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1.
Syst Rev ; 12(1): 191, 2023 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-37805577

RESUMEN

BACKGROUND AND OBJECTIVE: Since 1997, several meta-analyses (MAs) of placebo-controlled randomised efficacy trials of homoeopathy for any indication (PRETHAIs) have been published with different methods, results and conclusions. To date, a formal assessment of these MAs has not been performed. The main objective of this systematic review of MAs of PRETHAIs was to evaluate the efficacy of homoeopathic treatment. METHODS: The inclusion criteria were as follows: MAs of PRETHAIs in humans; all ages, countries, settings, publication languages; and MAs published from 1 Jan. 1990 to 30 Apr. 2023. The exclusion criteria were as follows: systematic reviews without MAs; MAs restricted to age or gender groups, specific indications, or specific homoeopathic treatments; and MAs that did not assess efficacy. We searched 8 electronic databases up to 14 Dec. 2020, with an update search in 6 databases up to 30 April 2023. The primary outcome was the effect estimate for all included trials in each MA and after restricting the sample to trials with high methodological quality, according to predefined criteria. The risk of bias for each MA was assessed by the ROBIS (Risk Of Bias In Systematic reviews) tool. The quality of evidence was assessed by the GRADE framework. Statistical analyses were performed to determine the proportion of MAs showing a significant positive effect of homoeopathy vs. no significant difference. RESULTS: Six MAs were included, covering individualised homoeopathy (I-HOM, n = 2), nonindividualised homoeopathy (NI-HOM, n = 1) and all homoeopathy types (ALL-HOM = I-HOM + NI-HOM, n = 3). The MAs comprised between 16 and 110 trials, and the included trials were published from 1943-2014. The median trial sample size ranged from 45 to 97 patients. The risk of bias (low/unclear/high) was rated as low for three MAs and high for three MAs. Effect estimates for all trials in each MA showed a significant positive effect of homoeopathy compared to placebo (5 of 5 MAs, no data in 1 MA). Sensitivity analyses with sample restriction to high-quality trials were available from 4 MAs; the effect remained significant in 3 of the MAs (2 MAs assessed ALL-HOM, 1 MA assessed I-HOM) and was no longer significant in 1 MA (which assessed NI-HOM). DISCUSSION: The quality of evidence for positive effects of homoeopathy beyond placebo (high/moderate/low/very low) was high for I-HOM and moderate for ALL-HOM and NI-HOM. There was no support for the alternative hypothesis of no outcome difference between homoeopathy and placebo. The available MAs of PRETHAIs reveal significant positive effects of homoeopathy beyond placebo. This is in accordance with laboratory experiments showing partially replicable effects of homoeopathically potentised preparations in physico-chemical, in vitro, plant-based and animal-based test systems. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42020209661. The protocol for this SR was finalised and submitted on 25 Nov. 2020 and registered on 26 Dec. 2020.


Asunto(s)
Homeopatía , Humanos , Sesgo , Proyectos de Investigación , Metaanálisis como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
Cancer Res ; 52(15): 4277-9, 1992 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-1353411

RESUMEN

Previous studies have shown frequent allelic losses of chromosomes 9p, 10, 17p, and 22q in glial tumors. Other researchers have briefly reported that glial tumors may also show allelic losses of chromosome 19, suggesting a putative tumor suppressor gene locus on this chromosome (D. T. Ransom et al., Proc. Am. Assoc. Cancer Res., 32:302, 1991). To evaluate whether loss of chromosome 19 alleles is common in glial tumors of different types and grades, we performed Southern blot restriction fragment length polymorphism analysis for multiple chromosome 19 loci in 122 gliomas from 116 patients. Twenty-nine tumors had loss of constitutional heterozygosity of 19q, and four tumors had partial deletions of 19q. Allelic losses on 19q were restricted to grade III anaplastic astrocytomas (4/9) and grade IV glioblastomas (11/46), grade II oligodendrogliomas (2/5) and grade III anaplastic oligodendrogliomas (2/2), and grade II (5/8) and grade III (5/7) mixed oligoastrocytomas. These data demonstrate genetic similarities between astrocytomas, oligodendrogliomas, and mixed glial tumors and indicate the presence of a glial tumor suppressor gene on chromosome 19q.


