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Real-time reverse transcription quantitative PCR (RT-qPCR) is an important tool for gene expression analysis. Suitable reference genes are the basis of accurate and reliable RT-qPCR results. Litchi (Litchi chinensis Sonn.) is a commercially important tropical and subtropical fruit, but rapid pericarp browning is a substantial negative impact on its commercial use. Reference gene validation could help in the screening for genes involved in the browning mechanism. We assessed 15 new candidate reference genes from litchi transcriptome to determine stable reference genes for RT-qPCR analysis of pericarps from different cultivars, with differing postharvest storage, and under pathogenic stress. Ct values, geNorm, Normfinder, and RefFinder algorithms, were used to identify genes with the most stable transcription. GAGA-25 was the gene with the most stable transcription for comparing different varieties of the fresh pericarp. HDAC9 was the gene with the most stable transcription for postharvest pericarp. STAM was the gene with the most stable transcription for inoculated pericarp. Of the candidate reference genes, GAGA-25 was the most stable reference gene across the complete sample set. This study evaluated reference gene stability for RT-qPCR in litchi pericarp. This work provides a foundation for using qPCR to study gene function and molecular mechanism studies of litchi pericarp browning.

Porous coatings of tin dioxide (SnO2) with a high surface area were obtained using a modified method on glass slides. The coatings were obtained with the “Doctor Blade” method and a closed drying system at room temperature. This drying system provides favorable conditions to decrease significantly cracks on the macroporous coatings. This is an alternative way to synthesize macroporous coatings using polymethylmethacrylate (PMMA) microspheres as a template. A precursor dispersion was made from the mixture of PMMA and tin tetrachloride salt dissolution at 0.5 M. The coatings synthesis parameters were optimized to obtain a uniform porous layer. The precursor dispersion and coatings were studied by thermogravimetric analysis. The coatings material surface area was 87 m2/g determined by BET, and the crystalline structure was characterized by X−ray diffraction. The structure and morphology of the coatings were determined with optical and electron microscope techniques, and the residual contaminations were studied by IR spectroscopy. The macroporous spherical diameter is around 312 ± 35 nm, and they are built by nanocrystalline size particles of 6 ± 1 nm in diameter.

Large-scale transboundary conservation initiatives are necessary to respond to threats against tropical forests, and the jaguar (Panthera onca), a flagship and umbrella species in the Neotropics, is an ideal target species for such initiatives. We estimated jaguar abundance and occupancy of medium- and large-sized mammals and birds across a transboundary landscape in the northwestern Amazon biome using camera-trap data from 168 stations; specifically within three management regimes of indigenous and protected lands in Colombia (the indigenous reserve of Umancia), Ecuador (Cuyabeno Wildlife Reserve), and Peru (Güeppi-Sekime National Park). Based on spatial capture-recapture models, we estimated jaguar density in the study area at 2.20 ± 0.44 individuals per 100 km2, implying an abundance of 322 jaguars (95% CI = 217–477). These estimates suggest that an entire mega-landscape, which also includes other protected areas and indigenous lands, could harbor as many as 2000 jaguars (95% CI = 1586–3498). We found that jaguar abundance and medium-to large-sized terrestrial vertebrate species richness (totaling 24 mammals and 4 birds) were similar under the three management regimes. Overall, our study indicates that a significant healthy population of jaguars can survive in this large-scale conservation corridor that crosses country borders, a place where protected areas and indigenous territories are key. This study is among the first to take a transboundary approach for jaguar conservation in a protected but still threatened part of the Amazon biome, inhabited by several ancient indigenous people. As a large forest block, this conservation landscape serves not only as an effective buffer against deforestation and a stronghold for jaguar populations and medium- and large-sized vertebrates, but it also secures the well-being of local people.

With the continued establishment of hacker-spaces and fab-labs hosted in academic libraries, there is an increase in the availability of resources for designing scientific instrumentation in the undergraduate curriculum. Many available designs, however, may be too complex to fabricate in teaching environments. Presented here is OMIS, the Open Millifluidic Inquiry System, which is a platform for performing small-scale chemical synthesis and analysis. OMIS consists of a 3D printed syringe pump, control hardware based upon the Arduino microcontroller and 3D printed reaction vessels. The OMIS syringe pump utilizes a low-power stepper motor which simplifies the instrument construction and allows for power to be supplied from batteries or the USB port of a computer. The simple design of OMIS allows for the instrument to be fabricated in one day, including the time to 3D print components. The OMIS syringe pump is able to deliver fluids at rates between 60 and 300 μL/min, depending on syringe size, with a reproducibility of 3%. Several applications of OMIS are presented, including a demonstration of laminar flow in a 3D printed millifluidic chip, implementation of a low-volume flow-cell cuvette insert and the synthesis of magnetite nanoparticles. Keywords: 3D printed syringe pump, Arduino microcontroller, Lab on a chip

Although enteropathogenic Escherichia coli (EPEC) are well-recognized diarrheal agents, their ability to translocate and cause extraintestinal alterations is not known. We investigated whether a typical EPEC (tEPEC) and an atypical EPEC (aEPEC) strain translocate and cause microcirculation injury under conditions of intestinal bacterial overgrowth. Bacterial translocation (BT) was induced in female Wistar-EPM rats (200-250 g) by oroduodenal catheterization and inoculation of 10 mL 10(10) colony forming unit (CFU)/mL, with the bacteria being confined between the duodenum and ileum with ligatures. After 2 h, mesenteric lymph nodes (MLN), liver and spleen were cultured for translocated bacteria and BT-related microcirculation changes were monitored in mesenteric and abdominal organs by intravital microscopy and laser Doppler flow, respectively. tEPEC (N = 11) and aEPEC (N = 11) were recovered from MLN (100%), spleen (36.4 and 45.5%), and liver (45.5 and 72.7%) of the animals, respectively. Recovery of the positive control E. coli R-6 (N = 6) was 100% for all compartments. Bacteria were not recovered from extraintestinal sites of controls inoculated with non-pathogenic E. coli strains HB101 (N = 6) and HS (N = 10), or saline. Mesenteric microcirculation injuries were detected with both EPEC strains, but only aEPEC was similar to E. coli R-6 with regard to systemic tissue hypoperfusion. In conclusion, overgrowth of certain aEPEC strains may lead to BT and impairment of the microcirculation in systemic organs.

Although enteropathogenic Escherichia coli (EPEC) are well-recognized diarrheal agents, their ability to translocate and cause extraintestinal alterations is not known. We investigated whether a typical EPEC (tEPEC) and an atypical EPEC (aEPEC) strain translocate and cause microcirculation injury under conditions of intestinal bacterial overgrowth. Bacterial translocation (BT) was induced in female Wistar-EPM rats (200-250 g) by oroduodenal catheterization and inoculation of 10 mL 10(10) colony forming unit (CFU)/mL, with the bacteria being confined between the duodenum and ileum with ligatures. After 2 h, mesenteric lymph nodes (MLN), liver and spleen were cultured for translocated bacteria and BT-related microcirculation changes were monitored in mesenteric and abdominal organs by intravital microscopy and laser Doppler flow, respectively. tEPEC (N = 11) and aEPEC (N = 11) were recovered from MLN (100%), spleen (36.4 and 45.5%), and liver (45.5 and 72.7%) of the animals, respectively. Recovery of the positive control E. coli R-6 (N = 6) was 100% for all compartments. Bacteria were not recovered from extraintestinal sites of controls inoculated with non-pathogenic E. coli strains HB101 (N = 6) and HS (N = 10), or saline. Mesenteric microcirculation injuries were detected with both EPEC strains, but only aEPEC was similar to E. coli R-6 with regard to systemic tissue hypoperfusion. In conclusion, overgrowth of certain aEPEC strains may lead to BT and impairment of the microcirculation in systemic organs.

Objective: to evaluate the efficacy and toxicity of infliximab for the treatment of fistulizing Crohn's disease. Methods: consecutive patients with fistulizing Crohn's disease receiving infliximab were prospectively enrolled. Partial response was defined as a reduction of 50% or more from base-line in the number of draining fistulae. Complete response was defined as the closure of all fistulae. The influence of different variables on the efficacy of infliximab was evaluated. Results: 108 patients were included. The disease was inflammatory plus fistulizing in 18% and only fistulizing in 82%. After the third infusion of infliximab the response was partial in 26% and complete in 57%. Response (%) rates (partial/complete) depending on fistula location were: enterocutaneous (25/68%), perianal (35/60%), rectovaginal (36/64%), and enterovesical (20/40%). None of the studied variables (including concomitant immunosuppressive therapy) correlated with efficacy of infliximab in the multivariate analysis. Incidence of adverse effects (21%) depending on the dose of infliximab was: first dose (5.6%), second (7.4%), and third (11.1%). Conclusions: infliximab is an efficacious treatment for fistulizing Crohn's disease. Partial response was achieved in approximately one third of the patients, and complete response in more than half. No studied variable was predictive of response. Adverse effects were relatively infrequent and mild.Objetivo: evaluar la eficacia e identificar los factores predictivos de respuesta al tratamiento con infliximab en la enfermedad de Crohn fistulizante. Métodos: se realizó un estudio prospectivo en pacientes con enfermedad de Crohn fistulizante que recibían tratamiento con infliximab. La respuesta parcial se definió como una reducción del 50% o más de la línea base en el número de fístulas que drenan. La respuesta completa se definió como el cierre de todas las fístulas. Se evaluó la influencia de diferentes variables sobre la eficacia de infliximab. Resultados: se estudiaron 108 pacientes. La enfermedad era inflamatoria y fistulizante en el 18% y sólo fistulizante en el 82%. Después de la tercera infusión de infliximab la respuesta fue parcial en el 26% y completa en el 57%. Las tasas de respuesta (%) (parcial/completa) dependiendo de la localización de la fístula fueron: enterocutánea (25/68%), perianal (35/60%), rectovaginal (36/64%), y enterovesical (20/40%). Ninguna de las variables estudiadas (edad, sexo, tabaco, tratamiento inmunosupresor, antigüedad, origen y localización de la fístula) presentó correlación con la eficacia de infliximab en el análisis de multivariante. La incidencia de efectos adversos (21%) fue: 5,6,7,4 y 11,1% durante la primera, segunda y tercera dosis respectivamente. Conclusiones: infliximab es un tratamiento eficaz para la enfermedad de Crohn fistulizante. Aproximadamente un tercio de los pacientes alcanzaron respuesta parcial y alrededor de la mitad, respuesta completa. Ninguna variable estudiada fue predictiva de respuesta. Los efectos adversos fueron relativamente infrecuentes y leves.

L’eau d’abreuvement est un besoin incompressible des élevages laitiers. Elle représente un coût non négligeable et sa restriction conduit immédiatement à des baisses de performances et à une altération du bien-être des troupeaux. Le bilan hydrique de l’animal est équilibré grâce à la régulation de l’excrétion rénale d’eau et des volumes d’eau bue en réponse à des consignes de pression osmotique plasmatique et de volume sanguin. De nombreuses équations de prédiction des besoins en eau des vaches laitières ont été publiées. La teneur en matière sèche de la ration ressort comme le premier paramètre prédictif des volumes d’eau bue parce qu’elle détermine la part relative de l’eau provenant de l’aliment et bue dans l’eau totale ingérée. La quantité de matière sèche ingérée, les teneurs en sodium, potassium et azote de la ration ainsi que la température ambiante sont les principaux paramètres prédictifs de l’eau totale ingérée. La comparaison des erreurs de prédiction des équations des besoins en eau des vaches laitières sur un jeu de données commun montre des performances très hétérogènes. Les critères de choix des équations doivent être la nature des paramètres prédictifs disponibles mais aussi les conditions dans lesquelles elles ont été établies. Les équations de prédiction des besoins en eau des vaches laitières ont souvent été établies à partir de mesures individuelles et leur application sur un troupeau disposant d’abreuvoirs à niveau constant peut entrainer un biais de prédiction. Quelques pistes sont évoquées pour quantifier les besoins en eau des génisses.