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1.
Indoor Air ; 19(1): 45-57, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19191927

RESUMO

UNLABELLED: The purpose of this study was to measure and evaluate the impact of the emissions of selected products of exotic wood on health. Ten products were screened for chemical compounds, and five of the most used products which emitted more than 800 microg/kg were selected for further quantitative analyses by climate chamber measurement (iroko, ramin, sheesham, merbau, and rubber tree). Samples of exotic wood (rubber tree and belalu) were further analyzed for emission of chemical compounds by migration into artificial saliva and for content of pesticides and allergenic natural rubber latex (NR latex) (rubber tree). The toxicological effects of all substances identified were evaluated and the lowest concentrations of interest (LCI) assessed. An R-value was calculated for each wood product (R-value below 1 is considered to be unproblematic as regards health). Emission from the evaluated exotic wood only took place to a very limited extent. None of the selected products, under the chosen rating system, is likely to cause adverse health effects. Products with surface treatment might pose a problem if used as kitchen utensils, as children's toys, or when they are in close contact with the skin for a long time. PRACTICAL IMPLICATIONS: The authors investigated the chemical emissions from selected products from exotic wood by climate chamber measurement. Quantitative chemical analyses of emissions from the five most used exotic products in Denmark were performed, and all chemical compounds found were evaluated toxicologically. Emission from the evaluated exotic wood was very limited. None of the products is likely, under our exposure conditions, to cause health problems in relation to indoor air.


Assuntos
Resíduos de Praguicidas/análise , Compostos Orgânicos Voláteis/toxicidade , Madeira/química , Poluição do Ar em Ambientes Fechados/análise , Humanos , Saliva Artificial/química , Compostos Orgânicos Voláteis/análise
2.
J Interferon Cytokine Res ; 18(9): 793-8, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9781819

RESUMO

Much evidence implicates interleukin-1beta (IL-1beta) in sleep regulation. Two previous studies indicated that levels of IL-1beta in mRNA were affected by sleep. In the current study, levels of IL-1beta mRNA and IL-1 receptor assessory protein (IL-1RAP) mRNA were determined 1 h after the beginning of light and dark periods and after sleep deprivation, using the reverse transcriptase-polymerase chain reaction (RT-PCR) and mutated internal standards. Daytime samples contained relatively more IL-1beta mRNA than nighttime samples, and levels of IL-1beta mRNA were higher after sleep deprivation. These changes occurred in the hypothalamus, hippocampus, cerebral cortex, and mesencephalon/pons. In contrast, the IL-1 RAP mRNA level did not seem to be affected by sleep.


Assuntos
Encéfalo/metabolismo , Interleucina-1/genética , RNA Mensageiro/biossíntese , Privação do Sono/fisiologia , Sono/fisiologia , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia
3.
Sleep ; 22(6): 707-15, 1999 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10505816

RESUMO

The liver Kupffer cells constitute the largest population of fixed macrophages in the body and reside at a strategic position in liver sinusoids to interact with mediators from the gut. Previously, we showed that cafeteria feeding increases sleep by a subdiaphragmatic mechanism and increases interleukin-1beta (IL-1beta) mRNA expression in rat liver and brain. Thus, the aim of the present experiment was to test the hypothesis that macrophages, in particular liver Kupffer cells, contribute to the excess sleep observed in cafeteria diet fed rats. Sleep-wake activity and brain temperature (T(br)) were examined in rats injected with gadolinium chloride (GdCl3) alone and in rats fed a cafeteria diet with or without prior pretreatment with GdCl3. The intravenous administration of GdCl3 alone, using a dose that blocks phagocytosis and eliminates large Kupffer cells (7.5 mg/kg), increased sleep in the dark period of the light-dark cycle and decreased sleep in the light period. Sleep-wake activity returned to baseline levels 24 h after the injection. In control rats, cafeteria feeding increased non-rapid eye movement sleep (NREMS) and T(br), and decreased rapid eye movement sleep (REMS) and electroencephalographic slow-wave activity (SWA) during NREMS. GdCl3 pretreatment prevented the increase in NREMS, but did not significantly affect REMS, T(br), or SWA during NREMS compared with the control rats. These results suggest that liver Kupffer cells contribute to the excess NREMS that accompanies increased feeding possibly via their capacity to produce IL-1beta.


