Resultado de la implantación de consultas telemáticas en cirugía ortopédica y traumatología durante la pandemia COVID-19 / Result of the implementation of telematic consultations in orthopaedic surgery and traumatology during COVID-19 laparoscopic surgery

La pandemia COVID ha hecho de las consultas telemáticas una herramienta básica en la práctica diaria. El objetivo principal del estudio es valorar los resultados de la aplicación de consultas telemáticas para limitar la movilidad de los pacientes. Son objetivos operativos: proponer un plan de consultas, conocer cómo limita la asistencia a las consultas, definir qué patologías se benefician más con este plan. MATERIAL Y MÉTODOS: Se propone un esquema con la creación de consultas previas a las agendadas para valorar idoneidad y posibilidad de realizarla en acto único no presencial. RESULTADOS: Se han realizado 5.619 consultas con una falta de respuesta telefónica del 19%. El 74% de los pacientes fueron resueltos de forma virtual. Existe diferencia entre unidades, siendo más probable la respuesta telefónica para las consultas de unidad, OR = 0,60 o de traumatología general, OR = 0,67 y menos para los derivados desde urgencias. El 20% de las consultas no se acompañaban de pruebas complementarias. Las consultas de traumatología general, OR = 0,34, control postoperatorio, OR = 0,49, y unidades, OR = 0,40, cumplieron mejor este requisito. De los pacientes restantes, las consultas de traumatología general, OR = 0,50, y las derivadas a unidades, OR = 0,54 fueron las que más se resolvieron sin acudir presencialmente. CONCLUSIONES: Se han resuelto de forma no presencial el 74% de los pacientes que atendieron a la llamada telefónica. El 20% de los pacientes acuden a la visita sin pruebas complementarias. Las consultas de seguimiento de osteosíntesis y postoperatorio de cirugía artroscópica son las que más precisan de ser realizadas de forma presencial

The COVID pandemic has made telematic consultations a basic tool in daily practice. AIMS: The main objective of the study is to assess the results of the application of telematic consultations to limit the mobility of patients. The operational objectives are; to propose a consultation plan, to know how attendance limits consultations and to define which pathologies benefit the most from this plan. METHODS: A scheme is proposed with the creation of pre-scheduled clinic to assess suitability and the possibility of carrying them out in a single non face-to-face act. RESULTS: Phone call to 5,619 patients were made with a lack of response of 19%. The cases of 74% of the patients that answered were resolved virtually. There is a difference between units, obtaining a higher answering rate from patients appointed to specific clinic units, OR = 0.60, or to general trauma ones, OR = 0.67. The lowest answering rate was obtained from those derived from the emergency department. Twenty per cent of the consultations were not accompanied by complementary tests that would have favored the resolution in a single act. The general trauma consultations, OR = 0.34, postoperative control, OR = 0.49, and specific unit ones, OR = 0.40, were the ones that better met this requirement. Out of the remaining patients, the general trauma consultations, OR = 0.50, and those referred to units, OR = 0.54, were the ones that had a higher resolution rate without in- person consultation. CONCLUSIONS: The cases of 74% of the patients who answered the phone call were resolved virtually. Cases of 20% of the patients cannot be solved in a single act because they are derived without complementary tests. Osteosynthesis and postoperative arthroscopic follow-up consultations are the ones that need to be carried out in person the most

Result of the implementation of telematic consultations in orthopaedic surgery and traumatology during COVID-19 laparoscopic surgery. / Resultado de la implantación de consultas telemáticas en cirugía ortopédica y traumatología durante la pandemia COVID-19.

The COVID pandemic has made telematic consultations a basic tool in daily practice. AIMS: The main objective of the study is to assess the results of the application of telematic consultations to limit the mobility of patients. The operational objectives are; to propose a consultation plan, to know how attendance limits consultations and to define which pathologies benefit the most from this plan. METHODS: A scheme is proposed with the creation of pre-scheduled clinic to assess suitability and the possibility of carrying them out in a single non face-to-face act. RESULTS: Phone call to 5,619 patients were made with a lack of response of 19%. The cases of 74% of the patients that answered were resolved virtually. There is a difference between units, obtaining a higher answering rate from patients appointed to specific clinic units, OR = 0.60, or to general trauma ones, OR = 0.67. The lowest answering rate was obtained from those derived from the emergency department. Twenty per cent of the consultations were not accompanied by complementary tests that would have favored the resolution in a single act. The general trauma consultations, OR = 0.34, postoperative control, OR = 0.49, and specific unit ones, OR = 0.40, were the ones that better met this requirement. Out of the remaining patients, the general trauma consultations, OR = 0.50, and those referred to units, OR = 0.54, were the ones that had a higher resolution rate without in- person consultation. CONCLUSIONS: The cases of 74% of the patients who answered the phone call were resolved virtually. Cases of 20% of the patients cannot be solved in a single act because they are derived without complementary tests. Osteosynthesis and postoperative arthroscopic follow-up consultations are the ones that need to be carried out in person the most.

