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1.
Spinal Cord ; 51(4): 300-5, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23295469

RESUMEN

STUDY DESIGN: Cross-sectional study. OBJECTIVES: To examine predictors of oral health in people with spinal cord injury (SCI). METHODS: Ninety-two people with SCI (> or =6 months, 44% cervical level) completed questionnaires and underwent oral examination. Socio-economic, injury-related and oral habits variables were used for predicting oral health score (OHS); Decayed, missing and filled teeth (DMFT) score; and periodontal screen and recording index (PSR). RESULTS: Most people with SCI were able to bring at least one hand to the mouth (82%) and brush teeth independently (65%). Regarding daily oral habits, 84% reported brushing teeth, 48% rinsing mouth, 14% flossing, 33% tobacco use and 13% mouthstick use. Only 32% had teeth cleaned within the past year. Oral examination revealed three decayed and eight missing teeth on average, with prominent periodontal disease (64%). Employment before SCI and more risky oral habits were significant predictors of worse OHS (P=0.005 and P=0.014, respectively) and PSR score (P=0.010 and P=0.035, respectively). Older age was the only predictor of worse DMFT score (P<0.001). CONCLUSION: Oral health appears compromised in people with SCI. Identification of modifiable risk factors warrants examination whether intervention with focus on behavioral changes may improve oral health in this population.


Asunto(s)
Conductas Relacionadas con la Salud , Enfermedades de la Boca/diagnóstico , Enfermedades de la Boca/etiología , Salud Bucal , Traumatismos de la Médula Espinal/complicaciones , Adolescente , Adulto , Anciano , Distribución de Chi-Cuadrado , Encuestas de Salud Bucal , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Traumatismos de la Médula Espinal/psicología , Traumatismos de la Médula Espinal/rehabilitación , Encuestas y Cuestionarios , Adulto Joven
2.
J Exp Med ; 134(6): 1403-16, 1971 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-4108324

RESUMEN

We have examined human leukocyte preparations for the presence of surface-bound IgE by electron microscopy. Basophil-enriched leukocytes were reacted with burro anti-IgE, a hybrid antibody to burro IgG and ferritin, and ferritin, with or without prior incubation of the cells with an IgE myeloma protein. In the absence of preincubation with IgE small amounts of ferritin were fixed to the surface of basophils but on no other cells. When cells were preincubated with IgE the amount of ferritin fixation on the basophils was markedly increased and a small amount of ferritin was also bound to platelets but again to no other leukocytes. The distribution of ferritin on the basophil surface appeared dependent upon the temperature at which the cells were kept during and after reaction with the various reagents. Basophil sections from cells kept at 0 degrees C had ferritin bound to the surface membrane in patches distributed around the entire circumference. Basophil sections from cells prepared at room temperature had ferritin distributed assymetrically covering a surface membrane segment one-fifth to one-half of the circumference. In control studies in which monomeric IgG was substituted for the IgE and burro anti-IgG was used instead of burro anti-IgE, no cellular fixation of ferritin was observed.


Asunto(s)
Basófilos/inmunología , Membrana Celular/inmunología , Inmunidad Celular , Inmunoglobulinas/análisis , Animales , Anticuerpos Antiidiotipos , Reacciones Antígeno-Anticuerpo , Basófilos/citología , Cromatografía en Gel , Ferritinas/antagonistas & inhibidores , Liberación de Histamina , Humanos , Inmunoglobulina E/análisis , Inmunoglobulina G/antagonistas & inhibidores , Técnicas In Vitro , Microscopía Electrónica , Perisodáctilos , Pruebas de Precipitina , Unión Proteica
3.
Sci Total Environ ; 698: 134306, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31783449

