Air pollution-associated procoagulant changes: the role of circulating microvesicles

BACKGROUND

Epidemiological studies suggest an association between exposure to particulate matter (PM) in air pollution and the risk of venous thromboembolism (VTE).

OBJECTIVES

To investigate the underlying pathophysiological pathways linking PM exposure and VTE.

PATIENTS AND METHODS

We assessed potential associations between PM exposure and coagulation and inflammation parameters, including circulating microvesicles, in a group of 233 patients with diabetes.

RESULTS

The numbers of circulating blood platelet-derived and annexin V-binding microvesicles were inversely associated with the current levels of PM(2.5) or PM(10), measured on the day of sampling. Recent past exposure to PM(10), up to 1 week prior to blood sampling, estimated at the patients' residential addresses, was associated with elevated high-sensitivity C-reactive protein (CRP), leukocytes and fibrinogen, as well as with tissue factor (TF)-dependent procoagulant changes in thrombin generation assays. When longer windows of past exposure were considered, up to 1 year preceding blood sampling, procoagulant changes were evident from the strongly increased numbers of red blood cell-derived circulating microvesicles and annexin V-binding microvesicles, but they no longer associated with TF. Past PM exposure was never associated with activated partial thromboplastin time (aPTT), prothrombin time (PT), or factor (F) VII, FVIII, FXII or D-dimers. Residential distance to a major road was only marginally correlated with procoagulant changes in FVIII and thrombin generation.

CONCLUSIONS

Increases in the number of microvesicles and in their procoagulant properties, rather than increases in coagulation factors per se, seem to contribute to the risk of VTE, developing during prolonged exposure to air pollutants.

Therapeutic challenges in elderly patients with symptomatic hypercalcaemia caused by primary hyperparathyroidism

BACKGROUND

Hypercalcaemia resulting from primary hyperparathyroidism (PHPT) can cause a wide range of symptoms, including cognitive disorders, psychiatric symptoms and muscle weakness. Parathyroid surgery is the only definite cure for PHPT. When surgery is contraindicated or patients decide against it, several non-surgical treatment options are available.

OBJECTIVE

To illustrate the treatment options of symptomatic hypercalcaemia caused by PHPT in the elderly and discuss these options in consideration of the available evidence.

DESIGN

Consecutive case series.

SETTING

University hospital.

PATIENTS

Four older patients aged 79-87 years with symptomatic hypercalcaemia resulting from PHPT.

RESULTS

Three patients had a parathyroid adenoma shown on a sestamibi scan. Normocalcaemia and resolution of symptoms was achieved by different treatment scenarios encompassing forced saline hydration, forced diuresis, intravenous pamidronate and cinacalcet, a calcimimetic drug. In one patient, no parathyroid abnormalities were revealed with imaging. Treatment with cinacalcet resulted in normocalcaemia and a strong improvement of symptoms.

CONCLUSION

In clinical practice, different treatment scenarios are chosen for the treatment of elderly patients with symptomatic hypercalcaemia caused by PHPT. The introduction of cinacalcet offers a new treatment paradigm. We propose to apply cinacalcet preceding elective surgery as an alternative option to standard therapy or as maintenance dose when surgery is not possible.

No exercise-induced increase in serum BDNF after cycling near a major traffic road

Commuting by bike has a clear health enhancing effect. Moreover, regular exercise is known to improve brain plasticity, which results in enhanced cognition and memory performance. Animal research has clearly shown that exercise upregulates brain-derived neurotrophic factor (BDNF - a neurotrophine) enhancing brain plasticity. Studies in humans found an increase in serum BDNF concentration in response to an acute exercise bout. Recently, more evidence is emerging suggesting that exposure to air pollution (such as particulate matter (PM)) is higher in commuter cyclists compared to car drivers. Furthermore, exposure to PM is linked to negative neurological effects, such as neuroinflammation and cognitive decline. We carried-out a cross-over experiment to examine the acute effect of exercise on serum BDNF, and the potential effect-modification by exposure to traffic-related air pollution. Thirty eight physically fit, non-asthmatic volunteers (mean age: 43, 26% women) performed two cycling trials, one near a major traffic road (Antwerp Ring, R1, up to 260,000 vehicles per day) and one in an air-filtered room. The air-filtered room was created by reducing fine particles as well as ultrafine particles (UFP). PM10, PM2.5 and UFP were measured. The duration (∼20min) and intensity of cycling were kept the same for each volunteer for both cycling trials. Serum BDNF concentrations were measured before and 30min after each cycling trial. Average concentrations of PM10 and PM2.5 were 64.9μg/m(3) and 24.6μg/m(3) in cycling near a major ring way, in contrast to 7.7μg/m(3) and 2.0μg/m(3) in the air-filtered room. Average concentrations of UFP were 28,180 particles/cm(3) along the road in contrast to 496 particles/cm(3) in the air-filtered room. As expected, exercise significantly increased serum BDNF concentration after cycling in the air-filtered room (+14.4%; p=0.02). In contrast, serum BDNF concentrations did not increase after cycling near the major traffic route (+0.5%; p=0.42). Although active commuting is considered to be beneficial for health, this health enhancing effect could be negatively influenced by exercising in an environment with high concentrations of PM. Whether this effect is also present with chronic exercise and chronic exposure must be further elucidated.

