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Background: Fatigue is a commonly reported and severe symptom in primary brain tumor patients, but the exact occurrence in meningioma patients is unknown. This study aimed to determine the frequency and severity of fatigue in meningioma patients as well as associations between the level of fatigue and patient-, tumor-, and treatment-related factors. Methods: In this multicenter cross-sectional study, meningioma patients completed questionnaires on fatigue (MFI-20), sleep (PSQI), anxiety and depression (HADS), tumor-related symptoms (MDASI-BT), and cognitive functioning (MOS-CFS). Multivariable regression models were used to evaluate the independent association between fatigue and each patient-, tumor-, and treatment-related factor separately, corrected for relevant confounders. Results: Based on predetermined in- and exclusion criteria, 275 patients, on average 5.3 (SD = 2.0) year since diagnosis, were recruited. Most patients had undergone resection (92%). Meningioma patients reported higher scores on all fatigue subscales compared to normative data and 26% were classified as fatigued. Having experienced a complication due to resection (OR 3.6, 95% CI: 1.8-7.0), having received radiotherapy (OR 2.4, 95% CI: 1.2-4.8), a higher number of comorbidities (OR 1.6, 95% CI: 1.3-1.9) and lower educational level (low level as reference; high level OR 0.3, 95% CI: 0.2-0.7) were independently associated with more fatigue. Conclusions: Fatigue is a frequent problem in meningioma patients even many years after treatment. Both patient- and treatment-related factors were determinants of fatigue, with the treatment-related factors being the most likely target for intervention in this patient population.

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The three-dimensional cardiac monodomain model with inhomogeneous and anisotropic conductivity characterizes a complicated system that contains spatial and temporal approximation coefficients along with a nonlinear ionic current term. These complexities make its numerical modeling computationally challenging, and therefore, the formation of an efficient computational approximation is important for studying cardiac propagation. In this paper, a reduced order modeling approach has been developed for the simplified cardiac monodomain model, which yields a significant reduction of the full order dynamics of the cardiac tissue, reducing the required computational resources. Additionally, the discrete empirical interpolation technique has been implemented to accurately estimate the nonlinearity of the ionic current of the cardiac monodomain scheme. The proper orthogonal decomposition technique has been utilized, which transforms a given dataset called 'snapshots' to a new coordinate system. The snapshots are computed first from the original system, and they encapsulate all the information observed over both time and parameter variations. Next, the proper orthogonal decomposition provides a reduced order basis for projecting the original solution onto a low-dimensional orthonormal subspace. Finally, a reduced set of unknowns of the forward problem is obtained for which the solution involves significant computational savings compared to that for the original system of unknowns. The efficiency of the model order reduction technique for finite difference solution of cardiac electrophysiology is examined concerning simulation time, error potential, activation time, maximum temporal derivative, and conduction velocity. Numerical results for the monodomain show that its solution time can be reduced by a significant factor, with only 0.474 mV RMS error between the full order and reduced dimensions solution.

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We report a case of chyluria caused by Mycobacterium fortuitum infection in a sixty-four year old male, who was successfully treated with two weeks of amikacin, trimethoprim-sulfamethoxazole and levofloxacin followed by twenty four weeks of levofloxacin and doxycycline.

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The automated high-throughput Abbott RealTime MTB real-time PCR assay has been recently launched for Mycobacterium tuberculosis complex (MTBC) clinical diagnosis. This study would like to evaluate its performance. We first compared its diagnostic performance with the Roche Cobas TaqMan MTB assay on 214 clinical respiratory specimens. Prospective analysis of a total 520 specimens was then performed to further evaluate the Abbott assay. The Abbott assay showed a lower limit of detection at 22.5 AFB/ml, which was more sensitive than the Cobas assay (167.5 AFB/ml). The two assays demonstrated a significant difference in diagnostic performance (McNemar's test; P = 0.0034), in which the Abbott assay presented significantly higher area under curve (AUC) than the Cobas assay (1.000 vs 0.880; P = 0.0002). The Abbott assay demonstrated extremely low PCR inhibition on clinical respiratory specimens. The automated Abbott assay required only very short manual handling time (0.5 h), which could help to improve the laboratory management. In the prospective analysis, the overall estimates for sensitivity and specificity of the Abbott assay were both 100 % among smear-positive specimens, whereas the smear-negative specimens were 96.7 and 96.1 %, respectively. No cross-reactivity with non-tuberculosis mycobacterial species was observed. The superiority in sensitivity of the Abbott assay for detecting MTBC in smear-negative specimens could further minimize the risk in MTBC false-negative detection. The new Abbott RealTime MTB assay has good diagnostic performance which can be a useful diagnostic tool for rapid MTBC detection in clinical laboratories.

