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Rigid polyurethane foam (PUr) is a common residue from the footwear industry that seeks a sustainable disposal alternative. A flexible composite incorporating PUr that could be used in this same industry is an exciting solution. Poly (vinyl chloride) (PVC) and polyvinyl butyral (PVB) were tested as possible matrixes for flexible composites containing 20%, 35%, and 50% of PUr produced by two different processes, extrusion and injection molding. PVB/PUr and PVC/PUr were compared considering the morphology observed with scanning electron microscopy (SEM), density, degradation during processing, and dynamical mechanical properties. PVC was severely degraded when processed with PUr and showed a low adhesion to PUr particles resulting in decreased storage modules and increased glass transition temperature. PVB is a better matrix for PUr flexible composites since it showed no sign of degradation and formed a stronger interface with PUr particles resulting in PVB/PUr composites with higher storage modulus.

Background: The hypothalamic proopiomelanocortin (Pomc) neurons act as first-order sensors of systemic energy stores, providing signals that regulate caloric intake and energy expenditure. In experimental obesity, dietary saturated fatty acids affect Pomc endopeptidases (PCs), resulting in the abnormal production of the neurotransmitters α-melanocyte-stimulating hormone (α-MSH) and β-endorphin, thus impacting energy balance. The cAMP response element-binding protein (CREB) is one of the transcription factors that control the expression of Pomc endopeptidases; however, it was previously unknown if dietary fats could affect CREB and consequently the expression of Pomc endopeptidases. Methods: Here, we used single-cell RNA sequencing analysis, PCR, immunoblot, ELISA and immunofluorescence histological assays to determine the impact of a high-fat diet (HFD) on the expression and function of hypothalamic CREB and its impact on the melanocortinergic system. Results: The results indicate that CREB is expressed in arcuate nucleus Pomc neurons and is activated as early as nine hours after the introduction of a high-fat diet. The inhibition of hypothalamic CREB using a short-hairpin RNA lentiviral vector resulted in increased diet-induced body-mass gain and reduced energy expenditure. This was accompanied by reduced expression of the Pomc endopeptidases, protein convertase 2, which are encoded by Pcsk2, and by the loss of the high-fat-diet-induced effect to inhibit the production of α-MSH. Conclusions: This study provides the first evidence for the involvement of CREB in the abnormal regulation of the hypothalamic Pomc endopeptidase system in experimental obesity.

To understand the processing influence in an intermeshing corotating twin-screw extrusion (ICTSE) on the morphology and impact properties of the uncompatibilized PBT/ABS (70/30) blend, it was submitted to different processing parameters. In this way both morphology and impact properties (resistance and ductile brittle transition temperature (DBTT) would be a function of processing only, because there would be no influence of a compatibilizer. The rotation speed of the screws influenced both impact resistance and Ductile Brittle Transition Temperature (DBTT) of the PBT/ABS blends. Blends prepared with higher rotation speed (240 rpm) did not present toughness at room temperature, whereas the blends prepared at lower speed showed high impact strength at room temperature and DBTT near to 5 °C. The angle between the kneading blocks discs also influenced the impact properties, because blends processed with screw with 90º angle between kneading block disks, for two different feed rates, showed lower DBTT than the blends processed with 45º angle. The morphological analysis by TEM showed that blends processed at low rotation speed of the screws presented a higher dispersion degree than those processed at high rotation speed. Blends processed in screws where the angle between the disks was 90º showed a higher dispersion degree than the blends processed in disks with a 45º angle. These results are in agreement with the impact properties, confirming that high dispersion of the ABS particles improves the impact properties of the blend.

In this study, the effects of the devulcanization process realized by an intermeshing co-rotating twin-screw extruder (ICTSE) on three vulcanized Natural Rubber (NR) composites with different crosslink densities (CD) have been investigated. The extrusion parameters were fixed, as well as the initial material granulometry and auxiliary thermoplastic added to the process. After composites vulcanization, they were characterized accordingly their soluble fraction (SF), crosslink density (CD), mechanical properties and thermogravimetry (TGA). The extrusion was performed on the vulcanized elastomers pursuing selectively crosslink rupture and the same characterization previously cited was conducted on the devulcanized material, except the mechanical properties analysis. The extrusion demonstrate effective devulcanization, evidenced in the increasing of soluble fractions, reduction in crosslink density and thermal stability gain. These results are directly affected by preliminary differences on materials structure and presence of ethylene vinyl-acetate (EVA) on extrusion.

