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1.
Eur J Orthop Surg Traumatol ; 25(4): 655-60, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25260576

RESUMEN

Cemented Thompson's prostheses have been used to treat elderly patients with displaced intracapsular hip fractures at our two units for the last 15 years, amid growing support for the use of newer implant designs for hip hemiarthroplasty. This provided us with an opportunity to investigate survival of the Thompson's stem in our patients. A retrospective cohort study was set up to review previously collected data on patients who underwent Thompson's hemiarthroplasty over a 7-year period. These were linked to surgical notes, clinical letters and radiographs to record post-operative course and subsequent admissions and procedures. The identifiers were then linked to mortality data from the Office of 'National Statistics. Kaplan-Meier survival analyses were done for implants and patients. A total of 1,632 patients (mean age 82.7 years) underwent 1,670 procedures. Five-year implant survival was 95.4 %. A total of 36 stems were revised, including 14 revisions to total hip arthroplasty and 22 excision arthroplasties. Reasons for revision included infection (2.1 %), dislocation (1.1 %) and aseptic loosening (0.5 %). Symptomatic aseptic loosening and acetabular erosion occurred late (mean time 3.2 and 5.7 years, respectively following surgery). Aseptic loosening and erosion following hemiarthroplasty are relatively late complications.


Asunto(s)
Artroplastia de Reemplazo de Cadera/métodos , Cementos para Huesos/uso terapéutico , Fracturas del Cuello Femoral/cirugía , Hemiartroplastia/métodos , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Cadera/mortalidad , Fracturas del Cuello Femoral/diagnóstico por imagen , Fracturas del Cuello Femoral/mortalidad , Hemiartroplastia/mortalidad , Prótesis de Cadera , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Falla de Prótesis , Infecciones Relacionadas con Prótesis/diagnóstico por imagen , Infecciones Relacionadas con Prótesis/mortalidad , Radiografía , Reoperación/mortalidad , Estudios Retrospectivos
2.
Infect Dis Ther ; 11(6): 2063-2098, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36229765

RESUMEN

INTRODUCTION: This guideline was written by a multidisciplinary committee with mandated members of the Dutch Society for Infectious Diseases, Dutch Society for Hematology, Dutch Society for Medical Oncology, Dutch Association of Hospital Pharmacists, Dutch Society for Medical Microbiology, and Dutch Society for Pediatrics. The guideline is written for adults and pediatric patients. METHOD: The recommendations are based on the answers to nine questions formulated by the guideline committee. To provide evidence-based recommendations we used all relevant clinical guidelines published since 2010 as a source, supplemented with systematic searches and evaluation of the recent literature (2010-2020) and, where necessary, supplemented by expert-based advice. RESULTS: For adults the guideline distinguishes between high- and standard-risk neutropenia based on expected duration of neutropenia (> 7 days versus ≤ 7 days). Where possible a distinction has been made between pediatric and adult patients. CONCLUSION: This guideline was written to aid diagnosis and management of patients with febrile neutropenia due to chemotherapy in the Netherlands. The guideline provides recommendation for children and adults. Adults patient are subdivided as having a standard- or high-risk neutropenic episode based on estimated duration of neutropenia. The most important recommendations are as follows. In adults with high-risk neutropenia (duration of neutropenia > 7 days) and in children with neutropenia, ceftazidime, cefepime, and piperacillin-tazobactam are all first-choice options for empirical antibiotic therapy in case of fever. In adults with standard-risk neutropenia (duration of neutropenia ≤ 7 days) the MASCC score can be used to assess the individual risk of infectious complications. For patients with a low risk of infectious complications (high MASCC score) oral antibiotic therapy in an outpatient setting is recommended. For patients with a high risk of infectious complications (low MASCC score) antibiotic therapy per protocol sepsis of unknown origin is recommended.

