Einfluß der Substrate Sauerstoff (O2) und L-Arginin der Stickstoffmonoxid(NO)-Synthase auf die endogene NO-Bildung und die Atemluftkonzentration von NO

Zielsetzungen: Beeinflussung der endogenen NO-Bildung durch die Substrate der NOS und durch NO selbst. Entwicklung von NO-Atemkurven und von Meßmethoden für die eNO-Bestimmung in der Atemluft, um die Etablierung der NO-Messung in Diagnostik und Therapieüberwachung weiterzuentwickeln. Weiterentwicklung der NO-Meßtechnik, so daß Atemluftkurven online abgeleitet werden können und damit eine bessere örtliche Zuordnung ermöglicht wird. Probanden: An Gruppe 1 wurden Untersuchungen zum Meßgasvolumenstrom durchgeführt. An Gruppe 2 machten wir Nasenmessungen. Vergleichsmessungen zwischen eNO-Reservoir und eNO-Atemluftkurve wurden an Gruppe 3 durchgeführt. Mit Gruppe 4 wurden Messungen zur Stabilität von eNO durchgeführt. Der Einfluß der Umgebungsluft auf eNO wurden an Gruppe 5 untersucht. In Gruppe 6 wurde der Effekt von Sauerstoff untersucht, ebenso in Gruppe 7. Die Argininbelastungsmessungen erfolgten an Gruppe 8. An den Gruppen 9 und 10 erfolgten Untersuchungen an intubierten Probanden. Ergebnisse: Die Untersuchung zum Meßgasvolumenstrom an Gruppe 1 zeigten Werteabweichungen zwischen 9±4 ppb und 11±4 ppb bei Meßgasvolumenströmen zwischen 1000 ml/min und 500 ml/min. Die Nasenmessungen an Gruppe 2 zeigten Nasen-NO-Mittelwerte von 147±92 ppb. An Gruppe 3 wurden die Vergleichsmessungen von eNO-Reservoir und eNO-Atemluftkurve durchgeführt. Die MW der Atemluftkurve lagen um 4 ppb höher als die MW der Reservoirmessungen. Bei einer Korrelation von r2=0,83 zeigten die Werte nach Bland-Altman keine Übereinstimmung. Die Messungen zur Stabilität von eNO wurden an Gruppe 4 durchgeführt. An fünf aufeinanderfolgenden Tagen zeigten die Mittelwerte der Probanden VK zwischen 0,13-0,57 bei 21% FiO2, bei 50% FiO2 lagen die VK zwischen 0,14-0,65. Es fanden sich große Schwankungen bei diesen Werten. Bei den fünf aufeinanderfolgenden Messungen an einem Tag zeigten die Probanden bei 21% FiO2 VK von 0-0,13. Bei 50% FiO2 lagen die VK zwischen 0,05-0,2. Die Abweichungen dieser Werte waren sehr gering, eNO war relativ stabil. An Gruppe 5 wurden die Messungen zum Einfluß der Umgebungsluft auf eNO durchgeführt. Bei den Messungen mit Umgebungs-NO > 0 lag der MW mit 13±4 ppb höher, als bei den Messungen mit Umgebungs-NO = 0 (MW = 9±5 ppb). Die Werteabweichungen der Probanden erfolgten in alle Richtungen. An Gruppe 6 wurden Messungen zum Einfluß von O2 mit fünf unterschiedlichen FiO2-Konzentrationen durchgeführt. Es ergab sich ein Anstieg von 3±2 ppb bei 10% FiO2 auf 7±2 ppb bei 21% FiO2. Bei einer Erhöhung auf 50% FiO2 stieg eNO auf 12±5 ppb an. Die NOS scheint durch O2 stimulierbar zu sein, eNO steigt signifikant an, oberhalb von 50 % FiO2 kommt es zur Sättigung. Bei Hypoxie fällt eNO ab. An Gruppe 7 wurden Messungen zum Einfluß von O2 mit zwei FiO2-Werten durchgeführt. Hier wurde ein Werteanstieg von 5±4 ppb bei 21% FiO2 auf 8±5 ppb bei 50% FiO2 gemessen. Bei einem Breathholding-Manöver konnte ebenfalls ein eNO-Anstieg erreicht werden. Die Argininbelastungsmessungen erfolgten mit Gruppe 8. Es kam zu einem eNO-Anstieg von 3±2 ppb vor Arginingabe auf 10±5 ppb 30 Minuten nach Arginininfusion. Es folgte ein Werteplateau mit einem leichten Abfall von eNO auf 9±5 ppb nach 120 Minuten. An den Gruppen 9 und 10 wurden eNO-Messungen an intubierten Probanden durchgeführt. Mit eNO-MW zwischen 1±1 ppb und 3±1 ppb lagen sie niedriger als die Werte bei nichtintubierten Probanden. Schlußfolgerungen: Es wurde gezeigt, daß NO in der Atemluft meßbar ist und daß die Werte eines Atemzyklus als Kurve aufgezeigt werden können. Messungen mit einem empfindlicheren Meßgerät könnten die Kurven und ihre Aussagekraft weiter verbessern. Die Untersuchungen haben bestätigt, daß die Bildung und Freisetzung von NO stimulierbar ist. Dadurch scheint es möglich, Aussagen über die Anwesenheit von NOS zu machen. Die eNO-Messung könnte eine neue Möglichkeit in der Diagnostik und Therapieüberwachung von Krankheiten bieten, die mit veränderter NOS-Aktivität einhergehen. Der NO-Analysator konnte verbessert werden. Für die Fortführung der Untersuchungen sollte ein Gerät mit einer höheren Empfindlichkeit verwendet werden, um niedrige eNO-Werte besser erfassen zu können

