Evaluation of the immunogenic capability of the BCG strains BCGΔBCG1419c and BCGΔBCG1416c in a three-dimensional human lung tissue model

Tuberculosis (TB) still remains as an unmet global threat. The current vaccine is not fully effective and novel alternatives are needed. Here, two vaccine candidate strains derived from BCG carrying deletions in the BCG1416c or BCG1419c genes were analysed for their capacity to modulate the cytokine/chemokine profile and granuloma formation in a human lung tissue model (LTM). We show that the clustering of monocytes, reminiscent of early granuloma formation, in LTMs infected with BCG strains was similar for all of them. However, BCGΔBCG1419c, like M. tuberculosis, was capable of inducing the production of IL-6 in contrast to the other BCG strains. This work suggests that LTM could be a useful ex vivo assay to evaluate the potential immunogenicity of novel TB vaccine candidates.     

Characterization and immune effect of the hepatitis B–BCG combined vaccine for using a needle innoculation

Objective

To prepare the hepatitis B–Mycobacterium bovis Bacillus Calmette-Guérin combined vaccine (HB–BCG combined vaccine) and resolve a needle problem of the two kinds of hepatitis B vaccine (HB vaccine) and M. bovis Bacillus Calmette-Guérin (BCG) for the innoculation.

Methods

The hepatitis B surface antigen (HBsAg) was prepared by the genetic engineering technique, BCG was produced using routine biological technique, and then the finished products of the HB–BCG combined vaccine were processed on the above foundation. The content of HBsAg was measured by Enzyme linked immunosorbent assay (ELISA), the immune effect of BCG was detected by purified protein derivative (PPD) test. Cellular immune response, safety, partial poison and allergy were tested. The stability of HB–BCG combined vaccine was detected by ELISA and viable count method.

Results

The two kinds of antigens (HBsAg and BCG) had good compatibility. The comparison on immune effects of HB–BCG combined vaccine and BCG showed no significant difference. The comparison on immune effects of HB–BCG combined vaccine group (first dose for HB–BCG Combined vaccine, second and third dose for HB vaccine) and HB vaccine group (three dose all for HB vaccine) demonstrated that anti-HBs levels of the HB–BCG combined vaccine group were higher than that of HB vaccine group. No statistical significance was observed between the combined vaccine group and HB vaccine group after three doses immunization schedules. The results of safety in HB–BCG combined vaccine group accorded with that of BCG group, it had been not found the pathological changes of the tuberculosis. The characteristic and process in pathological changes of HB–BCG combined vaccine group and BCG group were similar in the partial poison test. HBsAg did not strengthen the inflammation reaction caused by BCG. Systemic allergy had not been found. The HB–BCG combined vaccine was stable in 2 years.

Conclusion

The immune effects of the HB–BCG combined vaccine were not lower than the two kinds of single dose vaccine, it had good safety.     

Phenotyping and antibiotic susceptibility's study of Neisseria meningitidis strains isolated at the "Hôpital d'Enfants" of Tunis

A total of 23 invasive strains of Neisseria meningitidis were isolated between March 1998 and February 2004. 19 strains were recovered from cerebrospinal fluid (CSF) and 4 from blood. The majority of these strains were recovered from children with an age less to 4 years (86.9%). The antigenic formula'study (serogroup:serotype:serosubtype) of the strain's collection have shown there great diversity. The sero-group B was the most frequent (83%) followed by serogroup C (17%). The B:NT:NST phenotype was major among strains of the serogroup B and the C:4:P1-14 phenotype among strains of the serogroup C. No beta-lactamase activity was detected. 30.4% of the strains were of diminished susceptibility to penicillin G (CM190 = 0.38 Ig/ml). No resistance to amoxicillin (CMI90 = 0.19 microg/ml), to cefotaxime (CMI90 = 0.016 microg/ml) and to rifampin (CMI90-0.125 microg/ml) was detected; whereas 8.7% of strains-were resistant to chloramphenicol (CMI90=2 Ig/ml) and 65.2% to spiramycin.     

