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1.
Br J Cancer ; 115(5): 571-8, 2016 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-27441495

RESUMEN

BACKGROUND: The addition of hypoxia modifiers carbogen and nicotinamide (CON) to radiotherapy (RT) improved overall survival (OS) in bladder cancer patients in the BCON phase III clinical trial. We investigate whether expression of hsa-miR-210 in BCON patient samples reflects hypoxia and predicts benefit from hypoxia modification. METHODS: In all, 183 T1-T4a bladder cancer samples were available for miR-210 analysis. A total of 86 received RT+CON and 97 received RT alone. TaqMan qPCR plates were used to assess miR-210 expression. Patients were classified as low (

Asunto(s)
Hipoxia de la Célula/genética , MicroARNs/genética , Neoplasias de la Vejiga Urinaria/genética , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Vejiga Urinaria/patología
2.
Plant Biol (Stuttg) ; 26(4): 499-507, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38773740

RESUMEN

Global crop production in agriculture depends on water availability. Future scenarios predict increasing occurrence of flash floods and rapidly developing droughts accompanied by heatwaves in humid regions that rely on rain-fed agriculture. It is challenging to maintain high crop yields, even in arid and drought-prone regions that depend on irrigation. The average water demand of crops varies significantly, depending on plant species, development stage, and climate. Most crops, such as maize and wheat, require relatively more water during the vegetative phase compared to the ripening phase. In this review, we explain WUE and options to improve water use and thus crop yield. Nutrient management might represent another possibility to manipulate water uptake and use by plants. An emerging topic involves agroforest co-cultivation, where trees in the system facilitate water transfer through hydraulic lift, benefiting neighbouring crops. Other options to enhance crop yield per water use are discussed.


Asunto(s)
Productos Agrícolas , Agua , Productos Agrícolas/fisiología , Productos Agrícolas/crecimiento & desarrollo , Agua/metabolismo , Riego Agrícola , Sequías , Agricultura/métodos , Producción de Cultivos/métodos
3.
J Exp Med ; 187(12): 2045-53, 1998 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-9625764

RESUMEN

Different strains of mice have varying susceptibilities to ultraviolet radiation (UV) of wavelength 280-320 nm (UVB) for 50% suppression of systemic contact hypersensitivity (CHS) responses. Prevalence of histamine-staining dermal mast cells in different strains of mice (C57BL/ 6J, DBA/2, BALB/c) correlated directly with their susceptibility to UVB-induced systemic immunosuppression. BALB/c mice carrying Uvs1, a major locus for susceptibility to UV-induced immunosuppression, contained greater numbers of dermal mast cells than BALB/c mice of the same parental origin. Strains of mice that were differentiated on their susceptibility to UVB-induced downregulation of systemic CHS responses were similar in their susceptibility to histamine-induced immunomodulation. Histamine, but not UVB irradiation, decreased systemic CHS responses in mast cell-depleted mice (W f/W f). Reconstitution of the dorsal skin of W f/W f mice with bone marrow-derived mast cell precursors from nonmutant mice rendered the mice susceptible to UVB irradiation for systemic suppression of CHS responses. UVB irradiation did not suppress delayed type hypersensitivity responses to allogeneic spleen cells in W f/W f mice. In contrast, UV irradiation suppressed CHS responses in W f/W f mice when hapten was applied to the irradiated site. This study demonstrates that dermal mast cells are necessary for the induction of systemic suppression of CHS responses by UVB radiation, and suggests that mast cell- derived histamine is one component of this UVB-induced systemic immunosuppression.


Asunto(s)
Dermatitis por Contacto/inmunología , Terapia de Inmunosupresión , Mastocitos/inmunología , Piel/inmunología , Rayos Ultravioleta , Animales , Células de la Médula Ósea , Femenino , Hipersensibilidad Tardía/inmunología , Hipersensibilidad Tardía/prevención & control , Mastocitos/efectos de la radiación , Mastocitos/trasplante , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Microscopía por Video , Tolerancia a Radiación , Piel/efectos de la radiación , Trasplante de Células Madre
4.
Orthop Nurs ; 36(2): 147-152, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28358779

RESUMEN

Osteoporosis affects more than 44 million individuals in the United States annually while disease management continues to fall short of the recommended guidelines. This study institutes a practice change for osteoporosis/osteopenia screening and treatment founded on current evidence-based guidelines. A retrospective chart review was evaluated for current trends in the identification and treatment of osteoporosis/osteopenia in female patients older than 65 years. Data were then compared with identical data collected after implementing an evidence-based osteoporosis guideline tool. Quantitative analysis indicated poor adherence of established osteoporosis guidelines by providers. In comparison, after implementation of the osteoporosis treatment guideline tool, there was an improvement of more than 40% in the identification and treatment of osteoporosis/osteopenia. Utilization of the evidence-based osteoporosis guideline tool resulted in quality improvement in identifying and treating those with or at risk for osteoporosis/osteopenia.


