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1.
Eur Radiol ; 33(7): 4713-4722, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36735038

RESUMEN

OBJECTIVES: To examine the radiological patterns specifically associated with hypoxemic respiratory failure in patients with coronavirus disease (COVID-19). METHODS: We enrolled patients with COVID-19 confirmed by qPCR in this prospective observational cohort study. We explored the association of clinical, radiological, and microbiological data with the development of hypoxemic respiratory failure after COVID-19 onset. Semi-quantitative CT scores and dominant CT patterns were retrospectively determined for each patient. The microbiological evaluation included checking the SARS-CoV-2 viral load by qPCR using nasal swab and serum specimens. RESULTS: Of the 214 eligible patients, 75 developed hypoxemic respiratory failure and 139 did not. The CT score was significantly higher in patients who developed hypoxemic respiratory failure than in those did not (median [interquartile range]: 9 [6-14] vs 0 [0-3]; p < 0.001). The dominant CT patterns were subpleural ground-glass opacities (GGOs) extending beyond the segmental area (n = 44); defined as "extended GGOs." Multivariable analysis showed that hypoxemic respiratory failure was significantly associated with extended GGOs (odds ratio [OR] 29.6; 95% confidence interval [CI], 9.3-120; p < 0.001), and a CT score > 4 (OR 12.7; 95% CI, 5.3-33; p < 0.001). The incidence of RNAemia was significantly higher in patients with extended GGOs (58.3%) than in those without any pulmonary lesion (14.7%; p < 0.001). CONCLUSIONS: Extended GGOs along the subpleural area were strongly associated with hypoxemia and viremia in patients with COVID-19. KEY POINTS: • Extended ground-glass opacities (GGOs) along the subpleural area and a CT score > 4, in the early phase of COVID-19, were independently associated with the development of hypoxemic respiratory failure. • The absence of pulmonary lesions on CT in the early phase of COVID-19 was associated with a lower risk of developing hypoxemic respiratory failure. • Compared to patients with other CT findings, the extended GGOs and a higher CT score were also associated with a higher incidence of RNAemia.


Asunto(s)
COVID-19 , Insuficiencia Respiratoria , Humanos , SARS-CoV-2 , COVID-19/patología , Estudios Retrospectivos , Estudios Prospectivos , Tomografía Computarizada por Rayos X , Pulmón/patología , Insuficiencia Respiratoria/diagnóstico por imagen , Insuficiencia Respiratoria/patología
2.
J Infect Chemother ; 29(10): 993-996, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37331657

RESUMEN

Cladosporium cladosporioides is one of the most ubiquitous dematiaceous fungi that seldomly occur human infection. Here, we demonstrate a rare case of pulmonary phaeohyphomycosis with a distinctive pulmonary lesion during the nadir period of outpatient chemotherapy against endometrial cancer. In addition to severe neutropenia, excessive exposure to C. cladosporioides at patient's residence was considered as dominant causative factor. More caution is considered necessary for pulmonary phaeohyphomycosis in patients who receive outpatient chemotherapy and are homebound during neutropenic status.


Asunto(s)
Absceso Pulmonar , Feohifomicosis , Humanos , Feohifomicosis/tratamiento farmacológico , Pacientes Ambulatorios , Cladosporium
3.
Br J Dermatol ; 177(6): 1683-1692, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28703393

