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The aim of this study was to compare the microtensile bond strength of 3 bulkfill composites with 2 polymerisation modes: continuous and progressive. Twenty-four healthy human molars were occlusally reduced by 4 mm (Exakt Technology Inc Kg of Norderstedt, Germany), etched with 35% phosphoric acid for 15 seconds, then a layer of adhesive was applied. Each group received 1 type of bulkfill composite : 1) group 1 (n=6): Smart dentin replacement "SDR?" (Dentsply / Caulk®, Milford, DE, USA); 2) group 2 (n=6): Tetric N Ceram® bulk fill "TNC®" (Ivoclar, Vivadent, Schaan Liechtenstein), 3) group 3 (n=6): Filtek Bulkfill "FB" (3M, ESPE, Seefeld, Germany) and 4) group 4 (n=6): a nano-hybrid composite Z250 XT (3M, ESPE, Seefeld, Germany). Each group underwent two types of polymerization (n = 3): continuous polymerization and ramping polymerization. Each tooth was then cut into sections of 1 mm2. Specimens were hooked to a universal machine YL-01 (YLE GmbH Waldstraße 1/1a, 64732 Bad König, Germany) and a pulling force was applied to each specimen at a speed of 1 mm/min. This study showed that with LED continuous polymerization mode or ramping polymerization mode, the average tearing force was significantly different between the 4 types of composites (p = 0.006 < 0.05, p < 0.0001, respectively). The mean value of tearing was the following: TNC® < FB < Z250XT < SDR™. Finally, the average tearing force was significantly different between the bulkfill composites when using the same type of polymerization. The value of tearing is always lower in continuous polymerization in comparison to the ramping polymerization. SDR™ had the lowest value of retraction and polymerization stress when compared to the TNC® and FB, resulting in a better adaptation of the restoration. Furthermore, while comparing the 2 types of polymerization, we concluded that the ramping mode gives less retraction and polymerization stress than the continuous mode, thereby, a better adaptation of restoration. [ABSTRACT FROM AUTHOR]

Legionellae constitute a frequent contamination of warm water systems and can lead to serious infections. Therefore, in many countries it is mandatory to monitor warm water systems for their presence. The method of examination in Germany is regulated by guideline ISO 11731 and DIN EN ISO 11731-2, and the results are reported as concentration of Legionella spp. Only limited information is available on the presence of individual species of Legionellae in the examined systems, since most investigations and research focus solely on Legionella pneumophila as the most important human pathogen. In this study 76,220 samples obtained from 13,397 warm water systems originating from 24 different zip code districts covering an area of more than 71,000km2 in southern Germany were examined. This resulted in the identification of 47,924 Legionella isolates to the species level using a MALDI-TOF mass spectrometry-based method. Legionella species distribution was analyzed with respect to warm water system type, geographic region (defined as zip code district) and temperature during sample taking. Overall, 20.7% of the samples were found positive for Legionella species and 14 different species of Legionella were recovered. These were not equally present throughout the geographic area investigated, but instead an individual regional diversity of Legionella species was observed for the examined zip code districts. Although Legionella pneumophila represented 84% of all contaminations found, depending on the geographical region its proportion varied substantially between 57.5% and 91.2%. The occurrence of other species was also of importance since they accounted for up to 42% of contaminations regionally, with Legionella londiniensis being most prominent representing up to 38.8% of recovered colonies. In addition, the influence of temperature on the individual species was disparate, but the temperature range between 50°C and 59°C was identified as the optimal condition for facilitating emergence of the majority of recovered Legionella species. The identification of Legionella to the species level by MALDI-TOF allowed for a more concise depiction of the regional distribution and the ecology of this genus, and may be of additional value when counter measures need to be initiated. [ABSTRACT FROM AUTHOR]