Asunto(s)
Práctica Clínica Basada en la Evidencia , Osteoporosis/diagnóstico , Osteoporosis/terapia , Mejoramiento de la Calidad , Anciano , Femenino , Adhesión a Directriz , Humanos , Tamizaje Masivo/métodos , Estudios Retrospectivos , Servicios de Salud Rural , Estados Unidos
5.
J Natl Cancer Inst ; 64(6): 1363-72, 1980 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6929375

RESUMEN

Some biologic, hematologic, and immunologic aspects of the growth and metastasis of the MC-2 fibrosarcoma indicated its suitability as a model for the study of lymphogenous metastasis. The tumor was maintained in syngeneic female BALB/c mice by the serial sc passage of 10(5) viable tumor cells. It metastasized macroscopically in all mice to regional lymph nodes (RLN) and to the lungs. Both forward and retrograde node-to-node metastases were found. Tumor growth and metastasis were associated with splenomegaly, thymus atrophy, cachexia, neutrophilia, lymphopenia, and anemia. Tumor excision at various times after inoculation showed that all mice whose tumors were excised when there was histologic evidence of metastasis in all RLN (day 13; mean of tumor wt, 122 mg) died subsequently from metastases, whereas no animals died whose tumors were excised on or before day 8 (mean of tumor wt, 15 mg). The onset of metastasis was seen in some RLN on day 8. All survivors were immune to challenge with 10(5) viable tumor cells, which demonstrated the immunogenicity of the tumor. Concomitant tumor immunity could be demonstrated prior to the onset of metastasis (days 6 and 7) but not early (days 0--2) or late (days 15, 19, and 20) in primary-site tumor growth. The early immune response to the tumor demonstrable as concomitant tumor immunity appeared to be abrogated by the progressive growth and metastasis of the neoplasm. Tumor cells passaged in adult thymectomized, X-irradiated, syngeneic recipients produced larger RLN metastases and smaller primary tumors than those passaged in control mice.


Asunto(s)
Modelos Animales de Enfermedad , Fibrosarcoma/patología , Metástasis Linfática , Neoplasias Experimentales/patología , Animales , Tolerancia Inmunológica , Leucocitos/patología , Neoplasias Pulmonares/secundario , Ratones , Trasplante de Neoplasias , Timectomía
6.
J Mol Biol ; 295(1): 105-15, 2000 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-10623511

RESUMEN

Ribonuclease P (RNaseP) catalyses the removal of the 5'-leader sequence from pre-tRNA to produce the mature 5' terminus. The prokaryotic RNaseP holoenzyme consists of a catalytic RNA component and a protein subunit (RNaseP protein), which plays an auxiliary but essential role in vivo by binding to the 5'-leader sequence and broadening the substrate specificity of the ribozyme. We determined the three-dimensional high-resolution structure of the RNaseP protein from Staphylococcus aureus (117 amino acid residues) by nuclear magnetic resonance (NMR) spectroscopy in solution. The protein has an alphabeta-fold, similar to the ribonucleoprotein domain. We used small nucleic acid molecules as a model for the 5'-leader sequence to probe the propensity for generic single-stranded RNA binding on the protein surface. The NMR results reveal a contiguous interaction site, which is identical with the previously identified leader sequence binding site in RNaseP holoenzyme. The conserved arginine-rich motif does not bind single-stranded RNA. It is likely that this peptide segment binds selectively to double-stranded sections of P RNA, which are conformationally more rigid. Given the essentiality of RNaseP for the viability of the organism, knowledge of the S. aureus protein structure and insight into its interaction with RNA will help us to develop RNaseP and RNaseP protein as targets for novel antibiotics against this pathogen.


