Oclusión venosa retiniana en pacientes menores de 50 años. Análisis de factores de riesgo vascular, trombofilia, hallazgos ecográficos carotídeos y etiologías poco frecuentes / Retinal vein occlusion in patients under 50 years. Analysis of vascular risk factors, thrombophilia, carotid ultrasound findings and uncommon aetiologies

Introducción La oclusión venosa retiniana (OVR) se ha relacionado con factores de riesgo vascular y trombofilia. Métodos Se trata de un estudio de cohorte prospectivo de todos los pacientes diagnosticados de OVR y remitidos a una clínica de medicina interna de un hospital universitario terciario durante un período de 10 años. Se analizaron variables clínicas, de laboratorio y ecográficas de troncos supraaórticos y se compararon según la edad. Resultados Se incluyeron unos 309 pacientes diagnosticados de OVR, 25 de ellos menores de 50 años. La prevalencia de hipertensión arterial, dislipidemia, diabetes mellitus, hiperhomocisteinemia y placa carotídea fue significativamente mayor en pacientes > 50 años que en los menores. Sin embargo, la prevalencia de trombofilia hereditaria fue mayor en el grupo más joven (32 vs. 11,4%; p = 0,005). Se observaron enfermedades poco frecuentes relacionadas con la OVR como hepatitis C, talasemia menor, enfermedad de Lyme, vasculitis y perlebitis en pacientes jóvenes sin factores de riesgo vascular. Conclusión Sugerimos realizar un estudio genético de trombofilia en pacientes con OVR menores de 50 años, siendo siempre recomendable un control exhaustivo de los factores de riesgo vascular en todos los pacientes con OVR. Además, sugerimos tener en cuenta las enfermedades poco frecuentes relacionadas con la OVR, especialmente en pacientes jóvenes sin factores de riesgo vascular (AU)

Introduction Retinal vein occlusion (RVO) has been related to vascular risk factors and thrombophilia. Methods This is a prospective cohort study of all patients diagnosed with RVO and referred to an Internal Medicine clinic of a tertiary teaching hospital during a 10-year period. Clinical, laboratory and supra-aortic trunks ultrasound variables were analysed and compared according to age. Results Some 309 patients diagnosed with RVO were included, 25 of them younger than 50 years. The prevalence of high blood pressure, dyslipidaemia, diabetes mellitus, hyperhomocysteinemia, and carotid plaque was significantly higher in patients>50 years than in those below. However, the prevalence of inherited thrombophilia was higher in the younger group (32.0 vs 11.4%; p = 0.005). Uncommon diseases related to RVO such as hepatitis C, thalassemia minor, Lyme disease, vasculitis, and periphlebitis were observed in young patients without vascular risk factors. Conclusion We suggest performing a genetic thrombophilia study in RVO patients younger than 50 years, while an exhaustive control of vascular risk factors is always recommended in all RVO patients. Moreover, we suggest bearing in mind uncommon diseases related to RVO, especially in young patients without vascular risk factors (AU)

Retinal vein occlusion in patients under 50 years. Analysis of vascular risk factors, thrombophilia, carotid ultrasound findings and uncommon aetiologies.

INTRODUTION: Retinal vein occlusion (RVO) has been related to vascular risk factors and thrombophilia. METHODS: This is a prospective cohort study of all patients diagnosed with RVO and referred to an Internal Medicine clinic of a tertiary teaching hospital during a 10-year period. Clinical, laboratory and supra-aortic trunks ultrasound variables were analysed and compared according to age. RESULTS: Some 309 patients diagnosed with RVO were included, 25 of them younger than 50 years. The prevalence of high blood pressure, dyslipidaemia, diabetes mellitus, hyperhomocysteinemia, and carotid plaque was significantly higher in patients >50 years than in those below. However, the prevalence of inherited thrombophilia was higher in the younger group (32.0% vs 11.4%; p = 0.005). Uncommon diseases related to RVO such as hepatitis C, thalassemia minor, Lyme disease, vasculitis, and periphlebitis were observed in young patients without vascular risk factors. CONCLUSION: We suggest performing a genetic thrombophilia study in RVO patients younger than 50 years, while an exhaustive control of vascular risk factors is always recommended in all RVO patients. Moreover, we suggest bearing in mind uncommon diseases related to RVO, especially in young patients without vascular risk factors.

