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Andean ecosystems are characterized by high humidity, mainly from rain and fog events. Because of differences in altitude two Andean ecosystems - sub-Andean forest and Páramo -face different environmental pressures that affect leaf anatomy and cell wall composition and, consequently, species foliar water uptake (FWU) capacity. Here, FWU capacity of eight species in the Melastomataceae was evaluated and found to be related to proportions of cell wall components and aquaporins in the two ecosystems. Cellulose was labelled with Calcofluor white, and aquaporin and pectins were labelled with monoclonal antibodies. There were differences in plant FWU capacity in both ecosystems, with higher FWU capacity in sub-Andean forest species than in Páramo forest species. Cell wall components were positively related to FWU, with increased FWU related to pectin and aquaporin content of the plasma membrane. Differences in water availability in the two analysed environments led to differences in FWU capacity that are associated with leaf anatomical traits and cell wall composition. In these two environments, plants with similar traits are selected to respond to given environmental pressures. Traits that favour FWU in sub-Andean forest species may lead to further advances of these species in this environments.

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The Madín Dam is a reservoir located in the municipalities of Naucalpan and Atizapán, in the metropolitan area adjacent to Mexico City. The reservoir supplies drinking water to nearby communities and provides an area for various recreational activities, including kayaking, sailing and carp fishing. Over time, the number of specimens of common carp has notably diminished in the reservoir, which receives direct domestic drainage from two towns as well as numerous neighborhoods along the Tlalnepantla River. Diverse studies have demonstrated that the pollutants in the water of the reservoir produce oxidative stress, genotoxicity and cytotoxicity in juvenile Cyprinus carpio, possibly explaining the reduction in the population of this species; however, it is necessary to assess whether these effects may also be occurring directly in the embryos. Hence, surface water samples were taken at five sites and pharmaceutical drugs, personal care products (especially sunscreens), organophosphate and organochlorine pesticides, and other persistent organic pollutants (e.g., polychlorinated biphenyls and polycyclic aromatic hydrocarbons) were identified. Embryos of C. carpio were exposed to the water samples to evaluate embryolethality, modifications in embryonic development, lipoperoxidation, the quantity of hydroperoxide and oxidized proteins, and antioxidant enzyme activity (superoxide dismutase, catalase and glutathione peroxidase). It was found that the polluted water of the Madín Dam gave rise to embryolethality, embryotoxicity, congenital abnormalities, and oxidative stress on the common carp embryos.

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Uterine acute post-breeding inflammation is a physiological tissue response to the entry of exogenous elements, with persistent endometritis being the main pathology responsible for subfertility in the mare (Equus ferus caballus; Linnaeus, 1758). Mares can be classified as susceptible or resistant to endometritis according to their ability to remove intrauterine fluid within 48 hr after experimental inoculation. Endometrial biopsy is a technique that is commonly used to establish the degree of lesions that can affect the fertility of the mare. Endometrial histomorphometry is an objective and highly precise diagnostic method. The aim of this study was to compare, during oestrus, the endometrial histomorphometry of mares previously classified as susceptible (SM) or resistant (RM) to endometritis. Endometrial biopsies from 24 mares at the oestrus phase of the cycle were obtained. For the histomorphometric analysis, samples were histologically processed and subjected to routine Haematoxylin-Eosin staining. For the evaluation, the variables were considered as follows: 1-Height of the lining and glandular epithelia (Lining SM = 15.9 µm vs. RM = 13.3 µm; Glandular SM = 15.0 µm vs. RM = 13.0 µm); 2-Perpendicular diameters of endometrial glands (SM = 51.3 µm vs. RM = 44.8 µm); 3-Number of endometrial glands per field (SM = 24.8 glands/field vs. RM = 20.5 glands/field). The results from this study suggest the existence of a relationship between the studied characteristics and the susceptibility/resistance to post-breeding endometritis in mares. Thus, increased epithelial height, greater glandular density and greater development of the glands during oestrus would be related to a higher susceptibility to endometritis.

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The electronic transport properties of ordered networks using carbon nanotubes as building blocks (ON-CNTs) are investigated within the framework of a multiterminal Landauer-Buttiker formalism using an s,p(x),p(y),p(z) parameterization of the tight-binding Hamiltonian for carbon. The networks exhibit electron pathway selectiveness, which is shown to depend on the atomic structure of the network nodes imposed by the specific architecture of the network and the distribution of its defects (non-hexagonal rings). This work represents the first understandings towards leading current through well-defined trajectories along an organic nanocircuit.