Asunto(s)
Endorribonucleasas/química , Endorribonucleasas/metabolismo , ARN Catalítico/química , ARN Catalítico/metabolismo , ARN/metabolismo , Staphylococcus aureus/enzimología , Secuencia de Aminoácidos , Sitios de Unión , Secuencia Conservada , Endorribonucleasas/genética , Modelos Moleculares , Datos de Secuencia Molecular , Peso Molecular , Resonancia Magnética Nuclear Biomolecular , Estructura Secundaria de Proteína , ARN/síntesis química , ARN/genética , ARN Catalítico/genética , Ribonucleasa P , Alineación de Secuencia , Soluciones , Staphylococcus aureus/genética , Electricidad Estática , Especificidad por Sustrato , Volumetría
7.
J Leukoc Biol ; 57(6): 909-18, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7540642

RESUMEN

To investigate the regulatory effects of the prototypic Th2 lymphocyte products and potential immunotherapeutic agents interleukin-4 (IL-4) and IL-10 on macrophages differentiated in vitro under different cytokine-defined environments, blood monocytes were incubated for 7 days in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF), macrophage colony-stimulating factor or IL-4. The effect of monocyte culture in the presence or absence of serum was also investigated. Functional responses by 7-day-cultured cells to IL-4, quantified as decreased CD14 expression and suppression of lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha (TNF-alpha) and IL-1 beta production, and as a positive response, increased CD23 expression, were compared directly with the responses by monocytes from which they were derived. In response to IL-10, decreases in LPS-induced TNF-alpha and IL-1 beta production and reduction in the expression of major histocompatibility complex (MHC) class II antigens were examined. Seven-day cultured monocytes/macrophages showed (1) diminished TNF-alpha production in response to IL-10 but not IL-4 (2), diminished IL-1 beta production in response to both IL-4 and IL-10, and compared with fresh monocytes (3), diminished CD14 expression in response to IL-4, and (4) a lesser increase in CD23 expression in response to IL-4. This was the case regardless of the cytokine in the presence of which the cells had been cultured for 7 days. Monocytes cultured for 7 days in GM-CSF expressed increased levels of MHC class II and LPS-induced TNF-alpha and responded inefficiently to IL-10 for decreased MHC class II. The responses by monocytes cultured for 7 days with GM-CSF resemble the published properties of synovial fluid macrophages from patients with chronic inflammatory arthritis. The study highlights the complexity of monocyte/macrophage responses to the immunoregulatory cytokines IL-4 and IL-10 and concludes that responses to IL-4 and IL-10 by blood monocytes may not be representative of responses by their differentiated or activated counterparts.


Asunto(s)
Interleucina-10/farmacología , Interleucina-4/farmacología , Monocitos/efectos de los fármacos , Antígenos CD/análisis , Antígenos de Diferenciación Mielomonocítica/análisis , Células Cultivadas , Antígenos de Histocompatibilidad Clase II/análisis , Humanos , Interleucina-1/biosíntesis , Interleucina-4/metabolismo , Receptores de Lipopolisacáridos , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Monocitos/inmunología , Monocitos/metabolismo , Receptores de IgE/análisis , Factor de Necrosis Tumoral alfa/biosíntesis
8.
J Leukoc Biol ; 53(3): 309-19, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7681094

RESUMEN

To gain insight into the factors regulating an inflammatory response in vivo, the activities of peritoneal macrophages and the influence of the inflammatory fluids from which they were harvested were studied in continuous ambulatory peritoneal dialysis (CAPD) patients with peritonitis. Specifically, the production of tumor necrosis factor alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and prostaglandin E2 (PGE2) by lipopolysaccharide-stimulated human peritoneal macrophages from CAPD patients with peritonitis was examined in the presence of the inflammatory dialysates from which they were isolated. When tested at a dilution of 20%, the dialysates inhibited production of TNF-alpha, a key monokine in the orchestration of the inflammatory response. In contrast to the effect on TNF-alpha, the dialysates did not affect IL-1 beta production by stimulated macrophages. The activity inhibitory for TNF-alpha synthesis was not fully characterized, but a number of known inhibitors were shown not to be responsible for the suppressive activity. The inhibitory activity was detected in cases of noninfective peritonitis and excluded the possibility that a bacterial product was responsible. Hyperosmolality, pH, protein levels, glucose, uremic molecules, cortisol, heparin, and antibiotics were not responsible for the inhibitory activity. The activity had some similarity to the reported actions of alpha-globulins (which are acute phase proteins), PGE2, TNF-alpha soluble receptors, and IL-6, but there was no evidence for their involvement. Whether the selective suppression of TNF-alpha production is a general finding in inflammatory responses will require additional studies. This study nevertheless illustrates the potential for the host to regulate tightly the development of an excessive inflammatory response and thus to limit tissue pathology. However, it is unknown whether an appropriate host defense is compromised.