3.
J Med Genet ; 47(10): 686-91, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20543203

RESUMEN

BACKGROUND: CBL missense mutations have recently been associated with juvenile myelomonocytic leukaemia (JMML), an aggressive myeloproliferative and myelodysplastic neoplasm of early childhood characterised by excessive macrophage/monocyte proliferation. CBL, an E3 ubiquitin ligase and a multi-adaptor protein, controls proliferative signalling networks by downregulating the growth factor receptor signalling cascades in various cell types. METHODS AND RESULTS: CBL mutations were screened in 65 patients with JMML. A homozygous mutation of CBL was found in leukaemic cells of 4/65 (6%) patients. In all cases, copy neutral loss of heterozygosity of the 11q23 chromosomal region, encompassing the CBL locus, was demonstrated. Three of these four patients displayed additional features suggestive of an underlying developmental condition. A heterozygous germline CBL p.Y371H substitution was found in each of them and was inherited from the father in one patient. The germline mutation represents the first hit, with somatic loss of heterozygosity being the second hit positively selected in JMML cells. The three patients display a variable combination of dysmorphic features, hyperpigmented skin lesions and microcephaly that enable a 'CBL syndrome' to be tentatively delineated. Learning difficulties and postnatal growth retardation may be part of the phenotype. CONCLUSION: A report of germline mutations of CBL in three patients with JMML is presented here, confirming the existence of an unreported inheritable condition associated with a predisposition to JMML.


Asunto(s)
Mutación de Línea Germinal , Trastornos del Crecimiento , Leucemia Mielomonocítica Juvenil/genética , Microcefalia , Proteínas Proto-Oncogénicas c-cbl/genética , Niño , Preescolar , Discapacidades del Desarrollo/complicaciones , Discapacidades del Desarrollo/genética , Femenino , Predisposición Genética a la Enfermedad , Trastornos del Crecimiento/complicaciones , Trastornos del Crecimiento/genética , Humanos , Leucemia Mielomonocítica Juvenil/complicaciones , Masculino , Microcefalia/complicaciones , Microcefalia/genética , Síndrome
5.
Ann R Coll Surg Engl ; 99(4): e115-e117, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28349756

RESUMEN

Extruded talus is a rare serious result from a high-energy injury to a supinated and plantar flexed foot. Treatment remains controversial with a lack of congruent evidence for talar reimplantation. A 34-year-old woman was involved in a road traffic accident at 40 mph. Imaging revealed a left talus extruded anterolaterally with a talar neck fracture. Additional injuries included right acetabular fracture, transverse process fractures and rib fractures, which were treated conservatively. The talus was reimplanted and the talar neck fixed with a cortical screw. A hindfoot nail was used to fuse the calcaneus, talus and tibia. Follow-up at two years showed solid tibiotalocalcaneal fusion, with no evidence of avascular development, and the patient was fully weight bearing without pain. We believe this is the first published case of successful primary tibiotalocalcaneal fusion for extruded talus injuries.


Asunto(s)
Fracturas de Tobillo/cirugía , Traumatismos del Tobillo/cirugía , Articulación del Tobillo/cirugía , Artrodesis/métodos , Tornillos Óseos , Reimplantación/métodos , Astrágalo/lesiones , Accidentes de Tránsito , Acetábulo/lesiones , Adulto , Calcáneo/cirugía , Femenino , Humanos , Traumatismo Múltiple , Fracturas de las Costillas , Articulación Talocalcánea/cirugía , Astrágalo/cirugía , Tibia/cirugía
6.
Clin Oncol (R Coll Radiol) ; 18(4): 338-44, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16703753

RESUMEN

AIMS: Paclitaxel, a radiosensitiser, has significant activity in oesophageal cancer. We aimed to conduct a feasibility study of preoperative chemoradiation using paclitaxel, cisplatin and 5-fluorouracil (5-FU). MATERIALS AND METHODS: Sixteen eligible patients were enrolled. Infusional 5-FU, paclitaxel and cisplatin were given for 6 weeks before and concurrent with radiation. Conformal radiotherapy was delivered in two phases (45 Gy in 25 fractions). RESULTS: A total of 62.5% of the patients experienced Grade 3-4 toxicities, 50% required admission; one patient died during the neo-adjuvant phase. Twelve (75%) patients had oesophagectomy, and two (12.5%) died after surgery. Pathological complete remission (PCR) and minimal residual disease were observed in 25% (95% CI 0.5-49.5%) and 18% (95% CI 0-38%) of patients, respectively, who underwent surgery. The median survival was 39.7 months (95% CI 15, not reached); 1-, 2-, 3-, and 4-year survivals were 75% (95% CI 56.5-99.5), 56.3% (36.5-86.7), 50% (30.6-81.6), and 50% (30.6-81.6), respectively. CONCLUSION: Paclitaxel, cisplatin and 5-FU (TCF)-chemoradiation is an active regimen; the current dose schedule tested is associated with unacceptable toxicity, and cannot be recommended for routine clinical use.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Esofágicas/tratamiento farmacológico , Terapia Neoadyuvante , Cuidados Preoperatorios , Adenocarcinoma/radioterapia , Adenocarcinoma/cirugía , Adulto , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/cirugía , Estudios de Factibilidad , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos , Estudios Prospectivos , Radioterapia Conformacional , Análisis de Supervivencia
7.
Diabetes ; 28(10): 949-51, 1979 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-478186

