Comparative long-term evaluation of tacrolimus and cyclosporine in pediatric liver transplantation

Background. In this report, we compare the long-term outcome of pediatric liver transplantation (LTx) patients maintained with tacrolimus-based and with cyclosporine (CsA)-based immunosuppressive therapy. We examine long-term patient and graft survival, the incidence of rejection, and immunosuppression-related complications. Method. There were 233 consecutive primary LTx in children (ages <18 years) performed between October 1989 and December 1994 with tacrolimus-based immunosuppressive therapy (Group I). These were compared with 120 consecutive primary LTx performed with CsA-based immunosuppressive therapy between January 1988 and October 1989(Group II). Children in both groups were followed until July 1999. Mean follow-up was 91.41±17.7 months (range 55.6-117.8) for Group I, and 128±6.1 months (range 116.7-138.6) for Group II. Results. At 9 years of follow-up, actuarial patient and graft survival were significantly improved (patient survival 85.4% in Group I vs. 63.8% in Group II, P=0.0001; graft survival Group I 78.9% vs. 60.8% Group II, P=0.0003) and the rate of re -transplantation was significantly lower among patients in Group I (12% in Group I vs. 22.5% in Group II P=0.01). Children in Group I also experienced a significantly reduced incidence of acute rejection (0.97 per patient Group I vs. 1.5 per patient Group II P=0.002) and significantly less steroid resistant acute rejection episodes (3.1% in Group I vs. 8.6% in Group II P=0.0001). The mean steroid dose was significantly lower in Group I compared with Group II at all time points (P=0.0001) after LTx. Freedom from steroid was also significantly higher in Group I compared with Group H at all time points after LTx (ranging from 78% to 84% in Group I and 9% to 32% in Group H during a 1- to 7-year posttransplant period P=0.0001). The rate of hypertension was significantly lower in Group I than Group II (P=0.0001), and the severity of hypertension (need for more than one anti-hypertensive medication) was also significantly lower in Group I than Group II (P=0.0001). Although the rate of posttransplant lymphoproliferative disorder (PTLD) was not significantly different (13.7% Group I vs.8.3% Group II, P=0.13), the survival after PTLD was significantly better for Group I at 81.2% than for Group II at 50% after 5 years (P=0.034). Conclusion. The results suggest that tacrolimus-based therapy provides significant long-term benefit to pediatric LTx patients, evidenced by significantly improved patient and graft survival, reduced rate of rejection, and hypertension with lower steroid doses

Precipitation and grain growth modelling in Ti-Nb microalloyed steels

Peer ReviewedPostprint (author's final draft

Detecting Stress in Glasshouse Plants Using Color Infrared Imagery: A Potential New Application for Remote Sensing

English: Studies were conducted to evaluate the effectiveness of color infrared (CIR) film for detecting physiological stress in plants located within glasshouse structures. Spectroradiometer measurements obtained within and outside of a structure constructed of polycarbonate plastic indicated no significant attenuation or disruption of visible and near-infrared radiation entering the structure. CIR photographs of cucumber seedlings (Cucumis sativus) obtained within the greenhouse were comparable in quality to those obtained outside the structure, and clearly distinguished between foliage of healthy plants and those subjected to a moderate level of nitrogen stress. In CIR imagery of a trifoliate orange tree (Poncirus trifoliata (L.) Raf.) obtained within a greenhouse constructed of yellow fiberglass panels, leaves damaged by citrus red mites (Panonychus citri [McGregor]) were distinguishable from healthy foliage, and the distribution of damaged leaves on the tree itself was clearly evident. These results suggest that remote sensing techniques which have been used successfully to monitor conventional field crops are readily extendable to the commercial glasshouse environment with certain modifications. Spanish: Se condujeron estudios para evaluar la eficacia de la película infrarroja de color (CIR) para detectar el estrés fisiológico en las plantas situadas dentro de un invernadero. Las mediciones del spectroradiómetro obtenidas dentro y fuera de un invernadero construido con plástico de policarbonato no indicaron ninguna atenuación o interrupción significativa de la radiación visible y del cercano infrarrojo que penetraba al invernadero. Las fotografías con CIR de las plantas de semillero de pepino (Cucumis sativus) obtenidas dentro del invernadero fueron comparables en calidad a aquellas obtenidas fuera de este, y distinguieron claramente entre el follaje de plantas sanas y de aquellas sometidas a un nivel moderado de estrés de nitrógeno. En imágenes de CIR de un naranjo trifoliado (Poncirus trifoliata (L.) Raf.) obtenidas dentro de un invernadero construido de paneles amarillos de fibra de vidrio, las hojas dañadas por el ácaro rojo de los cítricos (Panonychus citri [McGregor]) se distinguieron del follaje sano, y la distribución de hojas dañadas en el árbol mismo fueron claramente evidentes. Estos resultados sugieren que las técnicas de detección a distancia que se han utilizado con éxito para supervisar campos de cultivo convencionales, también pueden usarse fácilmente, con algunas modificaciones, en cultivos comerciales en invernadero

Design and development of complex phase steels with improved combination of strength and stretch-flangeability

