Influence of the punch diameter and curvature on the yield pressure of MCC-compacts during Heckel analysis.

The volume reduction behaviour of powders has been quantified by means of the 'in-die' yield pressure (YP) using Heckel analysis. However, because different YPs are reported for the same material, the experimental conditions influencing this material-constant were investigated. Silicified microcrystalline cellulose was compressed into flat-faced and convex tablets using a compaction simulator instrumented with load and displacement transducers. During compression, upper and lower punch force and displacement data were recorded and corrected for punch deformation. A symmetrical triangle wave compression profile was used and the instantaneous punch velocity was kept constant (5mm/s). Individual tablet height and weight were used for Heckel analysis. The influence of the 'effective compression pressure' (P(EFF)) (ranging from 10 to 350 MPa), punch diameter (PD) (4, 9.5 and 12 mm) and filling depth (FD) (4.5, 7.5 and 10.5mm) on YP was statistically evaluated using Response Surface Modelling software. A quadratic surface response equation, describing the relationship between P(EFF), PD, FD and YP, was proposed for concave (Adj R(2): 0.8424; S.D.: 14.60 MPa) and flat-faced (Adj R(2): 0.8409; S.D.: 4.49 MPa) punches. YP and tensile strength were mainly determined by P(EFF), irrespective of punch curvature. FD and PD had only a minor influence on the YP, although more pronounced for the concave punches. The method used resulted in reproducible P(EFF) and tensile strength values and the flat-faced tablets showed less weight variation. Flat-faced punches are preferred over punches with a concave surface when investigating the volume reduction behaviour of a powder by means of Heckel analysis and the experimental parameters should be reported.     

“Rehabilitation Research Framework for Patients With COVID-19” Defined by Cochrane Rehabilitation and the World Health Organization Rehabilitation Programme

The coronavirus disease 2019 (COVID-19) pandemic resulted in a surge of research activity. Since its outset, efforts have been made to guide the rapid generation of research in medicine. There are gaps in some areas of rehabilitation research for patients with COVID-19. The development of a specific research framework might serve to help monitor the status of research (mapping), shape and strengthen research by pointing to under-investigated areas, and promote rehabilitation research in this context. This article introduces and discusses the COVID-19 Rehabilitation Research Framework (CRRF) and presents the methodology used for its development.The questions have been developed among the World Health Organization (WHO) Rehabilitation Programme, Cochrane Rehabilitation, and the experts of its Rehabilitation–COVID-19 Evidence-based Response Action International Multiprofessional Steering Committee. The framework is divided into 2 parts and includes 20 questions organized in 4 groups: epidemiology, and evidence at the micro- (individual), meso- (health services), and macro- (health systems) levels.The CRRF offers a comprehensive view of the research areas relevant to COVID-19 and rehabilitation that are necessary to inform best practice and ensure rehabilitation services and health systems can best serve the population with COVID-19. The collaboration between Cochrane Rehabilitation and the WHO Rehabilitation Programme in establishing the CRRF brought together perspectives from the health systems, health management, and clinical evidence. The authors encourage researchers to use the CRRF when planning studies on rehabilitation in the context of COVID-19.     

A review and evaluation of patient-reported outcome measures for spasticity in persons with spinal cord damage: Recommendations from the Ability Network – an international initiative

Context: Patient-reported outcome measures (PROMs) are valuable for capturing the impact of spasticity on health-related quality of life (HRQoL) in persons with spinal cord damage (SCD) and evaluating the efficacy of interventions.Objective: To provide practical guidance for measuring HRQoL in persons with spasticity following SCD.Methods: Literature reviews identified measures of HRQoL and caregiver burden, utilized in studies addressing spasticity in SCD. Identified measures were evaluated for clinical relevance and practicality for use in clinical practice and research. The PRISM, SCI-SET, EQ-5D and SF-36 instruments were mapped to the International Classification of Functioning, Disability and Health (ICF). The PRISM and SCI-SET were evaluated using the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) checklist.Results: Two spasticity-specific, five generic, and four preference-based measures were identified. ICF mapping and the COSMIN checklist supported the use of the PRISM and SCI-SET in SCD. The SF-36 is considered the most useful generic measure; disability-adapted versions may be more acceptable but further studies on psychometric properties are required. The SF-36 can be converted to a preference-based measure (SF-6D), or alternatively the EQ-5D can be used. While no measures specific to caregivers of people with SCD were identified, the Caregiver Burden Scale and the Zarit Burden Interview are considered suitable.Conclusion: Recommended measures include the PRISM and SCI-SET (condition-specific), SF-36 (generic), and Caregiver Burden Scale and Zarit Burden Interview (caregiver burden). Consideration should be given to using condition-specific and generic measures in combination; the PRISM or SCI-SET combined with SF-36 is recommended.     

A validated HPLC method for the determination of thiazinamium methylsulphate in pharmaceutical preparations

The phenothiazine derivative thiazinamium methylsulphate is a drug with antihistaminic and anticholinergic properties, often used in some types of obstructive lung diseases. Because there is a lack of chromatographic data available for its determination, the objective of the present investigation was to develop a sensitive and rapid HPLC method for the quantitative estimation of thiazinamium methylsulphate in a pharmaceutical dosage form, applicable to routine analysis. The drug was chromatographed on a C18-reversed phase system applying a Licrocart column (LiChrospher 100 RP 18, 125 x 4 mm) with a mobile phase consisting of acetonitrile-water (3:7, v/v), employing as ion-pairing agent octanesulphonic acid sodium salt (20 mM) together with N,N-dimethyloctylamine (20 mM), adjusted to pH 3. Detection occurred at 254 nm. Propylparaben was used as an internal standard. The method was applied to solutions for intramuscular injection containing thiazinamium methylsulphate (65 mg/2 ml). Since little sample preparation is required, most analyses can be carried out within 15 min. The optimized method was validated and provided acceptable results with respect to linearity (r = 0.9999), precision and accuracy in the concentration range of 26-78 microg/ml. The proposed method is presently employed to investigate the stability of thiazinamium methylsulphate in solutions for intramuscular injection in the presence of anti-oxidizing agents.     

A special case on the use of ultrasonography for evaluation of the spinal canal and its contents in adults

In this article we present a 70-year-old man with a history of severe trauma in the upper thoracic spine. This patient presented at our emergency department with a leaking wound in the lower neck after removal of osteosynthetic material. He had undergone a laminectomy of the third thoracic vertebra in the past. As an incidental finding, while examining the region of the lower neck by transcutaneous ultrasonography, we diagnosed a post-traumatic syrinx of the spinal medulla at this level.