Fractal signatures of the COVID-19 spread.

Recent quantitative approaches for studying several aspects of urban life and infrastructure have shown that scale properties allow the understanding of many features of urban infrastructure and of human activity in cities. In this paper, we show that COVID-19 virus contamination follows a similar pattern in different regions of the world. The superlinear power-law behavior for the number of contamination cases as a function of the city population, with exponent ß of the order of 1.15 is always obtained. Due to the strong indication that scaling is a determinant feature of covid-19 spread, we propose an epidemiological model that embodies a fractal structure, allowing a more detailed description of the observed data about the virus spread in different countries and regions. The hypothesis that fractal structures can be formed in cities as well as in larger networks is tested, indicating that indeed self-similarity may be found in networks connecting several cities.

Synthesis and characterization of a biocompatible chitosan-based hydrogel cross-linked via 'click' chemistry for controlled drug release.

A chemically cross-linked chitosan-based hydrogel was successfully synthesized through Diels-Alder (DA) reaction and characterized. The final product was obtained after different steps; on the one hand, furan-modified chitosan (Cs-Fu) was synthesized by the reaction of furfural with the free amino groups of chitosan. On the other hand, highlighting the novelty of the present research, maleimide-functionalized chitosan (Cs-AMI) was prepared by the reaction of a maleimide-modified aminoacid with the amino groups of chitosan through amide coupling. The two complementary chitosan derivatives were cross-linked to the final hydrogel network. Both modification reactions were confirmed by FTIR and 1H NMR, obtaining a degree of substitution (DS) of 31% and 26% for Cs-Fu and Cs-AMI, respectively. The as-designed hydrogel was analyzed in terms of microstructure, swelling capacity and rheological behaviour. The hydrogel showed pH-sensitivity, biocompatibility and inhibitory bacterial activity, promising features for biomedical applications, particularly for targeted-drug delivery.

HR007: a family of biomaterials based on glycosaminoglycans for tissue repair.

Most new advances in tissue engineering (TE) focus on the creation of adequate microenvironments that may accelerate the repair processes of damaged tissues. Extracellular matrix (ECM) of Wharton's jelly (WJ) from umbilical cords is very rich in sulphated GAGs (sGAGs) and hyaluronic acid (HA), components which have special properties that could positively influence the regeneration of several types of tissue. Previously, we described the methodology for the extraction and purification of GAGs from WJ and, importantly, the separation of sGAGs and HA to develop various scaffolds for regenerative medicine. In this new study we hypothesized that the biomaterials obtained, called HR007s, would be excellent candidates for two different applications, chondral and dermal repair. First, we have confirmed that the GAGs obtained are biocompatible, as they do not cause cytotoxicity, haemolysis or an inflammatory response. Second, we have developed three-dimensional (3D) structures through the combination of different ratios of GAGs and their subsequent stabilization, which can be properly adapted to target tissues, cartilage or skin. Finally, we have combined these scaffolds with adipose mesenchymal stem cells (ASCs) or fibroblasts for application to chondral or dermal defects, respectively, with the goal of promoting fast reparative processes. The results show that HR007 scaffolds induce cell proliferation, enhance the expression of specific gene markers, increase the production of tissue ECM proteins and have chemotactic effects over the studied cells. In summary, the bioactive properties of HR007 scaffolds make them promising candidates for use in regenerative medicine, at least for chondral and dermal repair. Copyright © 2015 John Wiley & Sons, Ltd.

Indoleamine 2,3 dioxygenase as a prognostic and follow-up marker in melanoma. A comparative study with LDH and S100B.

