Nematic liquid crystal reorientation around multi-walled carbon nanotubes mapped via Raman microscopy.

We have studied the formation of topological defects in liquid crystal (LC) matrices induced by multiwalled carbon nanotubes (MWCNTs) and external electric fields. The defects are ascribable to a distortion of the LC molecular director in proximity of the MWCNT surface. The system is analyzed macroscopically using spectroscopic variable angle ellipsometry. Concurrently, confocal micro-Raman spectroscopy is used to study the system state at the microscale. This allows to acquire a three-dimensional, spatially-resolved map of the topological defect, determining scale length variations and orientation topography of the LC molecules around the MWCNT.

Toward hyperuniform disordered plasmonic nanostructures for reproducible surface-enhanced Raman spectroscopy.

We report on the self-assembling of clusters of gold-nanoparticles (Au-NPs) directed by the phase separation of poly(styrene)-b-poly(methylmethacrylate) (PS-b-PMMA) block-copolymer (BCP) on indium tin oxide coated glass, which induces the onset of vertical lamellar domains. After thermal evaporation of gold on BCP, Au-NPs of 4 nm are selectively included into PS-nanodomains by thermal annealing, and then clustered with large density of hot spots (> 10(4) µm(2)) in a random two-dimensional pattern. The resulting nanostructure exhibits near-hyperuniform long-range correlations. The consequent large degree of homogeneity of this isotropic plasmonic pattern gives rise to a highly reproducible Surface-Enhanced Raman Scattering (SERS) enhancement factor over the centimeter scale (std. dev. ∼ 10% over 0.25 cm(2)). We also discuss the application of a static electric field for modulating the BCP host morphology. The electric field induces an alignment of Au-NP clusters into ordered linear chains, exhibiting a stronger SERS activity, but reduced SERS spatial reproducibility.

Street crossing behavior in younger and older pedestrians: an eye- and head-tracking study.

BACKGROUND: Crossing a street can be a very difficult task for older pedestrians. With increased age and potential cognitive decline, older people take the decision to cross a street primarily based on vehicles' distance, and not on their speed. Furthermore, older pedestrians tend to overestimate their own walking speed, and could not adapt it according to the traffic conditions. Pedestrians' behavior is often tested using virtual reality. Virtual reality presents the advantage of being safe, cost-effective, and allows using standardized test conditions. METHODS: This paper describes an observational study with older and younger adults. Street crossing behavior was investigated in 18 healthy, younger and 18 older subjects by using a virtual reality setting. The aim of the study was to measure behavioral data (such as eye and head movements) and to assess how the two age groups differ in terms of number of safe street crossings, virtual crashes, and missed street crossing opportunities. Street crossing behavior, eye and head movements, in older and younger subjects, were compared with non-parametric tests. RESULTS: The results showed that younger pedestrians behaved in a more secure manner while crossing a street, as compared to older people. The eye and head movements analysis revealed that older people looked more at the ground and less at the other side of the street to cross. CONCLUSIONS: The less secure behavior in street crossing found in older pedestrians could be explained by their reduced cognitive and visual abilities, which, in turn, resulted in difficulties in the decision-making process, especially under time pressure. Decisions to cross a street are based on the distance of the oncoming cars, rather than their speed, for both groups. Older pedestrians look more at their feet, probably because of their need of more time to plan precise stepping movement and, in turn, pay less attention to the traffic. This might help to set up guidelines for improving senior pedestrians' safety, in terms of speed limits, road design, and mixed physical-cognitive trainings.

Cortico-muscular coherence as an index of fatigue in multiple sclerosis.