Peripheral primitive neuroectodermal tumors (pPNETs) are part of the Ewing sarcoma family. A few more than 30 cases of pPNETs originating on the pancreas have been reported in the consulted literature. We report a locally advanced pancreatic pPNET, with the longest follow-up and survival in the consulted literature, considering quality of life outcomes. 22-year-old male patient, with a pancreatic pPNET comprising pancreatic body and tail with gastric invasion. He underwent multi organic resection and adjuvant chemotherapy and radiotherapy. After 8 years of follow-up, he was free of disease and with a good quality of life self-evaluation. The aggressive surgical approach associated with multimodal regimens provided improvement in disease-free survival and a positive impact on quality of life.

Obesity-derived inflammation and metabolic dysfunction has been related to the activity of the inducible nitric oxide synthase (iNOS). To understand the interrelation between metabolism, obesity and NO., we evaluated the effects of obesity-induced NO. signaling on liver mitochondrial function. We used mouse strains containing mitochondrial nicotinamide transhydrogenase activity, while prior studies involved a spontaneous mutant of this enzyme, and are, therefore, more prone to oxidative imbalance. Wild-type and iNOS knockout mice were fed a high fat diet for 2, 4 or 8 weeks. iNOS knockout did not protect against diet-induced metabolic changes. However, the diet decreased fatty-acid oxidation capacity in liver mitochondria at 4 weeks in both wild-type and knockout groups; this was recovered at 8 weeks. Interestingly, other mitochondrial functional parameters were unchanged, despite significant modifications in insulin resistance in wild type and iNOS knockout animals. Overall, we found two surprising features of obesity-induced metabolic dysfunction: (i) iNOS does not have an essential role in obesity-induced insulin resistance under all experimental conditions and (ii) liver mitochondria are resilient to functional changes in obesity-induced metabolic dysfunction.

Melatonin (Mel), a molecule that conveys photoperiodic information to the organisms, is also involved in the regulation of energy homeostasis. Mechanisms of action of Mel in the energy balance remain unclear; herein we investigated how Mel regulates energy intake and expenditure to promote a proper energy balance. Male Wistar rats were assigned to control, control + Mel, pinealectomized (PINX) and PINX + Mel groups. To restore a 24-h rhythm, Mel (1 mg/kg) was added to the drinking water exclusively during the dark phase for 13 weeks. After this treatment period, rats were subjected to a 24-h fasting test, an acute leptin responsiveness test and cold challenge. Mel treatment reduced food intake, body weight, and adiposity. When challenged to 24-h fasting, Mel-treated rats also showed reduced hyperphagia when the food was replaced. Remarkably, PINX rats exhibited leptin resistance; this was likely related to the capacity of leptin to affect body weight, food intake, and hypothalamic signal-transducer and activator of transcription 3 phosphorylation, all of which were reduced. Mel treatment restored leptin sensitivity in PINX rats. An increased hypothalamic expression of agouti-related peptide (Agrp), neuropeptide Y, and Orexin was observed in the PINX group while Mel treatment reduced the expression of Agrp and Orexin. In addition, PINX rats presented lower UCP1 protein levels in the brown adipose tissue and required higher tail vasoconstriction to get a proper thermogenic response to cold challenge. Our findings reveal a previously unrecognized interaction of Mel and leptin in the hypothalamus to regulate the energy balance. These findings may help to explain the high incidence of metabolic diseases in individuals exposed to light at night.

Obesity is a major risk factor for asthma, which is characterized by airway hyperreactivity (AHR). In obesity-associated asthma, AHR may be regulated by non-TH2 mechanisms. We hypothesized that airway reactivity is regulated by insulin in the CNS, and that the high levels of insulin associated with obesity contribute to AHR. We found that intracerebroventricular (ICV)-injected insulin increases airway reactivity in wild-type, but not in vesicle acetylcholine transporter knockdown (VAChT KDHOM−/−), mice. Either neutralization of central insulin or inhibition of extracellular signal-regulated kinases (ERK) normalized airway reactivity in hyperinsulinemic obese mice. These effects were mediated by insulin in cholinergic nerves located at the dorsal motor nucleus of the vagus (DMV) and nucleus ambiguus (NA), which convey parasympathetic outflow to the lungs. We propose that increased insulin-induced activation of ERK in parasympathetic pre-ganglionic nerves contributes to AHR in obese mice, suggesting a drug-treatable link between obesity and asthma.

