928 resultados para spontaneous vesicle
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The physical exercise consists of trainable physical abilities such as strength and endurance. It can be inferred that the individual cardiac patient is dependent on it as an associated therapy to the drug treatment for a rapid and lasting improvement of their overall clinical status. The patient - with Spontaneous Coronary Artery Dissection Postpartum period - was subjected to 21 sessions of cardiac rehabilitation. A physical evaluation was performed, before and after the treatment period, for data collection: anthropometric values, flexibility, aerobic capacity and strength of grip. The patient had a positive response in aerobic capacity, flexibility and grip strength and the anthropometric values were kept in short term rehabilitation.
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Many adverse pregnancy outcomes (APOs), including spontaneous preterm birth (PTB), are associated with placental dysfunction. Recent clinical and experimental evidences suggest that premature aging of the placenta may be involved in these events. Although placental aging is a well-known concept, the mechanisms of aging during normal pregnancy and premature aging in APOs are still unclear. This review was conducted to assess the knowledge on placental aging related biochemical changes leading to placental dysfunction in PTB and/or preterm premature rupture of membranes (pPROM). We performed a systematic review of studies published over the last 50 years in two electronic databases (Pubmed and Embase) on placental aging and PTB or pPROM. The search yielded 554 citations, 30 relevant studies were selected for full-text review and three were included in the review. Only one study reported oxidative stress-related aging and degenerative changes in human placental membranes and telomere length reduction in fetal cells as part of PTB and/or pPROM mechanisms. Similarly, two animal studies reported findings of decidual senescence and referred to PTB mechanisms. Placental and fetal membrane oxidative damage and telomere reduction are linked to premature aging in PTB and pPROM but the risk factors and biomolecular pathways causing this phenomenon are not established in the literature. However, no biomarkers or clinical indicators of premature aging as a pathology of PTB and pPROM have been reported. We document major knowledge gaps and propose several areas for future research to improve our understanding of premature aging linked to placental dysfunction.
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Livestock poisoning by plants is a frequent occurrence which determines severe losses, such as the fall in the milk and meat production, the cost of expensive treatments, the state of immunosuppression, or even the animal's death. Cattle ingest toxic plants only when there is food shortage, when they cannot select what they eat, or when they ingest food for preference, which is the case of Hovenia dulcis fruits, very rich in sucrose. This plant is widely distributed in the southern and southeastern Brazilian regions. In literature, there are some cases of severe human liver injury associated with a long-term of H. dulcis leaf and fruit tea intake, and only one report regarding spontaneous poisoning of goats caused by this plant ingestion. However, its toxic effects associated with spontaneous ingestion by cattle have never been reported. This paper reports the first case of spontaneous poisoning in cattle by H. dulcis, which occurred in a dairy farm in southwest Paraná, Brazil. Three cattle individuals showed anorexia, ruminal atony, severe diarrhea and neurological tournament, head pressing, blindness, ataxia, and circling. The necropsy of the animals was done, and the remaining alterations were restricted to the digestive system and brain. The clinical signs presented by the animals are characteristic of polioencephalomalacia (PEM), caused by changes in the thiamine metabolism. Furthermore, clinical signs, gross, and microscopic lesions as well as the large amount of the plant throughout the digestive segment led to a diagnosis.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Neurofibromatosis type 1 (NF1) is an autosomal dominant multisystem disorder affecting approximately 1 in 3500 individuals. Patients with the disorder can develop carcinoid tumors, medullary thyroid carcinoma, pheochromocytoma and tumor of the hypothalamus. The association of NF1 with Primary Hyperparathyroidism (HPP) is very rare. We report a 56-year-old woman with NF1 who was referred to our service because of nephrolithiasis. Physical examination revealed the characteristic signs of NF1, and her laboratory calcium profile was compatible with HPP. The patient was referred for parathyroidectomy, but during the surgical work-up she underwent spontaneous remission of her HPP. This case is significant not only for the rarity of this presentation in NF1 patients, but also because of the spontaneous remission of HPP.
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Objective: To investigate the follicular size at spontaneous rupture on pregnancy rate in patientswith polycystic ovary syndrome (PCOS) undergoing clomiphene citrate (CC) ovulation.Design: Cross-sectional study.Patients and methods: One hundred and four women with ovulatory cycles after use of CCfollowed by ultrasound to determine the follicle size at the time of rupture, which wassubsequently correlated with the occurrence of pregnancy or not in coit cycles.Results: In the group of follicular rupture at a mean diameter25 mm (n¼54), pregnancy ratewas 35.1% and when follicular rupture occurred at a mean diameter425 mm (n¼50), it was34% (p40.05). When different diameters at follicular rupture were randomly correlated with thepregnancy rate, there was no significant difference.Conclusion: Our data suggest that the occurrence of pregnancy after ovulation induction withCC in women with PCOS is not associated with follicle size at the time of rupture.
