The role of multiparametric magnetic resonance in active surveillance of a low-risk prostate cancer cohort from clinical practice.

INTRODUCTION: Active surveillance (AS) is considered a suitable management practice for those patients with low-risk prostate cancer (PCa). At present, however, the role of multiparametric magnetic resonance imaging (mpMRI) in AS protocols has not yet been clearly established. OUTCOMES: To determine the role of mpMRI and its ability to detect significant prostate cancer (SigPCa) in PCa patients enrolled in AS protocols. MATERIALS AND METHODS: There were 229 patients enrolled in an AS protocol between 2011 and 2020 at Reina Sofía University Hospital. MRI interpretation was based on PIRADS v.1 or v.2/2.1 classification. Demographics, clinical, and analytical data were collected and analyzed. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for mpMRI in different scenarios. We defined SigPCa and reclassification/progression as a Gleason score (GS) ≥ 3 + 4, a clinical stage ≥T2b, or an increase in PCa volume. Kaplan-Meier and log-rank tests were used to estimate progression-free survival time. RESULTS: Median age was 69.02 (±7.73) at diagnosis, with a 0.15 (±0.08) PSA density (PSAD). Eighty-six patients were reclassified after confirmatory biopsy, with a suspicious mpMRI an indication for a clear reclassification and risk-predictor factor in disease progression (p < 0.05). During follow-up, 46 patients were changed from AS to active treatment mainly due to disease progression. Ninety patients underwent ≥2mpMRI during follow-up, with a median follow-up of 29 (15-49) months. Thirty-four patients had a baseline suspicious mpMRI (at diagnostic or confirmatory biopsy): 14 patients with a PIRADS 3 and 20 patients with ≥PIRADS 4. From 14 patients with a PIRADS 3 baseline mpMRI, 29% progressed radiologically, with a 50% progression rate versus 10% (1/10 patients) for those with similar or decreased mpMRI risk. Of the 56 patients with a non-suspicious baseline mpMRI (PIRADS < 2), 14 patients (25%) had an increased degree of radiological suspicion, with a detection rate of SigPCa of 29%. The mpMRI NPV during follow-up was 0.91. CONCLUSION: A suspicious mpMRI increases the reclassification and disease progression risk during follow-up and plays an important role in monitoring biopsies. In addition, a high NPV at mpMRI follow-up can help to decrease the need to monitor biopsies during AS.

Stationary flow driven by non-sinusoidal time-periodic pressure gradients in wavy-walled channels.

The classical problem of secondary flow driven by a sinusoidally varying pressure gradient is extended here to address periodic pressure gradients of complex waveform, which are present in many oscillatory physiological flows. A slender two-dimensional wavy-walled channel is selected as a canonical model problem. Following standard steady-streaming analyses, valid for small values of the ratio ε of the stroke length of the pulsatile motion to the channel wavelength, the spatially periodic flow is described in terms of power-law expansions of ε, with the Womersley number assumed to be of order unity. The solution found at leading order involves a time-periodic velocity with a zero time-averaged value at any given point. As in the case of a sinusoidal pressure gradient, effects of inertia enter at the following order to induce a steady flow in the form of recirculating vortices with zero net flow rate. An improved two-term asymptotic description of this secondary flow is sought by carrying the analysis to the following order. It is found that, when the pressure gradient has a waveform with multiple harmonics, the resulting velocity corrections display a nonzero flow rate, not present in the single-frequency case, which enables stationary convective transport along the channel. Direct numerical simulations for values of ε of order unity are used to investigate effects of inertia and delineate the range of validity of the asymptotic limit ε≪1. The comparisons of the time-averaged velocity obtained numerically with the two-term asymptotic description reveals that the latter remains remarkably accurate for values of ε exceeding 0.5. As an illustrative example, the results of the model problem are used to investigate the cerebrospinal-fluid flow driven along the spinal canal by the cardiac and respiratory cycles, characterized by markedly non-sinusoidal waveforms.

Carotid atherosclerosis in virologically suppressed HIV patients: comparison with a healthy sample and prediction by cardiovascular risk equations.

