ABSTRACT
Objective. To analyze the association between daily mortality from different causes and acute exposure to particulate matter less than 10 microns in aerodynamic diameter (PM10), in Bogota, Colombia. Materials and methods. A time-series ecological study was conducted from 1998 to 2006. The association between mortality (due to different causes) and exposure was analyzed using single and distributed lag models and adjusting for potential confounders. Results. For all ages, the cumulative effect of acute mortality from all causes and respiratory causes increased 0.71% (95%CI 0.46-0.96) and 1.43% (95%CI 0.85-2.00), respectively, per 10µg/m³ increment in daily average PM10 with a lag of three days before death. Cumulative effect of mortality from cardiovascular causes was -0.03% (95%CI -0.49-0.44%) with the same lag. Conclusions. The results suggest an association between an increase in PM10 concentrations and acute mortality from all causes and respiratory causes.
Objetivo. Analizar la asociación entre la mortalidad diaria debida a distintas causas y la exposición aguda a partículas menores de 10 micras de diámetro aerodinámico (PM10), en Bogotá, Colombia. Material y métodos. Se realizó un estudio ecológico de series de tiempo (1998-2006). La asociación entre mortalidad y exposición se analizó ajustando modelos de retraso simple y retraso distribuido para diferentes causas de mortalidad. Resultados. En todas las edades, el riesgo acumulado en la mortalidad aguda por todas las causas y causa respiratoria aumentó 0.71% (IC95% 0.46-0.96) y 1.43% (IC95% 0.85-2.00), respectivamente, por incremento de 10µg/m³ en el promedio diario de PM10, tomando un retraso de tres días anteriores al deceso, mientras el riesgo acumulado en la mortalidad por causa cardiovascular fue de -0.03% (IC95% -0.49-0.44), para el mismo retraso. Conclusiones. Los resultados sugieren asociación entre el incremento de las concentraciones de PM10 y la mortalidad aguda por todas las causas y causa respiratoria.
Subject(s)
Animals , Cattle , Bacterial Outer Membrane Proteins/isolation & purification , Mannheimia haemolytica/classification , Autoradiography/methods , Cattle Diseases , Cell Membrane/chemistry , Centrifugation, Density Gradient/methods , Detergents , Electrophoresis, Polyacrylamide Gel , Iodine Radioisotopes , Mannheimia haemolytica/chemistry , Membrane Proteins/isolation & purification , Molecular Weight , Pasteurella Infections/microbiology , Pasteurella Infections/veterinary , Sarcosine/analogs & derivatives , Solubility , SucroseABSTRACT
RQRT-PCR technique was evaluated for its validity as an alternative to Northern blotting for quantification of plant gene expression in diseased tissues of Hevea. Reliable RT-PCR results could be obtained by co-amplification of housekeeping actin gene as the internal control along with the gene of interest. The product of interest was quantified relative to that of the internal control by measuring net intensity of bands. Expression levels of defense-related beta-1,3-glucanase gene was studied in the pathogen infected tissues of rubber. The beta-1,3-glucanase gene was found to be induced in infected leaf tissues and reached a peak at 48 h after inoculation. The beta-1,3-glucanase gene expression during pathogen infection was determined through Northern blot hybridization also, using 18S RNA as the internal control. RQRT-PCR and Northern hybridization showed almost similar results, thereby validating the use of this technique to study the gene expression in rubber.
Subject(s)
Autoradiography/methods , Blotting, Northern , Blotting, Southern , DNA, Complementary/metabolism , Gene Expression Regulation, Plant , Glucan 1,3-beta-Glucosidase/biosynthesis , Hevea/enzymology , Phytophthora/chemistry , Plant Leaves/metabolism , RNA/chemistry , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction/methods , Rubber/metabolism , Time FactorsABSTRACT
The expression of mu-opioid receptors in the developing rat spinal cord (Postnatal days 7, 14, 30) was studied by autoradiography using [3H]DAMGO. When compared to camera lucida drawings, the receptor was noted over the entire gray matter and dorsal root ganglia at postnatal days 7 and 14. At postnatal day 30, the receptor expression decreased over the gray matter except the superficial laminae (laminae I and II). At all age groups studied, a higher expression of the receptor was noted over the superficial laminae. The study shows that micro-opioid receptors appears early in postnatal development and attains mature receptor distribution relatively late in ontogeny, suggesting a possible role in the normal development of nervous system. This is affirmed by an impairment of psychomotor development in babies born to mothers, addicted to opiates.
Subject(s)
Animals , Autoradiography/methods , Models, Anatomic , Rats , Rats, Wistar , Receptors, Opioid, mu/biosynthesis , Spinal Cord/drug effects , Time FactorsABSTRACT
The history of receptor autoradiography, its development and applications, testify to the utility of this histochemical tecnhique for localizing radiolabeled hormones and drugs at cellular and subcelullar sites of action in intact tissues. Loclization of duffusible compounds has been a challenge that was met through the introduction of the "thaw-mount" and "dry-mount" autoradiographic techniques thirty years ago. With this cellular receptor autoradiography, used alone or combined with other histochemical techniques, sites of specific binding and deposition in vivo and in vitro have been characterized. Numerous discoveries, some reviewed in this article, provided information that led to new concepts and opened new areas of research. As an example, in recent years more than fifty target tissues for vitamin D have been specified, challenging the conventional view about the main biological role of vitamin D. The functions of most of these vitamin D target tissues are unrelated to the regulation of systemic calcium homeostasis, but pertain to the (seasonal) regulation of endo- and exocrine secretion, cell proliferation, reproduction, neural, immune and cardiovascular responses, and adaptation to stress. Receptor autoradiography with cellula resolution has become an indispensable tool in drug research and development, since information can be obtained that is difficult or impossible to gain otherwise.
Subject(s)
History, 20th Century , Autoradiography/methods , Binding Sites , Receptors, Calcitriol , Receptors, Steroid , Steroids , Vitamin DABSTRACT
In this study, the sprouting of the vagal nerve terminals were investigated in the ferret stomach after highly selective vagotomy by using the autoradiographic technique. The acute experimental animals which had highly selective vagotomy were injected immediately with tritiated leucine into the vagal dorsal motor nucleus. autoradiographic examination of the body of the stomach failed to show any labelled nerve fibres, while the pylorus showed many labelled nerve fibers. These observations indicate that the highly selective vagotomy has been performed successfully. Abdominal examination, of the chronic experimental animals, three months after highly selective vagotomy. bridges of scar tissue were observed by passing the vagotomy ligatures to supply the stomach. Histological examination of the regrown tissue showed that it was normal nerve fibres. After cutting this regrown tissue and injection of these chronic animals with tritiated leucine into the vagal dorsal motor nucleus, labelled nerve fibres were seen in the body of the stomach. This indicates that terminals reactive sprouting of the vagus nerve has spread from the pylorus to supply the body of the stomach. This phenomenon of the compensatory reactive sprouting of the vagal nerve terminals may explain the recovery of gastric function and may account for the failures of highly selective vagotomy in humans. However, modification of surgery may decrease the high rate of incidence of recurrent peptic ulcer after highly selective vagotomy