Alternative splicing of human prostaglandin G/H synthase mRNA and evidence of differential regulation of the resulting transcripts by transforming growth factor beta 1, interleukin 1 beta, and tumor necrosis factor alpha.

Prostaglandin G/H synthase (PGG/HS) is the rate-limiting enzyme in the conversion of arachidonic acid to prostaglandins and thromboxanes. We screened a human lung fibroblast cDNA library with an ovine PGG/HS cDNA and isolated a 2.3-kilobase clone (HCO-T9). Sequence analysis of this clone showed that (a) it contained the entire translated region of PGG/HS and (b) it displayed an in-frame splicing of the last 111 base pairs encoded by exon 9, which resulted in the elimination of the N-glycosylation site at residue 409. Polymerase chain reaction amplification with specific oligonucleotides of reverse-transcribed mRNA from diverse human tissues and cultured cells yielded 400- and 300-base pair fragments that corresponded, respectively, to the intact and spliced transcripts. The expression of these two transcripts in cultured human lung fibroblasts was differentially regulated by serum, transforming growth factor beta 1, interleukin 1 beta, tumor necrosis factor alpha, and phorbol 12-myristate 13-acetate, as each of these conditions stimulated preferentially the expression of the unspliced transcripts. The elimination of one of the four N-glycosylation sites by the alternative splicing of exon 9 and the differential regulation of this process by relevant cytokines and growth factors may represent a mechanism for the regulation of PGG/HS enzymatic activity under physiological or pathological conditions

A free boundary model for oxygen diffusion in a spherical medium

The goal of this article is to find a correct approximated solution using a polynomial of sixth degree for the free boundary problem corresponding to the diffusion of oxygen in a spherical medium with simultaneous absorption at a constant rate, and to show some mistakes in previously published solutions.Comment: 10 pages, 6 figures and 2 tables. Paper accepted, in press in Journal of Biological Systems (2015

Soil water content and evaporation determined by thermal parameters obtained from ground-based and remote measurements

A procedure is presented for calculating 24-hour totals of evaporation from wet and drying soils. Its application requires a knowledge of the daily solar radiation, the maximum and minimum, air temperatures, moist surface albedo, and maximum and minimum surface temperatures. Tests of the technique on a bare field of Avondale loam at Phoenix, Arizona showed it to be independent of season

Photodynamic therapy plus regulatory T-cell depletion produces immunity against a mouse tumour that expresses a self-antigen

Background: Photodynamic therapy (PDT) can lead to development of antigen-specific immune response and PDT-mediated immunity can be potentiated by T regulatory cell (Treg) depletion. We investigated whether the combination of PDT with cyclophosphamide (CY) could foster immunity against wild-type tumours expressing self-antigen (gp70). Methods: Mice with CT26 tumours were treated with PDT alone or in combination with low-dose CY. T regulatory cell numbers and transforming growth factor-β (TGF-β) levels were measured at several time points after treatment. Mice cured by PDT+CY were rechallenged with CT26 and monitored for long-term survival. Results: Photodynamic therapy+CY led to complete tumour regression and long-term survival in 90% of treated mice while the absolute numbers of Treg decreased after PDT+CY and the TGF-β levels were reduced to a level comparable to naïve mice. Sixty-five percent of the mice treated with PDT+CY that survived over 90 days tumour free rejected the rechallenge with the same tumour when a second dose of CY was administered before rechallenge but not without. Conclusion: Administration of CY before PDT led to depletion of Treg and potentiated PDT-mediated immunity, leading to long-term survival and development of memory immunity that was only uncovered by second Treg depletion