OBJECTIVES: To compare the prevalence of carotid atherosclerosis in virologically suppressed HIV patients with that of a community sample, and to evaluate the capacity of various cardiovascular risk (CVR) equations for predicting carotid atherosclerosis. METHODS: This was a cross-sectional study with two randomly selected groups: HIV patients from an HIV unit and a control group drawn from the community. Participants were matched by age (30-80 years) and sex without history of cardiovascular disease. Carotid plaque, common carotid intima-media thickness (cc-IMT) and subclinical atherosclerosis (carotid plaque and/or cc-IMT > 75th percentile) were assessed by carotid ultrasound. The Systematic Coronary Risk Evaluation (SCORE), Framingham, REGICOR, reduced Data Collection on Adverse Effects of Anti-HIV Drugs (D:A:D), and COMVIH equations were applied, and their abilities to predict carotid plaque were compared using the area under the curve (AUC). RESULTS: Each group included 379 subjects (77.8% men, age 49.7 years). Duration of antiretroviral therapy was 15.5 years. There were no differences between the groups for carotid plaque (HIV, 33.2%; control, 31.3%), mean cc-IMT (HIV, 0.63 mm; control, 0.61 mm) or subclinical atherosclerosis (HIV, 42.9%; control, 47.9%). Thymidine analogues were independently associated with subclinical atherosclerosis in HIV-infected patients. CVR equations revealed AUCs between 0.715 and 0.807 for prediction of carotid plaque; prediction was better in the control group and did not improve when HIV-adapted scales were used. CONCLUSIONS: The features of carotid atherosclerosis did not differ between the HIV-infected and the control group, although CVR equations were more predictive for carotid plaque in controls than in HIV-infected patients. HIV-specific equations did not improve prediction.

Incubation period of COVID-19: A systematic review and meta-analysis. / Período de incubación de la COVID-19: revisión sistemática y metaanálisis.

BACKGROUND AND OBJECTIVE: The incubation period of COVID-19 helps to determine the optimal duration of the quarantine and inform predictive models of incidence curves. Several emerging studies have produced varying results; this systematic review aims to provide a more accurate estimate of the incubation period of COVID-19. METHODS: For this systematic review, a literature search was conducted using Pubmed, Scopus/EMBASE, and the Cochrane Library databases, covering all observational and experimental studies reporting the incubation period and published from 1 January 2020 to 21 March 2020.We estimated the mean and 95th percentile of the incubation period using meta-analysis, taking into account between-study heterogeneity, and the analysis with moderator variables. RESULTS: We included seven studies (n = 792) in the meta-analysis. The heterogeneity (I2 83.0%, p < 0.001) was significantly decreased when we included the study quality and the statistical model used as moderator variables (I2 15%). The mean incubation period ranged from 5.6 (95% CI: 5.2 to 6.0) to 6.7 days (95% CI: 6.0 to 7.4) according to the statistical model. The 95th percentile was 12.5 days when the mean age of patients was 60 years, increasing 1 day for every 10 years. CONCLUSION: Based on the published data reporting the incubation period of COVID-19, the mean time between exposure and onset of clinical symptoms depended on the statistical model used, and the 95th percentile depended on the mean age of the patients. It is advisable to record sex and age when collecting data in order to analyze possible differential patterns.

Neutron Capture on the s-Process Branching Point

The neutron capture cross sections of several unstable nuclides acting as branching points in the s process are crucial for stellar nucleosynthesis studies. The unstable ^{171}Tm (t_{1/2}=1.92 yr) is part of the branching around mass A∼170 but its neutron capture cross section as a function of the neutron energy is not known to date. In this work, following the production for the first time of more than 5 mg of ^{171}Tm at the high-flux reactor Institut Laue-Langevin in France, a sample was produced at the Paul Scherrer Institute in Switzerland. Two complementary experiments were carried out at the neutron time-of-flight facility (n_TOF) at CERN in Switzerland and at the SARAF liquid lithium target facility at Soreq Nuclear Research Center in Israel by time of flight and activation, respectively. The result of the time-of-flight experiment consists of the first ever set of resonance parameters and the corresponding average resonance parameters, allowing us to make an estimation of the Maxwellian-averaged cross sections (MACS) by extrapolation. The activation measurement provides a direct and more precise measurement of the MACS at 30 keV: 384(40) mb, with which the estimation from the n_TOF data agree at the limit of 1 standard deviation. This value is 2.6 times lower than the JEFF-3.3 and ENDF/B-VIII evaluations, 25% lower than that of the Bao et al. compilation, and 1.6 times larger than the value recommended in the KADoNiS (v1) database, based on the only previous experiment. Our result affects the nucleosynthesis at the A∼170 branching, namely, the ^{171}Yb abundance increases in the material lost by asymptotic giant branch stars, providing a better match to the available pre-solar SiC grain measurements compared to the calculations based on the current JEFF-3.3 model-based evaluation.