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OBJECTIVE: The varied presentations and treatments of extremity bone and soft tissue sarcoma mean that the issues faced by survivors are diverse and complex. The aim of this systematic review was to investigate what is known about this topic with a view to identifying areas for further research or service development. METHODS: This was a review of the English language literature identified from Medline and Ovid and hand searches published between January 2000 and September 2012. Results were compiled according to physical, psychological and social domains of survivorship. RESULTS: Of 182 studies identified, 22 met the inclusion criteria. There is a wide range of outcome measures used and a need for more objective measures. Unsurprisingly, survivors of extremity sarcoma typically demonstrate lower levels of physical functioning than healthy controls. In addition, survivors demonstrate a substantial psychological morbidity. CONCLUSIONS: Services for survivors of extremity sarcoma should include rehabilitation and psychological support, sexual health services, expert pain management, and support to return to work.

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RELEVANT LOCAL INJURY EPIDEMIOLOGY: In Hong Kong, there were, on average, about 19 596 traffic crashes involving 157 deaths and 21 106 injured persons each year between 2006 and 2011. Scientific analyses were conducted by geographers and engineers primarily using the police crash database. Medical professionals have been analysing road traffic injury data from hospital discharge summaries. Moreover, community leaders have been trying to promote local safe communities. BEST PRACTICES: This paper describes the effort of a multidisciplinary team to address road safety problems and to sustain road safety benefits through a public health approach. The multidisciplinary team comprised a geographer, an engineer, medical professionals and community leaders. The project covered four tasks, namely data integration, identification of hazardous road locations, crash analysis and engineering study, and knowledge exchange through various activities involving a WHO-designated local safe community. IMPLEMENTATION: The crash and hospital databases for a district in Hong Kong with 500 000 population were integrated. Based on the integrated database, the public health and people-based approach was adopted to identify hazardous road locations--hot zones--using geographical information systems. Specific hot zones having strong patterns of common factors were considered as treatable locations with a combination of low-cost remedial measures. The benefits of the project are sustained through various activities engaging the general public and major stakeholders. RESEARCH AGENDA: More research should be conducted on how institutional support, scientific research and community involvement can be fruitfully combined to achieve the ultimate goal of sustained road safety benefits for people at the community level.

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This paper describes a finite difference neuroelectric modeling software (FNS), written in C and MATLAB, which can be executed as a standalone program or integrated with other packages for electroencephalography (EEG) analysis. The package from the Oxford Center for Functional MRI of the Brain (FMRIB), FMRIB Software Library (FSL), is used to segment the anatomical magnetic resonance (MR) image for realistic head modeling. The EEG electrode array is fitted to the realistic head model using the Bioelectromagnetism MATLAB toolbox. The finite difference formulation for a general inhomogeneous anisotropic body is used to obtain the system matrix equation, which is then solved using the conjugate gradient algorithm. The reciprocity theorem is utilized to limit the number of required forward solutions to N-1, where N is the number of electrodes. Results show that the forward solver only requires 500 MB of random-access memory (RAM) for a realistic 256×256×256 head model and that the software can be conveniently combined with inverse algorithms such as beamformers and MUSIC. The software is freely available under the GNU Public License.