Asunto(s)
Astrocitoma/genética , Neoplasias Encefálicas/genética , Cromosomas Humanos Par 19 , Genes Supresores de Tumor , Glioma/genética , Oligodendroglioma/genética , Polimorfismo de Longitud del Fragmento de Restricción , Astrocitoma/sangre , Astrocitoma/patología , Neoplasias Encefálicas/sangre , Neoplasias Encefálicas/patología , Deleción Cromosómica , Mapeo Cromosómico , Sondas de ADN , Glioma/sangre , Glioma/patología , Humanos , Oligodendroglioma/sangre , Oligodendroglioma/patología
3.
Cancer Res ; 52(10): 2987-90, 1992 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-1349850

RESUMEN

Loss of genetic material on the short arm of chromosome 17 is observed in approximately 40% of human astrocytomas (WHO grades II and III) and in approximately 30% of cases of glioblastoma multiforme (WHO grade IV). Previous studies of glioblastoma multiforme have shown that the p53 gene, located on the short arm of chromosome 17, is frequently mutated in these glioblastomas. To explore whether lower-grade astrocytomas are also associated with corresponding mutations of the p53 gene, we have investigated a series of 22 human astrocytomas of WHO grades II and III both for loss of heterozygosity on chromosome 17p and for p53 mutations. Mutations in the conserved regions of the p53 gene were identified by single strand conformation polymorphism analysis of exons 5, 6, 7, and 8 and were verified by direct DNA sequencing of the polymerase chain reaction products. p53 mutations were observed in 3 of 8 grade II astrocytomas and 4 of 14 grade II astrocytomas. In all 22 tumors, allelic loss of the short arm of chromosome 17 was investigated by restriction fragment length polymorphism analysis. One-half of the grade II astrocytomas (4 of 8) and grade III astrocytomas (7 of 14) exhibited allelic loss on chromosome 17p. Mutations in the p53 gene were exclusively observed in tumors with allelic loss on 17p. Our results show that p53 mutations are not restricted to glioblastoma multiforme and may be important in the tumorigenesis of lower-grade astrocytomas and that p53 mutations in lower-grade astrocytomas are associated with loss of chromosome 17p. These findings are consistent with a recessive mechanism of action of p53 in WHO grade II and III astrocytoma tumorigenesis.


Asunto(s)
Alelos , Astrocitoma/genética , Deleción Cromosómica , Cromosomas Humanos Par 17/fisiología , Genes p53/genética , Astrocitoma/patología , Secuencia de Bases , Southern Blotting , ADN de Cadena Simple/genética , Exones/genética , Heterocigoto , Humanos , Datos de Secuencia Molecular , Mutación , Conformación de Ácido Nucleico , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción
4.
Cancer Res ; 60(3): 624-35, 2000 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-10676646