RESUMEN

BACKGROUND: Epidermolysis bullosa acquisita (EBA) is a rare, potentially devastating autoimmune disease of the skin. IgG autoantibodies directed against type VII collagen (Col7), the major component of anchoring fibrils, induce skin fragility leading to cutaneous and mucocutaneous blister formation, which is mostly of a scarring phenotype. Thus, powerful and reproducible diagnostic assays are critical to establish the diagnosis of EBA early to avoid irreversible sequelae. OBJECTIVES: The present international, retrospective multicentre study included a large cohort of patients with EBA and evaluated the diagnostic power of four different diagnostic assays for the detection of anti-Col7 IgG autoantibodies. METHODS: Overall, 95 EBA sera and 200 control sera consisting of 100 bullous pemphigoid sera, 50 pemphigus vulgaris sera and 50 sera of healthy controls were tested for anti-Col7 IgG autoantibodies using indirect immunofluorescence (IIF), two commercial enzyme-linked immunosorbent assay (ELISA) systems and Western blot (WB) analysis. EBA sera were taken from patients with positive direct immunofluorescence and IgG reactivity in at least one of the immunoserological assays (IIF, ELISA, WB). RESULTS: A Col7-NC1/NC2 ELISA (MBL, Nagoya, Japan) showed the highest sensitivity (97·9%), followed by a Col7-NC1 ELISA (Euroimmun, Lübeck, Germany) (89·5%), WB with Col7-NC1 (85·3%), and IIF on saline-split human skin (74·7%). The specificities of both ELISA systems were comparable (NC1 98·7%, NC1/NC2 99·3%). Furthermore, WB was more sensitive than IIF, which was more specific. CONCLUSIONS: The two commercially available ELISA systems allow for a highly sensitive and specific diagnosis of EBA. The sensitivity of the Col7-NC1/NC2 ELISA is significantly higher compared with the ELISA based on the Col7-NC1 domain only.


Asunto(s)
Autoanticuerpos/metabolismo , Colágeno Tipo VII/inmunología , Epidermólisis Ampollosa Adquirida/diagnóstico , Inmunoglobulina G/metabolismo , Vesícula/inmunología , Western Blotting , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoglobulina G/inmunología , Microscopía Fluorescente , Estudios Retrospectivos
4.
Br J Dermatol ; 169(6): 1314-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23909960

RESUMEN

BACKGROUND: Tuberous sclerosis complex (TSC) is an autosomal dominant disorder causing multiple hamartomas. Treatment of TSC lesions with mammalian target of rapamycin inhibitors is effective. Recently, several reports have shown the efficacy of topical rapamycin (sirolimus) for angiofibromas. However, almost all studies have been case studies and the 0·1% solution caused skin irritation. A comparative study of topical rapamycin and a vehicle has not yet been reported. OBJECTIVES: To compare the efficacy of topical rapamycin formulation with that of vehicle for angiofibromas. METHODS: A left-right comparative study between rapamycin 0·2% topical formulation and vehicle was conducted in 11 patients with TSC. Two formulations, an ointment and a gel, were prepared and in vitro percutaneous absorption of rapamycin was determined. RESULTS: In vitro percutaneous absorption of rapamycin was significantly greater with the gel compared with the ointment. In the clinical study, the rapamycin-treated cheek showed significant improvements relative to the vehicle-treated cheek in all outcome measures after 12 weeks of treatment. The improvement was particularly remarkable in children aged ≤ 10 years. No side-effects were noted, and rapamycin was not detected in the blood of the patients. CONCLUSIONS: Topical rapamycin was significantly effective against angiofibromas. Both formulations used were effective and safe. The 0·2% gel is especially useful because of its better skin penetration and low irritancy. Initiation of topical rapamycin therapy in early childhood would be beneficial for patients with TSC.


Asunto(s)
Angiofibroma/tratamiento farmacológico , Antibióticos Antineoplásicos/administración & dosificación , Neoplasias Faciales/tratamiento farmacológico , Sirolimus/administración & dosificación , Esclerosis Tuberosa/complicaciones , Administración Cutánea , Adolescente , Adulto , Angiofibroma/complicaciones , Niño , Preescolar , Neoplasias Faciales/complicaciones , Femenino , Geles/administración & dosificación , Humanos , Masculino , Recurrencia Local de Neoplasia/etiología , Pomadas/administración & dosificación , Resultado del Tratamiento
6.
Front Immunol ; 14: 1197436, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37731495