Asunto(s)
Interleucina-1/biosíntesis , Macrófagos/metabolismo , Cavidad Peritoneal/citología , Diálisis Peritoneal Ambulatoria Continua , Peritonitis , Factor de Necrosis Tumoral alfa/biosíntesis , Proteínas de Fase Aguda/farmacología , Corteza Suprarrenal/metabolismo , Antibacterianos/farmacología , Actividad Bactericida de la Sangre/efectos de los fármacos , Creatinina/análisis , Dinoprostona/metabolismo , Glucosa/farmacología , Heparina/farmacología , Humanos , Hidrocortisona/metabolismo , Concentración de Iones de Hidrógeno , Interleucina-6/farmacología , Concentración Osmolar , Diálisis Peritoneal Ambulatoria Continua/efectos adversos , Peritonitis/etiología , Proteínas/análisis , Receptores de Superficie Celular/fisiología , Receptores del Factor de Necrosis Tumoral , Urea/análisis , Uremia/metabolismo , Ácido Úrico/análisis
9.
J Leukoc Biol ; 66(4): 583-7, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10534113

RESUMEN

Abscess formation has been viewed as a host defense strategy to contain the spread of infection. However, abscesses are also serious and life-threatening manifestations of persisting microbial infection. The initiation of abscess formation, both clinically and experimentally, involves the release of bacteria and an abscess-potentiating agent (e.g., fecal fiber or an analog) into a sterile site, with host defense mechanisms being unable to eliminate the infecting organisms. Abscess formation is aided by a combination of factors that share a common feature: impairment of phagocytic killing and hence clearance of microorganisms. These include bacterial virulence factors (e.g., capsule formation, succinic acid production); complement activation by the abscess potentiating agent; fibrin deposition; and microbial sequestration within abscess neutrophils. Recruitment of cells into the peritoneal cavity follows mast cell activation in the pathogenesis of infection: histamine and tumor necrosis factor alpha can be detected in the peritoneal cavity within minutes of challenge with an abscess-inducing mixture. However, the role of mast cells in host defense is made less clear by the finding of diminished abscess formation (but no mortality or increased morbidity) in mast-cell-depleted mice. This may indicate that mast cell products have a role in not only the initiation of an inflammatory response but also the promotion of fibrin deposition and abscess formation.


Asunto(s)
Absceso Abdominal/etiología , Sepsis/etiología , Absceso Abdominal/inmunología , Absceso Abdominal/microbiología , Absceso Abdominal/patología , Animales , Modelos Animales de Enfermedad , Fibrina/metabolismo , Humanos , Inflamación , Mastocitos/inmunología , Ratones , Sepsis/inmunología , Sepsis/microbiología , Sepsis/patología , Factores de Tiempo
10.
J Leukoc Biol ; 66(4): 575-8, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10534111

RESUMEN

The primary interleukin-4 (IL-4) receptor complex on monocytes (type I IL-4 receptor) includes the 140-kDa alpha chain (IL-4R alpha) and the IL-2 receptor gamma chain, gamma(c), which heterodimerize for intracellular signaling, resulting in suppression of lipopolysaccharide (LPS)-inducible inflammatory mediator production. The activity of IL-13 on human monocytes is very similar to that of IL-4 because the predominant signaling chain (IL-4R alpha) is common to both receptors. In fact, IL-4R alpha with IL-13R alpha1 is designated both as an IL-13 receptor and the type II IL-4 receptor. When the anti-inflammatory activities of IL-4 and IL-13 were investigated on synovial fluid macrophages and compared with the responses by monocytes isolated from the patients at the same time as joint drainage, the response profiles differed with some responses similar in the two cell populations, others reduced on the inflammatory cells. Similar differences were recorded in the response profiles to IL-4 and IL-13 by monocytes and monocytes cultured for 7 days in macrophage colony-stimulating factor (M-CSF) or granulocyte-macrophage CSF (GM-CSF) (monocyte-derived macrophages, MDMac). MDMac have reduced gamma(c) mRNA levels and reduced expression of the functional 64-kDa gamma(c). There was a similar loss of IL-13R alpha1 mRNA on monocyte differentiation. In turn, there was a significant reduction in the ability of IL-4 and IL-13 to activate STAT6. These findings suggest that different functional responses to IL-4 and IL-13 by human monocytes and macrophages may result from reduced expression of gamma(c) and IL-13R alpha1.


