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1.
This paper proposes a ‘valuographic’ approach to diagnosis, exploring how values and valuation practices are implicated in the contested diagnostic category of idiopathic short stature (ISS). ISS describes children who are ‘abnormally’ short but do not have any other detectable pathology. In the USA growth‐promoting hormone therapy has been approved for ISS children, since 2003. However, no other jurisdiction has approved this treatment and the value of ISS as a diagnostic category remains disputed among healthcare professionals. Drawing on qualitative interviews with paediatric endocrinologists in the UK and the US, this study presents a historical snapshot illustrating how the problematisation of ISS as a diagnosis involved multiple registers of value including epistemic, economic and moral calculations of worth. Contestation of the diagnosis was not just about what counts but about what ought to be counted, as respondents’ accounts of ISS gave differential weight to a range of types of evidence and methods of assessment. Ultimately what was at stake was not just the value of increased height for short patients, but what it meant to properly practice paediatric endocrinology. Consideration is then given to how a valuographic approach can be applied to sociological studies of diagnosis more broadly.  相似文献   
2.
Although combined spin‐ and gradient‐echo (SAGE) dynamic susceptibility‐contrast (DSC) MRI can provide perfusion quantification that is sensitive to both macrovessels and microvessels while correcting for T1‐shortening effects, spatial coverage is often limited in order to maintain a high temporal resolution for DSC quantification. In this work, we combined a SAGE echo‐planar imaging (EPI) sequence with simultaneous multi‐slice (SMS) excitation and blipped controlled aliasing in parallel imaging (blipped CAIPI) at 3 T to achieve both high temporal resolution and whole brain coverage. Two protocols using this sequence with multi‐band (MB) acceleration factors of 2 and 3 were evaluated in 20 patients with treated gliomas to determine the optimal scan parameters for clinical use. ΔR2*(t) and ΔR2(t) curves were derived to calculate dynamic signal‐to‐noise ratio (dSNR), ΔR2*‐ and ΔR2‐based relative cerebral blood volume (rCBV), and mean vessel diameter (mVD) for each voxel. The resulting SAGE DSC images acquired using MB acceleration of 3 versus 2 appeared visually similar in terms of image distortion and contrast. The difference in the mean dSNR from normal‐appearing white matter (NAWM) and that in the mean dSNR between NAWM and normal‐appearing gray matter were not statistically significant between the two protocols. ΔR2*‐ and ΔR2‐rCBV maps and mVD maps provided unique contrast and spatial heterogeneity within tumors.  相似文献   
3.
A major evolution in the treatment of patients with diffuse large B-cell lymphoma (DLBCL) occurred almost two decades ago, with clinical trials demonstrating that the addition of rituximab (R) to cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP), which had been the “gold standard” of therapy since 1976, significantly improved outcome, including response rate and disease-free survival, of these patients. Since the adoption of R-CHOP, subsequent clinical trials have attempted to improve upon outcomes achieved with R-CHOP, with a variety of approaches examined. These have included dose intensification, which may be applicable in younger patients, but not in the many older or frailer patients with a disease with median age at diagnosis in the 60's. Newer anti-CD20 monoclonal antibodies have been substituted for rituximab in frontline regimens. A series of new agents, with unique mechanisms of action, have been added to the R-CHOP backbone. Rituximab-based, non-anthracycline regimens have been studied for older, more frail patients. The utility of maintenance therapy in responding patients has been re-examined, despite the lack of benefit found in the US Intergroup trial. Advances in molecular and genetic aspects of DLBCL have emerged since the seminal R-CHOP trials, demonstrating the DLBCL is not a single entity, but instead a spectrum of multiple disease subtypes. Attempts have been made to identify those patients at baseline who have poorer outcomes with standard approaches, utilizing laboratory and imaging findings. Moving forward, different risk-adapted treatment approaches will be studied to in an effort to improve overall outcome beyond R-CHOP.  相似文献   
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Highly purified cannabidiol (CBD) has demonstrated efficacy with an acceptable safety profile in patients with Lennox-Gastaut syndrome or Dravet syndrome in randomized, double-blind, add-on, controlled phase 3 trials. It is important to consider the possibility of drug-drug interactions (DDIs). Here, we review six trials of CBD (Epidiolex/Epidyolex; 100 mg/mL oral solution) in healthy volunteers or patients with epilepsy, which investigated potential interactions between CBD and enzymes involved in drug metabolism of common antiseizure drugs (ASDs). CBD did not affect CYP3A4 activity. Induction of CYP3A4 and CYP2C19 led to small reductions in exposure to CBD and its major metabolites. Inhibition of CYP3A4 activity did not affect CBD exposure and caused small increases in exposure to CBD metabolites. Inhibition of CYP2C19 activity led to a small increase in exposure to CBD and small decreases in exposure to CBD metabolites. One potentially clinically important DDI was identified: combination of CBD and clobazam (CLB) did not affect CBD or CLB exposure, but increased exposure to major metabolites of both compounds. Reduction of CLB dose may be considered if adverse reactions known to occur with CLB are experienced when it is coadministered with CBD. There was a small increase of exposure to stiripentol (STP) when coadministered with CBD. STP had no effect on CBD exposure but led to minor decreases in exposure to CBD metabolites. Combination of CBD and valproate (VPA) did not cause clinically important changes in the pharmacokinetics of either drug, or 2-propyl-4-pentenoic acid. Concomitant VPA caused small increases in exposure to CBD metabolites. Dose adjustments are not likely to be necessary when CBD is combined with STP or VPA. The safety results from these trials were consistent with the known safety profile of CBD. These trials indicate an overall low potential for DDIs between CBD and other ASDs, except for CLB.  相似文献   
7.
Understanding the contribution of endothelial cells to the progenitor pools of adult tissues has the potential to inform therapies for human disease.To address whether endothelial cells transdifferentiate into non-vascular cell types,we performed cell lineage tracing analysis using transgenic mice engineered to express a fluorescent marker following activation by tamoxifen in vascular endothelial cadherin promoter-expressing cells(VEcad-CreERT2;B6 Cg-Gt(ROSA)26Sortm9(CAG-tdTomato)Hze).Activation of target-cell labeling following 1.5 months of ad libitum feeding with tamoxifen-laden chow in 4–5 month-old mice resulted in the tracing of central nervous system and peripheral cells that include:cerebellar granule neurons,ependymal cells,skeletal myocytes,pancreatic beta cells,pancreatic acinar cells,tubular cells in the renal cortex,duodenal crypt cells,ileal crypt cells,and hair follicle stem cells.As Nestin expression has been reported in a subset of endothelial cells,Nes-CreERT2 mice were also utilized in these conditions.The tracing of cells in adult Nes-CreERT2 mice revealed the labeling of canonical progeny cell types such as hippocampal and olfactory granule neurons as well as ependymal cells.Interestingly,Nestin tracing also labeled skeletal myocytes,ileal crypt cells,and sparsely marked cerebellar granule neurons.Our findings provide support for endothelial cells as active contributors to adult tissue progenitor pools.This information could be of particular significance for the intravenous delivery of therapeutics to downstream endothelial-derived cellular targets.The animal experiments were approved by the Boise State University Institute Animal Care and Use Committee(approval No.006-AC15-018)on October 31,2018.  相似文献   
8.
Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms which account for less than 1% of all gastrointestinal malignancies. Of all the extra-abdominal metastases of GIST, superficial soft tissue metastases are the rarest. Previous reports have found success with sunitinib in imatinib-resistant GIST, but we report a certain wild-type KIT mutation GIST with cutaneous and subcutaneous metastasis that was unresponsive to multiple tyrosine kinase inhibitor (TKI) treatments. This case illustrates that knowing the specific type of KIT mutations may uncover resistance of certain GIST's to TKIs, necessitating more targeted and alternative therapy.  相似文献   
9.

