Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 794
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Nature ; 593(7860): 548-552, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33882562

RESUMEN

Global peatlands store more carbon than is naturally present in the atmosphere1,2. However, many peatlands are under pressure from drainage-based agriculture, plantation development and fire, with the equivalent of around 3 per cent of all anthropogenic greenhouse gases emitted from drained peatland3-5. Efforts to curb such emissions are intensifying through the conservation of undrained peatlands and re-wetting of drained systems6. Here we report eddy covariance data for carbon dioxide from 16 locations and static chamber measurements for methane from 41 locations in the UK and Ireland. We combine these with published data from sites across all major peatland biomes. We find that the mean annual effective water table depth (WTDe; that is, the average depth of the aerated peat layer) overrides all other ecosystem- and management-related controls on greenhouse gas fluxes. We estimate that every 10 centimetres of reduction in WTDe could reduce the net warming impact of CO2 and CH4 emissions (100-year global warming potentials) by the equivalent of at least 3 tonnes of CO2 per hectare per year, until WTDe is less than 30 centimetres. Raising water levels further would continue to have a net cooling effect until WTDe is within 10 centimetres of the surface. Our results suggest that greenhouse gas emissions from peatlands drained for agriculture could be greatly reduced without necessarily halting their productive use. Halving WTDe in all drained agricultural peatlands, for example, could reduce emissions by the equivalent of over 1 per cent of global anthropogenic emissions.

2.
Clin Exp Dermatol ; 47(1): 24-29, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34459019

RESUMEN

The term 'pemphigus' refers to chronic autoimmune skin disorders that cause blistering erosions on the skin and oral mucosa. The two major clinical forms are pemphigus vulgaris and pemphigus foliaceus. Although rare, they confer a stark symptomatic burden upon patients that significantly impacts daily life. Comorbid mental health issues are not routinely screened for in patients with pemphigus, and current UK guidance provides no formal provision for the identification and treatment of psychological issues. This review is the first of its kind, to our knowledge, to systematically examine the available evidence on mental health issues in pemphigus. Published work suggests that the incidence of anxiety and depression is much higher in patients with pemphigus compared with both the general population and with patients having other chronic skin disorders. Disease severity appears to be closely linked to mental health, with worsening of pemphigus associated with deteriorations in psychological wellbeing. Corticosteroids, which are associated with depression in chronic use, are the current first-line therapy for pemphigus and have been identified as a potential confounder and independent risk factor for mental health comorbidity in pemphigus. Current evidence is unclear whether a bidirectional relationship exists between mental health and pemphigus severity, and more thorough research is required to develop understanding of this issue. In conclusion, we have identified a high incidence of mental health comorbidity in pemphigus, and recommend routine screening of patients with pemphigus for mental health issues and signposting toward mental health services as an initial measure to address this.


Asunto(s)
Trastornos Mentales/etiología , Pénfigo/complicaciones , Pénfigo/psicología , Humanos
3.
Age Ageing ; 48(2): 178-184, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30395169

RESUMEN

Age and Ageing is now inviting papers on healthcare improvement for older people. In this article we outline the nature and scope of healthcare improvement and reference improvement models and the tools and methods of improvement science. We emphasise the issues of sustainability, including scale and spread; evaluation - including associated ethical consideration and the involvement of patients and the public in healthcare improvement and associated research. Throughout we refer to resources the authors have found useful in their own work, and provide a bibliography of sources and web-links which will provide essential guidance and support for potential contributors to this new category of submission to Age and Ageing.


