Authentication and Authorisation Mechanisms in support of Secure Access to WMN Resources

Over the past several years, a number of design approaches in wireless mesh networks have been introduced to support the deployment of wireless mesh networks (WMNs). We introduce a novel wireless mesh architecture that supports authentication and authorisation functionalities, giving the possibility of a seamless WMN integration into the home's organization authentication and authorisation infrastructure. First, we introduce a novel authentication and authorisation mechanism for wireless mesh nodes. The mechanism is designed upon an existing federated access control approach, i.e. the AAI infrastructure that is using just the credentials at the user's home organization in a federation. Second, we demonstrate how authentication and authorisation for end users is implemented by using an existing web-based captive portal approach. Finally, we observe the difference between the two and explain in detail the process flow of authorized access to network resources in wireless mesh networks. The goal of our wireless mesh architecture is to enable easy broadband network access to researchers at remote locations, giving them additional advantage of a secure access to their measurements, irrespective of their location. It also provides an important basis for the real-life deployment of wireless mesh networks for the support of environmental research.

Approaches to the treatment of hypereosinophilic syndromes: a workshop summary report

Hypereosinophilic syndromes are a heterogeneous group of uncommon disorders characterized by the presence of marked peripheral blood eosinophilia, tissue eosinophilia, or both, resulting in a wide variety of clinical manifestations. Although corticosteroids are the first-line therapy for many of these disorders, approaches to the treatment of patients who do not tolerate or are unresponsive to corticosteroids are poorly standardized. A multidisciplinary group of 37 clinicians and scientists participated in a workshop held in May 2005 in Bern, Switzerland to discuss current and future approaches to therapy for 3 eosinophil-mediated disorders: hypereosinophilic syndrome, Churg-Strauss syndrome, and eosinophil-associated gastrointestinal disease. The goal of the workshop was to summarize available data regarding treatment of these disorders to identify the most promising therapies and approaches for further study. There was consensus among all of the participants that the identification of markers of disease progression to assess treatment responses is a research priority for all 3 disorders. Furthermore, the need for newer therapeutic strategies and novel drugs, as well as multicenter trials to assess all treatment modalities, was emphasized.

Cost-effectiveness of pharmacogenetic testing to predict treatment response to angiotensin-converting enzyme inhibitor

OBJECTIVE: This study aimed to assess the potential cost-effectiveness of testing patients with nephropathies for the I/D polymorphism before starting angiotensin-converting enzyme (ACE) inhibitor therapy, using a 3-year time horizon and a healthcare perspective. METHODS: We used a combination of a decision analysis and Markov modeling technique to evaluate the potential economic value of this pharmacogenetic test by preventing unfavorable treatment in patients with nephropathies. The estimation of the predictive value of the I/D polymorphism is based on a systematic review showing that DD carriers tend to respond well to ACE inhibitors, while II carriers seem not to benefit adequately from this treatment. Data on the ACE inhibitor effectiveness in nephropathy were derived from the REIN (Ramipril Efficacy in Nephropathy) trial. We calculated the number of patients with end-stage renal disease (ESRD) prevented and the differences in the incremental costs and incremental effect expressed as life-years free of ESRD. A probabilistic sensitivity analysis was conducted to determine the robustness of the results. RESULTS: Compared with unselective treatment, testing patients for their ACE genotype could save 12 patients per 1000 from developing ESRD during the 3 years covered by the model. As the mean net cost savings was euro 356,000 per 1000 patient-years, and 9 life-years free of ESRD were gained, selective treatment seems to be dominant. CONCLUSION: The study suggests that genetic testing of the I/D polymorphism in patients with nephropathy before initiating ACE therapy will most likely be cost-effective, even if the risk for II carriers to develop ESRD when treated with ACE inhibitors is only 1.4% higher than for DD carriers. Further studies, however, are required to corroborate the difference in treatment response between ACE genotypes, before genetic testing can be justified in clinical practice.

