Characterization of monoclonal antibodies for rapid identification of Actinomyces naeslundii in clinical samples

The purpose of this study was to generate highly specific serological reagents for the quantitative identification of Actinomyces naeslundii in clinical samples, in particular dental plaque. Balb/c mice were immunized with pasteurized human A. naeslundii strains representing different genospecies and serotypes. Ten hybrid cell lines secreting monoclonal antibodies reactive with A. naeslundii were isolated and characterized. Antibody specificity was determined by indirect immunofluorescence and enzyme-linked immunosorbent assay using strains from 59 species and by immunofluorescence analyses of supragingival plaque from 10 gingivitis patients. Nine monoclonal antibodies reacted selectively with A. naeslundii, whereas one additionally bound to Actinomyces israelii. They recognized at least nine different epitopes with characteristic expression patterns among the test strains. Six clusters of antigenically unique or closely related strains could be distinguished. Clusters 1, 4, and 5 represented by 12, 18, and 5 strains, respectively, comprised over 80% of the A. naeslundii strains tested. All reference strains for genospecies 1 grouped with cluster 1. Strains associated with genospecies 2 fell into clusters 4 and 5. Tests with mutant strains indicated that three monoclonal antibodies recognize type 2 and one type 1 fimbriae of genospecies 2. Only four isolates grouped with clusters 2 and 3 characterized by the expression of cluster-specific antigens. Interestingly, cluster 2 and 3 bacteria were markedly more abundant in vivo than indicated by their sparse representation in our strain collection. Overall, all but one of the new monoclonal antibodies should prove of value for the serological classification and rapid quantitative determination of A. naeslundii in clinical sample

Dual Transoral Endoscopic Resection of a Symptomatic Giant Brunneroma

Brunneroma is a rare, benign, proliferative lesion arising from the Brunner's glands of the duodenum that exceptionally may evolve towards a malignant transformation, usually discovered incidentally at endoscopy. Occasionally, these lesions manifest as a rare cause of duodenal obstruction or upper gastrointestinal bleeding and require resection, usually for tumors larger than 4 cm. The special aspect of our case is the technically difficult but successful dual transoral endoscopic resection of a giant (6.5 × 4 × 2.4 cm) brunneroma with a very thick and long peduncle located extremely close to the pylorus, highlighting the possibilities of endosurgery. Distal stomach resection with Roux-en-Y reconstruction as an alternative would have caused higher morbidity and costs

Advancement of the 10-species subgingival Zurich Biofilm model by examining different nutritional conditions and defining the structure of the in vitro biofilms

BACKGROUND: Periodontitis is caused by a highly complex consortium of bacteria that establishes as biofilms in subgingival pockets. It is a disease that occurs worldwide and its consequences are a major health concern. Investigations in situ are not possible and the bacterial community varies greatly between patients and even within different loci. Due to the high complexity of the consortium and the availability of samples, a clear definition of the pathogenic bacteria and their mechanisms of pathogenicity are still not available. In the current study we addressed the need of a defined model system by advancing our previously described subgingival biofilm model towards a bacterial composition that reflects the one observed in diseased sites of patients and analysed the structure of these biofilms. RESULTS: We further developed the growth media by systematic variation of key components resulting in improved stability and the firm establishment of spirochetes in the 10-species subgingival Zurich biofilm model. A high concentration of heat-inactivated human serum allowed the best proliferation of the used species. Therefore we further investigated these biofilms by analysing their structure by confocal laser scanning microscopy following fluorescence in situ hybridisation. The species showed mutual interactions as expected from other studies. The abundances of all organisms present in this model were determined by microscopic counting following species-specific identification by both fluorescence in situ hybridisation and immunofluorescence. The newly integrated treponemes were the most abundant organisms. CONCLUSIONS: The use of 50% of heat-inactivated human serum used in the improved growth medium resulted in significantly thicker and more stable biofilms, and the quantitative representation of the used species represents the in vivo community of periodontitis patients much closer than in biofilms grown in the two media with less or no human serum. The appearance of T. denticola, P. gingivalis, and T. forsythia in the top layer of the biofilms, and the high abundance of T. denticola, reflects well the microbial situation observed at diseased sites. The improved model biofilms will allow further investigations of interactions between individual species and of the effects of atmospheric or nutritional changes, as well as interactions with tissue cells

Evidence for the Necessity to Systematically Assess Micronutrient Status Prior to Bariatric Surgery