Asunto(s)
Servicios de Salud para Ancianos , Mejoramiento de la Calidad , Anciano , Investigación sobre Servicios de Salud , Humanos , Publicaciones Periódicas como Asunto
4.
Risk Anal ; 39(2): 375-388, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29958320

RESUMEN

An omnibus spending bill in 2014 directed the Department of Energy to analyze how effectively Department of Energy (DOE) identifies, programs, and executes its plans to address public health and safety risks that remain as part of DOE's remaining environmental cleanup liabilities. A committee identified two dozen issues and associated recommendations for the DOE, other federal agencies, and the U.S. Congress to consider, as well as other stakeholders such as states and tribal nations. In regard to risk assessment, the committee described a risk review process that uses available data, expert experience, identifies major data gaps, permits input from key stakeholders, and creates an ordered set of risks based on what is known. Probabilistic risk assessments could be a follow-up from these risk reviews. In regard to risk management, the states, in particular, have become major drivers of how resources are driven. States use different laws, different priorities, and challenge DOE's policies in different ways. Land use decisions vary, technology choices are different, and other notable variations are apparent. The cost differences associated with these differences are marked. The net result is that resources do not necessarily go to the most prominent human health and safety risks, as seen from the national level.

5.
Hum Reprod ; 32(3): 531-543, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28130434

RESUMEN

STUDY QUESTION: What is the impact of administration of the selective progesterone receptor modulator (SPRM), ulipristal acetate (UPA) on the endometrium of women with fibroids? SUMMARY ANSWER: UPA administration altered expression of sex-steroid receptors and progesterone-regulated genes and was associated with low levels of glandular and stromal cell proliferation. WHAT IS KNOWN ALREADY: Administration of all SPRM class members results in PAEC (progesterone receptor modulator associated endometrial changes). Data on the impact of the SPRM UPA administration on endometrial sex-steroid receptor expression, progesterone (P)-regulated genes and cell proliferation are currently lacking. STUDY DESIGN SIZE, DURATION: Observational study with histological and molecular analyses to delineate impact of treatment with UPA on endometrium. Endometrial samples (n = 9) were collected at hysterectomy from women aged 39 to 49 with uterine fibroids treated with UPA (oral 5 mg daily) for 9-12 weeks. Control proliferative (n = 9) and secretory (n = 9) endometrium from women aged 38-52 with fibroids were derived from institutional tissue archives. PARTICIPANTS/MATERIALS, SETTING, METHODS: Study setting was a University Research Institute. Endometrial biopsies were collected with institutional ethical approval and written informed consent. Concentrations of mRNAs encoded by steroid receptors, P-regulated genes and factors in decidualised endometrium were quantified with qRT-PCR. Immunohistochemistry was employed for localization of progesterone (PR, PRB), androgen (AR), estrogen (ERα) receptors and expression of FOXO1, HAND2, HOXA10, PTEN homologue. Endometrial glandular and stromal cell proliferation was objectively quantified using Ki67. MAIN RESULTS AND THE ROLE OF CHANCE: UPA induced morphological changes in endometrial tissue consistent with PAEC. A striking change in expression patterns of PR and AR was detected compared with either proliferative or secretory phase samples. There were significant changes in pattern of expression of mRNAs encoded by IGFBP-1, FOXO1, IL-15, HAND2, IHH and HOXA10 compared with secretory phase samples consistent with low agonist activity in endometrium. Expression of mRNA encoded by FOXM1, a transcription factor implicated in cell cycle progression, was low in UPA-treated samples. Cell proliferation (Ki67 positive nuclei) was lower in samples from women treated with UPA compared with those in the proliferative phase. LARGE SCALE DATA: N/A. LIMITATIONS REASONS FOR CAUTION: A small number of well-characterized patients were studied in-depth. The impacts on morphology, molecular and cellular changes with SPRM, UPA administration on symptom control remains to be determined. WIDER IMPLICATIONS OF THE FINDINGS: P plays a pivotal role in endometrial function. P-action is mediated through interaction with the PR. These data provide support for onward development of the SPRM class of compounds as effective long-term medical therapy for heavy menstrual bleeding. STUDY FUNDING/COMPETING INTEREST(S): H.O.D.C. received has clinical research support for laboratory consumables and staff from Bayer Pharma Ag and provides consultancy advice (no personal remuneration) for Bayer Pharma Ag, PregLem SA, Gedeon Richter, Vifor Pharma UK Ltd, AbbVie Inc.; A.R.W.W. has received consultancy payments from Bayer, Gedeon Richter, Preglem SA, HRA Pharma; L.H.R.W., A.A.M., R.M., G.S. and P.T.K.S. have no conflicts of interest. Study funded in part from each of: Medical Research Council (G1002033; G1100356/1; MR/N022556/1); National Health Institute for Health Research (12/206/520) and TENOVUS Scotland.