Appropriate use of interferon beta-1a in multiple sclerosis

Multiple sclerosis (MS), a chronic inflammatory demyelinating disease of the central nervous system, is the most common crippling neurological disease of young adults in the US. The 2 basic clinical forms of the disease (relapsing and progressive), which can occur singly or in combination, encompass a wide range of clinical severities are usually established between 18 and 35 years of age and can persist an entire lifetime. Life expectancy of 20 years is 85% of normal. Historically, the standard proven and generally accepted clinical treatment of the disease has been corticotropin (ACTH) and methylprednisolone, which benefited clinical relapses but had no effect on clinical disability (the most important factor influencing the lives of individual MS patients) or other aspects of the chronic course of the disease. The most important new development in the treatment of MS has been the introduction of interferon beta into the clinic. Two forms of recombinant interferon beta have been approved by the FDA for use in relapsing MS: interferon beta-1b (IFN-beta-1b) and interferon beta-1a (IFN-beta-1a). The efficacy of IFN-beta-1b in the treatment of relapsing-remitting MS was established first but no effect on physical disability progression was discerned. In contrast, well designed trials of intramuscular IFN-beta-1a (Avonex((R))) 6.0 MIU (30micro) weekly and subcutaneous IFN-alpha-1a (Rebif((R))) 6 MIU (22microg) or 12 MIU (44microg) 3 times weekly produced a significant delay in the time to sustained progression in physical disability, the first MS treatment to exert such a prophylactic effect. Additionally, IFN-beta-1a significantly reduced clinical relapses and acute and chronic brain lesions revealed by MRI examinations. It is currently believed that IFN-beta-1a treatment alters the fundamental course of relapsing MS. The mechanisms of the therapeutic benefit of recombinant interferon betas are incompletely understood but may include augmentation of suppressor T cell function, inhibition of interferon gamma actions, inhibition of T cell activation, or induction of interleukin-10 gene transcription.

[Interactions and side-effects of non-steroidal anti-inflammatory drugs]

Non-steroidal anti-inflammatory drugs are often used analgetics in dentistry because of their analgetic and anti-inflammatory effects. Oral health care providers should know their interactions and side-effects meticulously. The automatic prescription of another analgetic just to avoid the side-affects is not always an option, since then the specific properties of NSAID's are missed. A correct patient information, specific medical controls, a combination with other medication or other measures may providefor a safe use of NSAID's. In case of healthy patients younger than 70 years of age and a medication time less than two weeks seldom specific measures are indicated.

Quetiapine as an adjunctive pharmacotherapy for the treatment of non-remitting generalized anxiety disorder: a flexible-dose, open-label pilot trial

BACKGROUND

Generalized anxiety disorder (GAD) is a chronic disorder associated with significant morbidity and disability. Traditional therapies are associated with poor levels of remission, and often result in troublesome side effects.

METHODS

This was a 12-week, open-label, flexible-dose study to assess the efficacy and tolerability of quetiapine as an adjunctive treatment to traditional medication. 40 outpatients with GAD who had not achieved remission following at least 8 weeks of an adequate dose of traditional therapy were enrolled. The primary endpoint was the mean change from pre-treatment to week 12 in the Hamilton Anxiety Rating Scale (HAM-A) total scores. Secondary endpoints included: the proportion of patients achieving remission (HAM-A total score of < or =10 at week 12), Clinical Global Impressions-Severity of Illness (CGI-S), Clinical Global Impressions-Global Improvement (CGI-I), Pittsburgh Sleep Quality Index (PSQI) and Penn State Worry Questionnaire (PSWQ).

RESULTS

Adjunctive quetiapine (mean dose 386mg/day at week 12) significantly reduced the HAM-A total scores from pre-treatment (29.8+/-9.0) to week 12 (9.0+/-10.2) (-20.6; p<0.001). The HAM-A remission rate was 72.1% at week 12. Adjunctive quetiapine resulted in a significant reduction in all efficacy measures by study end. Quetiapine was well tolerated: the most common adverse event (AE) was sedation, with no incidence of serious AEs and no clinically significant changes in vital signs, weight (mean gain 0.5kg at week 12) or laboratory assessments.

CONCLUSION

The results of this small pilot trial suggest that quetiapine adjunctive to traditional therapy may be a useful treatment in patients with GAD or treatment-resistant GAD, and warrant further investigation.

Assessment of coronary heart disease risk in testicular cancer survivors

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Background: Testicular cancer survivors (TCS) who receive cisplatin-based chemotherapy (CBCT) are reported to have an increased risk of coronary heart disease (CHD) compared to chemo-naive TCS (J Clin Oncol 21:1513–1523, 2003). We hypothesized that TCS treated with CBCT would demonstrate abnormal objective measures of future CHD risk compared to chemo-naive TCS. Methods: TCS ≥ 2 years from diagnosis underwent evaluation using established objective measures predictive of future CHD risk: body mass index (BMI), Framingham relative risk (RR), flow-mediated endothelium-dependent vasodilation of the brachial artery (FMD), carotid artery intima-media thickness (IMT), serum intercellular adhesion molecule-1 (ICAM-1), and high sensitivity C-reactive protein (hs-CRP). Data were analyzed using parametric and non-parametric statistics as appropriate. Results: 30 TCS who received CBCT and 20 chemo-naive TCS were recruited. The mean age and time from diagnosis were similar between the 2 groups. Both groups demonstrated elevated BMI, increased Framingham RR, and impaired FMD, consistent with an increased risk of CHD. However, there were no statistically significant differences in these measures between the two groups. Carotid IMT, ICAM-1, and hs-CRP were not significantly abnormal and these measures also did not differ between the two groups. Conclusions: TCS demonstrate abnormal objective measures of CHD risk in both CBCT-treated and chemo-naive groups. These data suggest that behavioral interventions to modify CHD risk should target all TCS independent of chemotherapy status. All values reported are mean ± standard deviation

[Table: see text]

No significant financial relationships to disclose.