BACKGROUND: Highly common in multiple sclerosis (MS), fatigue severely impacts patients' daily lives. Previous findings of altered connectivity patterns led to the hypothesis that the distortion of functional connections within the brain-muscle circuit plays a crucial pathogenic role. OBJECTIVE: The objective of this paper is to identify markers sensitive to fatigue in multiple sclerosis. METHODS: Structural (magnetic resonance imaging with assessment of thalamic volume and cortical thickness of the primary sensorimotor areas) and functional (cortico-muscular coherence (CMC) from simultaneous electroencephalo- and surface electromyographic recordings during a weak handgrip task) measures were used on 20 mildly disabled MS patients (relapsing-remitting course, Expanded Disability Status Scale score ≤ 2) who were recruited in two fatigue-dependent groups according to the Modified Fatigue Index Scale (MFIS) score. RESULTS: The two groups were similar in terms of demographic, clinical and imaging features, as well as task execution accuracy and weariness. In the absence of any fatigue-dependent brain and muscular oscillatory activity alterations, CMC worked at higher frequencies as fatigue increased, explaining 67% of MFIS variance (p=.002). CONCLUSION: Brain-muscle functional connectivity emerged as a sensitive marker of phenomena related to the origin of MS fatigue, impacting central-peripheral communication well before the appearance of any impairment in the communicating nodes.

SERS assisted sandwich immunoassay platforms for ultrasensitive and selective detection of human Thyroglobulin.

We developed an immunoassay platform for the detection of human Thyroglobulin (Tg) to be integrated with fine-needle aspiration biopsy for early detection of lymph node metastases in thyroid cancer patients. The sensing platform detects Tg by a sandwich immunoassay involving a self-assembled surface-enhanced Raman scattering (SERS) substrate assisted by functionalized gold nanoparticles that provide additional Raman signal amplification and improved molecular specificity. Specifically, the SERS-active substrates were functionalized with Tg Capture antibodies and fabricated either on-chip or on optical fiber tips by nanosphere lithography. Gold nanoparticles were functionalized with Detection antibodies and conjugated with 4-mercaptobenzoic acid, which serves as a Raman reporter. The sandwich assay platform was validated in the planar configuration and a detection limit as low as 7 pg/mL was successfully achieved. Careful morphological examination of the SERS substrates before and after Tg measurements further assessed the effective capture of nanoparticles and correlated the average nanoparticle coverage with the Tg concentration obtained by SERS measurements. The sandwich assay was successfully demonstrated on washout fluids of fine needle aspiration biopsies from cancer patients and confirmed the high specificity of the proposed methodology when complex biological matrices are considered. Finally, SERS optrodes were fabricated and successfully used to detect Tg concentration by applying the same bio-recognition strategy and Raman interrogation through an optical fiber. This opens the possibility of transferring the Tg detection approach to the optical fiber tip to develop point-of-care platforms that can be directly integrated into fine needle aspiration biopsies.

Global cardiovascular risk management in different Italian regions: an analysis of the Evaluation of Final Feasible Effect of Control Training and Ultra Sensitisation (EFFECTUS) educational program.

BACKGROUND AND AIM: The Final Evaluation Feasible Effect of Ultra Control Training and Sensitization (EFFECTUS) is an educational program, aimed at improving global CV risk stratification and management in Italy. The present study evaluates differences on clinical approach to global CV risk among physicians involved in the EFFECTUS program and stratified in three geographical macro-areas (North, Center, South) of our Country. METHODS AND RESULTS: Physicians were asked to submit data already available in their medical records, covering the first 10 adult outpatients, consecutively seen in the month of May 2006. Overall, 1.078 physicians (27% females, aged 50 ± 7 years) collected data of 9.904 outpatients (46.5% females, aged 67 ± 9 years), among which 3.219 (32.5%) were residents in Northern, 3.652 (36.9%) in Central and 3.033 (30.6%) in Southern Italy. A significantly higher prevalence of major CV risk factors, including obesity, physical inactivity, hypertension and diabetes, was recorded in Southern than in other areas. Accordingly, Southern physicians more frequently prescribed antihypertensive, glucose and lipid lowering agents than other physicians, who paid significantly more attention to life-style changes in their clinical practice. CONCLUSIONS: This analysis of the EFFECTUS study demonstrates a high prevalence of CV risk factors in Italy, particularly in Southern areas, and indicates some important discrepancies in the clinical management of global CV risk among physcians working in different Italian regions.

Impact of physicians' age on the clinical management of global cardiovascular risk: analysis of the results of the Evaluation of Final Feasible Effect of Control Training and Ultra Sensitisation Educational Programme.

