Neurofeedback Tunes Scale-Free Dynamics in Spontaneous Brain Activity

Brain oscillations exhibit long-range temporal correlations (LRTCs), which reflect the regularity of their fluctuations: low values representing more random (decorrelated) while high values more persistent (correlated) dynamics. LRTCs constitute supporting evidence that the brain operates near criticality, a state where neuronal activities are balanced between order and randomness. Here, healthy adults used closed-loop brain training (neurofeedback, NFB) to reduce the amplitude of alpha oscillations, producing a significant increase in spontaneous LRTCs post-training. This effect was reproduced in patients with post-traumatic stress disorder, where abnormally random dynamics were reversed by NFB, correlating with significant improvements in hyperarousal. Notably, regions manifesting abnormally low LRTCs (i.e., excessive randomness) normalized toward healthy population levels, consistent with theoretical predictions about self-organized criticality. Hence, when exposed to appropriate training, spontaneous cortical activity reveals a residual capacity for "self-tuning" its own temporal complexity, despite manifesting the abnormal dynamics seen in individuals with psychiatric disorder. Lastly, we observed an inverse-U relationship between strength of LRTC and oscillation amplitude, suggesting a breakdown of long-range dependence at high/low synchronization extremes, in line with recent computational models. Together, our findings offer a broader mechanistic framework for motivating research and clinical applications of NFB, encompassing disorders with perturbed LRTCs.

Fluorescent Labeling and 2-Photon Imaging of Mouse Tooth Pulp Nociceptors

Retrograde fluorescent labeling of dental primary afferent neurons (DPANs) has been described in rats through crystalline fluorescent DiI, while in the mouse, this technique was achieved with only Fluoro-Gold, a neurotoxic fluorescent dye with membrane penetration characteristics superior to the carbocyanine dyes. We reevaluated this technique in the rat with the aim to transfer it to the mouse because comprehensive physiologic studies require access to the mouse as a model organism. Using conventional immunohistochemistry, we assessed in rats and mice the speed of axonal dye transport from the application site to the trigeminal ganglion, the numbers of stained DPANs, and the fluorescence intensity via 1) conventional crystalline DiI and 2) a novel DiI formulation with improved penetration properties and staining efficiency. A 3-dimensional reconstruction of an entire trigeminal ganglion with 2-photon laser scanning fluorescence microscopy permitted visualization of DPANs in all 3 divisions of the trigeminal nerve. We quantified DPANs in mice expressing the farnesylated enhanced green fluorescent protein (EGFPf) from the transient receptor potential cation channel subfamily M member 8 (TRPM8^EGFPf/+) locus in the 3 branches. We also evaluated the viability of the labeled DPANs in dissociated trigeminal ganglion cultures using calcium microfluorometry, and we assessed the sensitivity to capsaicin, an agonist of the TRPV1 receptor. Reproducible DiI labeling of DPANs in the mouse is an important tool 1) to investigate the molecular and functional specialization of DPANs within the trigeminal nociceptive system and 2) to recognize exclusive molecular characteristics that differentiate nociception in the trigeminal system from that in the somatic system. A versatile tool to enhance our understanding of the molecular composition and characteristics of DPANs will be essential for the development of mechanism-based therapeutic approaches for dentine hypersensitivity and inflammatory tooth pain.

Gender-specific impairment of in vitro sinoatrial node chronotropic responses and of myocardial ischemia tolerance in rats exposed prenatally to betamethasone

Excessive fetal glucocorticoid exposure has been linked to increased susceptibility to hypertension and cardiac diseases in the adult life, a process called fetal programming. The cardiac contribution to the hypertensive phenotype of glucocorticoid-programmed progeny is less known, therefore, we investigated in vitro cardiac functional parameters from rats exposed in utero to betamethasone. Pregnant Wistar rats received vehicle (VEH) or betamethasone (BET, 0.1mg/kg, i.m.) at gestational days 12, 13, 18 and 19. Male and female offspring were killed at post-natal day 30 and the right atrium (RA) was isolated to in vitro evaluation of drug-induced chronotropic responses. Additionally, whole hearts were retrograde-perfused in a Langendorff apparatus and infarct size in response to in vitro ischemia/reperfusion (I/R) protocol was evaluated. Male and female progeny from BET-exposed pregnant rats had reduced birth weight, a hallmark of fetal programming. Male BET-progeny had increased basal RA rate, impaired chronotropic responses to noradrenaline and adenosine, and increased myocardial damage to I/R. Though a 12-fold reduction in the negative chronotropic responses to adenosine, the effects of non-metabolisable adenosine receptor agonists 5'-(N-ethylcarboxamido)adenosine or 2-Chloro-adenosine were not different between VEH- and BET-exposed male rats. BET-exposed female offspring presented no cardiac dysfunction. Prenatal BET exposure engenders male-specific impairment of sinoatrial node function and on myocardial ischemia tolerance resulting, at least in part, from an increased adenosine metabolism in the heart. In light of the importance of adenosine in the cardiac physiology our results suggest a link between reduced adenosinergic signaling and the cardiac dysfunctions observed in glucocorticoid-induced fetal programming.