Performance of butyl rubber-based macroporous sorbents as passive samplers.

In this study, two macroporous butyl rubber (BR)-based sorbents prepared in benzene (H-BR) and in cyclohexane (L-BR) with different porosities were synthesized by cryogelation technique. Their performances as a passive sampler were studied and then compared with commercially available silicon rubber (polydimethylsiloxane, PDMS) passive sampler. For that aim, polycyclic aromatic hydrocarbon (PAH) absorption rates of the sorbents in the short-term and their accumulation capacities in the long-term periods were investigated. Four PAHs (naphthalene, phenanthrene, fluoranthene, and pyrene) with a different number of aromatic rings were utilized. The concentrations of the PAHs in solutions were quantified by fluorescence spectrophotometer. The results showed that the BR sampler prepared in benzene (H-BR) generally has the highest absorption rates for all PAHs. The rate constants k (h-1) of the H-BR, L-BR, and PDMS samplers were found as 1.07, 0.55, and 0.55 for naphthalene; 0.73, 0.16, and 0.09 for phenanthrene; 0.24, 0.26, and 0.08 for fluoranthene; and 0.97, 0.38, and 0.17 for pyrene, respectively. The highest PAH absorption capacity was found for the BR sorbents prepared in benzene for all PAHs. Thus, benzene was selected as the organic solvent rather than cyclohexane for further studies in the preparation of butyl rubber-based samplers. The H-BR possessing the highest absorption rate and capacity underlines their usage as a capable passive sampler for both short- and long-term monitoring activities in the aquatic environments.

Single-, Double-, and Triple-Network Macroporous Rubbers as a Passive Sampler.

Over the past decades, large quantities of organic compounds including polycyclic aromatic hydrocarbons (PAHs) entering aquatic systems create acutely toxic effects and chronic abnormalities in aquatic organisms. Passive sampling is an effective technique to detect organic compounds at very low concentrations in water by accumulating them in their structure to a measurable concentration level. Polymeric passive samplers reported so far have a nonporous structure, and hence, the absorption of organic compounds into the passive sampler is governed by their slow diffusion process. We present here novel macroporous rubber sorbents as monophasic passive samplers with tunable pore morphologies, extraordinary mechanical properties, and high sorption rates and capacities for PAHs. Sorbent materials based on single-network (SN), double-network (DN), and triple-network (TN) butyl rubber were prepared via the cryogelation technique from butyl rubber solutions in benzene as the solvent at -18 °C using a sulfur monochloride cross-linker. To obtain macroporous rubbers with DN and TN structures, the reactions were conducted in the macropores of SN and DN rubber networks, respectively. The porous morphology and the mechanical behavior of the rubbers can be tuned by adjusting the weight ratio wR of the network components. The rubbers exhibit two generations of pores, namely, large and small pores with diameters 40-240 and 14-54 µm, respectively. The sizes of both large and small pores decrease and approach each other as wR is increased. Four PAH compounds, namely, naphthalene, phenanthrene, fluoranthene, and pyrene with two to four aromatic rings, dissolved in filtered seawater with a salinity of 22 ppt were used to highlight the correlations between the properties of macroporous rubbers and their absorption rates and capacities. Nonporous silicone rubber reported before as a passive sampler has the lowest absorption rate and capacity as compared to the macroporous rubbers. The SN rubber absorbs most rapidly PAHs because of its largest porosity, whereas the TN rubber with the smallest pores exhibits the highest sorption capacity.

Pollution and toxicity of sediment in potential dredging sites of the Marmara Sea, Turkey.