AIM: To evaluate the potential impact of physicians' age on global cardiovascular (CV) risk management in the population of the Evaluation of Final Feasible Effect of Ultra Control Training and Sensitisation (EFFECTUS) study. METHODS: Involved physicians were stratified into three age groups (≤ 45, 46-55 and > 55 years), and asked to provide clinical data covering the first 10 adult outpatients, consecutively seen in May 2006. RESULTS: Overall 1078 physicians, among whom 219 (20%) were aged ≤ 45, 658 (61%) between 46 and 55, and 201 (19%) > 55 years, collected data of 9904 outpatients (46.5% female patients, aged 67 ± 9 years), who were distributed into three corresponding groups: 2010 (20%), 6111 (62%) and 1783 (18%), respectively. A higher prevalence of myocardial infarction and stroke was recorded by younger physicians rather than those aged > 46 years. Older physicians frequently recommended life-style changes, whereas a higher number of antihypertensive, antiplatelet, glucose and lipid-lowering prescriptions was prescribed by physicians aged ≤ 45 years. CONCLUSIONS: This analysis of the EFFECTUS study indicates a higher prevalence of vascular diseases among outpatients who were followed by younger physicians, who prescribed a higher number of CV drugs than older physicians. These older physicians have more attitude for prescribing favourable life-style changes than younger physicians.

Life-threatening complications of streptococcal sepsis: a PICU contemporary series.

BACKGROUND: Life-threatening streptococcal sepsis nowadays represents an uncommon event in previously healthy infants and children. Critically ill patients suffering from severe streptococcal sepsis complications may present with pre-antibiotic era clinical pictures and require a timely clinical approach to achieve restitutio ad integrum. RESULTS: We report a series of four patient groups affected by an uncommon life-threatening streptococcal sepsis, each of them exhibiting some distinct features. Streptococcus Agalactiae sepsis was associated with cerebral thrombotic/ischaemic lesions, whereas severe cardiogenic shock was prominent in the Streptococcus Viridans group; Streptococcus Faecalis and ß-hemolytic group A Streptococcus patients mostly reported lung complications. CONCLUSIONS: Previous antibiotic treatments should not delay aggressive treatment in the intensive care setting. Early diagnostic suspicion, as well as appropriate and aggressive treatment provided within an intensive care setting are crucial for the clinical outcome.

Gestational diabetes mellitus: Prevention, diagnosis and treatment. A fresh look to a busy corner.

BACKGROUND: Gestational diabetes mellitus (GDM) is a common pregnancy complication characterized by hyperglycaemia with onset or first recognition during pregnancy. Risk factors include family history of diabetes, previous GDM, genetic predisposition for GDM/type 2 diabetes, insulin resistance conditions such as overweight, obesity and ethnicity. Women with GDM are at high risk for fetal macrosomia, small for gestational age, neonatal hypoglycaemia, operative delivery and caesarean delivery. The aim of this narrative review is to summarize the most recent findings of diagnosis and treatment of GDM in order to underline the importance to promote adequate prevention of this disease, especially through lifestyle interventions such as diet and physical activity. METHODS: The research was conducted using the following electronic databases, MEDLINE, EMBASE, Web of Science, Scopus, ClinicalTrial.gov, OVID and Cochrane Library, including all published randomized and non-randomized studies as well as narrative and systematic reviews. RESULTS: The lack of universally accepted criteria makes the definition of diagnosis and prognosis of this condition difficult. Early diagnosis and glucose blood level control may improve maternal and fetal short and long-term outcomes. Treatment strategies include nutritional interventions and exercise. Medical treatment can be necessary if these strategies are not effective. Moreover, novel non-pharmacologic agents such as myo-inositol seem to be effective and safe both in the prevention and the treatment of GDM. CONCLUSIONS: It is important to promote adequate prevention of GDM. Further studies are needed in order to better define the most appropriate strategies for the clinical management of women affected by GDM.

The ratio between kidney volume and function increases with the progression of nephropathy in Type 2 diabetes.