BACKGROUND: To date, lactate dehydrogenase (LDH) and S100B remain the most useful biomarkers for follow-up of melanoma patients. In recent years, indoleamine 2,3-dioxygenase (IDO), an immunosuppressive enzyme, has been proposed as a new potential tumour biomarker for melanoma. However, further studies are needed to confirm the usefulness of IDO expression as an independent prognostic factor. OBJECTIVE: To explore the potential association between serum IDO levels and melanoma stage at diagnosis and recurrence, and to compare the results to those obtained with LDH and S100B. In addition, we also investigated a possible cut off for IDO level as a prognostic factor for overall survival. METHODS: IDO, LDH and S100B levels were measured in serum samples of 186 patients in all melanoma stages at diagnosis and twice a year thereafter. A cut-off point for IDO levels was calculated using receiver operating characteristic curves to explore the association between these levels and the likelihood of lymphatic spread. Survival curves were estimated for patient groups stratified by IDO level (higher or lower than the cut off), using the Kaplan-Meier method. RESULTS: At diagnosis, serum IDO levels were significantly higher in stages IB, II, III and IV, whereas S100B levels were significantly higher in stages III and IV, and LDH levels were only higher in stage IV. In relapsed patients, significant increases were found in levels of all three markers. Finally, overall survival was significantly longer in patients with IDO levels below a cut off of 1.65 µM at diagnosis than in those with higher levels (91.3 vs. 71.0% at 36 months). CONCLUSION: In melanoma patients, serum IDO levels are significantly associated with disease stage, relapses and overall survival. These results indicate IDO could be a useful serum prognostic marker for melanoma.

Generation of tunable glycosaminoglycan hydrogels to mimic extracellular matrices.

Biomaterials and, especially, scaffolds may function as temporary extracellular matrix (ECM), mimicking in vivo environmental structures and facilitating cell growth and tissue regeneration. ECM is composed mostly of glycosaminoglycans (GAGs) and proteins, the ratio of GAGs, hyaluronic acid (HA):sulphated GAGs (sGAGs) being characteristic of each type of tissue. Umbilical cord (UC) and particularly Wharton's jelly (WJ) have been proposed as good sources for obtaining GAGs. In this work, we present a novel methodology for the extraction, purification and separation of GAGs from UC obtained from two different species, human and pig. The new methodology is based on enzymatic digestion of WJ, precipitation of GAGs with organic solvents, purification steps and chromatographic separation of GAGs using ion exchange columns. This novel process allows highly purified HA and sGAGs to be obtained from human and pig WJ. The composition of sGAGs and molecular weight of HA were very similar in the two species and GAGs are haemocompatible and non-cytotoxic. Finally, these new biomaterials have significant bioactive properties, increasing proliferation rates of two cell lines, human adipose mesenchymal stem cells (ASCs) and fibroblasts. In summary, the separation of HA and sGAGs, linked to the improvement in the GAG quantification method described in this paper, opens new avenues for the formulation of natural biomaterials with various ratios of GAGs, mimicking tissue matrix for different tissue-engineering applications. Copyright © 2014 John Wiley & Sons, Ltd.

A study of the mechanical properties and cytocompatibility of lactide and caprolactone based scaffolds filled with inorganic bioactive particles.

The mechanical properties of highly porous (90% porosity) poly(l-lactide) (PLLA), poly(ε-caprolactone) (PCL) and poly(l-lactide/ε-caprolactone) (PLCL) were investigated. Young's modulus of non-porous PLLA, PCL and PLCL dropped from 2263.4, 183.7 and 5.7 MPa to 16.8, 1.0 and 1.0 MPa, respectively, for their ~90% porous counterparts. Elongation at break of PCL decreased noticeably with porosity fraction while PLCL maintained a highly elastomeric character and strain recovery capacity even in the presence of pores. Inorganic bioactive particles (hydroxyapatite or bioglass) were added to confer bioactivity to the aforementioned synthetic bioresorbable polymers, and their effect on the mechanical properties was also investigated. Addition of 15 vol.% of inorganic bioactive particles increased the Young's modulus of highly porous PLLA from 16.2 to ~30 MPa. On the contrary, the difference between Young's modulus of filled and unfilled PCL and PLCL scaffolds was not statistically significant. Finally, an in vitro study of the cytocompatibility and adhesion of adipose derived stem cells (ADSCs) was conducted. The observed viability and excellent adhesion of these cells to both porous and non-porous templates indicate that the employed materials can be good candidates for application in tissue engineering.

Crystallinity assessment and in vitro cytotoxicity of polylactide scaffolds for biomedical applications.