Background: Bariatric surgery has been proven the most effective treatment of morbid obesity, but micronutrient deficiency following bariatric surgery is a major concern. Increasing evidence points to a generally poor micronutrient status in obese subjects. Methods: We assessed micronutrient status in 232 morbidly obese subjects (BMI ≥ 35kg/m2) prior to bariatric surgery. Serum albumin, calcium, phosphate, magnesium, ferritin, hemoglobin, zinc, folate, vitamin B12, 25-OH vitamin D3, and intact parathormone (iPTH) were determined. In a sub-sample of 89 subjects, we additionally assessed copper, selenium, vitamin B1, B3, B6, A, and E levels. Results: Deficiencies were found in 12.5% of the subjects for albumin, 8.0% for phosphate, 4.7% for magnesium, 6.9% for ferritin, 6.9% for hemoglobin, 24.6% for zinc, 3.4% for folate, and 18.1% for vitamin B12. In addition, 25.4% showed a severe 25-OH vitamin D3 deficiency, which was accompanied by a secondary hyperparathyroidism in 36.6% cases. Prevalence of albumin deficiency (p < 0.007) and of anemia (p < 0.003; in women only) significantly increased with BMI. Of note, 48.7% of the subjects showed at least one of the most prevalent deficiencies, i.e., vitamin B12, zinc and severe 25-OH vitamin D3 deficiency. In the sub-sample, 32.6% showed a selenium, 5.6% a vitamin B3, 2.2% a vitamin B6, and 2.2% a vitamin E deficiency. Copper, vitamin B1, and vitamin A deficiency was found in none of the subjects. Conclusion: Data indicate a high prevalence of micronutrient deficiencies in morbidly obese subjects. Based on these results, we strongly recommend a systematic assessment of the micronutrient status in all candidates for bariatric surger

A Novel Distal Very Long Roux-en Y Gastric Bypass (DVLRYGB) as a Primary Bariatric Procedure—Complication Rates, Weight Loss, and Nutritional/Metabolic Changes in the First 355 Patients

Proximal Roux-en Y gastric bypass (RYGB) representing the most frequently performed bariatric procedure yields a weight loss failure rate of around 20%. In order to reduce failure rates, we established a novel distal RYGB variant characterized by a very long alimentary (Roux) limb and a short common channel. Up to 5years, follow-up data (complication rates, weight loss, nutritional/metabolic changes) of the first 355 patients (mean ± SD preoperative age, 41.4 ± 10.8years; BMI, 48.5 ± 11.5kg/m2) who underwent the novel Distal Very Long Roux-en Y Gastric Bypass (DVLRYGB) were analysed. Overall follow-up rate was 98.9%, mean follow-up time 1.6 ± 1.4years. Limb lengths were as follows: common channel 76 ± 7cm, biliopancreatic limb 79 ± 14cm, and alimentary (Roux) limb 604 ± 99cm. The operation was performed laparoscopically in 95.2% of the cases. Thirty-day mortality was zero; major and minor complication rate was 4.5% and 10.4%, respectively. Average excess weight loss (EWL) was >74% 3, 4, and 5years after the operation and failure rate defined by an EWL < 50% remained < 6%. Annually blood measurements revealed a relatively low incidence rate of severe nutritional deficiencies, but mild anaemia and hypoproteinemia were frequently observed. Laparoscopic revision with a proximalization of the lower anastomosis was required in 4 (1.1%) patients. Data indicate that our DVLRYGB leads to excellent weight loss results. Furthermore, within the setting of a structured multidisciplinary follow-up program, the incidence of severe malnutrition states was relatively lo

Differential Changes in Dietary Habits after Gastric Bypass Versus Gastric Banding Operations

Background: Reduction of food intake is an important mechanism by which bariatric procedures reduce body weight. However, only few studies have systematically assessed what patients actually eat after different types of bariatric operations. Methods: Dietary habits were assessed by a food frequency questionnaire in 121 bariatric patients (48 gastric bypass patients, 73 gastric banding patients) during follow-up visits in our interdisciplinary obesity center as well as in 45 severely obese (body mass index (BMI) > 35kg/m2) and 45 nonobese (BMI < 27kg/m2) control subjects. Results: As compared with nonobese control subjects, obese control subjects consumed more meat, white bread, and diet soft drinks. Gastric bypass patients showed an enhanced consumption of foods rich in protein such as poultry, fish, and eggs as well as of cooked vegetables, while the consumption of fatty sweets like chocolate, cake, biscuits, and cookies was found to be distinctly reduced in this patient group. In contrast, gastric banding patients reported on a reduced intake of pasta, white bread, and fresh fruits and, just like gastric bypass patients, also on an enhanced intake of poultry and fish. Direct comparison of dietary habits between the two bariatric patient groups revealed that gastric bypass patients consumed more frequently fresh fruits, eggs, and diet soft drinks but strikingly less chocolate than gastric banding patients. Conclusion: Collectively, data clearly point to distinct changes in dietary habits after bariatric operations which markedly differ between gastric bypass and gastric banding patients. Overall, it is tempting to conclude that gastric bypass operations lead to a healthier and a more balanced diet than gastric band implantation

