89 research outputs found
Capillary electrophoresis-atmospheric pressure chemical ionization-mass spectrometry using an orthogonal interface: Set-up and system parameters
Proteomics as a quality control tool of pharmaceutical probiotic bacterial lysate products
Probiotic bacteria have a wide range of applications in veterinary and human therapeutics. Inactivated probiotics are complex samples and quality control (QC) should measure as many molecular features as possible. Capillary electrophoresis coupled to mass spectrometry (CE/MS) has been used as a multidimensional and high throughput method for the identification and validation of biomarkers of disease in complex biological samples such as biofluids. In this study we evaluate the suitability of CE/MS to measure the consistency of different lots of the probiotic formulation Pro-Symbioflor which is a bacterial lysate of heat-inactivated Escherichia coli and Enterococcus faecalis. Over 5000 peptides were detected by CE/MS in 5 different lots of the bacterial lysate and in a sample of culture medium. 71 to 75% of the total peptide content was identical in all lots. This percentage increased to 87–89% when allowing the absence of a peptide in one of the 5 samples. These results, based on over 2000 peptides, suggest high similarity of the 5 different lots. Sequence analysis identified peptides of both E. coli and E. faecalis and peptides originating from the culture medium, thus confirming the presence of the strains in the formulation. Ontology analysis suggested that the majority of the peptides identified for E. coli originated from the cell membrane or the fimbrium, while peptides identified for E. faecalis were enriched for peptides originating from the cytoplasm. The bacterial lysate peptides as a whole are recognised as highly conserved molecular patterns by the innate immune system as microbe associated molecular pattern (MAMP). Sequence analysis also identified the presence of soybean, yeast and casein protein fragments that are part of the formulation of the culture medium. In conclusion CE/MS seems an appropriate QC tool to analyze complex biological products such as inactivated probiotic formulations and allows determining the similarity between lots
Cardiovascular drug use and differences in the incidence of cardiovascular mortality in elderly Seriban men
Objective:To assess whether the difference in risk of cardiovascular mortality between urban and rural areas of Serbia could be explained by differences in the use of cardiovascular medication. Methods: The Serbian cohorts of the Seven Countries Study, Velika Krsna (VK), Zrenjanin (ZR) and Belgrade (BG), were enrolled in 1962-1964 and were followed up for 25 years. The survivors of these cohorts were re-examined in 1987, 1988 and 1989, respectively. This second examination of elderly men aged 65 to 84 years included a questionnaire about current use of cardiovascular medication, risk factors and diseases and a physical examination. All subjects were followed until death or the predefined censor date (10 years after baseline). The Cox proportional hazards model was used to calculate the risk of cardiovascular mortality in the rural cohorts compared to the urban cohort and to adjust for confounding. Main outcome measure: Cardiovascular death. Results: A total of 227 men from VK, 184 men from ZR and 287 men from BG were followed for a mean duration of 7.4 years and was complete for all subjects. After exclusion of 13 subjects with missing medication data, the incidences of cardiovascular mortality in VK, ZR, and BG were 60, 74, and 26 per 1000 person-years, respectively. The prevalence of cardiovascular medication use was 38% in VK, 52% in ZR, and 59% in BG. The greatest difference in use of specific medication was observed for betablockers (0% in VK and ZR, 13% in BG). After adjustment for cardiovascular risk factors, diseases and age, the relative risks (RRs) of cardiovascular mortality were 2.12 [95% CI: 1.44Âż3.12], and 2.27 [95% CI: 1.56Âż3.30] in VK, and ZR compared to BG. Additional adjustment for the use of cardiovascular medication increased these RRs to 2.40 [95% CI: 1.61Âż3.60] and 2.55 [95% CI: 1.72Âż3.78], respectively. Conclusion:The variation in cardiovascular medication use could not explain the excess risk of mortality in the rural Serbian cohorts compared to urban Belgrade
A Functional Group Approach for Prediction of APPI Response of Organic Synthetic Targets
New approaches for capillary electrophoresis–mass spectrometry in drug analysis : Evaluation of photo-, chemical and thermospray ionization
