Novel second-generation rexinoid induces growth arrest and reduces cancer cell stemness in human neuroblastoma patient-derived xenografts

IntroductionThe poor therapeutic efficacy seen with current treatments for neuroblastoma may be attributed to stem cell-like cancer cells (SCLCCs), a subpopulation of cancer cells associated with poor prognosis and disease recurrence. Retinoic acid (RA) is a differentiating agent used as maintenance therapy for high-risk neuroblastoma but nearly half of children treated with RA relapse. We hypothesized that 6-Methyl-UAB30 (6-Me), a second-generation rexinoid recently developed with a favorable toxicity profile compared to RA, would reduce cancer cell stemness in human neuroblastoma patient-derived xenografts (PDXs).MethodsCells from three neuroblastoma PDXs were treated with 6-Me and proliferation, viability, motility, and cell-cycle progression were assessed. CD133 expression, sphere formation, and mRNA abundance of stemness and differentiation markers were evaluated using flow cytometry, in vitro extreme limiting dilution analysis, and real-time PCR, respectively.ResultsTreatment with 6-Me decreased proliferation, viability, and motility, and induced cell-cycle arrest and differentiation in all three neuroblastoma PDXs. In addition, 6-Me treatment led to decreased CD133 expression, decreased sphere-forming ability, and decreased mRNA abundance of Oct4, Nanog, and Sox2, indicating decreased cancer cell stemness.Conclusions6-Me decreased oncogenicity and reduced cancer cell stemness of neuroblastoma PDXs, warranting further exploration of 6-Me as potential novel therapy for neuroblastoma.     

Tissue microarray: an effective high-throughput method to study the placenta for clinical and research purposes.

OBJECTIVE: Tissue microarray (TMA) technology allows simultaneous examination of the expression of many molecular markers (protein, mRNA, DNA, etc.) with high-throughput. The application of this technology, to date, has been largely confined to the study of cancer. Placental pathology poses unique challenges because of the size of the organ, its complex anatomy, as well as its histological heterogeneity. The objective of this study was to assess the feasibility and efficiency of TMAs for immunohistochemistry and in situ hybridization of placental tissues. STUDY DESIGN: TMAs were constructed using an automated tissue arrayer. Standard 0.6-mm or 1-mm microarray needles were used. Villous parenchyma, basal plate, and chorioamniotic membranes were targeted in each block. Five mum-thick TMA sections underwent immunohistochemical analysis of both cytoplasmic and nuclear antigens using a panel of antibodies against a variety of cytoplasmic [cytokeratin-7, vascular endothelial growth factor (VEGF), and protein Z], membranous (endoglin), and nuclear (c-fos and c-jun) antigens. mRNA in situ hybridization for surfactant protein A (SP-A) and chromogenic in situ hybridization for the Y chromosome (DYZ1) were also performed. RESULTS: Validation of TMA immunoreactivity demonstrated comparable results with corresponding whole sections. When a two-tiered scoring system (positive/negative) was employed, there was agreement between two and three cores and whole tissue sections (kappa>0.7). When a three-tiered scoring system (negative, weak-positive, or strong-positive) was used, the data from three cores showed the highest agreement with whole tissue sections (kappa >0.7). In situ hybridization experiments for mRNA and DNA were also successful in that the signals were readily detectable. Successful transfer from the donor block to the recipient block differed according to the anatomical compartment. The transfer efficiency of villous parenchyma, basal plate, and chorioamniotic membranes were 96.9% (875/903), 76.7% (115/150), and 75.4% (224/297), respectively. CONCLUSION: TMA is a practical and effective tool for high-throughput molecular analysis of the human placenta. Duplicate and triplicate cores offer agreement with whole tissue sections for two-category distinction immunostaining. TMA also affords relevant results from in situ hybridization experiments for mRNA and DNA. The major advantages are the conservation of tissues and reagents, simultaneous comparison of molecular markers in different anatomical compartments of the placenta, and reduction of experimental error.     

Size-Dependent Persistent Luminescence of YAGG:Cr3+ Nanophosphors

In the current work, YAGG:Cr³⁺ nanophosphors were synthesized by the Pechini method and then annealed at different temperatures in the range 800–1300 °C. The structure and morphology of the samples were characterized by X-ray Powder Diffraction (XRPD). The lattice parameters and average crystalline sizes as site occupation by Al³⁺ and Ga³⁺ ions were calculated from the Rietveld refinement data. To investigate the effect of crystalline size of the materials on their optical properties: excitation and emission spectra were recorded and analyzed. Finally, the effect of crystalline size on the probability of carrier recombination leading to PersL was determined experimentally with thermoluminescence analyses. The T_max-T_stop method was applied to determine the trap type and particle size (calcination temperature) effect on their redistribution. A correlation between structural changes and trap redistribution was found. In particular, the extinction of high-temperature TL maximum with increasing annealing temperatures is observed, while low-temperature TL maximum increases and reaches a maximum when the lattice parameter reaches saturation.     