This study aims to assess the impact of the sediment in the potential dredging areas of the Marmara Sea. To that aim, sediments were analyzed for polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and heavy metals, sources were discussed, and toxicity tests were applied. For assessment, lower and upper limits of Turkish draft regulation (LTR, UTR) and UNEP-MAP's guidance document (LCT, UCT), and effects range low and median (ERL, ERM) were used. Total concentrations were found between 562 and 8643 µg kg-1 for PAHs, 4-36 µg kg-1 for PCBs, and 14-190 µg kg-1 for OCPs. The highest ∑PAH concentrations were measured in Golden Horn, and none of the PAH compounds was above ERM. ERL and UCT were exceeded in Istinye and Golden Horn stations. The highest ∑PCBs and ∑OCPs levels were determined in Izmit Bay (IB). ΣPCBs in IB were higher than ERL and LTR, while ΣDDT were found above ERM and UCT. High concentrations of chromium (∼190 mg kg-1) and copper (∼180 mg kg-1) in Golden Horn and mercury in IB (∼4 mg kg-1) were detected. The highest toxicities were observed in Istinye and Izmit Bay. According to the regulations, none of the sediments can be dumped.

Monitoring of organic pollutants in marine environment by semipermeable membrane devices and mussels: accumulation and biochemical responses.

This study involves the monitoring of organic pollutants using transplanted mussels (Mytilus galloprovincialis) as bioindicator organisms and semipermeable membrane devices (SPMDs) as passive samplers. Mussels and SPMDs were deployed to marinas, shipyards and shipbreaking yards on the coastal area of Turkey and retrieved after 60 days. Polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and organochlorine pesticide (OCP) compounds were analysed with high-resolution GC-MS. Total PAH concentrations in SPMDs and mussels ranged from 200 to 4740 ng g sampler-1 and from 7.0 to 1130 ng g-1 in wet weight (ww). PCB and OCP concentrations in SPMDs changed between 0.04-200 and 4.0-26 ng g sampler-1, respectively. The highest PCB (190 ng g-1 ww) and OCP (200 ng g-1 ww) concentrations in mussels were measured at shipyard stations. A strong correlation was observed between the PAH and PCB concentrations in SPMDs and mussels. Enzyme assays (acetylcholinesterase, ethoxyresorufin-O-deethylase, glutathione S-transferase, glutathion reductase and carboxylesterase activities) were performed as biomarkers to reveal the effects of pollution on the mussels. There was no clear relationship found between the enzyme levels and the pollutant concentrations in mussels. Integrated biomarker responses were calculated to interpret the overall effect of pollutants.

Heavy metal pollution in sediments and mussels: assessment by using pollution indices and metallothionein levels.

In the present work, the concentration of eight metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn) was determined in the sediments and transplanted and native mussels (Mytilus galloprovincialis). The study was conducted in Turkish marinas, shipyards, and shipbreaking yards. The effect of metal pollution was evaluated by determining the levels of metallothionein (MT) in the mussels. The extent of contamination for each single metal was assessed by using the geoaccumulation index (I geo) and enrichment factor (EF). Whereas, to evaluate the overall metal pollution and effect, the pollution load index (PLI), modified contamination degree (mC d), potential toxicity response index (RI), mean effects range median (ERM) quotient (m-ERM-Q), and mean PEL quotient (m-PEL-Q) were calculated. The influence of different background values on the calculations was discussed. The results indicated a significant metal pollution caused by Cu, Pb, and Zn especially in shipyard and shipbreaking sites. Higher concentrations of MT were observed in the ship/breaking yard samples after the transplantation.

Long-term outcome of esophagectomy for primary malignant melanoma of the esophagus: a single-institute retrospective analysis.

Primary malignant melanoma of the esophagus (PMME) is a highly malignant tumor with a poor prognosis. Because PMME is an extremely rare disease, therapeutic strategies against the tumor have yet to be established, and the efficacy of esophagectomy remains unclear. The objective of this study was to evaluate the post-esophagectomy survival of PMME patients. Ten patients who underwent esophagectomy for PMME between March 2005 and April 2013 at the Department of Gastroenterological Surgery, Cancer Institute Hospital, Tokyo, Japan, were identified from the institutional database. We retrospectively retrieved clinical information and data on the long-term outcomes from the patients' records. Survival rates after esophagectomy were calculated by the Kaplan-Meier method, and the hazard ratios of mortality were determined using the Cox's model. A follow-up study of the 10 patients revealed 7 cancer recurrences and 5 deaths. Median survival time was 34.5 months, and 5 of 10 patients survived longer than 2 years. The 1-year disease-free survival rate was 40%, and the 1- and 3-year overall survival rates were 70% and 60%, respectively. Importantly, all three of the non-relapsing patients were histologically confirmed as free of lymph node involvement. The four patients with lymph node metastasis relapsed within 1 year. The disease-free survival was significantly shorter in patients with lymph node involvement than in those without lymph node involvement (univariate hazard ratio = 13.3, 95% confidence interval 1.85-266.4; P = 0.009). In conclusion, esophagectomy might benefit PMME patients with no lymph node metastasis. Further large-scale cohort studies are needed to establish the treatment strategy for PMME.