RESUMEN

In this study, solid state 13C nuclear magnetic resonance (NMR) spectroscopy was used to explore the carbon-containing functional groups present in pyrogenic carbon (PyC) produced during different fire spread modes to forest litter fuels from a dry sclerophyll eucalypt forest burnt in a combustion wind tunnel. A replicated experimental study was performed using three different fire spread modes: heading fires (i.e. fires which spread with the wind), flanking fires (i.e. fires which spread perpendicular to the wind) and backing fires (i.e. fires which spread against the wind). In addition to 13C NMR measurements of PyC, detailed fire behaviour measurements were recorded during experiments. Experiments showed that heading fires produced significantly more aryl carbon in ash samples than flanking fires. All other experimental comparisons for burnt fuel samples involving different fire spread modes were statistically insignificant. Principal component analysis (PCA) was used to explore the relationship between 13C NMR functional groups and fire behaviour observations. Results from PCA indicate that maximising the residence time of high temperature combustion and the combustion factor (i.e. the fraction of pre-fire biomass consumed by fire) could be a method for increasing the amount of aryl carbon in PyC. Maximising the amount of aryl carbon could be beneficial for the overall PyC balance from fire, since more recalcitrant carbon (e.g. carbon with a higher aryl carbon content) that is not emitted to the atmosphere has been shown to have longer residence times in environmental media such as soils or sediments.

4.
Science ; 189(4196): 13-7, 1975 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-17759725

RESUMEN

A system of primary wildland reserves may be required to ensure a diversity of plant and animal species in the future. A strategy for locating such reserves involves considerations of their location, number, size, and linkage. The equilibrium theory of island biogeography is a useful analytical tool for predicting future biogeographies according to the dynamics of present plant and animal distributions. Existing reserves in the United States are inadequate in size and number and are clumped in one geographic region. In a planned network there might be several levels of reserves, starting with first- and second-order watersheds of large enough size to support a stable population of large carnivores. Reserves should be distributed so that they include a maximum of the world's biological diversity. Lower-order reserves might serve as stepping-stones among which a supply of species might move as a kind of distributed storage and reintroduce themsleves when local instabilities occur. This would maintain a high immigration rate to balance an extinction rate which can only increase as human settlements expand.

5.
Eur Respir J ; 32(4): 1047-52, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18508829

RESUMEN

The present study identified three patients with bronchiectasis receiving inhaled corticosteroids (ICSs) who had symptomatic adrenal suppression secondary to ICS. The prevalence of adrenal suppression is unknown in bronchiectasis. The frequency of adrenal suppression and the impact of ICS use in bronchiectasis patients were examined. In total, 50 outpatients (33 receiving ICSs) underwent a short Synacthen test and completed a St George's Respiratory Questionnaire (SGRQ). Symptoms of adrenal suppression, steroid use and lung function were compared between subjects who were suppressed and those who were not. Adrenal suppression was evident in 23.5% of subjects who did not receive ICSs and 48.5% of those who did. Basal cortisol and the increments by which cortisol increased 30 min after Synacthen were lower in suppressed than in nonsuppressed subjects. The incremental cortisol rise was negatively correlated with SGRQ impacts and total score, suggesting a worse quality of life in those who had an impaired adrenal response. The greatest frequency of generalised symptoms was seen in the suppressed group. A significant proportion of subjects with bronchiectasis have evidence of adrenal suppression, and this is increased when inhaled corticosteroids are also used. Impairment of the cortisol response to stimulation is associated with poorer health status.


Asunto(s)
Corticoesteroides/uso terapéutico , Glándulas Suprarrenales/metabolismo , Bronquiectasia/diagnóstico , Bronquiectasia/tratamiento farmacológico , Administración por Inhalación , Insuficiencia Suprarrenal/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Pulmón/efectos de los fármacos , Masculino , Persona de Mediana Edad , Esteroides/uso terapéutico , Resultado del Tratamiento
7.
J Clin Invest ; 50(6): 1167-80, 1971 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-5578228