Partial breast irradiation (PBI) concurrent with adjuvant dose-dense doxorubicin and dyclophosphamide (ddAC) chemotherapy in early-stage breast cancer: Preliminary safety results from a feasibility trial

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Background: Adjuvant anthracycline-based chemotherapy regimens and radiation therapy as part of breast conservation therapy (BCT) are given sequentially to avoid excessive skin toxicity. PBI employs a shorter course of radiation therapy to a smaller breast field and is the subject of randomized efficacy trials. Concurrent administration of PBI and adjuvant chemotherapy would decrease duration of therapy, allow more women to pursue BCT, improve compliance, and potentially enhance local control. Methods: To examine the feasibility, safety, and short-term risk of recurrence of concurrent PBI with adjuvant ddAC, we are conducting a prospective one-stage, single-arm trial of PBI during the first 2 of 4 cycles of ddAC (60 and 600 mg/m2, respectively) delivered q14d with growth factor support. Patients (pts) with T1–2 N0–1 breast cancer and lumpectomy margins ≥ 3mm are eligible. PBI starts within 3 days of first chemo dose and treats the lumpectomy bed plus margin with 270 cGy fractions × 15 (4050 cGy total). Primary endpoints (skin/soft tissue toxicity and cosmetic outcome) are graded by a panel of physicians using commonly accepted scales. Digital images at baseline, during, and q 3–6 months after PBI are obtained for comparison. Additional chemo and endocrine Rx post ddAC given at the physician’s discretion. We report preliminary safety data. Results: Between 11/04 and 9/05, 10 pts were enrolled and received study therapy (accrual goal = 42); 2 pts also received dd paclitaxel 175 mg/m2 post ddAC. All pts received planned PBI (med. f/u 6 mos, range 3–12 mos). 2 pts missed 1 and 2 cycles of ddAC because of stomatitis (Gr 3) and diverticulitis, respectively. 3 other pts had 1–2 wk chemo delay because of hand-foot syndrome, brief pulmonary syndrome, and febrile neutropenia. No pts developed radiation dermatitis > Gr 1 or radiation recall. All pts had cosmetic outcome grades of good or excellent shortly after completion of therapy. No pts with ≥ 6 mos f/u since PBI had late skin toxicity. Conclusion: Early results suggest that PBI concurrent with ddAC appears feasible and safe. Trial enrolment continues and longer f/u is required. (Funded by The Breast Cancer Research Foundation).

No significant financial relationships to disclose.

Permanent partial phenotypic correction and tolerance in a mouse model of hemophilia B by stem cell gene delivery of human factor IX

Immune responses against an introduced transgenic protein are a potential risk in many gene replacement strategies to treat genetic disease. We have developed a gene delivery approach for hemophilia B based on lentiviral expression of human factor IX in purified hematopoietic stem cells. In both normal C57Bl/6J and hemophilic 129/Sv recipient mice, we observed the production of therapeutic levels of human factor IX, persisting for at least a year with tolerance to human factor IX antigen. Secondary and tertiary recipients also demonstrate long-term production of therapeutic levels of human factor IX and tolerance, even at very low levels of donor chimerism. Furthermore, in hemophilic mice, partial functional correction of treated mice and phenotypic rescue is achieved. These data show the potential of a stem cell approach to gene delivery to tolerize recipients to a secreted foreign transgenic protein and, with appropriate modification, may be of use in developing treatments for other genetic disorders.

Detection of carriers of foot-and-mouth disease virus among vaccinated cattle

To investigate and optimise detection of carriers, we vaccinated 15 calves with an inactivated vaccine based on foot-and-mouth disease virus (FMDV) A Turkey strain and challenged them and two further non-vaccinated calves with the homologous virus four weeks later. To determine transmission to a sensitive animal, we put a sentinel calf among the infected cattle from 60 days post-infection until the end of the experiment at 609 days post-infection. Samples were tested for the presence of FMDV, viral genome, specific IgA antibodies, antibodies against FMDV non-structural (NS) proteins or neutralising antibodies. Virus and viral genome was intermittently isolated from probang samples and the number of isolations decreased over time. During the first 100 days significantly more samples were positive by RT-PCR than by virus isolation (VI), whereas, late after infection more samples were positive by virus isolation. All the inoculated cattle developed high titres of neutralising antibodies that remained high during the entire experiment. An IgA antibody response was intermittently detected in the oropharyngeal fluid of 14 of the 17 calves, while all of them developed detectable levels of antibodies to NS proteins of FMDV in serum, which declined slowly beyond 34 days post-infection. Nevertheless, at 609 days after inoculation, 10 cattle (60%) were still positive by NS ELISA. Of the 17 cattle in our experiment, 16 became carriers. Despite frequent reallocation between a different pair of infected cattle no transmission to the sentinel calf occurred. It remained negative in all assays during the entire experiment. The results of this experiment show that the NS ELISA is currently the most sensitive method to detect carriers in a vaccinated cattle population.

Characterization of changes in the short unique segment of pseudorabies virus BUK-TK900 (Suivac A) vaccine strain

Mutant strains of pseudorabies virus (PRV) of reduced virulence, such as Bartha or BUK-TK900, have been used for vaccination purposes for many years. In contrast to the Bartha strain, BUK-TK900 has not been well characterised at the molecular level. The detailed analysis of this vaccine strain was urged by the fact of the isolation in Poland of field strains which were suspected to originate from BUK-TK900. We characterised changes in the U(S) region of this strain, focusing our attention on gE and gI genes. The only deletion, about 300 bp, found in BamHI 7 fragment (covering most of the U(S) region) was located in the 28 K (US2) gene. BUK-TK 900 produced small plaques on all cell lines tested in our laboratory (SK6, Vero, MDBK, 3T3). The plaque size was restored to about 70% of wild type virus plaque size when growing BUK-TK900 virus on 3T3 complementing cell line expressing PRV gE and up to 100% when cell line producing gE and gI was used. Both gE and gI genes from BUK-TK900 and from some derivative field isolates have been amplified by PCR reaction but no deletions in these genes have been found. Molecular weight of gene products differed from wild type proteins: gE was bigger than wild type gE while gI was smaller. Both proteins were correctly recognised by all tested polyclonal and monoclonal antibodies. Radioimmunoprecipitation study showed that BUK-TK900 gE and gI interact forming a complex. The whole ORF of BUK-TK900 gE was sequenced and only few point mutations were found; only two of them led to changes of amino acids in the polypeptide chain. These were: methionine at position 124 replaced by threonine and glutamine at position 162 replaced by arginine. The introduction of first of these mutations (Met to Thr) to PRV wild type strain NIA-3 resulted in 22% reduction of plaque size. This result confirms the importance of this domain of gE for its function; it was found previously by others that deletion of amino acids 125 and 126 reduced virulence and neurotropism of PRV. More changes were found in BUK-TK900 gI sequence. Over 80% of these changes were located in the terminal 1/3rd of the sequence. Some of these mutations may have significant effect on the secondary structure of gI glycoprotein. The change of the secondary structure may be responsible for the decrease of gI stability and the observed reduction of gI molecular mass.