Moderate alcohol consumption is associated with increased radiological progression in women, but not in men, with early rheumatoid arthritis: results from the ESPOIR cohort (Étude et Suivi des Polyarthrites Indifférenciées Récentes).

OBJECTIVE: We conducted this study to determine whether alcohol consumption influences radiological progression in early rheumatoid arthritis (RA). METHOD: Patients fulfilling the European League Against Rheumatism/American College of Rheumatology 2010 criteria in the early arthritis cohort ESPOIR (Étude et Suivi des Polyarthrites Indifférenciées Récentes) were included in this study. Alcohol consumption was collected at baseline and at each visit. We classified alcohol consumption into three groups: abstinent (0 g/day), moderate (≤ 20 g/day for women, ≤ 30 g/day for men), and abuse (> 20 g/day for women, > 30 g/day for men). The primary outcome was the occurrence of radiological progression, defined as an increase ≥ 5 points in the total Sharp/van der Heijde score. We investigated whether alcohol consumption is predictive of radiological progression at 1, 3, and 5 years by univariate and multivariate analysis adjusted for age, baseline erosion, rheumatoid factor, anti-citrullinated peptide antibody, smoking status, body mass index, and treatment with leflunomide or methotrexate and biologics. RESULTS: The study included 596 patients. When considering the influence of gender on the interaction between alcohol consumption and radiological progression, we showed a deleterious effect of moderate consumption in women [odds ratio (OR) = 1.73, 95% confidence interval (CI) 1.01; 2.96, p = 0.045] and a trend towards a protective effect of moderate consumption in men (OR = 0.50, 95% CI 0.21; 1.16, p = 0.106) in multivariate analysis. CONCLUSION: Our data suggest a deleterious effect of moderate consumption of alcohol on radiological progression in women, but not in men, with early RA.

Radial scars without atypia in percutaneous biopsy specimens: can they obviate surgical biopsy? / Cicatriz radial sin atipia en biopsia percutánea. ¿Puede evitarse la biopsia quirúrgica?

OBJECTIVE: To evaluate the need for surgical biopsy in patients diagnosed with radial scars without atypia by percutaneous biopsy. MATERIAL AND METHODS: In this retrospective observational study, we selected patients with a histological diagnosis of radial scar in specimens obtained by percutaneous biopsy during an 8-year period. The statistical analysis was centered on patients with radial scar without atypia (we assessed the radiologic presentation, the results of the percutaneous biopsy, and their correlation with the results of surgical biopsy and follow-up) and we added the patients with atypia and cancer in the elaboration of the diagnostic indices. RESULTS: We identified 96 patients with radial scar on percutaneous biopsy; 54 had no atypia, 18 had atypia, and 24 had cancer. Among patients with radial scar without atypia, there were no statistically significant differences between patients who underwent imaging follow-up and those who underwent surgical biopsy (p>0.05). The rate of underdiagnosis for percutaneous biopsy in patients without atypia was 1.9%. The rates of diagnosis obtained with percutaneous biopsy in relation to follow-up and surgical biopsy in the 96 cases were sensitivity 92.3%, specificity 100%, positive predictive value 100%, negative predictive value 97.2%, and accuracy 97.9%. The area under the ROC curve was 0.96 (p<0.001), and the kappa concordance index was 0.95 (p<0.001) CONCLUSIONS: We consider that it is not necessary to perform surgical biopsies in patients with radial scars without atypia on percutaneous biopsies because the rate of underestimation is very low and the concordance between the diagnosis reached by percutaneous biopsy and the definitive diagnosis is very high.

Electronegative LDL induces priming and inflammasome activation leading to IL-1ß release in human monocytes and macrophages.