Biofilm Matrixome: Extracellular Components in Structured Microbial Communities

Biofilms consist of microbial communities embedded in a 3D extracellular matrix. The matrix is composed of a complex array of extracellular polymeric substances (EPS) that contribute to the unique attributes of biofilm lifestyle and virulence. This ensemble of chemically and functionally diverse biomolecules is termed the 'matrixome'. The composition and mechanisms of EPS matrix formation, and its role in biofilm biology, function, and microenvironment are being revealed. This perspective article highlights recent advances about the multifaceted role of the 'matrixome' in the development, physical-chemical properties, and virulence of biofilms. We emphasize that targeting biofilm-specific conditions such as the matrixome could lead to precise and effective antibiofilm approaches. We also discuss the limited knowledge in the context of polymicrobial biofilms, and the need for more in-depth analyses of the EPS matrix in mixed communities that are associated with many human infectious diseases. Keywords: extracellular matrix; extracellular polymeric substances (EPSs); microenvironments; polymicrobial biofilm; spatial organization; virulence

Bewertung des ZPO-Revisionsentwurfs zum kollektiven Rechtsschutz : eine Untersuchung anhand eines Rechtsvergleichs mit den Vorschriften der EU und deren Mitgliedstaaten

In der Schweizer Gesetzgebung existiert aktuell kein Instrument, welches eine effektive Durchsetzung von Massen- und Streuschäden gewährleistet. Mit der Botschaft zur Änderung der Schweizerischen Zivilprozessordnung vom 10. Dezember 2021 soll der kollektive Rechtsschutz durch Einführung des Instituts der Sammelklage nun gestärkt werden. Allerdings wird die Annahme der Revision vorerst aufgeschoben aufgrund Unstimmigkeiten im Parlament. In der Europäischen Union hingegen verfügen einige Mitgliedstaaten bereits seit mehreren Jahren über eine Sammelklage. Zudem hat die Europäische Union im Jahr 2020 eine Richtlinie erlassen, wonach nun alle Mitgliedstaaten eines der Sammelklage entsprechendes Instrument einzuführen haben. Der Zweck der Arbeit ist es, die Stärken und Schwächen der Sammelklage in der Europäischen Union zu identifizieren und die Schweizer Bestimmungen des Revisionsentwurfs sodann mittels eines Rechtsvergleichs zu bewerten. Anhand der Bewertung sollen allfällige Risiken erkannt und folgend Empfehlungen abgegeben werden, wie diese entsprechend minimiert werden können. Zur Beantwortung der Fragestellung werden die relevanten Gesetzesbestimmungen sowie deren Materialen und Gerichtsurteile als Primärquellen analysiert und mit Expertenmeinungen aus der Literatur ergänzt. Die Bestimmungen der Europäischen Union und der Schweiz werden einander sodann anhand eines Rechtsvergleichs gegenübergestellt. Die Analyse der europäischen Vorschriften zeigt, dass ein ausgiebiger Missbrauchsschutz gewährleistet ist, aber als Schwächen insbesondere die Gefahren des Forum Shoppings, einer erhöhten Rechtsunsicherheit für betroffene Personen durch eine Vielzahl laufender Verfahren sowie des vermehrten Versuchs, politische Ziele auf dem gerichtlichen Weg durchzusetzen, drohen. Aufgrund des Rechtsvergleichs ist bei den Schweizer Bestimmungen sodann als positiv zu bewerten, dass durch die Sammelklage die Ziele eines effektiven kollektiven Rechtsschutzes erreicht werden können und auch sie einen umfangreichen Missbrauchsschutz bieten. Als negativ zu bewerten sind indessen der Verzicht auf eine Einschränkung der Möglichkeit der Drittfinanzierung und des Forum Shoppings sowie der Verzicht auf die Einführung eines schweizweiten Registers zur Koordination der Sammelklagen. Um diese Schwächen zu minimieren, ist es zu empfehlen, die Bestimmungen des ZPO-Revisionsentwurfs anzupassen, indem die Drittfinanzierung einer Klage durch eine maximale Finanzierungsquote beschränkt wird und dem Forum Shopping durch gezieltere Zuständigkeitsregelungen entgegengewirkt wird. Zudem erscheint es zweckmässig, ein schweizweites Register zur Koordination der Klagen einzuführen.In Swiss legislation, there is currently no instrument that can ensure effective enforcement of collective damages claims. The amendment of the Swiss Code of Civil Procedure of December 10th, 2021 aims to strengthen collective enforcement by introducing the instrument of class action. However, like similar proposals in the past, the adoption of this amendment has been postponed for the time being due to resistance in the parliament. In the European Union, on the other hand, some member states have already implemented the instrument of class action several years ago. In addition, in 2020 the European Union has issued a directive according to which all member states must now introduce such an instrument to ensure the effective enforcement of collective damages claims. The purpose of this thesis is to identify the strengths and weaknesses of class action in the European Union and to evaluate the draft revision of the Swiss Civil Procedure Code on a comparative basis. The aim of the study is to identify possible risks and to make recommendations on how these can be minimized. To answer the research question, the legal provisions of relevant legal sources including preparatory documents and court decisions were analyzed as primary sources and supplemented with written expert opinions and newspaper reports. Furthermore, a comparison between the legal provisions of the European Union and Switzerland was made in order to evaluate possible improvements. The analysis of the European provisions shows that extensive protection against abuse is guaranteed, but that weaknesses include in particular the dangers of forum shopping, increased legal uncertainty for affected persons due to a large number of ongoing proceedings, and increased attempts to enforce political goals by judicial means. Based on the legal comparison, the Swiss provisions can be evaluated as positive in that the goals of effective collective redress can be achieved and that they also ensure substantial protection against abuse. Negative aspects, however, are the failure to restrict the possibility of third-party financing and forum shopping, as well as the failure to introduce a nationwide electronic register for the coordination of class actions. In order to minimize these weaknesses, it is recommended to adapt the provisions of the draft revision of the Swiss Civil Procedure Code by limiting the third-party financing of a lawsuit by a maximum financing quota and by counteracting forum shopping by more specific jurisdiction rules. In addition, it seems advisable to introduce a nationwide register for the coordination of lawsuits

