Zika virus infection and Guillain-Barré syndrome in three patients from Suriname

We present three patients from Suriname who were diagnosed with Guillain-Barré syndrome (GBS) during the Zika virus (ZIKV) outbreak in this country. One patient had a positive ZIKV urine real-time RT-PCR (qRT-PCR) result. The other two patients had a negative ZIKV urine qRT-PCR but a positive virus neutralization test and presence of IgG antibodies against ZIKV in the serum. Considering the evidence of a past ZIKV infection and absence of evidence for recent infections with the most common preceding infections of GBS, it is very likely that these GBS cases were triggered by ZIKV

Attitudeverschillen ten aanzien van taalvereenvoudiging

Contains fulltext : 20401_attiteaav.pdf (publisher's version ) (Open Access

Određivanje krivulje magnetiziranja vektorski upravljanog asinkronog motora kod malih opterećenja

In many drives the induction motor torque is transferred to the load through complex mechanical connections which produce an initial load. In such cases, to identify the magnetization curve by the no-load test it is necessary to decouple the motor from the transfer gear what is expensively and time-consuming. In an attempt to avoid the motor mechanical decoupling in the case of hoist crane systems, in this paper a method is proposed for the magnetization curve identification of the indirect rotor flux oriented (IRFO) induction machine at low-load conditions. Two flux controllers with estimated feedback quantities are added to the basic structure of the IRFO control drive. One of these controllers is used to control desired operating point on the magnetization curve and the other for on-line adaption of the reference frame position. The proposed algorithm is implemented in a commercial drive as a part of the self-commissioning module. Afterward, the magnetization curve of the 22 kW induction motor was identified and compared with the one obtained by the no-load test. The method sensitivity to the load torque and the transient inductance has also been considered.Brojni su primjeri pogona u kojima se moment asinkronog stroja prenosi na radni mehanizam preko mehaničkih reduktora koji mogu predstavljati značajno opterećenje motoru i u režimu neopterećenog pogona. Da bi se u takvim slučajevima odredila krivulja magnetiziranja iz pokusa praznog hoda nužno je odspojiti motor od reduktora što je skupo i vremenski zahtjevno. U pokušaju da se izbjegne mehaničko odspajanje motora kod dizaličnih sustava, u ovom je radu predložena metoda za određivanje krivulje magnetizranja vektorski upravljanog asinkronog motora kod malih iznosa opterećenja. Dva regulatora ulančenog toka s estimiranim veličinama u granama povratne veze dodani su osnovnoj strukturi vektorski upravljanog pogona. Jedan od regulatora koristi se za upravljanje željenom radnom točkom na krivulji magnetiziranja dok se drugi koristi za podešavanje referentnog položaja vektora toka rotora. Predloženi algoritam implementiran je u komercijalnom uređaju kao jedan od samopodešavajućih modula koji se koriste prilikom puštanja u rad pogona. Nakon toga je opisanim postupkom određena krivulja magnetiziranja 22 kW asinkronog motora i uspoređena s krivuljom dobivenom iz klasičnog pokusa praznog hoda. Također je razmotrena i osjetljivost metode na iznos momenta opterećenja i tranzijentnog induktiviteta

Identification and characterisation of citrullinated antigen-specific B cells in peripheral blood of patients with rheumatoid arthritis

Pathophysiology and treatment of rheumatic disease

Persistently activated, proliferative memory autoreactive B cells promote inflammation in rheumatoid arthritis

Autoreactive B cells mediate autoimmune pathology, but exactly how remains unknown. A hallmark of rheumatoid arthritis (RA), a common autoimmune disease, is the presence of disease-specific anticitrullinated protein antibodies (ACPAs). Here, we showed that ACPA-positive B cells in patients with RA strongly expressed T cell-stimulating ligands, produced abundant proinflammatory cytokines, and were proliferative while escaping inhibitory signals. This activated state was found at different degrees in different stages of disease: highest in patients with recentonset RA, moderate in patients with established RA, and far less pronounced in ACPA-positive individuals "at risk" for developing disease. The activated autoreactive B cell response persisted in patients who achieved clinical remission with conventional treatment. ACPA-positive B cells in blood and synovial fluid secreted increased amounts of the chemoattractant interleukin-8, which attracted neutrophils, the most abundant immune cell in arthritic joints. Tetanus toxoid-specific B cells from the same patients exhibited properties of memory B cells without the activation and proliferation phenotype, but these cells transiently acquired a similar proliferative phenotype upon booster vaccination. Together, these data indicated that continuous antigenic triggering of autoreactive B cells occurs in human autoimmune disease and support the emerging concept of immunological activity that persists under treatment even in clinical remission, which may revise our current concept of treatment targets for future therapeutic interventions. In addition, our data pointed to a pathogenic role of ACPA-positive B cells in the inflammatory disease process underlying RA and favor approaches that aim at their antigen-specific inactivation or depletion.Pathophysiology and treatment of rheumatic disease

Multicenter assessment of CSF-phosphorylated tau for the prediction of conversion of MCI

BACKGROUND: The measurement of hyperphosphorylated tau (p-tau) in CSF has been proposed as a biomarker candidate for the prediction of Alzheimer disease (AD) in patients with mild cognitive impairment (MCI). However, a standard quantitative criterion of p-tau has not been evaluated. OBJECTIVE: To assess in a multicenter study the predictive accuracy of an a priori defined criterion of tau phosphorylated at threonine 231 (p-tau231) for the prediction of conversion from MCI to AD during a short-term observation interval. METHODS: The study included 43 MCI converters, 45 stable MCI (average follow-up interval = 1.5 years), and 57 healthy controls (at baseline only). Subjects were recruited at four international expert sites in a retrospective study design. Cox regression models stratified according to center were used to predict conversion status. Bootstrapped 95% CIs of classification accuracy were computed. RESULTS: Levels of p-tau231 were a significant predictor of conversion (B = 0.026, p = 0.001), independent of age, gender, Mini-Mental State Examination, and ApoE genotype. For an a priori-defined cutoff point (27.32 pg/mL), sensitivity ranged between 66.7 and 100% and specificity between 66.7 and 77.8% among centers. The bootstrapped mean percentage of correctly classified cases was 79.95% (95% CI = 79.9 to 80.00%). Post hoc defined cutoff values yielded a mean bootstrapped classification accuracy of 80.45% (95% CI = 80.24 to 80.76%). CONCLUSIONS: An a priori defined cutoff value of p-tau231 yields relatively stable results across centers, suggesting a good feasibility of a standard criterion of p-tau231 for the prediction of Alzheimer disease