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New World porcupines (Erethizontidae) exhibit behaviors and possess integumentary structures, including the quills, that are used for self-defense. The North American porcupine (Erethizon dorsatum) has been well studied regarding these features; however, information is lacking for the South American Coendou species. We describe the defensive behavior and integumentary morphology of Coendou spinosus to understand the defensive strategies of this species and to compare with those reported for other species. We assessed the behaviors related to warning, defense, and escape of eight porcupines, as well as the characteristics of their pelage and quills. Furthermore, we microscopically analyzed skin samples of a roadkill adult male specimen. Similar to E. dorsatum, C. spinosus exhibited omnidirectional quill erection, revealing an aposematic color and, with their backs toward the perceived human threat, they performed quick tail and body movements to strike the hands of the human trying to capture them by the tail. Furthermore, C. spinosus presented an integumentary structure similar to that of E. dorsatum, and mechanisms to facilitate quill release when touched, penetration, and fixation in the opponent. The most distinct warning behavior noted was the vibration of the quills, which has not been reported for Erethizon. Our study confirms that, like other erethizontids, C. spinosus does not attack but exhibits warning, defense, and escape mechanisms and behaviors when threatened or touched. The dissemination of such information helps to counter the negative stigma associated with porcupines, as they can be the victims of attacks by dogs and humans, and to promote their conservation.
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Comportamento Animal , Porcos-Espinhos , Animais , Porcos-Espinhos/anatomia & histologia , Porcos-Espinhos/fisiologia , Masculino , Comportamento Animal/fisiologia , Tegumento Comum/anatomia & histologia , Tegumento Comum/fisiologia , Feminino , Pele/anatomia & histologiaRESUMO
Aging disrupts brain function, leading to cognitive decline and neurodegenerative diseases. Senescent astrocytes, a hallmark of aging, contribute to this process through unknown mechanisms. This study investigates how senescence impacts astrocytic mitochondrial dynamics, which are critical for brain health. Our research, conducted using aged mouse brains, represents the first evidence of morphologically damaged mitochondria in astrocytes, along with functional alterations in mitochondrial respiration. In vitro experiments revealed that senescent astrocytes exhibit an increase in mitochondrial fragmentation and impaired mitophagy. Concurrently, there was an upregulation of mitochondrial biogenesis, indicating a compensatory response to mitochondrial damage. Importantly, these senescent astrocytes were more susceptible to mitochondrial stress, a vulnerability reversed by rapamycin treatment. These findings suggest a potential link between senescence, impaired mitochondrial quality control, and increased susceptibility to mitochondrial stress in astrocytes. Overall, our study highlights the importance of addressing mitochondrial dysfunction and senescence-related changes in astrocytes as a promising approach for developing therapies to counter age-related neurodegeneration and improve brain health.
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Astrócitos , Senescência Celular , Mitocôndrias , Mitofagia , Astrócitos/metabolismo , Astrócitos/patologia , Animais , Mitofagia/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Camundongos , Senescência Celular/efeitos dos fármacos , Envelhecimento/patologia , Envelhecimento/metabolismo , Camundongos Endogâmicos C57BL , Masculino , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Dinâmica Mitocondrial/efeitos dos fármacosRESUMO
Introduction: Dengue virus (DENV), the etiologic agent of dengue fever illness, represents a global public health concern, mainly in tropical and subtropical areas across the globe. It is well known that this acute viral disease can progress to severe hemorrhagic stages in some individuals, however, the immunopathogenic basis of the development of more severe forms by these patients is yet to be fully understood. Objective: In this context, we investigated and characterized the histopathological features as well as the cytokine profile and cell subpopulations present in liver tissues from three fatal cases of DENV in children. Methods: Hematoxylin and Eosin, Periodic Acid Schiff and Picro Sirius Red staining were utilized for the histopathological analysis. Immunohistochemistry assay was performed to characterize the inflammatory response and cell expression patterns. Results: Vascular dysfunctions such as hemorrhage, vascular congestion and edema associated with a mononuclear infiltrate were observedin all three cases. Liver tissues exhibited increased presence of CD68+ and TCD8+ cells as well as high expression of MMP-9, TNF-a, RANTES, VEGFR-2 mediators. Viral replication was confirmed by the detection of NS3 protein. Conclusion: Taken together, these results evidenced key factors that may be involved in the development of severe alterations in liver tissues of children in response to DENV infection.