RESUMEN

Iododeoxyuridine (IUdR) uptake and retention was imaged by positron emission tomography (PET) at 0-48 min and 24 h after administration of 28.0-64.4 MBq (0.76-1.74 mCi) of [124I]IUdR in 20 patients with brain tumors, including meningiomas and gliomas. The PET images were directly compared with gadolinium contrast-enhanced or T2-weighted magnetic resonance images. Estimates for IUdR-DNA incorporation in tumor tissue (Ki) required pharmacokinetic modeling and fitting of the 0-48 min dynamically acquired data to correct the 24-h image data for residual, nonincorporated radioactivity that did not clear from the tissue during the 24-h period after IUdR injection. Standard uptake values (SUVs) and tumor:brain activity ratios (Tm:Br) were also calculated from the 24-h image data. The Ki, SUV, and Tm/Br values were related to tumor type and grade, tumor labeling index, and survival after the PET scan. The plasma half-life of [124I]IUdR was short (2-3 min), and the arterial plasma input function was similar between patients (48 +/- 12 SUV*min). Plasma clearance of the major radiolabeled metabolite ([124I]iodide) varied somewhat between patients and was markedly prolonged in one patient with renal insufficiency. It was apparent from our analysis that a sizable fraction (15-93%) of residual nonincorporated radioactivity (largely [124I]iodide) remained in the tumors after the 24-h washout period, and this fraction varied between the different tumor groups. Because the SUV and Tm:Br ratio values reflect both IUdR-DNA incorporated and exchangeable nonincorporated radioactivity, any residual nonincorporated radioactivity will amplify their values and distort their significance and interpretation. This was particularly apparent in the meningioma and glioblastoma multiforme groups of tumors. Mean tumor Ki values ranged between 0.5 +/- 0.9 (meningiomas) and 3.9 +/- 2.3 microl/min/g (peak value for glioblastoma multiforme, GBM). Comparable SUV and Tm:Br values at 24 h ranged from 0.13 +/- 0.03 to 0.29 +/- 0.19 and from 2.0 +/- 0.6 to 6.1 +/- 1.5 for meningiomas and peak GBMs, respectively. Thus, the range of values was much greater for Ki (approximately 8-fold) compared with that for SUV (approximately 2.2-fold) and Tm:Br (approximately 3-fold). The expected relationships between Ki, SUV, and Tm:Br and other measures of tumor proliferation (tumor type and grade, labeling index, and patient survival) were observed. However, greater image specificity and significance of the SUV and Tm:Br values would be obtained by achieving greater washout and clearance of the exchangeable fraction of residual (background) radioactivity in the tumors, i.e., by increased hydration and urinary clearance and possibly by imaging later than 24 h after [124I]IUdR administration.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Idoxuridina , Radioisótopos de Yodo , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Neoplasias Encefálicas/patología , División Celular , Femenino , Fluorodesoxiglucosa F18 , Humanos , Riñón/metabolismo , Masculino , Persona de Mediana Edad , Cintigrafía
5.
Clin Cancer Res ; 3(4): 523-30, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9815715

RESUMEN

Mutations of the p53 tumor suppressor gene are a genetic hallmark of human astrocytic neoplasms, but their predictive role in glioma progression is still poorly understood. We analyzed 144 biopsies from 67 patients with recurrent astrocytoma by single-strand conformation polymorphism and direct DNA sequencing. We found that 46 of 67 patients (69%) had a p53 mutation in at least one biopsy. In 41 of these (89%), the mutation was already present in the first biopsy, indicating that p53 mutations are early events in the evolution of diffuse astrocytomas. Double mutations of the p53 gene were observed in three tumors and also present from the first biopsy. Of 28 low-grade astrocytomas with a p53 mutation, 7 (25%) showed loss of the normal allele in the first biopsy. The allele status remained the same in 95% of the cases, irrespective of whether the recurrent lesion had the same or a higher grade of malignancy. Progression of low-grade astrocytomas to anaplastic astrocytoma or glioblastoma occurred at a similar frequency in lesions with (79%) and without (63%) p53 mutations (P = 0.32), indicating that this genetic alteration is associated with tumor recurrence but not predictive of progression to a more malignant phenotype. However, the time interval until progression was shorter in patients with low-grade astrocytomas carrying a p53 mutation (P = 0.055).


Asunto(s)
Astrocitoma/genética , Astrocitoma/patología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Genes p53 , Mutación Puntual , Eliminación de Secuencia , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Sustitución de Aminoácidos , Astrocitoma/cirugía , Biopsia , Neoplasias Encefálicas/cirugía , Niño , Preescolar , Codón , Progresión de la Enfermedad , Exones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Polimorfismo Conformacional Retorcido-Simple , Estudios Retrospectivos , Factores de Tiempo
6.
J Neuropathol Exp Neurol ; 59(6): 544-58, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10850867

RESUMEN

Brain tumors pose a particular challenge to molecular oncology. Many different tumor entities develop in the nervous system and some of them appear to follow distinct pathogenic routes. Molecular genetic alterations have increasingly been reported in nervous system neoplasms. However, a considerable number of affected genes remain to be identified. We present here a comprehensive allelotype analysis of 466 nervous system tumors based on loss of heterozygosity (LOH) studies with 129 microsatellite markers that span the genome. Specific alterations of the EGFR, CDK4, CDKN2A, TP53, DMBT1, NF2, and PTEN genes were analyzed in addition. Our data point to several novel genetic loci associated with brain tumor development, demonstrate relationships between molecular changes and histopathological features, and further expand the concept of molecular tumor variants in neuro-oncology. This catalogue may provide a valuable framework for future studies to delineate molecular pathways in many types of human central nervous system tumors.