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Currently the resolution of the head models used in electroencephalography (EEG) studies is limited by the speed of the forward solver. Here, we present a parallel finite difference technique that can reduce the solution time of the governing Poisson equation for a head model. Multiple processors are used to work on the problem simultaneously in order to speed up the solution and provide the memory for solving large problems. The original computational domain is divided into multiple rectangular partitions. Each partition is then assigned to a processor, which is responsible for all the computations and inter-processor communication associated with the nodes in that particular partition. Since the forward solution time is mainly spent on solving the associated matrix equation, it is desirable to find the optimum matrix solver. A detailed comparison of various iterative solvers was performed for both isotropic and anisotropic realistic head models constructed from MRI images. The conjugate gradient (CG) method preconditioned with an advanced geometric multigrid technique was found to provide the best overall performance. For an anisotropic model with 256 x 128 x 256 cells, this technique provides a speedup of 508 on 32 processors over the serial CG solution, with a speedup of 20.1 and 25.3 through multigrid preconditioning and parallelization, respectively.

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Mapping the myocardial electric field during a defibrillation pulse requires the recording of potential differences between electrodes. The field is then calculated from these quantities and the corresponding calibration matrix. One straightforward calibration technique involves alignment of a known electric field along each of the orthogonal axes of an electrode array and recording the resulting potential differences. However, no results have been reported to support the efficacy of this technique. This study performs a detailed error analysis including a one-to-one comparison to a precision calibration technique, and quantitatively establishes the efficacy of the orthogonal field technique.

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In the spring of 2003, there was an outbreak of the severe respiratory syndrome (SARS) in Hong Kong. Health concerns have thus triggered an increased and predominant use of various types of household cleansing agents such as triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol). However, it has been reported recently that triclosan could be photochemically converted to toxic 2,8-dichlorodibenzo-p-dioxin (2,8-Cl(2)DD) in the environment. It is therefore necessary to develop environmentally friendly methods for the treatment of triclosan. To this end, photocatalytic degradation of triclosan in aqueous solution was conducted using TiO(2) (Degussa P25) under irradiation of UV light (lambda < 365 nm). It was found that triclosan could be degraded by this approach. Hydrogen peroxide was added to enhance the degradation process, and the optimal initial hydrogen peroxide concentration for triclosan degradation was 0.005% (w/v). Product identification indicated that triclosan oxidation occurred at its phenol moiety and yielded quinone and hydroquinone intermediates. The formation of a dichlorophenol intermediate in triclosan degradation suggested bond-breaking of the ether linkage occurred during the process. Moreover, no chlorinated dibenzo-p-dioxin congener was detected. These findings confirm that the photocatalytic degradation of triclosan is an environmentally friendly process.

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The design of a calibrated resistive-network current divider for precision current delivery during transthoracic defibrillation shocks is presented together with test results. The current divider presents a constant 50-ohm load to the defibrillator and thus maintains a constant pulse shape. Current is selected before the shock by setting three rheostats using a computer-generated calibration table. Following each shock, the data acquisition and display software updates the calibration table based on the measured value of transthoracic resistance. Over a range of 15-27 A, the root-mean-square (rms) error for delivered versus selected current was 0.48% for a 45-ohm resistive load, and 0.71% for a 100-ohm load. These test results were confirmed by animal experiments. Over 3 dogs, the rms error was 0.49% from 15-27 A and not greater than 1.5% over the entire 8-44 A range.

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In an earlier study, the authors presented a calibration technique for a triaxial bipolar electrode array (EA) that used 72 data points collected during a global sweep of the electric field vector relative to the EA axes. Although necessary for the initial characterization of the EAs, this data requirement has to be significantly reduced for the technique to become a practical tool. Therefore, in the present study, an analysis is performed to determine the relation between the number of data points used in the calibration and the mean root-mean-square error. The analysis shows that 18 data points can produce results nearly identical to those obtained with the 72-point calibration, thus reducing the required amount of data fourfold.

