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Isolation and characterization of Pisum sativum apyrases, PsNTP9 and PsNTP9-DM, cloned and expressed in Escherichia coli
Adenosine triphosphate (ATP) is widely known as a fuel source for many biochemical processes, and to a lesser degree also as a signaling molecule in plants and animals. When plants are subjected to biotic or abiotic stress or undergoing exocytosis, they release ATP into the extracellular matrix (ECM). The release of ATP sets off a signal transduction pathway, first rapidly increasing the concentrations of cytosolic calcium, reactive oxygen species, and nitric oxide. How these changes specifically influence physiology is the object of much research in both plants and animals. Some of the changes that are affected influence growth and development, stomatal function, and gravitropism. Apyrases and other phosphatases control the concentration of the released nucleotides by breaking phosphate bonds from nucleoside triphosphates and diphosphates. Research aimed at the discovery of receptors, signaling pathway components, and processes has been successful to some extent. There are now known purinergic receptors in both plants and animal cells.
We have cloned a truncated version of Pisum sativum (ps) NTP9. We used a pET-22B vector to add a histidine tag and transformed the vector into the BL21 Escherichia coli with a T7 promoter to enable IPTG induction of the LAC operon and expression of the enzyme. The pET-22B vector was incubated in separate samples with BL21 cells. Cells were propagated, and the expression of recombinant proteins PsNTP9, and separately, a double mutant PsNTP9-DM with a second calmodulin-binding domain, were induced ectopically. Cells were broken open by shaking them and mixing them with lysis buffer. Centrifugation was performed to separate the supernatant containing the released apyrases from the particulate wall fraction. The enzymes were purified by affinity chromatography, then their purity was evaluated by sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE). Western blots were performed to verify presence of the apyrases using a commercial anti-histidine antibody to detect PsNTP9 and PsNTP9-DM. Once suitable amounts of our proteins of interest were harvested, we performed Bradford assays to determine the protein concentration of the samples and carried out an apyrase activity assay to determine the specific activity of the purified enzymes and compare it to that of other known phosphatases.Plant Biolog
Direction of the oblique medial malleolar osteotomy for exposure of the talus
A medial malleolar osteotomy is often indicated for operative exposure of posteromedial osteochondral defects and fractures of the talus. To obtain a congruent joint surface after refixation, the oblique osteotomy should be directed perpendicularly to the articular surface of the tibia at the intersection between the tibial plafond and medial malleolus. The purpose of this study was to determine this perpendicular direction in relation to the longitudinal tibial axis for use during surgery. Using anteroposterior mortise radiographs and coronal computed tomography (CT) scans of 46 ankles (45 patients) with an osteochondral lesion of the talus, two observers independently measured the intersection angle between the tibial plafond and medial malleolus. The bisector of this angle indicated the osteotomy perpendicular to the tibial articular surface. This osteotomy was measured relative to the longitudinal tibial axis on radiographs. Intraclass correlation coefficients (ICC) were calculated to assess reliability. The mean osteotomy was 57.2 ¹ 3.2° relative to the tibial plafond on radiographs and 56.5 ¹ 2.8 on CT scans. This osteotomy corresponded to 30.4 ¹ 3.7° relative to the longitudinal tibial axis. The intraobserver (ICC, 0.90-0.93) and interobserver (ICC, 0.65-0.91) reliability of these measurements were good to excellent. A medial malleolar osteotomy directed at a mean 30° relative to the tibial axis enters the joint perpendicularly to the tibial cartilage, and will likely result in a congruent joint surface after reductio
Credible knowledge: A pilot evaluation of a modified GRADE method using parent-implemented interventions for children with autism
Abstract
Background
Decision-making in child and youth mental health (CYMH) care requires recommendations that are developed through an efficient and effective method and are based on credible knowledge. Credible knowledge is informed by two sources: scientific evidence, and practice-based evidence, that reflects the "real world" experience of service providers. Current approaches to developing these recommendations in relation to CYMH will typically include evidence from one source or the other but do not have an objective method to combine the two. To this end, a modified version of the Grading Recommendations Assessment, Development and Evaluation (GRADE) approach was pilot-tested, a novel method for the CYMH field.