Seasonal Variation in the Deficiency of 25-Hydroxyvitamin D3 in Mildly to Extremely Obese Subjects

Background: Vitamin D deficiency is a common finding in obese subjects even before any bariatric operation. However, most previous studies reporting on high rates of vitamin D deficiency in obese subjects have not systematically controlled for seasonal variations. Furthermore, the existence of seasonal variation in serum 25-hydroxyvitamin D3 levels has not been well documented in obese subjects so far. Methods: Serum 25-hydroxyvitamin D3 levels were measured in 248 obese subjects (body mass index: range, 30.1-68.9kg/m2). Fat mass was determined using standard bioelectrical impedance analysis. Results: Serum 25-hydroxyvitamin D3 levels decreased with the increasing body mass index and fat mass (both P < 0.001) and showed a marked variation across the seasons of the year (P < 0.001), which was not affected by the degree of obesity. According to the variation in absolute levels, the prevalence of vitamin D deficiency (<50nmol/l) was 3.8-fold higher during winter than during summer (91.2% vs. 24.3%; P < 0.001). Conclusion: Data show a marked seasonal variation in absolute serum 25-hydroxyvitamin D3 concentrations and prevalence of vitamin D deficiency in subjects with mild to extreme obesity. Considering the increasing number of studies reporting on vitamin D deficiency in obesity, the present finding points to season as a crucial factor that should not be neglected when assessing serum levels of this vitamin in obese subject

Monitoring serum concentrations for once-daily netilmicin dosing regimens

A once-daily dosing regimen for aminoglycosides is less expensive, at least as effective and possibly less toxic than multiple-daily dosing regimens. Once-daily dosing might also allow the frequency of measuring the serum concentrations of these antibiotics to be reduced since two of the major objectives of monitoring, high peak and low trough concentrations, are more likely to be achieved with this regimen. A novel strategy for monitoring serum concentrations which relies on a single sample obtained 8 h after a dose, as opposed to both trough and peak samples, is evaluated here. Serum kinetics of netilmicin were studied prospectively in 51 adult patients with initial serum creatinine concentrations of 25 μmol/L was detected in 0 of 7 patients with an 8-h concentration of 6 mg/L. The results of this study suggest that adequate information about serum netilmicin concentrations in patients receiving a once-daily dose may be derived from a sample obtained 8 h after administratio