A modified approach to percutaneous ultrasound-guided left stellate ganglion block for drug-refractory electrical storm: a case report.

Background: The use of percutaneous stellate ganglion block (SGB) in the management of drug-refractory electrical storm (ES) has been increasingly reported in the last years. Few data are available on the safety, duration, and dosage of local anaesthetic used. Case summary: A 66-year-old male patient with a history of ischaemic cardiomyopathy and an implantable cardioverter-defibrillator (ICD) presented to the emergency room complaining several ventricular arrhythmias and ICD shocks received in the last 24 h. He was treated with many lines of anti-arrhythmic drugs but his condition deteriorated with cardiovascular instability and respiratory distress, so he was intubated. The ES still worsened (82 episodes of ventricular arrhythmias), so we performed an ultrasound-guided left SGB, using a modified technique, with success in suppressing the ventricular arrhythmias. The patient was then treated with electrophysiological study and catheter ablation. Discussion: The ultrasound approach to SGB is feasible in emergency setting, and it is safe and effective also using a modified and easier technique in patient with difficult sonographic visualization of the neck structures. Moreover, it is possible and safe to use a combination of short-acting rapid-onset local anaesthetic with a long-lasting one with a good outcome.

Real-time monitoring of the dynamics and interactions of bacteria and the early-stage formation of biofilms.

Bacterial biofilms are complex colonies of bacteria adhered to a static surface and/or one to another. Bacterial biofilms exhibit high resistance to antimicrobial agents and can cause life-threatening nosocomial infections. Despite the effort of the scientific community investigating the formation and growth of bacterial biofilms, the preliminary interaction of bacteria with a surface and the subsequent early-stage formation of biofilms is still unclear. In this study, we present real-time, label-free monitoring of the interaction of Escherichia coli and Pseudomonas aeruginosa bacteria with untreated glass control surfaces and surfaces treated with benzalkonium chloride, a chemical compound known for its antimicrobial properties. The proof of principle investigation has been performed in a standard inverted optical microscope exploiting the optical phenomenon of caustics as a tool for monitoring bacterial diffusion and early adhesion and associated viability. The enhanced resolving power of the optical set-up allowed the monitoring and characterization of the dynamics of the bacteria, which provided evidence for the relationship between bacterial adhesion dynamics and viability, as well as the ability to form a biofilm. Viable bacteria adhered to the surface exhibited noticeable sliding or rotary dynamics while bacteria killed by surface contact remained static once adhered to the surface. This difference in dynamics allowed the early detection of biofilm formation and offers the potential to quantify the efficiency of antimicrobial surfaces and coatings.

Settling dynamics of nanoparticles in simple and biological media.

The biological response of organisms exposed to nanoparticles is often studied in vitro using adherent monolayers of cultured cells. In order to derive accurate concentration-response relationships, it is important to determine the local concentration of nanoparticles to which the cells are actually exposed rather than the nominal concentration of nanoparticles in the cell culture medium. In this study, the sedimentation-diffusion process of different sized and charged gold nanoparticles has been investigated in vitro by evaluating their settling dynamics and by developing a theoretical model to predict the concentration depth profile of nanoparticles in solution over time. Experiments were carried out in water and in cell culture media at a range of controlled temperatures. The optical phenomenon of caustics was exploited to track nanoparticles in real time in a conventional optical microscope without any requirement for fluorescent labelling that potentially affects the dynamics of the nanoparticles. The results obtained demonstrate that size, temperature and the stability of the nanoparticles play a pivotal role in regulating the settling dynamics of nanoparticles. For gold nanoparticles larger than 60 nm in diameter, the initial nominal concentration did not accurately represent the concentration of nanoparticles local to the cells. Finally, the theoretical model proposed accurately described the settling dynamics of the nanoparticles and thus represents a promising tool to support the design of in vitro experiments and the study of concentration-response relationships.

Health-related quality of life (HRQoL) after stroke: Positive relationship between lower extremity and balance recovery.

