Case report: Utilizing diffusion-weighted MRI on a patient with chronic low back pain treated with spinal cord stimulation

Diffusion-weighted magnetic resonance imaging (dwMRI) has increasingly demonstrated greater utility in analyzing neuronal microstructure. In patients with chronic low back pain (cLBP), using dwMRI to observe neuronal microstructure can lead to non-invasive biomarkers which could provide clinicians with an objective quantitative prognostic tool. In this case report, we investigated dwMRI for the development of non-invasive biomarkers by conducting a region-based analysis of a 55-year-old male patient with failed back surgery syndrome (FBSS) treated with spinal cord stimulation (SCS). We hypothesized that dwMRI could safely generate quantitative data reflecting cerebral microstructural alterations driven by neuromodulation. Neuroimaging was performed at 6- and 12- months post-SCS implantation. The quantitative maps generated included diffusion tensor imaging (DTI) parameters; fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) computed from whole brain tractography. To examine specific areas of the brain, 44 regions of interest (ROIs), collectively representing the pain NeuroMatrix, were extracted and registered to the patient's diffusion space. Average diffusion indices were calculated from the ROIs at both 6- and 12- months. Regions with >10% relative change in at least 3 of the 4 maps were reported. Using this selection criterion, 8 ROIs demonstrated over 10% relative changes. These ROIs were mainly located in the insular gyri. In addition to the quantitative data, a series of questionnaires were administered during the 6- and 12-month visits to assess pain intensity, functional disability, and quality of life. Overall improvements were observed in these components, with the Pain Catastrophizing Scale (PCS) displaying the greatest change. Lastly, we demonstrated the safety of dwMRI for a patient with SCS. In summary, the results from the case report prompt further investigation in applying dwMRI in a larger cohort to better correlate the influence of SCS with brain microstructural alterations, supporting the utility of dwMRI to generate non-invasive biomarkers for prognostication.

Case report: The promising application of dynamic functional connectivity analysis on an individual with failed back surgery syndrome

Failed back surgery syndrome (FBSS), a chronic neuropathic pain condition, is a common indication for spinal cord stimulation (SCS). However, the mechanisms of SCS, especially its effects on supraspinal/brain functional connectivity, are still not fully understood. Resting state functional magnetic resonance imaging (rsfMRI) studies have shown characteristics in patients with chronic low back pain (cLBP). In this case study, we performed rsfMRI scanning (3.0 T) on an FBSS patient, who presented with chronic low back and leg pain following her previous lumbar microdiscectomy and had undergone permanent SCS. Appropriate MRI safety measures were undertaken to scan this subject. Seed-based functional connectivity (FC) was performed on the rsfMRI data acquired from the FBSS subject, and then compared to a group of 17 healthy controls. Seeds were identified by an atlas of resting state networks (RSNs), which is composed of 32 regions grouped into 8 networks. Sliding-window method and k-means clustering were used in dynamic FC analysis, which resulted in 4 brain states for each group. Our results demonstrated the safety and feasibility of 3T MRI scanning in a patient with implanted SCS system. Compared to the brain states of healthy controls, the FBSS subject presented very different FC patterns in less frequent brain states. The mean dwell time of brain states showed distinct distributions: the FBSS subject seemed to prefer a single state over the others. Although future studies with large sample sizes are needed to make statistical conclusions, our findings demonstrated the promising application of dynamic FC to provide more granularity with FC changes associated with different brain states in chronic pain.

Nanomechanical properties of composite protein networks of erythroid membranes at lipid surfaces

Erythrocyte membranes have been particularly useful as a model for studies of membrane structure and mechanics. Native erythroid membranes can be electroformed as giant unilamellar vesicles (eGUVs). In the presence of ATP, the erythroid membrane proteins of eGUVs rearrange into protein networks at the microscale. Here, we present a detailed nanomechanical study of individual protein microfilaments forming the protein networks of eGUVs when spread on supporting surfaces. Using Peak Force tapping Atomic Force Microscopy (PF-AFM) in liquid environment we have obtained the mechanical maps of the composite lipid-protein networks supported on solid surface. In the absence of ATP, the protein pool was characterized by a Young's Modulus E_pool≈5-15MPa whereas the complex filaments were found softer after protein supramolecular rearrangement; E_fil≈0.4MPa. The observed protein softening and reassembling could be relevant for understanding the mechanisms of cytoskeleton reorganization found in pathological erythrocytes or erythrocytes that are affected by biological agents.