This study reports the preparation and characterization of composites with recycled poly(vinyl butyral) (PVB) and residue of rigid polyurethane foam (PUr), with PUr contents of 20, 35 and 50 wt %, using an extruder equipped with a Maillefer single screw and injection molding. The components of the composites were thermally characterized using differential scanning calorimetry (DSC) and thermogravimetry. The composites were evaluated by melt flow index (MFI), tensile and hardness mechanical tests and scanning electron microscopy (SEM). Tg determined by DSC of PVB sample (53 °C) indicated the presence of plasticizer (Tg of pure PVB is 70 °C). MFI of the composites indicated a viscosity increase with the PUr content and, as the shear rate was held constant during injection molding, higher viscosities promoted higher shear stresses in the composites, thereby causing breaking or tearing of the PUr particles. The SEM micrographs showed low adhesion between PVB and PUr and the presence of voids, both inherent in the rigid foam and in the interphase PVB-PUr. The SEM micrographs also showed that PVB/PUr (50/50) composite exhibited the smallest particle size and a more homogeneous and compact structure with fewer voids in the interface. The stiffness of the composites increases with addition of the PUr particles, as evidenced in the mechanical tests.

Poly(butylene terephthalate) (PBT)/ acrylonitrile-butadiene-styrene (ABS) terpolymer blends were prepared in a twin screw extruder and the use of methyl methacrylate-glycidyl methacrylate-ethyl acrylate (MGE) terpolymer as compatibilization additive was evaluated. The effect of different screw profiles and mixing conditions were evaluated on the crystallization of the blends. Differential scanning calorimetry (DSC) was used to evaluate melting and crystallization behaviors of the PBT/ABS blends. The binary PBT/ABS blend has shown a double melting peak when cooled at lower cooling rates, mainly due to its melt-recrystallization during the heating up step. ABS has not affected the melting characteristics of neat PBT. The presence of MGE, as a reactive compatibilizer, in the PBT/ABS blends has reduced its heat of fusion and has partially inhibited its melt-recrystallization under heating. As result, it has prevented the occurrence of double melting peak. The epoxy functional groups of the MGE may react in situ to the carbonyls and hydroxyls end groups of the PBT molecules, thereby hindering the mobility of PBT molecules during the crystallization process due to its grafting to the compatibilizer molecules. The melt mixed blends prepared at lower feeding rate have shown a higher degree of crystallinity for the PBT/ABS blend, probably due to degradation of PBT caused by longer residence time in the extruder. The highest shear stress imposed to the blends at higher screw speed increased the degree of crystallinity of PBT, also due to its degradation.

Summary Introduction: Extramedullary plasmacytoma is a plasma cell tumor that grows within any of the soft tissues of the organism. Similar to all plasmacytic dyscrasia, the disease is extremely rare. Aim: This study reports a case of an extramedullary plasmacytoma of the nasal cavity and provides a literature review on the topic. Case report: A 51-year-old woman presented at our tertiary university hospital with a 6-month history of progressive nasal obstruction, predominantly to the right side, and self-limiting epistaxis. Examination revealed a large pale-reddish tumor within the right nasal cavity. Anatomopathological analysis showed features consistent with a plasmacytoma diagnosis, which was subsequently confirmed by immunohistochemical techniques. Further assessment revealed the solitary nature of the condition, consistent with extramedullary plasmacytoma. Radiotherapy was initiated, which led to partial regression of the symptoms. The tumor was surgically removed by using a mid-facial degloving approach. The patient evolved with a naso-oral fistula and underwent 3 corrective surgeries. No evidence of associated systemic disease was found after 5 years of follow-up. Conclusions: This case report, which describes a rare tumor of the nasal cavity, is expected to improve the recognition and referral of this condition by ear, nose, and throat (ENT) specialists for multidisciplinary management and long-term follow-up.

Summary Introduction: Paragangliomas are neuroendocrine tumors that most commonly originate in the adrenal gland, a type that is called pheochromocytoma; however, 5–10% of paragangliomas are extra-adrenal and may arise in any area between the neck and pelvic region along the sympathetic nervous system. Those located in the head and neck comprise 3% of extra-adrenal tumors, with the majority originating in the tympanic–jugular region and carotid body. Objective: To present a rare case of nasal paraganglioma and review the literature. Case report: The patient was submitted to medial subtotal maxillectomy, and her clinical findings, diagnostic data, and treatment outcome were recorded. Conclusion: Paragangliomas are considered benign tumors, but they occasionally display a malignant character. The most important finding in this case was the need for total resection of the tumor to avoid recurrence.