Background: Stroke survivors have poor long-term quality of life (QoL), especially in the dimensions of mobility and daily activities. Objectives: We aimed to investigate how clinical variables influence QoL during subacute stroke rehabilitation. Methods: We assessed the evolution of the health-related QoL (HRQoL), the balance skills, the sensory-motor functions, and the ability in the activity of daily living in 25 hospitalized patients (60.6 ± 11.14 years old; 32% female) during a period of 2 months of stroke rehabilitation. We used the Stroke-Specific Quality of Life scale (SSQoL) to assess the HRQoL; the Berg Balance Scale to assess gait and balance functions; the Fugl-Meyer Assessment scale for sensory-motor functions of upper (UE) and lower limb (LE); and the Barthel Index for activity of daily living. All data have been investigated with the repeated-measures analysis of variance before and after normalization. Multiple Regression Analysis (MRA) has been performed on the normalized data and between the normalized data and the demographic characteristics (Gender; Age; Lesion side). Results: A significant improvement was found in all the assessed scales during the time of observation. MRA shows a positive regression between HRQoL and the motor recovery of LE and between HRQoL and the balance skills in 60 days from the stroke (MR = 0.88; respectively: p = 0.004 and p = 0.02). Conclusions: Our result shows that LE motor recovery impacts the QoL more than motor recovery of UE after 60 days of neurorehabilitation. This finding is strengthened by a positive regression between balance skills and QoL.

The influence of inter-particle forces on diffusion at the nanoscale.

Van der Waals and electrostatic interactions are the dominant forces acting at the nanoscale and they have been reported to directly influence a range of phenomena including surface adhesion, friction, and colloid stability but their contribution on nanoparticle diffusion dynamics is still not clear. In this study we evaluated experimentally the changes in the diffusion coefficient of nanoparticles as a result of varying the magnitude of Van der Waals and electrostatic forces. We controlled the magnitude of these forces by varying the ionic strength of a salt solution, which has been shown to be a parameter that directly controls the forces, and found by tracking single nanoparticles dispersed in solutions with different salt molarity that the diffusion of nanoparticles increases with the magnitude of the electrostatic forces and Van der Waals forces. Our results demonstrate that these two concurrently dynamic forces play a pivotal role in driving the diffusion process and must be taken into account when considering nanoparticle behaviour.

Enteroglial-derived S100B protein integrates bacteria-induced Toll-like receptor signalling in human enteric glial cells.

OBJECTIVE: Enteric glial cells (EGC) have been suggested to participate in host-bacteria cross-talk, playing a protective role within the gut. The way EGC interact with microorganisms is still poorly understood. We aimed to evaluate whether: EGC participate in host-bacteria interaction; S100B and Toll-like receptor (TLR) signalling converge in a common pathway leading to nitric oxide (NO) production. DESIGN: Primary cultures of human EGC were exposed to pathogenic (enteroinvasive Escherichia coli; EIEC) and probiotic (Lactobacillus paracasei F19) bacteria. Cell activation was assessed by evaluating the expression of cFos and major histocompatibility complex (MHC) class II molecules. TLR expression in EGC was evaluated at both baseline and after exposure to bacteria by real-time PCR, fluorescence microscopy and western blot analysis. S100B expression and NO release from EGC, following exposure to bacteria, were measured in the presence or absence of specific TLR and S100B pathway inhibitors. RESULTS: EIEC activated EGC by inducing the expression of cFos and MHC II. EGC expressed TLR at baseline. Pathogens and probiotics differentially modulated TLR expression in EGC. Pathogens, but not probiotics, significantly induced S100B protein overexpression and NO release from EGC. Pretreatment with specific inhibitors of TLR and S100B pathways abolished bacterial-induced NO release from EGC. CONCLUSIONS: Human EGC interact with bacteria and discriminate between pathogens and probiotics via a different TLR expression and NO production. In EGC, NO release is impaired in the presence of specific inhibitors of the TLR and S100B pathways, suggesting the presence of a novel common pathway involving both TLR stimulation and S100B protein upregulation.

Effects of long-term PPI treatment on producing bowel symptoms and SIBO.

