Addition of insulin-like growth factors (IGF-1) for the regeneration of critical defects in peripheral nerve injuries. Biological findings

Producción CientíficaThe purpose is analyze the biological and cellular regeneration of non-repairable lesions of peripheral nerve by muscle graft enhanced with growth factors. Methods: Controlled clinical experimental trial, level I evidence. Critical peripheral nerve injuries repair through acellular muscle graft alone versus its enrichment with IGF-1 (10 mg/ml mecasermin). Clinical and functional control for 3 months. Animals were sacrificed at 90-100 days, obtaining samples for macro and microscopy with blue toluidine staining, hematoxylin-eosin and Masson trichrome. Results: Regenerating axons can pass through a defect length of 15 mm with the addition of an acellular skeletal muscle graft and repopulate the distal nerve. Basal lamina tubes, acting as matrices for the axonal growth, appears that sensory recovery exceeds the rate of motor nerve fibers growth. Finding a number of regenerating axons greater than healthy sciatic, ensures the functional connection of distal axons to their target innervation. In contrast, grafts myelinated fibers are smaller than those of healthy sciatic nerve. Discussion: Acellular muscle fibers basal lamina define tubes that could support axonal regeneration, acting as matrices for the growth of axons, when grafted into a nerve defect. Stereologic studies biological sections to quantify the increase in the total number of axons, the density thereof and the thickness of the myelin from microscopic examination of histological slices of animals treated with the growth factor IGF-1

Pathological and therapeutic approach to endotoxin-secreting bacteria involved in periodontal disease

Producción CientíficaIt is widely recognized that periodontal disease is an inflammatory entity of infectious origin, in which the immune activation of the host leads to the destruction of the supporting tissues of the tooth. Periodontal pathogenic bacteria like Porphyromonas gingivalis, that belongs to the complex net of oral microflora, exhibits a toxicogenic potential by releasing endotoxins, which are the lipopolysaccharide component (LPS) available in the outer cell wall of Gram-negative bacteria. Endotoxins are released into the tissues causing damage after the cell is lysed. There are three well-defined regions in the LPS: one of them, the lipid A, has a lipidic nature, and the other two, the Core and the O-antigen, have a glycosidic nature, all of them with independent and synergistic functions. Lipid A is the “bioactive center” of LPS, responsible for its toxicity, and shows great variability along bacteria. In general, endotoxins have specific receptors at the cells, causing a wide immunoinflammatory response by inducing the release of pro-inflammatory cytokines and the production of matrix metalloproteinases. This response is not coordinated, favoring the dissemination of LPS through blood vessels, as well as binding mainly to Toll-like receptor 4 (TLR4) expressed in the host cells, leading to the destruction of the tissues and the detrimental effect in some systemic pathologies. Lipid A can also act as a TLRs antagonist eliciting immune deregulation. Although bacterial endotoxins have been extensively studied clinically and in a laboratory, their effects on the oral cavity and particularly on periodontium deserve special attention since they affect the connective tissue that supports the tooth, and can be linked to advanced medical conditions. This review addresses the distribution of endotoxins associated with periodontal pathogenic bacteria and its relationship with systemic diseases, as well as the effect of some therapeutic alternatives

in vivo toxicity of the ribosome-inactivating lectin ebulin f in elderly mice

Producción CientíficaEbulin f is a ribosome-inactivating protein (RIP) present in green fruits of the dwarf elder (Sambucus ebulus L). Since dwarf elder fruits are used for food and as a medicine, we assessed the study of toxicological effects and safety of ebulin f in elderly mice, comparing these results with those reported in young animals and with other RIPs. Female Swiss mice aged 6 and 12 months of age were intraperitoneally injected with a single dose from 1.4 to 4.5 mg/kg ebulin f. Heart, stomach, intestines, lung, kidney, liver, spleen, pancreas, adrenal gland, uterus, ovary and brain were studied. Histology analysis was carried out by staining with hematoxylin and eosin and Masson's trichrome observed with a light microscope, or apoptosis detection by TUNEL method observed with a confocal laser microscope. Treated animals injected with the lower dose could recover their weights, but after 14 days half of them died. The higher dose caused a progressive loss of body weight leading to death. In the animals of the experimental groups it was found atrophy of Lieberkühn's crypts, pneumonia, nephronal degeneration, myocardial atrophy, centrolobular hepatic necrosis, splenic white pulp necrosis foci and increased rate of apoptosis in the intestines and liver, in which apoptoses were mainly located in the vicinity of the lobular central vein. We conclude that ebulin f affects vital organs in elderly mice.UVa-GIR Inmunotoxinas AntitumoralesUCM-CAM Research group 95024