Bioresorbable polylactides are one of the most important materials for tissue engineering applications. In this work we have prepared scaffolds based on the two optically pure stereoisomers: poly(L: -lactide) (PLLA) and poly(D: -lactide) (PDLA). The crystalline structure and morphology were evaluated by DSC, AFM and X-ray diffraction. PLLA and PDLA crystallized in the α form and the equimolar PLLA/PDLA blend, crystallized in the stereocomplex form, were analyzed by a proliferation assay in contact with mouse L-929 and human fibroblasts and neonatal keratinocytes for in vitro cytotoxicity evaluation. SEM analysis was conducted to determine the cell morphology, spreading and adhesion when in contact with the different polymer surfaces. The preserved proliferation rate showed in MTT tests and the high colonization on the surface of polylactides observed by SEM denote that PLLA, PDLA and the equimolar PLLA/PDLA are useful biodegradable materials in which the crystalline characteristics can be tuned for specific biomedical applications.

Distribution of peptidase activity in teleost and rat tissues.

Peptides play important roles in cell regulation and signaling in many tissues. The actions of peptides are regulated by peptidases. Although the activity of these enzymes has been thoroughly characterized in mammals, little is known about their presence or function in fish. In the present study, we compared the activity of several peptidases in selected tissues (pituitary gland, different brain areas, kidney and gills) of the gilthead sea bream and rainbow trout with that found in similar rat tissues (lungs studied in place of gills). Soluble puromycin-sensitive aminopeptidase showed the highest values in the pituitary gland of the sea bream, whereas the membrane-bound form was found to be more active in the trout kidney. Very high levels of activity of aminopeptidase N were detected in trout and sea bream plasma. In contrast, the highest levels of activity of aminopeptidase B were found in rat tissues, with the exception of the gills of the trout. Aminopeptidase N levels tended to be higher in sea bream tissues with respect to those of trout. In contrast, the level of activity of aminopeptidase B was found to be consistently much higher in trout tissues than in those of the sea bream. Prolyl endopeptidase activity was principally detected in the pituitary gland and in the brain areas of teleosts. These differences between species could be related to different mechanisms of osmoregulation in saltwater- and in freshwater-adapted fish.

Effects of all-trans retinoic acid on tumor recurrence and metastasis.

OBJECTIVE: All-trans-retinoic acid (ATRA) promotes cell differentiation. We have studied its effect on the local recurrence and metastatic spreading of an experimental rhabdomyosarcoma in rats. DESIGN: syngenic rhabdomyosarcoma cells (S4MH) were inoculated s.c. in male WAG/RijCrl rats. After 25 days tumors were excised and a 40% hepatectomy was performed for all animals. Ten days later the rats were sacrificed and a thorough necropsy was performed. The animals were randomly allocated to receive daily doses of ATRA (5 mg/kg, i.p.) or its solvent (Clinoleic/ethanol 90/10), starting three days before surgery until the end of the experiment. RESULTS: ATRA reduced the incidence of local recurrence from 70 to 33% (p < 0.05), but the tumor size was not altered (1.8 vs. 2.0 cc). Regarding inguinal metastasis, there was a six-fold decrease (0.2 vs. 1.2 cc; p < 0.05) in mean tumor volume, although the rate of this proliferation increased sharply (86 vs. 29%; p < 0.05) for treated animals. The volume of the retroperitoneal tumor masses also decreased with ATRA (0.7 vs. 5.1 cc; p < 0.05), but the difference in rate was not significant (71 vs. 67%). Lung metastases, which were present in 100% of control animals, were found in only 33% of treated rats, while the mean number of metastatic foci dropped from 26.7 to 5.7 (p < 0.05). CONCLUSION: Protocols including retinoid administration prior to and following primary tumor excision could help in controlling both recurrence and metastatic progression in surgically treated rhabdomyosarcoma.