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Vírus da Dengue , Dengue , Humanos , Criança , Mediadores da Inflamação/metabolismo , Antígenos Virais/metabolismo , Fígado/patologiaRESUMO
In this case report, we demonstrate how the correct positioning of implants, associated with optimal gingival conditioning, and the correct choice of biomaterial can yield very predictable and fantastic aesthetic results. OBJECTIVE: We aimed to use dental implants to rehabilitate the area of elements #11 and #21 in a satisfactory surgical and prosthetic manner, using guided surgery, connective tissue, nano-biomaterials, and a porcelain prosthesis. CASE REPORT: A 32-year-old male patient presented with bone loss of elements #11 and #21, which was proven radiographically and clinically. Thus, oral rehabilitation with the use of dental implants was required. It was decided to proceed via digital planning with the DSD program (Digital smile design) and with the software Exoplan, (Smart Dent-Germany) whenever it was possible to plan immediate provisional and accurate dental implant positioning through reverse diagnostics (Software Exoplan, Smart Dent-German). The dental elements were extracted atraumatically; then, a guide was established, the implants were positioned, the prosthetic components were placed, the conjunctive tissue was removed from the palate and redirected to the vestibular wall of the implants, the nano-graft (Blue Bone®) was conditioned in the gaps between the vestibular wall and the implants, and, finally, the cemented provision was installed. RESULTS: After a 5-month accompaniment, an excellent remodeling of the tissues had been achieved by the implants; consequently, the final prosthetic stage could begin, which also achieved a remarkable aesthetic result. CONCLUSIONS: This report demonstrates that the correct planning of dental implants, which is associated with appropriate soft tissue and bone manipulation, allows for the achievement of admirable clinical results.
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Dengue virus (DENV) infection represents a worldwide public health concern and can cause damage to multiple organs, including the kidney. In this work, we investigated the histopathological changes caused by dengue virus infection along with the detection of inflammatory mediators, cytokines, and cell expression patterns in the renal tissue of three fatal cases in children. Hematoxylin and Eosin staining was performed to analyze these histopathological changes. Immunohistochemistry allowed for the detection of immunological inflammatory markers in renal tissues that were quantified and further analyzed. Vascular congestion, edema and glomerular infiltrate were observed in the three cases, in addition to the thickening of the matrix area around the glomerular capillaries and mononuclear infiltrate associated with vascular congestion in the medullary region. The renal tissues exhibited collagen deposition and high expression of CD68+ Mø, CD8+ T, CD56+ cells and MMP-9, and the cytokine profile was mainly characterized by the expression of IFN-γ and TNF-α. Additionally, the expression of RANTES, VEGFR-2 and VCAM-1 were observed. The replication of DENV was evidenced by the detection of the NS3 protein. These results contributed to clarifying the main factors that may be involved in changes in the renal tissue of fatal cases of dengue in children.
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SARS-CoV-2 is a virus that belongs to the Betacoronavirus genus of the Coronaviridae family. Other coronaviruses, such as SARS-CoV and MERS-CoV, were associated with complications in pregnant women. Therefore, this study aimed to report the clinical history of five pregnant women infected with SARS-CoV-2 (four symptomatic and one asymptomatic who gave birth to a stillborn child) during the COVID-19 pandemic. They gave birth between August 2020 to January 2021, a period in which there was still no vaccination for COVID-19 in Brazil. In addition, their placental alterations were later investigated, focusing on macroscopic, histopathological, and ultrastructural aspects compared to a prepandemic sample. Three of five placentas presented SARS-CoV-2 RNA detected by RT-PCRq at least two to twenty weeks after primary pregnancy infection symptoms, and SARS-CoV-2 spike protein was detected in all placentas by immunoperoxidase assay. The macroscopic evaluation of the placentas presented congested vascular trunks, massive deposition of fibrin, areas of infarctions, and calcifications. Histopathological analysis showed fibrin deposition, inflammatory infiltrate, necrosis, and blood vessel thrombosis. Ultrastructural aspects of the infected placentas showed a similar pattern of alterations between the samples, with predominant characteristics of apoptosis and detection of virus-like particles. These findings contribute to a better understanding of the consequences of SARS-CoV-2 infection in placental tissue, vertical transmission.
