Deciphering of ADP-induced, phosphotyrosine-dependent signaling networks in human platelets by Src-homology 2 region (SH2)-profiling.

Tyrosine phosphorylation plays a central role in signal transduction controlling many important biological processes. In platelets, the activity of several signaling proteins is controlled by tyrosine phosphorylation ensuring proper platelet activation and aggregation essential for regulation of the delicate balance between bleeding and hemostasis. Here, we applied Src-homology 2 region (SH2)-profiling for deciphering of the phosphotyrosine state of human platelets activated by adenosine diphosphate (ADP). Applying a panel of 31 SH2-domains, rapid and complex regulation of the phosphotyrosine state of platelets was observed after ADP stimulation. Specific inhibition of platelet P2Y receptors by synthetic drugs revealed a major role for the P2Y1 receptor in tyrosine phosphorylation. Concomitant activation of protein kinase A (PKA) abolished ADP-induced tyrosine phosphorylation in a time and concentration-dependent manner. Given the fact that PKA activity is negatively regulated by the P2Y12 receptor, our data provide evidence for a novel link of synergistic control of the state of tyrosine phosphorylation by both P2Y receptors. By SH2 domain pull down and MS/MS analysis, we identified distinct tyrosine phosphorylation sites in cell adhesion molecules, intracellular adapter proteins and phosphatases suggesting a major, functional role of tyrosine phosphorylation of theses candidate proteins in ADP-dependent signaling in human platelets.

A post-market cluster randomized controlled trial of the effect of the TENA SmartCare Change Indicator™ on urinary continence care efficiency and skin health in older nursing home residents.

BACKGROUND: Urinary continence care for residents of nursing homes who are unable to communicate their toileting needs usually involves care aides manually checking continence products (pads) to determine the level of urine saturation prior to changing. The TENA SmartCare Change Indicator is a medical device which estimates urine saturation and notifies caregivers of the optimal time for pad changes. This study will seek to examine the effect of the TENA SmartCare Change Indicator on urinary continence care efficiency and skin health, in comparison to usual care. METHODS: This cluster randomized controlled trial (NCT05247047) involving older nursing home residents with urinary incontinence unable to consistently indicate their toileting needs, and their care aides, will compare technology-based and usual continence care over a period of 8 weeks. Co-primary endpoints of superiority in continence care efficiency and non-inferiority in the maintenance of skin health will be assessed. Secondary outcomes will examine the resident quality of life, sleep quality, responsive behaviours, changes in pad use and leakage episodes outside the pad. Change in care aide work engagement, job satisfaction and rushed tasks will be assessed. Benefits and challenges with the use of the device for continence care will be identified from the perspectives of the care staff. DISCUSSION: Urinary continence assessment and care in nursing homes is reported as suboptimal and threatening to dignity. Data on the utility and effect of technological solutions for improving urinary continence care are few and conflicting. If shown effective, this technological solution has the potential to improve the care for older residents and improve the working lives of caregiving staff who look after this most vulnerable section of the population. TRIAL REGISTRATION: ClinicalTrials.gov NCT05247047. Registration date is Feb 18, 2022.

Salivary and pellicle proteome: A datamining analysis.

We aimed to comprehensively compare two compartmented oral proteomes, the salivary and the dental pellicle proteome. Systematic review and datamining was used to obtain the physico-chemical, structural, functional and interactional properties of 1,515 salivary and 60 identified pellicle proteins. Salivary and pellicle proteins did not differ significantly in their aliphatic index, hydrophaty, instability index, or isoelectric point. Pellicle proteins were significantly more charged at low and high pH and were significantly smaller (10-20 kDa) than salivary proteins. Protein structure and solvent accessible molecular surface did not differ significantly. Proteins of the pellicle were more phosphorylated and glycosylated than salivary proteins. Ion binding and enzymatic activities also differed significantly. Protein-protein-ligand interaction networks relied on few key proteins. The identified differences between salivary and pellicle proteins could guide proteome compartmentalization and result in specialized functionality. Key proteins could be potential targets for diagnostic or therapeutic application.

Selective or stepwise removal of deep caries in deciduous molars: study protocol for a randomized controlled trial.

BACKGROUND: For treating deep caries lesions, selective or stepwise (one- and two-step) incomplete excavation seems advantageous compared with complete caries removal. However, current evidence regarding the success, as defined by not requiring any retreatments, or survival of teeth after different excavations is insufficient for definitive recommendation, especially when treating deciduous teeth. Moreover, restoration integrity has not been comparatively analyzed longitudinally, and neither patients', dentists' or parents' preferences nor the clinical long-term costs emanating from both initial and retreatments have been reported yet. METHODS/DESIGN: The planned study is a prospective multicenter, two-arm parallel group, randomized controlled clinical trial comparing selective and stepwise excavation in deciduous molars with deep, active caries lesions without pulpal symptoms. We will recruit 300 children aged between three and nine-years-old with a minimum of one such molar. Patients participating in another study, or those with systemic diseases, disabilities or known allergies to used materials as well patients with teeth expected to exfoliate within the next 18 months will be excluded. After inclusion, sequence generation will be performed. Initial treatment will follow dental routine. During excavation, leathery, moist and reasonably soft dentin will be left in proximity to the pulp followed by adhesive restoration of the cavity. Afterwards, patients', dentists' and parents' subjective assessment of the treatment will be recorded using visual analogue or Likert scales. Re-examination will be performed after six months, and only then teeth will be allocated to one of the two interventions. Selectively excavated teeth will not be treated further, whilst for stepwise caries removal, a second excavation will be performed until only hard dentin remains. Clinical re-evaluations will be performed after 12, 24 and 36 months. Restorations will be reassessed using modified Ryge criteria. Objectively or subjectively required retreatments will determine success and survival. Retreatments will be evaluated both subjectively and regarding generated costs. DISCUSSION: Based on the results of the trial, decision-making for treating deep caries lesions in deciduous molars based on multiple criteria should be feasible. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT02232828 (registered on 29 November 2014).

LASP1 is a novel BCR-ABL substrate and a phosphorylation-dependent binding partner of CRKL in chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is characterized by a genomic translocation generating a permanently active BCR-ABL oncogene with a complex pattern of atypically tyrosine-phosphorylated proteins that drive the malignant phenotype of CML. Recently, the LIM and SH3 domain protein 1 (LASP1) was identified as a component of a six gene signature that is strongly predictive for disease progression and relapse in CML patients. However, the underlying mechanisms why LASP1 expression correlates with dismal outcome remained unresolved. Here, we identified LASP1 as a novel and overexpressed direct substrate of BCR-ABL in CML. We demonstrate that LASP1 is specifically phosphorylated by BCR-ABL at tyrosine-171 in CML patients, which is abolished by tyrosine kinase inhibitor therapy. Further studies revealed that LASP1 phosphorylation results in an association with CRKL - another specific BCR-ABL substrate and bona fide biomarker for BCR-ABL activity. pLASP1-Y171 binds to non-phosphorylated CRKL at its SH2 domain. Accordingly, the BCR-ABL-mediated pathophysiological hyper-phosphorylation of LASP1 in CML disrupts normal regulation of CRKL and LASP1, which likely has implications on downstream BCR-ABL signaling. Collectively, our results suggest that LASP1 phosphorylation might serve as an additional candidate biomarker for assessment of BCR-ABL activity and provide a first step toward a molecular understanding of LASP1 function in CML.