Screening for multiple sclerosis cognitive impairment using a self-administered 15-item questionnaire

Since there is a need for cost-effective screening techniques to identify neuropsychological impairment in multiple sclerosis (MS) patients, and because existing methods require cognitive testing with subsequent interpretation by a neuropsychologist, a brief self-report procedure was developed to screen for neuropsychological impairment in MS. In the first phase of the study, a pool of 80 items was generated based on a literature review and consultation with healthcare professionals. The set was reduced to 15 via Rasch analysis. Using these items, a brief (five minute) MS Neuropsychological Screening Questionnaire (MSNQ), including patient- and informant-report forms, was composed. In phase II, 50 MS patients and their caregivers completed the MSNQ. A comprehensive neuropsychological test battery was also administered. Analyses covered the reliability of the MSNQ and correlations between both patient- and informant-report scores and objective neuropsychological testing. Cronbach's alpha coefficients were 0.93 and 0.94 for the patient- and informant-report forms, respectively, and both forms of the test were strongly correlated with a more general cognitive complaints questionnaire. The patient MSNQ form correlated significantly with measures of depression but not with objective tests of cognitive function. In contrast, the informant form was correlated with patient cognitive performance but not depression. A cut-off score of 27 on the informant form of the MSNQ optimally separated patients based on a neuropsychological summary score encompassing measures of processing speed and memory. There were two false-negatives and one false-positive, giving the test a sensitivity of 0.83 and a specificity of 0.97. It is concluded, therefore, that this self-administered neuropsychological screening test is reliable and predicts neuropsychological impairment in MS patients with a reasonable degree of accuracy.

Transcallosal bands: a sign of neuronal tract degeneration in early MS?

A pattern of injury observed in patients at high risk for MS described as transcallosal bands (TCB) is hypothesized to be the result of neuronal tract degeneration in earliest MS, extending from typical acute, focal demyelinating lesions located along the lateral borders of the corpus callosum. The TCB, a T2-hyperintense lesion traversing the corpus callosum is recognized on 3-mm thick, T2-weighted imaging, develops over months and persists over years.

Sequence analysis of the membrane protein gene and nucleocapsid gene of porcine reproductive and respiratory syndrome virus isolated from a swine herd in Hungary

Porcine reproductive and respiratory syndrome virus (PRRSV) was isolated from blood samples taken at a pig farm in Hungary from pigs showing clinical signs of the disease. The virus (ABV 32) was identified as belonging to the European genotype by using type-specific monoclonal antibodies. This was confirmed by comparing the sequence of the membrane protein gene (ORF 6) and the nucleocapsid gene (ORF 7) with the American VR2332 and the European LV genotype reference strain, respectively. Analysis of the amino acid sequence of the ORF 6 and ORF 7 of ABV 32 revealed five amino acid changes in both ORFs when compared with LV, of which two changes in ORF 7 were only found in the Spanish isolates. Additionally, the ORF 7 sequence was compared with corresponding sequences of a total of 21 other European strains. Phylogenetic analysis using the PHYLIP package confirmed the close relationship between the Hungarian and the Spanish isolates. Of all the isolates analysed, ABV 32 and LV were the least related.

Personality disorder in multiple sclerosis correlates with cognitive impairment

Previous studies of personality change in multiple sclerosis (MS) relied on brief, nonstandardized assessments or tests that are confounded with symptoms of acute psychiatric disorder. Objectives of the present study were to evaluate character change in MS by using comprehensive trait measures of personality and to determine if there is an association between personality change and cognitive dysfunction. Thirty-four MS patients and 14 healthy volunteers were studied. All underwent comprehensive neurologic and neuropsychologic evaluation. Personality assessments included both self and informant reports on the Hogan Empathy Scale and the NEO Personality Inventory. Abnormalities were found among MS patients indicating elevated neuroticism and reduction in empathy, agreeableness, and conscientiousness. Large patient/informant discrepancies were observed in the MS but not the control group. Three neuropsychological tests emphasizing executive control predicted the presence of these abnormalities; this association suggests a neurogenic, frontal lobe syndrome.

In vivo gene expression revealed by cDNA arrays: the pattern in relapsing-remitting multiple sclerosis patients compared with normal subjects

OBJECTIVES

To use DNA arrays to identify differences in gene expression associated with relapsing-remitting (RR) MS.

METHODS

Total RNA was isolated from monocyte depleted peripheral blood mononuclear cells of 15 RR MS patients and 15 age- and sex-matched controls. The RNA was reverse transcribed to radiolabeled cDNA and the resultant cDNA was used to probe a DNA array containing over 4000 named human genes. The binding of radiolabeled cDNA to the probes on the array was measured by phosphorimager.

RESULTS

Of more than 4000 genes tested, only 34 were significantly different in RR-MS patients from controls. Of these, 25 were significantly increased and 9 significantly decreased in the RR MS patients. Twelve of these genes have inflammatory and/or immunological functions that could be relevant to the MS disease process. The potentially relevant genes that were elevated (15% to 28%) were P protein, LCK, cAMP responsive element modulator, IL-7 receptor, matrix metalloproteinase-19, M130 antigen, and peptidyl-prolyl isomerase. Those that were significantly decreased (15% to 35%) were SAS transmembrane 4 superfamily protein, STRL22 (C-C chemokine receptor 6), AFX protein, DNA fragmentation factor-45 and immunoglobulin gamma 3 (Gm marker).