Protocol for a multicentre, parallelgroup, open-label randomised controlled trial comparing ferric carboxymaltose with the standard of care in anaemic Malawian pregnant women: the REVAMP trial

Introduction Anaemia in pregnancy remains a critical global health problem, affecting 46% of pregnant women in Africa and 49% in Asia. Oral iron therapy requires extended adherence to achieve correction of anaemia and replenishment of iron stores. Ferric carboxymaltose (FCM) is a recently established intravenous iron formulation associated with substantial advantages in safety, speed of delivery and total dose deliverable in a single infusion. We aim to determine whether FCM given once during the second trimester of pregnancy compared with standard oral iron distributed through routine antenatal services is effective and safe for treatment of moderate to severe maternal anaemia in sub-Saharan Africa. Methods and analysis The randomized controlled trial of the effect of intravenous iron on anaemia in Malawian pregnant women (REVAMP) is a two-arm confirmatory individually randomised trial set in Blantyre and Zomba districts in Malawi. The trial will randomise 862 women in the second trimester of pregnancy with a capillary haemoglobin concentration below 100.0 g/L. The study comprises two arms: (a) intravenous FCM (20 mg/kg up to 1000 mg) given once at randomisation, and (b) standard of care oral iron (65 mg elemental iron two times per day) for 90 days (or the duration of pregnancy, whichever is shorter) provided according to local healthcare practices. Both arms receive sulfadoxine-pyrimethamine as intermittent preventive treatment in pregnancy. The primary outcome is the prevalence of anaemia (Hb <110.0 g/L) at 36 weeks’ gestation. Secondary outcomes include birth weight, gestation duration and safety outcomes, including clinical malaria, serious perinatal events and postpartum haematologic and health-related outcomes in the mother and child. Ethics and dissemination Ethical approval was granted by the Research Ethics Committee (COMREC P.02/18/2357) in Malawi and the Human Research Ethics Committee (WEHI: 18/02), Melbourne, Australia. The protocol is registered with the Australian and New Zealand Clinical Trials Registry. The results will be shared with the local community that enabled the research, and also to the international fora.publishedVersio

Caspase-8 mediates inflammation and disease in rodent malaria

Earlier studies indicate that either the canonical or non-canonical pathways of inflammasome activation have a limited role on malaria pathogenesis. Here, we report that caspase-8 is a central mediator of systemic inflammation, septic shock in the Plasmodium chabaudi-infected mice and the P. berghei-induced experimental cerebral malaria (ECM). Importantly, our results indicate that the combined deficiencies of caspases-8/1/11 or caspase-8/gasdermin-D (GSDM-D) renders mice impaired to produce both TNFalpha and IL-1beta and highly resistant to lethality in these models, disclosing a complementary, but independent role of caspase-8 and caspases-1/11/GSDM-D in the pathogenesis of malaria. Further, we find that monocytes from malaria patients express active caspases-1, -4 and -8 suggesting that these inflammatory caspases may also play a role in the pathogenesis of human disease

