Regeneración ósea por medio de células madre en combinación con beta-fosfato tricálcico / Bone regeneration using stem cells in combination with beta-tricalcium phosphate carrier

Objetivo: Estudiar si las células madre adultas mesenquimales en combinación con beta-fosfato tricálcico contribuyen significativamente a la regeneración en una lesión ósea traumatizada. Material y método: Se utilizó un modelo de defecto traumático en el fémur de ratas Wistar (n=39). Fueron diseñados dos grupos: el grupo 1 (control), con nueve ratas a las que se les realizó un defecto óseo vacío; y el grupo 2 (experimental), con tres subgrupos de 10 ratas cada uno, a las que se les administró beta-fosfato tricálcico (β-TCP) y β-TCP en combinación con células madre mesenquimales (MSC). Se valoraron resultados a las tres, seis y nueve semanas de evolución, respectivamente. Resultados: Se observó el 65% de las fracturas en los fémures derechos de las ratas, que en grupo experimental corresponde a la zona donde se implanta el carrie en combinación con las MSC, aunque sólo el 35% de éstas coinciden exactamente con esta zona. No existen diferencias de comportamiento biológico significativas, aunque se demuestra actividad osteogénica. Conclusión: El uso de β-TCP en combinación con células estromales mesenquimales no genera resultados significativos en la regeneración ósea. Todavía es necesario potenciar la investigación en fase experimental (AU)

Objective: To study whether adult mesenchymal stem cells in combination with a carrier of beta-tricalcium phosphate contributes significantly in regenerating bone injury in traumatized. Material and method: A traumatic defect model on the femur was used in Wistar rats (n=38). Two groups were designed: the group 1 (control) with 9 rats to which they there was realized a bone defect empty fault, and the group 2 (experimental), with three subgroups (2a, 2b, 2c) of 10 rat each, which were administered the carrier beta-tricalcium phosphate (β-TCP), and β-TCP in combination with mesenchymal stem cells (MSC). Results were valued to 3, 6 and 9 weeks of evolution, respectively. Results: There were 65% of the fractures in the right femur of rats in the experimental group that corresponds to the area where the carrier is implanted in combination with the MSC, but only 35% of these coincide exactly with this area. No significant differences in biological behavior, although it shows osteogenic activity. Conclusion: The use of β-TCP carrier in combination with mesenchymal stromal cells does not produce significant results in bone regeneration. There is a need for further research in experimental phase (AU)

Ultrastructural study of the kidney subjected to warm ischemia and perfused with inosine.

OBJECTIVES: Renal ischemia, depending on its duration, results in organ function loss to a greater or lesser extent, due to the depletion of the energy cells need for their vital functions. The method of supplying an external energy source that may act as a precursor of ATP, such as inosine, has proved to be protective from a functional point of view. In this work, we aim to reveal the histological ultrastructural bases that underlie this protective effect. METHODS: We studied two groups of rats subjecting the kidneys to different durations of warm ischemia, and compared the histological findings at various parts of the nephron after perfusion with saline or inosine. These findings were compared, in turn, with the normal morphology of a third control group. RESULTS: The histological findings were: 1. No significant lesions after 60 and 120 min of warm ischemia in animals perfused with inosine; and 2. Glomerular and tubular injury after 60 min of warm ischemia in animals perfused with saline. CONCLUSIONS: The saline-perfused animals showed very significant injury at the glomerular and tubular levels after 60 and 120 min of warm ischemia. These lesions were not seen in animals perfused with inosine. The similarity of the morphological findings between the inosine-infused group and the control group suggests that inosine has a protective effect on the morphology of the rat nephron under conditions of warm ischemia for periods shorter than 120 min.

Estudio ultraestructural del riñón sometido a isquemia normotérmica y perfundido con inosina / Ultrastructural study of the kidney subjected to warm ischemia and perfused with inosine

OBJETIVO: La isquemia renal da lugar a la pérdida de función del órgano, en mayor o menor medida, dependiendo del tiempo de la misma como consecuencia del agotamiento de las reservas energéticas que la célula utiliza para sus funciones vitales. El aporte externo de una fuente de energía en forma de un precursor de ATP, como es la INOSINA, ha demostrado ser un método protector desde el punto de vista funcional. Pretendemos en éste trabajo poner de manifiesto las bases histológicas ultraestructurales en las que se basa dicho efecto protector. MÉTODO: Se estudian básicamente dos grupos de ratas y se comparan los hallazgos histològicos de las distintas partes de la nefrona después de perfundirlos con suero fisiológico ó inosina y someter los riñones a distintos tiempos de isquemia normotérmica. Dichos hallazgos se comparan a su vez con la morfología normal de un tercer grupo testigo. RESULTADOS: Los hallazgos histológicos se concretan en: 1- Ausencia de lesiones significativas en los animales perfundidos con inosina a los 60 y 120 min. de isquemia normotérmica. 2- Lesiones glomerulares y tubulares a partir de los 60 min de isquemia normotérmica en los animales perfundidos con suero fisiológico. CONCLUSIONES: Los animales perfundidos con suero fisiológico mostraron lesiones muy importantes a nivel glomerular y tubular a los 60 y 120 min de isquemia normotérmica. Dichas lesiones no se aprecian en los animales perfundidos con inosina. La similitud de los hallazgos morfológicos del grupo perfundido con inosina y el grupo testigo, permite atribuir a la inosina un efecto protector de la morfología de la nefrona de rata bajo condiciones de isquemia normotérmica en periodos inferiores a 120 min (AU)

