An augmented Lanczos algorithm for the efficient computation of a dot-product of a function of a large sparse symmetric matrix

The Lanczos algorithm is appreciated in many situations due to its speed. and economy of storage. However, the advantage that the Lanczos basis vectors need not be kept is lost when the algorithm is used to compute the action of a matrix function on a vector. Either the basis vectors need to be kept, or the Lanczos process needs to be applied twice. In this study we describe an augmented Lanczos algorithm to compute a dot product relative to a function of a large sparse symmetric matrix, without keeping the basis vectors.

EMA analysis of tongue function in children with dysarthria following traumatic brain injury

Primary objective : To investigate the speed and accuracy of tongue movements exhibited by a sample of children with dysarthria following severe traumatic brain injury (TBI) during speech using electromagnetic articulography (EMA). Methods and procedures : Four children, aged between 12.75-17.17 years with dysarthria following TBI, were assessed using the AG-100 electromagnetic articulography system (Carstens Medizinelektronik). The movement trajectories of receiver coils affixed to each child's tongue were examined during consonant productions, together with a range of quantitative kinematic parameters. The children's results were individually compared against the mean values obtained by a group of eight control children (mean age of 14.67 years, SD 1.60). Main outcomes and results : All four TBI children were perceived to exhibit reduced rates of speech and increased word durations. Objective EMA analysis revealed that two of the TBI children exhibited significantly longer consonant durations compared to the control group, resulting from different underlying mechanisms relating to speed generation capabilities and distances travelled. The other two TBI children did not exhibit increased initial consonant movement durations, suggesting that the vowels and/or final consonants may have been contributing to the increased word durations. Conclusions and clinical implications : The finding of different underlying articulatory kinematic profiles has important implications for the treatment of speech rate disturbances in children with dysarthria following TBI.

Evaluation of lung function abnormalities prevalence in poultry workers

Introduction - Poultry workers can be at an increased risk of occupational respiratory diseases, like asthma, chronic obstructive pulmonary disease and extrinsic allergic alveolitis. Spirometry screening is fundamental to early diagnosis trough the identification of related ventilatory defects. Purpose - We aimed to assess the prevalence of lung function abnormalities in poultry workers.

De Novo Hypertension and Decline of Renal Function in a Young Woman with Systemic Lupus Erythematosus and Antiphospholipid Syndrome

Antiphospholipid syndrome nephropathy and lupus nephritis have similar clinical and laboratory manifestations and achieving the accuracy of diagnosis required for correct treatment frequently necessitates a kidney biopsy. We report the case of a 29-year-old woman referred to the nephrology service for de novo hypertension, decline of renal function and proteinuria. She had had systemic lupus erythematosus and antiphospholipid syndrome since the age of 21 and was taking oral anticoagulation. Two weeks later, after treatment of hypertension and achievement of adequate coagulation parameters, a percutaneous renal biopsy was performed. The biopsy revealed chronic lesions of focal cortical atrophy, arterial fibrous intimal hyperplasia and arterial thromboses, which are typical features of antiphospholipid syndrome nephropathy. We describe the clinical manifestations and histopathology of antiphospholipid syndrome nephropathy and review the literature on renal biopsy in patients receiving anticoagulation.

Minimum detection limit of an in-house nested-PCR assay for herpes simplex virus and varicella zoster virus

Introduction Herpes simplex virus (HSV) and varicella zoster virus (VZV) are responsible for a variety of human diseases, including central nervous system diseases. The use of polymerase chain reaction (PCR) techniques on cerebrospinal fluid samples has allowed the detection of viral DNA with high sensitivity and specificity. Methods Serial dilutions of quantified commercial controls of each virus were subjected to an in-house nested-PCR technique. Results The minimum detection limits for HSV and VZV were 5 and 10 copies/µL, respectively. Conclusions The detection limit of nested-PCR for HSV and VZV in this study was similar to the limits found in previous studies.

Regulación de la función de macrófagos por Cryptococcus neoformans y Cryptococcus gattii y su participación en la generación de la inmunidad adaptativa antifúngica. Regulation of macrophage function by Cryptococcus neoformans and Cryptococcus gattii and their role in the antifungal adaptative immunity.