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COVID-19 , Complicações Infecciosas na Gravidez , Feminino , Fibrina , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Pandemias , Placenta , Gravidez , RNA Viral , SARS-CoV-2 , Glicoproteína da Espícula de CoronavírusRESUMO
Dengue viral (DENV) infections can lead to acute pancreatitis and associated tissue damage. This study examined the pancreas from two fatal cases of DENV for histopathological changes as well as for the detection of cytokines, and other inflammatory mediators. Tissue sections were prepared for examination by ultrastructural and histopathological techniques. Sections from the pancreas of non-infected individuals were prepared in parallel as a control. The presence of viral replication in macrophages was detected by co-staining for the proteins NS3 and CD68 by immunofluorescence. Immunohistochemistry was used to detect cells that expressed cytokines and inflammatory mediators to characterize the inflammatory response. Edema, acinar necrosis and fibrosis areas associated with a mononuclear infiltrate were found in infected tissues. The major site of virus replication appeared to be macrophages based on their exclusive presentation of the viral protein NS3. Pancreatic tissues from the infected individuals also displayed increased levels of high mobility group box-1, caspase-3, gelatinase B and tumor necrosis factor alpha compared to controls. The presence of virus replicating macrophages in the pancreas was associated with multiple changes in tissue structure that included elevated levels of cytokines and inflammatory markers that may differentiate acute pancreatitis due to DENV infections from other causes.
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Biomarcadores/metabolismo , Citocinas/metabolismo , Vírus da Dengue/isolamento & purificação , Dengue/complicações , Mediadores da Inflamação/metabolismo , Pancreatite/patologia , Adulto , Apoptose , Dengue/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/metabolismo , Pancreatite/virologia , Adulto JovemRESUMO
In this work, in vitro testing was used to study the properties of non-crosslinked type 1 bovine derived collagen membranes used in bone regeneration surgery. Collagen membranes were prepared, their surface roughness was quantified by interferometry, their morphology was observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), their wettability was measured by the contact angle technique, their mechanical properties were investigated by tensile testing, their phase transformation temperatures were measured by Differential Scanning Calorimetry (DSC), and their biocompatibility was evaluated by immunological testing. The calorimetry tests showed that the membrane is formed only by type 1 collagen. The SEM observations showed that the morphology consists of layers of highly organized collagen fibers and patterns of striated fibrils typical of type 1 collagen. The small contact angle showed that the membrane is hydrophilic, with the possibility of rapid absorption of body fluids. The tensile tests showed that the membrane has enough elasticity, ductility, and mechanical strength for use in tissue regeneration. With the immunostaining technique, it was possible to confirm the membrane biocompatibility.
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BACKGROUND: The development of techniques in biomaterials design and production added to advanced surgical procedures which enabled better and more predictable clinical outcomes. Maxillary sinus floor augmentation (MSFA) is among the more studied bone-guided regeneration procedure in the literature. The MSFA could be considered the gold standard procedure for bone-guided regeneration as it provides suitable functional and aesthetic solutions to alveolar ridge atrophy due to tooth loss. PURPOSE: This study aimed to conduct a detailed histomorphometric evaluation of collagen production in SFAs bone-guided regeneration, using nano-hydroxyapatite/ß-tricalcium phosphate (nano-HA/ß-TCP) composite. PATIENTS AND METHODS: A 52-year-old female had the left upper second premolar condemned due to periodontal disease, then a tooth implant replacement was planned. Due to maxillary sinus pneumatization, the MSFA had to be done before implant placement. Nano-HA/ß-TCP composite (2g) was used in the MSFA procedure. After nine months of the healing process, during the Cone Morse implant installation process, bone samples were collected for histologic analysis (sirius red, hematoxylin/eosin, polarized microscopy). Six months after implant installation, a ceramic crown was installed according to the patient's request. RESULTS: Proper masticatory function and aesthetics were re-established. The histomorphometric evaluation indicated that nano-HA/ß-TCP composite did not show any area devoid of cellular activity in sirius red or hematoxylin/eosin staining and the percentage (%) of new bone collagen fibers was achieved using polarization technique evaluation. CONCLUSION: According to these results, nano-HA/ß-TCP composite presented clinical and histomorphometric properties suit to be used as bone-guided regeneration biomaterial in MSFA. Furthermore, nano-HA/ß-TCP composite provided a favorable nano-environment to bone cells, enhancing bone matrix production.