Assuntos
Meios de Contraste/farmacologia , Dieta , Gadolínio/farmacologia , Sono REM/efeitos dos fármacos , Animais , Temperatura Corporal/efeitos dos fármacos , Eletroencefalografia , Eletromiografia , Ingestão de Energia/efeitos dos fármacos , Injeções Intravenosas , Interleucina-1/metabolismo , Macrófagos/efeitos dos fármacos , Masculino , RNA Mensageiro/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Vigília/efeitos dos fármacos
4.
J Appl Physiol (1985) ; 95(5): 1873-82, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12871965

RESUMO

Peripheral administration of a variety of inflammatory stimuli, such as endotoxin or cytokines, induces an orchestrated set of brain-mediated events referred to as the sickness response. The mechanism for how immune products signal the brain is not clear, but accumulating evidence supports the existence of neural as well as blood-borne pathways. Although endotoxin or cytokine administration results in sickness responses, few data exist regarding the role of circulating endotoxin or cytokines in the induction of sickness during a real bacterial infection. Thus the present studies examined whether subcutaneously administered Escherichia coli can activate sickness responses and whether circulating endotoxin and/or proinflammatory cytokines are a prerequisite for these responses. Male Sprague-Dawley rats were injected subcutaneously with one of three doses (2.5 x 10(7), 2.5 x 10(8), 2.5 x 10(9) colony-forming units) of replicating E. coli, a ubiquitous bacterial strain, or vehicle. Core body temperature (Tc) and activity were measured for 3 days after the injection. A second set of groups of animals were killed 3, 6, 12, 18, 24, and 48 h after the injection, and blood samples and brains were collected. Injections dose dependently and consistently increased Tc and decreased activity, with increases in Tc beginning 4 h after the injection. In addition, E. coli significantly increased serum interleukin (IL)-1beta, IL-6, and tumor necrosis factor-alpha and brain IL-1beta levels beginning at the 6-h time point. Corticosterone and endotoxin were first elevated in the circulation at 3 and 18 h after the injection, respectively. Because fever onset preceded brain cytokine induction, we also examined cytokine levels in the serum, brain, and inflammation site 2 and 4 h after injection. Cytokines were elevated at the inflammation site but were not detectable in the serum or brain at 2 and 4 h. We conclude that subcutaneous injection of replicating E. coli induces a consistent and naturalistic infection that includes features of the sickness response as well as increases in circulating, brain, and inflammation site tissue cytokines. In addition, injection of replicating E. coli produces a robust fever and corticosterone response at a time when there are no detectable increases in circulating cytokines or endotoxin. These results suggest that elevated levels of circulating cytokines and endotoxin are not necessary for the activation of the sickness or corticosterone response. Therefore, fever, activity reduction, and corticosterone elevation induced by E. coli infection may have been evoked by a neural, rather than a humoral, pathway from the periphery to the brain.


Assuntos
Corticosterona/sangue , Infecções por Escherichia coli/imunologia , Interleucina-1/imunologia , Neuroimunomodulação/fisiologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Encéfalo/imunologia , Encéfalo/microbiologia , Infecções por Escherichia coli/sangue , Febre/imunologia , Febre/microbiologia , Interleucina-1/metabolismo , Lipopolissacarídeos/sangue , Masculino , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
5.
Brain Res ; 859(2): 193-201, 2000 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-10719064

RESUMO

Activation of peripheral immune cells leads to increases of interleukin-1beta (IL-1beta) mRNA, immunoreactivity, and protein levels in brain and pituitary. Furthermore, IL-1beta in brain plays a role in mediating many of the behavioral, physiological, and endocrine adjustments induced by immune activation. A similarity between the consequences of immune activation and exposure to stressors has often been noted, but the potential relationship between stress and brain IL-1beta has received very little attention. A prior report indicated that exposure to inescapable tailshocks (IS) raised levels of brain IL-1beta protein 2 h after IS, but only in adrenalectomized (and basal corticosterone replaced) subjects. The studies reported here explore this issue in more detail. A more careful examination revealed that IL-1beta protein levels in hypothalamus were elevated by IS in intact subjects, although adrenalectomy, ADX (with basal corticosterone replacement) exaggerated this effect. IL-1beta protein increases were already present immediately after the stress session, both in the hypothalamus and in other brain regions in adrenalectomized subjects, and no longer present 24 h later. Furthermore, IS elevated levels of IL-1beta protein in the pituitary, and did so in both intact and adrenalectomized subjects. IS also produced increased blood levels of IL-1beta, but only in adrenalectomized subjects. Finally, the administration of corticosterone in an amount that led to blood levels in adrenalectomized subjects that match those produced by IS, inhibited the IS-induced rise in IL-1beta in hypothalamus and pituitary, but not in other brain regions or blood.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Corticosterona/metabolismo , Corticosterona/farmacologia , Interleucina-1/sangue , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Estresse Fisiológico/fisiopatologia , Fatores de Tempo , Adrenalectomia/efeitos adversos , Animais , Encéfalo/citologia , Masculino , Hipófise/citologia , Ratos , Ratos Sprague-Dawley
6.
J Pain ; 2(6): 326-33, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14622812

