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OBJECTIVE: The aim of this work was to assess baseline serum levels of established biomarkers related to inflammation and oxidative stress in samples from alkaptonuric subjects enrolled in SONIA1 (n = 40) and SONIA2 (n = 138) clinical trials (DevelopAKUre project). METHODS: Baseline serum levels of Serum Amyloid A (SAA), IL-6, IL-1ß, TNFα, CRP, cathepsin D (CATD), IL-1ra, and MMP-3 were determined through commercial ELISA assays. Chitotriosidase activity was assessed through a fluorimetric method. Advanced Oxidation Protein Products (AOPP) were determined by spectrophotometry. Thiols, S-thiolated proteins and Protein Thiolation Index (PTI) were determined by spectrophotometry and HPLC. Patients' quality of life was assessed through validated questionnaires. RESULTS: We found that SAA serum levels were significantly increased compared to reference threshold in 57.5% and 86% of SONIA1 and SONIA2 samples, respectively. Similarly, chitotriosidase activity was above the reference threshold in half of SONIA2 samples, whereas CRP levels were increased only in a minority of samples. CATD, IL-1ß, IL-6, TNFα, MMP-3, AOPP, thiols, S-thiolated protein and PTI showed no statistically significant differences from control population. We provided evidence that alkaptonuric patients presenting with significantly higher SAA, chitotriosidase activity and PTI reported more often a decreased quality of life. This suggests that worsening of symptoms in alkaptonuria (AKU) is paralleled by increased inflammation and oxidative stress, which might play a role in disease progression. CONCLUSIONS: Monitoring of SAA may be suggested in AKU to evaluate inflammation. Though further evidence is needed, SAA, chitotriosidase activity and PTI might be proposed as disease activity markers in AKU.
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Alcaptonuria/sangre , Inflamación/sangre , Estrés Oxidativo , Adulto , Productos Avanzados de Oxidación de Proteínas/sangre , Alcaptonuria/metabolismo , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Catepsina D/sangre , Femenino , Hexosaminidasas/sangre , Humanos , Inflamación/metabolismo , Interleucina-1beta/sangre , Interleucina-6/sangre , Masculino , Metaloproteinasa 3 de la Matriz/sangre , Persona de Mediana Edad , Proteína Amiloide A Sérica/análisis , Compuestos de Sulfhidrilo/sangre , Factor de Necrosis Tumoral alfa/sangre , Adulto JovenRESUMEN
Size-dependent characteristics of novel engineered nanomaterials might result in unforeseen biological responses and toxicity. To address this issue, we used cDNA microarray analysis (13443 genes) coupled with bioinformatics and functional gene annotation studies to investigate the transcriptional profiles of Balb/3T3 cells exposed to a low dose (1 μM) of cobalt nanoparticles (CoNP), microparticles (CoMP) and ions (Co2+). CoNP, CoMP and Co2+ affected 124, 91 and 80 genes, respectively. Hierarchical clustering revealed two main gene clusters, one up-regulated, mainly after Co2+, the other down-regulated, mainly after CoNP and CoMP. The significant Gene Ontology (GO) terms included oxygen binding and transport and hemoglobin binding for Co2+, while the GOs of CoMP and CoNP were related to nucleus and intracellular components. Pathway analysis highlighted: i) mitochondrial dysfunction for Co2+, ii) signaling, activation of innate immunity, and apoptosis for CoNP, and iii) cell metabolism, G1/S cell cycle checkpoint regulation and signaling for CoMP. Unlike ions, particles affected toxicologically-relevant pathways implicated in carcinogenesis and inflammation.
