Immunogenicity and functional characterization of Leishmania-derived hepatitis C virus envelope glycoprotein complex.

Hepatitis C virus (HCV) envelope glycoproteins E1 and E2 are the main inducers of a cross-neutralizing antibody response which plays an important role in the early phase of viral infection. Correctly folded and immunologically active E1E2 complex can be expressed in mammalian cells, though the production process might still prove restrictive, even if the immunological response of a vaccine candidate is positive. Here, we report a characterization and immunogenicity study of a full-length (fE1E2) and soluble version of the E1E2 complex (tE1E2) from genotype 1a, successfully expressed in the cells of Leishmania tarentolae. In a functional study, we confirmed the binding of both Leishmania-derived E1E2 complexes to the CD-81 receptor and the presence of the major epitopes participating in a neutralizing antibody response. Both complexes were proved to be highly immunogenic in mice and elicited neutralizing antibody response. Moreover, cross-reactivity of the mouse sera was detected for all tested HCV genotypes with the highest signal intensity observed for genotypes 1a, 1b, 5 and 6. Since the development of a prophylactic vaccine against HCV is still needed to control the global infection, our Leishmania-derived E1E2 glycoproteins could be considered a potential cost-effective vaccine candidate.

Diagnosis of malignant pericarditis: a single centre experience.

BACKGROUND: Malignancy is the most common cause of effusive pericarditis with a haemodynamically significant amount of pericardial fluid. Early diagnosis and management of malignant pericarditis may significantly improve outcomes. AIM: To evaluate retrospectively the rate and clinical presentation of malignant pericarditis among patients undergoing invasive treatment, with a view to identification of optimal diagnostic modalities to distinguish this group among other patients. METHODS: We studied 191 patients (100 men and 91 women, median age 57 years, range 19-88 years) with effusive pericarditis who underwent invasive treatment in the National Institute of Tuberculosis and Lung Diseases in Warsaw in 1982- -2008 due to a significant amount of pericardial fluid and/or echocardiographic evidence of cardiac tamponade. Pericardiocentesis was performed in 93 cases, pericardioscopy in 61 cases, and substernal pericardiotomy in 37 cases. Pericardial fluid was sent for examination in all patients, and a pericardial specimen was obtained in 96 patients. The patients were divided into 3 groups: Group 1 included patients with malignant pericarditis (malignant cells found in the cytological examination of the pericardial fluid and/or neoplastic infiltration in the histological examination of the pericardial specimen), Group 2 included patients with probable malignant pericarditis (pericardial fluid without malignant cells with histologically confirmed malignancy at some other location), and Group 3 included patients with non-malignant pericarditis (negative cytological examination of pericardial fluid and histological examination of the pericardial specimen, with no evidence of malignancy during hospitalization and one-year follow-up). RESULTS: Malignancy was found in 111 (58%) of 191 patients, including 66 (35%) patients with definite malignant pericarditis and 45 (23%) patients with probable malignant pericarditis. Lung cancer, including adenocarcinoma, was the most common type of malignancy, present in 44 (67%) patients. Non-malignant pericarditis was found in 80 (42%) patients. Among patients with the diagnosis of malignancy (Groups 1 and 2), a positive result of the cytological examination of the pericardial fluid was obtained in 52 cases (sensitivity of 46%). Among patients without malignancy, a negative result of the cytological examination of the pericardial fluid was obtained in all 80 cases (specificity of 100%). Malignant infiltration was found in 20 of 44 patients with the diagnosis of malignancy (sensitivity of 46%) and in none among 52 patients without malignancy (specificity of 100%). Compared to patients with non-malignant pericarditis, patients with malignant pericarditis significantly more commonly presented with tachycardia of >100 bpm in a resting electrocardiogram (ECG) (in 77% of patients with malignant pericarditis vs. 43% of patients with non-malignant pericarditis, p = 0.01), low QRS amplitude (52% vs. 34%, respectively, p = 0.03), electrical alternans (19% vs. 3%, respectively, p = 0.001), echocardiographic evidence of cardiac tamponade (67% vs. 34%, respectively, p = 0.0001), enlarged mediastinal lymph nodes by chest computed tomography (CT) (90% vs. 29%, respectively, p <0.00001), pericardial thickness >8 mm by chest CT (62% vs. 16%, respectively, p <0.0001), and bloody pericardial effusion (94% vs. 43%, respectively, p <0.0001). Levels of carcinoembryonic antigen (CEA) and cytokeratin fragment-19 (CYFRA 21-1) in the pericardial fluid were higher in patients with malignant pericarditis compared to patients with non-malignant pericarditis, with median values of 40.8 ng/mL vs. 0.9 ng/mL, p <0.0001, and 162.85 ng/mL vs. 13.35 ng/mL, p <0.0001, respectively. CONCLUSIONS: 1. Malignancy was found in 58% of patients undergoing invasive treatment due to large pericardial effusion. 2. Cytological examination of the pericardial fluid and histological examination of a pericardial specimen showed high specificity (100%) but low sensitivity (46%) in the diagnosis of malignant pericarditis. 3. The most important predictors of malignant pericarditis included tachycardia of >100 bpm as revealed by the physical examination and ECG, echocardiographic evidence of cardiac tamponade, presence of enlarged mediastinal lymph nodes (>1 cm) and thickened pericardium (>8 mm) by chest CT, bloody pericardial effusion, and elevated levels of CEA (>5 ng/mL) and CYFRA 21-1 (>50 ng/mL) in the pericardial fluid.