BACKGROUND: Electronegative LDL (LDL(−)), a modified LDL fraction found in blood, induces the release of inflammatory mediators in endothelial cells and leukocytes. However, the inflammatory pathways activated by LDL(−) have not been fully defined. We aim to study whether LDL(−) induced release of the first-wave proinflammatory IL-1ß in monocytes and monocyte-derived macrophages (MDM) and the mechanisms involved. METHODS: LDL(−) was isolated from total LDL by anion exchange chromatography. Monocytes and MDM were isolated from healthy donors and stimulated with LDL(+) and LDL(−) (100 mg apoB/L). RESULTS: In monocytes, LDL(−) promoted IL-1ß release in a time-dependent manner, obtaining at 20 h-incubation the double of IL-1ß release induced by LDL(−) than by native LDL. LDL(−)-induced IL-1ß release involved activation of the CD14-TLR4 receptor complex. LDL(−) induced priming, the first step of IL-1ß release, since it increased the transcription of pro-IL-1ß (8-fold) and NLRP3 (3-fold) compared to native LDL. Several findings show that LDL(−) induced inflammasome activation, the second step necessary for IL-1ß release. Preincubation of monocytes with K+ channel inhibitors decreased LDL(−)-induced IL-1ß release. LDL(−) induced formation of the NLRP3-ASC complex. LDL(−) triggered 2-fold caspase-1 activation compared to native LDL and IL-1ß release was strongly diminished in the presence of the caspase-1 inhibitor Z-YVAD. In MDM, LDL(−) promoted IL-1ß release, which was also associated with caspase-1 activation. CONCLUSIONS: LDL(−) promotes release of biologically active IL-1ß in monocytes and MDM by induction of the two steps involved: priming and NLRP3 inflammasome activation. SIGNIFICANCE: By IL-1ß release, LDL(−) could regulate inflammation in atherosclerosis.

Non-nutritive sucking habits and their effects on the occlusion in the deciduous dentition in children.

AIM: The study evaluated the presence of non-nutritive sucking habits and and their effects on the occlusion in the deciduos dentition in Spanish children. MATERIALS AND METHODS: Study design: Cross-sectional survey. A clinical examination was performed by an experienced examiner in 275 children aged 3 to 6 years and the collected data included the presence of anterior open bite (vertical dimension), unilateral or bilateral posterior crossbite (transverse dimensions), midline deviation and sagittal relationships between incisors, molars and canines. In addition, the parents of each child completed a questionnaire about oral habits. Data analysis included descriptive statistics (frequency distribution). Statistical significance for the association between the non-nutritive sucking habits and development of malocclusion was determined using Chi-square and Fisher's exact tests. Multiple logistic regression analysis was used in order to adjust the results for confounding effects of non-nutritive habits before assessing statistical significance. RESULTS: Non-nutritive sucking habit was observed in 224 children (81.5%) and malocclusions were present in 152 children (55.2%). There were significant relationships between pacifier sucking habit and transverse dimension alteration (OR= 3.29, CI: 0.97- 11.17, p=0.044), midline deviation (OR= 3.00, CI: 1.22-7.38, p=0.013). Children with a history of finger sucking (or thumb sucking) had an increased risk of malocclusion 4.25 times higher (CI: 0.92-19.58, p=0.044) and there was a significant relationship between finger sucking and vertical relationship (OR= 8.25, CI: 2.50-27.25, p=0.001). Children with non- nutritive sucking habits had an increased risk of malocclusion 2.55 higher compared to those without non-nutritive sucking habits (p=0.004). CONCLUSION There was an impact of non-nutritive sucking habit and development of malocclusions in this sample of children.

Effect of 3 Weeks Use of Compression Garments on Stride and Impact Shock during a Fatiguing Run.

Excessive and prolonged exposure to impact acceleration during running is associated with increased injury rate. Acute use of compressive garments has been speculated to improve attenuation. However, it is unknown how longer interventions of compressive garments influence attenuation in running. 40 runners trained with compressive and placebo stockings for 3 weeks. Perception of comfort, stride parameters (rate, length) and impact acceleration (head and tibial peak acceleration, magnitude, acceleration rate and attenuation) were measured every 5 min during a fatigue run (30 min at 80% of the individual's maximal aerobic speed). Compressive stockings reduced tibial peak acceleration and magnitude compared to placebo stockings at every minute (p<0.05) except for the initial measurement (p>0.05). Moreover, compressive stockings led to a lower rate of increase in tibial peak acceleration (14%, p<0.005) and magnitude (16%, p<0.001) as a result of the development of fatigue compared to placebo stockings (24% and 26% increase, p=0.014 and p=0.003, respectively). Similar perception of comfort was reported for both garments. Training with compressive stockings for 3 weeks reduced impact acceleration and the rate of increase in acceleration compared to placebo stockings. These findings suggest that compressive stockings may play a protective role by reducing impact accelerations during running.