Asunto(s)
Alelos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patología , Humanos , Pérdida de Heterocigocidad , Repeticiones de Microsatélite , Biología Molecular/métodos , Mutación/genética , Análisis de Supervivencia
7.
Brain Pathol ; 5(1): 15-23, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7767487

RESUMEN

This report describes clinical, neuropathological and molecular genetic findings in a Swiss family with four brain tumours in only two generations. The neoplasms observed covered a wide range of biologic behaviour, from a slowly growing lesion already apparent at birth, to anaplastic astrocytoma in a young adult and glioblastomas at the age of less than 10 years. The only non-neural neoplasms in this family were a case of leukemia and an adrenocortical carcinoma. A germline deletion of codon 236 of the p53 tumour suppressor gene was identified as an underlying cause and detected in all affected family members. This mutation has not previously been reported as germline transmission or in sporadic tumours. The unusual accumulation of CNS tumours may be due to a certain organ-specific effect of this particular p53 mutation or it may reflect the specific genetic back-ground of this family.


Asunto(s)
Neoplasias Encefálicas/genética , Genes p53 , Mutación de Línea Germinal , Eliminación de Secuencia , Adulto , Anciano , Secuencia de Bases , Neoplasias Encefálicas/patología , Niño , Preescolar , Codón , Femenino , Humanos , Inmunohistoquímica , Masculino , Datos de Secuencia Molecular , Linaje , Reacción en Cadena de la Polimerasa
8.
Brain Pathol ; 3(3): 297-306, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8293189

RESUMEN

The central neurocytoma is a supratentorial, often calcified brain tumour affecting young adults and is typically located in the lateral ventricles in the region of the foramen of Monro. Clinically, the tumour causes signs of increased intracranial pressure, visual and mental disturbances and, occasionally, pyramidal or endocrine symptoms. By light microscopy, the tumour is composed of small round cells in a delicate fibrillary matrix. Tumour cells consistently show features of neuronal differentiation by electron microscopy (synapses, dense-core vesicles, presynaptic clear vesicles, specialized synaptic junctions) and immunoreactivity for synaptophysin and other neuronal marker proteins. The tumour can be totally removed in nearly half of the cases. After incomplete surgical resection neurocytomas may recur but because of their low proliferation potential, radio- or chemotherapy are not generally recommended. Postoperative recurrence-free survival times of up to 19 years have been reported. Neurocytomas constitute nearly one half of supratentorial intraventricular tumours in adults but amount to less than 1% of all tumours of the central nervous system and its coverings.


Asunto(s)
Neoplasias Encefálicas/patología , Neurocitoma/patología , Neoplasias Encefálicas/fisiopatología , Femenino , Humanos , Masculino , Neurocitoma/fisiopatología
9.
Brain Pathol ; 3(1): 19-26, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8269081

RESUMEN

Glioblastoma multiforme is a clinically and histologically heterogeneous lesion; however, to date, it has not been possible to subdivide glioblastomas on a clinical, histopathological or biological basis. Previous studies have demonstrated that loss of portions of chromosomes 10 and 17 and amplification of the epidermal growth factor receptor (EGFR) gene are the most frequent genetic alterations in glioblastoma. We therefore examined 74 glioblastomas from 67 patients for loss of heterozygosity on chromosomes 10 and 17, and for amplification of the epidermal growth factor receptor gene, to determine whether glioblastomas can be subtyped on a genetic basis. Using Southern blot analysis we were able to detect different patterns of genomic alterations. Eighteen of 67 informative patients were characterized by a loss of heterozygosity on the short arm of chromosome 17 in the tumor tissue. Forty-five of 64 informative patients showed a loss of heterozygosity on chromosome 10. Amplification of the epidermal growth factor receptor gene was noted in 25 of 67 patients and was restricted to those glioblastomas that had lost portions of chromosome 10. Epidermal growth factor receptor gene amplification occurred significantly more often in patients without chromosome 17p loss than in patients with chromosome 17p loss (p = 0.01). In addition, those glioblastomas with a loss of chromosome 17p occurred in patients significantly younger than those with glioblastomas characterized by EGFR gene amplification (p = 0.001). These data emphasize the genetic heterogeneity of glioblastoma and suggest the division of glioblastoma into genetic subsets.