OBJECTIVE: In Type 2 diabetes, it is not clear if renal size is constantly related to the glomerular filtration rate. In addition, it is not known if kidney volume (KV) is associated with an increased urinary albumin and IgG excretion. METHODS: The relationship between kidney volume, creatinine clearance (CrCl), urinary albumin and IgG excretion in 95 Type 2 diabetic patients with different stages of nephropathy (1 - 4 Stage sec NKDF-QD) was elevated and compared to 85 non-diabetic subjects with similar degree of kidney function. RESULTS: In Type 2 diabetic patients the KV/CrCl ratio was increased, in comparison with the control subjects, from about 15% in Stage 1 to 53% in Stage 4. In T2D subjects, significant correlations were found between KV and urinary albumin excretion (r = 0.665, p < 0.05), and between KV and urinary IgG excretion (r = 0.800, p < 0.001). CONCLUSION: The present study finds that Type 2 diabetic subjects, are characterized by an increased ratio between KV/CrCl, throughout the different progressive stages of nephropathy. In Type 2 diabetes relationships between KV and urinary albumin and between KV and IgG excretion also were found to be significant, suggesting a role for the impaired size selectivity of proteinuria as a possible determinant of KV.

Management of hypertension and stroke prevention: results of the Italian cardiologist survey.

OBJECTIVE: To provide an overview of current habits, priorities, perceptions and knowledge of cardiologists with regard to hypertension and stroke prevention in outpatient practice. METHODS: A sample of 203 cardiologists operating in outpatient clinics and randomly selected amongst members of the largest Italian Outpatient Cardiologist Association were interviewed by e-mail, in April-May 2007. RESULTS: The interviewed cardiologists reported that hypertensive outpatients represent a large percentage of their practice population, in which the clinical priority was blood pressure (BP) reduction. Stroke was identified as the most important event to prevent and it was also perceived as the most preventable hypertension-related cardiovascular event. A remarkably high rate of achieved BP control was reported, to a degree that it is inconsistent with current epidemiological reports and with the relatively low percentage use of combination therapies declared by cardiologists. Additional risk factors, organ damage, diabetes mellitus and atrial fibrillation were consistently reported in hypertensive patients. Among antihypertensive drug classes, a preference for angiotensin-converting enzyme inhibitors has been expressed by the majority of physicians; this choice was generally justified by evidence derived from international trials or by the antihypertensive efficacy of this drug class. CONCLUSIONS: The results confirm the presence of weaknesses in the current services for patients with hypertension, even when being managed by cardiologists. Discrepancies between perceptions and reality, or clinical practice and guideline recommendations are also highlighted. An analysis of these aspects may help to identify current areas of potential improvement for stroke prevention in the clinical management of hypertension in cardiology practice.

Prognosis of isolated acute post-traumatic subdural haematoma.

AIM: Acute subdural haematoma (ASDH) is seldom an isolated lesion and it is difficult to understand the mechanisms which determine the poor prognosis associated to this occurrence. Aim of this study was estimating the outcome of patients with ASDH without any companion lesions by analysing the haematoma volume, its thickness and midline shift. METHODS: Twenty-eight severely head injured patients (Glasgow Coma Scale, GCS =/<8) with isolated unilateral ASDH admitted in intensive care unit (ICU) were retrospectively studied. The haematoma thickness, the midline shift, the ASDH volume were obtained from the first emergency computerized tomography (CT) scan and analysed by a computer assisted programme (Osiris). Patients' outcome was scored according to the Glasgow Outcome Scale (GOS) 6 months after the event. According to their GOS the patients were further divided in 2 groups (favourable outcome: GOS 4-5, poor outcome: GOS 1-2-3). RESULTS: Midline shift ranged from 0 to 19.2 mm; we found a larger midline shift in those patients who died and in patients with severe disability or vegetative state 6 months after the trauma. CONCLUSION: The presence and size of midline shift was a more important determinant of outcome than ASDH volume or its thickness.

Clinical tests of musculoskeletal dysfunction in the diagnosis of cervicogenic headache.