RESUMEN

The distribution of phenotypes controlled by two loci on chromosome 6 has been studied in a series of 239 patients with type 1 (insulin-dependent) and 297 patients with type 2 (non-insulin-dependent) diabetes mellitus. At the properdin factor B (Bf) locus there is a significant increase in the frequency of the BfSu and BfF1 alleles for type 1 patients, and the combined inc;rease in frequency of BfS1 and BfF1 in those patients is highly significant. The relative risk for F1 is 6.2 and for F1 and S1 combined is 5.3. These results confirm the association with F1 reported recently by Raum and co-workers in Boston. The two rare alleles BfS1 and BfF1 are in significant negative disequilibrium with HLA B8. For the glyoxalase (GLO) locus there is a slight but nonsignificant increase in the frequency of the GLO2 allele, but a significant disturbance in the distribution of the GLO phenotypes for type 2 patients. These results for the GLO alleles may be due to stratification in our series of type 2 patients. Further studies are in progress to test this hypothesis.


Asunto(s)
Factor B del Complemento/genética , Diabetes Mellitus/genética , Precursores Enzimáticos/genética , Lactoilglutatión Liasa/genética , Liasas/genética , Alelos , Cromosomas Humanos 6-12 y X , Frecuencia de los Genes , Humanos , Fenotipo
8.
Diabetes ; 30(1): 26-9, 1981 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7014302

RESUMEN

Cold-reacting serum lymphocytotoxic antibodies (LCAs) were measured in sera from 230 insulin-dependent juvenile-onset diabetes mellitus (IDDM) patients and from 116 control subjects. LCAs were present in only 4% of control sera compared with 19% in IDDM patients. The most significant determinant of LCAs was time since onset of diabetes; within the first 12 mo, 55% of IDDM sera had LCAs, compared with 25% after one year and 15% after five years of diabetes. LCAs were absent in sera from patients with IDDM for 10 yr or more. Genetic factors were also implicated in susceptibility toi occurrence of LCAs. HLA antigen B8 and B18 were associated with an increased risk for LCAs, whereas HLA-B7 was associated with a decreased risk. The relative risk for LCAs in patients positive for HLA-B8 but not B7 was 2.3, compared with 0.0 in HLA-B7/B8 heterozygotes. In contrast, B7 did not provide protection from LCAs in B18/B7 IDDM patients. Properdin factor B (Bf) alleles, which are in linkage disequilibrium with alleles of the HLA-B locus, were also associated with LCAs, IDDM patients with alleles BfS1 or BfF hd a prevalence of LCAs of 7%, significantly less than the 39% in Bf-F1S or -F1 patients. LCAs were not identical or closely correlated to pancreatic islet cell antibodies. Our findings indicate genetic heterogeneity in, yet, another autoimmune process in IDDM.