Efecto del ácido trans-retinoico sobre la recidiva tumoral y el desarrollo metastásico / Effects of all-trans retinoic acid on tumor recurrence and metastasis

Objetivo: el ácido trans-retinoico (ATRA, "all-trans retinoic acid") es un agente inductor de la diferenciación celular. Se estudia su efecto sobre la recidiva local y la diseminación metastásica de los tumores sólidos. Diseño experimental: mediante inoculación subcutánea de células de rabdomiosarcoma (S4MH) se ha inducido un tumor en ratas WAG/RijCrl. Tras 25 días, se practicó una tumorectomía y simultáneamente hepatectomía del 40%. Los animales se sacrificaron el día 35, y fueron sometidos a estudio necrópsico. La mitad de los animales fueron tratados con ATRA (5 mg/kg, i.p.) desde el día 22 al 35, mientras que los controles recibieron el excipiente (Clinoleico®/etanol 90/10). Resultados: el tratamiento redujo la tasa de recidiva local del 70 al 33% (p < 0,05), aunque no afectó a su tamaño (1,8 vs. 2,0 cc). El volumen medio de las metástasis inguinales se redujo a la sexta parte (0,2 vs. 1,2 cc; p < 0,05), si bien su frecuencia aumentó con el ATRA (86 vs. 29%; p < 0,05). La extensión retroperitoneal del rabdomisoarcoma también se redujo (0,7 vs. 5,1 cc; p < 0,05), aunque no hubo variación en la incidencia (71 vs. 67%). La incidencia de afectación pulmonar (100% en controles) se redujo hasta el 33% (p < 0,05), a la vez que el número medio de focos en el pulmón pasó de 26,7 a 5,7 (p < 0,05). Conclusión: la estrategia terapéutica fundamentada en el tratamiento pre y postextirpación quirúrgica con retinoides podría favorecer el control local de rabdomiosarcomas sometidos a cirugía

Objective: all-trans-retinoic acid (ATRA) promotes cell differentiation. We have studied its effect on the local recurrence and metastatic spreading of an experimental rhabdomyosarcoma in rats. Design: syngenic rhabdomyosarcoma cells (S4MH) were inoculated s.c. in male WAG/RijCrl rats. After 25 days tumors were excised and a 40% hepatectomy was performed for all animals. Ten days later the rats were sacrificed and a thorough necropsy was performed. The animals were randomly allocated to receive daily doses of ATRA (5 mg/kg, i.p.) or its solvent (Clinoleic®/ethanol 90/10), starting three days before surgery until the end of the experiment. Results: ATRA reduced the incidence of local recurrence from 70 to 33% (p < 0.05), but the tumor size was not altered (1.8 vs. 2.0 cc). Regarding inguinal metastasis, there was a six-fold decrease (0.2 vs. 1.2 cc; p < 0.05) in mean tumor volume, although the rate of this proliferation increased sharply (86 vs. 29%; p < 0.05) for treated animals. The volume of the retroperitoneal tumor masses also decreased with ATRA (0.7 vs. 5.1 cc; p < 0.05), but the difference in rate was not significant (71 vs. 67%). Lung metastases, which were present in 100% of control animals, were found in only 33% of treated rats, while the mean number of metastatic foci dropped from 26.7 to 5.7 (p < 0.05). Conclusion: protocols including retinoid administration prior to and following primary tumor excision could help in controlling both recurrence and metastatic progression in surgically treated rhabdomyosarcoma

[Survival of dopaminergic neurons that were hibernated in vitro for seven days]. / Supervivencia in vitro de neuronas dopaminérgicas hibernadas durante siete días.

INTRODUCTION: The use of fresh foetal tissue in neurotransplants entails considerable problems of logistics that limit its clinical applicability, something that can be resolved by the development of optimal tissue storage procedures that do not affect in vivo viability and survival of dopamine. AIMS. To determine whether 7 days' hibernation affects the survival of mesencephalic tissue in vitro, and to compare it to fresh tissue. MATERIALS AND METHODS: The midbrains of rats were hibernated for 1, 3, 5 and 7 days at 4 degrees C. A cellular suspension was prepared for culture throughout a 7-day period. The number of TH+ cells present in the fresh and hibernated cultures was determined. RESULTS: The morphology of the hibernated and cultured dopaminergic neurons was very similar to that of the fresh cells. Comparing the viability of the hibernated and fresh cells did not reveal any significant differences. No significant differences between the numbers of TH+ neurons were observed at any of the hibernation times. The lowest rate of TH+ cell survival was reached at seven days' hibernation. Significant differences (p < 0.05) were found between the number of TH+ neurons for fresh and hibernated tissue. CONCLUSIONS: Hibernation at 4 degrees C for up to five days guarantees the survival of TH+ cells in vitro, but it is affected by longer times. This procedure could be considered useful for preserving human tissue in clinical transplant applications. These results refer to in vitro conditions; therefore, studies must be conducted to investigate the survival and functionality of hibernated and transplanted neurons in animal models to enable us to evaluate its applicability in neurorestorative therapy.