CONCLUSIONS

The RR-MS disease effect was relatively restricted and most of the mRNAs tested were not different from the normal controls. However, there were significant differences identified in the expression of a subset of mRNAs, including 13 with inflammatory/immune functions that could be relevant to MS. The systematic use of DNA arrays can provide insight into the dynamic cellular pathways involved in MS pathogenesis and its phenotypic heterogeneity.

Rationing medical care: rhetoric and reality in the Oregon Health Plan

The Oregon Health Plan (OHP) has been widely heralded as an important innovation in medical care policy and rationing. Oregon's pioneering method of prioritizing funding for health care through systematic and public ranking of medical services has drawn substantial international interest. This paper reviews the experience of the Oregon plan since it began operation in 1994. We argue that widespread misconceptions persist about the significance of the OHP. In particular, there is little evidence that the OHP has operated as a model of explicit rationing. In reality, Oregon has not rationed services, nor has its policy of cutting public coverage for services produced substantial savings. These findings have important implications regarding the desirability and feasibility of adopting a policy of removing items from the list of insured medicare services in Canada. Oregon's experience suggests that drawing the line on medicare coverage would be more difficult and less financially rewarding than advocates claim.

Fluid-attenuated inversion recovery magnetic resonance imaging detects cortical and juxtacortical multiple sclerosis lesions

BACKGROUND

Autopsy studies showed cortical and juxtacortical multiple sclerosis (MS) plaques. Fluid-attenuated inversion recovery (FLAIR) is an advanced magnetic resonance imaging sequence that reveals tissue T2 prolongation with cerebrospinal fluid suppression, allowing detection of superficial brain lesions.

OBJECTIVES

To assess FLAIR, T1-weighted, and T2-weighted images for detecting lesions in or near the cerebral cortex in patients with MS and to explore the relation between cortical lesions and cortical atrophy.

DESIGN, SETTING, AND PATIENTS

Cross-sectional study in a university MS clinic of 84 patients with MS and 66 age-matched healthy controls receiving 1.5-T fast FLAIR, T2-weighted, and T1-weighted images.

MAIN OUTCOME MEASURES

Regional cortical atrophy was rated vs controls. Cortical and juxtacortical lesions were ovoid hyperintensities involving the cortex and/or gray-white junction.

RESULTS

A total of 810 cortical and juxtacortical lesions were seen by FLAIR in patients (mean, 9.6 per patient), most commonly in the superior frontal lobe. Cortical and juxtacortical lesions were identified in 72 patients and 6 controls. Fourteen percent of cortical and juxtacortical lesions were seen on T1-weighted images and 26% were seen on T2-weighted images. More cortical and juxtacortical lesions were present in secondary progressive disease than relapsing-remitting disease. The total number of cortical and juxtacortical lesions correlated significantly with disease duration and the regional number correlated with the degree of regional atrophy. After taking into account noncortical (white matter) lesions, only the cortical and juxtacortical lesion count predicted atrophy in that region.

CONCLUSIONS

FLAIR can detect many cortical and juxtacortical lesions in MS, which were appreciated previously in autopsy studies but usually missed by magnetic resonance imaging during life. Cortical and juxtacortical plaque formation may contribute to cortical atrophy in MS.

Regional brain atrophy is associated with physical disability in multiple sclerosis: semiquantitative magnetic resonance imaging and relationship to clinical findings

OBJECTIVE

Brain atrophy may occur early in the course of multiple sclerosis (MS) and may be associated with disability. Brain magnetic resonance imaging (MRI) of 114 MS patients (group A) were analyzed for regional atrophy (vs age-/gender-matched controls) and T1 and T2 lesions using 4-point rating systems. Thirty-five separate patients (group B) were analyzed for cortical atrophy (ordinal scale), third ventricular width, and total T2 hyperintense lesion volume (computer assisted). In group A, regression modeling indicated that inferior frontal atrophy (P = .0003) and T2 lesions in the pons (P = .02) predicted physical disability (Expanded Disability Status Scale [EDSS] score). Secondary progressive (SP) versus relapsing patients were predicted by inferior parietal (P = .002), superior parietal (P = .006), temporal (P = .008), inferior frontal (P = .01), superior frontal (P = .01), cerebellum (P = .01), occipital (P = .01), and midbrain (P = .02) atrophy. SP patients were also predicted by total atrophy (P = .01) and third ventricular enlargement (P = .03) but not T1 or T2 lesions. In group B, the regression model predicting EDSS score included only superior frontal atrophy (r = 0.515, P = .002). Mean kappa coefficients of ordinal ratings were 0.9 (intraobserver) and 0.8 (interobserver). Ordinal ratings correlated well with quantitative assessments. The authors conclude that brain atrophy is closely associated with physical disability and clinical course in MS patients and can be appreciated using a semiquantitative MRI regional rating system.

Gray matter T2 hypointensity is related to plaques and atrophy in the brains of multiple sclerosis patients

Cortical and subcortical gray matter hypointensities on T2-weighted MR images (T2WI) occur commonly in MS brains and have been related to disease duration, clinical course, and the level of neurologic disability. These hypointensities have been reported to occur in the thalamus, basal ganglia, and rolandic cortex. We assessed whether T2 hypointensity is associated with the severity of white matter plaques and atrophy of MS brains. In 114 MS patients, hypointensity of the thalamus, putamen, caudate, and sensorimotor cortex was ordinally rated against age- and gender-matched normal controls on 1.5-T MRI fast spin-echo axial T2WI. Regional and global T2 hyperintense and T1 hypointense parenchymal lesion loads were ordinally rated. Enlargement of subarachnoid and ventricular spaces (atrophy) was ordinally rated vs. age- and gender-matched normal controls. T2 hypointensity was highly, positively correlated with many other MRI variables. Regression modeling showed that T2 hypointensity was related to total atrophy, total T2 lesion load, third ventricular enlargement, parietal atrophy, and to a lesser extent, frontal T1 lesions and cerebellar T2 lesions, but not related to gadolinium enhancement. Ordinal ratings of T2 lesions and central atrophy showed high correlations with quantitative computerized assessments. We conclude that gray matter hypointensity on T2WI may reflect pathologic iron deposition and brain degeneration in MS. This T2 hypointensity is associated with brain atrophy and other MR markers of tissue damage. Further study is warranted to determine if T2 hypointensity is predictive of disease course in MS and is a useful surrogate outcome measure in therapeutic trials.