Induction of Strain-Transcending Antibodies Against Group A PfEMP1 Surface Antigens from Virulent Malaria Parasites

Sequence diversity in pathogen antigens is an obstacle to the development of interventions against many infectious diseases. In malaria caused by Plasmodium falciparum, the PfEMP1 family of variant surface antigens encoded by var genes are adhesion molecules that play a pivotal role in malaria pathogenesis and clinical disease. PfEMP1 is a major target of protective immunity, however, development of drugs or vaccines based on PfEMP1 is problematic due to extensive sequence diversity within the PfEMP1 family. Here we identified the PfEMP1 variants transcribed by P. falciparum strains selected for a virulence-associated adhesion phenotype (IgM-positive rosetting). The parasites transcribed a subset of Group A PfEMP1 variants characterised by an unusual PfEMP1 architecture and a distinct N-terminal domain (either DBLα1.5 or DBLα1.8 type). Antibodies raised in rabbits against the N-terminal domains showed functional activity (surface reactivity with live infected erythrocytes (IEs), rosette inhibition and induction of phagocytosis of IEs) down to low concentrations (<10 µg/ml of total IgG) against homologous parasites. Furthermore, the antibodies showed broad cross-reactivity against heterologous parasite strains with the same rosetting phenotype, including clinical isolates from four sub-Saharan African countries that showed surface reactivity with either DBLα1.5 antibodies (variant HB3var6) or DBLα1.8 antibodies (variant TM284var1). These data show that parasites with a virulence-associated adhesion phenotype share IE surface epitopes that can be targeted by strain-transcending antibodies to PfEMP1. The existence of shared surface epitopes amongst functionally similar disease-associated P. falciparum parasite isolates suggests that development of therapeutic interventions to prevent severe malaria is a realistic goal

Splenic differentiation and emergence of CCR5+CXCL9+CXCL10+ monocyte-derived dendritic cells in the brain during cerebral malaria

Dendritic cells have an important role in immune surveillance. After being exposed to microbial components, they migrate to secondary lymphoid organs and activate T lymphocytes. Here we show that during mouse malaria, splenic inflammatory monocytes differentiate into monocyte-derived dendritic cells (MO-DCs), which are CD11b+F4/80+CD11c+MHCIIhighDC-SIGNhighLy6c+ and express high levels of CCR5, CXCL9 and CXCL10 (CCR5+CXCL9/10+ MO-DCs). We propose that malaria-induced splenic MO-DCs take a reverse migratory route. After differentiation in the spleen, CCR5+CXCL9/10+ MO-DCs traffic to the brain in a CCR2-independent, CCR5-dependent manner, where they amplify the influx of CD8+ T lymphocytes, leading to a lethal neuropathological syndrome

Hipsometric equations for Pinus sp. at the Itatinga forest sciences experimental station, São Paulo