RESUMO

Intrathecal administration of the human immunodeficiency virus-1 envelope glycoprotein, gp120, activates astrocytes and microglia to release products that induce thermal hyperalgesia and mechanical allodynia. Both pain states are disrupted by intrathecal CNI-1493, a p38 mitogen-activated protein (MAP) kinase inhibitor. Whether CNI-1493, or any other p38 MAP kinase inhibitor, can cross the blood-brain barrier to affect spinal cord function is unknown. Given that several such drugs are in clinical trials, it is of interest to determine whether they may be potentially useful in treating centrally mediated pain. The aim of the present studies was to determine whether systemic CNI-1493 could block intrathecal gp120-induced thermal hyperalgesia and/or mechanical allodynia. Because p38 MAP kinase inhibition would be expected to prevent proinflammatory cytokine release and/or signal transduction, we sought to determine from the same animals the likely mechanism by which CNI-1493 blocks gp120-induced pain states. These studies show that systemic CNI-1493 blocks intrathecal gp120-induced thermal hyperalgesia and mechanical allodynia. Because CNI-1493 did not block proinflammatory cytokine release, this may suggest disruption at the level of signal transduction. These studies provide the first evidence that systemic p38 MAP kinase inhibitors can prevent centrally mediated exaggerated pain states. Thus, CNI-1493 may provide a novel therapeutic approach for the treatment of pain.

7.
Neurosci Lett ; 195(3): 163-6, 1995 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-8584200

RESUMO

This study examines the effect of acetylcholine (Ach) on parasympathetic vagal neurons in the dorsal motor nucleus of the vagus (DMNX). Patch-clamp techniques were utilized to examine voltage and ligand-gated currents in visualized DMNX neurons in an in vitro slice. Ach (100 microM) activated an inward current, -196.4 +/- 56.9 pA at -80 mV (n = 15) that was accompanied by a decrease in membrane resistance of 48.6 +/- 9.2% in a population of DMNX neurons. The reversal potential for this ligand-gated current was -11.3 +/- 11.5 mV. The specific agonist nicotine (200 microM) elicited similar responses. Nicotine decreased membrane resistance by 60.9 +/- 4.3% and activated an inward current (-215.7 +/- 45.7 pA at -80 mV) that reversed at -12.7 +/- 20.4 mV (n = 16). Bethanecol (100 microM), a specific muscarinic agonist, had no effect. Neither Ach or nicotine had any effect on the voltage-gated sodium and outward potassium currents present in these neurons.


Assuntos
Acetilcolina/fisiologia , Neurônios Motores/fisiologia , Receptores Nicotínicos/fisiologia , Nervo Vago/fisiologia , Animais , Betanecol/farmacologia , Potenciais da Membrana/fisiologia , Neurônios Motores/ultraestrutura , Agonistas Muscarínicos/farmacologia , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Técnicas de Patch-Clamp , Canais de Potássio/fisiologia , Ratos , Ratos Sprague-Dawley , Nervo Vago/citologia
8.
Life Sci ; 65(5): 449-81, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10462074