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Spontaneous intracerebral hemorrhage (SICH) is responsible for 10%-15% of the acute stroke. Hematoma or the occlusion of cerebrospinal fluid (CSF) flow by ventricular clotting can result in obstructive hydrocephalus, increasing intracranial pressure, which needs urgent decompression. We report our results of management of spontaneous deep cerebral hematoma by endoscopic approach.
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Using theoretical arguments, a simple scaling law for the size of the intrinsic rotation observed in tokamaks in the absence of a momentum injection is found: The velocity generated in the core of a tokamak must be proportional to the ion temperature difference in the core divided by the plasma current, independent of the size of the device. The constant of proportionality is of the order of 10 km . s(-1) . MA . keV(-1). When the intrinsic rotation profile is hollow, i.e., it is countercurrent in the core of the tokamak and cocurrent in the edge, the scaling law presented in this Letter fits the data remarkably well for several tokamaks of vastly different size and heated by different mechanisms.
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Stress is the most commonly reported precipitating factor for seizures in patients with epilepsy. Despite compelling anecdotal evidence for stress-induced seizures, animal models of the phenomena are sparse and possible mechanisms are unclear. Here, we tested the hypothesis that increased levels of the stress-associated hormone corticosterone ( CORT) would increase epileptiform activity and spontaneous seizure frequency in mice rendered epileptic following pilocarpine-induced status epilepticus. We monitored video-EEG activity in pilocarpine-treated mice 24/7 for a period of four or more weeks, during which animals were serially treated with CORT or vehicle. CORT increased the frequency and duration of epileptiform events within the first 24 hours of treatment, and this effect persisted for up to two weeks following termination of CORT injections. Interestingly, vehicle injection produced a transient spike in CORT levels - presumably due to the stress of injection - and a modest but significant increase in epileptiform activity. Neither CORT nor vehicle treatment significantly altered seizure frequency; although a small subset of animals did appear responsive. Taken together, our findings indicate that treatment of epileptic animals with exogenous CORT designed to mimic chronic stress can induce a persistent increase in interictal epileptiform activity.
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This report focuses on the 2005 Annual meeting held in Caxambu, Minas Gerais, Brazil that was convened and organized by the Brazilian Society of Protozoology http://www.sbpz.org.br/. This is an annual event and details of these meetings can be found on the Society's website. Within the space available it has been impossible to cover all the important and fascinating contributions and what is presented are our personal views of the meetings scientific highlights and new developments. The contents undoubtedly reflect each author's scientific interests and expertise. Fuller details of the round tables, seminars and posters can be consulted on line at http://www.sbpz.org.br/livroderesumos2005.php.
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Abstract Introduction Pelvicalyceal cysts are common findings in autopsies and can manifest with a variety of patterns. These cystic lesions are usually a benign entity with no clinical significance unless they enlarge enough to cause compression of the adjacent collecting system and consequently obstructive uropathy. Few cases of the spontaneous rupture of pelvicalyceal renal cysts have been published and to the best of our knowledge there is no report of a combined rupture to collector system and retroperitoneal space documented during a multiphase computed tomography. Case presentation We report a case of a ‘real-time’ spontaneous rupture of a pelvicalyceal cyst into the collecting system with fistulization into the retroperitoneum. The patient was a 78-year-old Caucasian man with a previous history of renal stones and a large pelvicalyceal renal cyst who was admitted to our Emergency department with acute right flank pain. A multiphase computed tomography was performed and the pre-contrast images demonstrated a right pelvicalyceal renal cyst measuring 12.0 × 6.1cm in the lower pole causing moderate dilation of the upper right renal collection system. In addition, a partially obstructive stone on the left distal ureter with mild left hydronephrosis was noted. The nephrographic phase did not add any new information. The excretory phase (10-minute delay) demonstrated a spontaneous rupture of the cyst into the pelvicalyceal system with posterior fistulization into the retroperitoneal space. Conclusion In this case study we present time-related changes of a rare pelvicalyceal cyst complication, which to the best of our knowledge has fortunately not been previously documented. Analysis of the sequential images and comparison with an earlier scan allowed us to better understand the physiopathological process of the rupture, the clinical presentation and to elaborate hypotheses for its etiopathogenesis.
