Accumulation of damaged mitochondria in aging astrocytes due to mitophagy dysfunction: Implications for susceptibility to mitochondrial stress.

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.

Beneficial Effects of Capybara Oil Supplementation on Steatosis and Liver Apoptosis in Obese Mice.

Obesity is a complex chronic disease characterized by excess body fat (adipose) that is harmful to health and has been a major global health problem. It may be associated with several diseases, such as nonalcoholic fatty liver disease (NAFLD). Polyunsaturated fatty acids (PUFA) are lipid mediators that have anti-inflammatory characteristics and can be found in animals and plants, with capybara oil (CO) being a promising source. So, we intend to evaluate the hepatic pathophysiological alterations in C57Bl/6 mice with NAFLD, caused by obesity, and the possible beneficial effects of OC in the treatment of this disease. Eighteen 3-month-old male C57Bl/6 mice received a control or high-fat diet for 18 weeks. From the 15th to the 18th week, the animals received treatment-through orogastric gavage-with placebo or free capybara oil (5 g/kg). Parameters inherent to body mass, glucose tolerance, evaluation of liver enzymes, percentage of hepatic steatosis, oxidative stress, the process of cell death with the apoptotic biomarkers (Bax, Bcl2, and Cytochrome C), and the ultrastructure of hepatocytes were analyzed. Even though the treatment with CO was not able to disassemble the effects on the physiological parameters, it proved to be beneficial in reversing the morphological and ultrastructural damage present in the hepatocytes. Thus, demonstrating that CO has beneficial effects in reducing steatosis and the apoptotic pathway, it is a promising treatment for NAFLD.

Orphan GPCR GPRC5C Facilitates Angiotensin II-Induced Smooth Muscle Contraction.

BACKGROUND: GPCRs (G-protein-coupled receptors) play a central role in the regulation of smooth muscle cell (SMC) contractility, but the function of SMC-expressed orphan GPCR class C group 5 member C (GPRC5C) is unclear. The aim of this project is to define the role of GPRC5C in SMC in vitro and in vivo. METHODS: We studied the role of GPRC5C in the regulation of SMC contractility and differentiation in human and murine SMC in vitro, as well as in tamoxifen-inducible, SMC-specific GPRC5C knockout mice under basal conditions and in vascular disease in vivo. RESULTS: Mesenteric arteries from tamoxifen-inducible, SMC-specific GPRC5C knockout mice showed ex vivo significantly reduced angiotensin II (Ang II)-dependent calcium mobilization and contraction, whereas responses to other relaxant or contractile factors were normal. In vitro, the knockdown of GPRC5C in human aortic SMC resulted in diminished Ang II-dependent inositol phosphate production and lower myosin light chain phosphorylation. In line with this, tamoxifen-inducible, SMC-specific GPRC5C knockout mice showed reduced Ang II-induced arterial hypertension, and acute inactivation of GPRC5C was able to ameliorate established arterial hypertension. Mechanistically, we show that GPRC5C and the Ang II receptor AT1 dimerize, and knockdown of GPRC5C resulted in reduced binding of Ang II to AT1 receptors in HEK293 cells, human and murine SMC, and arteries from tamoxifen-inducible, SMC-specific GPRC5C knockout mice. CONCLUSIONS: Our data show that GPRC5C regulates Ang II-dependent vascular contraction by facilitating AT1 receptor-ligand binding and signaling.

The positioning mechanics of microtubule asters in Drosophila embryo explants.

Microtubule asters are essential in localizing the action of microtubules in processes including mitosis and organelle positioning. In large cells, such as the one-cell sea urchin embryo, aster dynamics are dominated by hydrodynamic pulling forces. However, in systems with more densely positioned nuclei such as the early Drosophila embryo, which packs around 6000 nuclei within the syncytium in a crystalline-like order, it is unclear what processes dominate aster dynamics. Here, we take advantage of a cell cycle regulation Drosophila mutant to generate embryos with multiple asters, independent from nuclei. We use an ex vivo assay to further simplify this biological system to explore the forces generated by and between asters. Through live imaging, drug and optical perturbations, and theoretical modeling, we demonstrate that these asters likely generate an effective pushing force over short distances.

Radioimmunotherapy as a pathogen-agnostic treatment method for opportunistic mucormycosis infections.

