976 resultados para Type I error probability


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AbstractObjective:To evaluate by magnetic resonance imaging changes in bone marrow of patients undergoing treatment for type I Gaucher’s disease.Materials and Methods:Descriptive, cross-sectional study of Gaucher’s disease patients submitted to 3 T magnetic resonance imaging of femurs and lumbar spine. The images were blindly reviewed and the findings were classified according to the semiquantitative bone marrow burden (BMB) scoring system.Results:All of the seven evaluated patients (three men and four women) presented signs of bone marrow infiltration. Osteonecrosis of the femoral head was found in three patients, Erlenmeyer flask deformity in five, and no patient had vertebral body collapse. The mean BMB score was 11, ranging from 9 to 14.Conclusion:Magnetic resonance imaging is currently the method of choice for assessing bone involvement in Gaucher’s disease in adults due to its high sensitivity to detect both focal and diffuse bone marrow changes, and the BMB score is a simplified method for semiquantitative analysis, without depending on advanced sequences or sophisticated hardware, allowing for the classification of the disease extent and assisting in the treatment monitoring.

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Les mécanismes qui régulent le processus de guérison de la peau lésée ne sont pas entièrement compris. Nous avons précédemment montré que les cellules dendritiques plasmocytoïdes (pDCs) sont normalement absentes de la peau saine mais infiltrent rapidement la peau humaine ainsi que celle des souris après une blessure cutanée. Après avoir infiltré la peau, ces pDCs sont capables de détecter les acides nucléiques par l'expression des récepteurs de type Toll 7 et 9 ce qui les active à produire de 1' interféron (IFN) de type I. Ce processus est primordial pour la re- épithélisation des blessures cutanées. Cependant, les mécanismes conduisant à l'infiltration et à 1'activation des pDCs restent inconnus. Dans notre projet, nous montrons que la chimiokine CxcllO est responsable de l'infiltration des pDCs. De façon importante, nous démontrons que les neutrophiles qui infiltrent également la peau lésée sont la source majeure de cette chimiokine. La déplétion des neutrophiles abolit d'ailleurs le recrutement des pDCs confirmant ainsi que CxcllO produit par les neutrophiles est responsable de l'infiltration des pDCs dans la peau endommagée. De façon intéressante, nous avons trouvé que CxcllO en plus de son activité chimiotactique, est capable de former des complexes avec l'ADN et d'activer ainsi les pDCs à produire de l'IFN de type I. De plus, nous avons observé que les neutrophiles qui infiltrent la peau forment des Neutrophil Extracellular Traps (NETs). Ces NETs sont constitués de filaments extracellulaires d'ADN recouverts par de nombreuses protéines principalement d'origine granulaire. D'une manière frappante, le blocage de la NETose ou l'utilisation de souris déficientes pour la formation de NETs altère le recrutement et l'activation des pDCs ainsi que la réponse inflammatoire qui en découle ainsi que le processus de re-epithélisation qui s'ensuit. En prenant en compte toutes ces données, nos résultats démontrent que suite à une blessure de la peau, les neutrophiles par la production de CxcllO contrôlent l'infiltration des pDCs dans la peau lésée et par la formation de NETs, promeuvent l'activation des pDCs. Notre étude fournit donc de nouvelles informations sur les mécanismes de guérison de la peau et ouvre de nouvelles perspectives thérapeutiques quant à la réparation tissulaire de la peau soit dans le but de l'amplifier ou de l'inhiber. -- The mechanisms that regulate healing of the injured skin are not well understood. We have previously shown that plasmacytoid dendritic cells (pDCs) are normally absent from the healthy skin, but rapidly infiltrate both murine and human skin upon injury. Upon skin infiltration, pDCs sense nucleic acids via TLR7/TLR9 and are activated to produce type I interferon (IFN), a process that is crucial for re-epithelialisation of skin wounds. However, the mechanisms that drive pDCs recruitment and activation in injured skin remain unclear. We show that CxcllO is responsible for pDCs infiltration. Importantly, we demonstrate that skin infiltrating neutrophils are the major source of this chemokine. Neutrophils depletion completely abrogated pDCs recruitment confirming that CxcllO- driven pDCs recruitment is controlled by neutrophils. Interestingly, CxcllO was also found to form complexes with DNA and to activate pDCs to produce Type I IFN in addition to its chemotactic activity. Moreover, we observed that infiltrating neutrophils release Neutrophils Extracellular Traps (NETs) composed of DNA filaments decorated with neutrophils-derived proteins. Strikingly, blocking NETosis or using mice deficient for NETs production impaired pDCs recruitment and activation as well as the subsequent inflammatory response and the re-epithelialisation process. Altogether, these data demonstrate that upon skin injury, neutrophils control pDCs infiltration into the injured skin by the release of CxcllO and via the production of NETs, they allow complex formation between CxcllO and NET-DNA leading to pDCs activation. Our findings provide new insights into the mechanisms of wound healing and open new avenues for potential therapeutic interventions to boost or inhibit wound repair in the skin.