Asunto(s)
Suero Antilinfocítico/análisis , Diabetes Mellitus Tipo 1/inmunología , Antígenos HLA/análisis , Adolescente , Citotoxicidad Celular Dependiente de Anticuerpos , Niño , Preescolar , Humanos , Anticuerpos Insulínicos/análisis , Islotes Pancreáticos/inmunología , Fenotipo
9.
Diabetes ; 38(6): 779-83, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2656346

RESUMEN

A double-blind controlled trial of azathioprine (2 mg.kg-1.day-1) was conducted with 49 patients aged 2-20 yr (mean 10.8 yr) who had newly diagnosed type I (insulin-dependent) diabetes. Patients were randomly assigned to receive either azathioprine (n = 24) or placebo (n = 25) for 12 mo, beginning within the 20-day period after diagnosis. Baseline clinical and metabolic characteristics did not differ between the two groups. No patient experienced complete remission, defined as restoration of normal carbohydrate tolerance without other treatment. Partial remission, defined as good metabolic control (hemoglobin A1c less than or equal to 7.9%, preprandial blood glucose less than or equal to 8 mM with an insulin dose of less than 0.5 U.kg-1.day-1), occurred in 10 placebo (40%) and 7 azathioprine (29%) patients at 6 mo and in 4 placebo (16%) and 4 azathioprine (17%) patients at 12 mo (differences not significant). Fasting plasma C-peptide was significantly greater in the azathioprine-treated group at 3 and 6 mo, but this difference was not sustained. C-peptide responses to a standard meal and the frequency of islet cell and insulin antibodies did not differ between the two groups over the 12-mo period. Azathioprine caused no significant side effects. We conclude that in the dosage used, and despite early effects on endogenous insulin secretion, azathioprine alone does not influence the remission phase in children with newly diagnosed type I diabetes.


Asunto(s)
Azatioprina/uso terapéutico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Glucemia/análisis , Péptido C/sangre , Niño , Ensayos Clínicos como Asunto , Diabetes Mellitus Tipo 1/sangre , Método Doble Ciego , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/análisis , Humanos , Insulina/uso terapéutico , Masculino
10.
Pharmacol Ther ; 52(3): 423-43, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1687928

RESUMEN

The neurotransmitter deficits of dementias, including Alzheimer's dementia, Lewy body dementia and Parkinson's disease are discussed in relation to cognitive and behavioural impairments together with neuropathological changes and available data on the status of receptor transmembrane signalling. Potential therapeutic strategies for dementia are outlined based on the following systems: excitatory amino acids, gamma-amino butyric acid, acetylcholine (muscarinic and nicotinic), noradrenaline, serotonin and peptides. These include the attenuation of transmitter deficits by agonists and agents inhibiting transmitter breakdown and support for surviving neurons by suppression of inhibitory inputs, trophic factors and neural implantation.


Asunto(s)
Demencia/tratamiento farmacológico , Neuroquímica , Neurotransmisores/uso terapéutico , Parasimpatolíticos/uso terapéutico , Animales , Inhibidores de la Colinesterasa/uso terapéutico , Demencia/prevención & control , Humanos , Inhibidores de la Monoaminooxidasa/uso terapéutico , Receptores Muscarínicos/efectos de los fármacos , Receptores Nicotínicos/efectos de los fármacos
11.
Pharmacogenetics ; 8(2): 125-8, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10022750

RESUMEN

The dopamine D2 receptor gene contains a TaqI repeat fragment length polymorphism creating two alleles DRD2*A1 and DRD2*A2. It has been previously suggested that the lesser allele, DRD2*A1, is more prevalent in individuals who are susceptible to impulsive/addictive/compulsive behaviour, for example, alcoholics, polysubstance abusers and tobacco smokers. We genotyped a series of 104 smokers and 117 non smokers and compared the allele frequencies between the groups. A subset (n = 87) of the smoking population also completed the Classification of Smoking by Motives questionnaire and were given scores for five criteria that drive smoking: automatic, dependence, sedative, stimulant and indulgence. Another subset (n = 52) completed the Fagerstrom Tolerance Questionnaire and were given scores for nicotine dependence. We did not find any increase in allele A1 frequency when comparing smokers to non smokers. Furthermore, neither measure of dependence was affected by possession of the A1 allele; the only difference between DRD2*A1 bearing and DRD2*A2 homozygous individuals in terms of smoking motives was found in the scores for indulgence; the former having a moderately reduced score (by 17%, p < 0.05). We conclude that, in the individuals studied, the dopamine D2 receptor TaqI locus does not affect the drive to smoke. This may be caused by the locus being unrelated to impulsive/addictive/compulsive behaviour, the polymorphism being in linkage disequilibrium with another distinct locus or, alternatively, smoking may represent a behaviour that is not directly comparable to impulsive/addictive/compulsive behaviours previously associated with the DRD2*A1 allele.