Bioaccumulation-depuration kinetics and effects of phenanthrene on Mediterranean mussel (Mytilus galloprovincialis).

In this study, Mediterranean mussel species, Mytilus galloprovincialis, were exposed to phenanthrene (PHE) due to its ubiquitousness and bioavailability in the aquatic environment. Kinetic parameters of the PHE bioaccumulation and depuration were calculated for an 11-day uptake and subsequent 11-day depuration periods. Those values of kinetic rate constants for uptake and depuration of PHE were calculated as varying between 93-177 and 0.18-0.25, respectively. Negative correlation was observed between the PHE concentrations and kinetic rate constants. Bioaccumulation Factors (BAFs) for the mussels exposed to different PHE concentrations were calculated from both kinetic rate constants and from the experimental data and found between 509-701 and 441-658, respectively. Experimental quantitative structure activity relationship (QSAR) values for PHE were found comparable to the calculated QSARs reported in literature. Two sub-lethal biomarker methods (filtration rate and lysosomal stability) were applied to observe the responses of the mussels throughout the experimental period. Results of both biomarkers show that PHE negatively affects mussels during the uptake of PHE, and mussels were able to recover physiologically at the end of depuration period according to the filtration rate results.

Determination of selected antibiotics in the Istanbul strait sediments by solid-phase extraction and high performance liquid chromatography.

Surface sediments from 12 different locations of the Istanbul Strait and Marmara Sea, Turkey were analysed for five antibiotics belonging to two different groups of widely used pharmaceuticals, tetracyclines (TCs) and fluoroquinolones (FQs), by solid-phase extraction and high performance liquid chromatography. These two groups of antibiotics, mainly used to prevent or treat illness for humans as well as for animals, are frequently detected in the effluent of municipal sewage plants, in the aquatic environments and in soils after being spread by liquid manure. The results of analysis revealed that measured concentrations of individual antibiotics were significantly different depending on sampling location. Chlortetracycline (CTC) was not detected in any of the samples. High concentrations were mainly found in urbanized regions of the Strait. The concentrations of the two tetracyclines ranged from not detectable to 27.3 µg kg(-1) in freeze-dried marine sediments. Comparable results were obtained for the two fluoroquinolones with concentration levels from 1.3 µg kg(-1) up 34.1 µg kg(-1). This study is the first attempt to show the contamination degree of the Istanbul Strait sediments by emerging contaminants. Particular concern should be given concerning their potential side effects caused by the frequent consumption of mussels and fishes captured in the Istanbul Strait.

Distribution of organochlorine pesticides in sediments and mussels from the Istanbul Strait.

This study was conducted to determine the status and trends of organochlorine pesticide (OCP) compounds in the sediment and mussel samples collected along the Istanbul Strait and from the coasts of an island in the Marmara Sea. The total concentrations of OCPs were found in the range of 40-13,852 pg g(-1) dry weight for sediments and 5,195-12,322 pg g(-1) wet weight for mussels. The levels of OCPs in both sediments and mussels were dominated by DDTs and HCHs; ß-HCH, 4,4(')-DDD and 4,4(')-DDE were the major pollutants. The degree of sediment pesticide contamination was more severe in the inner part of the strait. OCP concentrations in sediments and mussels were compared with the sediment guideline values and legal limits for human health, respectively. The results showed that OC pesticide contamination in the strait might not pose a serious threat to the health of the marine inhabitants at most of the stations.

Evaluation of butyl rubber as sorbent material for the removal of oil and polycyclic aromatic hydrocarbons from seawater.

Ecological disasters resulting from oil spills have created a great need to find more efficient materials for oil spill cleanup. This research highlights the use of a novel macroporous polymeric material based on butyl rubber (BR) as a sorbent in an oil spill cleanup. The sorption capacity of BR for crude oil and petroleum products is 15-23 g g(-1) as compared to the value of 10-16 g g(-1) obtained using a nonwoven polypropylene (PP), a widely used commercial oil sorbent. BR sorbent is reusable after simple squeezing and its continuous sorption capacity for crude oil is 7.6 g g(-1) in each cycle, about 3 times the capacity of the PP sorbent BR sorbents also remove efficiently polycyclic aromatic hydrocarbons (PAHs) such as acenaphthene and pyrene from seawaters. The results suggest that the rubber sorbents are a better alternative to the widely used PP sorbents by improving the efficiency of oil sorption and the reusability of the sorbent.