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Bone defects are a challenging clinical situation, and the development of hydroxyapatite-based biomaterials is a prolific research field that, in addition, can be joined by stem cells and growth factors in order to deal with the problem. This study compares the use of synthetic hydroxyapatite and xenograft, used pure or enriched with bone marrow mononuclear fraction for the regeneration of critical size bone defects in rat calvaria through histomorphometric (Masson's staining) and immunohistochemical (anti-VEGF, anti-osteopontin) analysis. Forty young adult male rats were divided into five groups (n = 8). Animals were submitted to critical size bone defects (Ø = 8 mm) in the temporoparietal region. In the control group, there was no biomaterial placement in the critical bone defects; in group 1, it was filled with synthetic hydroxyapatite; in group 2, it was filled with xenograft; in group 3, it was filled with synthetic hydroxyapatite, enriched with bone marrow mononuclear fraction (BMMF), and in group 4 it was filled with xenograft, enriched with BMMF. After eight weeks, all groups were euthanized, and histological section images were captured and analyzed. Data analysis showed that in groups 1, 2, 3 and 4 (received biomaterials and biomaterials plus BMMF), a significant enhancement in new bone matrix formation was observed in relation to the control group. However, BMMF-enriched groups did not differ from hydroxyapatite-based biomaterials-only groups. Therefore, in this experimental model, BMMF did not enhance hydroxyapatite-based biomaterials' potential to induce bone matrix and related mediators.
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Studies suggest that the bioactive polyphenolic compound resveratrol (RESV, trans-isomer), found naturally in certain foods such as red grapes and peanuts, may be able to ameliorate liver damage. However, the effects and efficacy of long-term treatment with RESV remain unclear. Here, we used an acetaminophen (APAP; 400 mg/kg/d for 15 days) overdose model to induce liver damage in C56BL/6 mice. Three days after the intoxication was stopped, we observed biochemical, histological and ultrastructural alterations in the livers of these mice. The APAP-treated animals were then given RESV (10 mg/kg/d) for 60 days. Blood and tissue were analyzed at days 7, 30 and 60. Our data show that long-term RESV treatment (60 days) ameliorates the liver injury caused by APAP intoxication, restoring histological features, ultrastructural organization and serum biochemical parameters (albumin, alanine aminotransferase). Ck18- and F4/80-positive cells (indicators of hepatocyte recovery) were reestablished and the number of α-SMA positive cells was normalized after long-term RESV treatment. Additionally, downregulation of the drug transporter BCRP was observed. Electron microscopy revealed that treatment with RESV was effective in restoring the shape and size of hepatic microvilli and normalizing both the number and viability of mitochondria. Taken together, these results indicate that long-term treatment with RESV is effective in alleviating liver injury caused by APAP administration.