Circulation in Italy of β-lactamase-producing strains within the major groups of bacterial pathogens

A multicenter study was undertaken in Italy to assess the circulation of -lactamase-producing organisms and their current incidence within the major groups of bacterial pathogens. Almost four thousand strains, all freshly isolated from clinical material, were examined at four centers serving different areas of Italy. Despite some significant center-to-center differences, this survey documented the occurrence of a large overall circulation of -lactamase-producing organisms among clinical bacterial isolates. In particular, ampicillin resistance was recorded in one third to one half of the isolates of some Enterobacteriaceae, including Escherichia coli, Proteus, and Citrobacter species, and 80–90% of these resistant strains proved to be B-lactamase producers. Both ampicillin resistance and -lactamase production were almost the rule in other Enterobacteriaceae, including Klebsiella, Enterobacter, and Serratia species. -lactamase was also produced by about 80% of glucose-non-fermenting gram-negative bacteria and Aeromonas hydrophila strains, by all of the isolates of Branhamella catarrhalis manifesting ampicillin resistance (i.e. more than half the total number of isolates), and by about two thirds of the ampicillin-resistantffaemophilus strains (which accounted for 20–25% of all Haemophilus isolates examined). In contrast, no B-lactamase producers were observed among Neisseria gonorrhoeae isolates.     

High resolution genotyping of Campylobacter jejuni strains by macrorestriction analysis with XhoI and polymerase chain reaction targeting enterobacterial repetitive intergenic consensus sequences: can we predict the zoonotic potential of strains?

Campylobacter jejuni isolates of human, canine, feline, bovine and poultry origin were investigated for their genomic diversity using O-antigen typing (n = 271), SmaI (n = 158) and XhoI (n = 158) macrorestriction analysis and ERIC-PCR (n = 107). The O-antigens O:1/44, O:2, O:4 complex, O:37. O:40 were identified and 53.7% of the human and 56.1% of the animal strains were typable with the available antisera. Two ERIC-PCR pattern groups were generated representing human and animal strains as well as those exclusively of animal origin. XhoI macrorestriction analysis also distinguished 'human' and 'non-human' strain clusters, but by SmaI restriction mainly serotype-associated clusters were found. In conclusion, genomic differences may occur between 'human' and 'non-human' strains and this may reflect their potential to overcome the barrier from animals to humans.     

Production of high titer attenuated poliovirus strains on the serum-free PER.C6® cell culture platform for the generation of safe and affordable next generation IPV

BackgroundAs poliovirus eradication draws closer, alternative Inactivated Poliovirus Vaccines (IPV) are needed to overcome the risks associated with continued use of the Oral Poliovirus Vaccine and of neurovirulent strains used during manufacture of conventional (c) IPV. We have previously demonstrated the susceptibility of the PER.C6^® cell line to cIPV strains; here we investigated the suspension cell culture platform for growth of attenuated poliovirus strains.MethodsWe examined attenuated Sabin strain productivity on the PER.C6^® cell platform compared to the conventional Vero cell platform. The suitability of the suspension cell platform for propagation of rationally-attenuated poliovirus strains (stabilized Sabin type 3 S19 derivatives and genetically attenuated and stabilized MonoCre(X) strains), was also assessed. Yields were quantified by infectious titer determination and D-antigen ELISA using either serotype-specific polyclonal rabbit sera for Sabin strains or monoclonal cIPV-strain-specific antibodies for cIPV, S19 and MonoCre(X) strains.ResultsPER.C6^® cells supported the replication of Sabin strains to yields of infectious titers that were in the range of cIPV strains at 32.5 °C. Sabin strains achieved 30-fold higher yields (p < 0.0001) on the PER.C6^® cell platform as compared to the Vero cell platform in infectious titer and D-antigen content. Furthermore, Sabin strain productivity on the PER.C6^® cell platform was maintained at 10 l scale. Yields of infectious titers of S19 and MonoCre(X) strains were 0.5–1 log₁₀ lower than seen for cIPV strains, whereas D-antigen yield and productivities in doses/ml using rationally-attenuated strains were in line with yields reported for cIPV strains.ConclusionsSabin and rationally-attenuated polioviruses can be grown to high infectious titers and D-antigen yields. Sabin strain infection shows increased productivity on the PER.C6^® cell platform as compared to the conventional Vero cell platform. Novel cell platforms with the potential for higher yields could contribute to increased affordability of a next generation of IPV vaccines needed for achieving and maintaining poliovirus eradication.     

