Permeability sets the linear path instability of buoyancy-driven disks

The prediction of trajectories of buoyancy-driven objects immersed in a viscous fluid is a key problem in fluid dynamics. Simple-shaped objects, such as disks, present a great variety of trajectories, ranging from zig-zag to tumbling and chaotic motions. Yet, similar studies are lacking when the object is permeable. We perform a linear stability analysis of the steady vertical path of a thin permeable disk, whose flow through the microstructure is modelled via a stress-jump model based on homogenization theory. The relative velocity of the flow associated with the vertical steady path presents a recirculation region detached from the body, which shrinks and eventually disappears as the disk becomes more permeable. In analogy with the solid disk, one non-oscillatory and several oscillatory modes are identified and found to destabilize the fluid-solid coupled system away from its straight trajectory. Permeability progressively filters out the wake dynamics in the instability of the steady vertical path. Modes dominated by wake oscillations are first stabilized, followed by those characterized by weaker, or absent, wake oscillations, in which the wake is typically a tilting induced by the disk inclined trajectory. For sufficiently large permeabilities, the disk first undergoes a non-oscillatory divergence instability, which is expected to lead to a steady oblique path with a constant disk inclination, in the nonlinear regime. A further permeability increase reduces the unstable range of all modes until quenching of all linear instabilities

Sublingual immunotherapy: administration, dosages, use

Allergen extracts for sublingual immunotherapy (SLIT) are currently marketed by several manufacturers, with administration schedules and amount of allergen(s) quite variable in the different products, although almost all are standardized biologically or immunologically. The allergen extracts for SLIT are available in two main pharmaceutical forms: solution to be delivered by drop-counters, pre-dosed actuators (mini-pumps) or disposable single-dose vials; tablets with appropriate composition that allows a slow (1-2 minutes) dissolution in the mouth in contact with saliva. In Europe, SLIT is prescribed in general for one or a few allergens, and mixtures are less used, though there is no immunological contraindication to give multiple allergens. SLIT traditionally involves a build-up phase and a maintenance phase with the top dose. The build-up phase has usually the duration of 4 - 6 weeks. The patient must start with the lowest concentration and gradually increase, using the different dosage preparations, until the maintenance dose is reached. Rush and ultra-rush inductions have been introduced, based on the safety profile of SLIT that is very favorable. For these reasons it has been suggested that an updosing phase maybe even not necessary. The no-updosing approach would result in a treatment that is more patient-friendly and convenient to manage. Indeed, the most recent randomized trials were performed with the no-updosing regimen and their results in term of safety were as favorable as the studies performed with the traditional updosing approach. The currently recommended duration of SLIT is comprised between 3 and 4 years depending on the clinical response in single patients

Physical exercise in major depression: Reducing the mortality gap while improving clinical outcomes

Major depression shortens life while the effectiveness of frontline treatments remains modest. Exercise has been shown to be effective both in reducing mortality and in treating symptoms of major depression, but it is still underutilized in clinical practice, possibly due to prevalent misperceptions. For instance, a common misperception is that exercise is beneficial for depression mostly because of its positive effects on the body (\u201cfrom the neck down\u201d), whereas its effectiveness in treating core features of depression (\u201cfrom the neck up\u201d) is underappreciated. Other long-held misperceptions are that patients suffering from depression will not engage in exercise even if physicians prescribe it, and that only vigorous exercise is effective. Lastly, a false assumption is that exercise may be more harmful than beneficial in old age, and therefore should only be recommended to younger patients. This narrative review summarizes relevant literature to address the aforementioned misperceptions and to provide practical recommendations for prescribing exercise to individuals with major depression