Os autores tecem considerações sobre a estrutura e funções normais das glândulas paratireóides como introdução à patologia e as repercussões clinico - patológicas tanto do excesso como da redução do paratormônio. Maior ênfase é dedicada ao hiperparatireoidismo primário quanto às causas, a fisiopatologia das alterações, os aspectos anatomopatológicos macro e microscópicos das lesões e sua patogenia, na "Osteite fibrocistica" ou "doença de von Recklinghausen dos ossos" com a correlação aos aspectos radiográficos. Apresentam caso de paciente, cuja história clinica demonstra as dificuldades encontradas para o diagnóstico da doença. Referem-se ainda às alterações e patogenia das formas de hiperparatireoidismo secundário e terciário e ao hipoparatireoidismo.The authors present a summary on the normal anatomy and function of the parathyroid glands as well as a brief review of clinical and pathological repercussions of higher and lower parathyroid hormone production. The emphasis is given on the causes, physiopathology, anatomy, macroscopy and microscopy of the lesions and their role in the genesis of fibrocystic osteitis, also known as Von Recklinhausen disease of the bones. Radiological correlation is also given. The authors show the challenges for the diagnosis in the same cases. We also write about secondary and tertiary hyperparathyroidism, as well as hypoparathyroidism.

OBJETIVOS: Estudar retrospectivamente 18 casos de pacientes com adamantinoma de ossos longos, todos localizados na tíbia; ressaltar a importância da biópsia e a correlação com métodos de imagem para diagnóstico diferencial com osteofibrodisplasia e displasia fibrosa; tecer considerações sobre a natureza do adamantinoma de ossos longos, cujo nome deve-se à analogia histológica com o adamantinoma (ameloblastoma) da mandíbula. MÉTODOS: Foram analisados o quadro clínico, imagens e exames anatomopatológicos complementados com imunohistoquímica e a evolução dos pacientes. Todos foram submetidos a tratamento cirúrgico, 17 com "tibialização" da fíbula e os demais com amputação. RESULTADOS: A evolução pós-cirúrgica mostrou-se imprevisível e não relacionada com os aspectos clínicos ou histopatológicos. Dois pacientes evoluíram com metástases pulmonares e morreram. Seis não tiveram recidivas ou metástases e estão clinicamente curados. Os demais, após alta hospitalar não retornaram à consulta. CONCLUSÕES: Trata-se de rara neoplasia constituída por estruturas epiteliais e mesenquimais que devem ser diagnosticadas com precisão, antes de qualquer procedimento. O tratamento é cirúrgico com ressecção do tumor com boa margem oncológica. O comportamento biológico é variável e imprevisível.OBJECTIVE: To make a retrospective study of 18 cases of patients with adamantinoma of the long bone, all of them located in the tibia; to point to the relevance of biopsy and the correlation with imaging methods in order to have a differential diagnosis with osteofibrous dysplasia and fibrous dysplasia; to comment on the nature of long bone adamantinoma, whose name is due to the histological analogy with the adamantinoma (ameloblastoma) of the jaw. METHODS: A review was made of the clinical condition, images, and anatomopathological exams supplemented with immunohistochemical essays, and the evolution of the patients. All of them were submitted to surgical treatment, 17 with "tibialization" of the fibula and the others with amputation. RESULTS: The post-surgical evolution showed to be unpredictable and not related to clinical or histopathological aspects. Two patients had an evolution with lung metastasis and died. Six did not present recurrent disease or metastases, and are clinically cured. The others, after being released from hospital, did not return for consultation. CONCLUSIONS: This is a rare neoplasia made of epithelial and mesenchymal structures that must be accurately diagnosed before any procedure is attempted. Treatment is surgical, with tumor resection with a good oncologic margin. The biological behavior is varied and unpredictable.

In the present paper we report a case of mediastinal tumor which we believe has never been reported. Since surgical treatment, the patient presented good evolution. We discuss the presentation, differential diagnosis and therapy. Finally, we stress the importance of the pathologic findings.