Invasive fungal infections (IFIs) such as mucormycosis are causing devastating morbidity and mortality in immunocompromised patients as anti-fungal agents do not work in the setting of a suppressed immune system. The coronavirus disease 2019 (COVID-19) pandemic has created a novel landscape for IFIs in post-pandemic patients, resulting from severe immune suppression caused by COVID-19 infection, comorbidities (diabetes, obesity) and immunosuppressive treatments such as steroids. The antigen-antibody interaction has been employed in radioimmunotherapy (RIT) to deliver lethal doses of ionizing radiation emitted by radionuclides to targeted cells and has demonstrated efficacy in several cancers. One of the advantages of RIT is its independence of the immune status of a host, which is crucial for immunosuppressed post-COVID-19 patients. In the present work we targeted the fungal pan-antigens 1,3-beta-glucan and melanin pigment, which are present in the majority of pathogenic fungi, with RIT, thus making such targeting pathogen-agnostic. We demonstrated in experimental murine mucormycosis in immunocompetent and immunocompromised mice that lutetium-177 (177Lu)-labelled antibodies to these two antigens effectively decreased the fungal burden in major organs, including the brain. These results are encouraging because they show the effectiveness of pathogen-agnostic RIT in significantly decreasing fungal burden in vivo, while they can also potentially be applied to treat the broad range of invasive fungal infections that express the pan-antigens 1,3-beta-glucan or melanin.

Liver structural injury in leptin-deficient (ob/ob) mice: lipogenesis, fibrogenesis, inflammation, and apoptosis / Lesión estructural del hígado en ratones con deficiencia de leptina (ob/ob): lipogénesis, fibrogénesis, inflamación y apoptosis

SUMMARY: Nonalcoholic fatty liver disease (NAFLD) might progress the steatosis to nonalcoholic steatohepatitis (NASH), reaching a cirrhosis state and possibly hepatocellular carcinoma. The liver of three-month-old C57BL/6J mice (wild-type, WT group, n=10) and leptin- deficient obese mice (ob/ob group, n=10) were studied, focusing on the mechanisms associated with the activation of the hepatic stellate cells (HSCs) and pro-fibrogenesis. The obese ob/ob animals' liver showed steatosis, increased lipogenesis gene expressions, inflammation, increased pro-inflammatory gene expressions, inflammatory infiltrate, and potential apoptosis linked to a high Caspase 3 expression. In ob/ob mice, liver sections were labeled in the fibrotic zones by anti-alpha-smooth muscle actin (alpha-SMA) and anti-Reelin, but not in the WT mice. Moreover, the alpha-SMA gene expression was higher in the ob/ob group's liver than the WT group. The pro-fibrogenic gene expressions were parallel to anti- alpha-SMA and anti-Reelin immunofluorescence, suggesting HSCs activation. In the ob/ob animals, there were increased gene expressions involved with lipogenesis (Peroxisome proliferator-activated receptor-gamma, Cell death-inducing DFFA-like effector-c, Sterol regulatory element-binding protein-1c, and Fatty acid synthase), pro-fibrogenesis (Transforming growth factor beta1, Smad proteins- 3, Yes-associated protein-1, Protein platelet-derived growth factor receptor beta), pro-inflammation (Tumor necrosis factor-alpha, and Interleukin-6), and apoptosis (Caspase 3). In conclusion, the results in obese ob/ob animals provide a clue to the events in humans. In a translational view, controlling these targets can help mitigate the hepatic effects of human obesity and NAFLD progression to NASH.

RESUMEN: La enfermedad del hígado graso no alcohólico (HGNA) puede progresar de la esteatosis a esteatohepatitis no alcohólica (ENA), alcanzando un estado de cirrosis y posiblemente carcinoma hepatocelular. Se estudió el hígado de ratones C57BL / 6J de tres meses de edad (tipo salvaje, grupo WT, n = 10) y ratones obesos con deficiencia de leptina (grupo ob/ob, n = 10), centrándose en los mecanismos asociados con la activación de las células estrelladas hepáticas (HSC) y profibrogénesis. El hígado de los animales obesos ob/ob mostró esteatosis, aumento de la expresión génica de la lipogénesis, inflamación, aumento de la expresión génica proinflamatoria, infiltrado inflamatorio y posible apoptosis ligada a una alta expresión de Caspasa 3. En ratones ob/ob, las sec- ciones de hígado se marcaron en las zonas fibróticas con anti-alfa- actina de músculo liso (alfa-SMA) y anti-Reelin, pero no en los ratones WT. Además, la expresión del gen alfa-SMA fue mayor en el hígado del grupo ob/ob que en el grupo WT. Las expresiones génicas profibrogénicas fueron paralelas a la inmunofluorescencia anti-alfa-SMA y anti-Reelin, lo que sugiere la activación de las HSC. En los animales ob/ob, hubo un aumento de las expresiones génicas involucradas con la lipogénesis (receptor activado por proliferador de peroxisoma gamma, efector c similar a DFFA inductor de muerte celular, proteína de unión al elemento regulador de esterol-1c y sintasa de ácidos grasos), pro-fibrogénesis (factor de crecimiento transformante beta 1, proteínas Smad-3, proteína-1 asociada a Yes, receptor beta del factor de crecimiento derivado de plaquetas de proteínas), proinflamación (factor de necrosis tumoral alfa e interleucina-6) y apoptosis (caspasa 3). ). En conclusión, los resultados en animales obesos ob/ob proporcionan una pista de los eventos en humanos. Desde un punto de vista traslacional, el control de estos objetivos puede ayudar a mitigar los efectos hepáticos de la obesidad humana y la progresión de HGNA a ENA.