Asunto(s)
Frecuencia de los Genes , Receptores de Dopamina D2/genética , Fumar/genética , Alelos , Secuencia de Bases , Cartilla de ADN , Predisposición Genética a la Enfermedad , Heterocigoto , Homocigoto , Humanos , Motivación , Encuestas y Cuestionarios , Reino Unido
12.
Pharmacogenetics ; 7(6): 479-84, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9429233

RESUMEN

The relationship between a dopamine D2 receptor genetic polymorphism at the Taq1 A locus and the level of D2 receptor binding was investigated in normal, middle aged to elderly subjects with no psychiatric or neurological disorders. D2 receptor binding was measured by autoradiography in the caudate, putamen and nucleus accumbens, using the specific D2 receptor ligand [3H]-raclopride. In a sample of 44 individuals, only one was homozygous for the A1 allele, 25 were homozygous for A2 and 18 were heterozygotes. The presence of one or two A1 alleles was associated with reduced D2 receptor binding in all areas of the striatum, reaching statistical significance in the ventral caudate and putamen (p = 0.01 and p = 0.044, respectively). This reduction was more marked in males than females, particularly in the putamen. A genetic predisposition to lower D2 receptor expression may increase susceptibility to neuroleptic medication or clinical symptoms that are associated with diseases involving dopaminergic pathology.


Asunto(s)
Alelos , Cuerpo Estriado/metabolismo , Polimorfismo Genético/genética , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/metabolismo , Polimerasa Taq/genética , Anciano , Anciano de 80 o más Años , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
13.
Acta Neurol Scand Suppl ; 176: 34-41, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11261803

RESUMEN

OBJECTIVES: Comparisons were made of nicotinic receptors in 3 major forms of dementia in old age. Although it is well established the involvement of nicotinic receptors in Alzheimer's disease (AD), their status in the other two main causes of dementia in old age-dementia with Lewy bodies (DLB) and vascular dementia (VaD) is not widely reported. METHODS: Temporal cortex was examined for epibatidine and alpha-bungarotoxin binding, and immunoreactivity of alpha4 and alpha7 nAChR subunits. RESULTS: There were selective abnormalities in nicotinic receptor subtypes in the disorders examined. In AD there is a loss of high affinity receptor binding, reflecting a selective loss of alpha4 subunit, but no change in alpha7 subunits. Similar abnormalities in ligand binding are also apparent in DLB. In the VaD series, there was no overall loss of epibatidine binding or immunoreactivity for alpha4 or alpha7 subunits. CONCLUSIONS: Loss of cortical receptor alpha4 subunit appears to be a characteristic feature of neurodegenerative dementia but not dementia of vascular origin. Since nicotinic receptors control cerebral vasodilation, the relative integrity of the receptors in VaD may auger well for nicotinic therapy in this disorder in which there is a cholinergic abnormality, to judge by the loss of the presynaptic enzyme.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Demencia Vascular/fisiopatología , Enfermedad por Cuerpos de Lewy/fisiopatología , Receptores Nicotínicos/análisis , Lóbulo Temporal/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunoquímica , Ligandos , Masculino , Receptores Nicotínicos/metabolismo , Fumar , Lóbulo Temporal/irrigación sanguínea , Vasodilatación
14.
Biol Psychiatry ; 49(3): 175-84, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11230868