RESUMEN

A method is described for assessing the in vivo oxygen consumption and lactate production rates of human knee joints. It is based on the rate of fall of P(o2) and the rate of rise in lactate concentration in an intra-articular saline pool after interruption of the circulation to the joint with an arterial tourniquet. Studies in 5 control patients with degenerative joint disease and 29 patients with rheumatoid arthritis showed a 2- to 3-fold higher mean oxygen uptake rate and a 10- to 12-fold higher mean lactate appearance rate in the saline in the rheumatoid joints with severe disease compared to the control joints. These metabolic variables correlated with tissue metabolic demand as estimated in synovial biopsies. (133)Xe washout from the intra-articular space, which reflects joint circulatory flow, showed a 3-fold greater mean washout rate from the rheumatoid joints (48 studies) than control joints (7 studies) with extensive overlap between the two groups. (133)Xe washout rate correlated with knee joint inflammation estimated both clinically and histologically. After synovectomy in four patients, the operated knee showed a greater fall in lactate production than the opposite knee in three of these patients. Neither knee joint oxygen uptake nor (133)Xe washout rate changed significantly. Intra-articular corticosteroid injection (eight patients) resulted in decreased lactate production and a decreased (133)Xe washout rate in the injected knee and variable results in the untreated knee. Oxygen uptake again was unchanged after therapy.


Asunto(s)
Artritis Reumatoide/metabolismo , Articulación de la Rodilla/metabolismo , Lactatos/biosíntesis , Consumo de Oxígeno , Adulto , Anciano , Semivida , Humanos , Recuento de Leucocitos , Metilprednisolona/uso terapéutico , Persona de Mediana Edad , Presión Parcial , Sinovectomía , Xenón
8.
Nat Commun ; 7: 11536, 2016 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-27146785

RESUMEN

Vegetation fires are a complex phenomenon in the Earth system with many global impacts, including influences on global climate. Estimating carbon emissions from vegetation fires relies on a carbon mass balance technique that has evolved with two different interpretations. Databases of global vegetation fire emissions use an approach based on 'consumed biomass', which is an approximation to the biogeochemically correct 'burnt carbon' approach. Here we show that applying the 'consumed biomass' approach to global emissions from vegetation fires leads to annual overestimates of carbon emitted to the atmosphere by 4.0% or 100 Tg compared with the 'burnt carbon' approach. The required correction is significant and represents ∼9% of the net global forest carbon sink estimated annually. Vegetation fire emission studies should use the 'burnt carbon' approach to quantify and understand the role of this burnt carbon, which is not emitted to the atmosphere, as a sink enriched in carbon.

9.
Cornea ; 13(4): 294-304, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7924328

RESUMEN

Three corneoscleral discs (from two donors) underwent subtotal endothelial loss during routine "long-term" organ culture storage. Laboratory studies of these corneas revealed evidence of herpes simplex virus (HSV) infection. The fellow cornea from one of the donors had been issued for transplant to a patient with keratoconus. Deterioration of the graft was noted 5 days after surgery; the disc was removed at 2 months and was shown to be infected with HSV. In an experiment designed to simulate initial "cleansing" of donor globes, 0.1% polyvinylpyrolidone-iodine protected cells from infection with HSV. It was concluded that the detection of HSV in these corneas could not be explained by external contamination of the ocular surface. Furthermore, culture of conjunctival and pharangeal swabs taken from 47 consecutive donors confirmed that HSV is rarely isolated at or around the time of death. Five pairs of donor corneas destined for use in transplantation were selected at random and investigated for the presence of HSV. HSV DNA was detected by polymerase chain reaction (PCR) in tissue from two of the corneal donors. Sequential stepwise sectioning suggested that HSV DNA when present was distributed in discrete foci within the cornea. These observations suggest that HSV infection may be a cause of severe endothelial loss during corneal organ culture and possibly provide an explanation for some "failures" of corneal grafting.