Effects of graduated compression stockings on skin temperature after running.

High skin temperatures reduce the thermal gradient between the core and the skin and they can lead to a reduction in performance and increased risk of injury. Graduated compression stockings have become popular among runners in the last years and their use may influence the athlete's thermoregulation. The aim of this study was to investigate the effects of graduated compression stockings on skin temperature during running in a moderate indoor environment. Forty-four runners performed two running tests lasting 30min (10min of warm-up and 20min at 75% of their maximal aerobic speed) with and without graduated compressive stockings. Skin temperature was measured in 12 regions of interest on the lower limb by infrared thermography before and after running. Heart rate and perception of fatigue were assessed during the last minute of the running test. Compression stockings resulted in greater increase of temperature (p=0.002 and ES=2.2, 95% CI [0.11-0.45°C]) not only in the body regions in contact (tibialis anterior, ankle anterior and gastrocnemius) but also in the body regions that were not in contact with the garment (vastus lateralis, abductor and semitendinosus). No differences were observed between conditions in heart rate and perception of fatigue (p>0.05 and ES<0.8). In conclusion, running with graduated compression stockings produces a greater increase of skin temperature without modifying the athlete's heart rate and perception of fatigue.

Influence of foot orthosis customisation on perceived comfort during running.

Although running is associated with many health benefits, it also exposes the body to greater risk of injury. Foot orthoses are an effective strategy to prevent such injuries. Comfort is an essential element in orthosis design since any discomfort alters the runner's biomechanics, compromising performance and increasing the risk of injury. The present study analyses the perceived comfort of three types of orthoses: custom-made, prefabricated and original running shoe insoles. Nine comfort variables for each insole were assessed in a sample of 40 runners. Custom-made and prefabricated insoles were both perceived as significantly more comfortable than the original insoles. The differences were clinically relevant and were potentially causes of modifications in running gait. Although the prefabricated insoles were rated slightly higher than the custom-made insoles, the differences were not statistically significant. This study shows that prefabricated insoles constitute a reasonable alternative to custom-made insoles in terms of comfort. PRACTITIONER SUMMARY: The perceived level of comfort of footwear is considered to be a protective measure of the potential risk of running injuries. We here compared runners' perception of comfort of custom-made and prefabricated orthoses while running. We found that even though custom-made orthoses are closely matched to each individual's foot, such customisation does not necessarily imply greater comfort.

Bradycardia in frontotemporal dementia.

INTRODUCTION: Numerous regions of the brain, such as the medial frontal cortex, orbitofrontal cortex, insula, and amygdala, participate in the autonomic control of cardiovascular functions such as heart rate. The degenerative process in frontotemporal dementia (FTD) involves the listed anatomical structures and may therefore produce dysautonomic cardiovascular symptoms. AIM: To observe whether or not non-cardiogenic bradycardia was more frequent in a group of patients with FTD than in subjects with mild cognitive impairment or dementia of a different aetiology. PATIENTS AND METHOD: Once patients with primary cardiac arrhythmia were excluded, we registered the heart rates of 258 patients with cognitive symptoms (36 with FTD, 22 with Alzheimer disease, 23 with vascular dementia, 10 with other dementias, and 167 with non-dementia cognitive impairment). RESULTS: Bradycardia (<60 beats/minute) was significantly more frequent in patients with FTD. This difference remained significant after excluding subjects undergoing treatment with a potentially bradycardic effect. Bradycardia was more prevalent in behavioural FTD cases than in cases of the aphasic variant, and we detected a trend toward higher frequency among patients with more pronounced right hemisphere atrophy. Moreover, mean systolic blood pressure in FTD patients was lower than in other participants, and systolic hypotension (<120 and <100mm Hg) was more prevalent. CONCLUSION: Bradycardia was more frequent in the FTD sample than in other patients with cognitive symptoms. Further investigations will be necessary before we may consider bradycardia to be a sign supporting diagnosis of FTD or its behavioural variant.

Effect of audiovisual distraction on children's behaviour, anxiety and pain in the dental setting.