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Cobalto/toxicidad , Nanopartículas del Metal/toxicidad , Transcriptoma/efectos de los fármacos , Animales , Células 3T3 BALB , Ratones , Mitocondrias/efectos de los fármacos , Análisis de Secuencia por Matrices de OligonucleótidosRESUMEN
There is a considerable public and scientific debate concerning welfare of fish in aquaculture. In this review, we will consider fish welfare as an integration of physiological, behavioral, and cognitive/emotional responses, all of which are essentially adaptative responses to stressful situations. An overview of fish welfare in this context suggests that understanding will rely on knowledge of all components of allostatic responses to stress and environmental perturbations. The development of genomic technologies provides new approaches to this task, exemplified by how genome-wide analysis of genetic structures and corresponding expression patterns can lead to the discovery of new aspects of adaptative responses. We will illustrate how the genomic approach may give rise to new biomarkers for fish welfare and also increase our understanding of the interaction between physiological, behavioral, and emotional responses. In a first part, we present data on expression of candidate genes selected a priori. This is a common avenue to develop molecular biomarkers capable of diagnosing a stress condition at its earliest onset, in order to allow quick corrective intervention in an aquaculture setting. However, most of these studies address isolated physiological functions and stress responses that may not be truly indicative of animal welfare, and there is only rudimentary understanding of genes related to possible cognitive and emotional responses in fish. We also present an overview on transcriptomic analysis related to the effect of aquaculture stressors, environmental changes (temperature, salinity, hypoxia), or concerning specific behavioral patterns. These studies illustrate the potential of genomic approaches to characterize the complexity of the molecular mechanisms which underlies not only physiological but also behavioral responses in relation to fish welfare. Thirdly, we address proteomic studies on biological responses to stressors such as salinity change and hypoxia. We will also consider proteomic studies developed in mammals in relation to anxiety and depressive status which may lead to new potential candidates in fish. Finally, in the conclusion, we will suggest new developments to facilitate an integrated view of fish welfare. This includes use of laser microdissection in the transcriptomic/proteomic studies, development of meta-analysis methods for extracting information from genomic data sets, and implementation of technological advances for high-throughput proteomic studies. Development of these new approaches should be as productive for our understanding of the biological processes underlying fish welfare as it has been for the progress of pathophysiological research.
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Bienestar del Animal , Peces/fisiología , Genómica , Alostasis , Animales , Conducta Animal/fisiología , Explotaciones Pesqueras , Peces/genética , Regulación de la Expresión Génica , Proteómica , Estrés FisiológicoRESUMEN
Closed university buildings proved to be one of the main hot spots for virus transmission during pandemics. As shown during the COVID-19 pandemic, physical distancing is one of the most effective measures to limit such transmission. As universities prepare to manage in-class activities, students' adherence to physical distancing requirements is a priority topic. Unfortunately, while physical distancing in classrooms can be easily managed, the movement of students inside common spaces can pose high risk of close proximity. This paper provides an experimental analysis of unidirectional student movement inside a case-study university building to investigate how physical distancing requirements impact student movement and grouping behaviour. Results show general adherence with the minimum required physical distancing guidance, but spaces such as corridors pose higher risk of exposure than doorways. Doorway width, in combination with group behaviour, affect the students' capacity to keep the recommended physical distance. Furthermore, questionnaire results show that students report higher perceived vulnerability while moving along corridors. Evidence-based results can support decision-makers in understanding individuals' exposure to COVID-19 in universities and researchers in developing behavioural models in preparation of future outbreaks and pandemics.
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The interaction between NPs and immune system has been demonstrated, however, the data available are limited. Among all traits, i.s. hydrophilicity, lipophilicity, catalytic activity, composition, electronic structure, capacity to bind or coat surface species and solubility, the dimension, and consequently the surface area, seems to be the main factor that contribute to the interactions of NPs with biological tissues and immune system in particular. Certain NPs accumulate to regional lymph nodes, where they can be taken up and processed by dendritic cells, interact with self-proteins and, hence, modify their antigenicity and elicit altered immune responses and even autoimmunity. Other NPs may induce allergic sensitization, i.e. allergic contact dermatitis to Pd. In vitro studies demonstrated that NPs can modulate cytokine production toward Th1 (Pl, Pd, Ni, Co) or Th2 (Ti, mw and sw Carbon) production patterns. Some NPs have been linked to allergic sensitization, however, It is unlikely that NPs can act as a hapten inducing a specific IgE production, likely they can act as adjuvant and induce a specific pattern of cytokines, antibody and cells that favor allergic sensitization to environmental allergens. Furthermore, NPs demonstrated pro-inflammatory effects in the lung in experimental animal with increased expression on IL-1beta, MIP-1alpha, MCP-1, MIP-2, keratinocyte chemoattractant, TARC, GM-CSF, MIP-1alpha and activation of the stress-activated MAPKs p38 and JNKs. All considered, the available data suggest that through the elicitation of an oxidative stress mechanism, engineered NPs may contribute to pro-inflammatory disease processes in the lung, particularly allergy.
