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51.
Nuno Marques Ana Lebre Francisco Marques Maria Julião Luís Freitas Lurdes Malcata Eduardo Rabadão José Saraiva da Cunha 《Mycopathologia》2013,176(1-2):89-93
The authors report a clinical case of an isolated oral histoplasmosis in a hemodialysis patient that presented with fever of unknown origin and had an unremarkable physical examination. During the investigation, a Gallium scan showed uptake in the oral cavity and soon after the oral cavity examination revealed a granulomatous lesion on the tooth 26. Histopathologic findings were compatible with histoplasmosis. The treatment regimen included liposomal amphotericin B followed by itraconazole consolidation therapy, and side effects did not occur. Both clinical evolution and outcome were favorable. Oral histoplasmosis in a non-immunosuppressed patient is extremely rare. 相似文献
52.
Rosane Aparecida Ribeiro Sandra Lucinei Balbo Letícia Prates Roma Rafael Ludemann Camargo Luiz Felipe Barella Emerielle Cristine Vanzela Paulo Cesar de Freitas Mathias Everardo Magalhães Carneiro Antonio Carlos Boschero Maria Lúcia Bonfleur 《Molecular biology reports》2013,40(7):4521-4528
Monosodium glutamate-obese rats are glucose intolerant and insulin resistant. Their pancreatic islets secrete more insulin at increasing glucose concentrations, despite the possible imbalance in the autonomic nervous system of these rats. Here, we investigate the involvement of the cholinergic/protein kinase (PK)-C and PKA pathways in MSG β-cell function. Male newborn Wistar rats received a subcutaneous injection of MSG (4 g/kg body weight (BW)) or hyperosmotic saline solution during the first 5 days of life. At 90 days of life, plasma parameters, islet static insulin secretion and protein expression were analyzed. Monosodium glutamate rats presented lower body weight and decreased nasoanal length, but had higher body fat depots, glucose intolerance, hyperinsulinemia and hypertrigliceridemia. Their pancreatic islets secreted more insulin in the presence of increasing glucose concentrations with no modifications in the islet-protein content of the glucose-sensing proteins: the glucose transporter (GLUT)-2 and glycokinase. However, MSG islets presented a lower secretory capacity at 40 mM K+ (P < 0.05). The MSG group also released less insulin in response to 100 μM carbachol, 10 μM forskolin and 1 mM 3-isobutyl-1-methyl-xantine (P < 0.05, P < 0.0001 and P < 0.01). These effects may be associated with a the decrease of 46 % in the acetylcholine muscarinic type 3 (M3) receptor, and a reduction of 64 % in PKCα and 36 % in PKAα protein expressions in MSG islets. Our data suggest that MSG islets, whilst showing a compensatory increase in glucose-induced insulin release, demonstrate decreased islet M3/PKC and adenylate cyclase/PKA activation, possibly predisposing these prediabetic rodents to the early development of β-cell dysfunction. 相似文献
53.
Résumé Ce travail retrace les événements qui ont conduit à une collaboration exemplaire entre entomologistes enançais et américains (principalement le professeur C. V. Riley) pendant la crise du Phylloxera en France, grâce aux nombreuses archives existant de part et d’autre de I’Atlantique. Une des premiéres questions a été de savoir si le Phylloxera était identique dans les deux pays, prouvant ainsi son origine américaine. Une autre question a été de savoir si ce parasite était la cause ou la conséquence de la maladie de la vigne. Cette question, primordiale car lourde de conséquences sur les plans économique et politique, a vu s’afenonter certains entomologistes enançais (le professeur J. E. Planchon et J. Lichtenstein), tenant de I’hypothèse causale, à ?autres (V. A. Signoret) qui soutenaient que le puceron ne s’installait que sur des vignes malades. II s’est établi une collaboration remarquable entre les entomologistes enançais et C. V. Riley, qui a pu apporter des résultats très convaincants à la thèse causale. Enfin son rôle a été déterminant pour conforter la seule solution à long terme défendue par Planchon et Lichtenstein : la greffe de la vigne enançaise sur des vignes américaines résistantes. 相似文献
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55.
Fernanda Luna da Silva Eduardo Coelho Cerqueira Mônica Santos de Freitas Daniela Leão Gonçalves Lilian Terezinha Costa Cristian Follmer 《Neurochemistry international》2013
In the last decades, a series of compounds, including quinones and polyphenols, has been described as having anti-fibrillogenic action on α-synuclein (α-syn) whose aggregation is associated to the pathogenesis of Parkinson’s disease (PD). Most of these molecules act as promiscuous anti-amyloidogenic agents, interacting with the diverse amyloidogenic proteins (mostly unfolded) through non-specific hydrophobic interactions. Herein we investigated the effect of the vitamins K (phylloquinone, menaquinone and menadione), which are 1,4-naphthoquinone (1,4-NQ) derivatives, on α-syn aggregation, comparing them with other anti-fibrillogenic molecules such as quinones, polyphenols and lipophilic vitamins. Vitamins K delayed α-syn fibrillization in substoichiometric concentrations, leading to the formation of short, sheared fibrils and amorphous aggregates, which are less prone to produce leakage of synthetic vesicles. In seeding conditions, menadione and 1,4-NQ significantly inhibited fibrils elongation, which could be explained by their ability to destabilize preformed fibrils of α-syn. Bidimensional NMR experiments indicate that a specific site at the N-terminal α-syn (Gly31/Lys32) is involved in the interaction with vitamins K, which is corroborated by previous studies suggesting that Lys is a key residue in the interaction with quinones. Together, our data suggest that 1,4-NQ, recently showed up by our group as a potential scaffold for designing new monoamine oxidase inhibitors, is also capable to modulate α-syn fibrillization in vitro. 相似文献
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57.