Asunto(s)
Córnea/virología , ADN Viral/análisis , Herpesvirus Humano 1/aislamiento & purificación , Queratitis Herpética/transmisión , Donantes de Tejidos , Adulto , Anciano , Antígenos Virales/análisis , Córnea/patología , Trasplante de Córnea , Femenino , Rechazo de Injerto/patología , Rechazo de Injerto/virología , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/inmunología , Humanos , Queratitis Herpética/patología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
10.
J Holist Nurs ; 19(2): 102-21; quiz 122-6, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11847834

RESUMEN

Adolescents are considered at high risk for engaging in such negative health behaviors as drug and alcohol use, unprotected sexual intercourse, and violence. Conventional wisdom has long upheld the belief that the peer group exerts the strongest influence on adolescent behavior. However, recent research has shown that in fact the family remains a strong factor in moderating teen risk behavior. Holistic nursing acknowledges the crucial relationship between environment and health; the environment is composed of everything that surrounds the individual, which by definition includes the family. The purpose of this article is to examine the evidence supporting the concept of the family as a protective external asset in adolescent development, to explore the way the family helps defend young people from risk, and to review briefly the implications for nursing research, practice, advocacy, and education.


Asunto(s)
Conducta del Adolescente , Relaciones Familiares , Desarrollo de la Personalidad , Psicología del Adolescente , Adolescente , Humanos , Factores de Riesgo , Medio Social , Trastornos Relacionados con Sustancias/prevención & control , Estados Unidos , Violencia/prevención & control
17.
Cancer ; 43(1): 329-42, 1979 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-367571

RESUMEN

We have studied ten patients with a lymphoproliferative disorder characterized by massive splenomegaly; minimal lymphadenopathy; varying degrees of blood cytopenias; circulating atypical lymphoid cells frequently with "hairy" cytoplasm; monoclonal serum paraprotein; and tartrate-resistant acid phosphatase reactivity in the tumor cells of five patients tested. Although the clinical and laboratory features in most cases prompted a clinical diagnosis of "hairy cell leukemia" (HCL), histologic, ultrastructural and immunohistologic studies of multiple organs revealed distinctive features recognizably different from leukemic reticuloendotheliosis (LRE). Because this B lymphocyte proliferation may be mistaken for LRE in cases where careful histologic study is not performed, it may be responsible in part for the conflicting data in attempts to characterize the cell of origin of the latter disease. Clinical and experimental data in HCL must be questioned if they do not include histopathologic confirmation of the diagnosis.


Asunto(s)
Leucemia de Células Pilosas/diagnóstico , Linfoma no Hodgkin/diagnóstico , Fosfatasa Ácida/metabolismo , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Inmunoglobulina M , Leucemia de Células Pilosas/sangre , Ganglios Linfáticos/patología , Linfoma no Hodgkin/sangre , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Esplenomegalia/patología , Tartratos
18.
J Cell Sci ; 31: 165-78, 1978 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-670318

RESUMEN

Erythropoietic cells of 5 species, including man, contain endoplasmic reticulum present as individual cisternae or tubules scattered throughout the cytoplasm of all stages except mature RBCs. The endoplasmic reticulum is mainly agranular but occurs frequently as a variant of granular ER which is characterized by an asymmetrical and irregular distribution of ribosomes along one cytoplasmic face. In most cells, the endoplasmic reticulum occurs in close proximity to mitochondria or the plasma membrane , suggesting that the organelle may be involved in functions related to these structures, e.g. haem biosynthesis. Endoplasmic reticulum is more abundant in early than in late erythroid cells. Its exact role in RBC development is unclear. Since endoplasmic reticulum could account for 'plasma membrane-bound ribosomes' reported in lysed reticulocytes, studies were performed which ruled out this possibility and which suggested that such ribosomes were an artifact of the lysing conditions. Hypotonic lysis in less than 20 vol. of magnesium-containing buffers yielded ghosts variably contaminated by ribosomes and other structures. Lysis of reticulocytes in 20-30 vol. of magnesium-free buffer or homogenization of whole cells or crude membrane fractions in hypotonic buffer removed virtually all contaminating ribosomes from the purified membrane fraction.