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Sistema Inmunológico/efectos de los fármacos , Nanopartículas/toxicidad , Animales , Citocinas/biosíntesis , Humanos , Hipersensibilidad/etiología , Sistema Inmunológico/inmunología , Neumonía/etiologíaRESUMEN
The uric acid degradation pathway is progressively lost during vertebrate evolution. In mammals, the end product of this catabolic pathway is allantoin and, therefore, no allantoicase should be present in mouse tissues. Surprisingly, we have found an expressed sequence tag (EST) from mouse testis with high similarity to allantoicase. To characterize this transcript, we have completely sequenced the corresponding EST clone insert and found a 1495 bp long cDNA coding for a 414 amino acid long protein. Identities of mouse versus microorganism allantoicases range from 25 to 30%. Identity reaches 54% when compared to Xenopus allantoicase. Among the tested tissues, only testis possesses the allantoicase transcript. Although no deleterious mutations were found in the coding region, no allantoicase activity could be detected in mouse testis.
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ADN Complementario/biosíntesis , Ureohidrolasas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN Complementario/química , Evolución Molecular , Etiquetas de Secuencia Expresada , Masculino , Ratones , Datos de Secuencia Molecular , Alineación de Secuencia , Testículo/metabolismoRESUMEN
This study reports on the selective adsorption of whole plasma proteins on hydrothermally (HT) grown TiO2-anatase coatings and its dependence on the three main surface properties: surface charge, wettability and roughness. The influence of the photo-activation of TiO2 by UV irradiation was also evaluated. Even though the protein adhesion onto Ti-based substrates was only moderate, better adsorption of any protein (at pH = 7.4) occurred for the most negatively charged and hydrophobic substrate (Ti non-treated) and for the most nanorough and hydrophilic surface (HT Ti3), indicating that the mutual action of the surface characteristics is responsible for the attraction and adhesion of the proteins. The HT coatings showed a higher adsorption of certain proteins (albumin 'passivation' layer, apolipoproteins, vitamin D-binding protein, ceruloplasmin, α-2-HS-glycoprotein) and higher ratios of albumin to fibrinogen and albumin to immunoglobulin γ-chains. The UV pre-irradiation affected the surface properties and strongly reduced the adsorption of the proteins. These results provide in-depth knowledge about the characterization of nanocrystalline TiO2 coatings for body implants and provide a basis for future studies on the hemocompatibility and biocompatibility of such surfaces.
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Proteínas Sanguíneas/química , Materiales Biocompatibles Revestidos/química , Nanopartículas/química , Titanio/química , Adsorción , Dureza , Humanos , Ensayo de Materiales , Nanopartículas/ultraestructura , Unión Proteica , Electricidad Estática , HumectabilidadRESUMEN
It has been shown that certain alkanols such as heptanol and octanol reversibly uncouple crayfish axons. We have studied the effects of heptanol on the electrical coupling in Xenopus embryo cells and on the gap junction particle distribution of stomach and pancreas epithelia. Cell-to-cell electrical communication in Xenopus embryos reversibly decreases 10-15 min after the beginning of heptanol superfusion to reach values of coupling ratio lower than 0.05. Particle density of rat stomach and pancreas gap junction reversibly increases after exposure to heptanol-Tyrode's solutions. In stomach, gap junction particles from isles with hexagonal patterns after 10 to 15 min; in pancreas crystallization occurs after 20 to 30 min. Optical diffractions are used to average particle spacings in treated and control junctions of pancreas.