Asunto(s)
Interleucina-13/inmunología , Interleucina-4/inmunología , Macrófagos/inmunología , Monocitos/inmunología , Diferenciación Celular , Humanos , Subunidad alfa1 del Receptor de Interleucina-13 , Monocitos/citología , Receptores de Interleucina/inmunología , Receptores de Interleucina-13 , Receptores de Interleucina-2/inmunología , Receptores de Interleucina-4/inmunología
11.
Arch Intern Med ; 144(2): 297-300, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6696565

RESUMEN

Intra-abdominal hemorrhage in patients with hemophilia is uncommon but represents a major cause of death in hemophiliacs. The manifestations are protean and may mimic other intra-abdominal processes. We present seven episodes of hemophilic intra-abdominal hemorrhage in which the initial diagnoses were incorrect in five of the seven cases. The mean time from seeking medical assistance to correct diagnoses was two days (range, zero to five days). Computed tomography proved useful, particularly when the diagnosis was uncertain or needed to be differentiated from other possibilities, such as aneurysm, tumor, or abscess. Delay in diagnosis and diagnostic and therapeutic misadventures can be minimized only by a knowledge of the nature of such hemorrhage.


Asunto(s)
Hemoperitoneo/etiología , Hemofilia A/complicaciones , Adulto , Anciano , Errores Diagnósticos , Hemoperitoneo/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Espacio Retroperitoneal/diagnóstico por imagen , Tomografía Computarizada por Rayos X
12.
Cardiovasc Res ; 51(2): 359-67, 2001 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-11470476

RESUMEN

OBJECTIVE: Exercise promotes "sarcoplasmic reticulum (SR) Ca2+ unloading" in porcine coronary smooth muscle, resulting in decreased agonist-induced Ca2+ release. We studied Ca2+ handling in healthy, non-occluded right coronary artery cells from hearts chronically occluded at the circumflex artery. METHODS: Myoplasmic free Ca2+ (Ca(m)) was assessed with fura-2 in cells from sedentary (n=8) and aerobically exercise-trained (n=6) female Yucatan pigs after 6-month circumflex artery ameroid occlusion (OCC) and in cells from non-occluded, sedentary pigs (SED, n=5). First, Ca influx was induced by 80 mM KCl depolarization (priming step) followed by 5 mM caffeine to elicit maximal Ca2+ release and depletion. The SR was Ca-loaded again by depolarization and then exposed to caffeine after 2- or 11-min recovery to compare SR Ca2+ unloading. RESULTS: Baseline Ca(m), caffeine-induced peak Ca(m), and depolarization-induced maximum Ca(m) were decreased, and depolarization-induced time-to-half-maximum was increased in OCC vs. SED pigs, suggesting a tonic Ca2+ buffering (lowering) effect of occlusion. Exercise did not alter these effects. SR Ca2+ unloading occurred only in SED, as evidenced by decreased caffeine-induced Ca2+ release after 11 min of recovery, and was inhibited by low extracellular Na+. CONCLUSIONS: SR Ca2+ unloading can be demonstrated in coronary smooth muscle from sedentary pigs using a novel SR Ca2+ unloading protocol, and Ca2+ unloading partly depends on Na+-Ca2+ exchange activity. Furthermore, SR Ca2+ unloading in cells from non-occluded right coronary arteries of chronically circumflex-occluded pig hearts was not altered by exercise, perhaps due to enhanced tonic Ca2+ extrusion versus cells from normal, sedentary animals.


Asunto(s)
Calcio/metabolismo , Enfermedad Coronaria/metabolismo , Músculo Liso Vascular/metabolismo , Retículo Sarcoplasmático/metabolismo , Adaptación Fisiológica , Análisis de Varianza , Animales , Tampones (Química) , Cafeína/farmacología , Células Cultivadas , Vasos Coronarios/efectos de los fármacos , Femenino , Modelos Animales , Condicionamiento Físico Animal , Cloruro de Potasio/farmacología , Intercambiador de Sodio-Calcio/metabolismo , Porcinos Enanos
13.
J Invest Dermatol ; 117(4): 886-91, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11676828