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Doença Hepática Induzida por Substâncias e Drogas , Regeneração Hepática , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Animais , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias , Resveratrol/farmacologiaRESUMO
PURPOSE: Maternal nicotine exposure negatively impacts offspring's health and metabolism, leading to obesity and insulin resistance. Here we investigated the pancreatic islet function, glycemic homeostasis, and insulin signaling in adult rat offspring that were nicotine-exposed during breastfeeding. METHODS: For this, lactating Wistar rat dams were divided into two groups: Nicotine (implanted with osmotic minipumps containing 6 mg/Kg, NIC) and Control (saline, CON). Solutions were released from postnatal (PN) day 2-16. At PN110 and PN170, 10 offspring per litter/sex/group were submitted to the oral glucose tolerance test (OGTT). PN180 offspring were killed and glycemia, insulinemia, adiponectinemia, pancreas morphology as well as pancreatic islet protein expression (related to insulin secretion) and skeletal muscle (related to insulin action) were evaluated. Males and females were compared to their respective controls. RESULTS: Adult NIC offspring of both sexes showed glucose intolerance in the OGTT. Despite normoglycemia, NIC males showed hyperinsulinemia while females, although normoinsulinemic, had hyperglycemia. Both sexes showed increased IRI, reduced adiponectin/visceral fat mass ratio and higher ectopic deposition of lipids in the pancreatic tissue adipocytes. In pancreatic islets, NIC males showed lower PDX-1 expression while females had higher PDX-1 and GLUT2 expressions plus lower α2 adrenergic receptor. In the muscle, NIC offspring of both sexes showed reduction of GLUT4 expression; NIC males also had lower insulin receptor and pAKT expressions. CONCLUSIONS: Thus, glycemic homeostasis and peripheral insulin signaling in adult offspring of both sexes are affected by nicotine exposure through the milk, increasing the risk for type 2 diabetes development.
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Diabetes Mellitus Tipo 2 , Nicotina , Animais , Feminino , Insulina , Lactação , Masculino , Nicotina/toxicidade , Pâncreas , Ratos , Ratos WistarRESUMO
Nowadays, we can observe a worldwide trend towards the development of synthetic biomaterials. Several studies have been conducted to better understand the cellular mechanisms involved in the processes of inflammation and bone healing related to living tissues. The aim of this study was to evaluate tissue behaviors of two different types of biomaterials: synthetic nano-hydroxyapatite/beta-tricalcium phosphate composite and bone xenograft in sub-critical bone defects in rat calvaria. Twenty-four rats underwent experimental surgery in which two 3 mm defects in each cavity were tested. Rats were divided into two groups: Group 1 used xenogen hydroxyapatite (Bio Oss™); Group 2 used synthetic nano-hydroxyapatite/beta-tricalcium phosphate (Blue Bone™). Sixty days after surgery, calvaria bone defects were filled with biomaterial, animals were euthanized, and tissues were stained with Masson's trichrome and periodic acid-Schiff (PAS) techniques, immune-labeled with anti-TNF-α and anti-MMP-9, and electron microscopy analyses were also performed. Histomorphometric analysis indicated a greater presence of protein matrix in Group 2, in addition to higher levels of TNF-α and MMP-9. Ultrastructural analysis showed that biomaterial fibroblasts were associated with the tissue regeneration stage. Paired statistical data indicated that Blue Bone™ can improve bone formation/remodeling when compared to biomaterials of xenogenous origin.
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In Brazil, an epidemic of Zika virus (ZIKV) infections was declared in 2015 that coincided with alarming reports of microcephaly in newborns associated with mother infection. Although the virus has placental tropism, changes in the tissue morphology and immunity of infected patients have not yet been elucidated. Here, we investigated the histopathological and ultrastructural changes along with the immunological profile and the BDNF expression in rare placental material. Tissues were obtained in the 2015-2016 Brazilian epidemic, of ten ZIKV-infected patients during pregnancy, five resulting in cases of fetal microcephaly and five non-microcephaly, compared to five non-infected control placentae. Viral antigens were only detected in samples from the ZIKV infected patients. Infected placentae presented histopathological severe damage, while the ultrastructural evaluation showed abnormal organelles, such as clusters of virus-like particles consistent with the ZIKV dimensions. Increased infiltration of CD68+ and TCD8+ cells, expression of MMPs, cytokines (IFN-γ and TNF-α) and other immunological mediators (RANTES/CCL5 and VEGFR-2) confirmed excessive inflammation and vascular permeability dysfunction. An evaluation of BDNF showed a decrease that could modulate neuronal damage in the developing fetus. The placental changes caused by ZIKV are not pathognomonic, however, the data provide evidence that this infection leads to severe placental injury.