RESUMEN

Loss of cortical nicotinic acetylcholine receptors with high affinity for agonists (20-50%) in patients with Alzheimer's disease is a common finding. Recent immunochemical analyses indicate that this deficit is predominantly associated with the loss of alpha4 subunits (30-50%), although modest reductions of alpha3 may occur in some individuals (25-29%). No reduction of beta2 subunit protein expression or levels of alpha3 and alpha4 messenger RNA has been reported. Decline in cortical [(125)I]alpha-bungarotoxin binding and alpha7 protein expression does not appear to be as extensive or widespread as the loss of alpha4 (0-40%), with no reduction in messenger RNA expression. In the thalamus, there was a trend for reduced [(3)H]nicotine binding in the majority of nuclei (0-20%) in Alzheimer's disease; however, there was a significant decline in [(125)I]alpha-bungarotoxin binding in the reticular nucleus. In the striatum [(3)H]nicotine binding was reduced in Alzheimer's disease, and although neuroleptic medication accentuated this change, it occurred in those free of neuroleptics. Changes in nicotinic acetylcholine receptors in Alzheimer's disease are distinct from those in normal aging and are likely to contribute to clinical features and possibly neuropathology.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Encéfalo/fisiopatología , Receptores Nicotínicos/fisiología , Anciano , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/patología , Ganglios Basales/patología , Ganglios Basales/fisiopatología , Encéfalo/patología , Mapeo Encefálico , Corteza Cerebral/patología , Corteza Cerebral/fisiopatología , Humanos , Receptores Nicotínicos/clasificación , Tálamo/patología , Tálamo/fisiopatología
15.
Biol Psychiatry ; 44(8): 765-74, 1998 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-9798081

RESUMEN

BACKGROUND: In dementia with Lewy bodies (DLB) mild extrapyramidal symptoms are associated with moderate reductions in substantia nigra neuron density and concentration of striatal dopamine. Many DLB patients treated with typical neuroleptics suffer severe adverse reactions, which result in decreased survival. METHODS: In a series of DLB cases, with and without neuroleptic sensitivity, substantia nigra neuron densities, striatal dopamine and homovanillic acid concentrations, and autoradiographic [3H]mazindol and [3H]raclopride binding (to the dopamine transporter and D2 receptor, respectively) were analyzed and compared to control and idiopathic Parkinson's disease cases. RESULTS: D2 receptors were up-regulated in neuroleptictolerant DLB and Parkinson's disease compared to DLB without neuroleptic exposure and controls. D2 receptors were not up-regulated in DLB cases with severe neuroleptic reactions. Dopamine uptake sites were reduced concomitantly with substantia nigra neuron density in Parkinson's disease compared to controls, but there was no significant correlation between substantia nigra neuron density and [3H]mazindol binding in DLB groups. There was no significant difference in substantia nigra neuron density, [3H]mazindol binding, and dopamine or homovanillic acid concentration between neuroleptic-tolerant and -sensitive groups. CONCLUSIONS: Failure to up-regulate D2 receptors in response to neuroleptic blockade or reduced dopaminergic innervation may be the critical factor responsible for neuroleptic sensitivity.


Asunto(s)
Antipsicóticos/uso terapéutico , Dopamina/metabolismo , Neostriado/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Sustancia Negra/metabolismo , Adulto , Antipsicóticos/efectos adversos , Autorradiografía , Encéfalo/patología , Química Encefálica/efectos de los fármacos , Química Encefálica/fisiología , Recuento de Células , Femenino , Ácido Homovanílico/metabolismo , Humanos , Masculino , Neostriado/patología , Neuronas/metabolismo , Enfermedad de Parkinson/patología , Receptores de Dopamina D2/metabolismo , Sustancia Negra/patología
16.
Neurobiol Aging ; 17(4): 639-51, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8832639

RESUMEN

Distinct patterns of age-related alterations in NMDA (MK801 binding) and non-NMDA, AMPA (CNQX), and kainate binding have been identified in human hippocampus and parahippocampal gyrus in normal individuals with no evidence of degenerative brain disease ranging in age from 24 gestational weeks to 94 years. Whereas MK801 binding did not alter substantially over this age range, CNQX binding rose from low levels in the fetus to maximum levels between neonate and middle age, and kainate binding declined extensively from the perinatal to adult stage. Following maturity, there were no significant changes in kainate binding, although MK801 binding increased in CA1 and CA3 and CNQX binding declined in several regions, particularly CA2 and subiculum. For each receptor binding the timing of these fluctuations ocurring during development and aging varied within different regions of the dentate gyrus, hippocampus proper, subicular complex, and entorhinal cortex examined. The transient peaks of receptor binding are likely to reflect processes of synaptogenesis and pruning and may provide clues regarding the role of the different glutamate receptor subtypes in various pathologies of the hippocampus and adjacent cortex associated with developmental disorders (of genetic origin or due to perinatal trauma or insult). The absence of substantial changes in any subtype examined from middle to old age suggests alterations in transmitter binding to these glutamate receptors are not involved in senescent neurodegeneration.