A colonisation-inhibition culture consisting of Salmonella Enteritidis and Typhimurium ΔhilAssrAfliG strains protects against infection by strains of both serotypes in broilers

Consumption of contaminated poultry meat is still an important cause of Salmonella infections in humans and there is a need for control methods that protect broilers from day-of-hatch until slaughter age against infection with Salmonella. Colonisation-inhibition, a concept in which a live Salmonella strain is orally administered to day-old chickens and protects against subsequent challenge, can potentially be used as control method. In this study, the efficacy of a Salmonella Typhimurium ΔhilAssrAfliG strain as a colonisation-inhibition strain for protection of broilers against Salmonella Typhimurium was evaluated. Administration of a Salmonella Typhimurium ΔhilAssrAfliG strain to day-old broiler chickens decreased faecal shedding and strongly reduced caecal and internal organ colonisation of a Salmonella Typhimurium challenge strain administered one day later using a seeder bird model. In addition, it was verified whether a colonisation-inhibition culture could be developed that protects against both Salmonella Enteritidis and Typhimurium. Therefore, the Salmonella Typhimurium ΔhilAssrAfliG strain was orally administered simultaneously with a Salmonella Enteritidis ΔhilAssrAfliG strain to day-old broiler chickens, which resulted in a decreased caecal and internal organ colonisation for both a Salmonella Enteritidis and a Salmonella Typhimurium challenge strain short after hatching, using a seeder bird model. The combined culture was not protective against Salmonella Paratyphi B varietas Java challenge, indicating serotype-specific protection mechanisms. The data suggest that colonisation-inhibition can potentially be used as a versatile control method to protect poultry against several Salmonella serotypes.     

BCG scar and positive tuberculin reaction associated with reduced child mortality in West Africa. A non-specific beneficial effect of BCG?

Previous studies have suggested that the bacille Calmette-Guérin (BCG) vaccine may have a non-specific beneficial effect on childhood survival in areas with high mortality. We examined whether BCG-vaccinated children with a BCG scar or a positive tuberculin reaction had better survival than children without such reactions. As part of an ongoing two-dose measles vaccine trial for which children were recruited at 6 months of age, we examined 1813 children for BCG scar at 6 months of age and 813 BCG-vaccinated children were skin-tested for delayed hypersensitivity to tuberculin, tetanus and diphtheria. We found that BCG-vaccinated children with a BCG scar had significantly lower mortality compared with BCG scar-negative children, the mortality ratio in the first 12 months of follow-up being 0.41 (0.25-0.67). BCG-vaccinated children with a positive tuberculin test had a mortality ratio of 0.45 (0.24-0.85) compared with tuberculin negative children. These results were unchanged by control for potential confounders or using different cut-off points for a tuberculin-positive response. Exclusion of dead children who had HIV antibodies did not modify the estimate (mortality rate (MR)=0.46 (0.23-0.94)). After censoring for tuberculosis (TB) exposure at home, the mortality ratios for having a scar and being tuberculin-positive were 0.46 (0.27-0.79) or 0.42 (0.21-0.84), respectively. Children positive to tetanus or diphtheria in the skin test had the same mortality as children not responding to these vaccine-related antigens. Thus, BCG scar and a positive tuberculin reaction were associated with better survival in early childhood in an area with high mortality. Since nothing similar was found for responders to diphtheria-tetanus-pertussis (DTP) vaccine, and the effect could not be explained by protection against tuberculosis, the effect of BCG vaccination could be due to non-specific immune-stimulation protecting against other infections.     