RESUMEN

Background: Immune response indicators in the early phase of COVID-19, including interferon and neutralizing responses against SARS-CoV-2, which predict hypoxemia remains unclear. Methods: This prospective observational study recruited patients hospitalized with COVID-19 (before emergence of omicron variant). As the immune indicators, we assessed the serum levels of IFN-I/III, IL-6, CXCL10 and VEGF, using an ELISA at within 5 days after the onset of symptoms, and serum neutralizing responses using a pseudovirus assay. We also assessed SARS-CoV-2 viral load by qPCR using nasal-swab specimens and serum, to assess the association of indicators and viral distribution. Results: The study enrolled 117 patients with COVID-19, of which 28 patients developed hypoxemia. None received vaccine before admission. Serum IFN-I levels (IFN-α and IFN-ß), IL-6, CXCL10, LDH and CRP were significantly higher in patients who developed hypoxemia. A significant association with nasopharyngeal viral load was observed only for IFN-I. The serum levels of IFN-α, IL-6, CXCL10 were significantly associated with the presence of RNAemia. Multivariable analysis showed higher odds ratio of IFN-α, with cut-off value of 107 pg/ml, in regard to hypoxemia (Odds ratio [OR]=17.5; 95% confidence interval [CI], 4.7-85; p<0.001), compared to those of IL-6, >17.9 pg/ml (OR=10.5; 95% CI, 2.9-46; p<0.001). Conclusions: This study demonstrated that serum IFN-α levels in the early phase of SARS-CoV-2 infection strongly predict hypoxemic respiratory failure in a manner different from that of the other indicators including IL-6 or humoral immune response, and instead sensitively reflect innate immune response against SARS-CoV-2 invasion.


Asunto(s)
COVID-19 , Interferón Tipo I , Insuficiencia Respiratoria , Humanos , SARS-CoV-2 , Interleucina-6 , Interferón-alfa , Hipoxia
7.
J Exp Bot ; 62(6): 2063-77, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21239383

RESUMEN

The primary inflorescence stem of Arabidopsis thaliana is rich in lignified cell walls, in both vascular bundles and interfascicular fibres. Previous gene expression studies demonstrated a correlation between expression of phenylpropanoid biosynthetic genes and a subset of genes encoding ATP-binding cassette (ABC) transporters, especially in the ABCB/multi-drug resistance/P-glycoprotein (ABCB/MDR/PGP) and ABCG/pleiotropic drug resistance (ABCG/PDR) subfamilies. The objective of this study was to characterize these ABC transporters in terms of their gene expression and their function in development of lignified cells. Based on in silico analyses, four ABC transporters were selected for detailed investigation: ABCB11/MDR8, ABCB14/MDR12, ABCB15/MDR13, and ABCG33/PDR5. Promoter::glucuronidase reporter assays for each gene indicated that promoters of ABCB11, ABCB14, ABCB15, and ABCG33 transporters are active in the vascular tissues of primary stem, and in some cases in interfascicular tissues as well. Homozygous T-DNA insertion mutant lines showed no apparent irregular xylem phenotype or alterations in interfascicular fibre lignification or morphology in comparison with wild type. However, in abcb14-1 mutants, stem vascular morphology was slightly disorganized, with decreased phloem area in the vascular bundle and decreased xylem vessel lumen diameter. In addition, abcb14-1 mutants showed both decreased polar auxin transport through whole stems and altered auxin distribution in the procambium. It is proposed that both ABCB14 and ABCB15 promote auxin transport since inflorescence stems in both mutants showed a reduction in polar auxin transport, which was not observed for any of the ABCG subfamily mutants tested. In the case of ABCB14, the reduction in auxin transport is correlated with a mild disruption of vascular development in the inflorescence stem.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Lignina/metabolismo , Tallos de la Planta/metabolismo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/metabolismo , Glucuronidasa , Familia de Multigenes , Tallos de la Planta/crecimiento & desarrollo , Haz Vascular de Plantas/metabolismo , Regiones Promotoras Genéticas
8.
Br J Dermatol ; 165(4): 912-6, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21692771

RESUMEN

BACKGROUND: Dysregulation of mTOR signalling by mutations in tuberin and/or hamartin leads to the formation of tuberous sclerosis complex (TSC). Trials to treat TSC using mTOR inhibitors, including rapamycin, have been performed. Although rapamycin improves many TSC lesions, significant side-effects appear after systemic administration. Topical administration has been recommended. OBJECTIVES: The efficacy of rapamycin-tacrolimus ointment was examined for TSC-related angiofibroma. METHODS: Left-right comparisons of the tacrolimus ointments with/without 0·2% rapamycin was conducted in symmetrical facial angiofibromas in nine patients with definitive TSC. After the 3-month treatment, a cumulative score for redness, flatness and papule size was used to evaluate the efficacy of the treatment. Blood rapamycin levels were analysed by liquid chromatography-electrospray mass spectrometry (LC-ESI/MS). RESULTS: At the end of the treatment, all of the scores significantly improved for rapamycin-tacrolimus treatment compared with tacrolimus alone. No adverse reactions were noted and blood levels of rapamycin were below the detection limit in all cases. CONCLUSIONS: Topical application of rapamycin-tacrolimus ointment is a safe and useful treatment for TSC-related angiofibroma.