Asunto(s)
Anticonceptivos Femeninos/farmacología , Endometrio/efectos de los fármacos , Leiomioma/metabolismo , Norpregnadienos/farmacología , Receptores de Progesterona/metabolismo , Células del Estroma/efectos de los fármacos , Adulto , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Proliferación Celular/efectos de los fármacos , Femenino , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Proteínas Homeobox A10 , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Interleucina-15/genética , Interleucina-15/metabolismo , Persona de Mediana Edad , Receptores de Progesterona/genética , Células del Estroma/metabolismo
6.
Immunol Cell Biol ; 94(8): 802-8, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27430370

RESUMEN

Adoptive transfer of tumor-specific cytotoxic T cells is a promising advance in cancer therapy. Similarly, checkpoint inhibition has shown striking clinical results in some patients. Here we combine adoptive cell transfer with ablation of the checkpoint protein Src homology 2-domain-containing phosphatase 1 (SHP-1, Ptpn6). Naturally occurring motheaten mice lack SHP-1 and do not survive weaning due to extensive immunopathology. To circumvent this limitation, we created a novel SHP-1(null) mouse that is viable up to 12 weeks of age by knocking out IL1r1. Using this model, we demonstrate that the absence of SHP-1 augments the ability of adoptively transferred CD8(+) T cells to control tumor growth. This therapeutic effect was only observed in situations where T-cell numbers were limited, analogous to clinical settings. However, adoptive transfer of non-CD8(+) SHP-1(null) hematopoietic cells resulted in lethal motheaten-like pathology, indicating that systemic inhibition of SHP-1 could have serious adverse effects. Despite this caveat, our findings support the development of SHP-1 inhibition strategies in human T cells to complement adoptive transfer therapies in the clinic.


Asunto(s)
Traslado Adoptivo , Linfocitos T CD8-positivos/inmunología , Inmunoterapia Adoptiva , Melanoma Experimental/inmunología , Melanoma Experimental/terapia , Proteína Tirosina Fosfatasa no Receptora Tipo 6/deficiencia , Animales , Línea Celular Tumoral , Citometría de Flujo , Ratones Endogámicos C57BL , Metástasis de la Neoplasia , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Receptores Tipo I de Interleucina-1/deficiencia , Receptores Tipo I de Interleucina-1/metabolismo
8.
Neural Plast ; 2016: 2828536, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26819763

RESUMEN

The perineuronal net (PN) is a subtype of extracellular matrix appearing as a net-like structure around distinct neurons throughout the whole CNS. PNs surround the soma, proximal dendrites, and the axonal initial segment embedding synaptic terminals on the neuronal surface. Different functions of the PNs are suggested which include support of synaptic stabilization, inhibition of axonal sprouting, and control of neuronal plasticity. A number of studies provide evidence that removing PNs or PN-components results in renewed neurite growth and synaptogenesis. In a mouse model for Purkinje cell degeneration, we examined the effect of deafferentation on synaptic remodeling and modulation of PNs in the deep cerebellar nuclei. We found reduced GABAergic, enhanced glutamatergic innervations at PN-associated neurons, and altered expression of the PN-components brevican and hapln4. These data refer to a direct interaction between ECM and synapses. The altered brevican expression induced by activated astrocytes could be required for an adequate regeneration by promoting neurite growth and synaptogenesis.


