Intestinal neuroendocrine tumor in a patient with pituitary adenoma. A case report and review of the current screening recommendations

<p>Abstract</p> <p>Introduction</p> <p>Multiple endocrine neoplasia type 1 (MEN-1) patients are prone to develop carcinoid tumors. Few cases report the development of gastrointestinal carcinoid tumors in patients with MEN-1 syndrome related tumors. This is the first paper to report the occurrence of an intestinal carcinoid tumour in association with a pituitary adenoma.</p> <p>Case presentation</p> <p>A <b>s</b>ixty eight year old female presented with intestinal obstruction four years after transphenoidal pituitary resection for pituitary adenoma. During surgical exploration and lysis of adhesions, we accidentally discovered an intestinal carcinoid tumour. Resection of the involved small bowel segment and the draining lymph nodes was undertaken. Postoperative follow up showed no biochemical or radiological evidence of residual tumor.</p> <p>Neuroendocrine tumors (NETs) may occur as part of familial endocrine cancer syndromes including MEN-1. It is recommended that clinicians search thoroughly for MEN-1 in patients presented with NETs, however, there is no current consensus for screening patients suspected to have MEN-1 to rule out NET.</p> <p>Conclusion</p> <p>We recommend screening patients suspected to have any familial type of endocrine tumors for the presence of NET.</p

Diseño de la metodología para determinar caudales característicos mensuales multianuales en una cuenca rural no instrumentada a través del programa HEC-HMS

Trabajo de gradoEl trabajo de grado tiene como objetivo determinar los caudales característicos mensuales multianuales en una cuenca no instrumentada a través del programa HEC-HMS. La cuenca objeto de estudio corresponde al caño Dumacita, afluente directo del río Cusiana ubicada en el municipio de Maní, en el departamento del Casanare. Para desarrollar el análisis de caudales característicos se trabajará con información meteorológica proporcionada por el Instituto de Hidrología, Meteorología y Estudios Ambientales – IDEAM e información morfométrica, tipo de suelos y coberturas de la tierra de la microcuenca, provenientes del Estudio de impacto ambiental fase de explotación Campo Puntero, elaborado por la empresa Auditoria Ambiental S.A.S. durante el año 2014, donde se pudo establecer de manera satisfactoria la estimación del régimen de caudales característicos del caño Dumacita.EspecializaciónEspecialista en Recursos Hídrico

Sustainable Water Management in the Southwestern United States: Reality or Rhetoric?

Background: While freshwater sustainability is generally defined as the provisioning of water for both people and the environment, in practice it is largely focused only on supplying water to furnish human population growth. Symptomatic of this is the state of Arizona, where rapid growth outside of the metropolitan Phoenix-Tucson corridor relies on the same groundwater that supplies year-round flow in rivers. Using Arizona as a case study, we present the first study in the southwestern United States that evaluates the potential impact of future population growth and water demand on streamflow depletion across multiple watersheds. Methodology/Principal Findings: We modeled population growth and water demand through 2050 and used four scenarios to explore the potential effects of alternative growth and water management strategies on river flows. Under the base population projection, we found that rivers in seven of the 18 study watersheds could be dewatered due to municipal demand. Implementing alternative growth and water management strategies, however, could prevent four of these rivers from being dewatered. Conclusions/Significance: The window of opportunity to implement water management strategies is narrowing. Because impacts from groundwater extraction are cumulative and cannot be immediately reversed, proactive water management strategies should be implemented where groundwater will be used to support new municipal demand. Our approach provides a low-cost method to identify where alternative water and growth management strategies may have the most impact, and demonstrates that such strategies can maintain a continued water supply for both people and the environment

Using CFD as a Rocket Injector Design Tool: Recent Progress at Marshall Space Flight Center