This study presents the design and development of a hot-rolled bainitic steel, presenting a good combination of strength and stretch-flangeability, for automotive applications. Ti, Nb, and Mo were added in the steel composition in order to control austenite grain sizes, enhance precipitation hardening, and promote the formation of bainite. This study focuses on the effect of process parameters on final microstructures and mechanical properties. These parameters are the finishing rolling temperature, which conditions the austenite microstructure before its decomposition, and the coiling temperature, which conditions the nature and morphology of the ferritic phases transformed. A preliminary study allowed to determine the austenite grain growth behavior during reheating, the recrystallization kinetics, and the continuous cooling transformation curves of the studied steel. Then, a first set of parameters was tested at a semi-industrial scale, which confirmed that the best elongation properties were obtained for homogeneous bainitic lath/granular microstructures, that can be produced by choosing a coiling temperature of 500 °C . When choosing those parameters for the final industrial trial, the microstructure obtained consisted of a homogeneous lath/granular bainite mixture that presented a Ultimate Tensile Strength of 830 MPa and a Hole Expansion Ratio exceeding 70%.Peer ReviewedPostprint (published version

The Habitat Types of Freshwater Prawns (Palaemonidae: <em>Macrobrachium</em>) with Abbreviated Larval Development in Mesoamerica (Mexico, Guatemala and Belize)

The freshwater prawns of genus Macrobrachium with abbreviated larval development have been reported from a diversity of freshwater habitats (caves, springs and primary streams from so-long basins). Here we analysed 360 sites around the Mesoamerican region (Mexico, Guatemala and Belize). At each site, we measured temperature, salinity oxygen dissolved, pH, altitude and water flow velocity values. We documented the riparian vegetation and occurrence and abundance of Macrobrachium populations. All these values were analysed by multi-dimensional scaling and principal components analysis in order to identify key features of the environmental data that determine the habitat types and habitat diversity. The results show that there are Macrobrachium populations in 70 sites inhabiting two main habitats: Lotic and Lentic; and each one have fours subhabitat types. All are defined by altitude range and water velocity that involve the temperature and oxygen variables. In some specific areas, the karstic values on salinity and pH defined some groups. Within the lentic habitats, we identified the following subhabitats: (1) temperate streams, (2) neutral streams, (3) high dissolved oxygen, (4) multifactorial; and for lotic habitats, we identified: (5) water high carbonate, (6) moderate dissolved oxygen, (7) low dissolved oxygen, and (8) high altitude streams. All these subhabitats are located on the drainage basin to the Atlantic Sea, including places from 50 to 850 meters above sea levels and have specifically ranges from temperature, water velocity, pH and salinity for some cases. Also, the geological analysis from the basins where the Macrobrachium inhabit is located showed that the geological faults align with these habitat subdivisions. In this chapter, we discuss the environmental heterogeneity, morphological plasticity and their relationship to physiographic regions across the species ranges

Barriers to ideal outcomes after pediatric liver transplantation

Long‐term survival for children who undergo LT is now the rule rather than the exception. However, a focus on the outcome of patient or graft survival rates alone provides an incomplete and limited view of life for patients who undergo LT as an infant, child, or teen. The paradigm has now appropriately shifted to opportunities focused on our overarching goals of “surviving and thriving” with long‐term allograft health, freedom of complications from long‐term immunosuppression, self‐reported well‐being, and global functional health. Experts within the liver transplant community highlight clinical gaps and potential barriers at each of the pretransplant, intra‐operative, early‐, medium‐, and long‐term post‐transplant stages toward these broader mandates. Strategies including clinical research, innovation, and quality improvement targeting both traditional as well as PRO are outlined and, if successfully leveraged and conducted, would improve outcomes for recipients of pediatric LT.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151257/1/petr13537.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151257/2/petr13537_am.pd

Species richness under a vertebral stripe: integrative taxonomy uncovers three additional species of Pholidobolus lizards (Sauria, Squamata, Gymnophthalmidae) from the north-western Colombian Andes

The systematic study of biodiversity underlies appropriate inference in most other fields of biological research, yet it remains hampered by disagreements on both theoretical and empirical issues such as the species concept and the operational diagnosis of a species. Both become particularly challenging in those lineages where morphological traits are evolutionarily constrained by their adaptive value. For instance, cryptic organisms often conserve or converge in their external appearance, which hinders the recognition of species boundaries. An integrative approach has been adopted to study microgeographic variation in the leaf-litter lizard Pholidobolus vertebralis and test three predictions derived from the evolutionary species concept. Molecular data provided unambiguous evidence of divergence among the three recovered new clades and a common evolutionary history for each of them. The broadly sympatric clades were indeed diagnosable from externally visible traits, such as head scales, adult size, and sexually dimorphic ventral colouration. Also, they barely overlapped on the phenotypic space that summarised 39 morphometric and meristic traits. These clades are described as three species and an available name is suggested for a recovered fourth clade. The geographic distribution of the new and proximate species suggests a role for elevation on evolutionary divergence; it also raises interesting questions on the speciation pattern of an otherwise underestimated cryptic lineage