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A total of 1712 strains of Haemophilus influenzae isolated from patients with invasive diseases were obtained from ten Brazilian states from 1996 to 2000. ß-Lactamase production was assessed and the minimum inhibitory concentrations (MIC) of ampicillin, chloramphenicol, ceftriaxone and rifampin were determined using a method for broth microdilution of Haemophilus test medium. The prevalence of strains producing ß-lactamase ranged from 6.6 to 57.7%, with an overall prevalence of 18.4%. High frequency of ß-lactamase-mediated ampicillin resistance was observed in Distrito Federal (25%), São Paulo (21.7%) and Paraná (18.5%). Of the 1712 strains analyzed, none was ß-lactamase negative, ampicillin resistant. A total of 16.8% of the strains were resistant to chloramphenicol, and 13.8% of these also presented resistance to ampicillin, and only 3.0% were resistant to chloramphenicol alone. All strains were susceptible to ceftriaxone and rifampin and the MIC90 were 0.015 µg/ml and 0.25 µg/ml, respectively. Ceftriaxone is the drug of choice for empirical treatment of bacterial meningitis in pediatric patients who have not been screened for drug susceptibility. The emergence of drug resistance is a serious challenge for the management of invasive H. influenzae disease, which emphasizes the fundamental role of laboratory-based surveillance for antimicrobial resistance.

Results of experiments and modeling of a compact (800 cm3) membrane reformer module for the production of 0.25–0.30 Nm3/h hydrogen by methane steam reforming are reported. The module consists of a two-sided composite membrane disc with a 50 μm PdAg layer and two adjacent 4 mm thick Ni foam discs (60 ppi). A nickel catalyst and a porous support were deposited on the foam discs to give the final composition of 10%Ni/10%MgO/Ni-foam. Membrane permeability by pure hydrogen was investigated, and coefficients of transverse hydrogen transport across the Ni foam to the membrane in the case of inlet binary N2H2 mixture were refined in order to account for concentration polarization effect into the model. Activity of the catalytic discs was measured in a differential laboratory scale reactor at a pressure of 1 bar and temperature of 400–600 °C. Modules were tested at a 8–13 bar pressure of the mixture in the reforming zone and at 1 bar of pure hydrogen under the membrane, H2O/C = 2.5–3 and a module temperature of 550–680 °C (with and without hydrogen removal). Two modifications of the module were tested: consecutive (I-type) and parallel (II-type) flow of the reaction mixture around two sides of the membrane disc. In order to optimize construction of the module, calculations were made for revealing the effect of thickness of the PdAg membrane layer (5–50 μm), thickness of the Ni foam discs (0.5–8 mm) and temperature (600–700 °C) on the hydrogen output of the module. A comparison of the values obtained in our experiments (>1 MW/m3 and >0.7 kg(H2)/h/m2) with the literature data reported by other authors showed that the developed modules are promising for practical application as components of a fuel processor section for mobile applications. [ABSTRACT FROM AUTHOR]

Hundreds of thousands of individuals who experience lasting sequelae after sepsis and infections in Germany do not receive optimal care. In this White Paper we present measures for improvement, which were developed by a multidisciplinary expect panel as part of the SEPFROK project. Improved care rests on four pillars: 1. cross-sectoral assessment of sequelae and a structured discharge and transition management, 2. interdisciplinary rehabilitation and aftercare with structural support, 3. strengthening the specific health literacy of patients and families, and 4. increased research into causes, prevention and treatment of sequelae. To achieve this, appropriate cross-sectoral care structures and legal frameworks must be created., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

We detected delayed and reduced antibody and T-cell responses after BNT162b2 vaccination in 71 elderly persons (median age 81 years) compared with 123 healthcare workers (median age 34 years) in Germany. These data emphasize that nonpharmaceutical interventions for coronavirus disease remain crucial and that additional immunizations for the elderly might become necessary.