Using partial least square discriminate analysis (PLSDA), we studied the spectroscopic differences between the commonly used filler-binder microcrystalline cellulose (MCC) from five manufactures. These samples had subtle differences in the chemical and physical properties, which are often the cause of differences in excipient performance. Studying these differences allowed us to build and validate a model to classify five manufacturers of MCC using near-infrared (NIR) spectra. The sample training set includes 39 MCC samples collected from five manufactures with regions spanning the United States of America, Japan, Taiwan, Germany, and Brazil. The samples from individual manufacturers include diverse grades that differ in moisture content, particle size, and bulk density. Optimized pretreatment methods were identified as standard normal variate normalization, followed by Savitzky-Golay second derivative, mean centering, and orthogonal signal correction. The model was optimized with cross-validation and validated with an independent sample set comprising nine samples collected from those five manufacturers. The results showed that none of the samples in the independent validation set was misclassified. The score and loading plots revealed that the differences in content of oxidized cellulose group, water content and states, hydrogen bonding, and degree of polymerization of the MCC samples are responsible for the class differentiation. Permutation test demonstrated that the outcome of the PLSDA model was significantly different from that of the randomly generated model. The advantages and limitations of the method in this type of application were discussed. [ABSTRACT FROM AUTHOR]

At present worldwide about 45% of the manufactured plastic materials and 40% of synthetic rubber are obtained by free radical polymerization processes. The first free radically synthesized polymers were produced between 1910 and 1930 by initiation with peroxy compounds. In the 1940s the polymerization by redox processes was found independently and simultaneously at IG Farben in Germany and ICI in Great Britain. In the 1950s the systematic investigation of azo compounds as free radical initiators followed. Compounds with labile C-C-bonds were investigated as initiators only in the period from the end of the 1960s until the early 1980s. At about the same time, iniferters with cleavable S-S-bonds were studied in detail. Both these initiator classes can be designated as predecessors for "living" or controlled free radical polymerizations with nitroxyl-mediated polymerizations, reversible addition fragmentation chain transfer processes (RAFT), and atom transfer radical polymerizations (ATRP). [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to evaluate the kinetics of conversion of Scotchbond Multi-purpose Plus (3M ESPE, St Paul, MN) and Prime&Bond NT (Dentsply De Trey, Konstanz, Germany) used in light-cured, self-cured, or dual-cured versions. The adhesive systems were used in the light-cured version (without the use of chemical initiator) or mixed with its respective chemical initiator either with light activation (dual-cured) or not (self-cured). The degree of conversion (DC) was monitored as a function of time during 5 minutes with a Fourier transform infrared spectrometer equipped with an attenuated total reflectance device. Light-cured and dual-cured modes of Scotchbond Multi-purpose Plus presented the highest DC at 5 minutes. The addition of the self-cure activator (dual-cured mode) to Prime&Bond NT reduced the DC. For the self-cured versions, only the Scotchbond Multi-purpose Plus presented any polymerization reaction at 5 minutes. For the two bonding systems tested, it appears that light curing of the adhesive is important in order to reach a high DC in the first moments after the bonding procedure. [Copyright &y& Elsevier]

The aim of this prospective study was to evaluate the prevalence of feline haemotropic mycoplasmas in Germany, to determine probable risk factors for these infections and to compare the diagnostic value of microscopic examination of blood smears to polymerase chain reaction (PCR). For the prevalence study, convenience samples (Ethylene diamine-tetraacetic acid (EDTA) blood) from 262 (64.5% male and 35.5% female) cats were included. A PCR for the detection of Mycoplasma haemofelis (MHF) and ‘Candidatus Mycoplasma haemominutum’ (CMH) as well as a feline leukaemia virus (FeLV)/feline immunodeficiency virus (FIV) enzyme-linked immunoassay was performed. Blood smears from 224 cats were examined and the sensitivity and specificity of the microscopic diagnosis were determined. The prevalence of CMH, MHF, and CMH/MHF co-infection was 22.5%, 4.5%, and 0.8%, respectively. CMH was significantly associated with male gender (P =0.047), older age (P =0.0015) and both FeLV (P =0.002) and FIV infections (P <0.0001). However, there was no association between the presence of anaemia and CMH/MHF infection. The respective sensitivity and specificity of the microscopic diagnosis were 10.3% and 87.1% for a CMH infection and 0.0% and 98.0% for MHF infection. [Copyright &y& Elsevier]