Asunto(s)
Núcleos Cerebelosos/fisiopatología , Degeneración Nerviosa/fisiopatología , Red Nerviosa/fisiopatología , Plasticidad Neuronal/fisiología , Células de Purkinje/patología , Sinapsis/fisiología , Animales , Núcleos Cerebelosos/patología , Modelos Animales de Enfermedad , Ratones , Degeneración Nerviosa/patología , Red Nerviosa/patología , Sinapsis/patología
9.
Cereb Cortex ; 23(2): 349-60, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22368089

RESUMEN

The Cat-301 monoclonal antibody identifies aggrecan, a chondroitin sulfate proteoglycan in the cat visual cortex and dorsal lateral geniculate nucleus (dLGN). During development, aggrecan expression increases in the dLGN with a time course that matches the decline in plasticity. Moreover, examination of tissue from selectively visually deprived cats shows that expression is activity dependent, suggesting a role for aggrecan in the termination of the sensitive period. Here, we demonstrate for the first time that the onset of aggrecan expression in area 17 also correlates with the decline in experience-dependent plasticity in visual cortex and that this expression is experience dependent. Dark rearing until 15 weeks of age dramatically reduced the density of aggrecan-positive neurons in the extragranular layers, but not in layer IV. This effect was reversible as dark-reared animals that were subsequently exposed to light showed normal numbers of Cat-301-positive cells. The reduction in aggrecan following certain early deprivation regimens is the first biochemical correlate of the functional changes to the γ-aminobutyric acidergic system that have been reported following early deprivation in cats.


Asunto(s)
Agrecanos/metabolismo , Plasticidad Neuronal/fisiología , Corteza Visual/crecimiento & desarrollo , Corteza Visual/metabolismo , Animales , Gatos , Inmunohistoquímica , Luz , Privación Sensorial/fisiología
10.
Nat Genet ; 7(2): 195-200, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7920641

RESUMEN

Methylenetetrahydrofolate reductase (MTHFR) catalyses the reduction of methylenetetrahydrofolate to methyltetrahydrofolate, a cofactor for homocysteine methylation to methionine. MTHFR deficiency, an autosomal recessive disorder, results in homocysteinemia. Using degenerate oligonucleotides based on porcine peptide sequence data, we isolated a 90-bp cDNA by PCR from pig liver RNA. This cDNA was used to isolate a human cDNA, the predicted amino acid sequence of which shows strong homology to porcine MTHFR and to bacterial metF genes. The human gene has been localized to chromosome 1p36.3. Two mutations were identified in MTHFR-deficient patients: a missense mutation (Arg to Gln), in a residue conserved in bacterial enzymes, and a nonsense mutation (Arg to Ter).


Asunto(s)
ADN Complementario/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Mutación Puntual , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/genética , Secuencia de Bases , Enfermedades Cardiovasculares/enzimología , Enfermedades Cardiovasculares/genética , Mapeo Cromosómico , Cromosomas Humanos Par 1 , ADN Complementario/aislamiento & purificación , Femenino , Homocisteína/sangre , Humanos , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2) , Datos de Secuencia Molecular , Enfermedades del Sistema Nervioso/enzimología , Enfermedades del Sistema Nervioso/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/deficiencia , Linaje , Homología de Secuencia de Aminoácido , Porcinos
11.
Nat Genet ; 10(1): 111-3, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7647779

RESUMEN

Hyperhomocysteinaemia has been identified as a risk factor for cerebrovascular, peripheral vascular and coronary heart disease. Elevated levels of plasma homocysteine can result from genetic or nutrient-related disturbances in the trans-sulphuration or re-methylation pathways for homocysteine metabolism. 5, 10-Methylenetetrahydrofolate reductase (MTHFR) catalyzes the reduction of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, the predominant circulatory form of folate and carbon donor for the re-methylation of homocysteine to methionine. Reduced MTHFR activity with a thermolabile enzyme has been reported in patients with coronary and peripheral artery disease. We have identified a common mutation in MTHFR which alters a highly-conserved amino acid; the substitution occurs at a frequency of approximately 38% of unselected chromosomes. The mutation in the heterozygous or homozygous state correlates with reduced enzyme activity and increased thermolability in lymphocyte extracts; in vitro expression of a mutagenized cDNA containing the mutation confirms its effect on thermolability of MTHFR. Finally, individuals homozygous for the mutation have significantly elevated plasma homocysteine levels. This mutation in MTHFR may represent an important genetic risk factor in vascular disease.


