On two theorems for flat, affine group schemes over a discrete valuation ring

We include short and elementary proofs of two theorems characterizing reductive group schemes over a discrete valuation ring, in a slightly more general context.Comment: 10 pages. To appear in C. E. J.

The structure of blocks with a Klein four defect group

We prove Erdmann’s conjecture [16] stating that every block with a Klein four defect group has a simple module with trivial source, and deduce from this that Puig’s finiteness conjecture holds for source algebras of blocks with a Klein four defect group. The proof uses the classification of finite simple groups

Acute phase response in two consecutive experimentally induced E. coli intramammary infections in dairy cows

<p>Abstract</p> <p>Background</p> <p>Acute phase proteins haptoglobin (Hp), serum amyloid A (SAA) and lipopolysaccharide binding protein (LBP) have suggested to be suitable inflammatory markers for bovine mastitis. The aim of the study was to investigate acute phase markers along with clinical parameters in two consecutive intramammary challenges with <it>Escherichia coli </it>and to evaluate the possible carry-over effect when same animals are used in an experimental model.</p> <p>Methods</p> <p>Mastitis was induced with a dose of 1500 cfu of <it>E. coli </it>in one quarter of six cows and inoculation repeated in another quarter after an interval of 14 days. Concentrations of acute phase proteins haptoglobin (Hp), serum amyloid A (SAA) and lipopolysaccharide binding protein (LBP) were determined in serum and milk.</p> <p>Results</p> <p>In both challenges all cows became infected and developed clinical mastitis within 12 hours of inoculation. Clinical disease and acute phase response was generally milder in the second challenge. Concentrations of SAA in milk started to increase 12 hours after inoculation and peaked at 60 hours after the first challenge and at 44 hours after the second challenge. Concentrations of SAA in serum increased more slowly and peaked at the same times as in milk; concentrations in serum were about one third of those in milk. Hp started to increase in milk similarly and peaked at 36–44 hours. In serum, the concentration of Hp peaked at 60–68 hours and was twice as high as in milk. LBP concentrations in milk and serum started to increase after 12 hours and peaked at 36 hours, being higher in milk. The concentrations of acute phase proteins in serum and milk in the <it>E. coli </it>infection model were much higher than those recorded in experiments using Gram-positive pathogens, indicating the severe inflammation induced by <it>E. coli</it>.</p> <p>Conclusion</p> <p>Acute phase proteins would be useful parameters as mastitis indicators and to assess the severity of mastitis. If repeated experimental intramammary induction of the same animals with <it>E. coli </it>is used in cross-over studies, the interval between challenges should be longer than 2 weeks, due to the carry-over effect from the first infection.</p

Stone Age Yersinia pestis genomes shed light on the early evolution, diversity, and ecology of plague

The bacterial pathogenYersinia pestisgave rise to devastating outbreaks throughouthuman history, and ancient DNA evidence has shown it afflicted human populations asfar back as the Neolithic.Y. pestisgenomes recovered from the Eurasian Late Neolithic/Early Bronze Age (LNBA) period have uncovered key evolutionary steps that led to itsemergence from aYersinia pseudotuberculosis-like progenitor; however, the number ofreconstructed LNBA genomes are too few to explore its diversity during this criticalperiod of development. Here, we present 17Y. pestisgenomes dating to 5,000 to 2,500y BP from a wide geographic expanse across Eurasia. This increased dataset enabled usto explore correlations between temporal, geographical, and genetic distance. Ourresults suggest a nonflea-adapted and potentially extinct single lineage that persistedover millennia without significant parallel diversification, accompanied by rapid dis-persal across continents throughout this period, a trend not observed in other pathogensfor which ancient genomes are available. A stepwise pattern of gene loss provides fur-ther clues on its early evolution and potential adaptation. We also discover the presenceof theflea-adapted form ofY. pestisin Bronze Age Iberia, previously only identified inin the Caucasus and the Volga regions, suggesting a much wider geographic spread ofthis form ofY. pestis. Together, these data reveal the dynamic nature of plague’s forma-tive years in terms of its early evolution and ecology

Cellular glycosylation affects Herceptin binding and sensitivity of breast cancer cells to doxorubicin and growth factors