Resección Tubular Microquirúrgica de un Subependimoma Extenso del Ventrículo Lateral Izquierdo: Video Operatorio en 2D / Microsurgical Tubular Resection of an Extensive Subependymoma of the Left Lateral Ventricle: Operative Video in 2D

Introducción: Los subependimomas intracraneales son raros, representan el 0.2-0.7% de todos los tumores del sistema nervioso central1,2 y se originan en los ventrículos laterales en el 30-40% de los casos.3 Los síntomas usualmente se asocian a hipertensión endocraneana secundaria a hidrocefalia obstructiva.4 La resección completa del tumor es curativa en esta patología.5 El abordaje trans-surcal es seguro para lesiones ventriculares profundas y el uso de los retractores tubulares minimizan la retracción del parénquima cerebral evitando la compresión directa con valvas. Esto permite disminuir la presión del tejido cerebral que puede ocluir los vasos y producir isquemia local generando una lesión neurológica permanente. Descripción del caso: Se presenta el caso de una paciente de 66 años, diestra, con cefalea crónica que aumenta en frecuencia en el último mes. La resonancia cerebral contrastada muestra un tumor extenso en el ventrículo lateral izquierdo con signos de hidrocefalia obstructiva. Intervención: Se coloca la paciente en posición supina. Se hace una incisión bicoronal y se hace un abordaje trans-surcal F1/F2 izquierdo. Se coloca un retractor tubular guiado con el puntero de neuronavegación, introduciéndolo directamente en el parénquima cerebral y fijándolo al soporte de Leyla. Se colocó un catéter de ventriculostomía contralateral y se retira a las 48 horas sin complicaciones asociadas. La resonancia contrastada postoperatoria demuestra una resección completa del tumor. El análisis de patología reveló un subependimoma grado I de la clasificación de la Organización Mundial de la Salud. La paciente presentó transitoriamente apatía y pérdida del control del esfínter urinario que resolvieron completamente a las 3 semanas después de la cirugía. Se firmó un consentimiento firmado para la publicación de la información utilizada en este trabajo. Conclusión: La resección completa microscópica de un subependimoma extenso del ventrículo lateral izquierdo es factible a través de un abordaje tubular transulcal.

Introduction: Intracranial subependymomas are rare, representing only 0.2-0.7% of all central nervous system tumors1,2 and arise in the lateral ventricles in 30-40% of the cases.3 Symptoms depend on tumor location and usually arise when the cerebrospinal fluid (CSF) is blocked, generating a consequent intracranial hypertension.4 Microsurgical gross-total resection is possible and curative for these tumors.5 The transcortical/trans-sulcal approach is a safe approach for the access of deep-seated intraventricular lesions. The use of tubular retractor systems minimizes retraction injury when passing through the cortex and deep white matter tracts. This allows a decrease in the pressure on brain tissue that can occlude the brain vessels and produce local ischemia and a consequent permanent neurological injury. Case description: This is a case of a 66-year-old woman who presented chronic headaches that increased in frequency in the last month. Enhanced-brain MRI demonstrated a large left ventricular lesion with signs of obstructive hydrocephalus. Procedure: Patient was positioned supine. A bicoronal incision was used to perform a left frontal craniotomy. An F1/F2 transcortical/trans-sulcal approach was used. A guided tubular retractor is placed with the neuronavigation pointer, inserting it directly into the brain parenchyma and fixing it to the Leyla support. Postoperative postcontrast MRI demonstrated a complete resection of the tumor. Histopathological analysis revealed a subependymoma (World Health Organization Grade I). The patient presented transient apathy and loss of urinary sphincter control that completely resolved 3 weeks after surgery. Written informed consent was obtained for publication of information used for this work. Conclusions: A complete microsurgical resection of a large left ventricular subependymoma is feasible through a trans-sulcal tubular approach.