Most studies on the species composition of arbuscular mycorrhizal fungi (AMF) have solely analysed mycorrhizal roots or AM spores collected from soil samples. However, the spore production rate and proportions of AMF mycelium in roots and soils have all been shown to vary substantially in a taxon-specific manner. Therefore, in the study presented here we used a molecular approach to analyse the species composition of AMF in spores, intra-radical and extra-radical mycelium in an intensively farmed meadow in central Germany. By polymerase chain reaction and sequencing of the ITS region members of seven different families and species groups within Glomeromycota were identified. The data revealed remarkable differences in the composition of AMF taxa both between the spores and the mycelia, and between the two types of mycelia. Glomus group Ab was dominant in roots and spores, in accordance with previous research. However, members of this group were rarely detected as extra-radical mycelium, in which Paraglomeraceae were dominant, although we found no evidence for the presence of Paraglomeraceae in roots or spores, even when a specific primer set was used. These results may be interpreted as a further indication that AMF are not necessarily obligate symbionts of plants. [ABSTRACT FROM AUTHOR]

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Objective: To develop a method of freezing small amounts of spermatozoa in polymerized alginic acid drops, which can be liquified after thawing for recovery of the spermatozoa. Design: Prospective clinical study. Setting: Medical School, RWTH Aachen, Aachen Germany. Patient(s): None. Intervention(s): Validation of the encapsulation method with bovine sperm; cryopreservation of human spermatozoa in alginic capsules. Main Outcome Measure(s): We optimized the cryopreservation method by testing different parameters influencing the freezing procedure, such as concentration of alginic acid, size of drops, time of polymerization, and culture media. Result(s): The final protocol was as follows: encapsulation by 7.3 mg/mL alginic acid forming 10-μL drops polymerized for 30 seconds and liquefied for 2.5 minutes in sodium citrate. Cryopreservation of human spermatozoa by this protocol resulted in a decreased motility of 18.3% compared with standard protocols but a 19.9% higher vitality of the immotile spermatozoa. Conclusion(s): No difference in viability of spermatozoa after both sperm-freezing procedures could be observed. Further investigation will be undertaken to reduce the amount of immotile but viable sperm after microencapsulation in alginic acid. [Copyright &y& Elsevier]