Asunto(s)
Mutación , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/deficiencia , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Enfermedades Vasculares/genética , Adulto , Secuencia de Bases , ADN Complementario , Estabilidad de Enzimas , Escherichia coli/metabolismo , Femenino , Homocisteína/metabolismo , Humanos , Riñón/metabolismo , Hígado/metabolismo , Linfocitos/metabolismo , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2) , Persona de Mediana Edad , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Quebec , Factores de Riesgo , Temperatura , Enfermedades Vasculares/epidemiología
12.
J Bioeth Inq ; 20(4): 719-730, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38165556

RESUMEN

The issues and problems of mandatory vaccination policy and roll out in First Nations communities are unique and do not concern the safety and effectiveness of vaccines. These issues are also independent of more specific arguments of mandatory vaccination of healthcare workers as a condition of employment. As important as these issues are, they do not consider the complex politics of ongoing settler colonialism and First Nations community relations. In this paper, we also set aside the very real problems of disinformation, hesitancy, scientific and health illiteracy, and other concerns that drive vaccine hesitancy and refusal. These affect all communities, including First Nations communities. We, instead describe the dominant arguments in favour of mandatory vaccination and critique them in terms of the disputed legitimacy of Settler-Colonial decision-making as it impacts First Nations communities. We contend cultural responsiveness and safety-not state compulsion-must remain the first principles of any engagement-including vaccination-with First Nations Peoples, families, and communities.


Asunto(s)
Vacunación Obligatoria , Vacunas , Humanos , Vacunación , Personal de Salud , Disentimientos y Disputas
13.
J Neurosci Res ; 90(2): 376-87, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21959900

RESUMEN

The extracellular matrix surrounds different neuronal compartments in the mature nervous system. In a variety of vertebrates, most brain regions are loaded with a distinct type of extracellular matrix around the somatodendritic part of neurons, termed perineuronal nets. The present study reports that chondrotin sulfate proteoglycan-based matrix is structured differently in the human lateral geniculate body. Using various chondrotin sulfate proteoglycan-based extracellular matrix antibodies, we show that perisomatic matrix labeling is rather weak or absent, whereas dendrites are contacted by axonal coats appearing as small, oval structures. Confocal laser scanning microscopy and electron microscopy demonstrated that these typical structures are associated with synaptic loci on dendrites. Using multiple labelings, we show that different chondrotin sulfate proteoglycan components of the extracellular matrix do not associate exclusively with neuronal structures but possibly associate with glial structures as well. Finally, we confirm and extend previous findings in primates that intensity differences of various extracellular matrix markers between magno- and parvocellular layers reflect functional segregation between these layers in the human lateral geniculate body.


Asunto(s)
Agrecanos/metabolismo , Matriz Extracelular/metabolismo , Cuerpos Geniculados/metabolismo , Red Nerviosa/metabolismo , Nervios Periféricos/metabolismo , Anticuerpos , Proteoglicanos Tipo Condroitín Sulfato/inmunología , Dendritas/química , Dendritas/metabolismo , Matriz Extracelular/química , Cuerpos Geniculados/química , Cuerpos Geniculados/citología , Humanos , Red Nerviosa/química , Red Nerviosa/citología , Nervios Periféricos/química , Nervios Periféricos/citología
14.
J Immunol ; 184(2): 607-14, 2010 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-20007540