Hepatic mitochondria in diet-induced obese mice (stereology and molecular analysis) / Mitocondrias hepáticas en ratones obesos inducidos por la dieta (estereología y análisis molecular)

SUMMARY: The world population is going through an obesity epidemic that has severe consequences for the health system. This study focused on studying hepatic mitochondria in obese animals induced by a high-fat (HF) diet and used the model-based stereology in electron micrographs for the quantitative study. Besides, the gene expressions of molecular markers of mitochondrial biogenesis carnitine palmitoyltransferase 1a (Cpt 1α), mitochondrial transcription factor a (Tfam), uncoupling protein 3 (Ucp 3), and nuclear respiratory factor 1 (Nrf 1) were analyzed. The HF diet caused a weight gain of +1820 % comparing the control group (C) with the HF group (from 0.32±0.31 g to 5.5±0.39 g, P<0.001). The HF group showed fat droplets in the hepatocyte cytoplasm (steatosis) and less dense and large mitochondria in transmission electron microscopy. The mitochondria size (cross-section) did not show a significant difference between the groups C and HF. However, the mitochondria numerical density per area was 30 % less, the mitochondrial surface density (outer membrane) was 20 % less, and the mitochondrial volume density was 22 % less in the HF group than the C group. The gene expressions of molecular markers of mitochondrial biogenesis Cpt 1α, Tfam, Ucp 3, and Nrf 1 decreased in the HF group compared to the C group. The quantitative results match perfectly with the molecular ones of mitochondrial biogenesis markers. In the future, it will be crucial to verify if and how these data recover with the reduction of obesity, which would be of significant interest given the current obesity epidemic that affects the world population.

RESUMEN: La población mundial atraviesa una epidemia de obesidad que tiene graves consecuencias para el sistema de salud. Este estudio se centró en el análisis de las mitocondrias hepáticas en animales obesos inducidos por una dieta alta en grasas (HF) y utilizó la estereología basada en modelos en micrografías electrónicas para el estudio cuantitativo. Además, se analizaron las expresiones génicas de los marcadores moleculares de la biogénesis mitocondrial carnitina palmitoiltransferasa 1a (Cpt 1α), factor de transcripción mitocondrial a (Tfam), proteína desacoplante 3 (Ucp 3) y factor respiratorio nuclear 1 (Nrf 1). La dieta HF provocó un aumento de peso de +1820 % comparando el grupo de control (C) con el grupo HF (de 0,32 ± 0,31 g a 5,5 ± 0,39 g, P <0,001). El grupo HF mostró gotas de grasa en el citoplasma de los hepatocitos (esteatosis) y mitocondrias menos densas y grandes en la microscopía electrónica de transmisión. El tamaño de las mitocondrias (sección transversal) no mostró una diferencia significativa entre los grupos C y HF. Sin embargo, la densidad numérica de mitocondrias por área fue 30% menor, la densidad de superficie mitocondrial (membrana externa) fue 20 % menor y la densidad de volumen mitocondrial fue 22 % menor en el grupo HF que en el grupo C. Las expresiones génicas de los marcadores moleculares de la biogénesis mitocondrial Cpt 1α, Tfam, Ucp 3 y Nrf 1 disminuyeron en el grupo HF en comparación con el grupo C. Los resultados cuantitativos coinciden perfectamente con los moleculares de los marcadores de biogénesis mitocondrial. En el futuro, será crucial verificar si estos datos se recuperan y cómo se recuperan con la reducción de la obesidad, lo que sería de gran interés dada la actual epidemia de obesidad que afecta a la población mundial.

Obstrução gástrica por bezoar / Gastric obstruction due to bezoar

A obstrução por bezoar é um acúmulo de material parcialmente ou não digerido no estômago. Bezoares gástricos são raros e ocorrem com mais frequência em pacientes com transtornos de comportamento, esvaziamento gástrico anormal ou após cirurgia gástrica. Podem ser assintomáticos ou apresentar sintomas como dor abdominal e vômitos incoercíveis. Podem ainda ter composições diversas e ocorrer em todas as faixas etárias. O objetivo deste relato foi demonstrar um caso de bezoar gástrico em paciente previamente submetido à cirurgia bariátrica e internado com quadro de vômitos incoercíveis e hemorragia digestiva alta, com a demonstração de que sua resolução completa ocorreu na realização da segunda endoscopia.

Bezoar obstruction is an accumulation of partially digested or undigested material in the stomach. Gastric bezoars are rare and occur more frequently in patients with behavioral disorders, abnormal gastric emptying, or after gastric surgery. They may be asymptomatic or present with symptoms such as abdominal pain and incoercible vomiting. They can have diverse compositions and occur in all age groups. The aim of this report was to demonstrate a case of gastric bezoar in a patient who previously underwent a bariatric surgery and was hospitalized with incoercible vomiting and upper gastrointestinal hemorrhage, with the demonstration that its complete resolution occurred during the second endoscopy.

Commentary on mitochondrial stereology in transmission electron microscopy / Comentario sobre estereología mitocondrial en microscopía electrónica de transmisión

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.