La criptococosis es causada por la inhalación de levaduras encapsuladas de Cryptococcus neoformans o Cryptococcus gattii. Representa una de las tres infecciones graves por oportunistas en pacientes con SIDA y existe aproximadamente un 6 por ciento de incidencia de criptococosis clínica en pacientes con transplante de órganos sólidos. Estas dos especies difieren la fisiopatogenia durante la infección. El factor de virulencia principal de Cryptococcus sp. es la presencia del polisacárido capsular, glucuronoxilomanano (GXM), de alto peso molecular, que es continuamente secretado por las levaduras. Los macrófagos son células centrales en la respuesta innata al hongo, los cuales deben ser activados por linfocitos T helper 1 para un eficiente control de la infección. Sin embargo, estas células también son suceptibles al parasitismo intracelular, permitiendo la infección persistente y la diseminación a sitios extrapulmonares. Este proyecto propone investigar la capacidad de levaduras de C. neoformans, C. gattii y de los polisacáridos capsulares para modular la respuesta proinflamatoria de los macrófagos. Queremos estudiar si el tratamiento de macrófagos con levaduras o polisacárido puede inducir perfiles supresores de la respuesta protectiva T helper 1, tales como linfocitos T helper 2 o T reguladores, favoreciendo la sobrevida intracelular del hongo. Además, pensamos que C. neoformans o C. gattii podrían inducir un activación diferencial de macrófagos lo que condicionaría la respuesta adaptativa, lo que podría explicar las diferencias en la fisiopatogenia de estas dos especies. Procedimientos experimentales -Microorganismos y obtención de GXM: se trabajará con C. neoformans variedad grubii, cepa ATCC 62067 y C. gattii serotipo B, cepa NIH112B. Se obtendrán polisacáridos capsulares (GXM) de C. neoformans y C. gattii por precipitación con etanol y y acomplejamiento selectivo con CTAB. - Obtención de macrófagos murinos y cultivos celulares: se obtendrán macrófagos por lavados peritoneales y/o alveolares de ratones BALB/c. Los macrófagos se cultivarán por 24 h en ausencia o presencia de levaduras muertas o vivas (sin opsonizar u opsonizadas) de C. neoformans o C. gattii o en presencia de GXM purificado. -Objetivo 1. Estudio de la modulación de las propiedades proinflamatorias de Mac: en sobrenadantes de los cultivos se medirán las citoquinas por ELISA de captura y en lisados celulares, la expresión de las enzimas (iNOS, arginasa, IDO) por western blot. Se analizará por citometría de flujo la expresión de MCHII y moléculas CD80, CD86, CD40, CTLA-4. -Objetivo 2. Estudios in vitro de la capacidad de macrófagos tratados con levaduras o GXM para inducir linfocitos Th1, Th2 o Treg: los macrófagos preincubados con GXM o levaduras, se incubarán con linfocitos autólogos estimulados con anti-CD3. Se medirá la proliferación celular y el perfil de citoquinas por citomtría de flujo. Células T CD4+ CD25- serán purificadas de suspenciones esplénicas de ratones normales. Luego las células serán incubadas con macrófagos (sin tratar o tratados con levaduras o GXM) y estimulados con anti-CD3. Se analizará la proliferación celular con CFSE y expresión de CD4, CD25 y Foxp3 . - Objetivo 3. Estudios in vivo de la capacidad de levaduras o GXM para inducir linfocitos Th1, Th2 o Treg . Rol de los macrófagos in vivo: Los ratones serán inyectados con 100000 levaduras o con 200 µg de GXM puro vía endovenosa y luego de 7, 14, 30 y 40 días se evaluarán las poblaciones celulares de bazo, por citometría de flujo usando marcaciones simultáneas para CD4, CD8, CD25, Foxp3 y citoquinas intracelulares. Para investigar la participación in vivo de los macrófagos, se depletaran estas células inyectando los animales con PBS-liposomas o clodronato (DMDP)-liposomas por vía endovenosa o inhalatoria (200- 300 µl por ratón). Luego de 24 h, los animales se infectarán con levaduras o inocularán con GXM y se evaluarán los perfiles de células T esplénicos o de nódulos linfaticos.