[Marrow stromal cells cultured in N2-supplemented medium: implications on the generation of neural cells]. / Cultivo de las células estromales de la médula ósea en un medio suplementado con los nutrientes N2: implicaciones sobre la generación de células neurales.

INTRODUCTION: Most of the culture system for in vitro maintenance and neural differentiation of marrow stromal cells (MSCs) use synthetic media supplemented with 10 or 20% fetal bovine serum (FBS). Serum, however, is comprised of unknown quantities of undefined substances which could interfere the effect of exogenous substances on neural differentiation of MSCs. AIM. Here we describe survival of MSCs cultured in culture conditions where serum was reduced at 0.5 and 1% using Bottenstein and Sato's N2 formula (1979) and poly-L-lysine (PLL)-coated substrate. MATERIALS AND METHODS: Stromal cells isolated from rat femurs were cultivated in Dulbecco's modified Eagle medium at 10, 1, 0.5% FBS or in serum free medium containing N2 formula. In serum free medium or at low serum concentration culture surface was coated with PLL. Cell survival was determined by MTT method or by counting viable cells. RESULTS: Survival of MSCs cultured in N2 supplement was reduced at about 40% of that observed in 10% FBS containing medium. Under these conditions cell morphology was also affected. When N2 containing medium was supplemented with FBS at 0.5 or 1% a significant increase of survival with respect to that observed in N2-supplemented cultures was observed. Cells seeded on PLL-coated surface increased their survival by contrast with their homologous cultures seeded on uncoated surface. CONCLUSIONS: The culture system which combines N2 formula with FBS 1% and PLL-coated surface is useful for the maintenance of MSCs. These conditions offer advantages for the study of differentiation of these cells because they reduce the confounding influence of serum. The possible implication of this culture system for the study of neural differentiation by these cells is discussed.

Supervivencia in vitro de neuronas dopaminèrgicas hibernadas durante siete dias / s. t

El uso de tejido fetal fresco en el neurotrasplante presenta considerables dificultades logìsticas que limitan su aplicabilidad clìnica . Este aspecto podrìa solucionarse con el desarrollo de procedimientos optimos de almacenamiento del tejido que no afecten a la viabilidad y la supervivencia dopaminèrgica in vivo. Es objetivo del trabajao determinar si la hibernaciòn durante siete dìas influye sobre la supervivencia del tejido mesencefàlico in vitro y comparar el tejido hibernado con el fresco...(AU)

Supervivencia in vitro de neuronas dopaminérgicas hibernadas durante siete días / Survival of dopaminergic neurons that were hibernated in vitro for seven days

Introducción. El uso de tejido fetal fresco en el neurotrasplante presenta considerables dificultades logísticas que limitan su aplicabilidad clínica. Este aspecto podría solucionarse con el desarrollo de procedimientos óptimos de almacenamiento del tejido que no afecten a la viabilidad y la supervivencia dopaminérgica in vivo. Objetivo. Determinar si la hibernación durante siete días influye sobre la supervivencia del tejido mesencefálico in vitro, y comparar el tejido hibernado con el fresco. Material y métodos. El mesencéfalo de rata se hibernó 1, 3, 5 y 7 días a 4 °C. Se preparó la suspensión celular para cultivar durante siete días. Se determinó el número de células TH+ presentes en los cultivos frescos e hibernados. Resultados. La morfología de las neuronas dopaminérgicas hibernadas y cultivadas fue muy similar a la de las células frescas. La comparación de la viabilidad de las células hibernadas con la de las frescas mostró diferencias no significativas. No hay diferencias significativas entre el número de neuronas TH+ observadas en todos los tiempos de hibernación. La supervivencia de células TH+ más baja se alcanzó a los siete días de hibernación. Existen diferencias significativas (p < 0,05) entre el número de neuronas TH+ del tejido fresco y el hibernado. Conclusiones. La hibernación a 4 °C hasta cinco días garantiza la supervivencia in vitro de las células TH+; tiempos mayores, la afecta. Este procedimiento podría considerarse útil para la conservación del tejido humano aplicable en el trasplante clínico. Estos resultados se refieren a condiciones in vitro; por tanto, se requiere estudiar la sobrevivencia y funcionalidad de las neuronas hibernadas y trasplantadas en modelos animales para evaluar su aplicación en la terapia neurorrestaurativa