Patients with kidney failure have notoriously weak responses to common vaccines. Thus, immunogenicity of novel SARS-CoV-2 vaccines might be impaired in this group. To determine immunogenicity of SARS-CoV-2 vaccination in patients with chronic dialysis, we analyzed the humoral and T-cell response after two doses of mRNA vaccine Tozinameran (BNT162b2 BioNTech/Pfizer). This observational study included 43 patients on dialysis before vaccination with two doses of Tozinameran 21 days apart. Overall, 36 patients completed the observation period until three weeks after the second dose and 32 patients were further analyzed at week 10. Serum samples were analyzed by SARS-CoV-2 specific IgG and IgA antibodies ~1, ~3-4 and ~10 weeks after the second vaccination. In addition, SARS-CoV-2-specific T-cell responses were assessed at ~3-4 weeks by an interferon-gamma release assay (IGRA). Antibody and T cell outcomes at this timepoint were compared to a group of 44 elderly patients not on dialysis, after immunization with Tozinameran. Median age of patients on chronic dialysis was 74.0 years (IQR 66.0, 82.0). The proportion of males was higher (69.4%) than females. Only 20/36 patients (55.6%, 95%CI: 38.29-71.67) developed SARS-CoV-2-IgG antibodies at the first sampling, whereas 32/36 patients (88.9%, 95%CI: 73.00-96.38) demonstrated IgG detection at the second sampling. In a longitudinal follow-up at ~10 weeks after the second dose, the proportion of dialysis patients reactive for anti-SARS-CoV-2-IgG decreased to 27/32 (84.37%, 95%CI: 66.46-94.10) The proportion of anti-SARS-CoV-2 S1 IgA decreased from 33/36 (91.67%; 95%CI: 76.41-97.82) at weeks 3-4 down to 19/32 (59.38; 95%CI: 40.79-75.78). Compared to a cohort of vaccinees with similar age but not on chronic dialysis seroconversion rates and antibody titers were significantly lower. SARS-CoV-2-specific T-cell responses 3 weeks after second vaccination were detected in 21/31 vaccinated dialysis patients (67.7%, 95%CI: 48.53-82.68) compared to 42/44 (93.3%, 95%CI: 76.49-98.84) in controls of similar age. Patients on dialysis demonstrate a delayed, but robust immune response three to four weeks after the second dose, which indicates effective vaccination of this vulnerable group. However, the lower immunogenicity of Tozinameran in these patients needs further attention to develop potential countermeasures such as an additional booster vaccination., Competing Interests: KK is partly contractually provided to Labor Berlin-Charité Vivantes GmbH. VC is named together with Euroimmun GmbH on a patent application filed recently regarding the diagnostic of SARS-CoV-2 by antibody testing. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Schrezenmeier, Bergfeld, Hillus, Lippert, Weber, Tober-Lau, Landgraf, Schwarz, Kappert, Stefanski, Sattler, Kotsch, Dörner, Sander, Budde, Halleck, Kurth, Corman and Choi.)

Complexins (Cplxs) regulate the speed and Ca(2+)-sensitivity of synaptic vesicle fusion. It has been shown that all four known Cplxs are present at mouse retinal synapses--at conventional amacrine cell synapses (Cplx 1 to Cplx 3) and at photoreceptor and bipolar cell ribbon synapses (Cplx 3 and Cplx 4) [K. Reim et al. (2005) J. Cell Biol., 169, 669-680]. Electroretinographic recordings in Cplx 3/Cplx 4 double-knockout (DKO) mice showed perturbed transmission in the outer plexiform layer, and possible changes in the inner plexiform layer [K. Reim et al. (2009) J. Cell Sci., 122, 1352-1361]. In the present study, we examined the effects of the absence of Cplx 3 and Cplx 4 on ganglion cell responses. We report that the lack of Cplx 3 and Cplx 4 differentially impacts the ON and OFF pathways. Under photopic conditions, the responses in the cone OFF pathway are largely unaffected, whereas the responses in the cone ON pathway are diminished in Cplx 3/Cplx 4 DKO mice. Under scotopic conditions, both ON and OFF response rates are reduced and high-sensitivity OFF responses are missing in Cplx 3/Cplx 4 DKO mice. The electrophysiological findings are corroborated by new immunocytochemical findings. We now show that rod spherules contain only Cplx 4. However, both Cplx 3 and Cplx 4 co-localize in cone pedicles. In the inner plexiform layer, Cplx 3 is present in rod bipolar cell terminals and in amacrine cell processes. Most importantly, Cplx 3 is localized in the lobular appendages of AII amacrine cells, the sites of signal transmission from the primary rod pathway into the OFF pathway in the inner plexiform layer., (© 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.)