Assessment of Autonomic Function by Phase Rectification of RRInterval Histogram Analysis in Chagas Disease

Background:In chronic Chagas disease (ChD), impairment of cardiac autonomic function bears prognostic implications. Phase‑rectification of RR-interval series isolates the sympathetic, acceleration phase (AC) and parasympathetic, deceleration phase (DC) influences on cardiac autonomic modulation.Objective:This study investigated heart rate variability (HRV) as a function of RR-interval to assess autonomic function in healthy and ChD subjects.Methods:Control (n = 20) and ChD (n = 20) groups were studied. All underwent 60-min head-up tilt table test under ECG recording. Histogram of RR-interval series was calculated, with 100 ms class, ranging from 600–1100 ms. In each class, mean RR-intervals (MNN) and root-mean-squared difference (RMSNN) of consecutive normal RR-intervals that suited a particular class were calculated. Average of all RMSNN values in each class was analyzed as function of MNN, in the whole series (RMSNNT), and in AC (RMSNNAC) and DC (RMSNNDC) phases. Slopes of linear regression lines were compared between groups using Student t-test. Correlation coefficients were tested before comparisons. RMSNN was log-transformed. (α < 0.05).Results:Correlation coefficient was significant in all regressions (p < 0.05). In the control group, RMSNNT, RMSNNAC, and RMSNNDCsignificantly increased linearly with MNN (p < 0.05). In ChD, only RMSNNAC showed significant increase as a function of MNN, whereas RMSNNT and RMSNNDC did not.Conclusion:HRV increases in proportion with the RR-interval in healthy subjects. This behavior is lost in ChD, particularly in the DC phase, indicating cardiac vagal incompetence.

Advancing the understanding of brain function with multivariate pattern analysis

Magdeburg, Univ., Fak. für Naturwiss., Diss., 2009

Perinatal care at the limit of viability between 22 and 26 completed weeks of gestation in Switzerland.

Perinatal care of pregnant women at high risk for preterm delivery and of preterm infants born at the limit of viability (22-26 completed weeks of gestation) requires a multidisciplinary approach by an experienced perinatal team. Limited precision in the determination of both gestational age and foetal weight, as well as biological variability may significantly affect the course of action chosen in individual cases. The decisions that must be taken with the pregnant women and on behalf of the preterm infant in this context are complex and have far-reaching consequences. When counselling pregnant women and their partners, neonatologists and obstetricians should provide them with comprehensive information in a sensitive and supportive way to build a basis of trust. The decisions are developed in a continuing dialogue between all parties involved (physicians, midwives, nursing staff and parents) with the principal aim to find solutions that are in the infant's and pregnant woman's best interest. Knowledge of current gestational age-specific mortality and morbidity rates and how they are modified by prenatally known prognostic factors (estimated foetal weight, sex, exposure or nonexposure to antenatal corticosteroids, single or multiple births) as well as the application of accepted ethical principles form the basis for responsible decision-making. Communication between all parties involved plays a central role. The members of the interdisciplinary working group suggest that the care of preterm infants with a gestational age between 22 0/7 and 23 6/7 weeks should generally be limited to palliative care. Obstetric interventions for foetal indications such as Caesarean section delivery are usually not indicated. In selected cases, for example, after 23 weeks of pregnancy have been completed and several of the above mentioned prenatally known prognostic factors are favourable or well informed parents insist on the initiation of life-sustaining therapies, active obstetric interventions for foetal indications and provisional intensive care of the neonate may be reasonable. In preterm infants with a gestational age between 24 0/7 and 24 6/7 weeks, it can be difficult to determine whether the burden of obstetric interventions and neonatal intensive care is justified given the limited chances of success of such a therapy. In such cases, the individual constellation of prenatally known factors which impact on prognosis can be helpful in the decision making process with the parents. In preterm infants with a gestational age between 25 0/7 and 25 6/7 weeks, foetal surveillance, obstetric interventions for foetal indications and neonatal intensive care measures are generally indicated. However, if several prenatally known prognostic factors are unfavourable and the parents agree, primary non-intervention and neonatal palliative care can be considered. All pregnant women with threatening preterm delivery or premature rupture of membranes at the limit of viability must be transferred to a perinatal centre with a level III neonatal intensive care unit no later than 23 0/7 weeks of gestation, unless emergency delivery is indicated. An experienced neonatology team should be involved in all deliveries that take place after 23 0/7 weeks of gestation to help to decide together with the parents if the initiation of intensive care measures appears to be appropriate or if preference should be given to palliative care (i.e., primary non-intervention). In doubtful situations, it can be reasonable to initiate intensive care and to admit the preterm infant to a neonatal intensive care unit (i.e., provisional intensive care). The infant's clinical evolution and additional discussions with the parents will help to clarify whether the life-sustaining therapies should be continued or withdrawn. Life support is continued as long as there is reasonable hope for survival and the infant's burden of intensive care is acceptable. If, on the other hand, the health care team and the parents have to recognise that in the light of a very poor prognosis the burden of the currently used therapies has become disproportionate, intensive care measures are no longer justified and other aspects of care (e.g., relief of pain and suffering) are the new priorities (i.e., redirection of care). If a decision is made to withhold or withdraw life-sustaining therapies, the health care team should focus on comfort care for the dying infant and support for the parents.