Unexpected toxicity of green tea polyphenols in combination with the Sambucus RIL ebulin

Producción CientíficaThe safety of concentrated food complements intake is a major health concern. It has been well established that green tea polyphenols (GTPs) consumption promotes healthy effects. However, the ingestion of large amounts of GTPs is a matter of controversy due to reported adverse effects. We underwent a preliminary exploration of the effects of the oral administration of a standardized concentrated GTPs preparation on mice which suffered from reversible intestinal derangement promoted by sublethal amounts of the antiribosomal lectin ebulin f from dwarf elder (Sambucus ebulus L.). Neither independent oral administration of 30 mg/kg body weight Polyphenon 60 nor intraperitoneal administration of 2.5 mg/kg body weight ebulin f triggered lethal toxicity. In contrast, the simultaneous administration of these same doses of both Polyphenon 60 and ebulin f triggered an important and unexpected synergistic toxic action featured by the biphasic reduction of weight, which continued after eight days, reaching a reduction of 40%. Lethality appeared 2 days after the onset of the combined treatment and reached more than 50% after 10 days.Junta de Castilla y León y Consejería de Sanidad (GR106

Infrared spectroscopic analysis of the inorganic components from teeth exposed to psychotherapeutic drugs

Teeth are unique and complex anatomical organs that can provide relevant data about a person's health, and play an important role in forensic medicine. Teeth are exposed to food, drinks, and the microbiota of the oral cavity; therefore, they have developed a high resistance to localized demineralization. Nevertheless, the continuous demineralization–remineralization cycle present in the oral environment can be influenced by stress, medication, mineralization agents, and other factors such as individual habits, especially diet. In this study, based on attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) spectra from tooth samples of 36 patients, several parameters were estimated: the crystallinity index (CI), the phosphate/amide I ratio, and the carbonate/phosphate ratio. In addition, in eight representative samples (six of the root of the tooth and two of the enamel area of the crown), additional characterization by X-ray powder diffraction (XRPD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) was conducted. From the FTIR data, it was observed that the highest CI values were found in patients who smoked. Further, in both root and crown samples, the intensity of the absorption band corresponding to PO43- increased in patients undergoing treatment with psychotherapeutic drugs. On the other hand, the intensity of the absorption band of the amide I group decreased with medical treatment and with the patient's biological age. Moreover, it was found that the remineralization process was more active in enamel than in the root due to direct contact with saliva. Regarding the results obtained from the X-ray powder diffractograms, exposure to psychotherapeutic drugs affected the definition of the peaks corresponding to hydroxyapatite, both in the crown and root samples. Concerning SEM results, qualitative differences in the stratification process in demineralized surfaces were observed, and EDS analyses showed some differences in the Ca/P ratio between pathological samples and control ones, but without clear patterns. The above techniques, in particular ATR-FTIR, showed promise for the investigation of the effect of changes produced in the hydroxyapatite structure in teeth and, consequently, to determine possible strategies in the diagnostic protocol

Toxicity of the anti-ribosomal lectin ebulin f in lungs and intestines in elderly mice

Producción CientíficaAll parts of dwarf elder (Sambucus ebulus L.) studied so far contain a ribosome-inactivating protein with lectin activity (ribosome-inactivating lectin; RIL), known as ebulin. Green fruits contain ebulin f, the toxicity of which has been studied in six-week-old mice, where it was found that the intestines were primary targets for it when administered intraperitoneally (i.p.). We performed experiments to assess whether ebulin f administration to six- and 12-month-old mice would trigger higher toxicity than that displayed in six-week-old mice. In the present report, we present evidence indicating that the toxicological effects of ebulin f after its i.p. administration to elderly mice are exerted on the lungs and intestines by an increased rate of apoptosis. We hypothesize that the ebulin f apoptosis-promoting action together with the age-dependent high rate of apoptosis result in an increase in the lectin’s toxicity, leading to a higher lethality level.Universidad Complutense de Madrid (research group 950247

La histología y la ingeniería tisular a través de su sociedad científica: la Sehit