Web-based surveillance and global Salmonella distribution, 2000-2002.

Salmonellae are a common cause of foodborne disease worldwide. The World Health Organization (WHO) supports international foodborne disease surveillance through WHO Global Salm-Surv and other activities. WHO Global Salm-Surv members annually report the 15 most frequently isolated Salmonella serotypes to a Web-based country databank. We describe the global distribution of reported Salmonella serotypes from human and nonhuman sources from 2000 to 2002. Among human isolates, S. Enteritidis was the most common serotype, accounting for 65% of all isolates. Among nonhuman isolates, although no serotype predominated, Salmonella enterica serovar Typhimurium was reported most frequently. Several serotypes were reported from only 1 region of the world. The WHO Global Salm-Surv country databank is a valuable public health resource; it is a publicly accessible, Web-based tool that can be used by health professionals to explore hypotheses related to the sources and distribution of salmonellae worldwide.

[Neoplastic pericarditis--the role of different diagnostic procedures]. / Ocena przydatnosci róinych metod diagnostycznych dla rozpoznawania zajecia osierdzia przez proces nowotworowy.

The aim of the study was to assess the role of different diagnostic procedures in the recognition of malignant pericarditis. Consecutive medical records of the patients with pericardial effusion treated with pericardiocentesis or pericardioscopy in the period of 1982-2002 were analyzed retrospectively. Criteria of neoplastic pericarditis were: positive result of pericardial fluid cytology and/or neoplastic infiltration found in pericardial biopsy specimen. Criteria of non-neoplastic pericarditis were: negative result of pericardial fluid cytology and pericardial biopsy specimen, no neoplastic disease diagnosed at presentation and during 3-years of follow up. Malignant pericarditis was diagnosed in 47 patients (pts), nonmalignant in 51. Echocardiographic signs of cardiac tamponade were found in 80% of pts with neoplastic pericarditis and 40% of pts with non-malignant disease (p = 0.0001). Chest CT scan revealed the presence of enlarged mediastinal lymph nodes in 94% of pts with malignant pericarditis and only 11% of pts with non-malignant disease (p = 0.00001). Pericardial thickness on CT scan exceeded 8 mm in 75% of the pts with malignant pericarditis and 8% of pts with nonmalignant disease (p = 0.0003). Pericardial fluid (pf) CEA concentration was significantly higher in the patients with neoplastic pericarditis than in the pts with non-malignant process. CEA > 5 ng/ml and Cyfra 21-1>50 ng/ml were found in 43% of the pts with malignant pericarditis and none of the pts with benign pericarditis. Thus we recommend chest CT scan and pericardial fluid tumor markers (CEA and Cyfra 21-1) assessment as the procedures helpful in the recognition of malignant pericarditis.

[The occurrence and characterisation of oxy-imino-beta-lactams resistant strains among Salmonella enterica subsp. enterica isolated in Poland]. / Wystepowanie i charakterystyka szczepów opornych na antybiotyki oksy-imino-betalaktamowe wsród szczepów Salmonella enterica subsp. enterica izolowanych w Polsce.

