Antimicrobial Effect of 0.2% Chlorhexidine in Infected Root Canals

The aim of this study was to identify bacteria from the infected root canals of teeth with chronic apical periodontitis, and to evaluate the antibacterial effect of 0.2% chlorhexidine (CHX), as an irrigant, in reducing the microbial flora 48h after root canal preparation. A total of 44 subjects were randomly divided in the experimental group and the control group. The first bacterial samples from all root canals were obtained in the beginning, before any treatment. During mechanical instrumentation, root canals were irrigated three times, with 0.2% CHX in the experimental group, and with saline solution in the control group. All canals were dried and temporarily sealed with zinc oxide-sulfate cement. After 48h the second samples were obtained. Bacterial samples were subjected to microbiologic processing. The study indicates that 0.2% CHX is significantly effective in reducing the microbial flora, and could be used as an irrigant solution

Detection of virulence gene belonging to cag pathogenicity island in Helicobacter pylori isolates after multiple unsuccessful eradication therapy in Northwest Croatia

Background: Some of the genes belonging to cag pathogenicity island (cagPAI) in Helicobacter pylori were found to be associated with an increased severity of gastric mucosal inflammation that might lead to the development of gastroduodenal disease. Aim: The aim of our study was to define a group of patients based on the frequency of virulence genes of cagPAI island and comparison with pathohistological alterations of gastric mucosa who need to be subjected to further eradication therapy after previous unsuccessful eradication therapy and in spite of benign endoscopic findings. Material and methods: In total 103 H. pylori isolates were analysed. Genes encoding virulence factors were detected by PCR with primers for 10 loci in cagPAI: Apcag (cagA promotor region), cagA1, cagA2, cagA3, cagM, cagT, cagE, LEC, tnpA and tnpB. The patients who provided isolates were classified into three clinical categories: non-ulcer dyspepsia (n=69), erosio/ulcus ventriculi (n=22) and erosio/ulcus duodeni (n=12). Results: 16 strains (15.5%) were negative for all tested genes. 87 (84.5%) of the isolates had parcially deleated cagPAI. None of the isolates possessed all 10 genes. The frequency of single cagPAI genes were as follows: Apcag 63.1%, cagA1 71.8%, cagA2 69.9%, cagA3 5.8%, cagM 71.8%, cagE 75,7%, cagT 68%, tnpA 9.7%, tnpB 7.8% i LEC 48.5%. No statistically significant difference was observed between the presence of any cagPAI genes and endosopic diagnosis (p>0.16). The presence of CagA2, Apcag and cagM showed statistically significant correlation with higher level of patohistological parameters of gastritis (p<0.05). Conclusions: H. pylori isolates with positive cagA, Apcag and cagM genes are correlated to higher degree of patohistological lesions of gastric mucosa; without statistically significant correlation with endoscopic diagnosis

Emergence of Uropathogenic Extended-Spectrum b Lactamases-Producing Escherichia coli Strains in the Community

The aim of this study was to determine the virulence characteristics and resistance pattern of the extended-spectrum b lactamases (ESBLs)-producing Escherichia coli strains isolated from urine of outpatients in the Zagreb region during a five-month period, and to compare them with the non ESBLs-producing E. coli strains isolated in the same period. Out of 2,451 E. coli strains isolated from urine of nonhospitalized patients with significant bacteriuria, a total of 39 ESBLsproducing strains (1.59%) were detected by a double-disk diffusion technique and by the broth-dilution minimal inhibitory concentration reduction method. The 45 non ESBLs-producing strains were randomly chosen, and phenotype of the two groups of strains was characterized and compared. Serogroup O4, hemolysin production, expression of P- and type 1 fimbriae as well as resistance to gentamicin and amikacin were significantly more prevalent characteristics among the ESBLs-producing strains than among non ESBLs-producing strains (p<0.01), while higher prevalence of trimethoprim- sulfamethoxazole resistance among ESBLs-producing strains was not statistically significant (p>0.05). Chromosomal DNA analysis by pulsed-field gel electrophoresis exhibited a great genomic similarity among ESBLs-producing strains and revealed that those highly virulent and resistant E. coli strains isolated from urine of outpatients in the Zagreb region had a clonal propagation

Učestalost humanog papilomavirusa 16 i Epstein-Barrova virusa kod bolesnika s oralnim karcinomom pločastih stanica