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Microcefalia/etiologia , Placenta/patologia , Complicações Infecciosas na Gravidez/patologia , Infecção por Zika virus/patologia , Zika virus/patogenicidade , Adulto , Antígenos Virais/análise , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Fator Neurotrófico Derivado do Encéfalo/genética , Brasil/epidemiologia , Estudos de Casos e Controles , Cesárea , Colágeno/biossíntese , Colágeno/genética , Citocinas/biossíntese , Citocinas/genética , Surtos de Doenças , Feminino , Humanos , Corpos de Inclusão Viral , Recém-Nascido , Masculino , Metaloproteinases da Matriz/biossíntese , Metaloproteinases da Matriz/genética , Placenta/metabolismo , Placenta/virologia , Gravidez , Complicações Infecciosas na Gravidez/metabolismo , Complicações Infecciosas na Gravidez/virologia , Trofoblastos/ultraestrutura , Trofoblastos/virologia , Replicação Viral , Adulto Jovem , Zika virus/imunologia , Zika virus/isolamento & purificação , Zika virus/fisiologia , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/imunologiaRESUMO
The purpose of this study was to examine whether the supplementation with an açai (Euterpe oleracea Mart.) seed extract (ASE) would affect the aerobic exercise performance in rats and correlate with the vascular function, muscle oxidative stress and mitochondrial biogenesis. Male Wistar rats were divided into five groups: Sedentary, Sedentary with chronic supplementation of ASE, Training, Training with chronic (200 mg/Kg/day intragastric gavage for 5 weeks) or acute (30 min before the maximal treadmill stress test (MST) supplementation with ASE. The exercise training was performed on a treadmill (30 min/day; 5 days/week) for 4 weeks. The chronic supplementation with ASE increased the exercise time (58%) and the running distance (129%) in relation to the MST, while the Training group increased 40% and 78% and the Training with acute ASE group increased 30% and 63%, respectively. The training-induced increase of ACh vasodilation was not changed by ASE, but the norepinephrine-induced vasoconstriction was reduced by chronic and acute supplementation with ASE. The increased levels of malondialdehyde in soleus muscle homogenates from the Training group was reduced only by chronic supplementation with ASE. The muscle antioxidant defense, NO2 levels, and expression of the mitochondrial biogenesis-related proteins (PGC1α, SIRT-1, p-AMPK/AMPK, Nrf-2) were not different between Training and Sedentary groups, but all these parameters were increased in the Training with Chronic ASE compared with the Sedentary groups. In conclusion, chronic supplementation with ASE improves aerobic physical performance by increasing the vascular function, reducing the oxidative stress, and up-regulating the mitochondrial biogenesis key proteins.
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Euterpe , Animais , Antioxidantes , Masculino , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , SementesRESUMO
Mitochondria (m) are responsible for the energy availability of cells, and their analysis is indicated for example, in studies related to metabolism and oxidative stress. The direct measurement of mitochondria (morphometry) is biased because of the section obliquity and position relative to the mitochondria length (non-equatorial cut). Therefore, stereology is an appropriate technique to evaluate mitochondria. However, before beginning the study, it is necessary to consider the premises to obtain random and uniform samples to be analyzed stereology. Mitochondria must have the chance to appear in all the possibilities of cut and orientation in the micrographs. The number of micrographs to be analyzed will depend on the distribution and occupation of mitochondria in the cell. After this is resolved, a proposal is the estimation of the following stereological data: volume density (Vv), surface density (Sv), and mean cross-sectional area (A). Overlapping a known test area at each micrograph, the density by area of mitochondria is estimated (NAT). Vv [m] can easily be estimated by point-counting (Vv = Pp/PT; Pp are the points hitting the structure, PT are the number of points of the test system). Sv is estimated overlaying a test-line (LT) on the micrographs and counting the intersections of the lines (I) with the outer membrane (om), inner membrane (im), and crests (c), thus, Sv [om], Sv [im], Sv [c] (Sv = 2I / LT). A [m] is obtained as the ratio: A = Vv / 2NAT.