CD133 identifies perivascular niches in grade II–IV astrocytomas

The aim of the present study was to investigate the localization and distribution of the putative brain tumour stem cell marker CD133 in formalin fixed paraffin embedded astrocytomas. A retrospective analysis of 114 grade II, III and IV astrocytomas was undertaken. The immunohistochemical expression of CD133 in paraffin sections was analysed using morphometry. In all grades, CD133 was expressed on tumour and endothelial cells. Tumour cells were found in perivascular niches, as dispersed single cells and in pseudopalisade formations around necrosis. There was no correlation between the mean volume fraction of CD133⁺ niches and all CD133⁺ tumour cells and tumour grade. However, the volume fraction of CD133⁺ blood vessels increased significantly from 0.4% in diffuse astrocytomas to 2.2% in glioblastomas. Neither of them was related to patient survival. Double immunofluorescence stainings showed that the CD133⁺ niches both contained CD133⁺ cells with and without co-expression of the intermediate filament protein marker nestin, and only few CD133⁺/MIB-1⁺ proliferating cells were found. In conclusion, a CD133⁺ perivascular stem cell-like entity exists in astrocytomas. CD133⁺ tumour vessels may play an important role in a brain tumour stem cell context, while CD133 alone does not appear to be a specific tumour stem cell marker related to patient survival.     

Use of phytotherapy in dentistry

Over the past decade, interest in drugs derived from medicinal plants has markedly increased. This study was aimed at a literature review focusing on studies investigating herbal drugs and other natural products, as well as their therapeutic application, side effects and possible drug interactions. Few studies were found to support their rational use in dentistry. Since there is an increasing use of phytotherapeutic agents in dentistry, further studies are needed to evaluate their safety and effectiveness for clinical use.     

Is present pharmacy education adapted to needs? Survey results from young practitioner views regarding pharmacy education outcome towards a national reform in Hungary

BackgroundThe pharmacist career is constantly adapting to societal and health care needs. The past decade has seen a growing demand for curricular development to align graduation outcome with workforce competencies.ObjectiveThis study aims to identify expectations for both didactic and experiential components of a new curriculum based on young pharmacist practitioner views.MethodsAn online survey questionnaire was used in 2019–2020 to evaluate the pharmacy curriculum to detect indicators or key areas which require comprehensive reform.ResultsThe predominant majority of the 205 study participants recommended reduction in credit hours for Natural Sciences (78.54%) and a similar increase in the Theoretical and Practical Expertise Module (77.9%). Pharmaceutical care, clinical therapeutics and clinical pharmacy competencies should also be more highlighted in the program. Findings indicate the current training does not prepare for problem-solving and daily workplace challenges (72.7%) or for extended pharmacist skills and competencies (71.71%). Results show inconsistency in practical training experience, as all respondents participated in practical training for drug manufacturing and analysis but 61.0% reported no hands-on skills training in a hospital-clinical simulation setting. Indications for practitioner involvement into the natural sciences and biomedical subjects (86.3%) confirm the obvious need for more practice-oriented education.ConclusionsEducational reforms seem to be inevitable to achieve measurable improvement in professional practice and skills competency. The country specific demand for a needs-based pharmacy education reflects global trends but may also provide useful insights for individual transitions to transform education through practice and improve practice through education.     

Behavioural insights and the evolving COVID-19 pandemic

Behavioural sciences have complemented medical and epidemiological sciences in the response to the SARS-CoV-2 pandemic. As vaccination uptake continues to increase across the EU/EEA – including booster vaccinations – behavioural science research remains important for both pandemic policy, planning of services and communication. From a behavioural perspective, the following three areas are key as the pandemic progresses: (i) attaining and maintaining high levels of vaccination including booster doses across all groups in society, including socially vulnerable populations, (ii) informing sustainable pandemic policies and ensuring adherence to basic prevention measures to protect the most vulnerable population, and (iii) facilitating population preparedness and willingness to support and adhere to the reimposition of restrictions locally or regionally whenever outbreaks may occur. Based on mixed-methods research, expert consultations, and engagement with communities, behavioural data and interventions can thus be important to prevent and effectively respond to local or regional outbreaks, and to minimise socioeconomic and health disparities. In this Perspective, we briefly outline these topics from a European viewpoint, while recognising the importance of considering the specific context in individual countries.     

GP strategies to avoid imaging overuse. A qualitative study in Norwegian general practice

ObjectivesThe aim of the study was to identify general practitioners’ (GPs) strategies to avoid unnecessary diagnostic imaging when encountering patients with such expectations and to explore how patients experience these strategies.Design, setting and subjectsWe conducted a qualitative study that combined observations of consultations and interviews with GPs and patients. A total of 24 patients visiting nine different GPs in two Norwegian urban areas were included in the study. Of these, 12 consultations were considered suitable for studying GP strategies and were therefore selected for a more thorough analysis.Main outcome measuresGPs’ communication strategies to avoid unnecessary medical imaging and patients’ experiences with such strategies.ResultsFive categories of strategies were identified: (1) wait and see – or suggest an alternative; (2) the art of rejection; (3) seek support from a professional authority; (4) partnership and shared decision-making and (5) reassurance, normalisation and recognition. The GPs often used multiple strategies. Factors related to a long-term doctor–patient relationship seemed to influence both communication and how both parties experienced the decision. Three important factors were evident: the patient trusted the doctor, the doctor knew the patient’s medical history and the doctor knew the patient as a person. The patients seemed to be generally satisfied with the outcomes of the consultations.ConclusionGPs largely combine different strategies when meeting patients’ expectations of diagnostic imaging that are not strictly medically indicated. Continuity of the doctor–patient relationship with good personal knowledge and trust between doctor and patient appeared crucial for patients to accept the doctors'' decisions.

Key points

• GPs usually combine a broad range of strategies to avoid unnecessary medical imaging
• The patients appeared generally satisfied regardless of the strategy the strategy used by the GPs and even where their referral request were rejected
• Factors related to a long-term doctor–patient relationship appeared decisive