RESUMEN

Although CD8+ T cells are usually considered antitumoral, several recent studies report that the cells can also promote tumor progression. Using the melanoma cell line B16 as a murine model of pulmonary metastasis, we examined whether the pro- versus antitumoral effects of CD8+ T cells relate to their Ag specificity. Results of the study indicate that although CD8+ T cells specific for tumor Ags promote tumor rejection, CD8+ T cells specific for unrelated Ags promote tumor progression. We found the effect to be partly attributable to CD8+ T cells dampening effective antitumor NK cell responses. Notably, activation of CD8+ T cell responses by an unrelated stimulus, in this case infection with influenza virus, increased the number of pulmonary tumor nodules. These data provide a rationale for previously unexplained data identifying contrasting roles for CD8+ T cells in tumor progression.


Asunto(s)
Antígenos/inmunología , Linfocitos T CD8-positivos/inmunología , Melanoma/inmunología , Especificidad del Receptor de Antígeno de Linfocitos T/inmunología , Animales , Antígenos de Neoplasias/inmunología , Antígenos Virales/inmunología , Línea Celular Tumoral , Citotoxicidad Inmunológica , Progresión de la Enfermedad , Memoria Inmunológica , Células Asesinas Naturales/inmunología , Neoplasias Pulmonares/secundario , Ratones , Ovalbúmina/inmunología
15.
Osteoporos Int ; 22(4): 1263-74, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20559818

RESUMEN

UNLABELLED: Medicare claims data were used to investigate associations between history of previous fractures, chronic conditions, and demographic characteristics and occurrence of fractures at six anatomic sites. The study confirmed previously established associations for hip and spine fractures and identified several new associations of interest for nonhip, nonspine fractures. INTRODUCTION: This study investigates the associations of a history of fracture, comorbid chronic conditions, and demographic characteristics with incident fractures among Medicare beneficiaries. The majority of fracture incidence studies have focused on the hip and on white females. This study examines a greater variety of fracture sites and more population subgroups than prior studies. METHODS: We used Medicare claims data to examine the incidence of fracture at six anatomic sites in a random 5% sample of Medicare beneficiaries during the time period 2000 through 2005. RESULTS: For each type of incident fracture, women had a higher rate than men, and there was a positive association with age and an inverse association with income. Whites had a higher rate than nonwhites. Rates were lowest among African-Americans for all sites except ankle and tibia/fibula, which were lowest among Asian-Americans. Rates of hip and spine fracture were highest in the South, and fractures of other sites were highest in the Northeast. Fall-related conditions and depressive illnesses were associated with each type of incident fracture, conditions treated with glucocorticoids with hip and spine fractures and diabetes with ankle and humerus fractures. Histories of hip and spine fractures were associated positively with each site of incident fracture except ankle; histories of nonhip, nonspine fractures were associated with most types of incident fracture. CONCLUSIONS: This study confirmed previously established associations for hip and spine fractures and identified several new associations of interest for nonhip, nonspine fractures.


Asunto(s)
Fracturas Óseas/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Enfermedad Crónica/epidemiología , Métodos Epidemiológicos , Femenino , Fracturas Óseas/etiología , Fracturas de Cadera/epidemiología , Fracturas de Cadera/etiología , Humanos , Masculino , Medicare/estadística & datos numéricos , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Factores Sexuales , Factores Socioeconómicos , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/etiología , Estados Unidos/epidemiología
16.
Nat Med ; 2(9): 1017-21, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8782460