Algoritmo para la sinopsis de videos de vigilancia

Se presenta una técnica para generar una sinopsis de video (o video resumen) que permite realizar un análisis de forma económica y eficiente de las filmaciones provenientes de todas las cámaras de seguridad existentes en un sistema ya instalado, sin necesidad de alteración de dicho sistema. El algoritmo está basado en la estrategia Next-Fit del problema de Bin Packing: los objetos son autos, personas o animales que han sido filmados por las cámaras de vigilancia, y cada bin es un Quadtree que organiza espacio-temporalmente al subconjunto de objetos que no colisionan entre sí. Cuando ya no quedan más objetos por ubicar, se genera el resumen de video a partir de la secuencia de bins . En los experimentos realizados se logró resumir un video de vigilancia, cedido por el Municipio de Tandil (Buenos Aires), de 60 minutos, en el que transcurren 394 objetos, a sólo 8 minutos, con el objetivo de transmitir todas las actividades realizadas por dichos objetos al nuevo video acotado sin que interfieran entre sí y preservando el orden que aparecen en el video original.Sociedad Argentina de Informática e Investigación Operativ

Osteocytic connexin 43 is not required for the increase in bone mass induced by intermittent PTH administration in male mice

Objective: To investigate whether osteocytic connexin 43 (Cx43) is required for the bone response to intermittent PTH administration, and whether the connexin is involved in maintaining the bone matrix. Methods: Human PTH(1-34) was injected to adult male mice expressing (Cx43fl/fl) or not osteocytic Cx43 (Cx43fl/fl;DMP1-8kb-Cre) daily (100 μg/kg/d) for 14 days. Results: Cx43fl/fl;DMP1-8kb-Cre mice have no difference in body weight and BMD from 1 to 4 months of age. Intermittent PTH administration increased BMD and BV/TV and induced a similar increase in type I collagen, alkaline phosphatase, runx2, osteocalcin, and bone sialoprotein expression in mice from both genotypes. On the other hand, osteocytic deletion of Cx43 did not alter mRNA levels of glycosaminoglycans, proteoglycans, collagens and osteoblast-related genes. In addition, expression of collagens assessed by immunohistochemistry was not affected by deleting osteocytic Cx43. However, PTH administration increased type II collagen only in Cx43fl/fl control mice, whereas hormone increased type I collagen expression only in Cx43fl/fl;DMP1-8kb-Cre mice. Furthermore, PTH increased maturity of collagen fibers in control, but not in Cx43-deficient mice. Conclusion: Expression of Cx43 in osteocytes is dispensable for bone anabolism induced by intermittent PTH administration; but it can modulate, at least in part, the effect of PTH on the bone matrix environment

There and back again: molecular phylogenetics of the Brazilian endemic Psyllocarpus (Rubiaceae: Spermacoceae) supports a circumscription of the genus based on its original concept

The Spermacoce clade (tribe Spermacoceae) is one of the most taxonomically complex groups in Rubiaceae due to the unclear delimitation of Borreria and Spermacoce, in which several smaller genera are phylogenetically intermingled. One of these genera is the Brazilian endemic Psyllocarpus, whose circumscription was broadened, thereby including two sections. Psyllocarpus sect. Psyllocarpus, being based on the original genus delineation, includes nine species, distributed in the Cerrado and campo rupestre of eastern Brazil, whereas P. sect. Amazonica comprises three species, occurring in the Amazonian campinas. Furthermore, P. intermedius was not classified in any of these sections when it was later described. In order to test the monophyly of Psyllocarpus and assess its relationships to other genera, we conducted phylogenetic analyses, sampling across the whole Spermacoce clade, including nearly all Psyllocarpus species. A combined nuclear ribosomal (ETS and ITS) and plastid (rps16 and trnLtrnF) dataset was generated, representing 124 species (ca 25% of the species in the clade) in 15 genera (ca 65%). Various methodologies were applied to investigate the degree of incongruence among markers and address the lack of resolution and low support values for some branches. Our results revealed that Psyllocarpus is not monophyletic. Psyllocarpus campinorum (from P . sect. Amazonica) and P intermedius are situated as distinct lineages in the Spermacoce clade, yet do not belong to Psyllocarpus. Members of section Psyllocarpus form a strongly supported clade sister to Staelia and was recovered with high to maximum support across different datasets and inference methods. Therefore, Psyllocarpus has to be circumscribed based on its original concept, excluding P. sect. Amazonica and P. intermedius. This establishes the genus as a monophyletic and easily diagnosable taxon, characterized by terete leaves, homostylous flowers, a bilobate calyx, included stamens and style, and compressed, septifragally dehiscent capsules with a persistent septum