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Alcoholes/farmacología , Comunicación Celular , Uniones Intercelulares/fisiología , Páncreas/fisiología , Estómago/fisiología , Animales , Conductividad Eléctrica , Embrión no Mamífero , Femenino , Técnica de Fractura por Congelación , Heptanol , Uniones Intercelulares/efectos de los fármacos , Uniones Intercelulares/ultraestructura , Masculino , Potenciales de la Membrana/efectos de los fármacos , Microelectrodos , Microscopía Electrónica , Ratas , XenopusRESUMEN
BACKGROUND AND PURPOSE: Hospital mortality rates of 50% to 90% have been reported for stroke patients treated with mechanical ventilation. These data have raised serious questions about the cost-effectiveness of this intervention. We sought to determine how often stroke patients are mechanically ventilated, identify predictors of 30-day survival among ventilated patients, and evaluate the cost-effectiveness of this intervention. METHODS: We identified mechanically ventilated patients in a population-based multiethnic cohort of 510 incidence stroke patients who were hospitalized between July 1993 and June 1996. Factors affecting 30-day survival were identified in a multiple logistic regression analysis. We calculated the cost per patient discharged alive, life-year saved, and quality-adjusted life-year saved using a zero-cost, zero-life assumption. RESULTS: Ten percent of patients (n=52) were mechanically ventilated. Thirty-day mortality was 65% overall and did not differ significantly by stroke subtype. Glasgow Coma Scale score on the day of intubation (P:<0.01) and subsequent neurological deterioration (P:=0.02) were identified as predictors of 30-day mortality. The cost (1996 US dollars) of hospitalization per patient discharged alive was $89 400; the cost per year of life saved was $37 600; and the cost per quality-adjusted life-year saved was $174 200. Functional status of most survivors was poor; at 6 months, half were severely disabled and completely dependent. In a worst-case scenario of quality of life preferences, mechanical ventilation resulted in a net deficit of meaningful survival. CONCLUSIONS: Two thirds of mechanically ventilated stroke patients die during their hospitalization, and most survivors are severely disabled. Survival is particularly unlikely if patients are deeply comatose or clinically deteriorate after intubation. In our multiethnic urban population, mechanical ventilation for stroke was relatively cost-effective for extending life but not for preserving quality of life.
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Respiración Artificial/economía , Respiración Artificial/estadística & datos numéricos , Accidente Cerebrovascular/terapia , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Análisis Costo-Beneficio , Femenino , Escala de Coma de Glasgow , Costos de la Atención en Salud/estadística & datos numéricos , Humanos , Cuidados para Prolongación de la Vida/economía , Modelos Logísticos , Masculino , Persona de Mediana Edad , Ciudad de Nueva York , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Accidente Cerebrovascular/economía , Accidente Cerebrovascular/mortalidad , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: Because there is considerable variation in practice patterns and outcomes for carotid endarterectomy (CE), there is a need to study the processes of care that are associated with adverse outcomes. The purpose of this study was to examine the impact of processes of care and surgical specialty on adverse outcomes for CE. METHODS: A retrospective cohort study based on a voluntary CE registry containing 3644 patients undergoing CE between April 1, 1997, and March 31, 1999, in New York hospitals was used in the study. A multivariable statistical model was used to identify significant independent patient risk factors and to examine the association of processes of care and surgical specialty with outcomes after adjustment for differences in patient risk factors. RESULTS: The overall adverse outcome (in-hospital death or stroke) rate was 1.84%. After adjustment for differences in 7 patient risk factors that were significantly related to adverse outcomes, the use of >/=1 specific processes of care (eversion endarterectomy, protamine, or shunts) was found to be associated with lower odds of an adverse outcome relative to patients undergoing CE without the processes (OR=0.42, P=0.006). Similarly, patients undergoing surgery performed by vascular surgeons had lower odds of experiencing an adverse outcome (OR=0.36, P=0.009). Processes of care and surgical specialty were highly correlated with one another. CONCLUSIONS: Processes of care and surgical specialty are significant interrelated determinants of adverse outcome for CE.
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Endarterectomía Carotidea/efectos adversos , Endarterectomía Carotidea/estadística & datos numéricos , Evaluación de Procesos y Resultados en Atención de Salud/estadística & datos numéricos , Especialidades Quirúrgicas/normas , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Endarterectomía Carotidea/métodos , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Modelos Estadísticos , Análisis Multivariante , New York/epidemiología , Oportunidad Relativa , Complicaciones Posoperatorias/epidemiología , Prevalencia , Sistema de Registros/estadística & datos numéricos , Estudios Retrospectivos , Factores de RiesgoRESUMEN
BACKGROUND AND PURPOSE: Thick cisternal clot on CT is a well-recognized risk factor for delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH). Whether intraventricular hemorrhage (IVH) or intracerebral hemorrhage (ICH) predisposes to DCI is unclear. The Fisher CT grading scale identifies thick SAH but does not separately account for IVH or ICH. METHODS: We studied 276 consecutively admitted patients with an available admission CT scan performed within 72 hours of onset. Demographic, clinical, laboratory, and neuroimaging data were recorded, and the amount and location of SAH, IVH, and ICH on admission CT scans were quantified. The relationship between these variables and DCI was analyzed separately and in combination with multiple logistic regression. RESULTS: DCI developed in 20% of patients (54 of 276). Among SAH variables, thick clot completely filling any cistern or fissure was the best predictor of DCI (P=0.008), and among IVH variables, blood in both lateral ventricles was most predictive (P=0.001). These variables had independent predictive value for DCI in a multivariate analysis of CT findings, and both were included in a final multivariate model when evaluated in conjunction with other clinical risk factors: IVH (OR 4.1, 95% CI 1.7 to 9.8), SAH (OR 2.3, 95% CI 1.5 to 9.5), mean arterial pressure >112 mm Hg (OR 4.9, 95% CI 2.1 to 11.4), and transcranial Doppler mean velocity >140 cm/s within 5 days of hemorrhage (OR 3.8, 95% CI 1.5 to 9.5). Similar results were obtained in a repeat analysis with infarction due to vasospasm as the dependent variable. CONCLUSIONS: SAH completely filling any cistern or fissure and IVH in the lateral ventricles are both risk factors for DCI, and their risk is additive. We propose a new SAH rating scale that accounts for the independent predictive value of subarachnoid and ventricular blood for DCI.
