Use of bilayer matrix wound dressing in the exenterated socket

To describe the novel use of a bilayer dermal substitute to reconstruct exenterated orbits. A retrospective chart review was performed in the practices of two surgeons (RET and PDL) of all patients who had undergone orbital exenteration between April 2014 and June 2016 and whose subsequent reconstruction included lining the socket with Integra bilayer. Patient demographics, pathologic diagnoses, surgical and post-operative complications, graft integrity, and patient acceptance were recorded. The charts of 7 patients (4 men and 3 women, ages 60–87 years) were reviewed. In all cases, the Integra graft had taken well to the socket bed at the time of silicone removal 3-4 weeks after surgery. Epithelialization of the socket occurred rapidly over the Integra graft (within several weeks) without incident in each case and with minimal postoperative management. No intraoperative or postoperative complications were noted. Integra dermal substitute is an ideal graft for the lining of an exenterated orbit. It is readily available in large quantities, handles easily, lines the socket smoothly, epithelializes rapidly, and requires minimal postoperative care. It offers minimal morbidity compared to skin grafting or free flap reconstruction, but greatly speeds epithelialization compared to laissez faire management. Surgeons should consider reconstructing exenterated orbits with the Integra matrix, both for its ease of use and its ability to epithelialize rapidly.     

Birth prevalence and characteristics of congenital toxoplasmosis in Sergipe,North‐east Brazil

Objectives To estimate, by neonatal screening, the birth prevalence of congenital toxoplasmosis among live‐born infants in Sergipe state, Brazil, and to investigate the clinical features of affected infants. Methods Dried blood spot specimens obtained from 15 204 neonates were assayed for the presence of anti‐T. gondii IgM antibodies. Duplicate retesting was done in infants with positive and borderline results. Confirmatory testing in peripheral blood samples consisted of testing for anti‐T. gondii IgG and IgM in infants and mothers. Those with possible congenital toxoplasmosis were evaluated and followed up to a median age of 20 months. Congenital infection was confirmed in the presence of persisting anti‐T. gondii IgG antibodies beyond 12 months of age. All infants with confirmed infection were treated with pyrimethamine, sulfadiazine and folinic acid for 1 year. Results Fifty‐three infants had detectable IgM in dried blood spot specimens. Confirmatory testing was reactive in 39/50, of which, 38 completed follow‐up. Six of 15 204 newborns were diagnosed with congenital toxoplasmosis, resulting in an estimated birth prevalence of four per 10 000 [CI 95% 1.4–8.0]. Four infants (67%) showed signs of congenital toxoplasmosis in their first year of life; three (75%) had retinochoroidal scars, and one had cerebral calcifications. Two infants remained asymptomatic until 20 months of age. Conclusions The birth prevalence of congenital toxoplasmosis is high in the Brazilian state of Sergipe, with most of the infants showing ocular lesions. Preventive measures are strongly warranted.     

Long-Term Psychological Outcome of Workers After Occupational Injury: Prevalence and Risk Factors

Introduction This study aimed to examine the prevalence rates of both post-traumatic stress disorder (PTSD) and major depression at 12 months in workers experiencing different types of occupational injury in Taiwan. Demographic and injury-related risk factors for psychological symptoms were also evaluated. Methods Our study candidates were injured workers in Taiwan who were hospitalized for 3 days or longer and received hospitalization benefits from the Labor Insurance program. A two-staged survey study was conducted. A self-reported questionnaire including the Brief Symptom Rating Scale and Post-traumatic Symptom Checklist was sent to workers at 12 months after injury. Those who met the criteria were recruited for the second-stage phone interview with a psychiatrist using the Mini-international Neuropsychiatric Interview (MINI). Results A total of 1,233 workers completed the questionnaire (response rate 28.0 %). Among them, 167 (13.5 %) fulfilled the criteria for the MINI interview and were invited. A total of 106 (63.5 %) completed the phone interview. The estimated rate of either PTSD/PPTSD or major depression was 5.2 %. The risk factors for psychological symptoms were female gender, lower education level, loss of consciousness after occupational injury, injury affecting physical appearance, occupational injury experience before this event, life experience before and after this injury, length of hospital stay, self-rated injury severity, and percentage of income to the family. Conclusions These results showed that occupational injury can cause long-term psychological impact in workers. Key demographic and injury characteristics may enhance the identification of at-risk occupational injured workers who would benefit from targeted screening and early intervention efforts.     

Combining the ‘bottom up’ and ‘top down’ approaches in pharmacokinetic modelling: fitting PBPK models to observed clinical data

Pharmacokinetic models range from being entirely exploratory and empirical, to semi-mechanistic and ultimately complex physiologically based pharmacokinetic (PBPK) models. This choice is conditional on the modelling purpose as well as the amount and quality of the available data. The main advantage of PBPK models is that they can be used to extrapolate outside the studied population and experimental conditions. The trade-off for this advantage is a complex system of differential equations with a considerable number of model parameters. When these parameters cannot be informed from in vitro or in silico experiments they are usually optimized with respect to observed clinical data. Parameter estimation in complex models is a challenging task associated with many methodological issues which are discussed here with specific recommendations. Concepts such as structural and practical identifiability are described with regards to PBPK modelling and the value of experimental design and sensitivity analyses is sketched out. Parameter estimation approaches are discussed, while we also highlight the importance of not neglecting the covariance structure between model parameters and the uncertainty and population variability that is associated with them. Finally the possibility of using model order reduction techniques and minimal semi-mechanistic models that retain the physiological-mechanistic nature only in the parts of the model which are relevant to the desired modelling purpose is emphasized. Careful attention to all the above issues allows us to integrate successfully information from in vitro or in silico experiments together with information deriving from observed clinical data and develop mechanistically sound models with clinical relevance.     

Itching for an answer: A review of potential mechanisms of scalp itch in psoriasis

Scalp psoriatic itch is a common complaint and often poses a therapeutic challenge. The pathophysiology of this phenomenon is unclear. The unique anatomy of the scalp contains richly innervated hair follicles, abundant vasculature and perifollicular inflammatory cytokines which may all contribute to this common sensory complaint. The mast cell, in particular, is portrayed as one of the main itch conductors for its ability to trigger neurogenic inflammation, activate the peripheral hypothalamic‐pituitary‐adrenal‐axis, process and integrate itch signalling through its interactions with the scalp hair follicles. Herein, we explain and speculate upon potential mechanisms underlying itchy scalp psoriasis, involving interconnections between the neuroimmune, neurovascular and neuroendocrine systems. Many factors may play roles in itchy scalp psoriasis including the scalp hair structure, immune system, endocrine system, nervous system and vascular system. These may warrant further exploration as therapeutic targets that go beyond the application of mere anti‐inflammatory agents.