During the past two decades, capillary electrophoresis–mass spectrometry (CE–MS) has emerged as a powerful analytical tool that is well suited to the analysis of pharmaceutical samples. CE–MS combines efficient and fast separation with mass-selective detection and can be considered as orthogonal to LC–MS. Until now, the coupling of CE with MS has predominantly been performed through electrospay ionization (ESI). However, conventional CE background electrolytes (BGEs) like phosphate and borate buffers may cause ion suppression in ESI, and thus lead to reduced or even complete loss of analyte signals. This especially hinders the application of special CE-modes such as micellar electrokinetic chromatography (MEKC) in which (nonvolatile) surfactants are added to enhance selectivity and/or to achieve separation of neutral compounds. In addition, ESI is less suited to analytes that are not readily ionized in solution. In this thesis, the design and performance of CE–MS systems based on alternative ionization techniques, viz. atmospheric pressure photoionization (APPI), atmospheric pressure chemical ionization (APCI) and theromospray ionization (TS), has been investigated. In both APCI and APPI, the sample is first vaporized after which ionization is initiated by a corona discharge or VUV irradiation, respectively. Under specific conditions, polar compounds could be detected in the absence of corona discharge or VUV-photons. In this case, ion formation largely appeared to occur through TS. APPI and APCI were both found suitable for ionization of neutral compounds that were poorly detected by electrospray ionization. APPI enabled the formation of odd-electron ions, and therefore provided a means to detect apolar compounds upon separation by MEKC. The gas-phase-ion formation of ionic species, such as quaternary ammonium compounds, does not rely on charge-exchange or proton-transfer and can therefore not be analysed by APCI-MS or APPI-MS. Instead, this type of compounds may be analysed by TS-MS, which can be carried out using either an APPI or APCI source. Furthermore, under specific conditions, APPI and TS can be employed simultaneously, which ensures the applicability of CE–APPI-MS for a wide variety of compounds ranging from ionic to apolar. With ESI and TS analyte signals were significantly suppressed in the presence of nonvolatile buffers or surfactants. By contrast, APCI and APPI showed a strong compatibility with these constituents. With all CE–MS systems, impurities in drugs down to 0.1% (w/w) could be detected and identified. Overall, ESI and TS appeared the most efficient ionization techniques, especially for impurities that are charged in solution, resulting in detection limits down to 100 ng/mL in the full-scan mode. The signal response for APCI and APPI was often lower than for ESI, but still enabled detection at the 0.1% level by injection of 1 mg/mL of the parent compound. These results show that APPI, APCI and TS are suitable ionization techniques for drug impurity profiling by CE–MS. The availability of alternative ionization methods for CE–MS enhances the compatibility of this technique with nonvolatile buffers and surfactants, and allows a larger number of impurities in drugs to be detected
M'dankaka nawe
An adaptation of the previous item TR098-07 accompanied by a guitar. The singer sings a slightly different version to his guitar. Konsolo dance song with guitar
[Fotografie della Somalia: Danze Mingis]
Fotografie appartenenti alla collezione privata del Prof. Francesco Giannattasio._-_Sawirro ka mid ah macluumaad uu prof. Francesco Giannattasio soo ururiyay Soomaaliya._-_Pictures belonging to Francesco Giannattasio’s private collection
GGZ dicht bij de burger. Laagdrempelige zorg als het kan en specialistische zorg als het nodig is
GeĂŻntegreerde zorg en re-integratie voor werkenden en uitkeringsgerechtigden met psychische klachten : verkenning naar knelpunten en oplossingen
Verkennend onderzoek naar de mogelijkheden om zorg en werk wat betreft kwaliteit, toegankelijkheid en financiering meer op elkaar af te stemmen voor mensen met psychische klachten. De verkenning bestaat uit twee delen. In het eerste deel worden de bestaande knelpunten geïnventariseerd waar het gaat om de afstemming zorg en werk voor werkenden en uitkeringsgerechtigden met veel voorkomende psychische klachten (Common Mental Disorders). Dit deel is gebaseerd zeven ervaringsverhalen van cliënten en een institutionele stakeholderanalyse. In het tweede deel wordt ingegaan op mogelijke oplossingsrichtingen
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