Dentre as essências florestais cultivadas no Brasil destacam-se as espécies do gênero Pinus, apresentando uma grande concentração na região Sul do país, sendo as espécies mais cultivadas o Pinus elliottii e Pinus taeda. O objetivo deste trabalho foi ajustar equações matemáticas para estimar a altura das árvores em povoamentos de Pinus taeda L, Pinus oocarpa e Pinus híbrido (Pinus oocarpa x Pinus caribaea var. hondurensis), na Estação Experimental de Ciências Florestais de Itatinga – São Paulo. Para isso foi realizado um inventário florestal estratificado e sistemático por idade (21, 22 e 24 anos), utilizando-se amostragem sistemática de 3 parcelas por área. Cada parcela consistiu de 90 árvores das quais foram medidos todos diâmetros à 1,30 m do solo (DAP) e medidas as alturas totais das 10 primeiras árvores de cada parcela mais as 5 dominantes de forma a abranger todas as classes do povoamento. Para o ajuste foram testadas 10 equações&nbsp; hipsómétricas,&nbsp; sendo&nbsp; selecionadas de acordo com os valores de coeficiente de determinação ajustado (R2aj), erro padrão residual (Syx%), coeficiente de variação (CV%), F e análise gráfica de resíduos. A melhor equação ajustada para descrever a relação h/d para as espécies Pinus taeda, Pinus oocarpa e híbrido Pinus (Pinus oocarpa x Pinus caribaea var. Hondurensis) em todas as idades foi a de Prodan.Among the forest essences cultivated in Brazil, the species of the genus Pinus stand out, presenting a great concentration in the South region of the country, with the most cultivated species being Pinus elliottii and Pinus taeda. The objective of this work was to adjust mathematical equations to estimate the height of trees in stands of Pinus taeda L, Pinus oocarpa and hybrid Pinus (Pinus oocarpa x Pinus caribaea var. Hondurensis), at the Experimental Forest Science Station in Itatinga - São Paulo. For this, a stratified and systematic forest inventory by age (21, 22 and 24 years) was carried out, using systematic sampling of 3 plots per area. Each plot consisted of 90 trees from which all diameters were measured at 1.30 m from the ground (DBH) and the total heights of the first 15 trees of each plot were measured in order to cover all classes of the stand. For the adjustment, 10 hypsometric equations were tested, being selected according to the values ​​of adjusted determination coefficient (R2aj), residual standard error (Syx%), variation coefficient (CV%), F and residual graphical analysis. The best equation adjusted to describe the h / d ratio for the species Pinus taeda, Pinus oocarpa and hybrid Pinus (Pinus oocarpa x Pinus caribaea var. Hondurensis) at all ages was that of Prodan

Antibodies That Induce Phagocytosis of Malaria Infected Erythrocytes: Effect of HIV Infection and Correlation with Clinical Outcomes

HIV infection increases the burden of disease of malaria in pregnancy, in part by impairing the development of immunity. We measured total IgG and phagocytic antibodies against variant surface antigens of placental-type CS2 parasites in 187 secundigravidae (65% HIV infected). In women with placental malaria infection, phagocytic antibodies to CS2VSA were decreased in the presence of HIV (p = 0.011) and correlated positively with infant birth weight (coef = 3.57, p = 0.025), whereas total IgG to CS2VSA did not. Phagocytic antibodies to CS2VSA are valuable tools to study acquired immunity to malaria in the context of HIV co-infection. Secundigravidae may be an informative group for identification of correlates of immunity

Immunisation with Recombinant PfEMP1 Domains Elicits Functional Rosette-Inhibiting and Phagocytosis-Inducing Antibodies to Plasmodium falciparum

BACKGROUND: Rosetting is a Plasmodium falciparum virulence factor implicated in the pathogenesis of life-threatening malaria. Rosetting occurs when parasite-derived P. falciparum Erythrocyte Membrane Protein One (PfEMP1) on the surface of infected erythrocytes binds to human receptors on uninfected erythrocytes. PfEMP1 is a possible target for a vaccine to induce antibodies to inhibit rosetting and prevent severe malaria. METHODOLOGY/FINDINGS: We examined the vaccine potential of the six extracellular domains of a rosette-mediating PfEMP1 variant (ITvar9/R29var1 from the R29 parasite strain) by immunizing rabbits with recombinant proteins expressed in E. coli. Antibodies raised to each domain were tested for surface fluorescence with live infected erythrocytes, rosette inhibition and phagocytosis-induction. Antibodies to all PfEMP1 domains recognized the surface of live infected erythrocytes down to low concentrations (0.02-1.56 µg/ml of total IgG). Antibodies to all PfEMP1 domains except for the second Duffy-Binding-Like region inhibited rosetting (50% inhibitory concentration 0.04-4 µg/ml) and were able to opsonize and induce phagocytosis of infected erythrocytes at low concentrations (1.56-6.25 µg/ml). Antibodies to the N-terminal region (NTS-DBL1α) were the most effective in all assays. All antibodies were specific for the R29 parasite strain, and showed no functional activity against five other rosetting strains. CONCLUSIONS/SIGNIFICANCE: These results are encouraging for vaccine development as they show that potent antibodies can be generated to recombinant PfEMP1 domains that will inhibit rosetting and induce phagocytosis of infected erythrocytes. However, further work is needed on rosetting mechanisms and cross-reactivity in field isolates to define a set of PfEMP1 variants that could induce functional antibodies against a broad range of P. falciparum rosetting parasites