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Isquemia Encefálica/etiología , Ventrículos Cerebrales , Cisterna Magna , Índice de Severidad de la Enfermedad , Hemorragia Subaracnoidea/complicaciones , Trombosis/complicaciones , Isquemia Encefálica/diagnóstico , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/diagnóstico , Infarto Cerebral/diagnóstico , Infarto Cerebral/etiología , Cisterna Magna/diagnóstico por imagen , Demografía , Femenino , Estudios de Seguimiento , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Variaciones Dependientes del Observador , Oportunidad Relativa , Valor Predictivo de las Pruebas , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Hemorragia Subaracnoidea/clasificación , Hemorragia Subaracnoidea/diagnóstico , Trombosis/diagnóstico , Tomografía Computarizada por Rayos XRESUMEN
Uric-acid-degrading enzymes (uricase, allantoinase, allantoicase, ureidoglycolate lyase and urease) were lost during vertebrate evolution and the causes for this loss are still unclear. We have recently cloned the first vertebrate allantoicase cDNA from the amphibian Xenopus laevis. Surprisingly, we have found some mammalian expressed sequence tags (ESTs) that show high similarity with Xenopus allantoicase cDNA. From a human fetal spleen cDNA library and adult kidney EST clone, we have obtained a 1790 nucleotide long cDNA. The 3' end of this sequence reveals a substantial high identity with the corresponding portion of Xenopus allantoicase cDNA. In contrast, at the 5' end the human sequence diverges from that of Xenopus; since no continuous open reading frame can be found in this region, the hypothetical human protein appears truncated at its N-terminus. We proposed that such a transcript could be due to an incorrect splicing mechanism that introduces an intron portion at the 5' end of human cDNA. Allantoicase cDNA is expressed in adult testis, prostate, kidney and fetal spleen. By comparison with available genomic sequences deposited in database, we have determined that the human allantoicase gene consists of five exons and spans 8kb. We have also mapped the gene in chromosome 2.
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Ureohidrolasas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Northern Blotting , Mapeo Cromosómico , Cromosomas Humanos Par 2/genética , Clonación Molecular , ADN Complementario/química , ADN Complementario/genética , Exones , Femenino , Regulación Enzimológica de la Expresión Génica , Genes/genética , Humanos , Intrones , Masculino , Datos de Secuencia Molecular , ARN/genética , ARN/metabolismo , Mapeo de Híbrido por Radiación , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Distribución Tisular , Ureohidrolasas/metabolismoRESUMEN
Five cases of presumed nicotine withdrawal delirium among brain-injured patients treated in a neurologic intensive care unit are presented. Each patient had a history of heavy tobacco use and experienced dramatic and sustained clinical improvement within hours of transdermal nicotine replacement. These preliminary observations suggest that nicotine withdrawal may be an under-recognized cause of delirium in patients with acute brain injury.