OBJECTIVES: Renal ischemia, depending on its duration, results in organ function loss to a greater or lesser extent, due to the depletion of the energy cells need for their vital functions. The method of supplying an external energy source that may act as a precursor of ATP, such as inosine, has proved to be protective from a functional point of view. In this work, we aim to reveal the histological ultrastructural bases that underlie this protective effect. METHODS: We studied two groups of rats subjecting the kidneys to different durations of warm ischemia, and compared the histological findings at various parts of the nephron after perfusion with saline or inosine. These findings were compared, in turn, with the normal morphology of a third control group. RESULTS: The histological findings were: 1 ) No significant lesions after 60 and 120 min of warm ischemia in animals perfused with inosine; and 2) Glomerular and tubular injury after 60 min of warm ischemia in animals perfused with saline. CONCLUSIONS: The saline-perfused animals showed very significant injury at the glomerular and tubular levels after 60 and 120 min of warm ischemia. These lesions were not seen in animals perfused with inosine. The similarity of the morphological findings between the inosine-infused group and the control group suggests that inosine has a protective effect on the morphology of the rat nephron under conditions of warm ischemia for periods shorter than 120 min (AU)

Estudio de la regeneración ósea mediante la implantación endomedular de biomateriales / Study of bone regeneration by endomedullar implantation of biomaterials

Ante una pérdida ósea en la clínica tras un accidente, un tumor ouna infección se plantean diferentes posibilidades de reconstrucción.Un modelo experimental válido para el estudio de la osteorregeneraciónse basa en la resección de un defecto diafisario suficiente para impedirla reparación espontánea. La originalidad del tema elegido se cimentaen la utilización, in vivo en un animal de talla media (conejo),de un biomaterial que está compuesto de una base estructural de poli(metacrilato de metilo) (PMMA) (serie 1), al que se añade hidroxiapatita(HA) como material osteoconductor (serie 2) y además, un factor decrecimiento fibroblástico (FGF) como osteoinductor. (serie 3). Tras 2, 4y 8 semanas después de la resección (20mm) e implantación endomedularde los tres tipos de barras (25mm de longitud), se procede al análisisradiológico e histológico. Parece que la reparación esta influida porpropiedades mecánicas de estabilidad, fuerza y carga. La regeneraciónósea en el presente modelo sigue un patrón de desarrollo que va desdelos extremos de resección diafisario a la zona media y siempre a expensasde la cortical radial. De los tres modelos de barras utilizados, losformados por PMMA, HA y bFGF, presentan un proceso de reparaciónmás avanzado, hecho observado tanto radiológica como histológicamente

Faced with bone loss after an accident, different possibilities for reconstructioncan be considered dependent on presence of a tumour orinfection. A valid experimental model for the study of osteoregenerationis based on the resectioning of a faulty diaphyseal, sufficientlydamaged to impede spontaneous healing. The origins of the chosen topicare founded in vivo in an animal of average size (a rabbit); of biomaterialthat is composed of a structured basis polymethyl methacrylate(PMMA) (series 1), to which hidroxyapatite (HA) is added asosteoconductor material (series 2) and also a fibroblast growth factor(FGF) as osteoinductor. (Series 3). 2, 4 and 8 weeks after the resection(20mm) and endomedular implants of the three types of bars (25mm oflength), radiological and histological analysis is carried out. This analysisis done without decalcification. The histological technique ‘Von Kossaand Goldner’ is used for this histological study. It seems that healingis influenced by mechanical properties of stability, force and load. Inthe present model, the osseous regeneration follows a definite path thatgoes from the extremities of diaphyseal resection to the middle areaand is always at the expense of the radial cortical. Of the three types ofbars used, those formed by PMMA, HA and FGF, show a more advancedrepair process, visible as much in radiological analysis as histological

[Malignant epithelioid paravertebral schwannoma (author's transl)]. / Schwannoma epitelioide maligno paravertebral.

Tumors arising from the nerve sheaths are a controversial group of neoplasms because of disagreement regarding the clinical course and histopathologic characteristics. Malignant Schwannoma is a rare entity with aggressive biological behaviour (local infiltration and hematogenous metastases). The tumor arises from Schwann cells and may show diverse histological patterns. A malignant epithelioid paravertebral Schwannoma was diagnosed in a 48-year-old patient. Tumor metastases were demonstrated in the lungs, pericardium, liver, intestine, kidney, adrenals, bones and lymph nodes. The differential diagnosis and literature on this topic are commented on.