Italian intersociety consensus on management of long covid in children

Background: Two sequelae of pediatric COVID-19 have been identified, the multisystem inflammatory syndrome in children (MIS-C) and the long COVID. Long COVID is much less precisely defined and includes all the persistent or new clinical manifestations evidenced in subjects previously infected by SARS-CoV-2 beyond the period of the acute infection and that cannot be explained by an alternative diagnosis. In this Intersociety Consensus, present knowledge on pediatric long COVID as well as how to identify and manage children with long COVID are discussed. Main findings: Although the true prevalence of long COVID in pediatrics is not exactly determined, it seems appropriate to recommend evaluating the presence of symptoms suggestive of long COVID near the end of the acute phase of the disease, between 4 and 12 weeks from this. Long COVID in children and adolescents should be suspected in presence of persistent headache and fatigue, sleep disturbance, difficulty in concentrating, abdominal pain, myalgia or arthralgia. Persistent chest pain, stomach pain, diarrhea, heart palpitations, and skin lesions should be considered as possible symptoms of long COVID. It is recommended that the primary care pediatrician visits all subjects with a suspected or a proven diagnosis of SARS-CoV-2 infection after 4 weeks to check for the presence of symptoms of previously unknown disease. In any case, a further check-up by the primary care pediatrician should be scheduled 3 months after the diagnosis of SARS-CoV-2 infection to confirm normality or to address emerging problems. The subjects who present symptoms of any organic problem must undergo a thorough evaluation of the same, with a possible request for clinical, laboratory and / or radiological in-depth analysis in case of need. Children and adolescents with clear symptoms of mental stress will need to be followed up by existing local services for problems of this type. Conclusions: Pediatric long COVID is a relevant problem that involve a considerable proportion of children and adolescents. Prognosis of these cases is generally good as in most of them symptoms disappear spontaneously. The few children with significant medical problems should be early identified after the acute phase of the infection and adequately managed to assure complete resolution. A relevant psychological support for all the children during COVID-19 pandemic must be organized by health authorities and government that have to treat this as a public health issue

Clinical standards for the assessment, management, and rehabilitation of post-TB lung disease

BACKGROUND: Increasing evidence suggests that post-TB lung disease (PTLD) causes significant morbidity and mortality. The aim of these clinical standards is to provide guidance on the assessment and management of PTLD and the implementation of pulmonary rehabilitation (PR). METHODS: A panel of global experts in the field of TB care and PR was identified; 62 participated in a Delphi process. A 5-point Likert scale was used to score the initial ideas for standards and after several rounds of revision the document was approved (with 100% agreement). RESULTS: Five clinical standards were defined: Standard 1, to assess patients at the end of TB treatment for PTLD (with adaptation for children and specific settings/situations); Standard 2, to identify patients with PTLD for PR; Standard 3, tailoring the PR programme to patient needs and the local setting; Standard 4, to evaluate the effectiveness of PR; and Standard 5, to conduct education and counselling. Standard 6 addresses public health aspects of PTLD and outcomes due to PR. CONCLUSION: This is the first consensus-based set of Clinical Standards for PTLD. Our aim is to improve patient care and quality of life by guiding clinicians, programme managers and public health officers in planning and implementing adequate measures to assess and manage PTLD

Clinical spectrum time course in non-Asian patients positive for anti-MDA5 antibodies

Objectives: To define the clinical spectrum time-course and prognosis of non-Asian patients positive for anti-MDA5 antibodies. Methods: We conducted a multicentre, international, retrospective cohort study. Results: 149 anti-MDA5 positive patients (median onset age 53 years, median disease duration 18 months), mainly females (100, 67%), were included. Dermatomyositis (64, 43%) and amyopathic dermatomyositis (47, 31%), were the main diagnosis; 15 patients (10%) were classified as interstitial pneumonia with autoimmune features (IPAF) and 7 (5%) as rheumatoid arthritis. The main clinical findings observed were myositis (84, 56%), interstitial lung disease (ILD) (108, 78%), skin lesions (111, 74%), and arthritis (76, 51%). The onset of these manifestations was not concomitant in 74 cases (50%). Of note, 32 (21.5%) patients were admitted to the intensive care unit for rapidly progressive-ILD, which occurred in median 2 months from lung involvement detection, in the majority of cases (28, 19%) despite previous immunosuppressive treatment. One-third of patients (47, 32% each) was ANA and anti-ENA antibodies negative and a similar percentage was anti-Ro52 kDa antibodies positive. Non-specific interstitial pneumonia (65, 60%), organising pneumonia (23, 21%), and usual interstitial pneumonia-like pattern (14, 13%) were the main ILD patterns observed. Twenty-six patients died (17%), 19 (13%) had a rapidly progressive-ILD. Conclusions: The clinical spectrum of the anti-MDA5 antibodies-related disease is heterogeneous. Rapidly-progressive ILD deeply impacts the prognosis also in non-Asian patients, occurring early during the disease course. Anti-MDA5 antibody positivity should be considered even when baseline autoimmune screening is negative, anti-Ro52 kDa antibodies are positive, and radiology findings show a NSIP pattern