Influence of duodenogastric reflux in the gastric mucosa histological changes of rats infected with Helicobacter pylori / Influência do refluxo duodenogástrico nas alterações histológicas da mucosa gástrica de ratos infectados com Helicobacter pylori

ABSTRACT Objective: to evaluate the influence of Duodenal reflux in histological changes of the gastric mucosa of rats infected with Helicobacter pylori submitted to pyloroplasty. Methods: after two weeks of acclimation, we infected 30 male Wistar rats with Helicobacter pylori. We randomly divided them into three groups: one submitted to pyloroplasty, another to partial gastrectomy and the third, only infected, was not operated. After six months of surgery, euthanasia was carried out. Gastric fragments were studied by light microscopy to count the number of H. pylori, and to observe the histological changes (gastritis, metaplasia, dysplasia and neoplasia). We confirmed these changes by immunohistochemistry using the molecular markers PCNA and TGF-beta. Results: the animals submitted to pyloroplasty had higher percentage of colonization by H. pylori (median=58.5; gastrectomy=16.5; control=14.5). There was a positive correlation between the amount of H. pylori and the occurrence of chronic gastritis present in the antral fragments. Neoplasia occurred in 40% of rats from the group submitted to pyloroplasty. The staining with PCNA and TGF-ß confirmed the histopathological changes visualized by optical microscopy. Conclusions: the antral region was the one with the highest concentration of H. pylori, regardless of the group. There was a positive correlation between the appearance of benign disorders (chronic gastritis, metaplasia, dysplasia) and cancer in mice infected with H. pylori submitted to pyloroplasty.

RESUMO Objetivo: avaliar a influência do refluxo duodenogástrico nas alterações histológicas da mucosa gástrica de ratos, infectados por Helicobacter pylori, submetidos à piloroplastia. Método: após duas semanas de aclimatação, 30 ratos machos da raça Wistar, foram infectados com o microorganismo patogênico H. pylori. De forma aleatória, foram divididos em três grupos: um submetido à piloroplastia, outro à gastrectomia parcial e o terceiro, apenas infectados, não foi operado. Após seis meses de operados, procedeu-se a eutanásia. Os fragmentos gástricos foram estudados por microscopia óptica, para a contagem da quantidade de H. pylori, e para a observação das alterações histológicas (gastrite, metaplasia, displasia e neoplasia). A confirmação dessas alterações foi feita por imuno-histoquímica, utilizando os marcadores moleculares PCNA e TGFbeta. Resultados: os animais submetidos à piloroplastia tiveram maior percentual de colonização por H. pylori (mediana=58,5; gastrectomia=16,5; controle=14,5). Houve correlação positiva entre quantidade de H. pylori e ocorrência de gastrite crônica presente nos fragmentos do antro. Ocorreu 40% de neoplasia no grupo submetido à piloroplastia. A marcação de PCNA e TGF-beta confirmou as alterações histopatológicas visibilizadas à microscopia óptica. Conclusões: a região do antro foi a que apresentou a maior concentração de H. pylori, independente do grupo. Houve correlação positiva entre e o aparecimento de alterações benignas (gastrite crônica, metaplasia, displasia), e de neoplasia nos ratos infectados com H. pylori submetidos à piloroplastia.

Peripheral blood fibrocytes: new information to explain the dynamics of Leishmania infection

Fibrocytes are important for understanding the progression of many diseases because they are present in areas where pathogenic lesions are generated. However, the morphology of fibrocytes and their interactions with parasites are poorly understood. In this study, we examined the morphology of peripheral blood fibrocytes and their interactions with Leishmania (L.) amazonensis . Through ultrastructural analysis, we describe the details of fibrocyte morphology and how fibrocytes rapidly internalise Leishmania promastigotes. The parasites differentiated into amastigotes after 2 h in phagolysosomes and the infection was completely resolved after 72 h. Early in the infection, we found increased nitric oxide production and large lysosomes with electron-dense material. These factors may regulate the proliferation and death of the parasites. Because fibrocytes are present at the infection site and are directly involved in developing cutaneous leishmaniasis, they are targets for effective, non-toxic cell-based therapies that control and treat leishmaniasis.

Therapeutic dose of Ginkgo biloba extract 761 may alter the urine excretion of Wistar rats

Wistar rats (n=20) were divided in two groups: G1 received 2 mg/kg of GBE (Ginkgo biloba extract 761), whereas G2 received the same volume of a sodium chloride solution (0.9%), both for 10 days. After a 7-day interval, the treatment was repeated for 8 days. Urine volume and food and water intake were measured daily during this protocol. Histological assessments were performed. No significant difference (p>0.05) was observed in food and water intake of animals during treatment with GBE. Animals who received GBE had a smaller urine volume and increase of weight with a significance difference (p<0.05) during the first and second exposure period. No histological alteration was observed in tissues, except for the kidney of the experimental group, which revealed a higher concentration of red cells in the glomerulus with a strong staining for Vascular Endothelial Growth Factor (VEGF). The introduction of GBE (therapeutic dose) in health rats may promote alterations in the physiology of the kidney, but no sufficient to modify the glomerulus architecture, including at ultra structural level (electron microscopy).