AIM: To evaluate whether the parental perception of the patient's anxiety, children's anxiety, pain, behaviour and heart rate of paediatric patients improves when an audiovisual technique is used as a distraction method during dental treatment. MATERIALS AND METHODS: This non-randomised crossover trial was performed with 34 patients aged 6-8 years, who required a minimum of two treatment visits for restorative therapy. During the last visit, the patient was shown a cartoon film. RESULTS: There was a significant improvement in the global behaviour when children were shown a cartoon film (P < 0.001). A significant increase in heart rate was recorded in both visits (P = 0.0001) when the anaesthetic was injected. A 97% of the sample would like to continue seeing their chosen film during subsequent visits. No statistically significant differences were found (P > 0.05) between the visits in terms of parental perception of the patient's anxiety, or the patient's self-reported anxiety, pain and heart rate. CONCLUSIONS: The use of the audiovisual material used as a method of distraction produces a global improvement in patient behaviour, but not in parental perception of the patient's anxiety, self-reported anxiety, pain or heart rate according to the measurement scales used. This material is also highly accepted by paediatric patients.

Effect of switch from flash glucose monitoring to flash glucose monitoring with real-time alarms on hypoglycaemia in people with type 1 diabetes mellitus.

We aimed to evaluate the utility of the FreeStyle Libre 2 device for reducing time below range level 1 and level 2 compared with the Freestyle Libre device (without alarms) in people with type 1 diabetes mellitus. We conducted longitudinal observational follow-up study of a cohort of 100 people with type 1 diabetes mellitus who had switched from FreeStyle Libre to FreeStyle Libre 2 as part of routine clinical practice. Three months after switching to FreeStyle Libre 2, compared with results with FreeStyle Libre, there were a significant improvements in time below range level 1 (p = 0.02) and level 2 (p <0.001), time in range (p <0.001), time above range level 1 (p = 0.002), glucose management indicator (p= 0.04) and mean glucose (p= 0.04) during follow-up. Furthermore there was a significant direct association between age and change in TIR with a coefficient of 0.23, and a significant inverse association between age and change in TAR-1 with a coefficient of 0.11. Switching to a flash glucose monitoring system with alarms improves time below range, time in range and coefficient of variation in people with type 1 diabetes mellitus.

Effects of buoyancy on the dispersion of drugs released intrathecally in the spinal canal.

This paper investigates the transport of drugs delivered by direct injection into the cerebrospinal fluid (CSF) that fills the intrathecal space surrounding the spinal cord. Because of the small drug diffusivity, the dispersion of neutrally buoyant drugs has been shown in previous work to rely mainly on the mean Lagrangian flow associated with the CSF oscillatory motion. Attention is given here to effects of buoyancy, arising when the drug density differs from the CSF density. For the typical density differences found in applications, the associated Richardson number is shown to be of order unity, so that the Lagrangian drift includes a buoyancy-induced component that depends on the spatial distribution of the drug, resulting in a slowly evolving cycle-averaged flow problem that can be analysed with two-time scale methods. The asymptotic analysis leads to a nonlinear integro-differential equation for the spatiotemporal solute evolution that describes accurately drug dispersion at a fraction of the cost involved in direct numerical simulations of the oscillatory flow. The model equation is used to predict drug dispersion of positively and negatively buoyant drugs in an anatomically correct spinal canal, with separate attention given to drug delivery via bolus injection and constant infusion.

An analytic model for the flow induced in syringomyelia cavities.

A simple two-dimensional fluid-structure-interaction problem, involving viscous oscillatory flow in a channel separated by an elastic membrane from a fluid-filled slender cavity, is analyzed to shed light on the flow dynamics pertaining to syringomyelia, a neurological disorder characterized by the appearance of a large tubular cavity (syrinx) within the spinal cord. The focus is on configurations in which the velocity induced in the cavity, representing the syrinx, is comparable to that found in the channel, representing the subarachnoid space surrounding the spinal cord, both flows being coupled through a linear elastic equation describing the membrane deformation. An asymptotic analysis for small stroke lengths leads to closed-form expressions for the leading-order oscillatory flow, and also for the stationary flow associated with the first-order corrections, the latter involving a steady distribution of transmembrane pressure. The magnitude of the induced flow is found to depend strongly on the frequency, with the result that for channel flow rates of non-sinusoidal waveform, as those found in the spinal canal, higher harmonics can dominate the sloshing motion in the cavity, in agreement with previous in vivo observations. Under some conditions, the cycle-averaged transmembrane pressure, also showing a marked dependence on the frequency, changes sign on increasing the cavity transverse dimension (i.e. orthogonal to the cord axis), underscoring the importance of cavity size in connection with the underlying hydrodynamics. The analytic results presented here can be instrumental in guiding future numerical investigations, needed to clarify the pathogenesis of syringomyelia cavities.