Asunto(s)
Angiofibroma/tratamiento farmacológico , Neoplasias Faciales/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Sirolimus/administración & dosificación , Tacrolimus/administración & dosificación , Esclerosis Tuberosa/complicaciones , Administración Cutánea , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Angiofibroma/etiología , Niño , Combinación de Medicamentos , Neoplasias Faciales/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pomadas , Vehículos Farmacéuticos/administración & dosificación , Proyectos Piloto , Resultado del Tratamiento , Adulto Joven
9.
Br J Dermatol ; 163(4): 704-10, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20518783

RESUMEN

BACKGROUND: Vascular-type Ehlers-Danlos syndrome (vEDS) is a severe autosomal dominant inherited disorder resulting from mutations within the α1 type III collagen gene (COL3A1). The majority of published mutations are base changes leading to the substitution of single glycine residues within the triple-helical domain of type III collagen. Although clinical characteristics and mutations in the COL3A1 gene have been analysed for some patients from Europe and America, similar analyses have not yet been performed for Japanese patients with vEDS. OBJECTIVES: To analyse the genetic and phenotypic findings in Japanese patients with vEDS. METHODS: We analysed the clinical features of 20 unrelated individuals with vEDS. To quantify type III collagen production, the fibroblasts were cultured with (3) H-proline, and the radiolabelled collagenous proteins were analysed using sodium dodecyl sulphate-polyacrylamide gel electrophoresis and fluorography. Mutations in COL3A1 were detected by sequence analysis of cDNA from patients' fibroblasts and subsequently by a genomic DNA sequence analysis. RESULTS: Thin and translucent skin with extensive bruising and hypermobility of the small joints were observed in about 90% of the patients, whereas the prevalence of serious clinical findings such as rupture/dissection/aneurysm of the arteries (30%) or rupture of the gastrointestinal tract (25%) was relatively low. Sequence analyses of the COL3A1 gene demonstrated heterozygous point mutations leading to glycine substitution in only nine patients (45%), while heterozygous splice-site mutations at the junction of the triple-helical exons were observed in the remaining 11 patients (55%). The average type III collagen production level in the cultured dermal fibroblasts was 14·6% of the normal value. The types of complication were not associated with specific mutations in COL3A1. CONCLUSION: The analysis in the present series revealed a low frequency of patients presenting with serious clinical findings such as arterial rupture/arterial dissection/aneurysm and perforation or rupture of the gastrointestinal tract, and revealed a higher prevalence of splice-site mutations at the junction of the triple-helical exons than of glycine substitution mutations in COL3A1.


Asunto(s)
Síndrome de Ehlers-Danlos/genética , Enfermedades Cutáneas Vasculares/genética , Adolescente , Adulto , Células Cultivadas , Colágeno Tipo III/biosíntesis , Colágeno Tipo III/genética , Análisis Mutacional de ADN/métodos , Síndrome de Ehlers-Danlos/diagnóstico , Síndrome de Ehlers-Danlos/metabolismo , Femenino , Fibroblastos/metabolismo , Humanos , Masculino , Mutación Puntual , Piel/metabolismo , Enfermedades Cutáneas Vasculares/diagnóstico , Enfermedades Cutáneas Vasculares/metabolismo , Adulto Joven
10.
J Chem Phys ; 132(14): 144502, 2010 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-20405996

RESUMEN

Secondary ion mass spectra have been measured for the first time for a liquid ethanol target bombarded by 2.0 MeV He(+) ions. Positive and negative ion spectra exhibit evidently a series of cluster ions of the forms [(EtOH)(n)H](+) and [(EtOH)(n)-H](-), respectively, in addition to light fragment ions from intact parent molecules. It was found that these cluster ions are produced only from liquid phase ethanol. Both positive and negative secondary ion spectra show similar cluster size distributions with almost the same decay slope. We also present for the first time the cluster ion distribution emitted from the liquid at different liquid temperatures.