Methods
GRADE has an explicit methodology that relies on input from scientific evidence as well as a panel of experts. The panel established the quality of evidence and derived detailed recommendations regarding the organization and delivery of mental health care for children and youth or their caregivers. In this study a modified GRADE method was used to provide precise recommendations based on a specific CYMH question (i.e. What is the current credible knowledge concerning the effects of parent-implemented, early intervention with their autistic children?).
Results
Overall, it appeared that early, parent-implemented interventions for autism result in positive effects that outweigh any undesirable effects. However, as opposed to overall recommendations, the heterogeneity of the evidence required that recommendations be specific to particular interventions, based on the questions of whether the benefits of a particular intervention outweighs its harms.
Conclusions
This pilot project provided evidence that a modified GRADE method may be an effective and practical approach to making recommendations in CYMH, based on credible knowledge. Key strengths of the process included separating the assessments of the quality of the evidence and the strength of recommendations, transparency in decision-making, and the objectivity of the methods. Most importantly, this method combined the evidence and clinical experience in a more timely, explicit and simple process as compared to previous approaches. The strengths, limitations and modifications of the approach as they pertain to CYMH, are discussed
Associations of homelessness and residential mobility with length of stay after acute psychiatric admission
Background: A small number of patient-level variables have replicated associations with the length of stay (LOS) of psychiatric inpatients. Although need for housing has often been identified as a cause of delayed discharge, there has been little research into the associations between LOS and homelessness and residential mobility (moving to a new home), or the magnitude of these associations compared to other exposures. Methods: Cross-sectional study of 4885 acute psychiatric admissions to a mental health NHS Trust serving four South London boroughs. Data were taken from a comprehensive repository of anonymised electronic patient records. Analysis was performed using log-linear regression. Results: Residential mobility was associated with a 99% increase in LOS and homelessness with a 45% increase. Schizophrenia, other psychosis, the longest recent admission, residential mobility, and some items on the Health of the Nation Outcome Scales (HoNOS), especially ADL impairment, were also associated with increased LOS. Informal admission, drug and alcohol or other non-psychotic diagnosis and a high HoNOS self-harm score reduced LOS. Including residential mobility in the regression model produced the same increase in the variance explained as including diagnosis; only legal status was a stronger predictor. Conclusions: Homelessness and, especially, residential mobility account for a significant part of variation in LOS despite affecting a minority of psychiatric inpatients; for these people, the effect on LOS is marked. Appropriate policy responses may include attempts to avert the loss of housing in association with admission, efforts to increase housing supply and the speed at which it is made available, and reforms of payment systems to encourage this
Anchored Design of Protein-Protein Interfaces
Few existing protein-protein interface design methods allow for extensive backbone rearrangements during the design process. There is also a dichotomy between redesign methods, which take advantage of the native interface, and de novo methods, which produce novel binders.Here, we propose a new method for designing novel protein reagents that combines advantages of redesign and de novo methods and allows for extensive backbone motion. This method requires a bound structure of a target and one of its natural binding partners. A key interaction in this interface, the anchor, is computationally grafted out of the partner and into a surface loop on the design scaffold. The design scaffold's surface is then redesigned with backbone flexibility to create a new binding partner for the target. Careful choice of a scaffold will bring experimentally desirable characteristics into the new complex. The use of an anchor both expedites the design process and ensures that binding proceeds against a known location on the target. The use of surface loops on the scaffold allows for flexible-backbone redesign to properly search conformational space.This protocol was implemented within the Rosetta3 software suite. To demonstrate and evaluate this protocol, we have developed a benchmarking set of structures from the PDB with loop-mediated interfaces. This protocol can recover the correct loop-mediated interface in 15 out of 16 tested structures, using only a single residue as an anchor