Las mitocondrias (m) son responsables de la disponibilidad de energía de las células, y su análisis está indicado, por ejemplo, en estudios relacionados con el metabolismo y el estrés oxidativo. La medición directa de las mitocondrias (morfometría) está sesgada debido a la oblicuidad de la sección y la posición relativa a la longitud de las mitocondrias (corte no ecuatorial). Por lo tanto, la estereología es una técnica apropiada para evaluar las mitocondrias. Sin embargo, antes de comenzar el estudio, es necesario considerar las premisas para obtener muestras aleatorias y uniformes para analizar estereológicamente. Es esencial que las mitocondrias tengan la posibilidad de aparecer en todas las posibilidades de corte y orientación en las micrografías. El número de micrografías que se analizarán dependerá de la distribución y ocupación de las mitocondrias en la célula. Una vez resuelto esto, una propuesta es la estimación de los siguientes datos estereológicos: densidad de volumen (Vv), densidad de superficie (Sv) y área de sección transversal media (A). Superponiendo un área de prueba conocida en cada micrografía, se estima la densidad por área de mitocondrias (NAT). Vv [m] se puede estimar fácilmente contando puntos (Vv = Pp / PT; Pp son los puntos que llegan a la estructura, PT son el número de puntos del sistema de prueba). Sv se estima superponiendo una línea de prueba (LT) en las micrografías y contando las intersecciones de las líneas (I) con la membrana externa (om), la membrana interna (im) y las crestas (c), por lo tanto, Sv [om], Sv [im], Sv [c] (Sv = 2I / LT). A [m] se obtiene como la relación: A = Vv / 2NAT.
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Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura , Biologia CelularRESUMO
The objective of this work was to characterize the properties of a synthetic biomaterial composite with nanoparticles size (Blue Bone). This biomaterial is a composite recommended for dental and orthopedic grafting surgery, for guided bone regeneration, including maxillary sinus lift, fresh alveolus filling, and treatment of furcation lesions. The nano biomaterials surface area is from 30% to 50% higher than those with micro dimensions. Another advantage is that the alloplastic biomaterial has homogeneous properties due to the complete manufacturing control. The analyzed biomaterial composite was characterized by XRD, cytochemistry, scanning electron microscopy, porosimetry and in vivo experiments (animals). The results showed that the analyzed biomaterial composite has 78.76% hydroxyapatite [Ca5(PO4)3(OH)] with monoclinic structure, 21.03% ß-tricalcium phosphate [ß -Ca3(PO4)2] with trigonal structure and 0.19% of CaO with cubic structure, nanoparticles with homogeneous shapes, and nanoporosity. The in vivo experiments showed that the composite has null cytotoxicity, and the site of insertion biomaterials has a high level of vascularization and bone formation. The conclusion is that the synthetic biomaterial with Blue Bone designation presents characteristics suitable for use in grafting surgery applications.
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Materiais Biocompatíveis/química , Regeneração Óssea , Fosfatos de Cálcio/química , Durapatita/química , Nanopartículas/química , Animais , Substitutos Ósseos , Osso e Ossos , Microscopia Eletrônica de Varredura , Ortopedia , Porosidade , Período Pós-Operatório , Ratos , Ratos Wistar , Difração de Raios XRESUMO
The purpose of this work was to evaluate the physicochemical properties, the cytotoxicity and in vivo biocompatibility of MTA Repair HP (MTA HP) and White MTA (WMTA). The setting time, flow, radiopacity and water solubility were assessed. To the cytotoxicity assay, primary human osteoblast cells were exposed to several dilutions of both materials eluates. MTT assay, apoptosis assay and cell adhesion assay were performed. The in vivo biocompatibility was evaluated through histological analysis using different staining techniques. No differences were observed between MTA HP and WMTA for setting time, radiopacity, solubility and water absorption (P > 0.05). However, MTA HP showed a significantly higher flow when compared to WMTA (P < 0.05). Cell viability results revealed that the extracts of WMTA and MTA HP promoted the viability of osteoblasts. After incubation of cells with the endodontic cement extracts, the percentage of apoptotic or necrotic cells was very low (<3%). Furthermore, SEM results showed a high degree of cell proliferation and adhesion on both groups. MTA HP showed similar in vivo biocompatibility to the WMTA and the control group in all time-points. The MTA HP presented adequate physicochemical and biological properties with improved flow ability when compared to WMTA. Such improved flow ability may be a result of the addition of a plasticizing agent and should be related to an improvement in the handling of MTA HP.