Asunto(s)
Etanol/química , Iones/química , Espectrometría de Masa de Ion Secundario
12.
J Cell Biol ; 104(1): 1-7, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3539946

RESUMEN

A monoclonal antibody that recognizes antigenic determinants on the nucleus of cultured mammalian cells was isolated. Immunofluorescence studies using this antibody showed that the recognized antigen was present not only on the nucleus but also in cytoplasmic vesicles of interphase cells and in the perichromosomal region of mitotic cells. Premature chromosome condensation analysis showed that the reactive site for this monoclonal antibody could be detected in the perichromosomal region during the G2 and M phases, but not during the G1 and S phases. Finally, immunoblot analysis showed that this monoclonal antibody prepared against the nucleus recognized a protein of approximately 40 kD both in the cytoplasm and in the perichromosomal regions.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Núcleo Celular/inmunología , Gránulos Citoplasmáticos/inmunología , Animales , Especificidad de Anticuerpos , Núcleo Celular/ultraestructura , Cromosomas/inmunología , Técnica del Anticuerpo Fluorescente , Humanos , Inmunoglobulina M/inmunología , Técnicas de Inmunoadsorción , Interfase , Membranas Intracelulares/inmunología , Mitosis , Peso Molecular , Membrana Nuclear/inmunología , Proteínas/inmunología
13.
Kyobu Geka ; 62(11): 1019-21, 2009 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-19827559

RESUMEN

The patient was 64-year-old male. Chest computed tomography (CT) scan revealed an 18 mm of nodular lesion in the right upper lobe, in which inflammatory lesions due to the Mycobacterium avium infection was preexisted. On fluorodeoxyglucose-positron emission tomography (FDG-PET)/CT scan, value of standard uptake value (SUV) max was 4.0. This finding may be caused by the inflammatory change but the malignancy was more likely with a concomitant finding of elevated serum carcinoembryonic antigen (CEA). Surgical resection by right upper lobectomy was performed. Postoperative pathology confirmed the existence of adenocarcinoma in the lesions of epithelioid granuloma with giant cells. FDG-PET/CT contributed effectively to detect a malignancy in the inflammatory lesions of Mycobacterium avium infection.


Asunto(s)
Adenocarcinoma/diagnóstico , Neoplasias Pulmonares/diagnóstico , Infección por Mycobacterium avium-intracellulare/complicaciones , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Fluorodesoxiglucosa F18 , Humanos , Masculino , Persona de Mediana Edad , Radiofármacos
15.
Neurosci Res ; 137: 23-29, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29522783

RESUMEN

Signaling by glutamatergic synapses plays an important role in visual processing in the retina. In this study, we used an enzyme-linked fluorescence assay system to monitor the dynamics of extracellular glutamate in a slice preparation from the mouse retina. High K stimulation induced an elevation of fluorescence in the inner plexiform layer (IPL) of the retina when glutamate transporters were inhibited by dl-threo-ß-benzyloxyaspartic acid (TBOA). The high K-induced fluorescence signals in the IPL were inhibited by the calcium channel blocker Cd2+. Blockade of GABAergic and glycinergic circuits by picrotoxin and strychnine also elevated the fluorescence signals in the IPL. Thus, the enzyme-linked fluorescence assay system might be useful for monitoring the bulk concentration of extracellular glutamate released by synapses in the inner retina.