RESUMO

Interleukin-1beta (IL-1beta) is a key mediator and modulator of a wide array of physiological responses important for survival. It is created by a variety of cell types, including immune cells, glia, and neurons. It is a very potent biological molecule, acting both at the periphery as well as within the central nervous system. The production and release of IL-1beta is tightly regulated by far more complex processes than previously thought. An appreciation of this complexity is necessary for proper interpretation of apparent contradictions in the literature where different aspects of IL-1beta expression are measured. Given that many researchers are not molecular biologists by training, yet need an appreciation of the controls that regulate the function of key proteins such as IL-1beta, this review is aimed at both: (a) clarifying the multiple levels at which IL-1beta production is modulated and (b) using IL-1beta regulation to explain the dynamics of gene regulation to non-molecular biologists. Three major topics will be discussed. First, regulation of IL-1beta production will be examined at every level from extracellular signals that trigger gene activation through release of active protein into the extracellular fluid. Second, regulation of IL-1beta bioavailability and bioactivity will be discussed. This section examines the fact that even after IL-1beta is released, it may or may not be able to exert a biological action due to multiple modulatory factors. Last is the introduction of the idea that IL-1beta regulation is, at times, beyond the direct control of host; that is, when IL-1beta production becomes dysregulated by pathogens.


Assuntos
Interleucina-1/fisiologia , Receptores de Interleucina-1/fisiologia , Transdução de Sinais , Animais , Regulação da Expressão Gênica/imunologia , Humanos , Inflamação , Ativação Transcricional
9.
Physiol Behav ; 64(3): 361-5, 1998 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9748105

RESUMO

Cytokines, such as interleukin-1beta (IL-1beta), are involved in physiological sleep regulation and in the sleep responses to sleep deprivation. Sleep deprivation increases systemic cytokine levels and recent evidence suggests that cytokine-to-brain communication occurs via the vagus nerve. Furthermore, the vagus nerve plays a role in sleep responses elicited by feeding and vagal activity affects electroencephalographic (EEG) activity. Thus, this study examined sleep-wake activity and brain temperature (Tbr) responses to sleep deprivation in subdiaphragmatically vagotomized and sham-operated rats. In control rats, 6 h of total sleep deprivation significantly increased nonrapid eye movement sleep (NREMS), rapid eye movement sleep (REMS), and electroencephalographic slow-wave activity during nonrapid eye movement sleep. Brain temperature was significantly increased during the 6 h of sleep deprivation and decreased following sleep deprivation. Vagotomy had no significant effects on any of these variables. These results indicate that the subdiaphragmatic vagus nerve is not critical in the sleep and thermoregulatory responses after 6 h of sleep deprivation. Together with other data, the current results suggest that central pools of interleukin-1 are important in moderate sleep deprivation-induced sleep responses and that vagotomy does not disrupt the ability to increase sleep using a well-known sleep-inducing stimulus likely mediated by brain cytokines.


Assuntos
Privação do Sono/fisiologia , Sono/fisiologia , Vagotomia , Animais , Diafragma/inervação , Ingestão de Alimentos/fisiologia , Masculino , Polissonografia , Piloro/fisiologia , Ratos , Ratos Sprague-Dawley , Sono REM/fisiologia
10.
Phys Med Biol ; 42(9): 1843-7, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9308088

RESUMO

Port wine stains (PWSs) treated with a flashlamp-pumped pulsed dye laser show a variability in clinical response that is incompletely understood. To identify any vascular structure that might adversely affect treatment response, we obtained a three-dimensional reconstruction of the vascular anatomy of a non-responsive, light-purple superficial PWS on the forearm. The reconstructed PWS consisted of multiple clusters of small diameter (10-50 microns) blood vessels. We propose that this and similar structures, which have not been identified in the literature, have limited the efficacy of laser therapy. Further study is required to clarify the role of vessel clusters for laser treatment of PWSs, and the corresponding dosimetry necessary to clear non-responsive lesions. We expect that three-dimensional reconstruction of PWS vascular anatomy will provide the basis for (i) accurate PWS classification, (ii) guidance for selection of more effective laser dosimetry, and (iii) a standard against which to assess non-invasive diagnostic imaging techniques.


Assuntos
Vasos Sanguíneos/patologia , Processamento de Imagem Assistida por Computador/métodos , Mancha Vinho do Porto/patologia , Adulto , Volume Sanguíneo , Feminino , Humanos , Terapia a Laser , Mancha Vinho do Porto/fisiopatologia , Mancha Vinho do Porto/cirurgia
11.
Eur J Cardiothorac Surg ; 3(6): 512-4, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2635937

RESUMO

The prophylactic treatment of the application of fibrin glue to the pulmonary surface during thoracoscopy in idiopathic spontaneous pneumothorax resulted in rapid and total pulmonary expansion in 33 of 35 patients. The 2 failures were due to apical cysts larger than 2 cm. The successfully treated patients were hospitalized for a median of 4 days (range 2-12). No complications were observed. All regained full working capacity within 1 month of discharge. Post-treatment X-ray examination of the chest was uniformly normal. During an observation time ranging from 7-24 months (median 12 months), 3 recurrences (9%) were seen at 7, 12, and 16 months, respectively. The treatment seems (1) to reduce the need for thoracotomy (2) to be associated with a high success rate, short and long-term, (3) to minimize the duration of hospital stay and (4) not to disturb the normal pleuro-pulmonary anatomy.