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Among 23 pediatric patients who underwent orthotopic liver transplant (OLT), we report two (11 and 26 months old) with posttransplant lymphoproliferative disease (PTLD) that occurred in the early posttransplantation period. They were Epstein-Barr Virus (EBV)-negative and received graft from EBV-positive donors. The surveillance for EBV viremia using serial EBV polymerase chain reaction determinations in the peripheral blood was positive at 10 and 90 days after OLT concomitant with symptoms of primary infection, both patients were treated with gancyclovir. The patients should progression to a Burkitt's and a non-Hodgkin's lymphoma that appeared 3 months posttransplantation. They were treated by withdrawal of immunosuppression and six courses of cyclophosphamide as well as anti-CD20 monoclonal antibody (Rituximab) every 21 days. One patient experienced acute graft rejection, which resolved with steroids and low doses of tacrolimus, she is free of disease at 24 months after the end of treatment. The other patient relapsed with a cerebral lymphoma, receiving aggressive chemotherapy, but died due to sepsis. In conclusion, PTLD occurred among in 2/23 patients who underwent OLT and appeared in the first quarter post OLT. The risk factors associated with early PTLD were primary EBV infection after OLT, young age, and EBV-negative recipient receiving a transplant from an EBV-positive donor. Antiviral treatment alone was inefficient; withdrawal of immunosuppression and courses of Rituximab and cyclophosphamide were well tolerated and controlled PTLD. The risk of graft rejection was increased by withdrawal of immunosuppression. One patient died.

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El teratoma sacrococcígeo (TS) es una malformación de muy baja frecuencia y de alta letalidad. El objetivo de este trabajo es presentar un caso clínico de diagnóstico prenatal de teratoma sacrococcígeo, utilizando ultrasonido y resonancia magnética. Paciente de 21 semanas de gestación es enviada para segunda opinión a nuestro centro. Realizamos examen ultrasonográfico que reveló una lesión perineal quística predominante externa de gran tamaño, con componente presacro de menor volumen y escasos vasos sanguíneos en su pared, lo que sugiere el diagnóstico de teratoma quístico. Se realiza resonancia magnética que comprueba el diagnóstico de TS quístico predominantemente externo. El resto de la evaluación anatómica y hemodinámica fue normal. Evoluciona con aumento del tamaño de la lesión, sin complicaciones maternas o fetales. A las 38 semanas de gestación, se realiza operación cesárea que comprueba diagnóstico de TS, y a las 24 horas de vida se efectúa extirpación del tumor en su totalidad con resección del cóccix y parte del sacro, con plastía del defecto remanente. El diagnóstico prenatal de TS quístico, en nuestro caso, mediante el uso de ultrasonido y resonancia magnética permite por una parte predecir una evolución favorable durante la gestación, y por otra, posibilita el manejo multidisciplinario con interrupción programada y cirugía definitiva del TS.

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Pediatric solid tumors represent a distinct set of malignancies of embryonal origin whose incidence peaks in the first years of life. Specific genetic anomalies with pathogenic significance, which have helped to define the diagnosis better and to improve the prognosis of children with these tumors, recently have been discovered. Survival of children with solid tumors also has improved significantly because of effective multidisciplinary care, which, in this case, always involves chemotherapy and surgery. These favorable results require that children with these diseases are referred and treated at institutions that have multidisciplinary teams and the infrastructure and expertise for caring for these children. Diagnostic and therapeutic principles for the most common childhood solid tumors are discussed in this article, with an emphasis on surgical procedures.

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BACKGROUND: Malignant hepatic tumors (Mht) are rare in children. Among them hepatoblastoma (HB) is the most common. AIM: To report the results of the multidisciplinary management in 6 consecutive children: five HB and one metastatic Wilms tumor (MWT). PATIENTS AND METHODS: The mean age of patients was 42 months. All HB patients had elevated serum alfafetoprotein (median 150,000 ng/ml). All patients received preoperative chemotherapy: HB patients received carboplatin/doxorubicin alternating with cisplatin, and the MWT patient, vincristine alone. Surgery included two formal right and two formal left hepatectomies, one extensive central resection with partial left segmentectomy, and one lateral segmentectomy. Extracorporeal circulation was used in the child with atrial involvement. All patients received postoperative chemotherapy. RESULTS: All tumors had variable regresion on preoperative chemotherapy. Complete resection with negative margins was achieved in all patients. The degree of tumor necrosis on histology ranged from 60% to 90%. Alfafetoprotein levels fell to under 10 ng/ml in all HB cases, one to three months after surgery. All patients survive free of disease at a median follow up of 19 months. CONCLUSION: A multidisciplinary approach including the well timed used of chemotherapy and surgery is highly effective in the management of pediatric malignant tumors.

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En este articulo se comparan diferentes metodos de cultivo de medula osea de raton para demostrar las celulas formadoras de colonias de macrofagos y granulocitos (CFCmg). Se uso medio McCoy 5A complementado con diferentes proporciones de suero fetal de ternera (SFT) y suero de caballo (SC), y se compararon el sistema de cultivo en nonocapa y doble capa y tres fuentes de factor estimulante de colonias de macrofagos y granulocitos (FECmg): capa trofica de fibroblastos L-929, suero postoxoide difterico (SPTD) y medio condicionado L preparado con McCoy (MCL-McCoy) o Eagle (MCL-MEM). Se probaron como complementos L-asparagina, albumina bovina y mercaptoetanol. Los mejores resultados se obtuvieron con McCoy complementado con 10 por ciento de SFT y 5 por ciento de SC y como FECmg, MCL-MEM. La adicion de complementos no mejoro el numero o el tamano de las colonias, concluyendo que el FECmg y os sueros son los factores criticos en la proliferacion in vitro de las CFCmg

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