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Delirio/etiología , Enfermedades del Sistema Nervioso/fisiopatología , Nicotina/efectos adversos , Síndrome de Abstinencia a Sustancias/complicaciones , Administración Cutánea , Adulto , Anciano , Delirio/fisiopatología , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Nicotina/administración & dosificación , Síndrome de Abstinencia a Sustancias/fisiopatologíaRESUMEN
BACKGROUND: Cognitive dysfunction is the most common form of neurologic impairment after subarachnoid hemorrhage (SAH). OBJECTIVE: To evaluate the impact of global and domain-specific cognitive impairment on functional recovery and quality of life (QOL) after SAH. METHODS: One hundred thirteen patients (mean age 49 years; 68% women) were evaluated 3 months after SAH. Three simple tests of global mental status and neuropsychological tests to assess seven specific cognitive domains were administered. Four aspects of outcome (global handicap, disability, emotional status, and QOL) were compared between cognitively impaired and unimpaired patients with analysis-of-covariance models controlling for age, race/ethnicity, and education. Multiple linear regression was used to evaluate the relative contribution of global and domain-specific cognitive status for predicting concurrent modified Rankin Scale (mRS) and Sickness Impact Profile (SIP) scores. RESULTS: Impairment of global mental status on the Telephone Interview of Cognitive Status (TICS) was associated with poor performance in all seven cognitive domains (all p < 0.0005) and was the only cognitive measure associated with poor recovery in all four aspects of outcome (all p < or = 0.005). Cognitive impairment in four specific domains was also associated with functional disability or reduced QOL. After accounting for global cognitive impairment with the TICS, however, neuropsychological testing did not contribute additional predictive value for concurrent mRS or SIP total scores. CONCLUSIONS: Cognitive impairment impacts broadly on functional status, emotional health, and QOL after SAH. The TICS may be a useful alternative to more detailed neuropsychological testing for detecting clinically relevant global cognitive impairment after SAH.
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Trastornos del Conocimiento/psicología , Hemorragia Subaracnoidea/psicología , Adulto , Anciano , Anciano de 80 o más Años , Ansiedad/etiología , Ansiedad/psicología , Trastornos del Conocimiento/etiología , Cuidados Críticos , Evaluación de la Discapacidad , Emociones , Femenino , Estudios de Seguimiento , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Calidad de Vida/psicología , Hemorragia Subaracnoidea/complicaciones , Resultado del TratamientoRESUMEN
Previous studies have shown that cell uncoupling is paralleled by an increase in tightness and crystallinity of gap junction particle arrays. Gap junction crystallinity is believed to be part of the uncoupling mechanism because it can be produced in gap junctions isolated from lens fibers on direct exposure to uncoupling agents such as divalent cations or hydrogen ions. Some doubts, however, have been raised on the capacity of lens fiber junctions to crystallize and uncouple in situ. The present study shows that the gap junctions of rat lens fibers indeed crystallize after a treatment that increases drastically the membrane permeability to ions. The treatment consists of a brief immersion of the lenses in liquid nitrogen, followed by incubation for several hours in Tyrode's solution at 37 degrees C. Immediately after liquid nitrogen treatment, the lenses start gaining sodium and calcium while losing potassium, and eventually become opaque. Addition of 10 mM EDTA to calcium and magnesium-free Tyrode's solutions inhibits particle crystallization and lens cataract, whereas low concentrations of EDTA (1 mM) are not effective. These findings, together with preliminary data on the capacity of lens fibers to heal over, indicate that the gap junctions of lens fibers are capable of crystallizing and uncoupling in situ.
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Calcio/fisiología , Catarata/fisiopatología , Cristalino/fisiología , Animales , Cristalización , Ácido Edético/farmacología , Congelación , Cristalino/efectos de los fármacos , Cristalino/ultraestructura , Microscopía Electrónica , Potasio/fisiología , Ratas , Sodio/fisiología , Desacopladores/farmacologíaRESUMEN
beta-Endorphin was injected into the third cerebral ventricle (ICV) of conscious, unrestrained cats. Hyperthermic response to 50 microgram of this peptide were reduced by 20-100 microgram naloxone given ICV 1 hr later. A dose of 40 microgram beta-endorphin increased body temperature at ambient temperature of 4, 22 and 34 degrees C, with the response being greater the warmer the environment. These results indicate that beta-endorphin acts on a central naloxone-sensitive receptor which is probably the v2 receptor that is activated by low doses of D-Ala2-Met-enkephalinamide to evoke a similar pattern of change in body temperature over a comparable range of ambient temperatures.