RESUMEN

Previous studies using an antibody to cis-urocanic acid and mast-cell-depleted mice implicated both cis-urocanic acid and mast cells in the mechanisms by which ultraviolet B light suppresses systemic contact hypersensitivity responses in mice. In the absence of a direct stimulatory effect of cis-urocanic acid on connective tissue mast cells, an indirect association was investigated. A blister induced in the rat hind footpad was used to examine the effects of slowly perfused cis-urocanic acid on cutaneous blood flow. cis-Urocanic acid but not trans-urocanic acid increased microvascular flow by a mechanism largely dependent on the combined activity of the neuropeptides, substance P and calcitonin gene-related peptide. Perfusion of cis-urocanic acid over the base of blisters induced in sensory-neuropeptide-depleted rats did not have any stimulatory effect above that seen with perfusion of cis-urocanic acid together with neuropeptide receptor antagonists in control rats. There was a small direct effect of cis-urocanic acid on microvascular blood flow. As both substance P and calcitonin gene-related peptide could directly degranulate connective tissue mast cells, this study suggests that cis-urocanic acid indirectly activates mast cells via its effects on peripheral terminals of unmyelinated primary afferent sensory nerves. cis-Urocanic-acid-induced neuropeptides may also contribute to ultraviolet-B-induced cutaneous inflammation and alterations to Langerhans cell activity.


Asunto(s)
Neuropéptidos/metabolismo , Nervios Periféricos/metabolismo , Sensación/fisiología , Ácido Urocánico/farmacología , Animales , Vesícula/fisiopatología , Degranulación de la Célula , Dermatitis por Contacto/fisiopatología , Femenino , Miembro Posterior , Masculino , Mastocitos/efectos de los fármacos , Mastocitos/fisiología , Ratones , Ratones Endogámicos BALB C , Microcirculación/efectos de los fármacos , Neuropéptidos/deficiencia , Cavidad Peritoneal/citología , Ratas , Ratas Sprague-Dawley , Piel/irrigación sanguínea , Estereoisomerismo , Rayos Ultravioleta
14.
J Invest Dermatol ; 115(2): 317-20, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10951253

RESUMEN

Ultraviolet B radiation (280-320 nm) can initiate skin cancer as well as suppress the immune system, thereby preventing the rejection of ultraviolet-B-induced tumors. Recently we reported that there was not only a correlation but also a functional link between dermal mast cell prevalence and susceptibility to ultraviolet-B-induced systemic immunosuppression in multiple strains of mice. In this study, we investigated whether increased dermal mast cell prevalence is a significant predisposing factor for basal cell carcinoma development in humans. In 21 Danes with a history of basal cell carcinoma and 20 control subjects of similar age, sex, skin phototype, and recreational sun exposure over the past 12 mo, dermal mast cell prevalence was quantified on non-sun-exposed buttock skin. We investigated this skin site in order to avoid any changes in mast cell prevalence caused by sun exposure and assumed that the prevalence of mast cells in buttock skin correlated with that at sun-exposed sites at critical times in the development of basal cell carcinomas. Patients with a history of basal cell carcinoma had a significantly higher median dermal mast cell prevalence than control subjects (p = 0.01, Mann-Whitney U ). No correlation was observed between dermal mast cell prevalence and age of basal cell carcinoma patients and control subjects. These results suggest that increased dermal mast cell prevalence is a predisposing factor for basal cell carcinoma development in humans. We hypothesize that mast cells function in humans, as in mice, by initiating immunosuppression and thereby allowing a permissive environment for basal cell carcinoma development.


Asunto(s)
Carcinoma Basocelular/patología , Mastocitos/patología , Lesiones Precancerosas/patología , Neoplasias Cutáneas/patología , Piel/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Humanos , Persona de Mediana Edad , Valores de Referencia
15.
J Invest Dermatol ; 114(3): 508-13, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10692110