Cerebrospinal fluid (CSF) samples from 210 patients (200 with clinical evidence of bacterial meningitis, 10 with other clinical neurologic disease) were tested by a Dot-ELISA assay for detection of polysaccharide antigen of N. meningitidis group C. CSF samples were treated with EDTA 0.1 M, at pH 7.5 and heated to 90>C for 10 min. Polyclonal antiserum was purified by use of ethanol fractionation. The results were compared to those using bacterial culture (BC), latex agglutination (LA), counterimmunoelectrophoresis (CIE), and direct microscopy (DM) methods. Test results showed a correlation of 93.3%, 94.3%, 91.0% and 69.5% respectively, and sensitivity of 0.947 and specificity of 0.930. This study suggests that the dot-ELISA assay of CSF is a useful alternative technique for the diagnosis of group C meningitis.

From 1989 to 1995, a total of 391 Haemophilus influenzae isolates were recovered from the cerebrospinal fluid (CSF) of hospitalized patients in São Paulo, Brazil. The majority of strains were isolated from infants aged less than 5 years. Strains belonging to biotype I (64.7%), biotype II (34.5%) and biotype IV (0.76%) were detected. Ninety-nine percent of these strains were serotype b. Minimal inhibitory concentration (MIC) was determined for ampicillin, chloramphenicol and ceftriaxone. The ss-lactamase assay was performed for all strains. The rate of ss-lactamase producer strains ranged from 10 to 21.4% during a period of 7 years, with an overall rate of 13.8%. Of the 391 strains analyzed, none was ss-lactamase negative ampicillin resistant (BLNAR). A total of 9.7% of strains showed resistance to both ampicillin and chloramphenicol; however, 4% of them were resistant to ampicillin only and 2% to chloramphenicol. All strains were susceptible to ceftriaxone and the MIC90 was 0.007 microg/ml, suggesting that ceftriaxone could be an option for the treatment of bacterial meningitis in pediatric patients who have not been screened for drug sensitivity.

Infection with Neisseria meningitidis group B has been difficult to detect, partly because this bacterial group's polysaccharide is a weak immunogen. This article describes work carried out to test a new procedure (MB-Dot-ELISA) employing a high-titered horse antiserum for detection of N. meningitidis group B antigens. The study assayed cerebrospinal fluid samples from 585 subjects, 574 with suspected meningitis cases and 11 with neurologic disorders. The results of the assay indicated a sensitivity of 0.991 and a specificity of 0.826. These results were superior to those obtained with latex agglutination and in substantial agreement with the results of counterimmunoelectrophoresis and bacteriologic methods. Overall, the MB-Dot-ELISA was found to be sensitive, inexpensive, and suitable for public health laboratory investigations.

Infection with Neisseria meningitidis group B has been difficult to detect, partly because this bacterial group's polysaccharide is a weak immunogen. This article describes work carried out to test a new procedure (MB-Dot-ELISA) employing a high-titered horse antiserum for detection of N. meningitidis group B antigens. The study assayed cerebrospinal fluid samples from 585 subjects, 574 with suspected meningitis cases and 11 with neurologic disorders. The results of the assay indicated a sensitivity of 0.991 and a specificity of 0.826. These results were superior to those obtained with latex agglutination and in substantial agreement with the results of counterimmunoelectrophoresis and bacteriologic methods. Overall, the MB-Dot-ELISA was found to be sensitive, inexpensive, and suitable for public health laboratory investigations.