Thermomechanical transitions of egg-ceramide monolayers

Ceramides have unique biophysical properties. Their high melting temperature and their ability to form lateral domains have converted ceramides into the paradigm of rigid lipids. Here, using shear surface rheology of egg-ceramide Langmuir monolayers, a solid to fluid transition was evidenced as a vanishing shear rigidity at lower temperatures than the lipid melting temperature. Such a mechanical transition, which depends on the lipid lateral pressure, was found in a broad range temperature (40-50 °C). The solid to fluid transition was correlated to a LC to LC+LE phase transition, as confirmed by BAM experiments. Interestingly, together with the softening transition, a supercooling process compatible with a glassy behavior was found upon freezing. A new phase scenario is then depicted that broadens the mechanical behavior of natural ceramides. The phase diversity of ceramides might have important implications in their physiological roles.

[Effects of dose of erythropoiesis stimulating agents on cardiovascular outcomes, quality of life and costs of haemodialysis. the clinical evaluation of the DOSe of erythropoietins (C.E. DOSE) Trial]

BACKGROUND

Anaemia is a risk factor for death, adverse cardiovascular outcomes and poor quality of life in patients with chronic kidney disease (CKD). Erythropoietin Stimulating Agents (ESA) are the most used treatment option. In observational studies, higher haemoglobin (Hb) levels (around 11-13 g/dL) are associated with improved survival and quality of life compared to Hb levels around 9-10 g/dL. Randomized studies found that targeting higher Hb levels with ESA causes an increased risk of death, mainly due to adverse cardiovascular outcomes. It is possible that this is mediated by ESA dose rather than haemoglobin concentration, although this hypothesis has never been formally tested.

METHODS

We present the protocol of the Clinical Evaluation of the Dose of Erythropoietins (C.E. DOSE) trial, which will assess the benefits and harms of a high versus a low ESA dose therapeutic strategy for the management of anaemia of end stage kidney disease (ESKD). This is a randomized, prospective open label blinded end-point (PROBE) design trial due to enroll 900 haemodialysis patients. Patients will be randomized 1:1 to 4000 UI/week i. v. versus 18000 UI/week i. v. of epoetin alfa, beta or any other epoetin in equivalent doses. The primary outcome of the trial is a composite of cardiovascular events. In addition, quality of life and costs of these two strategies will be assessed. The study has been approved and funded by the Italian Agency of Drugs (Agenzia Italiana del Farmaco (AIFA)) within the 2006 funding plan for independent research on drugs (registered at www.clinicaltrials.gov (NCT00827021)).

Residues of rotenone, azadirachtin, pyrethrins and copper used to control Bactrocera oleae (Gmel.) in organic olives and oil

Rotenone, azadirachtin, pyrethrins and copper fungicide decay curves were determined in olives and olive oil samples after experimental trials, consisting of one, two and three applications of each active ingredient, were carried out twice in 2005 and 2006. Rotenone, azadiracthin and pyrethrins were analyzed by extraction with acetonitrile and determined by liquid chromatography; copper was extracted into aqueous HCl and determined by chemical stripping. Pyrethrins were always found but in levels below the acceptable limits, whereas rotenone and copper residues always exceeded, after the pre-harvest interval, the maximum threshold allowed for olives. As regards residues in olive oil, rotenone was found in concentrations higher than those detected in olives. Copper accumulated in olives according to the number of applications, whereas, in oil, the residue was always lower than the maximum residue limit. The sensitivity of the method applied did not allow detection of azadirachtin.