Inpatient treatment of patients with acute idiopathic peripheral facial palsy: A population-based healthcare research study

OBJECTIVES

To determine the inpatient management for patients with acute idiopathic facial palsy (IFP) in Thuringia, Germany.

DESIGN

Population-based study.

SETTING

All inpatients with IFP in all hospitals with departments of otolaryngology and neurology in 2012, in the German federal state, Thuringia.

MAIN OUTCOME MEASURES

Patients' characteristics and treatment were compared between departments, and the probability of recovery was tested.

RESULTS

A total of 291 patients were mainly treated in departments of otolaryngology (55%) and neurology (36%). Corticosteroid treatment was the predominant therapy (84.5%). The probability to receive a facial nerve grading (odds ratio [OR=12.939; 95% confidence interval [CI]=3.599 to 46.516), gustatory testing (OR=6.878; CI=1.064 to 44.474) and audiometry (OR=32.505; CI=1.485 to 711.257) was significantly higher in otolaryngology departments, but lower for cranial CT (OR=0.192; CI=0.061 to 0.602), cerebrospinal fluid examination (OR=0.024; CI=0.006 to 0.102). A total of 131 patients (45%) showed a recovery to House-Brackmann grade≤II. A pathological stapedial reflex test (Hazard ratio [HR]=0.416; CI=0.180 to 0.959) was the only independent diagnostic predictor of worse outcome. Prednisolone dose >500 mg (HR=0.579; CI 0.400 to 0.838) and no adjuvant physiotherapy (HR=0.568; CI=0.407 to 0.794) were treatment-related predictors of worse outcome.

CONCLUSIONS

Inpatient treatment of IFP seems to be highly variable in daily practice, partly depending on the treating discipline and despite the availability of evidence-based guidelines. The population-based recovery rate was worse than reported in clinical trials.

Preclinical and clinical evaluation of carbohydrate immunopharmaceuticals in the prevention of sepsis and septic sequelae

Sepsis and sepsis syndrome are significant causes of morbidity and mortality in critically ill patients. Despite technological and therapeutic advances in critical care, sepsis continues to be a pivotal factor in 20-50 % of deaths in surgical intensive care units. It is clear that alternative approaches to the prevention and/or treatment of sepsis must be found. Preclinical data indicate that macrophage activation with (1→3)-β-D-glucans will ameliorate sequelae associated with Gram-negative septicemia. Recent clinical data indicate that macrophage activation with (1→3)-β-D-glucans will significantly reduce septic morbidity and mortality in trauma and/or high-risk surgical patients. This work reviews the preclinical and clinical evaluation of (1→3)-β-D-glucans in the prevention of sepsis and septic sequelae.

Biomonitoring of prenatal analgesic intake and correlation with infantile anti-aeroallergens IgE

An association between prenatal acetaminophen or ibuprofen intake and an increased risk of asthma and increased IgE level in children is discussed in various epidemiological studies. Although the molecular mechanistic link is still unknown, the question whether or not acetaminophen and/or ibuprofen are safe pain medications during pregnancy arose. In this study, we associate maternal acetaminophen and ibuprofen intake during pregnancy and breastfeeding to infantile asthma phenotypes and elevated IgE level. Therefore, we analysed questionnaires from a local mother-child cohort and monitored drug intake by LC-MS biomonitoring in urine. No association was found between drug intake and any analysed health outcome using questionnaire data. For the information obtained from biomonitoring, no association was found for ibuprofen and acetaminophen intakes during breastfeeding. However, an association between prenatal acetaminophen intake and increased infantile IgEs related to aeroallergens was statistically detected, but not for asthma phenotypes.

Feasibility and safety of conservative surgery for the treatment of spermatic cord leiomyosarcoma

OBJECTIVES

To assess the feasibility and the safety of conservative surgery to treat spermatic cord leiomyosarcoma.

METHODS

Patients undergoing inguinoscrotal exploration in 10 different Urological Centers with diagnosis of leiomyosarcoma were enrolled. Preoperative evaluation included physical examination, Scrotal US, Abdominal CT and Scrotal MRI in selected cases. Patients underwent organ sparing surgery or orchiectomy in case of intraoperative FSE was positive for a local infiltration. Data collected were: age, presence of infiltration, length of the lesion, number of lesions, definitive histological outcome, pre and postoperative testosterone level. Follow up was performed with abdomen CT scan and scrotal US.