Neuropsychological counseling improves social behavior in cognitively-impaired multiple sclerosis patients

We studied the effectiveness of a newly-developed cognitive-behavioral intervention in 15 patients with marked cognitive impairment and behavior disorder. The design was a single-blind test of a neuropsychological intervention, with pre- and post-treatment assessments of personality and social behavior. MS patients underwent neurological examination and neuropsychological testing at baseline. The patients were then randomly assigned to neuropsychological counseling or standard, non-specific supportive psychotherapy. The active 12-week treatment emphasized enhancement of insight through education, social skills training, and behavior modification. All patients were re-examined within 2 weeks of the termination of treatment. Neuropsychological technicians were blind to treatment condition. Both groups showed evidence of cognitive impairment and personality/behavior disorder prior to treatment and were well matched on demographic, disability, and cognitive measures. Patients who underwent neuropsychological counseling showed significant positive response on measures of social behavior (e.g. excessive ego-centric speech) compared to those who underwent standard counseling. We conclude that these data support the use of non-pharmacological, neuropsychological counseling in patients with acquired, MS-associated behavior disorder.

Prehospital blood transfusion versus crystalloid alone in the air medical transport of trauma patients

INTRODUCTION

Differences in prehospital resuscitation measures and outcomes of trauma patients transported by two air medical programs were assessed comparing the prehospital administration of crystalloid only (Group A) with the administration of 2 liters of crystalloid followed by blood (Group B).

METHODS

A 1-year retrospective review of flight and hospital records of patients taken to Level I trauma centers by two separate air medical programs was completed. Physiologic variables, total fluids infused, and flight times were compared.

RESULTS

Thirty-one patients (Group A) received crystalloids in flight, and 17 patients received in-flight blood (Group B). No statistical differences were found between the two groups when comparing age, ISS, PS, RTS, GCS, survival, and total fluid volume. Group B had statistically greater mean flight times compared with Group A (P < .05). A difference was demonstrated between groups A and B in pH and HCO3 measurements (P < .05), with Group B presenting in a more acidotic state on admission to the hospital.

CONCLUSION

Patients with lengthy flight times, despite the administration of blood products, presented to the trauma center more acidotic than trauma patients receiving only crystalloid. The true impact of blood products on outcome could not be demonstrated because of statistical differences in flight times between the groups. A multicenter study matching flight times, head injury status, and flight type of assess benefit of prehospital utilization of blood products is warranted.

Extended observations on MS patients treated with IM interferon-beta1a (Avonex): implications for modern MS trials and therapeutics

Extended observations of the pivotal phase III clinical trial of interferon-beta1a (IFNbeta1a; Avonex, Biogen) in relapsing MS patients revealed that: (1) active treatment significantly slowed the accumulation of physical disability over time, reduced clinical exacerbations and MRI brain lesions; (2) clinical efficacy did not depend on disability endpoints; (3) active treatment benefited multiple MRI measures of brain lesions; (4) cerebral atrophy occurred over 2 years in relatively mildly disabled patients; and (5) Avonex could slow the development of atrophy after the first year of treatment. Data from this study were recently used to design a new outcome measure for MS clinical trials (the Multiple Sclerosis Functional Composite), and was also the basis for two ongoing studies of IFNbeta1a: one in patients with monosymptomatic onset of MS and the other in secondary progressive MS.

A highly specific and sensitive sandwich blocking ELISA based on baculovirus expressed pseudorabies virus glycoprotein B

A direct sandwich blocking enzyme-linked immunosorbent assay (BacgB ELISA) based on the reaction between a monoclonal antibody (MAb) and a recombinant glycoprotein B (gB) of pseudorabies virus (PRV) was developed. This protein was obtained in large quantities from insect cells infected with a PRV gB recombinant baculovirus. Expression of the gB was confirmed by immunoperoxidase monolayer assay (IPMA) with gB specific MAbs. The specificity and sensitivity of the developed BacgB ELISA were evaluated and compared with two commercially available tests by using sets of sera of known PRV infection or vaccination history. For validation, 347 serum samples have been tested. The BacgB ELISA had a high sensitivity and specificity, which were comparable with those of the two commercial tests. In addition, the BacgB ELISA allows detecting anti-gB antibodies in pig serum as early as 7 days following infection. Also maternal antibodies in uninfected pig sera were detected. We conclude that the BacgB ELISA is a useful tool for the detection of as well vaccinated as infected pigs (including derivatives from gE negative vaccine strains), with the added advantage that it uses an antigen that can be produced safely and in large quantities.

A phase I trial of solubilized DR2:MBP84-102 (AG284) in multiple sclerosis

OBJECTIVE

To assess the safety, tolerability, and biologic and clinical activity of a solubilized complex comprised of human leukocyte antigen-DR2 with myelin basic protein84-102 (AG284)in patients with secondary progressive MS.

BACKGROUND

Soluble species-specific major histocompatibility complex myelin basic protein91-103 complexes ameliorate disease in a dose-dependent manner when administered to SJL/J mice with chronic relapsing experimental allergic encephalomyelitis. Preincubation with AG284 reduces the proliferative response of a DR2-restricted, myelin basic protein84-102-reactive T cell clone, derived from a MS patient, to myelin basic protein84-102 in the presence of autologous antigen-presenting cells.

METHODS

Thirty-three patients with secondary progressive MS were randomly assigned to receive three alternate day IV doses of AG284 or placebo in a double-masked dose escalation study. The primary outcome was safety and tolerability. Secondary outcomes included a comparison of pre- and post-treatment gadolinium-enhanced brain MRI activity, Kurtzke Expanded Disability Status Scale, and Nine Hole Peg Test scores.