RESUMEN

Ultraviolet B radiation is immunosuppressive by multiple mechanisms. In interleukin-4-/- mice, ultraviolet B radiation was not able to suppress delayed-type hypersensitivity or contact hypersensitivity responses when the sensitizing antigen was applied to nonirradiated sites. In contrast, ultraviolet B significantly suppressed contact hypersensitivity responses to haptens applied to irradiated sites in interleukin-4-/- mice. In mast cell depleted Wf/Wf mice, ultraviolet B radiation also significantly suppressed contact hypersensitivity responses to sensitizing antigens applied to irradiated but not to unirradiated sites. In both interleukin-4-/- mice and Wf/Wf mice, the mast cell product, histamine, was immunosuppressive implicating mast cells as the dysfunctional cell in interleukin-4-/- mice. The prevalence of dermal mast cells was similar in wild-type and interleukin-4-/- mice. Dermal mast cells of interleukin-4-/- mice, however, express very low levels of c-kit and did not significantly degranulate in response to ultraviolet B. Ultraviolet radiation induced significant and similar levels of serum interleukin-10 in wild-type and interleukin-4-/- mice. We conclude that interleukin-4 indirectly affects ultraviolet B suppression of contact hypersensitivity and delayed-type hypersensitivity responses to sensitizing antigens applied at sites other than those irradiated by providing a critical differentiative signal for dermal mast cells. This study further emphasizes the central role of mast cells in the initial processes by which ultraviolet B radiation is immunomodulatory for immune responses to sensitizing antigens applied to nonirradiated sites.


Asunto(s)
Formación de Anticuerpos/efectos de la radiación , Interleucina-4/análisis , Rayos Ultravioleta , Animales , Recuento de Células , Degranulación de la Célula , Dermatitis por Contacto/etiología , Hipersensibilidad Tardía/patología , Interleucina-10/sangre , Mastocitos/citología , Mastocitos/inmunología , Mastocitos/efectos de la radiación , Ratones , Ratones Endogámicos C57BL , Cloruro de Picrilo/inmunología , Piel/citología , Piel/efectos de la radiación , Bazo/citología
16.
Hypertension ; 22(1): 84-9, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8319996

RESUMEN

The prevalence of hypertension is greater for blacks than whites. Whether black children have higher blood pressure than white children is less clear. We investigated this issue through a prospective longitudinal assessment of blood pressure in 345 white children and 164 black children. Each child had his or her blood pressure measured every 6 months for 2 to 5.5 years. The means for systolic and diastolic blood pressures for each individual were calculated, and the rate of change in blood pressure over time for each subject was estimated. The mean blood pressure and the mean rate were compared between gender-specific black and white groups. For both boys and girls, the mean systolic blood pressure was 2 mm Hg higher in black children than white children (P = .0008). Boys had a higher systolic blood pressure than girls (P = .0048). The mean diastolic blood pressure was 1.5 mm Hg higher in black children than in white children (P = .0270); no significant gender difference in diastolic blood pressure was observed. Age, weight, height, and body mass index were highly correlated with blood pressure. When accounting for these variables, for girls the racial difference in systolic blood pressure remained significant, whereas the difference in diastolic blood pressure in boys and girls was no longer significant. The rate of increase in blood pressure over time was significantly greater in blacks than whites: for systolic blood pressure, P = .0002, and for diastolic blood pressure, P = .009.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Población Negra , Presión Sanguínea , Población Blanca , Envejecimiento/fisiología , Análisis de Varianza , Índice de Masa Corporal , Niño , Diástole , Femenino , Humanos , Estudios Longitudinales , Masculino , Estudios Prospectivos , Factores Sexuales , Sístole
17.
Hypertension ; 16(4): 462-7, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2145221

RESUMEN

We have previously shown that black children have higher blood pressures than white children. In the present study, we examined whether a possible racial difference in adrenal androgen production during adrenarche might contribute to the racial disparity in blood pressure. Adrenal androgen production was estimated from urinary excretion of adrenal androgen metabolites that showed cross-reactivity with antisera to dehydroepiandrosterone sulfate (DHEA-S). Urine samples were collected overnight in 798 children, one third of whom were black. Analyses were performed for two different age groups, less than 10 years and 10 years or more of age. In children less than 10 years of age, adrenal androgen excretion rates were 17% higher in blacks than in whites (p = 0.0099); adrenal androgen excretion rates tended to be higher in older black children as well, but differences here were not statistically significant. Adrenal androgen excretion rates were positively correlated with diastolic blood pressure in the older age group only (p = 0.014). However, when the relation of race to blood pressure was examined along with adrenal androgen excretion adjusted for age, sex, and weight, race remained an independent contributor to the level of blood pressure, suggesting that a difference in adrenal androgens could not explain the racial differences in blood pressure. In summary, black children produced more adrenal androgen, but this did not explain their higher blood pressures. In older children, where adrenal androgen excretion rates were higher, diastolic blood pressure and adrenal androgen excretion were positively related, suggesting that adrenal androgens participate in establishing the level of blood pressure in young people.