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The skeleton undergoes continuous turnover throughout life. In women, an increase in bone turnover is pronounced during childhood and puberty and after menopause. Bone turnover can be monitored by measuring biochemical markers of bone resorption and bone formation. Tartrate-resistant acid phosphatase (TRACP) is an enzyme secreted by osteoclasts, macrophages and dendritic cells. The secreted enzyme can be detected from the blood circulation by recently developed immunoassays. In blood circulation, the enzyme exists as two isoforms, TRACP 5a with an intact polypeptide chain and TRACP 5b in which the polypeptide chain consists of two subunits. The 5b form is predominantly secreted by osteoclasts and is thus associated with bone turnover. The secretion of TRACP 5b is not directly related to bone resorption; instead, the levels are shown to be proportional to the number of osteoclasts. Therefore, the combination of TRACP 5b and a marker reflecting bone degradation, such as C-terminal cross-linked telopeptides of type I collagen (CTX), enables a more profound analysis of the changes in bone turnover. In this study, recombinant TRACP 5a-like protein was proteolytically processed into TRACP 5b-like two subunit form. The 5b-like form was more active both as an acid phosphatase and in producing reactive oxygen species, suggesting a possible function for TRACP 5b in osteoclastic bone resorption. Even though both TRACP 5a and 5b were detected in osteoclasts, serum TRACP 5a levels demonstrated no change in response to alendronate treatment of postmenopausal women. However, TRACP 5b levels decreased substantially, demonstrating that alendronate decreases the number of osteoclasts. This was confirmed in human osteoclast cultures, showing that alendronate decreased the number of osteoclats by inducing osteoclast apoptosis, and TRACP 5b was not secreted as an active enzyme from the apoptotic osteoclasts. In peripubertal girls, the highest levels of TRACP 5b and other bone turnover markers were observed at the time of menarche, whereas at the same time the ratio of CTX to TRACP 5b was lowest, indicating the presence of a high number of osteoclasts with decreased resorptive activity. These results support the earlier findings that TRACP 5b is the predominant form of TRACP secreted by osteoclasts. The major source of circulating TRACP 5a remains to be established, but is most likely other cells of the macrophage-monocyte system. The results also suggest that bone turnover can be differentially affected by both osteoclast number and their resorptive activity, and provide further support for the possible clinical use of TRACP 5b as a marker of osteoclast number.

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Irradiation of a,a-dimethylvalerophenone (1) adsorbed on microcrystalline cellulose employing methanol as the solvent shows a Norrish Type II/Type I ratio of 1.0±0.1. In solution, values of 2.3±0.3 in benzene and 8.7±2.0 in terc-butanol were obtained. The cyclization/elimination ratio for the Norrish Type II reaction of 1 shows values of 1.2±0.3 in cellulose, 17.9±2.7 in benzene and 3.2±03 in terc-butanol. When samples of 1/microcrystalline cellulose were prepared employing n-hexane, the Type II/Type I (29.5±2.9) and the cycl/elim (113.3±12.1) ratios were dramatically modified. These results demonstrate the difference in the behavior of 1 when entrapped in the cellulose chains or adsorbed on the cellulose surface.

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Rate constants for the quenching of 1,3-indandione (1) triplet by olefins and by hydrogen and electron donors were obtained employing the laser flash photolysis technique in benzene solution. These rate constants ranged from 2.5x10(5) Lmol-1s-1 (for 2-propanol) to 5.9x10(9) Lmol-1s-1 (for DABCO). From the quenching rate constants by 1,3-cyclohexadiene, trans- and cis-stilbene a value between 49.3 and 52.4 kcal/mol was estimated for the energy of the triplet state of 1,3-indandione. The npi* character of this triplet state was evidenced by the quenching rate constants obtained when typical hydrogen donors were employed as quenchers. For 2-phenyl-1,3-indandione (2, R=phenyl) a fast Norrish type I reaction is operating which prevents the determination of kinetic and spectroscopic data of its triplet state.