Surveillance of multidrug-resistant strains of Salmonella enterica serotype Typhimurium in southern Italy in the years 1992–1997

Spread of multidrug-resistant strains of Salmonella enterica serotype Typhimurium (S. typhimurium) is increasingly reported worldwide. The presence of a pattern of resistance to ampicillin, chloramphenicol, streptomycin, sulfonamides and tetracycline (ACSSuT), in some cases associated to trimethoprim and infrequently to quinolones, is of particular concern. This resistance pattern appears to be chromosomally encoded and, in most epidemiological studies, closely related to definitive type 104 (DT104).In southern Italy multidrug-resistant isolates of S. typhimurium had been identified since 1980, but only during 1992 S. typhimurium strains with chromosomally encoded drug resistance were first isolated from domestic animals.One hundred fifty-five isolates – 52.5% of the multidrug-resistant strains identified in the years 1992–1997 – were submitted to phage typing and plasmid profile analysis. Ribotyping was also performed in comparison with a random sample of 150 strains susceptible or resistant to three or less antibiotics identified in the same interval of time.Four ribotypes (RTs) -1, 5, 8, and 48 – included approximately 90% of the multiresistant strains, RT8 accounting for 61.2%. Phage type (PT) 193 is the most prevalent phage type.Phage typing and ribotyping suggest that few bacterial clones are involved in spread of multi- drug-resistant S. typhimurium strains in southern Italy.     

A multitude of strains add up to one big headache. Feeling the pressure?

A multitude of strains--most beyond the control of health care executives--are converging to create major headaches for hospitals and systems. Skyrocketing insurance premiums, surging drug spending, Medicaid cuts, a staffing crisis and huge hikes in liability insurance rates contribute to the unprecedented confluence of pressures. And there's more.     

How sharp is the short QuickDASH? A refined content and validity analysis of the short form of the disabilities of the shoulder, arm and hand questionnaire in the strata of symptoms and function and specific joint conditions

Purpose  

To assess and compare content, validity, and specificity of the QuickDASH (Disability of the arm, shoulder and hand questionnaire) as compared to the full-length DASH and other instruments to give a recommendation for its use depending on a specific clinical situation.     

Analysis of the cost-effectiveness of the implementation of Indoor Residual Spraying and distribution of Long-Lasting Insecticidal Nets in the municipality of Kouandé and municipality of Copargo in Benin

Background

In Benin, malaria was the leading cause of hospital consultation for children less than 5 years old (47.2%), and for all patients not hospitalized (42.3%). Its incidence among those who attended a health facility was respectively 42.9% and 17%. To address this problem, the National Program for the Fight against Malaria undertook, in 2011, a mass campaign of distribution of Long-Lasting Insecticidal Nets (LLINs). In addition to this strategy, the program decided to implement Indoor Residual Spraying in 7 of the 9 municipalities of Atacora department, which is one of the most malaria endemic areas. The objective of this study was to see if adding the IRS to the LLINs (municipality of Kouandé) strategy is cost-effective, as compared to the LLINs-only strategy (municipality of Copargo), in highly malaria endemic areas.

Method

This study was a cross-sectional study of the implementation of the IRS from June 2011 to July 2011. Regarding the selection of health workers, managers of the malaria program, and partners of implementation of the IRS, a reasoned choice was made. The data collection consisted mainly of a series of interviews with people responsible for resource management and the exploitation of documents provided by them.