Alterations in protein glycosylation are a key feature of oncogenesis and have been shown to affect cancer cell behaviour perturbing cell adhesion, favouring cell migration and metastasis. This study investigated the effect of N-linked glycosylation on the binding of Herceptin to HER2 protein in breast cancer and on the sensitivity of cancer cells to the chemotherapeutic agent doxorubicin (DXR) and growth factors (EGF and IGF-1). The interaction between Herceptin and recombinant HER2 protein and cancer cell surfaces (on-rate/off-rate) was assessed using a quartz crystal microbalance biosensor revealing an increase in the accessibility of HER2 to Herceptin following deglycosylation of cell membrane proteins (deglycosylated cells Bmax: 6.83 Hz; glycosylated cells Bmax: 7.35 Hz). The sensitivity of cells to DXR and to growth factors was evaluated using an MTT assay. Maintenance of SKBR-3 cells in tunicamycin (an inhibitor of N-linked glycosylation) resulted in an increase in sensitivity to DXR (0.1 µM DXR P<0.001) and a decrease in sensitivity to IGF-1 alone and to IGF-1 supplemented with EGF (P<0.001). This report illustrates the importance of N-linked glycosylation in modulating the response of cancer cells to chemotherapeutic and biological treatments and highlights the potential of glycosylation inhibitors as future combination treatments for breast cancer

Surface pretreatments for medical application of adhesion

Medical implants and prostheses (artificial hips, tendono- and ligament plasties) usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques , connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m). This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body

Factors contributing to attrition behavior in diabetes self-management programs: A mixed method approach

<p>Abstract</p> <p>Background</p> <p>Diabetes self-management education is a critical component in diabetes care. Despite worldwide efforts to develop efficacious DSME programs, high attrition rates are often reported in clinical practice. The objective of this study was to examine factors that may contribute to attrition behavior in diabetes self-management programs.</p> <p>Methods</p> <p>We conducted telephone interviews with individuals who had Type 2 diabetes (n = 267) and attended a diabetes education centre. Multivariable logistic regression was performed to identify factors associated with attrition behavior. Forty-four percent of participants (n = 118) withdrew prematurely from the program and were asked an open-ended question regarding their discontinuation of services. We used content analysis to code and generate themes, which were then organized under the Behavioral Model of Health Service Utilization.</p> <p>Results</p> <p>Working full and part-time, being over 65 years of age, having a regular primary care physician or fewer diabetes symptoms were contributing factors to attrition behaviour in our multivariable logistic regression. The most common reasons given by participants for attrition from the program were conflict between their work schedules and the centre's hours of operation, patients' confidence in their own knowledge and ability when managing their diabetes, apathy towards diabetes education, distance to the centre, forgetfulness, regular physician consultation, low perceived seriousness of diabetes, and lack of familiarity with the centre and its services. There was considerable overlap between our quantitative and qualitative results.</p> <p>Conclusion</p> <p>Reducing attrition behaviour requires a range of strategies targeted towards delivering convenient and accessible services, familiarizing individuals with these services, increasing communication between centres and their patients, and creating better partnerships between centres and primary care physicians.</p

Demonstration of age-dependent capsular material on Pasteurella haemolytica serotype 1

Extracellular capsular material was demonstrated on early log-phase cells of Pasteurella haemolytica serotype 1 by the fluorescent-antibody and several capsular staining techniques. The presence of this material was shown to be age dependent. Wide capsules were demonstrable on cells from 2- to 12-h cultures, whereas cells from 16- to 22-h cultures had very little cell-associated capsular material. The Maneval technique most clearly demonstrated the presence of capsules on cells from young (6-h) cultures when compared with other capsule staining techniques.Not peer reviewedVeterinary Parasitology, Microbiology and Public HealthPatholog

Proteomic Analyses of Host and Pathogen Responses during Bovine Mastitis

The pursuit of biomarkers for use as clinical screening tools, measures for early detection, disease monitoring, and as a means for assessing therapeutic responses has steadily evolved in human and veterinary medicine over the past two decades. Concurrently, advances in mass spectrometry have markedly expanded proteomic capabilities for biomarker discovery. While initial mass spectrometric biomarker discovery endeavors focused primarily on the detection of modulated proteins in human tissues and fluids, recent efforts have shifted to include proteomic analyses of biological samples from food animal species. Mastitis continues to garner attention in veterinary research due mainly to affiliated financial losses and food safety concerns over antimicrobial use, but also because there are only a limited number of efficacious mastitis treatment options. Accordingly, comparative proteomic analyses of bovine milk have emerged in recent years. Efforts to prevent agricultural-related food-borne illness have likewise fueled an interest in the proteomic evaluation of several prominent strains of bacteria, including common mastitis pathogens. The interest in establishing biomarkers of the host and pathogen responses during bovine mastitis stems largely from the need to better characterize mechanisms of the disease, to identify reliable biomarkers for use as measures of early detection and drug efficacy, and to uncover potentially novel targets for the development of alternative therapeutics. The following review focuses primarily on comparative proteomic analyses conducted on healthy versus mastitic bovine milk. However, a comparison of the host defense proteome of human and bovine milk and the proteomic analysis of common veterinary pathogens are likewise introduced