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Characterization of fish scales of Leporinus elongatus and their application in the removal of Cu(II) from aqueous solutions are described. It was observed that the scales are mainly formed by hydroxyapatite and type I collagen. Adsorption of Cu(II) was performed using batch experiments at 25 0C. The ANOVA statistical results have shown that the Langmuir model was successful applied to determine the maximum adsorption capacity of 2.686 x10-4 mol g-1 and the Langmuir equilibrium parameter (b) of 168.8 L mol-1. The Langmuir separation parameter, R L, has shown favorable adsorption of Cu(II) on the scales.

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Tapirira guianensis (Anacardiaceae) is used in traditional medicine and is important for the recovery of degraded areas and riparian forests because the T. guianensis fruits are highly consumed by wildlife. Volatile components from dried leaves and branches of five individual plants of T. guianensis were collected in two sandbank forests of the State of Pará (Extractive Reserve Maracanã and Area of Environmental Protection Algodoal/Maiandeua), extracted by hydrodistillation using a Clevenger-type apparatus, and analyzed by GC/MS. The ten oils obtained are comprised mostly of sesquiterpene hydrocarbons (58.49 to 100%), with (E)-caryophyllene, β-selinene, α-selinene, β-sesquiphellandrene, and α-zingiberene being the most prominent. The results of the oil compositions were processed by Hierarchical Component Analysis (HCA) allowing the establishment of three groups of essential oils for T. guianensis differentiated by the content of β-selinene/α-selinene (Type I), (E)-caryophyllene (Type II), and β-sesquiphellandrene/α-zingiberene (Type III).

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This work presents the results of a study on the hydration of pastes containing calcium hydroxide and either rice husk ash (RHA) or sugar cane bagasse ash (SCBA) in various initial CaO/SiO2 molar ratios. The products of the reactions were characterized by thermal analyses X-ray diffraction, and scanning electron microscopy. In the case of the RHA pastes, the product was composed of CaO-SiO2-H2O (type I C-S-H) or CaO-SiO2-H2O (type II C-S-H) according to the CaO/SiO2 ratio of the mixture. In contrast, in the case of the SBCA pastes, the product was composed primarily of CaO-SiO2-H2O that differed from both the previous types; the product also contained inclusions of calcium aluminate hydrates.

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Integrins are heterodimeric cell adhesion receptors involved in cell-cell and cell-extracellular matrix (ECM) interactions. They transmit bidirectional signals across the cell membrane. This results in a wide range of biological events from cell differentiation to apoptosis. alpha2beta1 integrin is an abundant collagen receptor expressed on the surface of several cell types. In addition to ECM ligands, alpha2beta1 integrins are bound by echovirus 1 (EV1) which uses alpha2beta1 as a receptor to initiate its life cycle in the infected cell. The aim of this thesis project was to provide further insight into the mechanisms of alpha2beta1 integrin ligand recognition and receptor activation. Collagen fibrils are the principal tensile elements of the ECM. Yet, the interaction of alpha2beta1 integrin with the fibrillar form of collagen I has received relatively little attention. This research focused on the ability of alpha2beta1 integrin to act as a receptor for type I collagen fibrils. Also the molecular requirements of the EV1 interaction with alpha2beta1 were studied. Conventionally, ligand binding has been suggested to require integrin activation and the binding may further trigger integrin signalling. Another main objective of this study was to elucidate both the inside-out and outside-in signalling mechanisms of alpha2beta1 integrin in adherent cells. The results indicated that alpha2beta1 integrin is the principal integrin-type collagen receptor for type I collagen fibrils, and alpha2beta1 may participate in the regulation of pericellular collagen fibrillogenesis. Furthermore, alpha2beta1 integrin inside-out activation appeared to be synergistically regulated by integrin clustering and conformational activation. The triggering of alpha2beta1 integrin outside-in signalling, however, was shown to require both conformational changes and clustering. In contrast to ECM ligands, EV1 appeared to take advantage of the bent, inactive form of alpha2beta1 integrin in initiating its life cycle in the cell. This research together with other recent studies, has shed light on the molecular mechanisms of integrin activation. It is becoming evident that large ligands are able to bind to the bent form of integrin, which has been previously considered to be physiologically inactive. Consequently, our understanding of the conformational modulation of integrins upon activation is changing.