Assuntos
Adesivo Tecidual de Fibrina/uso terapêutico , Pneumotórax/terapia , Toracoscopia , Administração por Inalação , Adulto , Tubos Torácicos , Protocolos Clínicos/normas , Adesivo Tecidual de Fibrina/administração & dosagem , Seguimentos , Humanos , Tempo de Internação , Pessoa de Meia-Idade , Pneumotórax/diagnóstico por imagem , Pneumotórax/etiologia , Radiografia , Recidiva
12.
Auton Neurosci ; 85(1-3): 72-7, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11189029

RESUMO

Peripheral interleukin-1beta has been implicated in the initiation of fever responses, yet the pathways by which it influences brain function are still unclear. Sectioning the abdominal vagus has been reported to inhibit fever after intraperitoneal administration of interleukin-1beta, suggesting that vagal afferents participate in signaling the brain to mount a fever response to interleukin-1beta. However, the inhibitory effect of subdiaphragmatic vagotomy could be due to alterations in pharmacokinetics such that the intraperitoneally injected cytokine does not reach the general circulation in sufficient quantities to activate the brain via blood-borne signaling. We measured both fever and plasma levels of interleukin-1beta in vagotomized and sham-operated rats after intraperitoneal administration of 1 microg/kg human recombinant interleukin-1beta to determine whether vagotomy reduces fever and levels of circulating interleukin-1beta after intraperitoneal injection. Plasma levels of human recombinant and endogenous rat interleukin-1beta were measured in separate enzyme-linked immunosorbent assays. While intraperitoneal administration of human recombinant interleukin-1beta elevated plasma levels of this cytokine similarly in vagotomized and sham-operated animals, only sham-operated rats responded with fever. Plasma levels of endogenous rat interleukin-1beta were unchanged by any treatment. These results demonstrate that the blockade of intraperitoneal interleukin-1beta-induced fever after subdiaphragmatic vagotomy cannot be accounted for by alterations of interleukin-1beta levels in the general circulation.


Assuntos
Febre/imunologia , Interleucina-1/sangue , Interleucina-1/imunologia , Vagotomia/métodos , Nervo Vago/imunologia , Animais , Diafragma , Febre/sangue , Manobra Psicológica , Humanos , Injeções Intraperitoneais , Interleucina-1/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Termogênese/imunologia , Nervo Vago/cirurgia
13.
Auton Neurosci ; 85(1-3): 119-26, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11189018

RESUMO

The production of interleukin-1beta (IL-1beta) in brain is thought to be a critical step in the induction of central manifestations of the acute phase response, and the vagus nerve has been implicated in immune-to-brain communication. Thus, this study examined the effects of intraperitoneal (i.p.) injections of lipopolysaccharide (LPS) on brain IL-1beta protein levels in control and subdiaphragmatically vagotomized rats. In the first experiment, vagotomized and sham-operated male Sprague-Dawley rats were injected i.p. with one of three doses (10, 50, 100 microg/kg) of LPS or vehicle (sterile, pyrogen-free saline) and sacrificed 2 h after the injection. In the second experiment, vagotomized and sham-operated rats were injected i.p. with 100 microg/kg LPS or vehicle and sacrificed 1 h after the injection. The i.p. injection of LPS dose-dependently increased IL-1beta protein levels in the hypothalamus, hippocampus, dorsal vagal complex, cerebellum, posterior cortex, and pituitary 2 h after the injection. Brain and pituitary IL-1beta levels were also significantly increased 1 h after the injection of 100 microg/kg LPS. There were no significant differences in brain IL-1beta levels between sham-operated and vagotomized rats at either the 2 h or 1 h time points. The current data are consistent with previous studies showing increases in brain IL-1beta after peripheral injections of LPS, and support the notion that brain IL-1beta is a mediator in the illness-induction pathway. Furthermore, these data indicate that, at the doses and times tested, subdiaphragmatic vagal afferents are not crucial for LPS-induced brain IL-1beta protein.