We compare the results obtained by counterimmunoelectrophoresis in samples of serum and cerebrospinal fluid with microbiologic methods for 3,298 patients suspected of bacterial meningitis and/or septicemia at Instituto Adolfo Lutz, São Paulo, in a retrospective study of the period from July 1998 to July 1994. Of the 415 patients (12.6% of the total cases studied) who were positive by the serum test, only 249 (7.6% of the total cases studied) were also positive when cerebrospinal fluid was assayed. Thus, 40% of the positives (5.6% of the total) were identifiable by analysis of serum but not of cerebrospinal fluid. Neisseria meningitidis accounted for 77.7% (129) and Haemophilus influenzae for 22.3% (37) of the positive results obtained only when serum was examined. These data show that although sensitivity and specificity of serum counterimmunoelectrophoresis are relatively low compared to cerebrospinal fluid counterimmunoelectrophoresis, the serum test is necessary to complement cerebrospinal fluid counterimmunoelectrophoresis data.

Eighty purulent cerebrospinal fluid (CSF) samples from patients with clinical evidence of meningitis were studied using the Directigen latex agglutination (LA) kit to determine the presence of bacterial antigen in CSF. The results showed a better diagnostic performance of the LA test than bacterioscopy by Gram stain, culture and counterimmunoelectrophoresis (CIE), as far as Neisseria meningitidis groups B and C, and Haemophilus influenzae type b are concerned, and a better performance than bacterioscopy and culture considering Streptococcus pneumoniae. Comparison of the results with those of culture showed that the LA test had the highest sensitivity for the Neisseria meningitidis group C. Comparing the results with those of CIE, the highest levels of sensitivity were detected for N. meningitidis groups B and C. Regarding specificity, fair values were obtained for all organisms tested. The degree of K agreement when the LA test was compared with CIE exhibited better K indices of agreement for N. meningitidis groups B and C.

Cerebrospinal fluid (CSF) samples from 2083 patients with acquired immunodeficiency syndrome (AIDS) and neurological complications were bacteriologically examined during a period of 7 years (1984-1990). The percentage of patients who had at least one bacterial agent cultured from the CSF was 6.2%. Mycobacterium tuberculosis was the most frequently isolated agent (4.3%), followed by Mycobacterium avium complex or MAC (0.7%), Pseudomonas spp (0.5%), Enterobacter spp (0.4%), and Staphylococcus aureus (0.3%). Among 130 culture positive patients, 89 (68.5%) had M. tuberculosis and 15 (11.6%) had MAC. The frequency of bacterial isolations increased from 1988 (5.2%) to 1990 (7.2%), partly due to the increase in MAC isolations. Bacterial agents were more frequently isolated from patients in the age group 21-30 years and from women (p < 0.05).

The history of the discovery of vitamins was initiated by the observation that beriberi is caused by qualitatively poor nutrition rather than by microorganisms. An early theory suggested the formation of toxins by improper cooking, preservation, or storage; however, research soon took another turn. Feeding experiments with standardized food pointed at the existence of 'accessory factors', present in food in small amounts. These factors seemed to be essential for the maintenance of metabolic processes, yet could not be synthesized by the organism. This was the initial spark for a worldwide research boom. The period from 1912 to 1948 saw the isolation and identification of individual factors belonging to a variety of chemical classes collectively labeled as 'vitamins'.