Persistent intermittent headache is a common disorder and is often accompanied by neck aching or stiffness, which could infer a cervical contribution to headache. However, the incidence of cervicogenic headache is estimated to be 14-18% of all chronic headaches, highlighting the need for clear criterion of cervical musculoskeletal impairment to identify cervicogenic headache sufferers who may benefit from treatments such as manual therapy. This study examined the presence of cervical musculoskeletal impairment in 77 subjects, 27 with cervicogenic headache, 25 with migraine with aura and 25 control subjects. Assessments included a photographic measure of posture, range of movement, cervical manual examination, pressure pain thresholds, muscle length, performance in the cranio-cervical flexion test and cervical kinaesthetic sense. The results indicated that when compared to the migraine with aura and control groups who scored similarly in the tests, the cervicogenic headache group had less range of cervical flexion/extension (P=0.048) and significantly higher incidences of painful upper cervical joint dysfunction assessed by manual examination (all P<0.05) and muscle tightness (P<0.05). Sternocleidomastoid normalized EMG values were higher in the latter three stages of the cranio-cervical flexion test although they failed to reach significance. There were no between group differences for other measures. A discriminant analysis revealed that manual examination could discriminate the cervicogenic headache group from the other subjects (migraine with aura and control subjects combined) with an 80% sensitivity.

Functional and structural balances of homologous sensorimotor regions in multiple sclerosis fatigue.

Fatigue in multiple sclerosis (MS) is a highly disabling symptom. Among the central mechanisms behind it, an involvement of sensorimotor networks is clearly evident from structural and functional studies. We aimed at assessing whether functional/structural balances of homologous sensorimotor regions-known to be crucial for sensorimotor networks effectiveness-decrease with MS fatigue increase. Functional connectivity measures at rest and during a simple motor task (weak handgrip of either the right or left hand) were derived from primary sensorimotor areas electroencephalographic recordings in 27 mildly disabled MS patients. Structural MRI-derived inter-hemispheric asymmetries included the cortical thickness of Rolandic regions and the volume of thalami. Fatigue symptoms increased together with the functional inter-hemispheric imbalance of sensorimotor homologous areas activities at rest and during movement, in absence of any appreciable parenchymal asymmetries. This finding supports the development of compensative interventions that may revert these neuronal activity imbalances to relieve fatigue in MS.

Chronic vitamin E administration improves brachial reactivity and increases intracellular magnesium concentration in type II diabetic patients.

Vascular disease accounts for the majority of the clinical complications in diabetes mellitus. As an exaggerated oxidative stress degree has been postulated as the link between diabetes mellitus and endothelial function, a possible positive effect of plasma vitamin E (Vit.E) administration on brachial reactivity could be postulated. Our study aims at investigating the possible effect of chronic Vit.E administration on brachial reactivity, oxidative stress indexes, and intracellular magnesium and calcium content in type II diabetic patients free of diabetic complications. Forty adult, type II diabetic patients were enrolled in the study, which was deigned as a double blind, randomized vs. placebo trial. At baseline all patients underwent the following tests: 1) anthropometric and metabolic examinations, 2) evaluation of oxidative stress indexes, 3) intracellular magnesium and calcium measurements, and 4) determination of arterial compliance and distensibility. Then, all patients were randomly assigned to Vit.E treatment at a dose of 600 mg/day (Evion Forte; n = 20) or placebo (n = 20) over 8 weeks. At the end of this treatment period, a complete reevaluation of the patients was made. Vit.E treatment was associated with a significant improvement in the percent change in brachial artery diameter (P<0.03) and oxidative stress indexes (P< 0.005). In the Vit.E group, the percent change in brachial artery diameter correlated positively with the percent change in oxidative stress indexes (oxidized/reduced glutathione, Trolox-equivalent antioxidant capacity, thiobarbituric acid reaction products, lipid peroxides) and intracellular cation content (magnesium and calcium). After adjustment for age, sex, body mass index, and wait/hip ratio, all of these correlations remained significant (P<0.03 for all). Furthermore, adjusting for glycosylated hemoglobin, plasma total cholesterol, and homeostatic model index, brachial artery diameter was still correlated with the percent change in oxidative stress indexes (P<0.04 for all). Nevertheless, the relationship between the percent change in brachial artery diameter and oxidative stress indexes was no longer significant after adjustment for intracellular Mg and Ca2+. In conclusion, our study demonstrates that chronic administration of Vit.E improves brachial artery reactivity in patients with type II diabetes mellitus. Such an effect seems mediated by a reduction in oxidative stress and a regulation of intracellular calcium and magnesium contents.

The BB-paraoxonase genotype is associated with impaired brachial reactivity after acute hypertriglyceridemia in healthy subjects.