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The effect of angiotensin II (ANG II) or arginine vasopressin (AVP) alone or plus atrial natriuretic peptide (ANP) on H+-ATPase subcellular vesicle trafficking was investigated in MDCK cells following intracellular pH (pHi) acidification by exposure to20 mMNH4Cl for 2 min in a Na+-free solution containing Schering 28080, conditions under which H+-AT-Pase is the only cell mechanism for pHi recovery. Using the acridine orange fluorescent probe (5mM) and confocal microscopy, the vesicle movement was quantified by determining, for each experimental group, the mean slope of the line indicating the changes in apical/basolateral fluorescence density ratio over time during the first 5.30 min of the pHi recovery period. Under the control conditions, the mean slope was 0.079 ± 0.0033 min-1 (14) and it increased significantly with ANG II [10-12 and 10-7 M, respectively to 0.322 ± 0.038 min-1 (13) and 0.578 ± 0.061 min-1 (12)] or AVP [10-12 and 10-6 M, respectively to 0.301 ± 0.018 min-1 (12) and 0.687 ± 0.049 min-1 (11)]. However, in presence of ANP (10-6 M, decreases cytosolic free calcium), dimethyl-BAPTA/AM (5 × 10-5 M, chelates intracellular calcium) or colchicine (10-5 M, 2-h preincubation; inhibits microtubule-dependent vesicular trafficking) alone or plus ANG II or AVP the mean slopes were similar to the control values, indicating that such agents blocked the stimulatory effect of ANG II or AVP on vesicle trafficking. The results suggest that the pathway responsible for the increase in cytosolic free calcium and the microtu-bule-dependent vesicular trafficking are involved in this hormonal stimulating effect. Whether cytosolic free calcium reduction represents an important direct mechanism for ANP impairs the dose-dependent stimulatory effect of ANG II or AVP on H+-ATPase subcellular vesicle trafficking, or is a side effect of other signaling pathways which will require additional studies.
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Tetraspan vesicle membrane proteins (TVPs) sind ubiquitäre Komponenten von Transportvesikeln. Bei den Säugetieren unterscheidet man drei Familien, die Physine, Gyrine und SCAMPs (secretory carrier-associated membrane proteins). Ihre Funktion ist weitgehend unbekannt, es wird jedoch vermutet, dass sie eine Rolle bei der Vesikelbildung und der Vesikelrezirkulierung spielen. In Caenorhabditis elegans existiert von jeder Familie jeweils nur ein einziges Polypeptid: für die Physine Synaptophysin (SPH-1), für die Gyrine Synaptogyrin (SNG-1) und für die SCAMPs SCAMP (SCM-1). Ziel der Arbeit war es die Verteilung der C. elegans TVPs zu untersuchen und ihre Funktion unter besonderer Berücksichtigung der vesikelvermittelten synaptischen Kopplung zu bestimmen. Wenn die C. elegans TVPs in humanen Epithelzellen synthetisiert werden, lokalisieren sie in zytoplasmatischen Vesikeln. In Kotransfektionsexperimenten wurde gezeigt, dass sie größtenteils in den gleichen Strukturen enthalten sind. In C. elegans synthetisierte TVP-Reporterkonstrukte können in unterschiedlichen Geweben nachgewiesen werden. Dabei ist SNG-1 fast ausschließlich in Neuronen zu finden. SPH-1 und SCM-1 hingegen weisen komplexe und teilweise überlappende Verteilungsmuster auf. Während für SPH-1 eine starke Fluoreszenz im Pharynx, auf der apikalen Seite der Darmzellen oberhalb des sog. terminal webs und in adluminalen Regionen von exkretorischen Geweben gefunden wurde, war SCM-1 stark in der Muskulatur und den Coelomozyten vertreten. Die Expression von SCM-1 in Pharynx und Darm war deutlich schwächer. Die C. elegans TVPs werden früh in der Entwicklung ab der Gastrulation (SPH-1 und SCM-1) bzw. ab der Neurulation im sog. Komma-Stadium (SNG-1) produziert. Um die Funktion der TVPs in C. elegans zu untersuchen, wurden TVP-Mutanten analysiert. Durch Kombination aller drei TVP-Gen-Mutanten wurden TVP-Dreifachmutanten generiert. Diese wiesen keinen offensichtlichen Defekt im Bewegungsmuster auf, entwickelten sich normal und bildeten ein normales Nervensystem aus. Auch auf unterschiedliche chemische und physikalische Reize in sensorischen Tests reagierten die TVP-Dreifachmutanten in gleicher Weise wie Wildtyptiere. Ebenso zeigen die TVP-Dreifachmutanten elektrophysiologisch unter normalen Bedingungen keine anormalen Reaktionsmuster. In ultrastrukturellen Untersuchungen wurde lediglich eine signifikant erhöhte Anzahl Clathrin-ummantelter Vesikel in cholinergen Synapsen gefunden. Erst unter Stressbedingungen, hervorgerufen durch den GABA-Antagonisten Pentylentetrazol (PTZ), wiesen sowohl die TVP-Dreifach- als auch die TVP-Einzelmutanten eine deutlich erhöhte Krampfbereitschaft auf. Zusammengenommen zeigen die Analysen, dass TVPs zwar für grundlegende neuronale Prozesse nicht notwendig sind, dass sie aber auf der anderen Seite vermutlich an alternativen redundanten Wegen der Neurotransmitterfreisetzung beteiligt sind.