Identification of skin phototypes through in vivo photoacoustic measurements / Identificação dos fototipos de pele através de medidas fotoacústicas in vivo

The aim of the present work was to classify and identify skin phototypes through in vivo photoacoustic (PA) measurements. Fifty-seven female volunteers took part in the study, being clinically evaluated and classified according to skin phototype (Fitzpatrick classification). After cleaning the skin area to be measured, the PA signal level was obtained for the inner and outer faces of both forearms. Volunteers were then classified according to the respective PA signal amplitude; subsequently, this classification was compared to the phototype classification and to the recently proposed Baumann classification. Comparison between the PA signal of the inner and outer faces of the forearm shows a highly significant statistical difference (p < 0.005), attributed to the higher pigmentation level of the skin region continuously exposed to solar radiation, demonstrating that skin constitution and aspect are influenced by the level of sun exposure. Comparison among phototypes was performed separately for the inner and outer faces of the forearm. The results show that the PA signal level (amplitude) for the inner forearm tends to scale with skin phototype, also allowing the division of the volunteers in two groups, according to their pigmentation levels and also following the recent Baumann classification. In this way, the photoacoustic methodology presented allows an objective, numerical classification of the skin types.

O objetivo do presente trabalho foi de identificar e classificar os fototipos de pele através de mensurações fotoacústicas (PA) utilizada para caracterizar a pele em função da amplitude do sinal observado in vivo. Participaram do estudo cinquenta e sete mulheres voluntárias que incialmente foram avaliadas e classificadas de acordo com o fototipo da pele (classificação de Fritzpatrick). Foram realizadas medidas nas regiões interna e externa de ambos os antebraços, após a limpeza do mesmo com álcool 70%. As voluntárias foram classificadas de acordo com o sinal fotoacústico, em seguida comparados com a classificação proposta recentemente por Baumann. A comparação entre o sinal PA das faces interna e externa do antebraço mostra uma diferença altamente significativa (p < 0,005), atribuída ao maior nível de pigmentação da pele da região continuamente expostos à radiação solar, demonstrando que a constituição do aspecto da pele é influenciada pelo nível de exposição ao sol. A comparação entre os fototipos foi realizada separadamente para as faces interna e externa do antebraço. Os resultados mostram que o nível (amplitude) do sinal PA para a parte interna do antebraço tende a seguir a classificação em fototipos, permitindo também a divisão de voluntários em dois grupos, conforme o nível de pigmentação, seguindo assim a classificação recentemente proposta por Baumann. Assim, a metodologia fotoacústica apresentada permite uma classificação objetiva, numérica, dos tipos de pele.

The microfibril-elastin fiber system distribution in left atrioventricular valve of the rat / Distribución del sistema de microfibrillas y fibras de elastina en la valva atrioventricular izquierda de la rata

The microfibril-elastin fiber system, an important constituent of the extracellular matrix, was studied in the rat left atrioventricular valve to investigate the interrelationship of oxytalan, elaunin and elastic fibers in left atrioventricular valve morphology. The elastin fibers forms continuous bundles observed along the length of the valve in atrial and ventricular layers and oriented parallel to endothelium. The elaunin and oxytalan fibers are distributed in the thickest fiber bundles along the length of the valve. The thinner fibers which radiated towards both the atrial and spongiosa layers, either as isolated or arborescent fiber bundles were identified as oxytalan fibers. With transmission electron microscopy elastic fibers were seen mainly in the atrial layer. The spongiosa layer was composed of elaunin and oxytalan fibers and ventricular layer showed elaunin fibers arranged in continuous bundles parallel to the endothelium. Both fibrillin and elastin were seen and identified by immunocytochemistry with colloidal gold in the left atrioventricular valve spongiosa and atrial layers. These observations allow us to suggest that the microfibril-elastin fiber system plays a role in the mechanical protection and maintenance of the integrity of the rat left atrioventricular valve.

Fue estudiado el sistema de fibras microfibrillas-elastina, un componente importante de la matriz extracelular, en la valva atrioventricular izquierda de rata, con la finalidad de investigar la interrelación de oxitalán, elaunin y fibras elásticas en la morfología de dicha valva. Las fibras de elastina forman paquetes continuos a lo largo de la valva en las capas atriales y ventriculares, orientadas paralelamente al endotelio. Las fibras de elaunin y oxitalán se distribuyen en haces de fibras más gruesas a lo largo de la valva. Las fibras más delgadas, las cuales se irradiaban hacia las capas atrial y esponjosa, ya sea como haces de fibras aisladas o arborescentes, fueron identificadas como fibras oxitalán. En la capa atrial a través de microscopía electrónica de transmisión se observaron principalmente fibras elásticas. La capa esponjosa estaba compuesta por fibras de elaunin y oxitalán; la capa ventricular mostró fibras de elaunin dispuestas en haces continuos paralelos al endotelio. Tanto fibrilina y elastina se observaron e identificaron por inmunocitoquímica con oro coloidal en las capas esponjosa y atrial de la valva atrioventricular izquierda. Estas observaciones nos permiten sugerir que el sistema de fibras de elastina-microfibrillas tienen participación en la protección mecánica y la mantención de la integridad de la valva atrioventricular izquierda en la rata.