La SEHIT tiene su raíz en la Sociedad Histológica de Madrid, fundada en 1873 por el primer Catedrático de Histología Normal y Patológica de España, Aureliano Maestre-de San Juan. Refundada en 1977 con el nombre de Sociedad Española de Histología, pasó a denominarse en 2003 Sociedad Española de Histología e Ingeniería Tisular. Diferentes nombres, pero siempre el mismo espíritu y fines, encaminados al intercambio de conocimientos y colaboración, promoción de las disciplinas que comprende y exaltación de la memoria de los que destacan en éstas. La Sociedad celebra un congreso internacional con periodicidad bienal y simposios en los años entre congresos, además de otros actos y actividades por internet. La Histología trata del estudio de los tejidos biológicos con las células y matriz extracelular que los componen y cómo dichos tejidos se integran para formar los órganos, atendiendo a su estructura, composición química y funciones, en estado de salud. Para ello, utiliza instrumentos amplificantes de la visión, fundamentalmente el microscopio, abarcando una dimensión multinivel que se extiende desde las macromoléculas al terreno de la observación macroscópica; y con las modernas técnicas de que se vale, puede llegar a localizar procesos celulares, integrando así estructura y función. La Histología constituye la base de la Anatomía, Fisiología e Histopatología y, más recientemente, también se ha constituido en terapéutica por su proyección en la Ingeniería Tisular, disciplina que, utilizando mediadores químicos, biomateriales y cultivos celulares, tiene como objeto la reparación de los tejidos y órganos, así como la fabricación artificial de los mismos, contribuyendo, además, al desarrollo de organoides en chip. A todo ello debemos añadir el orgullo de que nuestro más insigne histólogo, Ramón y Cajal, fuera galardonado con el Premio Nobel y que las preparaciones histológicas son fuente de gran belleza a través de los maravillosos paisajes que ofrecen, sólo accesibles a aquel que se aventura a mirar por el microscopi

In vivo toxicity of the ribosome- inactivating lectin ebulin f in elderly mice

Ebulin f is a ribosome-inactivating protein (RIP) present in green fruits of the dwarf elder (Sambucus ebulus L). Since dwarf elder fruits are used for food and as a medicine, we assessed the study of toxicological effects and safety of ebulin f in elderly mice, comparing these results with those reported in young animals and with other RIPs. Female Swiss mice aged 6 and 12 months of age were intraperitoneally injected with a single dose from 1.4 to 4.5 mg/kg ebulin f. Heart, stomach, intestines, lung, kidney, liver, spleen, pancreas, adrenal gland, uterus, ovary and brain were studied. Histology analysis was carried out by staining with hematoxylin and eosin and Masson’s trichrome observed with a light microscope, or apoptosis detection by TUNEL method observed with a confocal laser microscope. Treated animals injected with the lower dose could recover their weights, but after 14 days half of them died. The higher dose caused a progressive loss of body weight leading to death. In the animals of the experimental groups it was found atrophy of Lieberkühn’s crypts, pneumonia, nephronal degeneration, myocardial atrophy, centrolobular hepatic necrosis, splenic white pulp necrosis foci and increased rate of apoptosis in the intestines and liver, in which apoptoses were mainly located in the vicinity of the lobular central vein. We conclude that ebulin f affects vital organs in elderly mice

Atlas virtual de preparaciones citológicas e histológicas

El proyecto se ha llevado a cabo por profesores de los departamentos de Biología Celular de las Universidades de Salamanca, Valladolid y Valencia. Se ha elaborado un atlas de imágenes citológicas e histológicas en dos formatos, CD-ROM y página web. El CD-ROM se ha realizado para que funciones tanto en plataforma PC como Apple. Se han incluido más de mil imágenes de preparaciones histológicas de gran calidad. Las imágenes son variadas en su técnica, plano de corte, magnificación y de cada una de ellas se presenta una imagen a tamaño medio y otra a pantalla completa. Además se presenta de cada una de ellas una 'ciega' para que el alumno compruebe sus conocimientos y pueda hacer autoevaluación y otra 'rotulada' donde se identifican los componentes principales de esa preparación. El CD-ROM se ha organizado en un índice con dos entradas: por tejidos y por sistemas animales. A su vez, cada una de estas entradas se divide en una serie de apartados en los que se describe cada tejido y los diferentes órganos que constituyen cada sistema. En los textos se describen cada tejido y los diferentes órganos que constituyen cada sistema. En los texto se describen las principales características, composición, tipos celulares y sustancia intercelular. También se señalan las funciones más significativas, variaciones filogenéticas, origen, etc. El objetivo del proyecto es conseguir un nuevo recurso para las clases prácticas con más potencia, más flexibilidad y más económico. Además se pretende mejorar la calidad de la enseñanza y la motivación del alumno. El CD-ROMj que se ha elaborado supone un método complementario a la Enseñanza Clásica. Se trata de recursos propios, flexibles y adaptables para la utilización en asignaturas de la Universidad, seminarios, conferencias y podrá ser compartido por diferentes profesores y utilizado por el alumno. El CD-ROM no está publicado.Junta de Castilla y León. Dirección General de Universidades e Investigación. Monasterio Ntra. Sra. del Prado. Autovia Puente Colgante s/n. 47071 Valladolid. Teléfono: 983-41.18.87Castilla y LeónES