RESULTS

From January 2007 to December 2013, 23 patients (mean age: 64.7 yrs) were diagnosed with spermatic cord leiomyosarcoma. Each patients underwent scrotal US. 10 patients underwent radical orchiectomy and 13 patients underwent conservative surgery. Mean follow up was 36.5 months. 5 patients (21.7%) developed a recurrent disease, 18 patients (78.3%) had a negative follow up (mean time: 40.8 months). Statistical analysis reveals that there is a significant correlation between number of lesions, length of the lesions and recurrent disease.

CONCLUSIONS

Spermatic cord leiomyosarcoma is a rare disease. Conservative surgical treatment of spermatic cord leiomyosarcoma is a feasible therapeutic option for small, single and not infiltrating lesion.

Prevalence of hepatitis B virus infection among health care workers in a tertiary hospital in Tanzania

Background

Sub-Saharan Africa has a high prevalence of hepatitis B virus (HBV) infections. Health care workers (HCWs) are at high risk of contracting HBV infection through their occupation. Vaccination of HCWs against HBV is standard practice in many countries, but is often not implemented in resource-poor settings. We aimed with this cross-sectional study to determine HBV prevalence, HCW vaccination status, and the risk factors for HCWs contracting HBV infection in Tanzania.

Methods

We enrolled 600 HCWs from a tertiary Tanzanian hospital. Their demographics, medical histories, HBV vaccination details and risk factors for contracting blood-borne infections were collected using a standardized questionnaire. Serum samples were tested for HBV and hepatitis C virus (HCV) markers by ELISA techniques, PCR and an anti-HBs rapid test. HCWs were divided in two subgroups: those at risk of contracting HBV (rHCW 79.2 %) via exposure to potentially infectious materials, and those considered not at risk of contracting HBV (nrHCW, 20.8 %).

Results

The overall prevalence of chronic HBV infection (HBsAg+, anti-HBc+, anti-HBs-) was 7.0 % (42/598). Chronic HBV infection was found in 7.4 % of rHCW versus 5.6 % of nrHCW (p-value = 0.484). HCWs susceptible to HBV (HBsAg-, anti-HBc-, anti-HBs-) comprised 31.3 %. HBV immunity achieved either by healed HBV infection (HBsAg-, anti-HBc+, anti-HBs+) or by vaccination (HBsAg-, anti-HBc-, anti-HBs+) comprised 36.5 % and 20.2 %, respectively. 4.8 % of participants had indeterminate results (HBsAg-, anti-HBc+, anti-HBc-IgM-, anti-HBs-). Only 77.1 % of HCWs who received a full vaccination course had an anti-HBs titer >10 ml/U. An anti-HBs point-of-care test was 80.7 % sensitive and 96.9 % specific. There was a significantly higher risk for contracting HBV (anti-HBc+) among those HCW at occupational risk (rHCW) of older age (odds ratios (OR) in rHCW 3.297, p < 0.0001 vs. nrHCW 1.385, p = 0.606) and among those HCW being employed more than 11 years (OR 2.51, p < 0.0001***). HCV prevalence was low (HCV antibodies 1.2 % and HCV-RNA 0.3 %).

Conclusions

Chronic HBV infection is common among Tanzanian HCWs. One third of HCWs were susceptible to HBV infection, highlighting the need for vaccination. Due to high prevalence of naturally acquired immunity against HBV pre-testing might be a useful tool to identify susceptible individuals.

Predominance of dfrG as determinant of trimethoprim resistance in imported Staphylococcus aureus

To investigate the global occurrence of trimethoprim-sulfamethoxazole resistance and the genetic mechanisms of trimethoprim resistance, we analysed Staphylococcus aureus from travel-associated skin and soft-tissue infections treated at 13 travel clinics in Europe. Thirty-eight per cent (75/196) were trimethoprim-resistant and 21% (41/196) were resistant to trimethoprim-sulfamethoxazole. Among methicillin-resistant S. aureus, these proportions were 30% (7/23) and 17% (4/23), respectively. DfrG explained 92% (69/75) of all trimethoprim resistance in S. aureus. Travel to South Asia was associated with the highest risk of acquiring trimethoprim-sulfamethoxazole-resistant S. aureus. We conclude that globally dfrG is the predominant determinant of trimethoprim resistance in human S. aureus infection.

Scikit-learn

Machine learning is a pervasive development at the intersection of statistics and computer science. While it can benefit many data-related applications, the technical nature of the research literature and the corresponding algorithms slows down its adoption. Scikit-learn is an open-source software project that aims at making machine learning accessible to all, whether it be in academia or in industry. It benefits from the general-purpose Python language, which is both broadly adopted in the scientific world, and supported by a thriving ecosystem of contributors. Here we give a quick introduction to scikit-learn as well as to machine-learning basics.