Acceptance and perceived barriers of implementing a guideline for managing low back in general practice

Background

There is considerable interest today in shared decision-making (SDM), defined as a decision-making process jointly shared by patients and their health care provider. However, the data show that SDM has not been broadly adopted yet. Consequently, the main goal of this proposal is to bring together the resources and the expertise needed to develop an interdisciplinary and international research team on the implementation of SDM in clinical practice using a theory-based dyadic perspective.

Methods

Participants include researchers from Canada, US, UK, and Netherlands, representing medicine, nursing, psychology, community health and epidemiology. In order to develop a collaborative research network that takes advantage of the expertise of the team members, the following research activities are planned: 1) establish networking and on-going communication through internet-based forum, conference calls, and a bi-weekly e-bulletin; 2) hold a two-day workshop with two key experts (one in theoretical underpinnings of behavioral change, and a second in dyadic data analysis), and invite all investigators to present their views on the challenges related to the implementation of SDM in clinical practices; 3) conduct a secondary analyses of existing dyadic datasets to ensure that discussion among team members is grounded in empirical data; 4) build capacity with involvement of graduate students in the workshop and online forum; and 5) elaborate a position paper and an international multi-site study protocol.

Discussion

This study protocol aims to inform researchers, educators, and clinicians interested in improving their understanding of effective strategies to implement shared decision-making in clinical practice using a theory-based dyadic perspective.     

Cell Surface Sialylation and Fucosylation Are Regulated by L1 via Phospholipase Cγ and Cooperate to Modulate Neurite Outgrowth,Cell Survival and Migration

Background

Cell surface glycosylation patterns are markers of cell type and status. However, the mechanisms regulating surface glycosylation patterns remain unknown.

Methodology/Principal Findings

Using a panel of carbohydrate surface markers, we have shown that cell surface sialylation and fucosylation were downregulated in L1^−/y neurons versus L1^+/y neurons. Consistently, mRNA levels of sialyltransferase ST6Gal1, and fucosyltransferase FUT9 were significantly reduced in L1^−/y neurons. Moreover, treatment of L1^+/y neurons with L1 antibodies, triggering signal transduction downstream of L1, led to an increase in cell surface sialylation and fucosylation compared to rat IgG-treated cells. ShRNAs for both ST6Gal1 and FUT9 blocked L1 antibody-mediated enhancement of neurite outgrowth, cell survival and migration. A phospholipase Cγ (PLCγ) inhibitor and shRNA, as well as an Erk inhibitor, reduced ST6Gal1 and FUT9 mRNA levels and inhibited effects of L1 on neurite outgrowth and cell survival.

Conclusions

Neuronal surface sialylation and fucosylation are regulated via PLCγ by L1, modulating neurite outgrowth, cell survival and migration.     

Ebola virus matrix protein VP40 uses the COPII transport system for its intracellular transport

The Ebola virus matrix protein VP40 plays an important role in virion formation and viral egress from cells. However, the host cell proteins and mechanisms responsible for intracellular transport of VP40 prior to its contribution to virion formation remain to be elucidated. Therefore we used coimmunoprecipitation and mass spectrometric analyses to identify host proteins interacting with VP40. We found that Sec24C, a component of the host COPII vesicular transport system, interacts specifically with VP40 via VP40 amino acids 303 to 307. Coimmunoprecipitation and dominant-negative mutant studies indicated that the COPII transport system plays a critical role in VP40 intracellular transport to the plasma membrane. Marburg virus VP40 was also shown to use the COPII transport system for intracellular transport. These findings identify a conserved intersection between a host pathway and filovirus replication, an intersection that can be targeted in the development of new antiviral drugs.     

CCR5Δ32 Genotypes in a German HIV-1 Seroconverter Cohort and Report of HIV-1 Infection in a CCR5Δ32 Homozygous Individual

Background

Homozygosity (Δ32/Δ32) for the 32 bp deletion in the chemokine receptor 5 (CCR5) gene is associated with strong resistance against HIV infection. Heterozygosity is associated with protection of HIV-1 disease progression.