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Over the past two decades, catatonia, particularly its acutely emerging akinetic-hypokinetic (stuporous) variant, has gradually regained its importance in descriptive psychopathology. Electroconvulsive therapy and lately benzodiazepines are not only effective treatment options in this form of catatonia, but also helped generate neurobiological hypotheses concerning its pathophysiology. Within this broad framework, this paper summarizes the results of recent benzodiazepine treatment response studies in catatonic movement disorders with particular reference to the authors' own studies in Chinese patients with catatonia.

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BACKGROUND: Crack smokers are exposed to a pyrolysis product, methylecgonidine (MEG), which can be used as an analytical marker for crack smoking. Ecgonidine (EC), a hydrolytic product of MEG, has been identified in urine of crack smokers. MEG undergoes conversion to EC, complicating analysis and perhaps explaining a lack of forensic blood specimens containing MEG. METHODS: We developed gas chromatography-mass spectrometry (GC-MS) assays for MEG and EC. Plasma was collected from sheep blood containing 0, 0.06, or 0.24 mol/L (0%, 0.25%, or 1%) NaF. MEG was added to these plasmas, and they were incubated at -80, 1, 21, or 37 degrees C to determine whether there were temporal, temperature, or storage effects on MEG stability over 48 h. RESULTS: Decreased temperature and increased NaF concentrations limited MEG degradation and EC formation. MEG stored in plasma at -80 degrees C was stable up to 1 month, even in the absence of NaF. CONCLUSIONS: MEG is stable in sheep plasma collected in commercially available, evacuated blood-collection tubes containing NaF and stored at -80 degrees C. In vitro formation of EC can be minimized with appropriate sample handling, and its in vivo formation may provide a better marker of crack smoking than its parent pyrolysis product.

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Previously, we have shown that some rheumatoid factors (RFs) produced by Epstein-Barr virus (EBV)-transformed B cells from patients with rheumatoid arthritis (EBV-RA-RF) appear to be disease-specific autoantibodies that bind differently to defined epitopes on genetically engineered IgG antibodies, compared with RFs expressed by patients with Waldenstrom's macroglobulinaemia (Wmac-RFs) and healthy immunized donors (HID-RFs). To exclude the possibility that EBV transformation is responsible for these differences, we have now studied 15 other monoclonal IgM RFs from patients with RA that were produced by heterohybridoma-B-cell fusion (HRA-RFs). These HRA-RFs show the same gross specificity profiles for IgG as do their EBV-RA-RF counterparts. However, when the specificities of the HRA-RF and EBV-RA-RF panels were combined and compared with those RFs from patients with Wmac or HID, significant differences in binding specificity were again observed. Hybrid IgG3/4 antibodies made by exon shuffles between the IgG3 and IgG4 wild-type genes, and families of IgG variant antibodies made by site-directed mutagenesis, were used to map the fine specificity of HRA-RFs. The fine specificity of HRA-RFs were also similar to those of EBV-RA-RFs. These studies demonstrate that the method used for immortalizing IgM, RF-producing B cells from RA patients does not influence the specificity of the RFs obtained. Furthermore, some RFs expressed in RA have distinct and unique specificities, and may therefore represent disease-specific autoantibodies.

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Several methods of drug testing are efficacious in identifying and monitoring drug use during pregnancy. Urine screening remains the most commonly used method despite the limited period during which drugs can be detected. Hair has been recognized as a possible alternate test specimen, but wider acceptance of hair testing must await better understanding of drug disposition in hair, answers to the issues relating to interpretation, and the development of less demanding laboratory techniques. Regardless of the matrix used, proper interpretation of the results of drug testing requires familiarity with the sensitivity, specificity, and limitations of the laboratory methodologies employed. Moreover, unconfirmed positive results may actually be false-positives and must be interpreted with caution, particularly if they are the basis for major clinical decisions.