Low-Intensity physical activity beneficially alters the ultrastructural renal morphology of spontaneously hypertensive rats

INTRODUCTION AND OBJECTIVE: Kidney disorders can cause essential hypertension, which can subsequently cause renal disease. High blood pressure is also common among those with chronic kidney disease; moreover, it is a well-known risk factor for a more rapid progression to kidney failure. Because hypertension and kidney function are closely linked, the present study aimed to observe the beneficial effects of low-intensity physical activity on structural and ultrastructural renal morphology and blood pressure in normotensive and spontaneously hypertensive rats. METHOD: Male Wistar-Kyoto rats and spontaneously hypertensive rats were randomly allocated into four groups: sedentary or exercised Wistar-Kyoto and sedentary or exercised spontaneously hypertensive rats. The exercise lasted 20 weeks and consisted of treadmill training for 1 hour/day, 5 days/week. RESULTS: The exercised, spontaneously hypertensive rats showed a significant blood pressure reduction of 26 percent. The body masses of the Wistar-Kyoto and spontaneously hypertensive strains were significantly different. There were improvements in some of the renal structures of the animals treated with physical activity: (i) the interdigitations of the proximal and distal convoluted tubules; (ii) the basal membrane of the proximal and distal convoluted tubules; and (iii) in the basal membrane, slit diaphragm and pedicels of the glomerular filtration barrier. The spontaneously hypertensive rats also showed a decreased expression of connexin-43. CONCLUSION: Physical exercise could be a therapeutic tool for improving kidney ultrastructure and, consequently, renal function in hypertensive individuals.

Vimentin and laminin are altered on cheek pouch microvessels of streptozotocin-induced diabetic hamsters

OBJECTIVE: Normal endothelial cells respond to shear stress by elongating and aligning in the direction of fluid flow. Hyperglycemia impairs this response and contributes to microvascular complications, which result in deleterious effects to the endothelium. This work aimed to evaluate cheek pouch microvessel morphological characteristics, reactivity, permeability, and expression of cytoskeleton and extracellular matrix components in hamsters after the induction of diabetes with streptozotocin. METHODS: Syrian golden hamsters (90-130 g) were injected with streptozotocin (50 mg/kg, i.p.) or vehicle either 6 (the diabetes mellitus 6 group) or 15 (the diabetes mellitus 15 group) days before the experiment. Vascular dimensions and density per area of vessels were determined by morphometric and stereological measurements. Changes in blood flow were measured in response to acetylcholine, and plasma extravasation was measured by the number of leakage sites. Actin, talin, α-smooth muscle actin, vimentin, type IV collagen, and laminin were detected by immunohistochemistry and assessed through a semiquantitative scoring system. RESULTS: There were no major alterations in the lumen, wall diameters, or densities of the examined vessels. Likewise, vascular reactivity and permeability were not altered by diabetes. The arterioles demonstrated increased immunoreactivity to vimentin and laminin in the diabetes mellitus 6 and diabetes mellitus 15 groups. DISCUSSION: Antibodies against laminin and vimentin inhibit branching morphogenesis in vitro. Therefore, laminin and vimentin participating in the structure of the focal adhesion may play a role in angiogenesis. CONCLUSIONS: Our results indicated the existence of changes related to cell-matrix interactions, which may contribute to the pathological remodeling that was already underway one week after induction of experimental diabetes.

Uncaria tomentosa extract: evaluation of effects on the in vitro and in vivo labeling of blood constituents with technetium-99m

The influence (in vivo and in vitro) of an Uncaria tomentosa extract (Cats claw) on the labeling of red blood cells (RBCs) and plasma and cellular proteins with technetium-99m (Tc-99m) was evaluated. For the in vivo treatment, animals were treated with Cats claw. For the in vitro treatment, heparinized blood was incubated with Cats claw before the addition of stannous chloride (SnCl2) and Tc-99m. Samples of plasma (P) and RBCs were separated and also precipitated with trichloroacetic acid. The soluble and insoluble fractions of P and RBCs were isolated. The analysis of the results of the in vivo study, indicates that there is no significant alteration on the uptake of Tc-99m by the blood constituents, but it significantly decrease (p<0.05) the labeling of blood constituents by in vitro methods. These effects could be due to chelation of stannous and /or pertechnetate ions and blockage of the Tc-99m bindings sites.