Asunto(s)
Envejecimiento/metabolismo , Corteza Cerebral/metabolismo , Hipocampo/metabolismo , Receptores de Glutamato/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Unión Competitiva , Niño , Preescolar , Humanos , Persona de Mediana Edad
17.
Neurobiol Aging ; 13(3): 393-400, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1625768

RESUMEN

Choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) activities have been examined postmortem in a series of 66 individuals with no evidence of CNS disease, ranging in age from 24 gestational weeks to 95 years and in 33 cases of Alzheimer's disease (AD) aged 57-89 years. In the normal human hippocampus a striking and highly significant age-related decline in ChAT occurred from middle to old age (between 40 and 100 years); a trend apparent at a later stage and to a lesser extent in the hippocampal gyrus. In both areas enzyme activity in AD was inversely related to age at death; reductions compared with the normal were on average 70-80% in the 60-70 year old groups compared with 30-40% in the 80-90 year old group. A similar trend was apparent with respect to acetylcholinesterase (AchE) histochemical activity associated with fibers and terminals (predominantly cholinergic and concentrated in CA3 and 4 of the hippocampus) but not with reactive perikarya (considered to be noncholinergic) present in both hippocampus and cortex. These data indicate that the normal aging human hippocampus may constitute a useful model for investigating the dysfunction or degeneration of basal forebrain cholinergic neurons in AD.


Asunto(s)
Acetilcolinesterasa/análisis , Envejecimiento/metabolismo , Enfermedad de Alzheimer/metabolismo , Colina O-Acetiltransferasa/análisis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Hipocampo/química , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Tinción con Nitrato de Plata
18.
Am J Psychiatry ; 158(7): 1058-66, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11431227

RESUMEN

OBJECTIVE: Measures of cholinergic transmitter activity were investigated in patients with autism because of reported neuropathological abnormalities in cholinergic nuclei in the basal forebrain. METHOD: Levels of cholinergic enzyme and receptor activity were measured in the frontal and parietal cerebral cortex of deceased autistic adults, similarly aged normal adults without mental retardation, and nonautistic mentally retarded adults. The immunoreactivity levels of brain-derived neurotrophic factor and nerve growth factor were measured in the basal forebrain. RESULTS: There were no differences between the autistic and comparison groups in choline acetyltransferase or acetylcholinesterase activity in the cerebral cortex and basal forebrain or in muscarinic M(2) receptor or alpha-bungarotoxin binding within the cortex. Cortical M(1) receptor binding was up to 30% lower than normal in the autistic subjects, and the difference reached significance in the parietal cortex. In both the parietal and frontal cortices, differences in nicotinic receptors assessed by [(3)H]epibatidine binding were significant and extensive (65%-73% lower in the autistic group than in the normal subjects); there were no differences in nicotine binding in the basal forebrain. Immunochemical analysis indicated lower levels of both the alpha(4) and beta(2) nicotinic receptor subunits in the parietal cortex. The M(1) receptor abnormality was not evident in the nonautistic group with mental retardation, although the lower [(3)H]epibatidine binding was apparent. In the basal forebrain, the level of brain-derived neurotrophic factor in the autistic group was three times as high as the level of the normal group. CONCLUSIONS: These neurochemical abnormalities implicate the cholinergic system in developmental disorders such as autism and suggest the potential for intervention based on cholinergic receptor modulation.