Asunto(s)
Glándulas Suprarrenales/fisiología , Andrógenos/orina , Presión Sanguínea , Factores de Edad , Andrógenos/fisiología , Población Negra , Niño , Deshidroepiandrosterona/análogos & derivados , Deshidroepiandrosterona/sangre , Sulfato de Deshidroepiandrosterona , Femenino , Humanos , Masculino , Población Blanca
18.
J Immunol Methods ; 100(1-2): 223-33, 1987 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-3298437

RESUMEN

Murine bone marrow cell cultures that had been established for up to 26 weeks were harvested each week and found to provide functional neutrophils. Leukocytes harvested from the cultures were enriched for neutrophils using discontinuous Percoll density gradients. These cells mounted a chemiluminescence response to Proteus mirabilis in the presence of normal mouse serum (NMS). They killed several NMS-opsonised bacterial species, an activity that was blocked by a monoclonal antibody to the C3 receptor of mouse neutrophils. Cultured bone marrow neutrophils expressed both Fc and C3 receptors. C3 receptor expression could be augmented by exposure to the chemotactic peptide f-Met-Leu-Phe. We conclude that murine bone marrow cell cultures provide a useful source of functional neutrophils, and that their productivity can be sustained in long-term culture. As their receptor expression can be augmented from the resting state by exogenous stimuli, they represent a useful cell source in studies of neutrophil activation.


Asunto(s)
Células de la Médula Ósea , Neutrófilos/inmunología , Animales , Fraccionamiento Celular , Células Cultivadas , Factores Estimulantes de Colonias/biosíntesis , Mediciones Luminiscentes , Antígeno de Macrófago-1 , Ratones , Ratones Endogámicos BALB C , N-Formilmetionina Leucil-Fenilalanina/farmacología , Receptores de Complemento/análisis , Receptores Fc/análisis
19.
Invest Ophthalmol Vis Sci ; 24(2): 253-7, 1983 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6298140

RESUMEN

Analysis of cell populations in the cornea may be performed rapidly and accurately employing the technique of enzymatic disaggregation. To illustrate this method normal rat corneas and corneas infected 24 and 48 hours previously with Staphylococcus aureus were disaggregated in a solution containing pancreatin and collagenase. The cells released were counted and identified morphologically. These results were compared to cell counts made from histologic sections. Over 95% of the corneal cells were viable after the disaggregation and leukocytes obtained from the infected corneas retained their phagocytic capacity. This approach allows sensitive analysis of cell populations in a wide range of corneal conditions, including infection and allograft rejection.


Asunto(s)
Córnea/patología , Queratitis/patología , Colagenasa Microbiana/farmacología , Pancreatina/farmacología , Animales , Agregación Celular/efectos de los fármacos , Recuento de Células , Queratitis/etiología , Leucocitos/fisiología , Masculino , Fagocitosis , Ratas , Infecciones Estafilocócicas
20.
Radiother Oncol ; 9(2): 137-45, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3303162

RESUMEN

From October 1962 through April 1982, 21 patients with the diagnosis of primary lymphoma of bone (18 monostotic, stages IE and IIE; 3 polyostotic) were treated with curative intent. A combination of chemotherapy and radiation therapy was used in 11 patients, local treatment alone in 9 patients, and chemotherapy alone in one patient. Overall 5-year survival for the patients treated with curative intent was 56%. Standard work-up has changed over the 20-year study period. Five-year survival for the subset of eight stage I and II patients with full pretherapy staging was 83%. Prognosis was significantly correlated with extent of pretherapy staging. Treatment parameters that also seemed to predict outcome were the aggressiveness of chemotherapy and the use of irradiation or surgery for local-regional disease; the only local failure occurred in the patient who received chemotherapy alone. Complications of radiation therapy alone and in combination with chemotherapy are discussed and correlated with irradiation dose. Radiation therapy techniques are described, and a management approach is recommended.


Asunto(s)
Neoplasias Óseas/terapia , Linfoma/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/radioterapia , Terapia Combinada , Femenino , Humanos , Linfoma/tratamiento farmacológico , Linfoma/radioterapia , Linfoma de Células B Grandes Difuso/diagnóstico por imagen , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma no Hodgkin/diagnóstico por imagen , Linfoma no Hodgkin/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Pronóstico , Radiografía
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