Assuntos
Química Encefálica/imunologia , Interleucina-1/metabolismo , Vagotomia , Nervo Vago/imunologia , Animais , Cerebelo/citologia , Cerebelo/imunologia , Cerebelo/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/imunologia , Córtex Cerebral/metabolismo , Colecistocinina/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Hipocampo/citologia , Hipocampo/imunologia , Hipocampo/metabolismo , Hipotálamo/citologia , Hipotálamo/imunologia , Hipotálamo/metabolismo , Injeções Intraperitoneais , Interleucina-1/imunologia , Lipopolissacarídeos/sangue , Lipopolissacarídeos/farmacocinética , Masculino , Neuroimunomodulação/fisiologia , Hipófise/imunologia , Hipófise/metabolismo , Ratos , Ratos Sprague-Dawley , Nervo Vago/citologia , Nervo Vago/cirurgia
14.
Auton Neurosci ; 85(1-3): 49-59, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11189026

RESUMO

The immune system operates as a diffuse sensory system, detecting the presence of specific chemical constituents associated with dangerous micro-organisms, and then signalling the brain. In this way, immunosensation constitutes a chemosensory system. Several submodalities of this sensory system function as pathways conveying immune-related information, and can be classified as either primarily brain barrier associated or neural. The vagus nerve provides the major neural pathway identified to date. The initial chemosensory transduction events occur in immune cells, which respond to specific chemical components expressed by dangerous micro-organisms. These immune chemosensory cells release mediators, such as cytokines, to activate neural elements, including primary afferent neurons of the vagal sensory ganglia. Primary afferent activation initiates local reflexes (e.g. cardiovascular and gastrointestinal) that support host defense. In addition, at least three parallel pathways of ascending immune-related information activate specific components of the illness response. In this way, immunosensory systems represent highly organized and coherent pathways for activating host defense against infection.


Assuntos
Encéfalo/citologia , Encéfalo/imunologia , Neuroimunomodulação/fisiologia , Neurônios Aferentes/imunologia , Nervo Vago/citologia , Nervo Vago/imunologia , Animais , Células Quimiorreceptoras/imunologia
15.
Auton Neurosci ; 85(1-3): 83-7, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11189031

RESUMO

Several recent findings, including the inability of subdiaphragmatic vagotomy to block lipopolysaccharide (LPS)-induced interleukin-1beta (IL-1beta) protein in brain, have made it necessary to reexamine the role of the subdiaphragmatic vagal afferents in immune-to-brain communication. In this study, we examined the effects of intraperitoneal (i.p.) injections of LPS on core body temperature in control and subdiaphragmatically vagotomized rats. Vagotomized and sham-operated male Sprague-Dawley rats were injected i.p. with vehicle (pyrogen-free saline) on the control day and LPS (1, 10 or 50 microg/kg) on the experimental day, and core body temperature was monitored by telemetry for 6 h after the injection. At this time, rats were sacrificed, and serum, liver, and pituitary samples were collected. The i.p. injection of LPS increased core body temperature in both sham-operated and vagotomized rats compared to the saline injection. In addition, LPS significantly increased IL-1beta levels in serum, liver, and pituitary compared to saline-injected controls. There were no significant differences in the magnitude of the fever or in the levels of IL-1beta in serum, liver, or pituitary between sham-operated and vagotomized rats. Thus, the current data indicate that, at the doses tested, subdiaphragmatic vagal afferents are not crucial for i.p. LPS-induced fever. Because several effects of vagotomy have been shown to be dependent on dose, we are currently investigating whether vagal afferents are involved in lower-dose i.p. LPS-induced fever.