It has been suggested that certain viruses such as human papillomaviruses (HPV) and Epstein-Barr virus (EBV) might have a role in oral squamous cell carcinoma (OSCC). However, results of the published studies are controversial and are dependent on the geographic distribution and methods of sampling and sample analysis. The aim of this study was to determine the prevalence of HPV 16 and EBV in OSCC patients. In 24 patients with OSCC (mean age 59.6±8.8) and 30 controls (mean age 49.1±8.3), 5 mL of blood was collected to determine the prevalence of EBV by serologic methods. In addition, swabs were obtained to analyze the presence of HPV 16 and EBV by use of polymerase chain reaction. Statistical analysis was performed by use of Mann Whitney test, χ2-test and Spearman correlation test. The results of this study showed that there were no significant differences between OSCC patients and control subjects according to the presence of EBV or HPV 16. Therefore, it can be concludedČini se kako određeni virusi poput humanih papilomavirusa (HPV) i Epstein-Barrova virusa (EBV) mogu imati ulogu u nastanku karcinoma pločastih stanica u usnoj šupljini (OPCK). Ipak, rezultati objavljenih istraživanja na tu temu su kontroverzni i ovise o geografskoj distribuciji i metodama uzimanja uzoraka odnosno raščlambi uzoraka. Cilj ovoga istraživanja je bio odrediti učestalost HPV 16 i EBV u osoba s OPCK. U 24 osobe s OPCK (srednje dobi 59,6±8,8) i u 30 kontrolnih ispitanika (srednje dobi 49,1±8,3) je uzeto 5 mL krvi kako bi se odredio EBV serološkim metodama. Uz to su uzeti i brisevi kako bi se odredila prisutnost HPV 16 i EBV uz pomoć reakcije lančane polimeraze. Statistička analiza je napravljena pomoću Mann-Whitneyeva testa, χ2-testa i Spearmanova korelacijskog testa. Rezultati ovoga istraživanja pokazuju kako nije bilo znakovitih razlika između osoba s OPCK i kontrolnih ispitanika s obzirom na prisutnost HPV 16 ili EBV. Može se zaključiti kako ovi virusi u našoj populaciji oboljelih od OPCK vjerojatno nemaju veliku ulogu

Value of Rapid Aetiological Diagnosis in Optimization of Antimicrobial Treatment in Bacterial Community Acquired Pneumonia

In 80 adult patients with community acquired pneumonia (CAP) conventional microbiological methods, polymerase chain reaction (PCR) and serum C-reactive protein (CRP) levels were performed and the appropriateness of the empirical antimicrobial treatment was evaluated according to bacterial pathogen detected. The aetiology was determined in 42 (52.5%) patients, with Streptococcus pneumoniae as the most common pathogen. PCR applied to bronchoalveolar lavage (BAL) provided 2 and PCR on sputum samples 1 additional aetiological diagnosis of CAP. The mean CRP values in the S. pneumoniae group were not significantly higher than in the group with other aetiological diagnoses (166.89 mg/L vs.160.11 mg/L, p=0.457). In 23.8% (10/42) of patients with determined aetiology, the empirical antimicrobial treatment was inappropriate. PCR tests need further investigation, particularly those for the atypical pathogens, as they are predominant in inappropriately treated patients. Our results do not support the use of CRP as a rapid test to guide the antimicrobial treatment in patients with CAP

Molecular Variants of Human Papilloma Viruses Type 16 and 6 in Women with Different Cytological Results Detected by RFLP Analysis

HPV infections are common and the presence of the same high-risk type in cervical specimens can be due to reinfection or persistence. Persistent infection is the most important predictor for development of cervical carcinoma. The aim of this study was to validate PCR-RFLP with two sets of primers: MY09/MY11 that amplify a fragment of L1 and P1/P2 that amplify a fragment of E1 ORF. PCR product of MY09/MY11 was digested with a set of 6 restriction enzimes (RE) and PCR product of P1/P2 with a set of 12 RE. Cervical samples from 110 women patients of the University Gynecologic Clinic CHC Zagreb were analyzed. There were 98 (89.1%) PCR positive samples detected with P1/P2 primers, and 94 (85.5%) PCR positive samples detected with MY09/MY11 primers. Seven HPV types were detected with P1/P2-RFLP technique and 17 with MY09/MY11-RFLP. PCR positive samples amplified with both primer pairs agreed with each other in 82 samples; 16 samples were only positive with P1/P2 and 12 samples were only positive by MY09/MY11. HPV 16 was detected in 39 samples with MY09/11-RFLP, out of these two variants (two different patterns) were found with P1/P2 using Dde I, Hae III and Eco I. HPV 6 was detected in 9 samples with MY09/11-RFLP, out of these two variants were found with P1/P2 using HinfI. Combining these two PCR-RFLP methods subtypes of HPV 16 and HPV 6 were detected