Asunto(s)
Cromosomas Humanos Par 10 , Cromosomas Humanos Par 17 , Receptores ErbB/genética , Glioblastoma/genética , Adolescente , Adulto , Anciano , Southern Blotting , Femenino , Amplificación de Genes , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad
10.
J Nucl Med ; 39(5): 879-84, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9591593

RESUMEN

UNLABELLED: Dexamethasone (DEX) is frequently used in brain tumor management. This study investigated the effect of DEX treatment and plasma glucose levels on 18F-fluorodeoxyglucose (FDG) uptake in patients with malignant gliomas (16 glioblastoma, 3 anaplastic astrocytoma). METHODS: Fifteen DEX-treated patients (mean relative dose 0.23 +/- 0.15 mg(-1) x kg(-1) x day(-1), range 0.07-0.53), four patients not treated with DEX and nine healthy subjects were studied using PET and FDG. PET data obtained from tumors and the contralateral cortex were fitted to a standard two-tissue compartment model. The FDG transport and phosphorylation rates, distribution volume (DV), steady-state accumulation (Ki), deoxyglucose metabolism (R), plasma volume as well as standardized uptake values (SUVs) and tumor-to-brain ratios were determined. In addition, the tumor size was estimated from the maximal area of contrast-enhancing tumor on computed cranial tomography (CCT) scans or MRI. RESULTS: FDG uptake was depressed in the contralateral cortex of patients and was related to tumor size. With increasing relative DEX dose, a decrease in the DV of tumors (linear regression p = 0.021) and in the DV (p = 0.109) and plasma volume (p = 0.010) of contralateral cortex was found. R, Ki and SUVs in tumors and contralateral cortex were not related to the relative DEX dose. With increasing plasma glucose levels, differential decreases in Ki and SUVs in tumors (p = 0.057 and p = 0.733, respectively) and contralateral cortex (p = 0.001 and p = 0.029, respectively) were observed. CONCLUSION: The data suggest that DEX affects FDG uptake in malignant gliomas through interaction with cerebral blood vessels and extracellular space, whereas FDG metabolism in tumors is not influenced substantially. This is of practical importance for patients having serial brain tumor imaging for treatment evaluation because patients may receive different DEX doses at different time points in the course of their disease. By contrast, the plasma glucose level must be considered a confounding variable when SUVs, tumor-to-brain ratios or Ki are used for treatment evaluation.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Glucemia/metabolismo , Dexametasona/uso terapéutico , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Glioblastoma/diagnóstico por imagen , Radiofármacos , Neoplasias Supratentoriales/diagnóstico por imagen , Tomografía Computarizada de Emisión , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Radioisótopos de Flúor/farmacocinética , Fluorodesoxiglucosa F18/farmacocinética , Glioblastoma/tratamiento farmacológico , Glioblastoma/metabolismo , Humanos , Persona de Mediana Edad , Radiofármacos/farmacocinética , Estudios Retrospectivos , Neoplasias Supratentoriales/tratamiento farmacológico , Neoplasias Supratentoriales/metabolismo
11.
Virchows Arch ; 427(2): 113-8, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7582239

RESUMEN

Diffusely infiltrating low-grade astrocytomas (WHO grade II) have an intrinsic tendency for progression to anaplastic astrocytoma (WHO grade III) and glioblastoma (WHO grade IV). This change is due to the sequential acquisition of genetic alterations, several of which have recently been identified. In low-grade astrocytomas, p53 mutations with or without loss of heterozygosity on chromosome 17p are the principal detectable change. Anaplastic astrocytomas contain p53 mutations at an overall incidence of 34% and, in addition, loss of heterozygosity on chromosome 19q and frequent homozygous deletion of the p16 tumor suppressor (MTS-1) gene. The most malignant astrocytic neoplasms, the glioblastoma, further shows loss of chromosome 10 and amplification of the epidermal growth factor receptor (EGF-R) gene at overall incidences of 66% and 34%, respectively. The type and distribution of p53 mutations in astrocytic brain tumours are not suggestive of specific environmental carcinogens operative in their aetiology. Analysis of 91 families with p53 germline mutations reported to date show that tumours of the nervous system account to 12% of all neoplasms. Of a total of 57 brain tumours reported, 30 were classified histologically and of these, 73% were of astrocytic origin. The observation that somatic p53 mutations in sporadic brain tumours are largely restricted to those of astrocytic origin and that astrocytomas also prevail among CNS neoplasms associated with p53 germline mutation strongly suggests, that p53 mutations are capable of initiating neoplastic transformation in astrocytes of the human nervous system.