Background
The diagnosis of idiopathic pulmonary fibrosis can be quite challenging, even after careful clinical evaluation, imaging and pathological tests. This case report intends to demonstrate and discuss these difficulties, especially those concerning the differential diagnosis with chronic hypersensitivity pneumonitis.Case presentation
A 58-year-old white male presented with shortness of breath, dry cough, fatigue and weight loss for two months. He was a former smoker and had regular exposure to a parakeet and poultry. Physical examination revealed bilateral basal crackles and chest imaging showed subpleural cystic lesions and traction bronchiectasis with a right side and upper level predominance. Auto-antibodies and IgG immunoglobulins to parakeet and fungal proteins were negative. Lung function tests displayed moderate restriction, low diffusion capacity and resting hypoxaemia. Bronchoalveolar lavage showed increased lymphocytes (28%) and neutrophils (12%) and surgical lung biopsy was compatible with a pattern of usual interstitial pneumonia. According to the possibility of either idiopathic pulmonary fibrosis or chronic hypersensitivity pneumonitis, treatment included prednisolone, azathioprine, acetylcysteine and avoidance of contact with the parakeet, but there was an unfavorable response and the patient was subsequently referred for lung transplant.Conclusion
Chronic hypersensitivity pneumonitis and idiopathic pulmonary fibrosis can present with the same clinical and radiological manifestations In this case, despite careful evaluation, no definite diagnosis could be achieved.58.
Parathyroidectomy Improves Survival In Patients with Severe Hyperparathyroidism: A Comparative Study
Patricia Taschner Goldenstein Rosilene Motta Elias Lilian Pires de Freitas do Carmo Fernanda Oliveira Coelho Luciene Pereira Magalh?es Gisele Lins Antunes Melani Ribeiro Custódio Fábio Luiz de Menezes Montenegro Silvia Maria Titan Vanda Jorgetti Rosa Maria Affonso Moysés 《PloS one》2013,8(8)
Background and objectives
Secondary hyperparathyroidism (SHPT) in CKD is associated with an increased risk for mortality, but definitive data showing that parathormone control decreases mortality is still lacking. This study aimed to compare the mortality of patients with severe SHPT submitted to parathyroidectomy(PTX) with those who did not have access to surgery.Methods
This is a retrospective study in a cohort of 251 CKD patients with severe SHPT who were referred to a CKD-MBD Center for PTX from 2005 until 2012.Results
Most of our patients had indication of PTX, but only 49% of them had access to this surgical procedure. After a mean follow-up of 23 months, 72 patients had died. Non-survivors were older; more often had diabetes, lower serum 25 vitamin D and mostly had not been submitted to surgery. The relative risk of death was lower in the PTX patients (0.428; 95% CI, 0.28 to 0.67; p<0.0001). After adjustments, mortality risk was dependent on age (1.04; 95% CI, 1.01 to 1.07; p = 0.002), 25 vitamin D (0.43; 95% CI, 0.24 to 0.81; p = 0.006) and no access to PTX (4.13; 95% CI, 2.16 to 7.88; p<0.0001). Results remained the same in a second model using the PTX date as the study start date for the PTX group.Conclusions
Our data confirms the benefit of PTX on mortality in patients with severe SHPT. The high mortality encountered in our population is significant and urges the need to better treat these patients. 相似文献59.
Land-use change and global warming are important factors driving bee decline, but it is largely unknown whether these drivers have resulted in changes in the life-history traits of bees. Recent studies have shown a stronger population decline of large- than small-bodied bee species, suggesting there may have been selective pressure on large, but not on small species to become smaller. Here we test this hypothesis by analyzing trends in bee body size of 18 Dutch species over a 147-year period using specimens from entomological collections. Large-bodied female bees shrank significantly faster than small-bodied female bees (6.5% and 0.5% respectively between 1900 and 2010). Changes in temperature during the flight period of bees did not influence the size-dependent shrinkage of female bees. Male bees did not shrink significantly over the same time period. Our results could imply that under conditions of declining habitat quantity and quality it is advantageous for individuals to be smaller. The size and sex-dependent responses of bees point towards an evolutionary response but genetic studies are required to confirm this. The declining body size of the large bee species that currently dominate flower visitation of both wild plants and insect-pollinated crops may have negative consequences for pollination service delivery. 相似文献
60.
Evaluation of dental enamel caries assessment using Quantitative Light Induced Fluorescence and Optical Coherence Tomography 下载免费PDF全文
Ana Marly Araújo Maia Anderson Zanardi de Freitas Sergio de L. Campello Anderson Stevens Leônidas Gomes Lena Karlsson 《Journal of biophotonics》2016,9(6):596-602
An in vitro study of morphological alterations between sound dental structure and artificially induced white spot lesions in human teeth, was performed through the loss of fluorescence by Quantitative Light‐Induced Fluorescence (QLF) and the alterations of the light attenuation coefficient by Optical Coherence Tomography (OCT). To analyze the OCT images using a commercially available system, a special algorithm was applied, whereas the QLF images were analyzed using the software available in the commercial system employed. When analyzing the sound region against white spot lesions region by QLF, a reduction in the fluorescence intensity was observed, whilst an increase of light attenuation by the OCT system occurred. Comparison of the percentage of alteration between optical properties of sound and artificial enamel caries regions showed that OCT processed images through the attenuation of light enhanced the tooth optical alterations more than fluorescence detected by QLF System.