Results

After the implementation of LLNs + IRS the annual incidence of malaria in health facilities decreased significantly at Kouandé-Centre and at Guilmaro. In the same period it increased significantly at Copargo- Centre, and decreased at Pabégou.The average cost per malaria case prevented (CE) was respectively 85,572.4 FCFA at Copargo Centre, 38,932.6 FCFA at Kouandé Centre, 15,940.6 FCFA at Pabégou and 174,728.5 FCFA at Guilmaro. According to the results, the CE ratio at Kouandé-Centre is lower than the CE ratio at Copargo- Centre and the CE ratio at Guilmaro is higher than the CE ratio at Pabégou.The LLINs?+?IRS strategy is more cost effective in urban areas than the LLINs-only strategy. The opposite result is observed in rural areas.

Conclusion

The LLINs?+?IRS strategy is cost effective in highly endemic areas both urban and rural, if communities sleep in sprayed structures and use LLINs even when it is hot.

     

Molecular typing and characterization of TEM,SHV, CTX-M,and CMY-2 β-lactamases in Enterobacter cloacae strains isolated in patients and their hospital environment in the west of Algeria

Objectives

Enterobacter cloacae is a major nosocomial bacterium causing severe infections. A multicenter retrospective cohort study was conducted to collect baseline information on the molecular characteristics of β-lactamase producing Enterobacter cloacae in the west of Algeria.

Materials and methods

We report a series of 42 extended-spectrum β-lactamase (ESBL) producing non-repetitive Enterobacter cloacae strains, collected in 3 university hospital (Tlemcen, Oran, and Sidi Bel Abbes). Antibiotic susceptibility testing (antibiogram and MIC) and screening for ESBL were performed according to the French Society for Microbiology guidelines. PFGE typing was used to characterize the clonality of all the strains. β-lactamase genes (bla_TEM, bla_SHV, bla_CTX-M, bla_ECB, and bla_CMY-2) were amplified by PCR with specific primers. Plasmid isolation, electroporation, and conjugation experiments were carried out using standard methods.

Results

Sequence analysis revealed that most strains produced CTX-M type ESBLs (CTX-M-15 and CTX-M-3), whereas only 5 produced SHV-type ESBLs (SHV-12). The bla_TEM gene was identified in all strains of Enterobacter cloacae. Several epidemic clones were determined. One strain was found to produce plasmid-mediated AmpC β-lactamase (CMY-2); this gene was transferred from E. cloacae by electroporation. Conjugation experiments showed that bla_CTX-M, bla_TEM, and bla_SHV were carried by conjugative plasmids of high molecular weight (≥ 70 kb).

Conclusion

The emergence of resistance genes is a public health problem.     

Characterization of phase I and phase II drug metabolism and the effect of Β-naphthoflavone in the liver and posterior kidney of the channel catfish,Ictalurs punctatus

Immature channel catfish (Ictalurus punctatus) were injected intraperitoneally with 50 mg/kg -naphthoflavone (BNF) and its effects on phase I and phase II xenobiotic metabolizing enzymes of liver and posterior kidney were evaluated. Microsomal monooxygenases in control animals exhibited higher specific activities in liver than in kidney although if data are expressed as turnover numbers, both organs have comparable activities, -naphthoflavone treatment resulted in increases in hepatic microsomal cytochrome P-450 content and ethoxyresorufin deethylase activity. Renal monooxygenases were not responsive to BNF injection. The phase II xenobiotic metabolizing systems of liver or kidney did not respond to BNF treatment. With the exception of epoxide hydrolase which was higher in renal microsomes, phase II drug metabolizing activity of liver cell fractions was about two-fold that observed in fractions isolated from posterior kidney.     

Organisation and financing of the health care systems of Bulgaria and Greece – what are the parallels?

Background  

The Bulgarian and Greek Medical Care systems have been reformated the last fifteen years. The aim of this study was an examination and comparison of the Bulgarian and Greek Medical Care Systems.