Regional brain activation associated with different performance patterns during learning of a complex motor skill

In understanding the brain's response to extensive practice and development of high-level, expert skill, a key question is whether the same brain structures remain involved throughout the different stages of learning and a form of adaptation occurs, or a new functional circuit is formed with some structures dropping off and others joining. After training subjects on a set of complex motor tasks (tying knots), we utilized fMRI to observe that in subjects who learned the task well new regional activity emerged in posterior medial structures, i.e. the posterior cingulate gyrus. Activation associated with weak learning of the knots involved areas that mediate visual spatial computations. Brain activity associated with no substantive learning indicated involvement of areas dedicated to the declarative aspects learning such as the anterior cingulate and prefrontal cortex. The new activation for the pattern of strong learning has alternate interpretations involving either retrieval during episodic memory or a shift toward non-executive cognitive control of the task. While these interpretations are not resolved, the study makes clear that single time-point images of motor skill can be misleading because the brain structures that implement action can change following practice.

Ten year incidence of HCV infection in northern Italy and frequency of spontaneous viral clearance

BACKGROUND

Little is known of the incidence of hepatitis C virus (HCV) infection, and the frequency of spontaneous viral clearance in the general population is unknown. We conducted an epidemiological study in two Apennine towns in northern Italy.

METHODS

Anti-HCV (ELISA and RIBA third generation) and HCV-RNA by polymerase chain reaction were tested in thawed sera from an adult general population of Loiano-Monghidoro in 1986 and 1996, obtained in the context of the MICOL (Multicenter Italian Study on Cholelithiasis). In 1999, anti-HCV positive subjects and sex and age matched controls were recalled in order to identify risk factors for acquiring HCV infection and to assess the family composition of anti-HCV+ subjects.

RESULTS

For 1646 subjects, sera were available from both 1986 and 1996 (mean age in 1986 43 (0.39) years). In 1986, 57 (3.46%) subjects were HCV antibody positive (HCV-Ab+). Eight new cases were recorded in 1996: adult incidence was 50.3 cases/100 000 inhabitants/year. Fifty three of 63 (84.1%) HCV-Ab+ sera were also HCV-RNA+. Genotype 2a/2c accounted for 44% and 1b for 47.0% of cases. HCV-Ab+ subjects had higher serum levels of alanine aminotransferase with respect to controls (p<0.005), as did subjects infected with genotype 1 with respect to those with genotype 2 (p<0.05). Eleven of 65 (16.9%) HCV-Ab+ subjects spontaneously cleared HCV-Ab; 7/11 also lost HCV-RNA- in both serum and leucocytes. Sixteen anti-HCV+ subjects belonged to families containing more than one infected member. Married couples accounted for 10 of these 16 subjects. In four of these five married couples, HCV genotype was identical in the two spouses.

CONCLUSIONS

In rural northern Italy, the adult incidence of HCV is approximately 50 cases/100 000 inhabitants/year. Our findings suggest that as many as 17% of infected subjects may spontaneously clear HCV-Ab. Interfamilial transmission seems to have a role in the spread of infection.

The brain's response to incidental intruded words during focal text processing

The functional neuroanatomy associated with processing single words incidentally, outside focal attention, was investigated. We asked subjects (n = 15) to listen, focus on, and comprehend a story narrative, and then single, unrelated but meaningful words were intruded into the ongoing narrative. We also manipulated the type of intruded word, using either neutral or emotionally valent words, to evaluate the extent of semantic processing and a potential encoding advantage for one type of material. Analyses emphasized the areas of activation unique to the intruded words as distinguished from the narrative text. Subjects were normal, healthy adults (n = 15). Compared to narrative text, the intruded words were associated with activation in the right middle temporal gyrus (BA 39) and posterior cingulate/precuneus regions (BA 30, 23). We conclude that the intruded words did make contact with word-level lexical but not necessarily semantic structures in the middle temporal region. The data suggested that the intruded words were processed by a "nonexecutive" monitoring system implemented by a pairing of activation in posterior, medial structures such as the posterior cingulate with deactivation in brain stem structures. This pattern induced a shift to more passive, less effortful, nonstrategic monitoring of the words. Thus, attention processing, not semantic processing, changes best characterized the brain activation unique to the intruded words. This posterior, medial region is discussed as a substrate dedicated to processing a second, incidental stream of information and thereby providing a crucial mechanism for implementing dual processing of the kind examined here.

