded. An increase in food intake (P=0.023) and body weight gain (P=0.036) was found in the group EXE 10 compared with the control group (P<0.05). The present study points to apparent tumor - promoting effects of dietary administered exemestane in the model of premenopausal mammary carcinogenesis in female rats. Exemestane as a steroidal agent indicated androgenic effects on rat lipid metabolism in this experiment.

Preventive effects of letrozole in the model of premenopausal mammary carcinogenesis.

Single - agent therapy with aromatase inhibitors has no established role in premenopausal women with breast cancer. In this study, tumor suppressive effects of letrozole in the prevention of N-methyl-N-nitrosourea - induced mammary carcinogenesis in female Sprague-Dawley rats were evaluated. Letrozole was dietary administered in two concentrations - 1 mg/1 kg (LETRO 1), and 10 mg/1 kg (LETRO 10). Letrozole suppressed incidence of mammary gland cancer by 93 % (P<0.00002) in the group LETRO 1 in comparison with control animals. Total suppression of mammary carcinogenesis was observed in the group LETRO 10. In the groups with letrozole, uterine and vaginal atrophy was found at the end of experiment. In letrozole - treated animals in comparison with untreated animals, increased plasmatic triacylglycerol concentrations (P<0.0001) were observed, but total cholesterol and cholesterol of low- and high- density lipoprotein fractions were not significantly changed. An increase in body weight gain and food intake was found in the groups LETRO 1 and LETRO 10 compared with the control group (P<0.0001). The present study points to high tumor suppressive effects of letrozole in premenopausal model of mammary carcinogenesis in female rats.

Aromatase inhibitors in the breast cancer therapy and their potential using in the prevention setting.

Long term exposure to estradiol is associated with an increased risk of breast cancer. Aromatase inhibitors, suppressing tumour and plasma estrogen levels by blocking conversion of testosteron to estrogen, have been proven to provide the most effective endocrine therapy in metastatic and adjuvant setting in postmenopausal women. Questions remains about the long term side effects and safety profile of aromatase inhibitors. The effectiveness and safety of aromatase inhibitors therapy in premenopausal breast cancer patients is unknown, this needs to be further investigated. Although tamoxifen represents the gold standard for prevention therapy at present, results of ongoing studies may indicate a role of aromatase inhibitors in prevention of breast cancer (Tab. 2, Ref. 22).