Differences in the EEG profiles of early and late responders to antipsychotic treatment in first-episode, drug-naive psychotic patients

The aim of this study was to search for differences in the EEG of first-episode, drug-naive patients having a schizophrenic syndrome which presented different time courses in response to antipsychotic treatment. Thirteen patients who fulfilled DSM-IV diagnosis for schizophrenia or schizophreniform disorder participated in this study. Before beginning antipsychotic treatment, the EEG was recorded. On the same day psychopathological ratings were assessed using the ADMDP system, and again after 7 and 28 days of treatment. The resting EEG (19 leads) was subject to spectral analysis involving power values for six frequency bands. The score for the schizophrenic syndrome was used to divide the patients into two groups: those who displayed a clinically meaningful improvement of this syndrome (reduction of more than 30%) after 7 days of treatment (early responders, ER) and those who showed this improvement after 28 days (late responders. LR). Analysis of variance for repeated measures between ER, LR and their matched controls with the 19 EEG leads yielded highly significant differences for the factor group in the alpha2 and beta2 frequency band. No difference was found between the slow-wave frequency bands. Compared to controls the LR group showed significantly higher alpha2 and beta2 power and, in comparison to the ER group, significantly higher alpha2 power. There were no significant differences between the ER and the control group. These findings point to differences in brain physiology between ER and LR. The implications for diagnosis and treatment are discussed.

Percutaneous closure of patent foramen ovale for migraine headaches refractory to medical treatment

BACKGROUND: Patent foramen ovale (PFO) has been linked to migraine, and several retrospective studies reported an improvement in migraine prevalence or frequency after PFO closure for other reasons, mostly for secondary prevention of paradoxical embolism or following diving accidents. We investigated the outcome of patients undergoing PFO closure solely for migraine headaches refractory to medical treatment. METHODS: Seventeen patients (age 44 +/- 12 years; 76% female; one atrial septal aneurysm) underwent percutaneous PFO closure using the Amplatzer PFO Occluder (AGA Medical Corporation, Golden Valley, MN). An 18-mm device was used in two patients, a 25-mm device in 13, and a 35-mm device in two. The interventions were solely guided by fluoroscopy, without intraprocedural echocardiography. RESULTS: All implantation procedures were successful. There were no peri-procedural complications. Contrast transesophageal echocardiography after Valsalva maneuver at 6 months showed complete PFO closure in 16 patients (94%), whereas a minimal residual shunt persisted in one (6%). During 2.7 +/- 1.5 years of follow-up, no deaths and no embolic events occurred. After PFO closure, migraine headaches disappeared in four patients (24%), and improved in eight additional patients (47%). Three patients (18%) reported a decrease of their headaches by 75%, three patients (18%) a decrease of 50%, and two patients (12%) a decrease of 25%, while headaches remained unchanged in five patients (29%). No patient experienced worsening headaches. Moreover, the prevalence of migraine with aura decreased from 82 to 24% (P = 0.002). CONCLUSIONS: These results suggest that percutaneous PFO closure durably alters the spontaneous course of shunt associated migraine.

[Artificial intravascular oxygenation (IVOX). Application to the treatment of postoperative respiratory failure]

Very recently, the concept of artificial intracorporeal oxygenation of blood for patients suffering from respiratory failure has been introduced into clinical practice through development of a totally implantable intravascular oxygenator (IVOX). We report on the use of such a device in a patient who developed severe respiratory insufficiency secondary to prolonged hypovolaemic shock and pneumonia following successful repair of a ruptured abdominal aortic aneurysm in September, 1990. Postoperatively, severe hypoxaemia occurred (AaDO2 548-602 torr) despite extensive mechanical ventilatory support. There was no obvious chance to overcome this situation by conventional therapeutic measures and the decision was made to institute IVOX therapy. Hypoxaemia was resolved immediately and both FiO2 and tidal volume could be reduced within hours. The patient's respiratory condition continued to improve over the next days leading to termination of IVOX therapy after 71 hours. However, the necessity of long-term ventilatory support secondary to recurrent pneumonia and sepsis, multiple abdominal reoperations for ischemic colitis and retroperitoneal abscess prolonged his recovery. He was discharged from the hospital after four months and is alive and well now 14 months after his operation. He is the first long-term survivor after IVOX therapy in Europe. IVOX may be successfully used in selected patients while the indications and it's potential role in the therapy of severe respiratory failure still need to be defined.