Asunto(s)
Ácido Glutámico/metabolismo , Retina/metabolismo , Animales , Ácido Aspártico/análogos & derivados , Ácido Aspártico/farmacología , Compuestos de Cadmio/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Ensayo de Inmunoadsorción Enzimática , Antagonistas del GABA/farmacología , Ratones , Ratones Endogámicos C57BL , Picrotoxina/farmacología , Potasio/farmacología , Células Ganglionares de la Retina/efectos de los fármacos , Células Ganglionares de la Retina/metabolismo , Espectrometría de Fluorescencia , Estricnina/farmacología , Sinapsis/metabolismo , Proteínas de Transporte Vesicular de Glutamato/metabolismo
16.
Bone Marrow Transplant ; 40(4): 335-8, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17572709

RESUMEN

Hematopoietic SCT has improved the survival rates of patients with hematologic and metabolic disorders, as well as those with malignancy or immunodeficiency. Although various complications have been reported following allogeneic SCT, phimosis has rarely been reported, and the predisposing risk factors for phimosis have not been determined. In this study, the occurrence of severe phimosis following allogeneic SCT in boys was analyzed, and its risk factors were determined. The patients were under 15 years of age. Phimosis was observed in 32.6% of 46 patients after allogeneic SCT; 13.0% of cases required surgery. On univariate analysis, risk factors for severe phimosis included chronic GVHD and the use of a conditioning regimen including anti-thymocyte globulin (ATG). Multivariate analysis showed that chronic GVHD was an independent risk factor for severe phimosis. Thus, severe phimosis is an important complication of SCT in boys, especially in patients with chronic GVHD.


Asunto(s)
Enfermedad Injerto contra Huésped/complicaciones , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Fimosis/etiología , Adolescente , Suero Antilinfocítico/efectos adversos , Niño , Preescolar , Humanos , Lactante , Japón , Masculino , Estudios Retrospectivos , Factores de Riesgo , Trasplante Homólogo
17.
Mol Cell Biol ; 21(11): 3775-88, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11340170

RESUMEN

Mutations in the spin gene are characterized by an extraordinarily strong rejection behavior of female flies in response to male courtship. They are also accompanied by decreases in the viability, adult life span, and oviposition rate of the flies. In spin mutants, some oocytes and adult neural cells undergo degeneration, which is preceded by reductions in programmed cell death of nurse cells in ovaries and of neurons in the pupal nervous system, respectively. The central nervous system (CNS) of spin mutant flies accumulates autofluorescent lipopigments with characteristics similar to those of lipofuscin. The spin locus generates at least five different transcripts, with only two of these being able to rescue the spin behavioral phenotype; each encodes a protein with multiple membrane-spanning domains that are expressed in both the surface glial cells in the CNS and the follicle cells in the ovaries. Orthologs of the spin gene have also been identified in a number of species from nematodes to humans. Analysis of the spin mutant will give us new insights into neurodegenerative diseases and aging.


Asunto(s)
Apoptosis , Sistema Nervioso Central/patología , Proteínas de Drosophila , Drosophila melanogaster/fisiología , Proteínas de Insectos/fisiología , Proteínas de la Membrana/fisiología , Secuencia de Aminoácidos , Animales , Animales Modificados Genéticamente , Secuencia de Bases , Conducta Animal , Sistema Nervioso Central/metabolismo , ADN Complementario , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Femenino , Humanos , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Lipofuscina/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Mutagénesis , Degeneración Nerviosa , Neuroglía/metabolismo , Folículo Ovárico/metabolismo , Ovario/crecimiento & desarrollo , Fenotipo
18.
Cytogenet Genome Res ; 113(1-4): 6-11, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16575156

RESUMEN

The discovery of the phenomenon of genomic imprinting in mammals showed that the parental genomes are functionally non-equivalent. Considerable advances have occurred in the field over the past 20 years, which has resulted in the identification and functional analysis of a number of imprinted genes the expression of which is determined by their parental origin. These genes belong to many diverse categories and they have been shown to regulate growth, complex aspects of mammalian physiology and behavior. Many aspects of the mechanism of imprinting have also been elucidated. However, the reasons for the evolution of genomic imprinting remain enigmatic. Further research is needed to determine if there is any relationship between the apparently diverse functions of imprinted genes in mammals, and their role in human diseases. It also remains to be seen what common features exist amongst the diverse imprinting control elements. The mechanisms involved in the erasure and re-establishment of imprints should provide deeper insights into epigenetic mechanisms of wide general interest.