Emergence of Uropathogenic Extended-Spectrum b Lactamases-Producing Escherichia coli Strains in the Community

The aim of this study was to determine the virulence characteristics and resistance pattern of the extended-spectrum b lactamases (ESBLs)-producing Escherichia coli strains isolated from urine of outpatients in the Zagreb region during a five-month period, and to compare them with the non ESBLs-producing E. coli strains isolated in the same period. Out of 2,451 E. coli strains isolated from urine of nonhospitalized patients with significant bacteriuria, a total of 39 ESBLsproducing strains (1.59%) were detected by a double-disk diffusion technique and by the broth-dilution minimal inhibitory concentration reduction method. The 45 non ESBLs-producing strains were randomly chosen, and phenotype of the two groups of strains was characterized and compared. Serogroup O4, hemolysin production, expression of P- and type 1 fimbriae as well as resistance to gentamicin and amikacin were significantly more prevalent characteristics among the ESBLs-producing strains than among non ESBLs-producing strains (p<0.01), while higher prevalence of trimethoprim- sulfamethoxazole resistance among ESBLs-producing strains was not statistically significant (p>0.05). Chromosomal DNA analysis by pulsed-field gel electrophoresis exhibited a great genomic similarity among ESBLs-producing strains and revealed that those highly virulent and resistant E. coli strains isolated from urine of outpatients in the Zagreb region had a clonal propagation

COMPARATIVE URINARY BACTERICIDAL ACTIVITY OF ORAL ANTIBIOTICS AGAINST GRAM-POSITIVE PATHOGENS

U kliničkim bakteriološkim laboratorijima antibakterijska aktivnost plazme određuje se in vitro testiranjem, obično disk-difuzijskom metodom. Međutim treba uzeti u obzir da in vitro testiranje ne odražava uvijek djelotvornost antibiotika in vivo. U ovom istraživanju ispitana je baktericidna aktivnost uzoraka urina dobivenih nakon peroralne primjene pojedinačne doze oralnog antibiotika prema relevantnim gram-pozitivnim urinarnim patogenima. Linezolid je imao zadovoljavajuće baktericidne titrove tijekom cijelog razdoblja testiranja prema svim testiranim gram-pozitivnim kokima, dok su fluorokinoloni pokazivali visoku i perzistentnu baktericidnu aktivnost prema stafilokokima, a znatno slabiju aktivnost prema enterokokima. Prema rezultatima ex vivo pokusa, amoksicilin bi se mogao preporučiti kao lijek izbora jedino za infekcije koje uzrokuje Enterococcus faecalis. Amoksicilin u kombinaciji s klavulanskom kiselinom mogao bi se razmatrati kao terapijska opcija kod infekcija koje uzrokuju Staphylococcus saprophyticus i E. faecalis. Testirani stariji cefalosporini pokazali su se djelotvornima samo prema S. saprophyticus. Njihov je nedostatak kratko poluvrijeme eliminacije u urinu, što rezultira brzim sniženjem urinarnih baktericidnih titrova tijekom ispitivanog razdoblja. Nadalje, nemaju aktivnost prema enterokokima zbog njihove intrinzične rezistencije na cefalosporine.In routine bacteriological laboratories the antibacterial activity of antibiotics is determined by in vitro testing, usually by disk-diffusion test. However, in vitro testing does not always reflect antibacterial efficiency of antibiotics in vivo. In this investigation, the urine samples obtained in a single oral dose pharmacokinetic study were examined for their bactericidal activity against a range of relevant Gram-positive urinary tract pathogens. Urinary bactericidal activity of linezolid had been previously compared with ciprofloxacin but not with other oral antibiotics such as b-lactams. Linezolid showed satisfactory urinary bactericidal titres throughout the whole testing period against all Gram-positive cocci. Fluoroquinolones displayed high and persisting levels of urinary bactericidal activity against staphylococci, but their activity against enterococci was weaker. According to the results of ex-vivo testing amoxycillin could be recommended only for infections caused by E. faecalis. Amoxycillin combined with clavulanic acid can be considered as a therapeutic option for infections caused by S. saprophyticus and E. faecalis. Older cephalosporins had high titres only against S. saprophyticus. Their drawback is a short elimination half-time in urine resulting in rapid decrease of urinary bactericidal titers during dosing interval. Furthermore, they do not show activity against enterococci due to their intrinsic resistance to cephalosporins