RESULTS

The frequency of adverse events was similar in the AG284 and placebo recipients. No significant treatment effect was detected by Expanded Disability Status Scale, Nine Hole Peg Test, or number of new gadolinium-enhancing MRI lesions.

CONCLUSIONS

AG284 as administered during this study was safe and well tolerated. Further studies are warranted to determine the biologic activity and clinical efficacy of this potential treatment for MS.

A Wallerian degeneration pattern in patients at risk for MS

BACKGROUND

Demyelination alone may not explain the progressive disability that frequently develops in MS. An alternative explanation for irreversible disability assumes a contribution from axonal injury or loss. In theory, axonal injury may occur in the focal areas characterized by early inflammation, or can be more distant, as in Wallerian degeneration. However, Wallerian degeneration is thought of as a rare or a late finding in MS.

METHODS

Studies showing a classic Wallerian degeneration pattern in the corticospinal tract were selected from a review of MR studies from patients enrolled in a longitudinal treatment trial. Entry was based on first occurrence of an isolated neurologic syndrome consistent with MS and a positive MRI.

RESULTS

This report is based on five cases followed longitudinally who showed development of a classic T2-hyperintense lesion along the ipsilateral corticospinal tract, subsequent to an initial inciting event located in the white matter located in the superior aspect of the corona radiata. Lesions were evident as T2-hyperintensity persisting throughout the 12 to 18 months of observation.

CONCLUSIONS

This series suggests that Wallerian degeneration, implying axonal injury, may occur as a sequela of acute demyelinating lesions in patients presenting with their first symptoms suggestive of MS. This can produce a component of the increasing burden of T2-hyperintense lesions temporally and spatially dissociated from inflammatory or demyelinating activity. Further studies are required to determine if Wallerian degeneration is an important factor contributing to disability progression in MS.

Detection of pseudorabies virus DNA in individual single-reactor pigs found in certified pseudorabies-free herds

During monitoring of certified pseudorabies (PRV)-free herds to confirm their PRV -free status, occasional individual gE-seropositive pigs are detected. These single-reactor pigs remain gE-seropositive when further serum samples are collected and tested. For the eradication programme to proceed, it is important to determine whether these pigs are only false positives or are; in fact, infected with field PRV. The purpose of this study was to determine whether the polymerase chain reaction (PCR) could detect field PRVDNA in single-reactor pigs and so confirm positive reactions in the serologic monitoring programme. First, DNA samples of various tissues from 15 single-reactor pigs all from different herds were examined for field PRV by PCR. Additionally, serum samples from these pigs were analyzed in a gE-confirmation enzyme linked immunosorbent assay (gE-confirmation ELISA). PCR detected PRVDNA in five of the 15 pigs, and these results were confirmed by the gE-confirmation ELISA. The remaining 10 pigs that tested negative in the PCR also tested negative in the gE- confirmation ELISA. We conclude that PCR can be used to discriminate between true and false serological positive single-reactor pigs and, moreover, that the gE-confirmation ELISA confirms these PCR results.

Use of the brain parenchymal fraction to measure whole brain atrophy in relapsing-remitting MS. Multiple Sclerosis Collaborative Research Group

BACKGROUND

Episodic inflammation in the CNS during the early stages of MS results in progressive disability years later, presumably due to myelin and axonal injury. MRI demonstrates ongoing disease activity during the early disease stage, even in some patients who are stable clinically. The optimal MRI measure for the destructive pathologic process is uncertain, however.

METHODS

In this post-hoc study, MRI scans were analyzed from patients with relapsing MS participating in a placebo-controlled trial of interferon beta-1a. The brain parenchymal fraction, defined as the ratio of brain parenchymal volume to the total volume within the brain surface contour, was used to measure whole brain atrophy. The relationship between disease features and brain atrophy and effect of interferon beta-1a were determined.

RESULTS

MS patients had significant brain atrophy that worsened during each of 2 years of observation. In many patients, brain atrophy worsened without clinical disease activity. Baseline clinical and MRI abnormalities were not strongly related to the rate of brain atrophy during the subsequent 2 years. Treatment with interferon beta-1a resulted in a reduction in brain atrophy progression during the second year of the clinical trial.

CONCLUSIONS

Patients with relapsing-remitting MS have measurable amounts of whole brain atrophy that worsens yearly, in most cases without clinical manifestations. The brain parenchymal fraction is a marker for destructive pathologic processes ongoing in relapsing MS patients, and appears useful in demonstrating treatment effects in controlled clinical trials.

A highly specific and sensitive competitive enzyme-linked immunosorbent assay (ELISA) based on baculovirus expressed pseudorabies virus glycoprotein gE and gI complex

A direct competition enzyme-linked immunosorbent assay (ELISA) based on baculovirus expressed complex of pseudorabies virus (PRV) glycoproteins E (gE) and I (gI) has been developed. For that purpose gE and gI genes of PRV were co-expressed in insect cells. Complex formation was confirmed by radioimmunoprecipitation assay. The specificity and sensitivity of the test were evaluated and compared with an ELISA using only gE as an antigen and a commercially available test. For validation, 245 negative sera and 165 positive sera have been tested. The gE/gI ELISA had a higher sensitivity and specificity when compared with the ELISA using only gE as the antigen. Both sensitivity and specificity were comparable with the commercially available test. Moreover, the test based on the baculovirus gE/gI complex allows the detection of anti-gE antibodies in pig serum as early as two weeks after infection. The gE/gI ELISA test is easy to perform; its additional advantage is that the gE/gI antigen can be produced in baculovirus system in large quantities without handling live pseudorabies virus.

The Oregon Health Plan and the political paradox of rationing: what advocates and critics have claimed and what Oregon did

The article proceeds in three sections. First, we very briefly review the original proposals and ensuing (and misleading) debate over rationing in Oregon. Next, we explore how the politics of rationing unfolded in Oregon from the enactment of OHP to its implementation. Finally, we consider the character of Oregon's innovation and the broader lessons that it holds for reform efforts elsewhere.