Indirect wrist MR arthrography: the effects of passive motion versus active exercise

PURPOSE

In the wrist, to determine whether passive motion or active exercise yields a better indirect MR arthrographic effect following intravenous gadolinium administration.

DESIGN AND PATIENTS

Twenty-six consecutive patients were studied by indirect wrist MR arthrography. In half active exercise and in half passive motion was performed. Four regions of interest were studied including the distal radioulnar joint, the radiocarpal joint, the midcarpal joint, and the triangular fibrocartilage. Ranges and means of signal intensity were calculated. Surgical follow-up was performed in 22 patients.

RESULTS

The joint fluid intensity was greatest in the distal radioulnar joint. Fluid signal intensity was greater and more consistent in the passive motion group although the results did not achieve statistical significance. Imaging accuracy appeared similar in the two groups and was excellent for the triangular fibrocartilage (100%) and scapholunate ligaments (96%).

CONCLUSION

Active exercise and passive motion yield similar degrees of wrist arthrographic effect, but the effect of passive motion is somewhat more consistent. Preliminary data show good accuracy for internal derangements.

[Air pollution and daily mortality in Turin, 1991-1996]

A time series study was carried out to assess the relationship between the air pollutants measured by the air quality monitoring network and daily mortality in Turin, Italy. We used TSP, SO2, NO2, O3, and CO concentrations measured from 1-1-1991 to 31-12-1996 at three stations of the city network, chosen to represent different, typical circumstances of exposure to air pollution in the town. The analysis was performed by robust Poisson regression model including loss smoothing functions to allow for long-time trend, seasons, temperature and relative humidity. Dummy variables for the days of the week and holidays were also included. The relative risk of death for a unit increase in the pollutant concentration either during the same day (lag 0) in the previous ones (lag up to 5) was computed. The unit increase was 50 micrograms/m3 for TSP, SO2, NO2, O3, and 2 mg/m3 for CO. The average daily number of deaths for natural causes was 21. The relative risks for total mortality were 1.04 for TSP (lag 1), 1.10 for SO2 (lag 2), 1.06 for NO2 (lag 1), 1.01 for O3 (lag 0), 1.03 for CO (lag 1). The relative risks were 1.05 for TSP (lag 0), 1.12 for SO2 (lag 2), 1.07 for NO2 (lag 1), 1.03 for O3 (lag 0), 1.03 for CO (lag 1) for cardiovascular mortality, and 1.08 for TSP (lag 2), 1.20 for SO2 (lag 2), 1.12 for NO2 (lag 2), 1.03 for O3 (lag 2), 1.05 for CO (lag 2) for respiratory mortality.

Updating about reductions of air and blood lead concentrations in Turin, Italy, following reductions in the lead content of gasoline

Considering its well-know toxicity and the chronic human exposure to lead, international law-makers enforced some directives or laws calling for the reduction of lead content of gasoline. All of these legislative acts aimed to reduce health risks for the general population. The aim of this study was to consider the effectiveness of these laws on air lead levels and consequently on blood lead levels in a randomly selected urban Italian population. In particular, these markers were analyzed over the course of several years, corresponding to the periods just before and after enforcements of the reductions of lead in petrol. Data presented point out some considerations: (1) enforcement of legislative measures concerning the reduction of lead in petrol has reduced atmospheric levels of lead. This result demonstrates a major environmental success in primary prevention efforts. (2) This success is clear especially considering that the actual Pb-B levels can be extended to the urbanized populations. Pb-B levels were consistently higher for drinkers, for older adults, and for males. The mean of Pb-B level for the present urbanized population is higher than the U.S. overall population (6.4 vs 3 microgram/dl). This difference can be also explained considering the different historical period of enforcement of the restriction laws.