Extended-spectrum beta-lactamases (ESBLs) are enzymes manifesting considerable hydrolyzing activity on a wide variety of beta-lactam antibiotics including oxyiminocephalosporins and aztreonam. In the study reported here we investigated the types of ESBL produced by Salmonella enterica subsp. enterica strains isolated from clinical samples in the microbiological laboratories of sanitary-epidemiological units in Poland from 1999 to 2004. Among 239 ampicillin-resistant Salmonella enterica subsp. enterica strains isolated from clinical samples in the microbiological laboratories of sanitary-epidemiological units in Poland, 68 isolates of oximino-beta-lactams resistant of 6 serovars were found. There were 16 epidemiological unrelated strains (6 isolates of S. Enteritidis, 5 isolates of S. Thompson, 3 isolates of S. Typhimurium, one-fold isolate of S. Muenster and S. enterica 1,9,12:-:-) coming from different areas of country and 52 epidemiologically related isolates of S. Oranienburg, coming from a prolonged outbreak in an orphanage in Lódz. All the strains were identified as the ESBLs producers. The molecular analysis revealed that most of them expressed CTX-M-3 ESBL which is widely observed in Poland and additional enzyme TEM-1. All tested isolates of S. Thompson and one of three S. Typhimurium isolates were found to produce SHV-5 ESBL. This is the first report regarding the presence of SHV-5 in the genus Salmonella in Poland.

[PCR-restriction fragment length polymorphism assay (PCR-RFLP) as an useful tool for detection of mutation in gyrA gene at 86-THR position associated with fluoroquinolone resistance in Campylobacter jejuni]. / Wykorzystanie techniki PCR-RFLP do wykrywania mutacji w kodonie 86 genu gyrA zwiazanej z opornoscia na fluorochinolony paleczek Campylobacter jejuni.

The aim of this study was to investigate the mutations in gyrA gene at Thr-86 position in fluoroquinolone resistant C. jejuni clinical isolates (2003-2005). The change of Thr to Ile at 86 position is associated with high-level resistance to fluoroquinolone in C. jejuni. Thirty five (58%) of 65 C. jejuni strains were found to be resistant to ciprofloxacin using E-test method. PCR-RFLP technique with the RsaI enzyme was used for the identification of mutation in gyrA gene. The primers spanning a part of the fluoroquinolone resistance determining region (QRDR) were designed based on the article of Alonso et al. and the gyrA sequence of C. jejuni (Gen Bank accession number LO4566). One of this primer had mismatch introduced at the second nucleotide from 3' end of the primer what gives an artificial RsaI cleavage site. All of the ciprofloxacin-resistant isolates contained a single)point mutation in the gyrA gene: the replacement of Thr 86 by Ile. The results showed that PCR-RFLP is a rapid and simple method for the detection of the high-level fluoroquinolone resistance in C. jejuni.

[Phage types and plasmid profiles of plasmid DNA strains of Salmonella enterica subsp. enterica ser. Enteritidis (S. Enteritidis) isolated from food poisoning outbreaks in 2001]. / Typy fagowe oraz profile plazmidowego DNA szczepów Salmonella enterica subsp. enterica ser. Enteritidis (S. Enteritidis) izolowanych z ognisk zatruc pokarmowych w roku 2001.

Salmonella Enteritidis strains are the most often isolated Salmonella serovar in Poland. In the present study, phage typing, antibiotic resistance testing and plasmid profile analysis, have been applied to characterise 41 Polish S. Enteritidis isolates originated from human cases of salmonellosis and from other sources. The typing phages of Ward and colleagues scheme were used to type a total of 41 S. Enteritidis strains coming from Poland. All 41 strains were typable and 5 different phage types were observed. Among 41 strains tested, both PT6 and PT21 were recognized in the 15 strains (36.6%). Nine strains (22%) belonged to phage type 8. The others PTs were represented by small amount of strains (PT1var and PT4). Among all tested isolates only 4 different plasmid profiles were observed. Of the 41 strains investigated, 16 (39%) contained the 57 kb plasmid alone. The remaining 25 strains (61%) except 57 kb plasmid, possessed additional DNA particles. The probable phage type conversion of PT21 to PT1var strain, possibly connected with smaller DNA particle presence, was observed. This hypothesis needs confirmation. The real S. Enteritidis epidemiological situation in Poland should be known after introducing of systematic, annual research program.