Asunto(s)
Astrocitoma/genética , Neoplasias Encefálicas/genética , Genes p53/genética , Mutación/genética , Adulto , Astrocitoma/patología , Neoplasias Encefálicas/patología , Niño , Progresión de la Enfermedad , Glioblastoma/genética , Glioblastoma/patología , Humanos
12.
AJNR Am J Neuroradiol ; 18(5): 939-44, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9159374

RESUMEN

PURPOSE: To evaluate the magnetic characteristics, artifact formation, and implant safety of titanium aneurysm clips for use in MR imaging. METHODS: Aneurysm clips made of titanium alloy TiAl6V4 were tested in a magnetometer to determine their magnetic susceptibility and in a 1.5-T MR imager using both a geometric phantom and an animal model. A commercially available alpha-Phynox clip served as the reference standard. RESULTS: We found minimal magnetization and a significant reduction in image artifacts with the titanium clip as compared with the Phynox clip. CONCLUSION: The titanium clips improve image quality, biocompatibility, and patient safety in medical MR applications.


Asunto(s)
Aneurisma/cirugía , Artefactos , Angiografía por Resonancia Magnética/instrumentación , Instrumentos Quirúrgicos , Titanio , Aneurisma/diagnóstico , Animales , Materiales Biocompatibles , Modelos Animales de Enfermedad , Seguridad de Equipos , Neurocirugia/instrumentación , Neurocirugia/métodos , Fantasmas de Imagen , Ratas
13.
J Neurol Sci ; 132(1): 20-7, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8523026

RESUMEN

The influence of the blood-brain barrier (BBB) on tracer uptake was investigated in 21 patients with gliomas and meningiomas using PET, [18F]fluorodeoxyglucose (FDG), [18C]methionine (MET) and the K+ analog rubidium-82 (RUB) whose uptake into brain is largely prevented if the BBB is intact. Tracer uptake was quantitated by (1) multiple time graphical plotting providing tracer distribution volume (VD), unidirectional tracer uptake (Ki), and (2) normalized uptake (NU) which is a measure of net tissue radioactivity related to administered activity and body weight. VD, Ki and NU of MET were higher in meningiomas compared to gliomas and were significantly correlated with NU RUB (Spearman rank: p < 0.005 (VD), p < 0.05 (Ki), p < 0.001 (NU)). NU MET correlated with VD (p < 0.001) and Ki (p < 0.005) of MET. For FDG, tumor VD was in the range of contralateral cortex. Ki and NU values of FDG were highest in glioblastomas. NU of FDG correlated significantly with Ki of FDG (p < 0.005) but not with VD. The results suggest, that alteration of MET uptake in tumors is governed by changes of tracer influx across the BBB, whereas FDG uptake is related to tracer metabolism. This makes FDG the appropriate tracer particularly for the differential diagnosis of contrast enhancing lesions in operated and irradiated patients.


Asunto(s)
Barrera Hematoencefálica/fisiología , Neoplasias Encefálicas/fisiopatología , Desoxiglucosa/análogos & derivados , Metionina/metabolismo , Adulto , Anciano , Neoplasias Encefálicas/diagnóstico por imagen , Radioisótopos de Carbono , Desoxiglucosa/metabolismo , Femenino , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Radioisótopos de Rubidio , Tomografía Computarizada de Emisión , Tomografía Computarizada por Rayos X
14.
J Neurol Sci ; 156(1): 73-7, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9559990