O objetivo do presente estudo foi avaliar a influência (in vivo e in vitro) de um extrato de Uncaria tomentosa (unha de gato) na marcação de hemácias e proteínas plasmáticas e celulares com tecnécio-99m (Tc-99m). Para o estudo in vivo, animais foram tratados com um extrato de unha de gato. Para o estudo in vitro, sangue heparinizado foi incubado com o extrato de unha de gato antes da adição de cloreto estanoso (SnCl2) e Tc-99m. Amostras de plasma e células foram separadas e também precipitadas com ácido tricloracético. As frações solúveis e insolúveis foram isoladas. A análise dos resultados do estudo in vivo, indica que não houve alteração significante na captação de Tc-99m pelos constituintes sanguíneos, entretanto, no tratamento in vitro, ocorreu redução significante da marcação de constituintes sanguíneos. Esses efeitos poderiam ser justificados por quelação dos íons estanoso e pertecnetato e bloqueio dos sítios de ligação do Tc-99m.

Experimental models using radionuclides for assessment of the effects of natural drugs

The aim of this study was to evaluate the effect of the extracts of Nectandra membranacea (N. membranacea), Ginkgo biloba (EGb) and Passiflora (PEF) on the morphology of red blood cells (RBC), on the biodistribution of sodium pertechnetate (99mTcO4Na), on the morphology of duodenum and on the labeling of blood constituents (BC, IF-P, IF-BC) with technetium-99m (Tc-99m). Morphometry studies also were performed. The results show that EGb promotes alteration of the labeling of BC, IF-P and IF-BC (p<0.05). The N. membranacea extract does not promote significant alteration of the radiolabeling, and PEF extract alters the IF-P labeling. N. membranacea, EGb and PEF extracts were able to alter the RBC morphology (P<0.05). N. membranacea extract and EGb modifies the biodistribution of the 99mTcO4Na, and EGb influences the morphometry of duodenum isolated from rats (P<0.05).

O objetivo deste estudo foi avaliar o efeito de um extrato de Nectandra (N. membranacea), de Ginkgo (EGb) e de Passiflora e. flavicarpa (PEF) na marcação de constituintes sanguíneos (BC, IF-P, IF-BC) com Tc-99m, na morfologia de hemácias (RBC), na biodistribuição do 99mTcO4Na na morfologia do duodeno. Amostras de sangue foram incubadas com os extratos. Tc-99m foi adicionado e as frações do plasma (IF-P) e da célula (IF-BC) foram isoladas. Estudos morfométricos foram realizados. Os resultados mostram que EGb promove alteração na marcação de BC, IF-P e IF-BC. N. membranacea não altera a radiomarcação e PEF altera a marcação de IF-P. O extrato de N. membranacea, EGb e PEF alteraram a morfologia de RBC (p<0.05). Os extratos de N. membranacea e EGb modificam a biodistribuição do 99mTcO4Na, e o EGb influencia a morfometria (p<0.05) do duodeno de ratos.

Ultrastructural analysis of kidney, liver and duodenum isolated from treated rats with Ginkgo Biloba extract and effects of this medicinal plant on the biodistribution of the padiopharmaceutical sodium pertechnetate

Ginkgo biloba extract (EGb) has been used to treat memory and concentration deficits, acts as platelet activatingfactor antagonism and prevents against damages caused by free radicals. EGb is a standardized extract that contains 24% flavonoids and 6% terpenoids. The aim of this work was to evaluate the possible influence of an EGb on the ultrastructure of some organs isolated from rats and on the biodistribution of sodium pertechnetate (99mTcO4Na). The animals were treated with EGb and after six days, received 99mTcO4Na. The organs were isolated and fixed for ultrastructural analysis. The results showed that EGb has modified the ultrastructure of kidney, liver and duodenum and altered the biodistribution of 99mTcO4Na (P<0.05). It is speculated that the substances present in the EGb could act directly or generate metabolites capable to promote changes on the biodistribution of 99mTcO4Na and on the morphology of organs at ultrastructural level.

O extrato de Ginkgo Biloba extract (EGb) tem sido usado para tratar dificuldades de concentração,memória, age como antagonista do fator de ativação de plaquetas e previne contra danos causados por radicais livres. EGb é um extrato padronizado com 24% de flavonóides e 6% de lactonas terpênicas. O objetivo deste estudo foi avaliar o efeito de um EGb na ultraestrutura de alguns órgãos isolados de ratos e na biodistribuição do radiofármaco pertecnetato de sódio (99mTcO4Na). Os animais foram tratados com EGb e após 6 dias receberam 99mTcO4Na. Os órgãos foram isolados e a radioatividadedeterminada. Os tecidos foram fixados para microscopia eletrônica. Os resultados mostraram que EGb alterou a ultraestrutura do rim, figado e duodeno e modificou a biodistribuição do99mTcO4Na. Sugerimos que substâncias presentes no EGb poderiam agir diretamente ou gerar metabólitos capazes de promover alterações nabiodistribuição e na morfologia de órgãos em nível ultraestrutural.