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Photosystem II (PSII) is susceptible to light-induced damage defined as photoinhibition. In natural conditions, plants are capable of repairing the photoinhibited PSII by on-going degradation and re-synthesis of the D1 reaction centre protein of PSII. Photoinhibition is induced by both visible and ultraviolet light and photoinhibition occurs under all light intensities with the same efficiency per photon. In my thesis work, I studied the reaction kinetics and mechanism of photoinhibition of PSII, as well as photoprotection in leaves of higher plants. Action spectroscopy was used to identify photoreceptors of photoinhibition. I found that the action spectrum of photoinhibition <i>in vivoi> shows resemblance to the absorption spectra of manganese model compounds of the oxygen evolving complex (OEC) suggesting a role for manganese as a photoreceptor of photoinhibition under UV and visible light. In order to study the protective effect of non-photochemical quenching, the action spectrum was measured from leaves of wild type <i>Arabidopsis thalianai> and two mutants impaired in nonphotochemical quenching of chlorophyll a excitations. The findings of action spectroscopy and simulations of chlorophyll-based photoinhibition mechanisms suggested that quenching of antenna excitations protects less efficiently than would be expected if antenna chlorophylls were the only photoreceptors of photoinhibition. The reaction kinetics of prolonged photoinhibition was studied in leaves of <i>Cucurbita maximai> and <i> Capsicum annuumi>. The results indicated that photoinhibitory decrease in both the oxygen evolution activity and ratio of variable to maximum fluorescence follows firstorder kinetics <i>in vivoi>. The persistence of first-order kinetics suggests that already photoinhibited reaction centres do not protect against photoinhibition and that the mechanism of photoinhibition does not have a reversible intermediate. When <i>Cucurbita maximai> leaves were photoinhibited with saturating single-turnover flashes and continuous light, the light response curve of photoinhibition was found to be essentially a straight line with both types of illumination, suggesting that similar photoinhibition mechanisms might function during illumination with continuous light and during illumination with short flashes.

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The aim of this study was to investigate herpes simplex virus type 1 (HSV-1)- and measles virus (MV)-induced cell death. HSV-1 with deletion in genes encoding infected cell protein (ICP)4 and protein kinase Us3 (d120) induced apoptosis and cathepsin activation in epithelial (HEp-2) and monocytic (U937) cells. Inhibition of cathepsin activity decreased the amount of d120-induced apoptosis indicating that d120-induced apoptosis could be cathepsin-mediated. Also, HSV-1 infection increased caspase activation suggesting that d120-induced apoptosis is probably caspase-mediated. Cystatin treatment decreased the activity of cathepsins and the replication of HSV-1 indicating that cathepsins contribute to HSV-1 infection. Interestingly, d120 induced also necroptosis in monocytic cells. This is the first report on necroptosis in HSV-1- infected cells. MV induced apoptosis in uninfected bystander T lymphocytes, probably via interaction of MV-infected monocytes with uninfected lymphocytes. The expression of death receptor Fas was clearly increased on the surface of lymphocytes. The number of apoptotic cells and the activation of cathepsins and caspases were increased in MVinfected U937 cells suggesting that MV-induced apoptosis could be cathepsin- and caspase-mediated. Cystatin treatment inhibited cathepsin activities but not MV-induced apoptosis. Besides HSV-1-induced apoptosis, innate immune responses were studied in HSV-1-infection. HSV-1 viruses with either ICP4 and Us3, or Us3 deletion only, increased the expression of Toll-like receptor (TLR)3 and stimulated its downstream pathways leading to increased expression of type I interferon gene and to functional interferons. These findings suggest that besides controlling apoptosis, HSV-1 ICP4 and Us3 genes are involved in the control of TLR3 response in infected cell.