BACKGROUND: Gastroesophageal reflux disease (GERD), including erosive reflux disease and non-erosive reflux disease (NERD), is a chronic disease with a significant negative effect on quality of life. State-of-the-art treatment involves proton pump inhibitors (PPIs). However, relapse of symptoms occurs in the majority of the patients who require recurrent or continuous therapy. Although PPIs are well tolerated, little information is available about gastrointestinal side effects. AIM: To evaluate the effects of long-term PPI treatment on development of bowel symptoms and/or small intestinal bacterial overgrowth (SIBO). METHODS: Patients with NERD not complaining of bowel symptoms were selected by upper endoscopy, 24-h pH-metry and a structured questionnaire concerning severity and frequency of bloating, flatulence, abdominal pain, diarrhoea and constipation. Patients were treated with esomeprazole 20 mg bid for 6 months. Prior to and after 8 weeks and 6 months of therapy, patients received the structured questionnaire and underwent evaluation of SIBO by glucose hydrogen breath test (GHBT). RESULTS: Forty-two patients with NERD were selected out of 554 eligible patients. After 8 weeks of PPI treatment, patients complained of bloating, flatulence, abdominal pain and diarrhoea in 43%, 17%, 7% and 2%, respectively. After 6 months, the incidence of bowel symptoms further increased and GHBT was found positive in 11/42 (26%) patients. By a post hoc analysis, a significant (P < 0·05) percentage of patients (8/42) met Rome III criteria for irritable bowel syndrome. CONCLUSIONS: Prolonged PPI treatment may produce bowel symptoms and SIBO; therefore, the strategy of step-down or on-demand PPI therapy should be encouraged in GERD.

Correlation between oesophageal acid exposure and dyspeptic symptoms in patients with nonerosive reflux disease.

BACKGROUND & AIMS: Oesophageal acidification induces dyspeptic symptoms in healthy individuals. This study aimed to evaluate the correlation between oesophageal acid exposure and dyspeptic symptoms in patients with nonerosive reflux disease. METHODS: A total of 68 patients with dominant symptoms of heartburn, negative upper gastrointestinal endoscopy and concomitant dyspeptic symptoms participated in the study. The severity of dyspepsia and reflux-related symptoms was evaluated, and 24-h gastro-oesophageal pH-monitoring study was performed in all patients at baseline and after 4 weeks of therapy with esomeprazole 40 mg. RESULTS: Oesophageal basal acid exposure was pathological in 43 patients and normal in 25 patients, with a similar prevalence and severity of individual dyspeptic symptoms in the two groups. A significant correlation between reflux and dyspepsia scores was observed in the subgroup of patients with normal, but not in those with abnormal pHmetry (r=0.4, P=0.04 and r=0.2 P=0.07, respectively). After esomeprazole, a reduction in severity of dyspepsia (>or=50% with respect to baseline) was observed, independent of improvement of reflux-associated symptoms. Improvement in dyspepsia was, however, similar in patients with normal and abnormal basal acid exposure (14/25 vs. 33/43, respectively, P=NS). CONCLUSION: Dyspeptic symptoms coexist in a subset of nonerosive reflux disease patients, but prevalence and severity of the symptoms seems to be independent of oesophageal acid exposure.

Symptoms and pathophysiological correlations in patients with constipation and functional dyspepsia.

INTRODUCTION: Patients with constipation often report dyspeptic symptoms, but whether constipation is associated with specific dyspeptic symptoms and altered gastrointestinal (GI) motility, remains to be established. Our aim was to study symptoms association and GI motility parameters in patients with constipation and functional dyspepsia. PATIENTS AND METHOD: 42 patients with different symptoms and severity of constipation and dyspepsia were enrolled. Scintigraphic gastric emptying, colonic transit time and gallbladder contraction were studied in all subjects. RESULTS: No significant association was observed between individual symptoms of constipation and dyspepsia. Patients with more severe constipation did not have higher dyspepsia severity scores. Colonic transit time, gastric half emptying and gallbladder contraction were not significantly correlated. Although patients with severe nausea had faster colonic transit than those with absent/mild symptom (19 +/- 2 vs. 48 +/- 7 h; p < 0.05), the multivariate analysis only revealed a significant association between severe postprandial fullness, delayed t1/2 (OR 1.05, CI 1-1.1) and impaired gallbladder contraction (OR 0.94, CI 0.89-0.99). CONCLUSIONS: Constipation was not associated with severity, or any particular dyspeptic symptom. Although motor abnormalities of both colon and proximal GI tract regions existed in the subset of constipated dyspeptic patients, they did not seem associated with the genesis of different dyspeptic symptoms.