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Materials that can mold the flow of elastic waves of certain energy in certain directions are called phononic materials. The present thesis deals essentially with such phononic systems, which are structured in the mesoscale (<1 µm), and with their individual components. Such systems show interesting phononic properties in the hypersonic region, i.e., at frequencies in the GHz range. It is shown that colloidal systems are excellent model systems for the realization of such phononic materials. Therefore, different structures and particle architectures are investigated by Brillouin light scattering, the inelastic scattering of light by phonons.rnThe experimental part of this work is divided into three chapters: Chapter 4 is concerned with the localized mechanical waves in the individual spherical colloidal particles, i.e., with their resonance- or eigenvibrations. The investigation of these vibrations with regard to the environment of the particles, their chemical composition, and the influence of temperature on nanoscopically structured colloids allows novel insights into the physical properties of colloids at small length scales. Furthermore, some general questions concerning light scattering on such systems, in dispute so far, are convincingly addressed.rnChapter 5 is a study of the traveling of mechanical waves in colloidal systems, consisting of ordered and disordered colloids in liquid or elastic matrix. Such systems show acoustic band gaps, which can be explained geometrically (Bragg gap) or by the interaction of the acoustic band with the eigenvibrations of the individual spheres (hybridization gap).rnWhile the latter has no analogue in photonics, the presence of strong phonon scatterers, when a large elastic mismatch between the composite components exists, can largely impact phonon propagation in analogy to strong multiple light scattering systems. The former is exemplified in silica based phononic structures that opens the door to new ways of sound propagation manipulation.rnChapter 6 describes the first measurement of the elastic moduli in newly fabricated by physical vapor deposition so-called ‘stable organic glasses’. rnIn brief, this thesis explores novel phenomena in colloid-based hypersonic phononic structures, utilizing a versatile microfabrication technique along with different colloid architectures provided by material science, and applying a non-destructive optical experimental tool to record dispersion diagrams.rn
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During the perinatal period the developing brain is most vulnerable to inflammation. Prenatal infection or exposure to inflammatory factors can have a profound impact on fetal neurodevelopment with long-term neurological deficits, such as cognitive impairment, learning deficits, perinatal brain damage and cerebral palsy. Inflammation in the brain is characterized by activation of resident immune cells, especially microglia and astrocytes whose activation is associated with a variety of neurodegenerative disorders like Alzheimer´s disease and Multiple sclerosis. These cell types express, release and respond to pro-inflammatory mediators such as cytokines, which are critically involved in the immune response to infection. It has been demonstrated recently that cytokines also directly influence neuronal function. Glial cells are capable of releaseing the pro-inflammatory cytokines MIP-2, which is involved in cell death, and tumor necrosis factor alpha (TNFalpha), which enhances excitatory synaptic function by increasing the surface expression of AMPA receptors. Thus constitutively released TNFalpha homeostatically regulates the balance between neuronal excitation and inhibition in an activity-dependent manner. Since TNFalpha is also involved in neuronal cell death, the interplay between neuronal activity MIP-2 and TNFalpha may control the process of cell death and cell survival in developing neuronal networks. An increasing body of evidence suggests that neuronal activity is important in the regulation of neuronal survival during early development, e.g. programmed cell death (apoptosis) is augmented when neuronal activity is blocked. In our study we were interested on the impact of inflammation on neuronal activity and cell survival during early cortical development. To address this question, we investigated the impact of inflammation on neuronal activity and cell survival during early cortical development in vivo and in vitro. Inflammation was experimentally induced by application of the endotoxin lipopolysaccharide (LPS), which initiates a rapid and well-characterized immune response. I studied the consequences of inflammation on spontaneous neuronal network activity and cell death by combining electrophysiological recordings with multi-electrode arrays and quantitative analyses of apoptosis. In addition, I used a cytokine array and antibodies directed against specific cytokines allowing the identification of the pro-inflammatory factors, which are critically involved in these processes. In this study I demonstrated a direct link between inflammation-induced modifications in neuronal network activity and the control of cell survival in a developing neuronal network for the first time. Our in vivo and in vitro recordings showed a fast LPS-induced reduction in occurrence of spontaneous oscillatory activity. It is indicated that LPS-induced inflammation causes fast release of proinflammatory factors which modify neuronal network activity. My experiments with specific antibodies demonstrate that TNFalpha and to a lesser extent MIP-2 seem to be the key mediators causing activity-dependent neuronal cell death in developing brain. These data may be of important clinical relevance, since spontaneous synchronized activity is also a hallmark of the developing human brain and inflammation-induced alterations in this early network activity may have a critical impact on the survival of immature neurons.