Objective

Adverse events which result from medication errors are considered to be one of the most frequently encountered patient safety issues in clinical settings. We undertook a qualitative investigation to identify and explore factors relating to medication error in an adult oncology department in Saudi Arabia from the perspective of healthcare professionals.

Methods

This was a qualitative study conducted in an adult oncology department in Saudi Arabia. After obtaining required ethical approvals and written consents from the participants, semi-structured interviews and focus group discussions were carried out for data collection. A stratified purposive sampling strategy was used to recruit medical doctors, pharmacists, and nurses. NVivo Pro version 11 was used for data analyses. Inductive thematic analysis was adopted in the primary coding of data while secondary coding of data was carried out deductively applying the Hospital Survey of Patient Safety Culture (HSOPSC) framework.

Result

The total number of participants were 38. Majority of the participants were nurses (n?=?24), females (n?=?30), and not of Saudi nationality (n?=?31) with an average age of 36?years old. Causes of medication errors were categorized into 6 themes. These causes were related teamwork across units, staffing, handover of medication related information, accepted behavioural norms, frequency of events reported, and non-punitive response to error.

Conclusion

There were numerous causes for medication errors in the adult oncology department. This means substantive improvement in medication safety is likely to require multiple, inter-relating, complex interventions. More research should be conducted to examine context-specific interventions that may have the potential to improve medication safety in this and similar departments.  相似文献   
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