Introduction. The use of fresh foetal tissue in neurotransplants entails considerable problems of logistics that limit its clinical applicability, something that can be resolved by the development of optimal tissue storage procedures that do not affect in vivo viability and survival of dopamine. Aims. To determine whether 7 days’ hibernation affects the survival of mesencephalic tissue in vitro, and to compare it to fresh tissue. Materials and methods. The midbrains of rats were hibernated for 1, 3, 5 and 7 days at 4 °C. A cellular suspension was prepared for culture throughout a 7-day period. The number of TH+ cells present in the fresh and hibernated cultures was determined. Results. The morphology of the hibernated and cultured dopaminergic neurons was very similar to that of the fresh cells. Comparing the viability of the hibernated and fresh cells did not reveal any significant differences. No significant differences between the numbers of TH+ neurons were observed at any of the hibernation times. The lowest rate of TH+ cell survival was reached at seven days’ hibernation. Significant differences (p < 0.05) were found between the number of TH+ neurons for fresh and hibernated tissue. Conclusions. Hibernation at 4 °C for up to five days guarantees the survival of TH+ cells in vitro, but it is affected by longer times. This procedure could be considered useful for preserving human tissue in clinical transplant applications. These results refer to in vitro conditions; therefore, studies must be conducted to investigate the survival and functionality of hibernated and transplanted neurons in animal models to enable us to evaluate its applicability in neurorestorative therapy

Cultivo de las celulas estromales de la mèdula òsea en un medio suplementado con los nutrientes N2: implicaciones sobre la generaciòn de cèlulas neurales / s. t

Most of the culture system for in vitro maintenance and neural differentiation of marrow stromal cells (MSCs) use synthetic media supplemented with 10 or 20 percent fetal bovine serum (FBS). Serum, however, is comprised of unknown quantities of undefined substances which could interfere the effect of exogenous substances on neural differentiation of MSCs, AIM. Here we describe survival of MSCs cultured in culture conditions where serum was reduced at 0,5 and 1 percent using Bottenstein and Sato's N2 formula (1979) and poly-L-lysine (PLL)-coated substrate...(AU)

Cultivo de las células estromales de la médula ósea en un medio suplementado con los nutrientes N2: implicaciones sobre la generación de células neurales / Marrow stromal cells cultured in n2-supplemented medium: implications on the generation of neural cells

Introducción. La mayoría de los sistemas de cultivo para el mantenimiento in vitro y la diferenciación neural de las células estromales de la médula ósea (CEM) utilizan medios sintéticos suplementados con suero fetal bovino (SFB) al 10 o al 20%. Sin embargo, el suero se compone de cantidades desconocidas de sustancias no definidas que podrían interferir el efecto de las sustancias exógenas sobre la diferenciación neural de estas células. Objetivo. En este trabajo describimos la supervivencia de las CEM en condiciones de cultivo donde se redujo la concentración del SFB al 0,5 y al 1% y se utilizó la fórmula N2 de Bottenstein y Sato (1979) y un sustrato tratado con poli-L-lisina (PLL). Materiales y métodos. Se cultivaron células estromales aisladas de los fémures de rata en el medio de Eagle modificado por Dulbecco, con concentraciones de SFB del 10, el 1 y el 0,5% o en medio libre de suero, que contenían la fórmula N2. En los cultivos crecidos en medios libres de suero o con baja concentración de éste, la superficie de cultivo se trató con PLL. La supervivencia celular se midió por el método del MTT o por recuento de las células vivas. Resultados. La supervivencia de las CEM cultivadas en la fórmula N2 disminuyó hasta aproximadamente el 40% de la observada en el medio con SFB al 10%, y se afectó la morfología celular. Un aumento significativo de la supervivencia con respecto al cultivo en N2 se produjo cuando, además de este nutriente, se añadió SFB al 0,5 y al 1%. En los cultivos sembrados sobre superficies tratadas con PLL la supervivencia celular aumentó en comparación con los sembrados sobre superficies no tratadas. Conclusiones. Este sistema de cultivo que combina la fórmula N2 con SFB al 1% y emplea un sustrato tratado con PLL, es adecuado para el mantenimiento de las CEM. Estas condiciones son ventajosas para estudiar la diferenciación neural de estas células, ya que reducen la interferencia del suero. Se discute la posible implicación de este sistema de cultivo para los estudios de diferenciación neural en estas células