RESUMEN

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) produces clinical, biochemical and neuropathologic changes reminiscent of those which occur in idiopathic Parkinson's disease. 7-Nitroindazole (7-NI) is a relatively selective inhibitor of the neuronal isoform of nitric oxide synthase (NOS) that blocks MPTP neurotoxicity in mice. We now show that 7-NI protects against profound striatal dopamine depletions and loss of tyrosine hydroxylase-positive neurons in the substantia nigra in MPTP-treated baboons. Furthermore, 7-NI protected against MPTP-induced motor and frontal-type cognitive deficits. These results strongly implicate a role of nitric oxide in MPTP neurotoxicity and suggest that inhibitors of neuronal NOS might be useful in treating Parkinson's disease.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Indazoles/farmacología , Neuronas/enzimología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Enfermedad de Parkinson Secundaria/tratamiento farmacológico , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Ácido 3,4-Dihidroxifenilacético/metabolismo , Animales , Modelos Animales de Enfermedad , Dopamina/metabolismo , Ácido Homovanílico/metabolismo , Hipocinesia , Masculino , Actividad Motora , Examen Neurológico , Neuronas/efectos de los fármacos , Óxido Nítrico Sintasa/metabolismo , Papio , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/enzimología , Sustancia Negra/efectos de los fármacos , Sustancia Negra/enzimología , Grabación de Cinta de Video
17.
Nat Med ; 5(3): 347-50, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10086395

RESUMEN

Mitochondria are particularly vulnerable to oxidative stress, and mitochondrial swelling and vacuolization are among the earliest pathologic features found in two strains of transgenic amyotrophic lateral sclerosis (ALS) mice with SOD1 mutations. Mice with the G93A human SOD1 mutation have altered electron transport enzymes, and expression of the mutant enzyme in vitro results in a loss of mitochondrial membrane potential and elevated cytosolic calcium concentration. Mitochondrial dysfunction may lead to ATP depletion, which may contribute to cell death. If this is true, then buffering intracellular energy levels could exert neuroprotective effects. Creatine kinase and its substrates creatine and phosphocreatine constitute an intricate cellular energy buffering and transport system connecting sites of energy production (mitochondria) with sites of energy consumption, and creatine administration stabilizes the mitochondrial creatine kinase and inhibits opening of the mitochondrial transition pore. We found that oral administration of creatine produced a dose-dependent improvement in motor performance and extended survival in G93A transgenic mice, and it protected mice from loss of both motor neurons and substantia nigra neurons at 120 days of age. Creatine administration protected G93A transgenic mice from increases in biochemical indices of oxidative damage. Therefore, creatine administration may be a new therapeutic strategy for ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Creatina/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Alanina/genética , Alanina/fisiología , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Animales , Creatina/administración & dosificación , Creatina/metabolismo , Modelos Animales de Enfermedad , Glicina/genética , Glicina/fisiología , Humanos , Ratones , Ratones Transgénicos , Actividad Motora , Músculo Esquelético/fisiopatología , Neuronas/citología , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/metabolismo , Superóxido Dismutasa/genética , Superóxido Dismutasa/fisiología , Superóxido Dismutasa-1 , Tirosina/análogos & derivados , Tirosina/metabolismo , Tirosina 3-Monooxigenasa/metabolismo
18.
Haematologica ; 95(3): 514-7, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20207849

RESUMEN

Studies of the role of individual genes in chronic lymphocytic leukemia (CLL) have been hampered by the inability to consistently transfect primary tumor cells. Here, we describe a highly efficient method of genetically modifying primary CLL cells using a VSVG pseudotyped lentiviral vector. We transduced CD38 negative CLL cells with a lentiviral vector encoding CD38 which caused increased surface CD38 expression in all the samples tested (n=17) with no evidence of plasmacytoid differentiation. The mean percentage of positive cells expressing CD38 was 87%+/-8.5% and the mean cell viability 74%+/-17%. This high level of transduction of all the CLL cell samples tested demonstrates the utility of this technique which should prove applicable for the introduction and analysis of other genes in these non-dividing cells.


Asunto(s)
ADP-Ribosil Ciclasa 1/genética , Regulación Leucémica de la Expresión Génica , Vectores Genéticos/genética , Lentivirus/genética , Leucemia Linfocítica Crónica de Células B/genética , Glicoproteínas de Membrana/genética , Transducción Genética , ADP-Ribosil Ciclasa 1/metabolismo , Proliferación Celular , Citometría de Flujo , Humanos , Glicoproteínas de Membrana/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA