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Summary 1 The pressor action of the α1A-adrenoceptor (α1A-AR) agonist A61603 (N-[5-(4,5-dihydro-1H-imidazol-2-yl)-2-hydroxy-5,6,7,8-tetrahydronaphthalen-1-yl] methanesulfonamide) and the α1-ARs agonist phenylephrine and their blockade by selective α1-ARs antagonists in the isolated mesenteric vascular bed of wild-type (WT) mice and α1D-AR knockout (KO α1D-AR) mice were evaluated. 2 The apparent potency of A61603 to increase the perfusion pressure in the mesenteric vascular bed of WT and KO α1D-AR mice is 86 and 138 times the affinity of phenylephrine, respectively. 3 A61603 also enhanced the perfusion pressure by ≈1.7 fold in the mesenteric vascular bed of WT mice compared with KO α1D-AR mice. 4 Because of its high affinity, low concentrations of the α1A-AR selective antagonist RS100329 (5-methyl-3-[3-[4-[2-(2,2,2,-trifluoroethoxy) phenyl]-1-piperazinyl] propyl]-2,4-(1H)-pyrimidinedione) shifted the agonist concentration–response curves to the right in the mesenteric vascular bed of WT and KO α1D-AR mice. 5 The α1D-AR selective antagonist BMY7378 (8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4.5] decane-7,9-dione) did not modify the A61603 or the phenylephrine-induced pressor effect. 6 The α1B/D-ARs alkylating antagonist chloroethylclonidine (CEC) shifted the agonist concentration–response curves to the right and decreased the maximum phenylephrine-induced vascular contraction in KO α1D-AR mice when compared to WT mice; however, CEC only slightly modified the contraction induced by A61603. 7 The results indicate that the isolated mesenteric vascular bed of WT and KO α1D-AR mice expresses α1A-AR, that the pressor action of α1A-AR is up-regulated for α1D-AR in WT mice and suggest an important role of α1B-AR in the vascular pressure evoked by phenylephrine in KO α1D-AR mice.

In this note, we report the simple development of a homemade versatile device that allows micrometric vertical micro-positioning for computer-controlled dip-coating thin film deposition and micro-contact printing capabilities. Using mostly recycled parts, the resulting low-cost setup offers great precision, ease of use, and portability while complying with common soft lithography technique's specifications. It results in an excellent benchtop alternative to more expensive commercial solutions or more complex custom soft lithography devices, especially for organic electronics and quantum optics applications.

Abstract Background Dialysate protein loss is involved in the etiology of hypoalbuminemia and malnutrition on continuous ambulatory peritoneal dialysis (CAPD). Patients with high peritoneal membrane permeability had the lowest serum albumin (Alb) and highest dialysate protein concentrations and achieved higher small solute dialysis/plasma equilibration in a shorter time than patients with low peritoneal transport. The aim of this prospective crossover study was to evaluate whether protein loss might be decreased in patients with high peritoneal permeability on short dwell-time (DT) peritoneal dialysis. Methods Five high and nine high-average peritoneal transport patients were subjected to the following sequential dialysis schemes (four exchanges/day, glucose 1.5%): scheme A, three daytime exchanges (4–6 h DT) and one nightly (8–12 h DT) for 2–3 days, scheme B, 3-h DT each and dry peritoneum at night during 5 days, a wash-out period similar to scheme A, and scheme C, 2-h DT each and dry peritoneum the remainder of day and night during 5 days. Dialysate Alb, IgG, IgA, and IgM losses and adequacy of dialysis were evaluated at the end of each scheme. Results Dialysate IgM was not detected. All protein losses were reduced with the short DT dialysis schemes; however, dialysis CCl and KT/V urea were also decreased. In patients with high peritoneal transport type, the 3-h DT dialysis scheme achieved a reduction in Alb loss without significant reduction of adequacy of dialysis. Conclusions Peritoneal Alb, IgG, and IgA losses are significantly reduced in patients with high peritoneal permeability on short dwell-time dialysis and extended dry periods. However, a reduction of dialysis contribution to small solute clearances was also observed, Three-hour dwell-time dialysis may be particularly useful in patients with high peritoneal transport type, as it tends to reduce peritoneal protein loss without notably reducing adequacy of dialysis.

Novel gamma-Fe2O3@APTES@rGO composites are successfully synthesized by using graphene oxide and silanized maghemite nanoparticles. Graphene oxide and maghemite were obtained by Hummers and Massart methods, respectively. The silanization process was done to functionalize maghemite surface with a controllable quantity of amino groups. Then, by adding aqueous graphene oxide suspension, the bonding between graphene oxide and silanized maghemite nanoparticles was done in refluxing conditions. Afterwards, chemical reduced graphene oxide reaction was realized by addition of hydrazine solution. The characterization of gamma-Fe2O3@APTES@rGO composites was studied by X-ray Diffraction, Fourier Transformed Infrared Spectroscopy, thermogravimetric analysis and scanning electron microscopy. Fil: Cosio Castañeda, Carlos. Universidad Nacional Autónoma de México; México. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería; Argentina Fil: Martinez Garcia, Ricardo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Tecnologia En Polimeros y Nanotecnologia; Argentina Fil: Socolovsky, Leandro Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería; Argentina

Aim For epiphytic plants trees are habitat units, and tree size determines epiphyte species richness. While growing, trees generate vertical microhabitats that are exploited by epiphytes. One would expect to find four different types of relationship between tree size and epiphyte species richness: positive linear (young trees), neutral (old trees), negative (old decaying trees) and positive asymptotic (trees of mixed size class in a mature forest). We tested these relationships in plots of colonizing sweetgum trees in pastureland, isolated remnant trees in pastureland (old oaks) and sweetgum and oaks in a pristine forest. Location The study was carried out in a landscape shaped by the fragmentation of lower montane cloud forest in San Andres Tlalnelhuayocan (19°30′56′′ N and 96°59′50′′ W; 1500–1600 m a.s.l.) in central Veracruz, Mexico. Methods We measured the d.b.h. of all oaks and sweetgum trees (d.b.h. ≥ 5 cm) present in pastureland and in three 100 m2 plots of a lower montane cloud forest. All trees were climbed and species richness of the epiphytes recorded. Results As expected, colonizer trees in pastureland showed a linear positive relationship. Although we found evidence that remnant oaks in pastureland had a neutral relationship between tree size and epiphyte species richness, the low power of the test did not allow us to make conclusions about the kind of relationship. Mixed size-class pristine forest trees showed a positive linear relationship between tree size and epiphyte species richness instead of a positive asymptotic one. Main conclusions Our results suggest that in the study area epiphyte communities are unsaturated, as the number of species increases with tree size and does not reach a ceiling. This evidence supports the idea that the species–area relationship is not asymptotic. However, the epiphyte community on remnant pastureland oaks may be saturated as epiphyte species richness did not increase with tree size, but a larger sample size is needed to confirm the neutral pattern. Neutral, asymptotic and negative patterns in the relationship between tree size and epiphyte species richness depend on the saturation of the trees by epiphytes. Other studies have suggested tree saturation, but further research is necessary in order to confirm or rule out these patterns.

Abstract In the present work we demonstrate a novel single-soliton ultra-low pulse repetition frequency passively mode-locked erbium-doped fiber laser. We mitigate the residual linear birefringence of fiber by fiber twist to achieve a strict control of polarization. For mode-locking the nonlinear polarization rotation (NPR) was used. Special technique was applied to reduce the overdriving of NPR that allows the generation of single soliton in ultra-long cavity. The strict control of polarization yields a stable relation between the polarization state of the pulses propagating in the cavity and the regimes of generation. A 192.12-kHz train of soliton pulses was obtained with pulse duration of 4.7 ps at 1560.1 nm, the average power was 29 μW and the estimated peak power was 30.8 W with an energy of 150.9 pJ.

The Dirac equation, with minimal coupling, is analysed in order to show that the Zitterbewegung (rapid oscillatory motion) also arises when a static and uniform magnetic field is taken into account. The corresponding equations of motion are solved in the Heisenberg picture with the weak-field approximation.

Se presenta un estudio preliminar sobre las especies de Coleoptera Melolonthidae establecidas en los terrenos dedicados a la agricultura de riego en el rancho La Joya, Atlixco, Puebla, situado a 1,700 m de altitud. Durante 21 eventos de recolecta diurnos y nocturnos realizados entre 1996 y 1999, se obtuvo una muestra formada por 1,563 individuos adultos y 292 larvas, que representan a 21 especies de los géneros Phyllophaga, Macrodactylus, Anomala, Cyclocephala, Strategus y Ligyrus. La mayor diversidad específica correspondió a Phyllophaga, representado por 8 especies, entre las que predomina ampliamente Ph. ravida (Blanch.), la cuál junto con Ph. ilhuicaminai Morón, causan daño a las raíces de los cultivos de estatis Limonium sinuatum (L.) La baja diversidad de Melolonthidae de esta localidad corresponde con las condiciones propias de las zonas dedicadas a la agricultura en los valles y altiplanos centrales de México.

ABSTRACT Plantago ovata F. are small tan-colored seeds with ≈30% weight husk. Plantago's husk high content of soluble fiber makes it a good lubricant of the intestinal track with demonstrated effects in lowering plasma cholesterol levels in humans and experimental animals. Plantago seeds grown in Northern Mexico were analyzed for proximate composition, combustion heat, soluble and insoluble dietary fiber, fatty acids, amino acids, and protein fractionation. In vitro digestibility and digestibility of dry matter, apparent and true digestibility, and net protein ratio (in vivo) were also analyzed. Plantago seeds had 17.4% protein, 6.7% fat, 24.6% total dietary fiber, 19.6% insoluble fiber, 5.0% soluble fiber, and a combustion heat of 4.75 kcal/g. Osborne fractionation (based on solubility) yielded albumin 35.8%, globulin 23.9%, and prolamin 11.7%. The oil from plantago seeds had a high percentage of linoleic acid (40.6%) and oleic acid (39.1%) and a minor proportion of linolenic acid (6.9%). In vitro protei...

Abstract: This study aims to evaluate the clinicopathological features, TNM status, AJCC staging and behavior of squamous cell carcinoma of the tongue (SCCT) in patients older than 45 years. The files of the Department of Pathology of the Hospital General de México were reviewed and all cases of SCCT in patients older than 45 years were selected. Clinicopathological features, treatment, follow-up, microscopic diagnosis, and IJCC and TNM staging were retrieved. Complete data from 60 cases were evaluated. They were more common in males (mean age = 63.9 years). Unexpectedly a high rate of tumors (38.3%) were in the base of the tongue (BT). Moderately and poorly differentiated SCCT were the most common. 16.7% presented lymph node invasion, 15% were recurrent tumors and BT carcinomas recurred more frequently. A high rate (81.7%) were stage II and 48.3% were low-risk patients. SCCTs in the studied population displayed different clinico-pathological and behavioral features compared with worldwide data. Our results suggest that BT tumors should be treated more aggressively than those in the mobile tongue. BT located tumors were more frequent than previously published. Additional frequency studies will define outcomes in age cohorts with a consensus cut-off for young and elderly populations. More population-based studies should be performed in Latin American regions to acquire accurate data on SCC incidence in elder subpopulations and to identify precisely the etiological factors in these patients.