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Compostos de Alumínio/química , Compostos de Alumínio/toxicidade , Compostos de Cálcio/química , Compostos de Cálcio/toxicidade , Óxidos/química , Óxidos/toxicidade , Materiais Restauradores do Canal Radicular/química , Materiais Restauradores do Canal Radicular/toxicidade , Silicatos/química , Silicatos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Combinação de Medicamentos , Humanos , Masculino , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Ratos , Ratos Wistar , Reologia , Solubilidade , Tela Subcutânea/efeitos dos fármacos , Tela Subcutânea/patologiaRESUMO
BACKGROUND: Diabetes mellitus patients (DM) have more severe progression of atherosclerotic disease than non-diabetic (NDM) individuals. In situ inflammation and oxidative stress are key points in the pathophysiology of atherosclerosis, a concept largely based on animal model research. There are few studies comparing inflammation and oxidative stress parameters in medium-sized arteries between DM and NDM patients. A fragment of the internal mammary artery used in coronary artery bypass grafting (CABG) will be employed for this purpose OBJECTIVE: To assess the expression of inflammatory markers tumor necrosis factor-α, transforming growth factor-ß1, nuclear factor kappa B, the enzymes superoxide dismutase, and catalase in the vascular wall of the arterial graft used in CABG, comparing DM and NDM patients RESULTS: The present study will add information to the vascular degenerative processes occurring in diabetic patients.
Assuntos
Ponte de Artéria Coronária , Doença da Artéria Coronariana/imunologia , Inflamação , Estresse Oxidativo , Adolescente , Adulto , Doença da Artéria Coronariana/fisiopatologia , Estudos Transversais , Complicações do Diabetes , Diabetes Mellitus , Humanos , Masculino , Projetos de PesquisaRESUMO
PURPOSE: Euterpe oleracea Mart. (açaí) seed extract (ASE), through its anti-hypertensive, antioxidant and anti-inflammatory properties, may be useful to treat or prevent human diseases. Several evidences suggest that oxidative stress and inflammation contribute to the pathogenesis of diabetic nephropathy; therefore, we tested the hypothesis that ASE (200 mg/kg-1day-1) prevents diabetes and hypertension-related oxidative stress and inflammation, attenuating renal injury. METHODS: Male rats with streptozotocin (STZ)-induced diabetes (D), and spontaneously hypertensive rats with STZ-induced diabetes (DH) were treated daily with tap water or ASE (D + ASE and DH + ASE, respectively) for 45 days. The control (C) and hypertensive (H) animals received water. RESULTS: The elevated serum levels of urea and creatinine in D and DH, and increased albumin excretion in HD were reduced by ASE. Total glomeruli number in D and DH, were increased by ASE that also reduced renal fibrosis in both groups by decreasing collagen IV and TGF-ß1 expression. ASE improved biomarkers of renal filtration barrier (podocin and nephrin) in D and DH groups and prevented the increased expression of caspase-3, IL-6, TNF-α and MCP-1 in both groups. ASE reduced oxidative damage markers (TBARS, carbonyl levels and 8-isoprostane) in D and DH associated with a decrease in Nox 4 and p47 subunit expression and increase in antioxidant enzyme activity in both groups (SOD, catalase and GPx). CONCLUSION: ASE substantially reduced renal injury and prevented renal dysfunction by reducing inflammation, oxidative stress and improving the renal filtration barrier, providing a nutritional resource for prevention of diabetic and hypertensive-related nephropathy.