Asunto(s)
Acetilcolinesterasa/análisis , Trastorno Autístico/diagnóstico , Corteza Cerebral/química , Corteza Cerebral/enzimología , Colina O-Acetiltransferasa/análisis , Prosencéfalo/química , Prosencéfalo/enzimología , Receptores Colinérgicos/análisis , Acetilcolinesterasa/metabolismo , Adulto , Trastorno Autístico/metabolismo , Autorradiografía/métodos , Biomarcadores , Colina O-Acetiltransferasa/metabolismo , Síndrome de Down/diagnóstico , Síndrome de Down/metabolismo , Lóbulo Frontal/química , Lóbulo Frontal/metabolismo , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/metabolismo , Nicotina/metabolismo , Ácidos Nipecóticos/análisis , Ácidos Nipecóticos/metabolismo , Lóbulo Parietal/química , Lóbulo Parietal/metabolismo , Piperazinas/análisis , Piperazinas/metabolismo , Receptores Colinérgicos/metabolismo , Receptores Muscarínicos/análisis , Receptores Muscarínicos/metabolismo , Receptores Nicotínicos/análisis
19.
Am J Clin Nutr ; 34(9): 1804-10, 1981 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7282606

RESUMEN

Studies were made of steroid metabolites excreted in the urine of 17 obese girls 11.4 to 16.8 yr and 17 normal girls 11 to 17 yr. Creatinine excretion (muscle mass), total body water (or deuterium space), lean body mass and body fat were determined in the obese girls. Extracellular volume (corrected bromide space) was also measured and by difference with body water, intracellular water or soft tissue cell mass was calculated. In normal girls 24-h creatinine excretion was determined, but body water was predicted from height and weight. It was found, as in previous studies, that the obese girls had excess muscle mass and soft tissue cell mass for height. The excess growth of muscle, lean tissue, and body length in obese girls correlated with increments in oxosteroid (17 ketosteroid) excretion. The overall weight increase correlated with increased excretion of corticosteroid metabolites--a finding of interest since a physiological Cushing's syndrome was postulated for fat girls many years ago. When the normal and obese girls were divided by age at 14 yr and the subgroups compared (normal obese) the younger girls showed differences with respect to height, weight, total body water, fat and percentage fat. Differences in steroid metabolites were not found. In older girls the same findings were made again, but here it was clear that the increments in body size, particularly muscle mass, correlated with augmented oxosteroid excretion. Evidence is cited that these findings are not just related to a larger steroid pool in obese girls.


Asunto(s)
17-Cetosteroides/orina , Composición Corporal , Obesidad/orina , Pregnanos/orina , Adolescente , Corticoesteroides/orina , Agua Corporal/análisis , Peso Corporal , Niño , Creatinina/orina , Femenino , Humanos , Obesidad/patología , Pubertad
20.
Curr Drug Targets CNS Neurol Disord ; 1(4): 387-97, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12769611

RESUMEN

Mapping of nicotinic acetylcholine receptor (nAChR) subtypes and subunits in human brain is far from complete, however it is clear that multiple subunits are present (including alpha3, alpha4, alpha5, alpha6 and alpha7, beta2, alpha3 and beta4) and that these receptors are not solely distributed on neurones, but also on cerebral vasculature and astrocytes. It is important to elucidate subunit composition of receptors associated with different cell types and pathways within the human CNS in terms of potential nicotinic therapy for a range of both developmental and age-related disorders in which nAChR attenuation occurs. Reductions in nAChRs are reported in Alzheimer's and Parkinson's diseases, dementia with Lewy bodies, schizophrenia and autism, but may not be associated with reduced cortical cholinergic innervation observed in vascular dementia or occur at an early stage in Down's syndrome. Changes in nAChR expression in neuropsychiatric disorders appear to be brain region and subtype specific and have been shown in some instances to be associated with pathology and symptomatology. It is likely that deficits in alpha4-containing receptors predominate in cortical areas in Alzheimer's disease and autism, whereas reduction of alpha7 receptors may be more important in schizophrenia. Changes in astrocytic and vascular nAChR expression in neurodegenerative diseases should also be considered. Studies using both animal models and human autopsy tissue suggest that nAChRs can play a role in neuroprotection against age-related pathology. It is possible that the development of nAChR subtype specific drugs may lead to advances in therapy for both age-related and psychiatric disorders.


Asunto(s)
Química Encefálica/fisiología , Trastornos Mentales/fisiopatología , Enfermedades del Sistema Nervioso/fisiopatología , Receptores Nicotínicos/fisiología , Envejecimiento/fisiología , Animales , Química Encefálica/efectos de los fármacos , Humanos , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Receptores Nicotínicos/efectos de los fármacos , Receptores Nicotínicos/metabolismo
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