Asunto(s)
Impresión Genómica , Mamíferos/genética , Animales , Desarrollo Embrionario , Femenino , Masculino , Mamíferos/metabolismo , Mamíferos/psicología , Reproducción
19.
Biochim Biophys Acta ; 882(1): 63-70, 1986 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-3011110

RESUMEN

Exposure to hypertonic glycerol induced cyanide-insensitive oxygen consumption and formation of superoxide anion (O-2) in leukocytes such as porcine blood polymorphonuclear leukocytes, guinea pig peritoneal leukocytes and guinea pig alveolar macrophages. Generation of O-2 occurred after a short lag time, remained maximal for a certain time and then stopped. Its termination was not due to cell damage, since cells exposed to glycerol did not release cytosolic enzymes such as lactate dehydrogenase and exhibited a subsequent respiratory burst upon addition of other stimulators such as myristic acid and phorbol myristate acetate. The period of O-2 generation increased linearly as a function of the glycerol concentration; cells exposed to 20% (v/v) glycerol produced O-2 for 10 min. The maximal velocity of O-2 generation also increased with the concentration of glycerol, reaching a plateau at 10% glycerol. Membrane vesicles isolated from the cells exposed to 20% glycerol showed high activity of NADPH-dependent O-2 generation as compared to those of unexposed cells. Activation of leukocytes by glycerol was not accompanied by degranulation, unlike stimulation by phagocytosis. A marked change in shape of the cell membrane of glycerol-treated cells was observed by light and scanning electron microscopies.


Asunto(s)
Glicerol/farmacología , Leucocitos/efectos de los fármacos , Proteínas de la Membrana/metabolismo , NADH NADPH Oxidorreductasas/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Animales , Activación Enzimática/efectos de los fármacos , Cobayas , Soluciones Hipertónicas/farmacología , Leucocitos/metabolismo , Leucocitos/ultraestructura , Microscopía Electrónica de Rastreo , NADPH Oxidasas , Oxidación-Reducción , Superóxidos/biosíntesis , Porcinos
20.
Biochim Biophys Acta ; 933(3): 450-9, 1988 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-2833923

RESUMEN

The assignment of cytochrome b-558 as a component of the O2- (H2O2) -generating enzyme in guinea-pig alveolar macrophages was investigated. Guinea pig alveolar macrophages contained 76 pmol cytochrome b-558/mg protein, a value very similar to that of neutrophils. The rate of myristic acid-stimulated O2- generation by alveolar macrophages, calculated per cytochrome b-558, was only one-fourth that of neutrophils. An analysis of Percoll density gradient centrifugation profiles showed that the H2O2-generating activity of myristic acid-activated alveolar macrophages was concentrated in a single peak which was consistently associated with 5'-nucleotidase activity, a plasma membrane marker enzyme. A little H2O2-generating activity was seen with unactivated alveolar macrophages. Furthermore, the cytochrome b-558 of both myristic acid-activated and unactivated alveolar macrophages was also predominantly associated with 5'-nucleotidase activity and was found in trace amounts in a peak containing lysozyme activity, a marker of lysosome granules. Only about 6% of the cytochrome b-558 in plasma membranes from myristic acid-activated guinea-pig alveolar macrophages was anaerobically reduced by 0.5 mM NADPH, while under the same conditions about 30% of the heme protein of myristic acid-activated neutrophils was reduced. These results suggest two conclusions: firstly, that in both activated and unactivated alveolar macrophages, cytochrome b-558 is located in the plasma membrane, and the translocation of cytochrome b-558 does not occur during the activation of NADPH oxidase; and secondly, that a smaller part of cytochrome b-558 is associated with the activated NADPH oxidase of guinea pig alveolar macrophages compared with neutrophils.


Asunto(s)
Grupo Citocromo b/análisis , Macrófagos/análisis , NADH NADPH Oxidorreductasas/análisis , Alveolos Pulmonares/citología , Animales , Fraccionamiento Celular , Membrana Celular/análisis , Membrana Celular/metabolismo , Grupo Citocromo b/metabolismo , Cobayas , Peróxido de Hidrógeno/metabolismo , Activación de Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/ultraestructura , Masculino , Ácido Mirístico , Ácidos Mirísticos/farmacología , NADH NADPH Oxidorreductasas/metabolismo , NADP/farmacología , NADPH Oxidasas , Alveolos Pulmonares/metabolismo , Espectrofotometría , Superóxidos/metabolismo
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