RESUMEN

Cerebral gliomas may cause a reduction of glucose metabolism in the cerebellum contralateral to the tumor side (crossed cerebellar diaschisis, CCD). We investigated whether CCD is related to tumor localization, histological grade, size and tumor biochemistry. Cerebellar glucose metabolism was measured in 44 glioma patients and 15 healthy subjects using positron emission tomography and [18F]fluorodeoxyglucose (FDG). CCD was determined by calculating an asymmetry index of cerebellar glucose metabolism. Further, the tumor uptake of FDG and [11C]methionine (MET) was also assessed, and was expressed as ratio of normalized tracer uptake in tumor over contralateral cortex (T/C). Frontal lobe tumors were associated with highest CCD values. For these tumors, CCD was higher in malignant (-11.8+/-9.9%) than in low-grade (-4.3+/-4.1%) gliomas (P=0.010). In addition, frontal lobe tumors showed increasing CCD values with increasing size. In tumors of the parietal or temporal lobe, CCD was less marked or absent. T/C ratios of tumor tracer uptake were higher in malignant than in low-grade gliomas, but were not correlated with CCD. Our data indicate that the magnitude of CCD is mainly determined by tumor localization and size, the latter being associated with tumor grade. These findings raise the question whether CCD provides a measure of expansion or progression particularly in low-grade tumors of the frontal lobe.


Asunto(s)
Neoplasias Encefálicas/fisiopatología , Cerebelo/fisiopatología , Glioma/fisiopatología , Tomografía Computarizada de Emisión , Adulto , Animales , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/metabolismo , Cerebelo/diagnóstico por imagen , Cerebelo/metabolismo , Fluorodesoxiglucosa F18 , Glioma/diagnóstico por imagen , Glioma/metabolismo , Glucosa/metabolismo , Humanos , Metionina , Persona de Mediana Edad , Radiofármacos , Estudios Retrospectivos
15.
Neurosurgery ; 28(5): 646-50; discussion 650-1, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1876241

RESUMEN

Seventy of 178 patients with acoustic tumors initially were treated conservatively and have been followed up for an average of 26 +/- 2 months. The tumor size was determined by the mean maximum anteroposterior and mediolateral diameters, using computed tomographic or magnetic resonance imaging scans obtained sequentially throughout the follow-up period. The average tumor growth was 1.6 +/- 0.4 mm the 1st year, and 1.9 +/- 1.0 mm the 2nd year (range, -2 to 17 mm/y): 4 tumors showed apparent regression, 28 (40%) had no detectable growth, and 37 (53%) exhibited growth (average, 3.8 +/- 1.2 mm/y). Within individual patients, the tumor growth rate determined during the 1st year of follow-up was predictive of tumor growth rate determined during the following year. Rapid tumor growth or clinical deterioration in 9 of the 70 patients (13%) who initially were treated conservatively necessitated subsequent surgery an average of 14 +/- 5 months after the patient was initially seen. This group had a larger initial tumor size (27.0 +/- 3.4 mm vs. 21.3 +/- 0.9 mm, P less than 0.05), and a faster 1-year growth rate (7.9 +/- 2.3 mm/y vs. 1.3 +/- 0.3 mm/y, P less than 0.05) than the 61 patients who did not require surgery. Two patients, however, experienced neurological deterioration that required surgery, even though there was no tumor growth. The high incidence of acoustic tumors with no detectable growth or apparent spontaneous regression must be taken into account when evaluating the indications for surgery and the efficacy of radiotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Neuroma Acústico/terapia , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuroma Acústico/diagnóstico , Neuroma Acústico/cirugía , Estudios Retrospectivos , Factores de Tiempo , Tomografía Computarizada por Rayos X
16.
J Neurosurg ; 76(1): 32-7, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1727166

RESUMEN

The central neurocytoma has recently been added to the differential diagnosis of intraventricular tumors. Histopathologically, this tumor is characterized by a uniform neoplastic cell population with features of neuronal differentiation. Central neurocytomas occur in young adults, develop in the area of the foramen of Monro, and are usually associated with the septum pellucidum. Initial reports appeared to indicate that these tumors are benign lesions with a favorable postoperative prognosis. The authors present clinical and neuropathological findings in a series of eight patients with central neurocytoma. An anterior transcallosal microneurosurgical approach yielded good outcomes. Postoperative radiation therapy was restricted to two patients with a malignant variant of central neurocytoma and one patient with a recurrent tumor. Observations of anaplastic variants of this neoplasm in two cases and local tumor recurrences in three indicate that the biological behavior and postoperative prognosis of central neurocytoma may not always be as favorable as previously assumed.