Methodology/Principal Findings

We genotyped a population of 737 HIV-positive adults and 463 healthy controls for the CCR5Δ32 deletion and found heterozygous frequencies of 16.2% (HIV-negative) and 17.5% (HIV-positive) among Caucasian individuals. Analysis of CCR5Δ32 influence on disease progression showed notably lower viral setpoints and a longer time to a CD4 count of <200 µl⁻¹ in seroconverters heterozygous for the deletion. Furthermore, we identified one HIV-positive man homozygous for the Δ32 deletion.

Conclusions/Significance

The protective effect of CCR5 Δ32 heterozygosity is confimed in a large cohort of German seroconverters. The HIV-infected CCR5 Δ32 homozygous individual, however, displays extremely rapid disease progression. This is the 12th case of HIV-infection in this genotype described worldwide.     

Breeding of Brassica rapa for Biogas Production: Heterosis and Combining Ability of Biomass Yield

The use of plant biomass as substrate for biogas production has recently become of major interest in Europe. Winter Brassica rapa produces high early biomass and could be grown as a pre-crop harvested early in the year followed by a second crop such as maize. The objectives of this study were to estimate heterosis and combining ability of 15 European winter B. rapa cultivars for biomass yield at end of flowering. A half-diallel without reciprocals was conducted among cultivars to produce 105 crosses. These crosses and their parents were evaluated in two years at two locations in Northern Germany. Data collected were days to flowering (DTF), fresh biomass yield (FBY), dry matter content (DMC) and dry biomass yield (DBY). The mean DBY was 5.3 t/ha for the parental cultivars and 5.6 t/ha for their crosses. The crosses surpassed on average their parents by 7.6% for FBY and 5.9% for DBY whereas DMC was 1.4% higher in the parents. Maximum mid parent heterosis was 21.0% for FBY and 30.4% for DBY. Analysis of variance showed that genetic variance was mainly due to specific combining ability (SCA). The correlation between parental performance and general combining ability (GCA) was 0.42** for FBY and 0.53** for DBY. In conclusion, the amount of heterosis in crosses between European winter B. rapa cultivars is not very high on average, but can be up to 30% in the best crosses. Selection of parental combinations with high specific combining ability to produce synthetic cultivars can rapidly improve biomass yield.     

Hepatic overexpression of hormone-sensitive lipase and adipose triglyceride lipase promotes fatty acid oxidation, stimulates direct release of free fatty acids, and ameliorates steatosis

Hepatic steatosis is often associated with insulin resistance and obesity and can lead to steatohepatitis and cirrhosis. In this study, we have demonstrated that hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL), two enzymes critical for lipolysis in adipose tissues, also contribute to lipolysis in the liver and can mobilize hepatic triglycerides in vivo and in vitro. Adenoviral overexpression of HSL and/or ATGL reduced liver triglycerides by 40-60% in both ob/ob mice and mice with high fat diet-induced obesity. However, these enzymes did not affect fasting plasma triglyceride and free fatty acid levels or triglyceride and apolipoprotein B secretion rates. Plasma 3-beta-hydroxybutyrate levels were increased 3-5 days after infection in both HSL- and ATGL-overexpressing male mice, suggesting an increase in beta-oxidation. Expression of genes involved in fatty acid transport and synthesis, lipid storage, and mitochondrial bioenergetics was unchanged. Mechanistic studies in oleate-supplemented McA-RH7777 cells with adenoviral overexpression of HSL or ATGL showed that reduced cellular triglycerides could be attributed to increases in beta-oxidation as well as direct release of free fatty acids into the medium. In summary, hepatic overexpression of HSL or ATGL can promote fatty acid oxidation, stimulate direct release of free fatty acid, and ameliorate hepatic steatosis. This study suggests a direct functional role for both HSL and ATGL in hepatic lipid homeostasis and identifies these enzymes as potential therapeutic targets for ameliorating hepatic steatosis associated with insulin resistance and obesity.     