Unlike Neisseria meningitidis groups A, C, Y and W135, the group B capsular polysaccharide has been shown to be chemically and immunologically identical to the capsular polysaccharide of Escherichia coli K1. Both components are sialic acid homopolymers and are poorly immunogenic. Nevertheless, due to the high incidence of Neisseria meningitidis group B meningitis in the population of the State of São Paulo, preparing antiserum to this serogroup for diagnostic purposes has become a matter of high priority. Of the many immunization schemes proposed, intravenous inoculation of whole bacteria previously inactivated with formaldehyde and simultaneous intradermal inoculation with a mixture of the bacterial polysaccharide fraction and whole bacteria in complete Freund;s adjuvant have produced the best results. The antiserum was treated with immunoadsorbents prepared with aluminum chloride and protein and/or polysaccharide antigens from each of the following heterologous bacteria: Haemophilus influenzae type b, Streptococcus pneumoniae, Escherichia coli other than K1, and Staphylococcus aureus, in order to eliminate cross-reactivity. For quality control analysis, the antiserum was assessed by the immunodiffusion, counterimmunoelectrophoresis, dot-ELISA, and immuno-blot techniques against homologous antigens. Specificity was obtained after treating the antiserum with Haemophilus influenzae type b polysaccharide immunosorbent.

Serogroup B Neisseria meningitidis is the most common cause of epidemic meningococcal disease in developed countries. Until recently no vaccine has been available for prevention of infection with this organism. In an attempt to control epidemic serogroup B meningococcal disease in greater Sao Paulo, Brazil, during 1989 and 1990, a Cuban-produced outer-membrane-protein-based serogroup B meningococcal vaccine was given to about 2.4 million children aged from 3 months to 6 years. We have done a case-control study to estimate the efficacy of the vaccine in greater Sao Paulo. Microbiologically confirmed cases of serogroup B meningococcal disease were identified through hospital-based surveillance. Controls were matched by neighbourhood and age. Vaccination status was confirmed by inspection of vaccination cards. Between June, 1990, and June, 1991, 112 patients and 409 matched controls with confirmed vaccine status were enrolled. Estimated vaccine efficacy varied by age: 48 months or older = 74% (95% Cl 16 to 92%), 24 to 47 months = 47% (-72 to 84%), and less than 24 months = -37% (< -100 to 73%). Our results suggest that the Cuban-produced vaccine may be effective for prevention of serogroup B meningococcal disease in older children and adults.

Since 1977, the Instituto Adolfo Lutz (IAL) is having interest in the serotyping of S. pneumoniae or pneumococcus from infections caused by this bacteria. The isolated strains have been sent to the WHO Pneumococcal Reference Center, Pennsylvania, U.S.A.. From 1977 to 1988, 1.000 pneumococcus strains isolated from cerebrospinal fluid were typed, according to Danish nomenclature, and 60 serotypes were identified. The most frequent serotypes were 1, 6B, 18C, 14, 5, 3, 6A, 23F, 19F, and 38. Among different age groups, they showed a variable incidence, with serotype 6B in the ages of zero to almost 2 years old, serotype 1 in the age group of 2 to 50 years old, and serotype 3 in the ages over 50. During the 12 years study, 25 serotypes showed some uniformity in the frequency, the same as with the seasonal fluctuations. Concerning the severity of the pneumococcal infections, chiefly meningitis, and the few information related to pneumococcus serotypes which occur in the area, it was considered of high relevance to have the information of serotypes, once polysaccharide vaccines have been employed with success to prevent these infections.

Strains of H. aegyptius isolated during outbreak of Brazilian Purpuric Fever (BPF) in Brazil were characterized antigenically by slide agglutination test utilizing antiserum produced with a H. aegyptius strain isolated from blood culture from a patient with BPF. By means of this method, it were identified H. aegyptius strains responsible for outbreaks of conjunctivitis with identical antigenic characteristics to strains isolated from BPF. The sensitivity and specificity of slide seroagglutination test was 97.7% and 89.6% respectively; therefore this assay was efficient to be used as a screening method in the studies of purulent conjunctivitis for detecting high risk populations for BPF, and to implement measures that will increase the efficiency of epidemiologic surveillance.