Introduction. Most of the culture system for in vitro maintenance and neural differentiation of marrow stromal cells (MSCs) use synthetic media supplemented with 10 or 20% fetal bovine serum (FBS). Serum, however, is comprised of unknown quantities of undefined substances which could interfere the effect of exogenous substances on neural differentiation of MSCs. Aim. Here we describe survival of MSCs cultured in culture conditions where serum was reduced at 0.5 and 1% using Bottenstein and Sato’s N2 formula (1979) and poly-L-lysine (PLL)-coated substrate. Materials and methods. Stromal cells isolated from rat femurs were cultivated in Dulbecco’s modified Eagle medium at 10, 1, 0.5% FBS or in serum free medium containing N2 formula. In serum free medium or at low serum concentration culture surface was coated with PLL. Cell survival was determined by MTT method or by counting viable cells. Results. Survival of MSCs cultured in N2 supplement was reduced at about 40% of that observed in 10% FBS containing medium. Under these conditions cell morphology was also affected. When N2 containing medium was supplemented with FBS at 0.5 or 1% a significant increase of survival with respect to that observed in N2-supplemented cultures was observed. Cells seeded on PLL-coated surface increased their survival by contrast with their homologous cultures seeded on uncoated surface. Conclusions. The culture system which combines N2 formula with FBS 1% and PLL-coated surface is useful for the maintenance of MSCs. These conditions offer advantages for the study of differentiation of these cells because they reduce the confounding influence of serum. The possible implication of this culture system for the study of neural differentiation by these cells is discussed

[Once weekly fluoxetine, tolerability and safety according to use patterns in the psychiatric clinical practice]. / Fluoxetina semanal. Tolerabilidad y seguridad según patrones de uso en la práctica clínica psiquiátrica.

INTRODUCTION: Treatment with selective serotonin reuptake inhibitors (SSRI) has become generalized in all the medical setting although its efficacy and good tolerability may be affected by long term non-compliance. Once weekly fluoxetine could improve compliance due to the comfort of its use. The objective is to evaluate the safety, tolerability and efficacy of once weekly fluoxetine (90 mg) in a sample of out-patients, following naturalistic criteria in the usual clinical practice. METHOD: A total of 46 patients (age: 41.89 +/- 1.85) who received once weekly fluoxetine for at least 3 months (mean time: 135.24 days) were analyzed retrospectively. Clinical Global Impression of Severity (CGI-S) at the onset and end of the period evaluated, presence of adverse events, drop-out index and impression of patient's satisfaction with the treatment and use pattern were used. RESULTS: The mean of the final CGI-S was 2.09, compared with the onset 3.09 (p < 0.02), indicating significant improvement in the efficacy with once weekly fluoxetine. The most frequent adverse effects were: anxiety (10.87 %), headache (8.69 %) and restlessness (8.69 %) related with once weekly fluoxetine. Compliance was very high at the onset (99 %) and at the end (96 %). Ten patients dropped-out of the treatment (27.74 %), 6 due to appearance of undesirable effects (anxiety, headache and insomnia), three due to voluntary wish and only one due to lack of efficacy. The CGI of satisfaction of clinical global efficacy on the final visit was 1.43 (satisfied-very satisfied) and the CGI of satisfaction for the treatment pattern was 1.17 (very satisfied). CONCLUSION: Change to once weekly fluoxetine generally improves satisfaction of treatment efficacy and its use pattern, although some patients return to the initial regime after adverse effects appear.