New programs are forcing American propulsion system designers into unfamiliar territory. For instance, industry s answer to the cost and reliability goals set out by the Next Generation Launch Technology Program are engine concepts based on the Oxygen- Rich Staged Combustion Cycle. Historical injector design tools are not well suited for this new task. The empirical correlations do not apply directly to the injector concepts associated with the ORSC cycle. These legacy tools focus primarily on performance with environment evaluation a secondary objective. Additionally, the environmental capability of these tools is usually one-dimensional while the actual environments are at least two- and often three-dimensional. CFD has the potential to calculate performance and multi-dimensional environments but its use in the injector design process has been retarded by long solution turnaround times and insufficient demonstrated accuracy. This paper has documented the parallel paths of program support and technology development currently employed at Marshall Space Flight Center in an effort to move CFD to the forefront of injector design. MSFC has established a long-term goal for use of CFD for combustion devices design. The work on injector design is the heart of that vision and the Combustion Devices CFD Simulation Capability Roadmap that focuses the vision. The SRL concept, combining solution fidelity, robustness and accuracy, has been established as a quantitative gauge of current and desired capability. Three examples of current injector analysis for program support have been presented and discussed. These examples are used to establish the current capability at MSFC for these problems. Shortcomings identified from this experience are being used as inputs to the Roadmap process. The SRL evaluation identified lack of demonstrated solution accuracy as a major issue. Accordingly, the MSFC view of code validation and current MSFC-funded validation efforts were discussed in some detail. The objectives of each effort were noted. Issues relative to code validation for injector design were discussed in some detail. The requirement for CFD support during the design of the experiment was noted and discussed in terms of instrumentation placement and experimental rig uncertainty. In conclusion, MSFC has made significant progress in the last two years in advancing CFD toward the goal of application to injector design. A parallel effort focused on program support and technology development via the SCIT Task have enabled the progress

Architecture and Selectivity in Aquaporins: 2.5 Å X-Ray Structure of Aquaporin Z

Aquaporins are a family of water and small molecule channels found in organisms ranging from bacteria to animals. One of these channels, the E. coli protein aquaporin Z (AqpZ), has been shown to selectively conduct only water at high rates. We have expressed, purified, crystallized, and solved the X-ray structure of AqpZ. The 2.5 Å resolution structure of AqpZ suggests aquaporin selectivity results both from a steric mechanism due to pore size and from specific amino acid substitutions that regulate the preference for a hydrophobic or hydrophilic substrate. This structure provides direct evidence on the molecular mechanisms of specificity between water and glycerol in this family of channels from a single species. It is to our knowledge the first atomic resolution structure of a recombinant aquaporin and so provides a platform for combined genetic, mutational, functional, and structural determinations of the mechanisms of aquaporins and, more generally, the assembly of multimeric membrane proteins

Cellular Metabolites Enhance the Light Sensitivity of Arabidopsis Cryptochrome through Alternate Electron Transfer Pathways

Cryptochromes are blue light receptors with multiple signaling roles in plants and animals. Plant cryptochrome (cry1 and cry2) biological activity has been linked to flavin photoreduction via an electron transport chain comprising three evolutionarily conserved tryptophan residues known as the Trp triad. Recently, it has been reported that cry2 Trp triad mutants, which fail to undergo photoreduction in vitro, nonetheless show biological activity in vivo, raising the possibility of alternate signaling pathways. Here, we show that Arabidopsis thaliana cry2 proteins containing Trp triad mutations indeed undergo robust photoreduction in living cultured insect cells. UV/Vis and electron paramagnetic resonance spectroscopy resolves the discrepancy between in vivo and in vitro photochemical activity, as small metabolites, including NADPH, NADH, and ATP, were found to promote cry photoreduction even in mutants lacking the classic Trp triad electron transfer chain. These metabolites facilitate alternate electron transfer pathways and increase light-induced radical pair formation. We conclude that cryptochrome activation is consistent with a mechanism of light-induced electron transfer followed by flavin photoreduction in vivo. We further conclude that in vivo modulation by cellular compounds represents a feature of the cryptochrome signaling mechanism that has important consequences for light responsivity and activation

Effects of climate variability and accelerated forest thinning on watershed-scale runoff in southwestern USA ponderosa pine forests

The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0–3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide

Estudio de la inundabilidad de la confluencia quebrada Avendaño con el río Moche

La presente tesis tiene como objetivo realizar el estudio de inundabilidad en la confluencia del río Moche y la quebrada Avendaño, además estimar el transporte de sedimentos de fondo, para ello se realizó un estudio topográfico con estación total y drone, obteniendo como resultado una pendiente de 1.78% para el río Moche y una pendiente de 1.81% para la quebrada Avendaño. Así mismo se realizó el estudio hidrológico para ello se usó la data de los caudales (1950 al 2017) y precipitaciones diarias acumuladas proporcionados por la Gerencia Regional de Agricultura de la región La Libertad y el ANA respectivamente; con el registro hidrológico se calculó los caudales de máximas avenidas de 328.27m³/s, 479.81m³/s, 620.97m³/s, 789.13m³/s, 1059.84m³/s para períodos de retorno de 20, 50, 100, 200 y 500 años respectivamente, mientras que para la quebrada Avendaño se obtuvieron caudales de máximas avenidas de 62.08 m³/s, 79.61m³/s, 92.81m³/s, 103.56 m³/s, 123.39m³/s para períodos de retorno de 20, 50, 100, 200 y 500 años respectivamente. Se realizó el estudio de granulometría obteniendo como resultados para el material de fondo del río Moche un d50 de 17mm (Grava gruesa) y para la quebrada Avendaño un d50 de 10.76mm (Grava media). Se realizó el modelamiento hidráulico mediante el software Iber 2.5.1 para realizar el estudio de inundabilidad y determinar las áreas críticas en la confluencia del río Moche y la quebrada. Se diseñaron los diques con enrocado con el caudal de máxima avenida de 620.97m³/s para un periodo de retorno de 100 años para el río Moche obteniendo como resultados: ancho de corona de 4m, altura de dique de 3m, diámetro de la roca 1.20 m. Mediante el software Iber 2.5.1, se analizó el transporte de sedimentos de fondo en la confluencia del río Moche y la quebrada Avendaño para los diferentes caudales de máximas avenidas en dos escenarios (sin diques y con diques); para el modelo sin diques el transporte de sedimentos que se estimó fue de 3.45 ton/s, 3.71 ton/s, 6,31 ton/s, 7.61 ton/s y 9.09 ton/s para períodos de retorno de 20, 50, 100, 200 y 500 años respectivamente. Mientras que para el escenario con diques el transporte de sedimentos que estimó fue de 2.25 ton/s, 3.58 ton/s, 5.19 ton/s, 6.49 ton/s y 7.42 ton/s para períodos de retorno de 20, 50, 100, 200 y 500 años respectivamente.The objective of this thesis is to carry out the study of flooding at the confluence of the Moche river and the Avendaño creek, in addition to estimating the transport of bottom sediments, for this a topographic study was carried out with a total station and drone, obtaining as a result a slope of 1.78% for the Moche River and a slope of 1.81% for the Avendaño stream. Likewise, the hydrological study was carried out for this, the data of the flows (1950 to 2017) and accumulated daily rainfall provided by the Regional Management of Agriculture of the La Libertad region and the ANA respectively were used; With the hydrological record, the maximum flood flows of 328.27m³ / s, 479.81m³ / s, 620.97m³ / s, 789.13m³ / s, 1059.84m³ / s were calculated for return periods of 20, 50, 100, 200 and 500 years respectively, while for the Avendaño stream, maximum flood flows of 62.08 m³ / s, 79.61m³ / s, 92.81m³ / s, 103.56 m³ / s, 123.39m³ / s were obtained for return periods of 20, 50, 100 , 200 and 500 years respectively. The granulometry study was carried out, obtaining as results for the bottom material of the Moche river a d50 of 17mm (Coarse gravel) and for the Avendaño stream a d50 of 10.76mm (Medium gravel). The hydraulic mode was carried out using Iber 2.5.1 software to carry out the flood study and determine the critical areas at the confluence of the Moche River and the stream. The rock walls were designed with a maximum avenue flow of 620.97m³ / s for a return period of 100 years for the Moche River, obtaining as results: crown width of 4m, height of the dike of 3m, diameter of the rock 1.20 meter. Using Iber 2.5.1 software, the transport of bottom sediments at the confluence of the Moche River and the Avendaño stream was analyzed for the different flows of maximum avenues in two scenarios (without dikes and with dikes); for the model without dikes, the sediment transport that was estimated was 3.45 ton/s, 3.71 ton/s, 6,31 ton/s, 7.61 ton/s y 9.09 ton/s for return periods of 20, 50, 100, 200 and 500 years respectively. While for the scenario with dikes, the sediment transport that he estimated was 2.25 ton/s, 3.58 ton/s, 5.19 ton/s, 6.49 ton/s y 7.42 ton/s for return periods of 20, 50, 100, 200 and 500 years respectively.Tesi