Asunto(s)
Retículo Endoplásmico/ultraestructura , Eritroblastos/ultraestructura , Eritrocitos/ultraestructura , Ribosomas/ultraestructura , Animales , Gatos/anatomía & histología , Membrana Celular/ultraestructura , Humanos , Microscopía Electrónica , Conejos/anatomía & histología , Ratas/anatomía & histología , Reticulocitos/ultraestructura , Salamandridae/anatomía & histología
19.
Br J Haematol ; 31(2): 135-48, 1975 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1201233

RESUMEN

Marrow aspirates from sickle cell patients were examined without prior deoxygenation and revealed the presence of a variable proportion (10-30%) of sickled red cells and reticulocytes. The main feature of sickled red cells was the presence of 17.6 nm fibres arranged in hexagonal order, and to a lesser extent in square or rectangular array, to form bundles of varying size and compactness which occupied the entire cytoplasm. The sickling pattern in reticulocytes was more variable. Some reticulocytes contained highly-ordered bundles of 17.6 nm fibres whose structure and distribution was identical to that in red cells from whiich they could be distinguished only by their content of organelles. Many reticulocytes exhibited less-organized fibre patterns ranging from localized aggregates to poorly-ordered regions of short fibres and filaments lacking apparent preferential orientation. In these cells, the bulk of the cytoplasm was not polymerized. Haemoglobin polymerization in reticulocytes led to entrapment of ribosomes in concentrated foci among the fibres. Frequently, iron-laden mitochondria were associated with sickled reticulocytes. The variation in pattern of sickling seen in reticulocytes is attributed to possible differences in concentration of Hb S. Correlative studies have shown that fibres were not induced by fixation procedures. Marked phagocytic degradation of sickled cells by macrophages was observed. The results are interpreted to indicate the possible intramedullary phagocytosis of red cells and reticulocytes, predisposed to sickling in the marrow. However, the data are also consistent with the removal of sickled elements from the circulating blood.


Asunto(s)
Anemia de Células Falciformes/patología , Células de la Médula Ósea , Médula Ósea/ultraestructura , Eritrocitos Anormales/ultraestructura , Fagocitosis , Reticulocitos/ultraestructura , Humanos , Macrófagos/ultraestructura
20.
Br J Haematol ; 31(3): 381-9, 1975 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1201249

RESUMEN

Electron microscopic studies of bone marrow aspirates obtained from patients with homozygous sickle cell anaemia (HbSS) were fixed immediately without attempts to deoxygenate the samples. Erythroblasts and normoblasts in these preparations were devoid of haemoglobin polymers or other indications of sickling. Furthermore, the nucleated erythroid cells from sickle-cell patients presented an ultrastructural morphology indistinguishable from that of identically-processed erythroid cells in marrow samples from normal human volunteers. This report presents a description of the ultrastructural features of pronormoblasts and normoblasts in normal and sickle-cell marrows and stresses the essentially normal appearance of nucleated erythroid elements in sickle cell anaemia. Exposure of sickle-cell marrow aspirates to nitrogen at 37 degrees C for 30 min resulted in haemoglobin polymerization in most erythrocytes and reticulocytes but only in 10-20% of the nucleated erythroid cells. Haemoglobin polymers in the form of intertwining fibre meshworks were observed in reticulocytes, orthochromatic and polychromatophilic normoblasts, but were absent in basophilic normoblasts and pronormoblasts. The results suggest that the concentration of haemoglobin in intramedullary normoblasts may be the limiting factor determining the predisposition of these cells to undergo sickling as well as the pattern of haemoglobin aggregation. Under the physiological conditions prevailing in the marrow, haemoglobin concentration in normoblasts may be insufficient to result in aggregation and polymerization.


Asunto(s)
Anemia de Células Falciformes/patología , Células de la Médula Ósea , Médula Ósea/ultraestructura , Eritroblastos/ultraestructura , Eritrocitos/ultraestructura , Núcleo Celular/ultraestructura , Cromatina/ultraestructura , Citoplasma/ultraestructura , Eritroblastos/fisiopatología , Eritrocitos Anormales/ultraestructura , Hemoglobinas , Humanos , Nitrógeno/fisiología , Polímeros , Reticulocitos/ultraestructura
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