Parallel and perpendicular cascades in solar wind turbulence

MHD-scale fluctuations in the velocity, magnetic, and density fields of the solar wind are routinely observed. The evolution of these fluctuations, as they are transported radially outwards by the solar wind, is believed to involve both wave and turbulence processes. The presence of an average magnetic field has important implications for the anisotropy of the fluctuations and the nature of the turbulent wavenumber cascades in the directions parallel and perpendicular to this field. In particular, if the ratio of the rms magnetic fluctuation strength to the mean field is small, then the parallel wavenumber cascade is expected to be weak and there are difficulties in obtaining a cascade in frequency. The latter has been invoked in order to explain the heating of solar wind fluctuations (above adiabatic levels) via energy transfer to scales where ion-cyclotron damping can occur. Following a brief review of classical hydrodynamic and magnetohydrodynamic (MHD) cascade theories, we discuss the distinct nature of parallel and perpendicular cascades and their roles in the evolution of solar wind fluctuations

Disseminated and Relapsing Cryptococcosis: What We Still Have to Learn—a Case Series and Review of Literature

AbstractTwo cases of disseminated cryptococcosis are described. The first was an HIV-infected patient where cryptococcosis was diagnosed as "unmasking immune reconstitution syndrome"; the second was an immunosuppressed patient with multiple myeloma. In both cases, a definitive healing could not be reached despite long therapeutic approaches. This review summarizes both the most recent and relevant studies about disseminated and refractory form of cryptococcal infections and identifies research gaps. Given the limited data, we draw some conclusions with respect to management from literature: not clear and accepted indication are available regarding disseminated cryptococcosis, no specific schemes were identified, and the duration of therapy is usually decided case by case and supported only by case reports. In this perspective, usually standard therapeutic schemes and duration of induction depend on multiple factors (e.g., neurologic deficit, non-HIV/non transplant status, CSF culture positivity at 2 weeks, etc.). We found that there are no empiric and literature data that support a role of cryptococcal serum antigen (CRAG) in guiding the antifungal therapy; with the data collected, we think that although is possible, it is very rare to find disseminated cryptococcosis with negative CRAG. We looked also for the more important risk factor of recurrence. Some possible causes explored are risk of azole resistant strains, pre-existent conditions of patients that play a permissive role and the common situation where flucytosine is unavailable that led to suboptimal induction phase of therapy. Herein, we discuss disseminated cryptococcosis with a particular attention to antifungal therapy, role of cryptococcal antigen, and risk factors for recurrence of disease

Proposal for a New Score-Based Approach To Improve Efficiency of Diagnostic Laboratory Workflow for Acute Bacterial Meningitis in Adults

Microbiological tests on cerebrospinal fluid (CSF) utilize a common urgent-care procedure that does not take into account the chemical and cytological characteristics of the CSF, resulting sometimes in an unnecessary use of human and diagnostic resources. The aim of this study was to retrospectively validate a simple scoring system (bacterial meningitis-Careggi score [BM-CASCO]) based on blood and CSF sample chemical/cytological parameters for evaluating the probability of acute bacterial meningitis (ABM) in adults. BM-CASCO (range, 0 to 6) was defined by the following parameters: CSF cell count, CSF protein levels, CSF lactate levels, CSF glucose-to-serum glucose ratio, and peripheral neutrophil count. BM-CASCO was retrospectively calculated for 784 cases of suspected ABM in adult subjects observed during a four-and-a-half-year-period (2010 to 2014) at the emergency department (ED) of a large tertiary-care teaching hospital in Italy. Among the 28 confirmed ABM cases (3.5%), Streptococcus pneumoniae was the most frequent cause (16 cases). All ABM cases showed a BM-CASCO value of ≥3. Most negative cases (591/756) exhibited a BM-CASCO value of ≤1, which was adopted in our laboratory as a cutoff to not proceed with urgent microbiological analysis of CSF in cases of suspected ABM in adults. During a subsequent 1-year follow-up, the introduction of the BM-CASCO in the diagnostic workflow of ABM in adults resulted in a significant decrease in unnecessary microbiological analysis, with no false negatives. In conclusion, BM-CASCO appears to be an accurate and simple scoring system for optimization of the microbiological diagnostic workflow of ABM in adults

Cohort profile: The Observational cohort for the study of DOlutegravir in Antiretroviral Combination REgimens (ODOACRE)

The Observational cohort for the study of DOlutegravir in Antiretroviral Combination REgimens (ODOACRE) cohort was established in Italy in 2016 to evaluate the overall efficacy and tolerability of dolutegravir (DTG)-based antiretroviral (ARV) regimens in clinical practice

Beware erysipelas: renal disease is just around the corner

We describe a case of erysipelas caused by Streptococcus Group G to draw attention to organ and systemic complications that may be associated with this disease. Group G streptococcal infection affected a 70-year old woman following a small skin wound at the base of her second left toe. On admittance to the emergency department, the patient’s urine was dark from macrohematuria. She later developed septic shock. Cutaneous and renal symptoms were kept in check with antibiotic therapy, and she fully recovered from the septic shock after receiving specific therapies. This case shows that erysipelas is not just a disease of the skin and soft tissues, but one that may be associated with organ diseases and systemic complications. The patient completely recovered from both the cutaneous and kidney pathologies after antibiotic therapy

Treatment with anti-SARS-CoV-2 monoclonal antibodies in pregnant and postpartum women: first experiences in Florence, Italy

PURPOSE: Pregnant and postpartum women are at increased risk of developing severe COVID-19. Monoclonal antibodies (mAbs) are now widely used in high-income countries to treat mild to moderate COVID-19 outpatients at risk for developing severe disease. Very few data are available on the use of mAbs in special populations, including pregnant and postpartum women. Here we present our early experience with mAbs in these two populations. METHODS: Electronic records of pregnant and postpartum women treated with mAbs at Careggi University Hospital, Florence, were retrieved. Relevant data were extracted (age, presence of risk factors for COVID-19, oxygen support, mAb type, gestational age, and pregnancy status). When available, outcomes at 28 days after administration were also included. RESULTS: From March 1st to September 30th 2021, eight pregnant and two postpartum women have been treated with mAbs at our center. The median age was 31 years (IQR 30–33.5, range 29–38), median gestational age was 24 weeks. Seven patients had additional risk factors. According to the Italian disposition, all patients received casirivimab/imdevimab, with five receiving a 2.4 mg dose and five receiving a 8 g dose. Eight patients improved. One developed myocarditis, considered a COVID-19 complication. Another required a transient increase of low flow oxygen support before improving and being discharged. At a 28 days follow-up, all patients were clinically recovered. We did not observe mAbs related adverse events. CONCLUSION: Although preliminary data should be interpreted with caution, it is remarkable how mAbs were well tolerated by pregnant women with COVID-19. Further data on mAbs in this special population should be collected but the use of mAbs in pregnant and postpartum patients should be considered. Even thus oral antivirals are becoming available, they are not recommended in pregnant and postpartum women. This population may specifically benefit from treatment with last generation mAbs