Bioavailability of pharmaceuticals in waters close to wastewater treatment plants: use of fish bile for exposure assessment

Pharmaceuticals are ubiquitous in surface waters as a consequence of discharges from municipal wastewater treatment plants. However, few studies have assessed the bioavailability of pharmaceuticals to fish in natural waters. In the present study, passive samplers and rainbow trout were experimentally deployed next to three municipal wastewater treatment plants in Finland to evaluate the degree of animal exposure. Pharmaceuticals from several therapeutic classes (in total 15) were analyzed by liquid chromatography-tandem mass spectrometry in extracts of passive samplers and in bile and blood plasma of rainbow trout held at polluted sites for 10 d. Each approach indicated the highest exposure near wastewater treatment plant A and the lowest near that of plant C. Diclofenac, naproxen, and ibuprofen were found in rainbow trout, and their concentrations in bile were 10 to 400 times higher than in plasma. The phase I metabolite hydroxydiclofenac was also detected in bile. Hence, bile proved to be an excellent sample matrix for the exposure assessment of fish. Most of the monitored pharmaceuticals were found in passive samplers, implying that they may overestimate the actual exposure of fish in receiving waters. Two biomarkers, hepatic vitellogenin and cytochrome P4501A, did not reveal clear effects on fish, although a small induction of vitellogenin mRNA was observed in trout caged near wastewater treatment plants B and C.

Evaluation of histological, serological and clinical changes in response to abatacept treatment of primary Sjögren's syndrome: A pilot study

Objectives To prospectively evaluate histopathologic, blood cellular, serological and clinical changes in response to abatacept treatment in patients with primary Sjögren's syndrome (pSS). Methods Blood, saliva and minor salivary gland biopsies were obtained before and after the last of 8 doses of abatacept in 11 pSS patients. The histologic data evaluated the number of lymphocytic foci and of B- and T-cell subtypes (CD20(+) , CD3(+) , CD4(+) , CD8(+) ). The numbers of FoxP3(+) regulatory T-cells were measured and the FoxP3 /CD 3 ratio was calculated. Histologic data were compared with results from peripheral blood and with changes in saliva secretion. Results The numbers of lymphocytic foci decreased significantly (p=0.041). Numbers of local FoxP3(+) T-cells decreased significantly in percentage of total lymphocytic infiltrates (p=0.037). In the peripheral blood B-cells increased (p=0.038). This was due to an expansion of the naïve B cell pool (p=0.034). When adjusting for disease duration, an increase was also noted for total lymphocytes (p=0.044) and for CD 4 cells (p=0.009). Gamma globulins decreased significantly (p=0.005), but IgG reduction did not reach significance. Adjusted for disease duration, saliva production increased significantly (p=0.029). Conclusions CTLA4-Ig treatment significantly reduces glandular inflammation in pSS, induces several celluar changes and increases saliva production. Remarkably, this increase in saliva production is significantly influenced by disease duration.

The Global Digital Divide as Impeded Access to Content

The paper seeks a re-conceptualization of the global digital divide debate. It critically explores the predominant notion, its evolution and measurement, as well as the policies that have been advanced to bridge the digital divide. Acknowledging the complexity of this inequality, the paper aims at analyzing the disparities beyond the connectivity and the skills barriers. Without understating the first two digital divides, it is argued that as the Internet becomes more sophisticated and more integrated into economic, social and cultural processes, a ‘third’ generation of divides becomes critical. These divides are drawn not at the entry to the net but within the net itself, and limit access to content. The increasing barriers to content, although of diverse nature, all relate to some governance characteristics inherent in cyberspace, such as global spillover of local decisions, regulation through code or proliferation of self- and co-regulatory models. It is maintained that as the practice of intervention intensifies in cyberspace, multiple and far-reaching points of control outside formal legal institutions are created, which threaten the availability of public goods and make the pursuit of public objectives difficult. This is an aspect that is rarely addressed in the global digital divide discussions, even in comprehensive analysis and political initiatives such as the World Summit on the Information Society. Yet, the conceptualization of the digital divide as impeded access to content may be key in terms of ensuring real participation and catering for the long-term implications of digital technologies.