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Drug testing of patients in a psychiatric outpatient service is an effective way to identify patients who relapse into renewed use of drugs of abuse and in monitoring the effectiveness of ongoing medical and psychological therapy. Most of this testing involves the analysis of urine specimens with immunoassays. Hair testing affords an alternative specimen matrix that is easy to obtain and not readily adulterated and offers the advantage of a wider surveillance window. Hair analysis is technically demanding, and the possibility of false-positives caused by environmental contamination renders it a controversial alternative. Sweat and saliva are potentially useful testing matrices, but their usefulness in clinical practice must await validation by additional clinical and laboratory experience. The correct interpretation of drug test results is predicated on knowing the performance characteristics of the analytical method, route of administration, and pharmacokinetics of the drug. All questionable positive results need confirmation testing to verify true positivity.

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Identification of intrauterine drug-exposed newborns with toxicological screening may have benefits including close follow-up of the infant by both medical and social services. Applying specific written guidelines to select newborns for drug testing decreases bias and protects the physicians and hospitals involved. All drugs reported as positive should be confirmed by an appropriate second test. Urine and meconium testing are the best current options for identifying drug-exposed neonates. Urine testing sensitivity is low because of problems encountered in urine collections and the high thresholds used in current urine assays. The disadvantage to meconium testing is the increased labor and time required to work with this material. Testing of newborn hair is unlikely to be widely used until technically less demanding assays become available. Testing of amniotic fluid or gastric lavage is still in the developmental stages. Adopting lower urine assay thresholds for newborn samples would increase sensitivity and would be an appropriate modification of current methodologies.

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OBJECTIVE: To determine if a program of dietary modification and fish oil supplementation is effective in treating the dyslipoproteinemia in pediatric systemic lupus erythematosus (SLE). METHODS: Prospective clinical trial where each patient serves as his/her own control. Twenty-four consecutive adolescents fulfilling SLE classification criteria were screened with fasting lipid profiles. Patients were identified as having dyslipoproteinemia of active disease or of corticosteroid therapy. Patients were treated for 6 weeks with dietary modification and if dyslipoproteinemia did not normalize with another 6 weeks of dietary modification and fish oil supplementation. RESULTS: Seventeen patients (71%) had dyslipoproteinemia; 10 of active disease, 4 of steroid therapy; 3 with a combined pattern. Eleven patients underwent dietary modification. There was a significant decrease in serum triglyceride concentrations (p < 0.05). Total cholesterol, low density lipoprotein cholesterol, and high density lipoprotein cholesterol did not change significantly. A further significant decline in serum triglycerides was achieved with fish oil supplementation (p < 0.05). Five of the 11 patients who underwent treatment continued to have dyslipoproteinemia. CONCLUSION: Dyslipoproteinemia is common in pediatric SLE. Dietary modification and fish oil supplementation appear to be effective in improving serum lipid profiles, and blinded studies are warranted. a significant number of patients may require pharmacologic therapy for persistent dyslipoproteinemia to prevent complications of premature atherosclerosis.

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We screened anonymously all mothers and infants born during a 3 1/2-month period to determine the prevalence of intrapartum cocaine use, test the maternal characteristics that are specific predictors of intrauterine cocaine exposure (IUCE), and compare the sensitivity of infant urine versus meconium samples for identification of IUCE. Of 1237 live births during the study period, a sample was obtained from 1201 mother-infant pairs. The overall prevalence of documented intrapartum cocaine exposure was 66 (5.5%) of 1201 pairs. Previously developed drug screening guidelines had a sensitivity of 89% for detecting IUCE in infants. Direct comparisons of samples from the same mother-infant pair revealed that there were no cases in which cocaine was found in infant urine but not in meconium; however, infant urine testing missed 25% of the infants who had positive findings in meconium. We conclude that (1) meconium testing was more likely than urine testing to identify an infant with IUCE, detecting an additional 33%; (2) there was significant maternal cocaine use (5.5%) in a teaching hospital with a mixed patient population; (3) maternal characteristics known to identify infants at risk of having IUCE were useful in our population; and (4) IUCE of neonates admitted to the neonatal intensive care unit was more common than that of infants admitted to the regular newborn nursery.

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