Assuntos
Febre/fisiopatologia , Neuroimunomodulação/fisiologia , Vagotomia/métodos , Nervo Vago/imunologia , Animais , Encéfalo/citologia , Encéfalo/imunologia , Colecistocinina/farmacologia , Diafragma , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Febre/induzido quimicamente , Febre/imunologia , Injeções Intraperitoneais , Interleucina-1/análise , Interleucina-1/sangue , Lipopolissacarídeos/farmacologia , Fígado/química , Fígado/imunologia , Masculino , Hipófise/química , Hipófise/imunologia , Ratos , Ratos Sprague-Dawley , Nervo Vago/citologia , Nervo Vago/cirurgia
16.
Scand J Work Environ Health ; 13(6): 473-85, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3324321

RESUMO

This work presents information on the composition of waterborne construction paints used in Denmark, data from determinations of chemicals evaporating from paints applied with a brush or roller, and the toxicology of these chemicals. Seven product types were selected to illustrate the composition of the paints. Measurements at two workplaces were used as models for the work environment during painting. Evaporating chemicals were collected on Tenax TA and analyzed with capillary column gas chromatography after thermal desorption. In smudging work, waterborne paints may result in skin irritation and/or sensitization when safety precautions are not taken. Irritation of the mucous membranes may be expected if airing is not sufficient. This irritation may lead to headache mediated by trigeminal nerve stimulation. No other health hazards (eg, brain damage) are expected. The available information indicates that waterborne paints are a clear improvement over traditional paints which use white spirit as the main solvent.


Assuntos
Pintura/intoxicação , Borracha/intoxicação , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/intoxicação , Humanos , Doenças Profissionais/induzido quimicamente , Pintura/análise , Borracha/análise , Água
17.
Dis Aquat Organ ; 47(3): 183-91, 2001 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-11804417

RESUMO

The absorption, distribution and elimination of 14C-labelled flumequine were studied using whole body autoradiography and liquid scintillation counting. Flumequine was administered to eel Anguilla anguilla, turbot Scophthalmus maximus and halibut Hippoglossus hippoglossus intravenously and orally as a single dose of 5 mg kg(-1), corresponding to 0.1 mCi kg(-1). The turbot and halibut studies were performed in salt water (salinity of 32%) at temperatures of 16 +/- 1 degrees C (turbot) and 9.5 +/- 0.5 degrees C (halibut). The eel study was conducted in fresh water at 23 +/- 1 degrees C. In the intravenously administered groups flumequine was rapidly distributed to all major tissues and organs. After oral administration flumequine also appeared to have rapid and extensive absorption and distribution in all 3 species. After the distribution phase, the level of flumequine was higher in most organs and tissues than in the blood, except in muscle and brain. The most noticeable difference between the species was the slow elimination of flumequine from eel compared to turbot and halibut. In orally administered eels, substantial amounts of flumequine remained in all major organs/tissues for 7 d. At 28 d significant levels of flumequine were present in liver, kidney and skin (with traces in muscle), and at the last sampling point (56 d) in eye, bone, bile and posterior intestine. In orally administered turbot significant levels of flumequine were observed over 96 h in bile, urine, bone, skin, intestine and eye, and traces were detected over 28 d in bone and eye in addition to a significant level in bile. In orally administered halibut, significant levels of flumequine were observed in bile, skin, intestine and eye over 96 h. Traces were present in skin and eye over 7 d. The maximal flumequine concentrations in blood were calculated to be 2.5 mg equivalents l(-1) (eel at 12 h), 0.8 mg l(-1) (turbot at 6 h) and 0.6 mg l(-1) (halibut at 6 h) after oral administration.


Assuntos
Anguilla/metabolismo , Anti-Infecciosos/farmacocinética , Linguados/metabolismo , Linguado/metabolismo , Fluoroquinolonas , Quinolizinas/farmacocinética , Absorção , Administração Oral , Animais , Anti-Infecciosos/administração & dosagem , Autorradiografia/veterinária , Isótopos de Carbono , Injeções Intravenosas/veterinária , Quinolizinas/administração & dosagem , Contagem de Cintilação/veterinária , Especificidade da Espécie , Distribuição Tecidual
18.
Dis Aquat Organ ; 50(3): 161-9, 2002 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-12219972