Attenuation of Notch signaling promotes the differentiation of neural progenitors into neurons in the hippocampal CA1 region after ischemic injury.

Intercellular signaling via cell-surface Notch receptors controls the cell-fate decision in the developing brain. Recent studies have suggested that the response of endogenous neural stem cells to brain injury in adult mammals might be mediated by Notch signaling. Here, we investigated the role of Notch signaling in ischemic damage in the hippocampal CA1 region after transient global ischemia in rats. In the acute phase of ischemia, Notch1-positive cells increased in number in the posterior periventricle, which is the posterior part of the lateral ventricle, after the i.c.v. administration of epidermal growth factor and fibroblast growth factor-2. In addition, Notch signaling was upregulated in the CA1 region 5 days after ischemia. By contrast, the attenuation of Notch signaling caused by the administration of a gamma-secretase inhibitor in the subacute phase (6-12 days after ischemia) amplified the immature migratory neurons 12 days after ischemia, and resulted in an increased number of newly generated neurons in the CA1 after 28 days. Our results suggest that Notch signaling in the CA1 is activated in parallel with the increase of endogenous neural stem cells stimulated by ischemia, and that the attenuation of Notch signaling could induce more efficient differentiation of neural progenitors toward a neuronal lineage.

Efecto neuroprotector de las células madre mesenquimales adultas en las fases iniciales de una lesión traumática de la médula espinal / Neuroprotector effect of adult mesenchymal stem cells in the early phases after spinal cord injury

Objetivos: Estudiar el efecto de la administración precoz de células madre adultas mesenquimales sobre la apoptosis en las fases iniciales de un traumatismo medular experimental. Material y métodos: se sometieron 20 ratas Wistar adultas a una lesión traumática estandarizada por contusión, a nivel dorsal medio. Dos horas tras la lesión, 10 animales recibieron una inyección intralesional de 10ml de suero fisiológico y otras 10 recibieron 106 células madre mesenquimales adultas de médula ósea. Cinco animales de cada grupo se sacrificaron a las 8 horas y otros 5 animales a las 72 horas de la lesión. Se realizaron estudios histológicos e histomorfométricos con H&E y con marcador Mab F7-26 (apostain). Resultados: En los animales control, el número medio de células nerviosas expresando apostain fue de 138 ± 16, a las 8 horas de la lesión, y de 82 ± 13, a las 72 horas mientras que en el grupo tratado el número de células nerviosas marcadas con apostain fue de 76 ± 11, a las 8 horas, y de 57 ± 7, a las 72 horas tras la lesión con diferencias estadísticamente significativas entre ambos grupos (p< 0,05). Conclusión: La administración intralesional de células madre mesenquimales adultas ejerce un efecto neuroprotector en las fases precoces de un traumatismo medular grave disminuyendo el número de células nerviosas apoptóticas (AU)

Aim: To study if the intralesional administration of adult mesenchymal stem cells modifies the number of apoptotic nervous cells in the early phases after severe spinal cord injury (SCI). Material and methods: Twenty adult Wistar rats were subjected to SCI at dorsal level. Two hours after the lesion, in 10 animals a volume of 10 ml of saline into the lesion were administered. Other 10 animalsreceived 106 bone marrow stromal cells obtained. Five animals of each group were sacrificed at the 8 hours after the lesion and the other 5 animals at the 72 hours. The spinal cord was processed in each animal for conventional histological studies and to identify cells in apoptosis using the marker Mab F7-26 (apostain). The number of cells in apoptosis with appearance of neurons or glial cells was quantified in each group, averaged and subjected to statistical comparisons. Results: In the control group the number of nervous cells expressing apostain was 138 ± 16, at the 8 hours and 82 ± 13 at the 72 hours after lesion. In the treated group the number of nervous cells expressing apostain was 76 ± 11, at the 8 hours, and 57 ± 7, at the 72 hours with statistically significant differences between the experimental groups. Conclusions: The intralesional administration of mesenchymal stem cells exercises an antiapoptotic effect in the precocious phases after severe SCI (AU)