Influence of antisynthetase antibodies specificities on antisynthetase syndrome clinical spectrum time course

Antisynthetase syndrome (ASSD) is a rare clinical condition that is characterized by the occurrence of a classic clinical triad, encompassing myositis, arthritis, and interstitial lung disease (ILD), along with specific autoantibodies that are addressed to different aminoacyl tRNA synthetases (ARS). Until now, it has been unknown whether the presence of a different ARS might affect the clinical presentation, evolution, and outcome of ASSD. In this study, we retrospectively recorded the time of onset, characteristics, clustering of triad findings, and survival of 828 ASSD patients (593 anti-Jo1, 95 anti-PL7, 84 anti-PL12, 38 anti-EJ, and 18 anti-OJ), referring to AENEAS (American and European NEtwork of Antisynthetase Syndrome) collaborative group's cohort. Comparisons were performed first between all ARS cases and then, in the case of significance, while using anti-Jo1 positive patients as the reference group. The characteristics of triad findings were similar and the onset mainly began with a single triad finding in all groups despite some differences in overall prevalence. The "ex-novo" occurrence of triad findings was only reduced in the anti-PL12-positive cohort, however, it occurred in a clinically relevant percentage of patients (30%). Moreover, survival was not influenced by the underlying anti-aminoacyl tRNA synthetase antibodies' positivity, which confirmed that antisynthetase syndrome is a heterogeneous condition and that antibody specificity only partially influences the clinical presentation and evolution of this condition

Pediatric trauma and emergency surgery: an international cross-sectional survey among WSES members

Background: In contrast to adults, the situation for pediatric trauma care from an international point of view and the global management of severely injured children remain rather unclear. The current study investigates structural management of pediatric trauma in centers of different trauma levels as well as experiences with pediatric trauma management around the world. Methods: A web-survey had been distributed to the global mailing list of the World Society of Emergency Surgery from 10/2021-03/2022, investigating characteristics of respondents and affiliated hospitals, case-load of pediatric trauma patients, capacities and infrastructure for critical care in children, trauma team composition, clinical work-up and individual experiences with pediatric trauma management in response to patients´ age. The collaboration group was subdivided regarding sizes of affiliated hospitals to allow comparisons concerning hospital volumes. Comparable results were conducted to statistical analysis. Results: A total of 133 participants from 34 countries, i.e. 5 continents responded to the survey. They were most commonly affiliated with larger hospitals (> 500 beds in 72.9%) and with level I or II trauma centers (82.0%), respectively. 74.4% of hospitals offer unrestricted pediatric medical care, but only 63.2% and 42.9% of the participants had sufficient experiences with trauma care in children ≤ 10 and ≤ 5 years of age (p = 0.0014). This situation is aggravated in participants from smaller hospitals (p < 0.01). With regard to hospital size (≤ 500 versus > 500 in-hospital beds), larger hospitals were more likely affiliated with advanced trauma centers, more elaborated pediatric intensive care infrastructure (p < 0.0001), treated children at all ages more frequently (p = 0.0938) and have higher case-loads of severely injured children < 12 years of age (p = 0.0009). Therefore, the majority of larger hospitals reserve either pediatric surgery departments or board-certified pediatric surgeons (p < 0.0001) and in-hospital trauma management is conducted more multi-disciplinarily. However, the majority of respondents does not feel prepared for treatment of severe pediatric trauma and call for special educational and practical training courses (overall: 80.2% and 64.3%, respectively). Conclusions: Multi-professional management of pediatric trauma and individual experiences with severely injured children depend on volumes, level of trauma centers and infrastructure of the hospital. However, respondents from hospitals at all levels of trauma care complain about an alarming lack of knowledge on pediatric trauma management