Recommendations for the use of in vitro methods to detect specific immunoglobulin E: are they comparable?

Total and specific immunoglobulin (Ig) E can be detected in vitro using several commercially available methods. The largest share of the global market for these methods is held by the ImmunoCAP technique (Thermo Fisher, previously Phadia), Immulite (Siemens), and Hytec-288 (Hycor). Most comparative studies examine Immulite and ImmunoCAP, which differ methodologically but use similar units of measurement relative to the same standard of total IgE (WHO IgE Standard 75/502). Despite their similarity, these kits differ in their quantification of specific IgE, which varies depending on the allergen studied.Thus, specific IgE results obtained with ImmunoCAP and Immulite are not interchangeable. It is important to bear this in mind, especially when determining cutoff points as predictors of a response to oral challenge with specific food allergens. The method used in practice must be the same as the one in the publication guiding clinical decision making. We analyze differences between ImmunoCAP and ISAC microarray, 2 methods from the same manufacturer used to detect IgE to specific proteins (purified or recombinant).The results show that the IgE values obtained with ImmunoCAP are not equivalent to the corresponding values obtained with the ISAC microarray system.

Clinical value of morphine, pholcodine and poppy seed IgE assays in drug-abusers and allergic people.

BACKGROUND: The diagnosis of anaphylactic reactions due to opiates during anaesthesia can be difficult, since in most cases various drugs may have been administered. Detection of specific IgE to poppy seed might be a marker for sensitisation to opiates in allergic people and heroin-abusers. This study assessed the clinical value of morphine, pholcodine and poppy seed skin-prick and IgE determination in people suffering hypersensitivity reactions during anaesthesia or analgesia and drug-abusers with allergic symptoms. METHODS: We selected heroin abusers and patients who suffered severe reactions during anaesthesia and analgesia from a database of 23,873 patients. The diagnostic yield (sensitivity, specificity and predictive value) of prick and IgE tests in determining opiate allergy was analysed. RESULTS: Overall, 149 patients and 200 controls, mean age 32.9 ± 14.7 years, were included. All patients with positive prick to opiates showed positive prick and IgE to poppy seeds, but not to morphine or pholcodine IgE. Among drug-abusers, 13/42 patients (31%) presented opium hypersensitivity confirmed by challenge tests. Among non-drug abusers, sensitisation to opiates was higher in people allergic to tobacco (25%), P<.001. Prick tests and IgE against poppy seed had a good sensitivity (95.6% and 82.6%, respectively) and specificity (98.5% and 100%, respectively) in the diagnosis of opiate allergy. CONCLUSIONS: Opiates may be significant allergens. Drug-abusers and people sensitised to tobacco are at risk. Both the prick and specific IgE tests efficiently detected sensitisation to opiates. The highest levels were related to more-severe clinical profiles.

Self-rated health and mortality: a follow-up study of a Spanish population.

OBJECTIVES: Self-rated health (SRH) is known to be a valid indicator for the prediction of health outcomes. The aims of this study were to describe and analyse the associations between SRH and health status, socio-economic and demographic characteristics; and between SRH and mortality in a Spanish population. STUDY DESIGN: Longitudinal study. METHODS: A sample of 5275 adults (age ≥21 years) residing in the Valencian Community (Spanish Mediterranean region) was surveyed in 2005 and followed for four years. SRH was categorized into good and poor health. The response variable was mortality (dead/alive), obtained from the local mortality register. Logistic regression models were adjusted in order to analyse the associations between SRH and health status, socio-economic and demographic characteristics; odds ratios were calculated to measure the associations. Poisson regression models were adjusted in order to analyse the associations between mortality and explanatory variables; the relative risk of death was calculated to measure the associations. RESULTS: Poor SRH was reported by 25.9% of respondents, and the mortality rate after four years of follow-up was 3.6%. An association was found between SRH and the presence of chronic disease and disability in men and women. A perception of poor health vs good health led to a mortality risk of 3.0 in men and 2.7 in women. SRH was predictive of mortality, even after adjusting for all other variables. In men and women, the presence of disability provided additional predictive ability. CONCLUSIONS: SRH was predictive of mortality in both men and women, and acted as a mediator between socio-economic, demographic and health conditions and mortality.