Sphingosine 1-phosphate modulates spinal nociceptive processing

Sphingosine 1-Phosphate (S1P) modulates various cellular functions such as apoptosis, cell differentiation, and migration. Although S1P is an abundant signaling molecule in the central nervous system, very little is known about its influence on neuronal functions. We found that S1P concentrations were selectively decreased in the cerebrospinal fluid of adult rats in an acute and an inflammatory pain model. Pharmacological inhibition of sphingosine kinases (SPHK) decreased basal pain thresholds and SphK2 knock-out mice, but not SphK1 knock-out mice, had a significant decrease in withdrawal latency. Intrathecal application of S1P or sphinganine 1-phosphate (dihydro-S1P) reduced the pain-related (nociceptive) behavior in the formalin assay. S1P and dihydro-S1P inhibited cyclic AMP (cAMP) synthesis, a key second messenger of spinal nociceptive processing, in spinal cord neurons. By combining fluorescence resonance energy transfer (FRET)-based cAMP measurements with Multi Epitope Ligand Cartography (MELC), we showed that S1P decreased cAMP synthesis in excitatory dorsal horn neurons. Accordingly, intrathecal application of dihydro-S1P abolished the cAMP-dependent phosphorylation of NMDA receptors in the outer laminae of the spinal cord. Taken together, the data show that S1P modulates spinal nociceptive processing through inhibition of neuronal cAMP synthesis.     

Structural determinants for Ca2+ and phosphatidylinositol 4,5-bisphosphate binding by the C2A domain of rabphilin-3A

Rabphilin-3A is a neuronal C2 domain tandem containing protein involved in vesicle trafficking. Both its C2 domains (C2A and C2B) are able to bind phosphatidylinositol 4,5-bisphosphate, a key player in the neurotransmitter release process. The rabphilin-3A C2A domain has previously been shown to bind inositol-1,4,5-trisphosphate (IP3; phosphatidylinositol 4,5-bisphosphate headgroup) in a Ca2+-dependent manner with a relatively high affinity (50 microm) in the presence of saturating concentrations of Ca2+. Moreover, IP3 and Ca2+ binding to the C2A domain mutually enhance each other. Here we present the Ca2+-bound solution structure of the C2A domain. Structural comparison with the previously published Ca2+-free crystal structure revealed that Ca2+ binding induces a conformational change of Ca2+ binding loop 3 (CBL3). Our IP3 binding studies as well as our IP3-C2A docking model show the active involvement of CBL3 in IP3 binding, suggesting that the conformational change on CBL3 upon Ca2+ binding enables the interaction with IP3 and vice versa, in line with a target-activated messenger affinity mechanism. Our data provide detailed structural insight into the functional properties of the rabphilin-3A C2A domain and reveal for the first time the structural determinants of a target-activated messenger affinity mechanism.     

On the lattice Boltzmann method simulation of a two-phase flow bioreactor for artificially grown cartilage cells

Owing to the growing demand of cartilage tissue repair and transplants, engineered cartilage cells have emerged as a prospective solution. Several bioreactors were built for artificially grown cartilage cells. In this work, a recently designed flow bed bioreactor is numerically investigated and compared with experimental results.The flow field inside the bioreactor was modelled using the lattice Boltzmann method. The flow consists of two phases which are the liquid component (nutrition supply) and gas component (oxygen supply). The flow field is simulated using the multi-phase lattice Boltzmann method, whilst the cell activity is modelled using Michaelis–Menten kinetics.The oxygen diffusion level at the exit of the nutrition phase is used as an evaluation process between the numerical and experimental results reporting the possibility of using the proposed model to fully simulate such bioreactors, though greatly saving time and money. Shear stress and pressure distributions are as well compared with published human cartilage load measurements to estimate the dynamic similarity between the bioreactor and the human knee. The predicted oxygen levels proved consistent trends with the experimental work with a 7% difference after 1 h measuring time. The shear stress levels recorded 10–11 orders of magnitude lower than in humans and also one order of magnitude lower in the pressure distribution.