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Background: In Finland, breast cancer (BC) is the most common cancer among women, and prostate cancer (PC) that among men. At the metastatic stage both cancers remain essentially incurable. The goals of therapy include palliation of symptoms, improvement or maintenance of quality of life (QoL), delay of disease progression, and prolongation of survival. Balancing between efficacy and toxicity is the major challenge. With increasing costs of new treatments, appropriate use of resources is paramount. When new treatment regimes are introduced into clinical practice a comprehensive assessment of clinical benefit, adverse effects and cost is necessary. Both BC and PC show a predilection to metastasize to bone. Bone metastases cause significant morbidity impairing the patients´ QoL. Diagnosis of bone metastases relies mainly on radiological methods, which however lack optimal sensitivity and specificity. New tools are needed for detection and follow-up of bone metastases. Aims: Anthracyclines and taxanes are effective chemotherapeutic agents in the treatment of metastatic breast cancer (MBC) with different mechanisms of action. Therefore, evaluation of the combination of anthracyclines with taxanes was a justifiable approach in the treatment of MBC patients. We assessed the efficacy, toxicity, cost of treatment and QoL of BC patients treated with first-line chemotherapy for metastatic disease with the combination epirubicin and docetaxel. We also evaluated the diagnostic potential of tartrate-resistant acid phosphatase 5b (TRACP 5b) and carboxyterminal telopeptides of type I collagen (ICTP) in the diagnosis of bone metastases in BC and TRACP 5b in PC patients. Results: The combination of epirubicin and docetaxel was effective in this phase II study, but required individual dose adjustment to avoid neutropenic infections, and the use of growth factors to maintain a feasible dose level. The response rate was 54 % (95 % CI 37-71) and the median overall survival (OS) was 26 months. Of the patients, 87 % were treated for infections. The treatment of adverse events required additional use of health resources mainly due to neutropenic infections, thereby raising direct treatment costs by 20 %. Despite adverse events, the global QoL was not significantly compromised during the treatment. Clinically evident acute cardiac toxicity was not observed. The combination of serum TRACP 5b and ICTP was at least equally sensitive and specific in detection of of bone metastases as commonly used total alkaline phosphatise (tALP) in BC patients. In contrast, TRACP 5b was less specific and sensitive than tALP as a marker of skeletal changes in PC patients. Conclusions: Treatment with epirubicin and docetaxel showed high efficacy in first-line chemotherapy of MBC. The relatively high incidence of neutropenic infections requiring hospitalization increased the treatment costs. Despite adverse events, the global QoL of the patients was not significantly compromised. The combination of TRACP 5b and ICTP showed similar activity as tALP in detecting bone metastases in MBC. In contrast, TRACP 5b was less specific and sensitive than tALP as a marker of skeletal changes in PC.

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This study was conducted at the Agronomic Institute of Paraná (IAPAR) in Londrina, State of Paraná (PR), Brazil (latitude 23º18'S, longitude 51º09'W and average altitude of 585 m). The local climate, according to the classification of Köeppen, is Cfa type, i.e., humid subtropical climate, with rain in all seasons and can occur dry seasons during the winter. It was determined soil evaporation (E) under different coverage densities with residue from the wheat crop. The treatments were installed in weighting lysimeters of 2.66 m² and 1.3 m deep, which allows to determine E by the mass difference with measuring precision of 0.1mm at one hour intervals. Treatments consisted of 0; 2.5; 5 and 10 t ha-1 of wheat crop residues, placed evenly over each lysimeter. In the first cycle (September 22nd to October 20th, 2008), the reduction of E, as compared to a bare soil, was 4; 15 and 24%, while in the second cycle (December 1st to 30th, 2008), the reduction was of 15; 22 and 25%, respectively, for the treatments of 2.5; 5 and 10 t ha-1.

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The objective of the present study is to report a sucessful pregnancy in a 28 year-old female who underwent an orthotopic liver transplantation two years ago due to type I auto immune he patitis. Patient was taking cyclosporin, prednisone and azathioprine for maintenance immunossupression and had good graft function during all the pregnancy. The liver function tests were normal during the pregnancy. Fetal growth was monitored by ultrasonographic examination and showed normal development. At the end of the third trimester, she was subjected to a cesarean bearing a healthy girl weighting 2,320 kg. She was discharged with normal liver functions tests and no complications.

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We report the case of a one-year and two-months-old child with a choledochal cyst tYpe I of Alonso-Lej and Todani's classification , diagnosed through abdominal ultrasound. The surgical treatment was cholecistectomy and choledochal cyst excision with Roux-in-Y hepatic- jejunostomy. Minor complications were observed during early postoperative recovery. Long-term flow-up has been uneventiful, with overall improvement.