Outcome assessment of physiologic and clinical predictors of survival in patients after traumatic injury with a trauma score less than 5

OBJECTIVE

To define those physiologic and clinical variables that have a positive or negative predictive value in discriminating survivors from nonsurvivors with traumatic injuries and a Trauma Score of 5 or less.

METHODS

A retrospective review of 2,622 trauma patients transported by an air medical service from the scene of injury to a Level I trauma center was performed. Demographic, physiologic, and clinical variables were evaluated.

RESULTS

One hundred thirty-six patients were studied; 14 patients survived trauma resuscitation. Survivors had statistically significant improvement in the Glasgow Coma Scale from the field to arrival in the emergency room. Revised Trauma Score, probability of survival, pulse, respiratory rate, cardiac rhythm, central nervous system activity, and signs of life were statistically more favorable in survivors.

CONCLUSION

In patients who survived to discharge, signs of central nervous system activity in the field was a positive predictor of survival, and severe head injury served as a negative predictor of survival.

The chemical control of biofouling in industrial water systems

Oxidising and non-oxidising biocides are commonly used in an attempt to control biofouling in industrial water systems. Many of these programmes, however, fail due to the incorrect selection and application of these chemical compounds. Knowledge of the organisms to be eliminated and system hydraulics are important operational parameters in ensuring the successful application of chemical control programmes. A further complicating factor is the build up of bacterial resistance to many of these compounds. One way of limiting resistance is the alternation of oxidising and non-oxidising biocides at the correct miminum inhibitory concentration and using these in combination with surface active compounds to dislodge any biofilm. A variety of surface monitoring techniques are in use in order to monitor the success of biofouling control programmes. Unfortunately none of these techniques are ideal and results have to be considered very carefully.

Purification and characterization of a flavoprotein involved in the degradation of epoxyalkanes by Xanthobacter Py2

Recently a newly discovered pyridine nucleotide-disulfide oxidoreductase was reported to be essential for the degradation of epoxyalkanes by the Xanthobacter Py2 [Swaving, J., De Bont, J. A. M., Westphal, A. & De Kok, A. (1996) J. Bacteriol. 178, 6644-6646]. The disulfide oxidoreductase has now been purified from propene-grown Xanthobacter Py2. This enzyme (component II) is a NADPH-dependent FAD-containing homodimeric protein. The physiological substrate for this enzyme is unknown. The enzyme was active with the following dithiol substrates in decreasing order: 1,3-propanedithiol, reduced lipoamide and dithiothreitol, and inactive with glutathione and monothiols. In the reversed direction, only activity with 5,5'-dithiobis(2-nitrobenzoate) could be measured. Compared with other disulfide reductases it has a high activity with 5,5'-dithiobis(2-nitrobenzoate) and a low diaphorase and oxidase activity. Steady-state kinetic studies at pH 8.5 with 1,3-propanedithiol show that the enzyme operates by a ternary complex mechanism in the direction of NADP+ reduction. Anaerobic incubation of the enzyme with 1,3-propanedithiol resulted in slow reduction of the enzyme to yield the thiolate-FAD charge-transfer complex, the rate depending on the pH. At pH 7, where reduction was not detectable within 2 h, rapid mixing of NADP+ with the enzyme-propanedithiol mixture resulted in the formation of a complex between the reduced enzyme and NADP+ within the dead time of the instrument (5.6 ms). This is followed by slow formation of NADPH, concomitant with the appearance of the flavin C(4a)-thiol adduct, as judged from the spectral changes. This suggests that the rate-limiting step is the transfer of a hydride ion from the half-reduced enzyme to NADP+. Stopped-flow experiments involving reduction by NADPH show a biphasic behavior. The rapid formation (k(obs) = 40 s(-1)) of a transient intermediate with little absorption decrease at 460 nm and long wavelength absorption was followed by the slow formation (k(obs) = 4 s(-1)) of a species characterized as the thiolate-FAD charge-transfer complex with bound NADP+. Some formation of the FAD C(4a)-thiol adduct was also observed. Photoreduction in the presence of deazaflavin results in rapid bleaching at 450 nm, followed by the slow formation of a stable semiquinone. Full reduction could not be achieved, either by photoreduction or with NADPH, and was incomplete even with dithionite or NADPH in the presence of arsenite. The results indicate a low redox potential of the FAD and a slow rate of electron transfer from the pyridine nucleotide to the redox active disulfide and vice versa. From a sequence alignment with other disulfide reductases, it appears that the active site His-Glu diad is absent in this enzyme. The kinetic and spectral features described above will be discussed in this context.

Selective hepatic arterial embolization of grade IV and V blunt hepatic injuries: an extension of resuscitation in the nonoperative management of traumatic hepatic injuries

BACKGROUND

Recognizing the significant mortality and complications inherent in the operative management of blunt hepatic injuries, hepatic arterial embolization was evaluated as a bridge between operative and nonoperative interventions in patients defined as hemodynamically stable only with continuous resuscitation.

METHODS

Seven of 11 patients with grade IV or V hepatic injuries identified by computed tomography underwent hepatic arterial embolization. A prospective evaluation of hepatic embolization based on subsequent hemodynamic parameters was assessed by matched-pair analysis. A summary of this study population's demographic data and outcomes is presented, including age, Glasgow Coma Scale score, Injury Severity Score, Revised Trauma Score, computed tomography grade, intensive care unit and hospital length of stay, transfusion requirements, complications, and mortality.

RESULTS

No statistical difference was demonstrated between pre-embolization and postembolization hemodynamics and volume requirements. After embolization, however, continuous resuscitation was successfully reduced to maintenance fluids. Hepatic embolization was the definitive therapy for all seven patients who underwent embolization.

CONCLUSION

Results of this preliminary investigation suggest that hepatic arterial embolization is a viable alternative bridging the therapeutic options of operative and nonoperative intervention for a subpopulation of patients with hepatic injury.