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Temperatura Corporal/efectos de los fármacos , Endorfinas/farmacología , Naloxona/farmacología , Animales , Gatos , Endorfinas/antagonistas & inhibidores , Femenino , Inyecciones Intraventriculares , Masculino , Receptores Opioides/efectos de los fármacos , Factores de Tiempo , betaendorfinaRESUMEN
Arginine vasopressin (AVP) has been reported to have an antipyretic effect in the ewe and guinea pig near term. Perfusions with AVP of sites in the septal region also reduced fever in non-pregnant sheep. In the present experiments adult rabbits with third cerebral ventricular or septal cannulas were restrained in a 23 degree C environment, and rectal temperature was recorded every 10 min. Fever induced by IV administration of leukocytic pyrogen was not reduced by AVP (25-100 ng) given intraventricularly 20 min later. Doses of 1-5 micrograms AVP injected into the septum likewise were not antipyretic but actually caused an increase in fever. This augmentation of the febrile response is consistent with results of previous studies in this laboratory in which AVP increased hyperthermia in a hot environment and enhanced hyperthermic responses to PGE2. The data from these experiments provide no evidence that central AVP is an endogenous antipyretic in rabbits; rather, it may be that central AVP augments fever in this species.
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Antiinflamatorios no Esteroideos , Arginina Vasopresina/farmacología , Temperatura Corporal/efectos de los fármacos , Fiebre/fisiopatología , Interleucina-1 , Animales , Arginina Vasopresina/administración & dosificación , Encéfalo/fisiología , Femenino , Inyecciones Intraventriculares , Cinética , Masculino , Proteínas , ConejosRESUMEN
In previous research the concentration of alpha-MSH within the septal region of rabbits increased with fever. This finding raises the possibility that the septal concentration of this peptide, which reduces fever when given both peripherally and intracerebroventricularly, is important to limitation of fever. To test this idea, rabbits with cannulas in the septal region were made febrile by IV injections of leukocytic pyrogen (LP). Injection of alpha-MSH (1 microgram bilaterally) into the septal region did reduce fever, consistent with the idea that the increase in septal alpha-MSH concentration which occurs naturally in fever limits the febrile response. We also noted late rises in body temperature when experimental and control septal injections were given close together in time. These increases in temperature were similar to those known to occur after injections into the primary temperature control in the PO/AH region. This commonality further strengthens the possibility that septal neurons are important to central modulation of body temperature.
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Antiinflamatorios no Esteroideos/farmacología , Temperatura Corporal/efectos de los fármacos , Interleucina-1 , Hormonas Estimuladoras de los Melanocitos/farmacología , Animales , Femenino , Fiebre/fisiopatología , Cinética , Masculino , Hormonas Estimuladoras de los Melanocitos/administración & dosificación , Proteínas , ConejosRESUMEN
CRF injected into the third cerebral ventricle (0.5-2.5 micrograms) caused dose-related reductions in fever induced in rabbits by IV administration of leukocytic pyrogen. Control injections of CRF when the same animals were afebrile did not alter normal body temperature. Intravenous injections of 5 and 20 micrograms CRF, doses known to release ACTH and corticosteroids into the bloodstream in other species, did not reduce fever. CRF injected into the cerebral ventricles may be antipyretic per se, or it may reduce fever by virtue of central release of the antipyretic peptides ACTH and alpha-MSH.
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Antiinflamatorios no Esteroideos , Hormona Liberadora de Corticotropina/farmacología , Animales , Ventrículos Cerebrales/efectos de los fármacos , Hormona Liberadora de Corticotropina/administración & dosificación , Endotoxinas , Fiebre/fisiopatología , Inyecciones Intraventriculares , Masculino , Hormonas Estimuladoras de los Melanocitos/farmacología , Conejos , Salmonella typhi , Factores de TiempoRESUMEN
Piezoelectric pumps or "jets" are used in industry for precise dispensing of small volumes of fluids. In the present work we have tested the feasibility of using these piezoelectric devices for dispensing fluids in neurobiological research. In one experiment, 70 picoliter (pl) droplets of histochemical reagent were jetted onto discrete targets of frozen tissue sections, and qualitative and quantitative histochemical studies were done on the small (170 microns diameter) circle of tissue wet by the droplets. In the second experiment, 70 pl droplets of neuroactive drugs were jetted onto brain tissue slices while recording single neurons extracellularly in vitro, and the effects of the drugs were found to vary systematically as a function of the number of drops and the distance between drop application and the recorded neuron. The results indicate that piezoelectric jets could have wide application for dispensing fluids in neurobiological research.