Expansion and Characterization of Human Melanoma Tumor-Infiltrating Lymphocytes (TILs)
Various immunotherapeutic strategies for cancer are aimed at augmenting the T cell response against tumor cells. Adoptive cell therapy (ACT), where T cells are manipulated ex vivo and subsequently re-infused in an autologous manner, has been performed using T cells from various sources. Some of the highest clinical response rates for metastatic melanoma have been reported in trials using tumor-infiltrating lymphocytes (TILs). These protocols still have room for improvement and furthermore are currently only performed at a limited number of institutions. The goal of this work was to develop TILs as a therapeutic product at our institution.TILs from 40 melanoma tissue specimens were expanded and characterized. Under optimized culture conditions, 72% of specimens yielded rapidly proliferating TILs as defined as at least one culture reaching âĽ3Ă10(7) TILs within 4 weeks. Flow cytometric analyses showed that cultures were predominantly CD3+ T cells, with highly variable CD4+:CD8+ T cell ratios. In total, 148 independent bulk TIL cultures were assayed for tumor reactivity. Thirty-four percent (50/148) exhibited tumor reactivity based on IFN-Îł production and/or cytotoxic activity. Thirteen percent (19/148) showed specific cytotoxic activity but not IFN-Îł production and only 1% (2/148) showed specific IFN-Îł production but not cytotoxic activity. Further expansion of TILs using a 14-day "rapid expansion protocol" (REP) is required to induce a 500- to 2000-fold expansion of TILs in order to generate sufficient numbers of cells for current ACT protocols. Thirty-eight consecutive test REPs were performed with an average 1865-fold expansion (+/- 1034-fold) after 14 days.TILs generally expanded efficiently and tumor reactivity could be detected in vitro. These preclinical data from melanoma TILs lay the groundwork for clinical trials of ACT
Aurora-A overexpression enhances cell-aggregation of Ha-ras transformants through the MEK/ERK signaling pathway
<p>Abstract</p> <p>Background</p> <p>Overexpression of Aurora-A and mutant Ras (Ras<sup>V12</sup>) together has been detected in human bladder cancer tissue. However, it is not clear whether this phenomenon is a general event or not. Although crosstalk between Aurora-A and Ras signaling pathways has been reported, the role of these two genes acting together in tumorigenesis remains unclear.</p> <p>Methods</p> <p>Real-time PCR and sequence analysis were utilized to identify Ha- and Ki-<it>ras </it>mutation (Gly -> Val). Immunohistochemistry staining was used to measure the level of Aurora-A expression in bladder and colon cancer specimens. To reveal the effect of overexpression of the above two genes on cellular responses, mouse NIH3T3 fibroblast derived cell lines over-expressing either Ras<sup>V12</sup>and wild-type Aurora-A (designated WT) or Ras<sup>V12 </sup>and kinase-inactivated Aurora-A (KD) were established. MTT and focus formation assays were conducted to measure proliferation rate and focus formation capability of the cells. Small interfering RNA, pharmacological inhibitors and dominant negative genes were used to dissect the signaling pathways involved.</p> <p>Results</p> <p>Overexpression of wild-type Aurora-A and mutation of Ras<sup>V12 </sup>were detected in human bladder and colon cancer tissues. Wild-type Aurora-A induces focus formation and aggregation of the Ras<sup>V12 </sup>transformants. Aurora-A activates Ral A and the phosphorylation of AKT as well as enhances the phosphorylation of MEK, ERK of WT cells. Finally, the Ras/MEK/ERK signaling pathway is responsible for Aurora-A induced aggregation of the Ras<sup>V12 </sup>transformants.</p> <p>Conclusion</p> <p>Wild-type-Aurora-A enhances focus formation and aggregation of the Ras<sup>V12 </sup>transformants and the latter occurs through modulating the Ras/MEK/ERK signaling pathway.</p
Effectiveness of physical therapy interventions for children with cerebral palsy: A systematic review
Background
To assess the effectiveness of physical therapy (PT) interventions on functioning in children with cerebral palsy (CP).