Angiogénesis y vasculogénesis inducida por el trasplante intralesional de células madre mesenquimales adultas en un modelo experimental de daño medular traumático / Angiogenesis and vasculogenesis induced by intralesional adult mesenchymal stem cell transplantation in an experimental spinal cord injury model

Objetivos: Estudiar si las células madre adultas mesenquimales, del estroma de la médula ósea (BMSC) contribuyen a la angiogénesis y vasculogénesis, tras su trasplante intralesional en la médula espinal traumatizada. Material y métodos: Se utilizó un modelo de lesión traumática medular estandarizada, en ratas Wistar y en cerdos adultos. A los 3 meses del traumatismo medular, en situación de paraplejia completa, se administraron intralesionalmente 3 x 106 BMSC marcadas mediante transfección génica con el gen LacZ (en la rata) y 30 x 106 BMSC marcadas con BrdU (en el cerdo). A los 3 meses del trasplante se estudió la zona del implante celular para detectar la presencia de vasos sanguíneos formados a expensas de las células trasplantadas. Resultados: Tanto en la rata Wistar como en el cerdo, se observaron numerosos vasos sanguíneos con células a nivel endotelial y en la pared del vaso que expresaban los marcadores propios de las células trasplantadas. Conclusiones: Las BMSC se pueden diferenciar in vivo hacia células endoteliales y hacia células musculares lisas, tras su trasplante intralesional en la médula espinal traumatizada, formando parte de nuevos vasos sanguíneos y contribuyendo a los fenómenos de angiogénesis y vasculogénesis necesarios para la regeneración del tejido nervioso lesionado (AU)

Objectives: To determine whether adult mesenchymal stem cells (bone marrow stromal cells, BMSCs) contribute to angiogenesis and vasculogenesis following their intralesional implantation in the damaged spinal cord. Material and methods: A standard spinal cord injury model was used in Wistar rats and adult pigs. Three months after spinal cord injury, under conditions of complete paraplegia, 3 x 106 BMSCs labeled via genic transfection with the LacZ gene (in rats), and 30 x 106 BMSCs labeled with BrdU (in pigs), were administered in the spinal lesion zone. Three months after implantation, the cell implant zone was studied to detect the presence of blood vessels formed at the expense of the transplanted cells. Results: In both the Wistar rats and pigs, numerous blood vessels were observed, with cells at endothelial level and in the vessel wall that expressed the markers inherent to the transplanted cells. Conclusions: BMSCs can differentiate under in vivo conditions towards endothelial cells and towards smooth muscle cells, following their intralesional transplantation in the damaged spinal cord – forming part of new blood vessels and contributing to the angiogenesis and vasculogenesis required for regeneration of the damaged nerve tissue (AU)

Diferenciación neural de células del estroma de médula ósea humana en presencia de líquido cefalorraquídeo / Neural differentiation of human bone marrow stromal cells in the presence of cerebrospinal fluid

Objetivo: Analizar la influencia del LCR sobre el proceso de diferenciación neural de BMSC inducida por agentes químicos. Material y métodos: Se hizo un estudio de diferenciación química de BMSC humanas, valorando el porcentaje de ellas que expresan marcadores neurales, a diferentes tiempos tras ser expuestas in vitro a factores químicos de inducción neuronal, y se ha comparado este proceso de transdiferenciación morfológica con el obtenido tras repetir el estudio en las mismas condiciones experimentales, pero añadiendo al medio de cultivo 1 ml de LCR, con una concentración de factor neurotrófico derivado de cerebro (BDNF) de 1,5 pg/ml. Resultados: Los factores neurotróficos presentes en LCR, en las condiciones experimentales del presente estudio, no modifican el proceso de diferenciación neural de BMSC mediado in vitro por agentes químicos. Conclusiones: Este hallazgo sugiere que cuando las BMSC son administradas en el espacio subaracnoideo, los factores neurotróficos del LCR no influyen significativamente en el proceso de su diferenciación neural (AU)

Objective: To analyze the influence of cerebrospinal fluid (CSF) upon the neural differentiation of bone marrow stromal cells (BMSCs) induced by chemical agents. Material and methods: A chemical differentiation study was made of human BMSCs, assessing the percentage of the latter that express neural markers at different timepoints following in vitro exposure to chemical neural induction factors. This morphological trans-differentiation process was in turn compared with that obtained after repeating the study under the same conditions but adding 1 ml of CSF to the culture medium, with a brain derived neurotrophic factor (BDNF) concentration of 1.5 pg/ml. Results: Under the experimental conditions of this study, the neurotrophic factors present in CSF did not modify the neural differentiation process of BMSCs mediated by chemical agents in vitro. Conclusions: These findings suggest that when BMSCs are administered within the subarachnoid space, the neurotrophic factors in CSF do not significantly influence the neural differentiation of the cells (AU)

Metals in the surface sediments of Istanbul Strait (Turkey).