RESUMO

This is the first description of a persistent subclinical nodavirus infection in the Atlantic halibut Hippoglossus hippoglossus. Juvenile fish (1 to 5 g) were sampled at 4, 5 and 8 mo of age at a fish farm in Norway during and after weaning. None showed clinical signs of viral encephalopathy and retinopathy (VER) or other disease. Pathological changes and/or nodavirus were detected by light microscopy, immunohistochemistry, reverse transcriptase polymerase chain reaction (RT-PCR) and transmission electron microscopy in all fish examined. High numbers of virus particles were found in macrophage-like cells in the central nervous system, including brain and retina (CNS). The virus particles displayed the icosahedral shape and size (approximately 25 nm) characteristic of nodaviruses. The virus-infected cells formed focal cell aggregates and were seen in all regions of the brain and all nuclear cell layers of the retina. The cytoplasm of the infected cells was filled with membrane-enclosed inclusions packed with virus particles. Some virus particles lay along membranes and formed membrane-bound necklace-like arrangements. The virus-infected cells of the retina also contained pigment granula located generally inside virus inclusions and sometimes forming a coating around the virus particles. All frontal parts with the eyes and brain and 50% of the mid-parts, which included the abdominal organs, were found positive for nodavirus with RT-PCR. Pathological changes in these persistently nodavirus-infected fish differ from earlier descriptions in Atlantic halibut during outbreaks of VER. Vertical transmission from infected spawners is believed to be a major route for nodavirus infection. Detection of nodavirus in subclinical infected fish and a better understanding of its pathogenesis are important in order to prevent the spread of nodavirus in the fish-farming industry.


Assuntos
Doenças dos Peixes/patologia , Linguado , Nodaviridae/isolamento & purificação , Infecções por Vírus de RNA/veterinária , Animais , Encéfalo/patologia , Encéfalo/ultraestrutura , Encéfalo/virologia , Doenças dos Peixes/transmissão , Doenças dos Peixes/virologia , Pesqueiros , Imuno-Histoquímica/veterinária , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/veterinária , Microscopia Eletrônica/veterinária , Nodaviridae/genética , Noruega , Infecções por Vírus de RNA/patologia , Infecções por Vírus de RNA/transmissão , RNA Viral/análise , Retina/patologia , Retina/ultraestrutura , Retina/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária
19.
Acta Cytol ; 35(1): 47-50, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1994634

RESUMO

The cytologic histories of 376 women presenting with invasive carcinoma of the cervix were analyzed. In total, 202 (53.7%) of these women had had 355 smears taken during the three years preceding presentation. All 320 smears with an original cytologic diagnosis of less than cancer were reviewed. The original cytologic diagnosis was low in 95 (30.6%) of 310 adequate smears. Originally, 96 (30.9%) of the adequate smears were evaluated as negative; at review, only 55 (17.5%) of the adequate smears were evaluated as negative. Comparing the review diagnoses to the 355 total smears, the rates of negative smears were 13.5% (42 of 310) for squamous-cell carcinoma, 30.0% (12 of 40) for adenocarcinoma and 20.0% (1 of 5) for adenosquamous carcinoma (P less than .05). The cellular composition of the smear was significantly related to the cytologic detection of abnormalities: endocervical cylindrical and/or metaplastic cells were seen in only 45.5% of smears diagnosed as negative, but in 84.4% and 97.8% of smears diagnosed as atypia and cervical intraepithelial neoplasia, respectively P less than .00001). Smears without endocervical cells should be considered inadequate and should be repeated.


Assuntos
Neoplasias do Colo do Útero/diagnóstico , Esfregaço Vaginal , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Reações Falso-Negativas , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/patologia
20.
Arch Environ Health ; 56(5): 419-32, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11777023

RESUMO

In this study, the authors describe a method for evaluation of material emissions. The study was based on chemical analysis of emissions from 23 materials representing solid wood and wood-based materials commonly used in furniture, interior furnishings, and building products in Denmark in the 1990s. The authors used the emission chamber testing method to examine the selected materials with a qualitative screening and quantitative determination of volatile organic compounds. The authors evaluated the toxicological effects of all substances identified with chamber testing. Lowest concentration of interest and standard room concentrations were assessed, and the authors calculated an S-value for each wood and wood-based material. The authors identified 144 different chemical substances with the screening analyses, and a total of 84 individual substances were quantified with chamber measurements. The irritative effects dominated at low exposure levels; therefore, the lowest concentration of interest and the S-value were based predominantly on these effects. The S-values were very low for solid ash, oak, and beech. For solid spruce and pine, the determining substances for size of the S-value were delta3-carene, alpha-pinene, and limonene. For the surface-treated wood materials, the S-value reflected the emitted substances from the surface treatment.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Compostos Orgânicos/análise , Madeira , Materiais de Construção , Humanos , Decoração de Interiores e Mobiliário , Nível de Efeito Adverso não Observado , Odorantes , Volatilização
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