Correlação dos níveis de NT-proBNP com CK-MB, troponina I, escore de risco timi e fração de ejeção do ventrículo esquerdo na síndrome coronariana aguda sem supradesnível do segmento ST

Exportado OPUSMade available in DSpace on 2019-08-12T06:56:25Z (GMT). No. of bitstreams: 1 luiz_ricardo_de_ata_de_castro.pdf: 418646 bytes, checksum: e6936db7ea67bf400203b5233095b273 (MD5) Previous issue date: 10A síndrome coronariana aguda sem elevação do segmento ST écaracterizada por pacientes com angina instável ou infarto agudo do miocárdio sem elevação do segmento ST, e, quando associada à elevação dos níveis do peptídeo natriurético cerebral, pode levar a taxas de mortalidade aumentadas em seguimento prolongado e ao maior risco de insuficiência cardíaca. O peptídeo natriurético cerebral humano é produzido no coração, principalmente nos ventrículos, estimulado pela distensão do miócito. Tal processamento libera uma molécula biologicamente ativa de 32 aminoácidos (peptídeo natriurético cerebral)e o fragmento N-terminal do peptídeo natriurético cerebral de 76 aminoácidos. Os objetivos da presente pesquisa foram avaliar o significado da dosagem plasmática do precursor do peptídeo natriurético cerebral em pacientes durante o período de internação hospitalar com síndrome coronariana aguda sem elevação dosegmento ST, angina instável e infarto agudo do miocárdio sem elevação do segmento ST, e correlacionar com os marcadores de necrose miocárdica (creatinofosfoquinase fração músculo-cerebral e troponina I), com o escore de risco TIMI e com a fração de ejeção do ventrículo esquerdo. O estudo foi observacional, transversal e descritivo, cuja amostra constituiu-se de 87 pacientes consecutivos com diagnóstico definitivo de síndrome coronariana aguda sem elevação do segmento ST. Os critérios de exclusão foram: diagnóstico prévio ousinais e sintomas de insuficiência cardíaca congestiva, níveis de creatinina > 2,5 mg/dl, infarto agudo do miocárdio recente e hipertensão arterial sistêmica grave. Amostras para dosagem do fragmento N-terminal do peptídeo natriurético cerebral foram colhidas em um intervalo de 72 horas a partir do início dos sintomas. O exame de ecocardiograma foi realizado para análise da fração de ejeção do ventrículo esquerdo. Os pacientes foram divididos em dois grupos: 37(42,5%) com angina instável e 50 (57,5%) com infarto agudo do miocárdio sem elevação do segmento ST. A fração de ejeção do ventrículo esquerdo superior a 40% foi encontrada em 86,2% do total de pacientes. Observou-se aumento dos níveis séricos do fragmento N-terminal do peptídeo natriurético cerebral mais significativo nos pacientes com infarto agudo do miocárdio sem elevação do segmento ST do que naqueles com angina instável (p 2.5 mg/dl; recent acute myocardial infarction and severe systemic arterial hypertension. The samples for the dosage of the N-terminal pro-brain natriuretic peptide were collected 72 hours after the beginning of the symptoms. The echocardiogram test was carried out in order to assess the left ventricular ejection fraction. The patients were divided into two groups: 37 (42.5%) with unstable angina; and 50 (57.5%) with non-ST elevation myocardial infarction. Left ventricular ejection fraction over 40% was found in 86.2% out of the total number of patients. Increased serum levels of the N-terminal pro-brain natriuretic peptideshowed to be more significant than those in patients with non-ST elevation myocardial infarction with unstable angina (p<0.001). Increased levels of Nterminal pro brain natriuretic peptide were associated with the increase in troponin I (rs=0.425, p<0.001), with the peak of creatine phosphokinase muscle-brain fraction (rs=0.458, p<0.001) and with the depression of the left ventricular ejection fraction (rs= 0.345, p=0.002), but was not correlated with the TIMI risk score (rs=0.082, p=0.44). Through multivariate analysis, the left ventricular ejection fraction (p=0.017), as well as the levels of troponin I (p=0.002) showed to beindependently correlated with the levels of the N-terminal pro-brain natriuretic peptide