Surface sediments from 17 stations in the Istanbul Strait and Marmara Sea were collected and analysed for major and trace elements by wavelength-dispersive X-ray fluorescence spectrometry (WDXRF). Metal concentrations in surface sediments varied from 1.3 to 7.2 % for Al, 4.8 to 18 mg kg(- 1) for As, 119 to 599 mg kg(- 1) for Ba, below detection limit (bdl) to 6.6 mg kg(- 1) for Cd, 18 to 222 mg kg(- 1) for Cr, 7.6 to 180 mg kg(- 1) for Cu, 1.0 to 5.5 % for Fe (10 000 to 55 000 mg kg(- 1)), 171 to 718 mg kg(- 1)for Mn, 3.3 to 64 mg kg(- 1) for Ni, 4.5 to 461 mg kg(- 1) for Pb, 1.3 to 68 mg kg(- 1) for Sn, 19 to 170 mg kg(- 1) for V and 16 to 859 mg kg(- 1) for Zn. Three tools have been applied in order to evaluate metal pollution in the sediments; Sediment quality guidelines (SQGs), enrichment factors (EFs) and geoaccumulation index (I(geo)). SQGs values indicate that Pb and Ni are the most likely contaminants to cause adverse biological effects. On the other hand, both metal enrichment factors and geoaccumulation index show that As, Zn, Pb and Cd contaminations exist in the entire study area and contamination of other metals is also present in some sites depending on the sources. Factor analysis (FA) receptor modelling technique was applied to investigate the sources affecting surface sediment samples at the Istanbul Strait.

Bioconcentration and phototoxicity of selected PAHs to marine mussel Mytilus galloprovincialis.

This study assessed the sensitivity of Mytilus galloprovincialis (Mediterranean mussel) to UV-induced toxicity of pyrene, phenanthrene, fluoranthene and chrysene. Mussels were exposed to two different polyaromatic hydrocarbon (PAH) concentrations within the solubility limits for 7 days, after which the filtration rate and the blood cell stability of the mussels were determined to quantify the effects of PAHs. Mussel tissues were analysed at the end of the experiments to determine the degree of bioaccumulation of PAHs and in order to make quantitative body-burden/effect links. The differences between the tissue residue based effective concentration (TEC(20)/TEC(50)) values before and after ultraviolet (UV) exposure provided a measure of phototoxicity of the bioaccumulated PAHs. Out off the biomarkers applied, Neutral Red Retention (NRR) results showed that the most toxic compound is chrysene in the absence of UV. The NRR technique was found more sensitive compared to Fitration Rate (FR) technique. The toxicities of chrysene, phenanthrene and pyrene were enhanced by UV, while fluoranthene was toxic in the absence of UV lighting and its toxicity did not change by UV application.

Estudio morfológico de la neurocarcinogénesis experimental inducida por nitroso-ureas / Morphological study of the experimental neurocarcinogenesis induced by nitrosoureas

En el presente trabajo se hace una revisión de la neurocarcinogénesis química,con especial referencia a los tumores del Sistema Nervioso inducidos por etil-nitrosoureaen la rata Wistar. El estudio morfológico de los tumores del Sistema NerviosoCentral y del Sistema Nervioso Periférico inducidos por exposición prenatala este carcinógeno (50 mg/kg día 17 de gestación) muestra la aparición de tumorescompatibles con un diagnóstico histológico de schwannoma maligno o de oligodendroglioma.Sin embargo, los estudios inmunohistoquímicos y ultraestructuralespermiten clasificar a estos tumores, independientemente de su morfología, comotumores malignos, de tipo neuroectodérmico indiferenciado, con posibilidad dediferenciación hacia líneas neuronales y gliales. Sus características biológicas y suposible diagnóstico in vivo, por medio de Resonancia Magnética, hacen que estemodelo de neurocarcinogénesis sea extraordinariamente útil para valorar el efectode nuevos tratamientos farmacológicos, aplicables a tumores cerebrales malignosen el hombre