[Compression of the sigmoid of gynecological origin]

The authors report a case of extrinsic stenosis of the sigmoid colon due to inflammation of the uterus and adjoining parts. Attention is drawn to the possibility that the radiological images of this condition may be similar to neoplastic diseases.

[Various air pollutants in Torino]

The trend of concentrations of some pollutants (total particulate, polycyclic aromatic hydrocarbons (PAH), benzo(a)pyrene (BaP), chromium, nickel, lead, vanadium) in the urban air of Turin for the years 1986-87-88 was studied. The air was sampled daily by glass fiber's filters; a ponderal determination of total particulate was made; PAH was dosed by gas-chromatography and by mass spectrometry, metals was determined by atomic absorption spectrometry. These are the values of the three years mean concentration: total particulate 156.3 micrograms/mc, PAH 27.2 ng/mc, B(a)P 2.16 ng/mc, Cr 28.6 ng/mc, Ni 40.5 ng/mc, Pb 1.37 micrograms/mc, V 55.2 ng/mc. Finally, we try to calculate the conjectural carcinogenic effect of the B(a)P for the residents of Turin.

Changes in lung function of children after an air pollution decrease

Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1.0), forced expiratory flow between 25 and 75% of FVC (FEF25-75), and maximal expiratory flow at 50% of FVC (MEF50) were measured in 1,880 school children who lived in urban areas before and after a decrease of air pollution. A group of 162 children from a suburban area served as controls. In the first survey, FEV1.0, FEF25-75, and MEF50 of children from urban areas were significantly lower, while in the second survey they were not significantly different from those of controls. The slopes over time of FEV1.0, FEF25-75, and MEF50, adjusted for sex and anthropometric variables, were closely related to the decrease of pollutants concentration. Our results suggest that a decrease of air pollution may produce an improvement of lung function.

The effects of air pollution on the respiratory health of children: a cross-sectional study

To investigate the effects of air pollution on the respiratory health of children, a subject of some controversy, a comparative study was undertaken of 2,385 school children who lived in central urban, peripheral urban, and suburban areas. Daily monitoring of sulphur dioxide and total suspended particle concentrations in all areas showed that pollutant concentrations in central and peripheral urban areas were above commonly accepted safety levels for respiratory health, while concentrations in the suburban area were within acceptable limits. A questionnaire administered to each mother assessed environmental exposure to pollutants in the household, the occurrence of respiratory symptoms as well as lung diseases as diagnosed by a physician, and general information. Children were interviewed about smoking habits and any acute respiratory symptoms. Children also performed standard lung function tests. Results showed that children from both urban areas had lessened pulmonary function and a higher prevalence of bronchial secretion with common colds than did those from the suburban area. These differences persisted after corrections for exposure to indoor pollutants, active or passive smoking, socioeconomic status, and sex. Parental cigarette smoking was related to a fall in forced expiratory volume in 1 second and an increased incidence of acute respiratory illnesses and chronic cough in children. Although boys had higher lung volumes and lower air flow, regression analysis showed no significant influence of the interactions "sex-geographic area" and "sex-smoking" on lung function. It was concluded that air pollution has a significant effect on the respiratory health of children.

After-hours call in a primary care nursing practice

This paper describes the recorded concerns of clients and the management activity of Master's prepared nurse providers in an urban, ambulatory, university affiliated primary care nursing practice during after-hours call. Retrospective record review was used to collect data. Pain was the most common client concern, and the abdomen the most frequently identified pain site. The majority of concerns expressed by clients were minor health problems appropriate for telephone management. The most frequent interventions used were nursing measures such as comfort, supported and reassurance. Finally, the nurse providers in this group practice managed the majority of calls with nursing interventions.