Total DNA of Plasmopara halstedii isolates from Germany was analysed for polymorphisms potentially useful for the differentiation of field isolates with respect to epidemiological studies or pathotype characterization. The isolation of the DNA started from mitotically formed zoosporangia, which is the only cellular structure of the biotrophic pathogen accessible independently from its host. The total DNA of the pathogen was used to perform DNA fingerprints with minisatellite and simple-sequence repeat primers. Polymorphisms were found that allowed differentiation on the level of single field isolates; however, they were not correlated with either physiological races or the geographic origin of the isolates. Using such differentiating primers, single spore strains of three pathogen isolates were also analysed with respect to genetic homogeneity. Minor variation was visible in the mitotically derived offspring, but the overall appearance of these patterns was mostly uniform with those of the respective parental isolate.Key words: Plasmopara halstedii, polymerase chain reaction (PCR), simple sequences, mitochondrial DNA, Helianthus annuus.L'ADN total d'isolats de Plasmopara halstedii provenant d'Allemagne a été analysé pour rechercher des polymorphismes qui pourraient éventuellement servir à distinguer les souches isolées sur le terrain par rapport aux études épidémiologiques ou la caractérisation du pathotype. L'isolement de l'ADN s'est fait à partir des zoosporanges formés à la mitose qui sont la seule structure cellulaire de ce pathogène biotrophe accessible indépendamment de son hôte. L'ADN total du pathogène a été utilisé pour obtenir des empreintes d'ADN à l'aide de minisatellites et d'amorces pour les répétitions simples de séquence. Nous avons trouvé des polymorphismes qui permettaient de différencier les isolats au niveau d'un seul champ mais, par contre, ces polymorphismes ne présentaient pas de corrélation avec les types physiologiques ou l'origine géographique des isolats. À l'aide de telles amorces de différenciation, des souches ne produisant qu'une seule spore représentant trois isolats pathogènes ont aussi été analysées en fonction de leur homogénéité génétique. Une variation mineure a pu être notée dans la progéniture dérivée de la mitose, mais globalement les profils obtenus étaient presque totalement conformes à ceux des isolats parentaux respectifs.Mots clés : Plasmopara halstedii, réaction en chaîn de la polymérase (PCR), séquences simples, ADN mitochondrial, Helianthus annuus.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Introduction: The purpose of this study was to investigate the influence of both polymerization cycles and mechanical exposure procedures on the adhesion of instrument fragments using a modified tube technique with a light-curing composite., Methods: Eighty Mtwo instruments (size 15.05; VDW, Munich, Germany) were cut at a diameter of 35/100 mm and clamped in a vice with an overlap of 2 mm. Matching cannulas were filled with SDR composite (Dentsply, York, PA) and placed over the instruments. Prime & Bond Active (Dentsply Sirona, Bensheim, Germany) was used as the bonding material. Glass fiber was inserted from the opposite side into the cannula, and 1, 2, 4, or 6 polymerization cycles of 30 seconds were applied (800 mW/mm 2 ) (n = 20/group). Sixty further identical instruments (n = 20/group) were divided into the following groups: group 1, cut at 10 mm and left unprepared (taper = 5%); group 2, parallelized using diamond instruments (taper = 0%); and group 3, prepared in a way that an inverted conical taper resulted (taper = 2%). Polymerization was performed for 2 minutes. The failure load and mode of failure were determined using a tensile testing device (2 mm/min). Data were statistically analyzed using the Kruskal-Wallis or chi-square test., Results: The failure load increased significantly with the number of polymerization cycles (P < .0001). More than 4 polymerization cycles had no further benefit (P > .05). The failure load in the inverted conical group was significantly lower (P < .0001) compared with the parallel and the unprepared groups. Adhesive failure was significantly more frequent in groups 2 and 3 (20/20) than in group 1 (16/20) (P < .05)., Conclusions: Both the number of polymerization cycles and the mechanical exposure procedures had a significant impact on the adhesive force when using the tube technique., (Copyright © 2020 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Germany's BYK-Chemie GmbH has extended its product range with the introduction of two new additives that are reported to increase the scratch resistance of polyolefin-based surfaces and components. [Copyright &y& Elsevier]

Abstract: Profilin 1 is a central regulator of actin dynamics. Mutations in the gene profilin 1 (PFN1) have very recently been shown to be the cause of a subgroup of amyotrophic lateral sclerosis (ALS). Here, we performed a large screen of US, Nordic, and German familial and sporadic ALS and frontotemporal dementia (FTLD) patients for PFN1 mutations to get further insight into the spectrum and pathogenic relevance of this gene for the complete ALS/FTLD continuum. Four hundred twelve familial and 260 sporadic ALS cases and 16 ALS/FTLD cases from Germany, the Nordic countries, and the United States were screened for PFN1 mutations. Phenotypes of patients carrying PFN1 mutations were studied. In a German ALS family we identified the novel heterozygous PFN1 mutation p.Thr109Met, which was absent in controls. This novel mutation abrogates a phosphorylation site in profilin 1. The recently described p.Gln117Gly sequence variant was found in another familial ALS patient from the United States. The ALS patients with mutations in PFN1 displayed spinal onset motor neuron disease without overt cognitive involvement. PFN1 mutations were absent in patients with motor neuron disease and dementia, and in patients with only FTLD. We provide further evidence that PFN1 mutations can cause ALS as a Mendelian dominant trait. Patients carrying PFN1 mutations reported so far represent the “classic” ALS end of the ALS-FTLD spectrum. The novel p.Thr109Met mutation provides additional proof-of-principle that mutant proteins involved in the regulation of cytoskeletal dynamics can cause motor neuron degeneration. Moreover, this new mutation suggests that fine-tuning of actin polymerization by phosphorylation of profilin 1 might be necessary for motor neuron survival. [Copyright &y& Elsevier]