The possible relationship between paraoxonase (PON) gene polymorphism and brachial reactivity in healthy adult subjects in the presence of acute hypertriglyceridemia (HT), as a prooxidant factor, was investigated. In 101 healthy subjects the response to flow- induced vasodilatation was measured before and after Intralipid infusion. In the same subjects the A/B PON polymorphism was detected. The frequency was 0.545 for AA genotype, 0.356 for the AB genotype, and 0.099 for the BB genotype. At baseline all genotype groups had a similar increase in brachial artery diameter and flow. After Intralipid infusion, subjects sharing the BB genotype had a significant decrease vs. baseline values in changes in brachial artery diameter (P for trend < 0.001 vs. the other genotypes), but not in flow. In a subgroup of 55 subjects distributed among the 3 PON genotypes the same study protocol was repeated by buccal nitroglycerine administration to study the endothelium-independent vasodilatation. Again, subjects with the BB genotype had the worse vasodilation (P for trend < 0.001). Furthermore, subjects sharing the BB genotype had the lowest endothelium-independent and -dependent changes in diameter (P for trend < 0.001 vs. the other genotypes) independently of gender ratio, basal plasma triglycerides concentrations, and changes in plasma triglycerides concentrations. In conclusion, our study demonstrates that transient HT decreases vascular reactivity more in subjects with the PON BB genotype than in those with the other PON genotypes.

Multiple vertebral hemangiomas resembling metastases with spinal cord compression.

A 58-year-old woman with spastic paraparesis had bony hemangiomas involving the spine, sacrum, and skull. Multiple bony lesions, paravertebral mass, abnormal serum protein levels, and myelopathy suggested multiple myeloma or metastatic neoplasm. Decompressive laminectomy demonstrated a benign capillary hemangioma.

Histologic findings in motor neuron disease. Relation to clinically determined activity, duration, and severity of disease.

Correlation of 18 histologic variables with age and sex of 24 patients with motor neuron disease (MND), and the duration, severity, and activity of their disease, showed that high density of atrophic fibers correlated with degree of muscle weakness and the worst prognosis and that type I grouping correlated with the best prognosis. Although both type I and type II fibers are involved in the majority of patients with MND, the data suggest that involvement of type I fibers is more important in relation to activity of the disease.

Rate and types of fractures in corticosteroid-treated multiple sclerosis patients.

In a retrospective study of 103 corticosteroid-treated MS patients, the average rate of fracture events was 3.2% of the patients per year over 7.1 (+/- 5.7 SD) years at risk. Fractures of the ribs, pelvis, hip, or vertebrae occurred in 11 patients and became most common 5 years after starting steroids. Relatively high or low cumulative doses of steroids did not correlate predictably with the occurrence of fractures.

Effect of total lymphoid irradiation on functional status in chronic multiple sclerosis: importance of lymphopenia early after treatment--the pros.

To determine whether immunosuppression by total lymphoid irradiation (TLI) slowed deterioration of chronic progressive multiple sclerosis (MS), functional impairment score and blood lymphocyte counts were compared at 6-month intervals through 4 years following treatment of MS patients by either TLI (n = 27) or sham irradiation (n = 21). At each interval, 20 to 30% fewer TLI-treated patients had deteriorated (p less than 0.05 at 6, 12, and 18 months), and the difference in mean functional impairment score between groups became progressively greater (p less than 0.01 at 42 and 48 months). Benefit accrued principally to the 17 TLI-treated patients with absolute blood lymphocyte counts less than 900/mm3 3 months after treatment, whose mean functional impairment score remained within 0.6 units of baseline (p = NS), whereas the ten TLI patients with higher post-treatment lymphocyte counts had progressive deterioration (p less than 0.05 to p less than 0.001 versus TLI-treated patients with lower lymphocyte counts at all intervals except 30 months) and had deteriorated by more than 5 functional scale units by 42 and 48 months. Side effects were minor and complications rare in TLI-treated patients, but one TLI-treated patient developed staphylococcal sepsis. Thus, TLI slows deterioration of chronic progressive MS, with what appears to be enduring benefit through 4 years compartmented to patients with greater induced lymphopenia. Modification of lymphoid irradiation regimens to increase the proportion of MS patients who achieve a favorable degree of lymphopenia and to avert functional hyposplenism may further improve the benefit/risk ratio.