Rigorous derivation of a nonlinear diffusion equation as fast-reaction limit of a continuous coagulation-fragmentation model with diffusion

Weak solutions of the spatially inhomogeneous (diffusive) Aizenmann-Bak model of coagulation-breakup within a bounded domain with homogeneous Neumann boundary conditions are shown to converge, in the fast reaction limit, towards local equilibria determined by their mass. Moreover, this mass is the solution of a nonlinear diffusion equation whose nonlinearity depends on the (size-dependent) diffusion coefficient. Initial data are assumed to have integrable zero order moment and square integrable first order moment in size, and finite entropy. In contrast to our previous result [CDF2], we are able to show the convergence without assuming uniform bounds from above and below on the number density of clusters.

Alterations of Neuromuscular Function after the World's Most Challenging Mountain Ultra-Marathon.

We investigated the physiological consequences of the most challenging mountain ultra-marathon (MUM) in the world: a 330-km trail run with 24000 m of positive and negative elevation change. Neuromuscular fatigue (NMF) was assessed before (Pre-), during (Mid-) and after (Post-) the MUM in experienced ultra-marathon runners (n = 15; finish time  = 122.43 hours ±17.21 hours) and in Pre- and Post- in a control group with a similar level of sleep deprivation (n = 8). Blood markers of muscle inflammation and damage were analyzed at Pre- and Post-. Mean ± SD maximal voluntary contraction force declined significantly at Mid- (-13±17% and -10±16%, P<0.05 for knee extensor, KE, and plantar flexor muscles, PF, respectively), and further decreased at Post- (-24±13% and -26±19%, P<0.01) with alteration of the central activation ratio (-24±24% and -28±34% between Pre- and Post-, P<0.05) in runners whereas these parameters did not change in the control group. Peripheral NMF markers such as 100 Hz doublet (KE: -18±18% and PF: -20±15%, P<0.01) and peak twitch (KE: -33±12%, P<0.001 and PF: -19±14%, P<0.01) were also altered in runners but not in controls. Post-MUM blood concentrations of creatine kinase (3719±3045 Ul·(1)), lactate dehydrogenase (1145±511 UI·L(-1)), C-Reactive Protein (13.1±7.5 mg·L(-1)) and myoglobin (449.3±338.2 µg·L(-1)) were higher (P<0.001) than at Pre- in runners but not in controls. Our findings revealed less neuromuscular fatigue, muscle damage and inflammation than in shorter MUMs. In conclusion, paradoxically, such extreme exercise seems to induce a relative muscle preservation process due likely to a protective anticipatory pacing strategy during the first half of MUM and sleep deprivation in the second half.