CONTEXTO: O fibrohistiocitoma benigno intra-ósseo é uma neoplasia rara, caracterizada por proliferação fibroblástica e fibras colágenas. A dor na região lombar é uma queixa freqüente em muitos pacientes, mas, na maioria das vezes está relacionada com causa muscular ou degenerativa. RELATO DE CASO: Relata-se aqui o caso de um paciente com diagnóstico de fibrohistiocitoma benigno ósseo na coluna lombar que apresentava queixa de lombalgia há cinco meses antes do diagnóstico. Foi submetida à biópsia aberta transpedicular na quarta vértebra lombar ,e, posteriormente realizada curetagem da lesão via anterior retroperitonial e artrodese vertebral de L3-L5 com enxerto de fíbula. CONCLUSÃO: Apesar de raro, o fibrohistiocitoma benigno intra-ósseo deve ser uma das hipóteses quando observamos uma lesão primária na coluna vertebral.CONTEXT: Benign intraosseous fibrous histiocytoma is a rare neoplasia, characterized by fibroblastic and collagenous fiber proliferation. Pain in the lumbar region is a frequent complaint in many patients, but most of times it is associated to muscular or degenerative causes. CASE REPORT: Here we report a case of a patient diagnosed with benign bone fibrous histiocytoma in the lumbar spine who complained of lumbar pain dating five months prior to diagnosis. The patient was submitted to open transpedicular biopsy in the forth lumbar vertebra, and subsequently, lesion curettage was performed via anterior retroperitoneal and L3-L5 vertebral arthrodesis using a fibular graft. CONCLUSION: Although rare, benign intraosseous fibrohistiocytoma should be taken into consideration when a primary lesion is observed in the spine.

ABSTRACT Objectives: To determine the role of immunohistochemistry in identifying the primary site of tumors, and in establishing which bones are most frequently involved, their relationship with the primary tumor site, and the rate of pathologic bone fracture as the first symptom of a malignant tumor. Methods: A retrospective analysis of all medical records on bone metastases the cases treated between January 2006 and December 2011 at the Department of Orthopedics and Traumatology was performed. Results: Immunohistochemistry correctly determined the primary tumor site in 61.2% of cases analyzed. Regarding the metastatic site, the most affected bone was the femur, accounting for 49.6% of the sample. Bone metastasis was the first symptom of the tumor in only 20.2% of patients, and of these, 95% were admitted for pathologic bone fracture. Conclusion: The study showed that the primary sites and their incidence rate are consistent with the literature reviewed. It was noted that in this sample, most patients did not present with pathologic bone fracture as the first clinical symptom of neoplastic disease. However, analysis of those patients that had a metastasis as the first clinical symptom revealed that it manifested itself as a pathologic fracture in almost all cases. The immunohistochemical study was consistent with the primary tumor site in most cases, indicating the value of the method in the detection of the primary site.

In the present paper we report a case of mediastinal tumor which we believe has never been reported. Since surgical treatment, the patient presented good evolution. We discuss the presentation, differential diagnosis and therapy. Finally, we stress the importance of the pathologic findings.

While inflammation is a crucial response in injury repair and tissue regeneration, chronic inflammation is a prevalent feature in various chronic, non-communicable diseases such as obesity, diabetes, and cancer and in cardiovascular and neurodegenerative diseases. Long-term inflammation considerably affects disease prevalence, quality of life, and longevity. Our research indicates that the growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis is a pivotal regulator of inflammation in some tissues, including the hypothalamus, which is a key player in systemic metabolism regulation. Moreover, the GH/IGF-1 axis is strongly linked to longevity, as GH- or GH receptor-deficient mice live approximately twice as long as wild-type animals and exhibit protection against aging-induced inflammation. Conversely, GH excess leads to increased neuroinflammation and reduced longevity. Our review studies the associations between the GH/IGF-1 axis, inflammation, and aging, with a particular focus on evidence suggesting that GH receptor signaling directly induces hypothalamic inflammation. This finding underscores the significant impact of changes in the GH axis on metabolism and on the predisposition to chronic, non-communicable diseases.

In utero exposure to maternal obesity programs increased obesity risk. Animal models show that programmed offspring obesity is preceded by hyperphagia, but the mechanisms that mediate these changes are unknown. Using a mouse model of maternal obesity, we observed increased intake of a high-fat diet (HFD) in offspring of obese mothers that precedes the development of obesity. Through small RNA sequencing, we identified programmed overexpression of hypothalamic miR-505-5p that is established in the fetus, lasts to adulthood and is maintained in hypothalamic neural progenitor cells cultured in vitro. Metabolic hormones and long-chain fatty acids associated with obesity increase miR-505-5p expression in hypothalamic neurons in vitro. We demonstrate that targets of miR-505-5p are enriched in fatty acid metabolism pathways and overexpression of miR-505-5p decreased neuronal fatty acid metabolism in vitro. miR-505-5p targets are associated with increased BMI in human genetic studies. Intra-cerebroventricular injection of miR-505-5p in wild-type mice increased HFD intake, mimicking the phenotype observed in offspring exposed to maternal obesity. Conversely, maternal exercise intervention in an obese mouse pregnancy rescued the programmed increase of hypothalamic miR-505-5p in offspring of obese dams and reduced HFD intake to control offspring levels. This study identifies a novel mechanism by which maternal obesity programs obesity in offspring via increased intake of high-fat foods.