This work shows a revision of the chemical neurocarcinogenesis, with specialreference to the Nervous System tumors induced by ethyl-nitrosourea in the Wistarrat. Prenatal administration of this carcinogen (50 mg/kg, day 17 of pregnancy)induces Nervous System tumors with histological features of malignantschwannomas or oligodendrogliomas. However, and independently of theirmorphology, the immunohistochemical and ultrastructural studies allow to classifyto these tumors as undifferentiated malignant tumors, with tumor cells showingpossible differentiation toward neuronal and glial phenotypes. Their biologicproperties and their possible diagnosis in vivo, by means of Magnetic Resonance,make this neurocarcinogenesis model to be extraordinarily useful to value theeffect of new drug treatments, applicable to human malignant brain tumors

Implicación de factores neurotróficos en la transdiferenciación neuronal de células madre mesenquimales adultas / Implication of neurotrophic factors in the neuronal transdifferentiation of adult mesenchymal stem cells

Introducción: En los últimos años se están recogiendo evidencias a favor de que, en determinadas condiciones experimentales, pueda tener lugar un proceso de transdiferenciación de células madre (CM) adultas mesenquimales hacia células nerviosas. La observación de que la presencia de células de Schwann produce la transdiferenciación neuronal de CM mesenquimales obtenidas del estroma de la médula ósea ha motivado la realización del presente estudio, con la finalidad de conocer la implicación de factores neurotróficos en el proceso de diferenciación neuronal de estas células. Material y métodos: En este trabajo hemos cultivado CM mesenquimales adultas, del estroma de médula ósea, añadiendo al medio de cultivo Factor neurotrófico recombinante derivado de cerebro (BDNF, 10 ng/ml), Factor de crecimiento nervioso (NGF 7S, 10 ng/ml) y Ácido retinoico (5 μg/ml). El porcentaje de células que muestran morfología neuronal y expresan PNF (200 Kd) fue valorado a los 2, 7 y 14 días. A efectos comparativos se utilizaron datos de un estudio previo de transdiferenciación de CM por medio de beta-mercaptoetanol y por medio de su co-cultivo con células de Schwann. Resultados: Los resultados mostraron que tanto el NGF como el BDNF, a las concentraciones utilizadas, son capaces de lograr transdiferenciación de las CM mesenquimales adultas hacia una morfología neuronal, con un porcentaje de CM transdiferenciadas, entre los 7 y 14 días de tratamiento, similar al que se obtiene cultivando CM en presencia de células de Schwann. Conclusiones: Los hallazgos obtenidos sugieren que los fenómenos de transdiferenciación neuronal in vivo, cuando las CM mesenquimales adultas se implantan en el Sistema Nervioso, están principalmente mediados por factores neurotróficos locales, por lo que puede ser innecesario plantear una transdiferenciación neuronal in vitro de las CM adultas en protocolos de terapia celular para el tratamiento de lesiones neurológicas

Introduction: Recently has been reported that under certain experimental conditions, adult mesenchymal stem cells (SC) show neuronal transdifferentiation. The observation that the presence of Schwann cells promotes neuronal transdifferentiation of bone marrow stromal SC has motivated the realization of the present study, with the purpose of knowing the possible implication of neurotrophic factors in this process. Material and methods: We have cultured adult mesenchymal SC obtained from the stroma of the bone marrow, adding to the cultures recombinant Brain derived neurotrophic factor (BDNF, 10 ng/ml)), Nervous growth factor (NGF 7S, 10 ng/ml) and retinoic acid (5 μg/ml). The percentage of cells showing neuronal morphology and expressing Neurofilament protein, (NFP, 200 Kd) was valued after 2, 7 and 14 days, and these data were compared with the data obtained in a previous study carrying out SC transdifferentiation by beta-mercaptoethanol or culturing adult mesenchymal SC in presence of Schwann cells. Results: The results show that NGF and BDNF are neurotrophic factors able to achieve neuronal transdifferentiation of adult mesenchymal SC, with a percentage of SC showing neuronal morphology similar to which is obtained using beta-mercaptoethanol or Schwann cells. Conclusions: These findings suggest that neuronal transdifferentiation obtained in vivo, when adult mesenchymal SC are implanted in the Nervous System, may be mainly related with the local presence of neurotrophic factors. Thus, is questionable the necessity of proceeding in vitro to a neuronal transdifferentiation of adult SC, as a previous step, when local administration of adult SC is considered for the treatment of System Nervous lesions