Methods
A search was made in Medline, Cinahl, PEDro and the Cochrane library for the period 1990 to February 2007. Only randomized controlled trials (RCTs) on PT interventions in children with diagnosed CP were included. Two reviewers independently assessed the methodological quality and extracted the data. The outcomes measured in the trials were classified using the International Classification of Functioning, Disability and Health (ICF).
Results
Twenty-two trials were identified. Eight intervention categories were distinguished. Four trials were of high methodological quality. Moderate evidence of effectiveness was established for two intervention categories: effectiveness of upper extremity treatments on attained goals and active supination, and of prehensile hand treatment and neurodevelopmental therapy (NDT) or NDT twice a week on developmental status, and of constraint-induced therapy on amount and quality of hand use. Moderate evidence of ineffectiveness was found of strength training on walking speed and stride length. Conflicting evidence was found for strength training on gross motor function. For the other intervention categories the evidence was limited due to low methodological quality and the statistically insignificant results of the studies.
Conclusion
Due to limitations in methodological quality and variations in population, interventions and outcomes, mostly limited evidence on the effectiveness of most PT interventions is available through RCTs. Moderate evidence was found for some effectiveness of upper extremity training. Well-designed trials are needed especially for focused PT interventions.BioMed Central Open acces
INCITE: A randomised trial comparing constraint induced movement therapy and bimanual training in children with congenital hemiplegia
Background: Congenital hemiplegia is the most common form of cerebral palsy (CP) accounting for 1 in 1300 live births. These children have limitations in capacity to use the impaired upper limb and bimanual coordination deficits which impact on daily activities and participation in home, school and community life. There are currently two diverse intensive therapy approaches. Traditional therapy has adopted a bimanual approach (BIM training) and recently, constraint induced movement therapy (CIMT) has emerged as a promising unimanual approach. Uncertainty remains about the efficacy of these interventions and characteristics of best responders. This study aims to compare the efficacy of CIMT to BIM training to improve outcomes across the ICF for school children with congenital hemiplegia
Sequence comparison of prefrontal cortical brain transcriptome from a tame and an aggressive silver fox (Vulpes vulpes)
<p>Abstract</p> <p>Background</p> <p>Two strains of the silver fox (<it>Vulpes vulpes</it>), with markedly different behavioral phenotypes, have been developed by long-term selection for behavior. Foxes from the tame strain exhibit friendly behavior towards humans, paralleling the sociability of canine puppies, whereas foxes from the aggressive strain are defensive and exhibit aggression to humans. To understand the genetic differences underlying these behavioral phenotypes fox-specific genomic resources are needed.</p> <p>Results</p> <p>cDNA from mRNA from pre-frontal cortex of a tame and an aggressive fox was sequenced using the Roche 454 FLX Titanium platform (> 2.5 million reads & 0.9 Gbase of tame fox sequence; >3.3 million reads & 1.2 Gbase of aggressive fox sequence). Over 80% of the fox reads were assembled into contigs. Mapping fox reads against the fox transcriptome assembly and the dog genome identified over 30,000 high confidence fox-specific SNPs. Fox transcripts for approximately 14,000 genes were identified using SwissProt and the dog RefSeq databases. An at least 2-fold expression difference between the two samples (p < 0.05) was observed for 335 genes, fewer than 3% of the total number of genes identified in the fox transcriptome.</p> <p>Conclusions</p> <p>Transcriptome sequencing significantly expanded genomic resources available for the fox, a species without a sequenced genome. In a very cost efficient manner this yielded a large number of fox-specific SNP markers for genetic studies and provided significant insights into the gene expression profile of the fox pre-frontal cortex; expression differences between the two fox samples; and a catalogue of potentially important gene-specific sequence variants. This result demonstrates the utility of this approach for developing genomic resources in species with limited genomic information.</p
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