Efficacy of an Intensive Exposure Intervention for Individuals With Persistent Concussion Symptoms Following Concussion: A Concurrent Multiple Baseline Single-Case Experimental Design (SCED) Study.

OBJECTIVE: After a concussion, 1 in 3 patients report persistent symptoms and experience long-term consequences interfering with daily functioning, known as persistent concussion symptoms (PCS). Evidence suggests PCS is (partly) maintained by anxious thoughts about brain functioning, recovery, and experienced symptoms, leading to avoidance behaviors, which may prevent patients from meeting life demands. We aimed to investigate the efficacy of a newly developed intensive exposure intervention for individuals with PCS after concussion aimed to tackle avoidance behavior. SETTING: Participants took part in the intervention at the Maastricht University faculty. PARTICIPANTS: Four participants who experienced PCS after concussion partook in the exploratory study. Participants' age ranged between 20 and 32 (mean = 26.5, SD = 5.9) years, with an average length of time after the concussion of 9.8 months. DESIGN: A concurrent multiple-baseline single-case design was conducted. The baseline period (A phase) length was randomly determined across participants (3, 4, 5, or 6 weeks). The exposure intervention (B phase) was conducted by psychologists over a 4-week period and consisted of 3 stages: exploration (2 sessions), active exposure (12 sessions conducted over 1 week), and 2 booster sessions. MAIN MEASURES: Participants answered daily questions on a visual analog scale related to symptom experience, satisfaction with daily functioning, and degree of avoidance of feared activities. Additional outcomes included symptom severity, catastrophizing, fear of mental activity, anxiety, depression, and societal participation. RESULTS: Tau-U yielded significant effects (P < .05) for all participants on all measures when comparing baseline and intervention phases. The pooled standardized mean difference was high for all measures (symptom experience = 0.93, satisfaction of daily functioning = 1.86, and activity avoidance = -2.05). CONCLUSIONS: The results show efficacy of the newly developed intensive exposure treatment for PCS after concussion, which is based on the fear avoidance model. Replication in a larger heterogeneous sample is warranted and needed.

Electrocatalytic H2 Evolution by Supramolecular Ru(II)-Rh(III)-Ru(II) Complexes: Importance of Ligands as Electron Reservoirs and Speciation upon Reduction.

The supramolecular water reduction photocatalysts [{(Ph2phen)2Ru(dpp)}2RhX2](PF6)5 (Ph2phen = 4,7-diphenyl-1,10-phenanthroline, dpp =2,3-bis(2-pyridyl)pyrazine X = Cl, Br) are efficient electrocatalysts for the reduction of CF3SO3H, CF3CO2H, and CH3CO2H to H2 in DMF or DMF/H2O mixtures. The onset of catalytic current occurs at -0.82 V versus Ag/AgCl for CF3SO3H, -0.90 V for CF3CO2H, and -1.1 V for CH3CO2H with overpotentials of 0.61, 0.45, and 0.10 V, respectively. In each case, catalysis is triggered by the first dpp ligand reduction implicating the dpp as an electron reservoir in catalysis. A new species with Epc ∼ -0.75 V was observed in the presence of stoichiometric amounts of strong acid, and its identity is proposed as the Rh(H)(III/II) redox couple. H2 was produced in 72-85% Faradaic yields and 95-116 turnovers after 2 h and 435 turnovers after 10 h of bulk electrolysis. The identities of Rh(I) species upon reduction have been studied. In contrast to the expected dissociation of halides in the Rh(I) state, the halide loss depends on solvent and water content. In dry CH3CN, in which Cl(-) is poorly solvated, a [Ru] complex dissociates and [(Ph2phen)2Ru(dpp)Rh(I)Cl2](+) and [(Ph2phen)2Ru(dpp)](2+) are formed. In contrast, for X = Br(-), the major product of reduction is the intact trimetallic Rh(I) complex [{(Ph2phen)2Ru(dpp)}2Rh(I)](5+). Chloride loss in CH3CN is facilitated by addition of 3 M H2O. In DMF, the reduced species is [{(Ph2phen)2Ru(dpp)}2Rh(I)](5+) regardless of X = Cl(-) or Br(-).

Psychometric properties of two instruments assessing catastrophizing and fear-avoidance behavior in mild traumatic brain injury.

OBJECTIVE: Psychometrically sound measures of catastrophizing about symptoms and fear avoidance behavior are needed to further applications of the fear-avoidance model in mild traumatic brain injury (mTBI) for research and clinical purposes. To this end, two questionnaires were adapted (minor), the Postconcussion Symptom Catastrophizing Scale (PCS-CS) and the Fear of Mental Activity Scale (FMA). This study aimed to investigate the factor structure, internal consistency, test-retest reliability, and concurrent and construct validity of two adapted questionnaires in a sample of participants with mTBI compared to participants with orthopedic injury and healthy adults. METHOD: One hundred eighty-five mTBI participants (40% female), 180 participants with orthopedic injury (55% female), and 116 healthy adults (55% female) participated in the study. All participants were assessed at two time points (2 weeks postinjury and 3 months) using self-reported questionnaires. Data were collected using online questionnaires. RESULTS: Findings indicated a three-factor model (magnification, rumination, helplessness) with a higher order factor (catastrophizing) for the PCS-CS and a two-factor model (activity avoidance and somatic focus) for the FMA. The results showed strong internal consistency, good test-retest reliability, and good concurrent and convergent validity for the PCS-CS and FMA across all samples. CONCLUSIONS: This study has shown that the PCS-CS and FMA are psychometrically sound instruments and can be considered for valid and reliable assessment of catastrophizing about postconcussion like symptoms and fear-avoidance beliefs about mental activities. These instruments can be used in research and clinical practice applications of the fear-avoidance model and add to explanations of prolonged recovery after mTBI. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Gastrointestinal bleeding secondary to trimethoprim-sulfamethoxazole-induced vitamin K deficiency.

There is a well-known association between vitamin K deficiency and haemorrhagic events including gastrointestinal bleeding. There is also a well-known association between both poor dietary intake of vitamin K and chronic antibiotic use and the development of vitamin K deficiency. Although the medical literature notes that cephalosporin antibiotics have a propensity to cause vitamin K deficiency due to the molecular structure of the medications and their ability to suppress the synthesis of clotting factors, there are other antibiotics that have also been implicated in the development of vitamin K deficiency. There are very few reports of trimethoprim/sulfamethoxazole causing vitamin K deficiency and further leading to bleeding episodes. We present such a case and discuss the risk factors leading to such complications.