Asunto(s)
Neoplasias del Ventrículo Cerebral/patología , Neoplasias del Ventrículo Cerebral/cirugía , Neuroblastoma/patología , Neuroblastoma/cirugía , Adulto , Neoplasias del Ventrículo Cerebral/diagnóstico , Terapia Combinada , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Neuroblastoma/diagnóstico , Pronóstico , Tomografía Computarizada por Rayos X
17.
J Neurosurg ; 77(2): 295-301, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1320666

RESUMEN

Although the loss of tumor suppressor genes and the activation of oncogenes have been established as two of the fundamental mechanisms of tumorigenesis in human cancer, little is known about the possible interactions between these two mechanisms. Loss of genetic material on chromosome 10 and amplification of the epidermal growth factor receptor (EGFR) gene are the most frequently reported genetic abnormalities in glioblastoma multiforme. In order to examine a possible correlation between these two genetic aberrations, the authors studied 106 gliomas (58 glioblastomas, 14 anaplastic astrocytomas, five astrocytomas, nine pilocytic astrocytomas, seven mixed gliomas, six oligodendrogliomas, two ependymomas, one subependymoma, one subependymal giant-cell astrocytoma, and three gangliogliomas) with Southern blot analysis for loss of heterozygosity on both arms of chromosome 10 and for amplification of the EGFR gene. Both the loss of genetic material on chromosome 10 and EGFR gene amplification were restricted to the glioblastomas. Of the 58 glioblastoma patients, 72% showed loss of chromosome 10 and 38% showed EGFR gene amplification. The remaining 28% had neither loss of chromosome 10 nor EGFR gene amplification. Without exception, the glioblastomas that exhibited EGFR gene amplification had also lost genetic material on chromosome 10 (p less than 0.001). This invariable association suggests a relationship between the two genetic events. Moreover, the presence of 15 cases of glioblastoma with loss of chromosome 10 but without EGFR gene amplification may further imply that the loss of a tumor suppressor gene (or genes) on chromosome 10 precedes EGFR gene amplification in glioblastoma tumorigenesis.


Asunto(s)
Neoplasias Encefálicas/genética , Cromosomas Humanos Par 10 , Receptores ErbB/genética , Amplificación de Genes , Glioblastoma/genética , Biomarcadores de Tumor/genética , ADN de Neoplasias/genética , Genes Supresores de Tumor , Humanos
20.
Homeopathy ; 96(1): 35-41, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17227746

RESUMEN

BACKGROUND: Treatment of patients with attention deficit hyperactivity disorder (ADHD) with homeopathy is difficult. The Swiss randomised, placebo controlled, cross-over trial in ADHD patients (Swiss ADHD trial) was designed with an open-label screening phase prior to the randomised controlled phase. During the screening phase, the response of each child to successive homeopathic medications was observed until the optimal medication was identified. Only children who reached a predefined level of improvement participated in the randomised, cross-over phase. Although the randomised phase revealed a significant beneficial effect of homeopathy, the cross-over caused a strong carryover effect diminishing the apparent difference between placebo and verum treatment. METHODS: This retrospective analysis explores the screening phase data with respect to the risk of failure to demonstrate a specific effect of a randomised controlled trial (RCT) with randomisation at the start of the treatment. RESULTS: During the screening phase, 84% (70/83) of the children responded to treatment and reached eligibility for the randomised trial after a median time of 5 months (range 1-18), with a median of 3 different medications (range 1-9). Thirteen children (16%) did not reach eligibility. Five months after treatment start, the difference in Conners Global Index (CGI) rating between responders and non-responders became highly significant (p = 0.0006). Improvement in CGI was much greater following the identification of the optimal medication than in the preceding suboptimal treatment period (p < 0.0001). CONCLUSIONS: Because of the necessity of identifying an optimal medication before response to treatment can be expected, randomisation at the start of treatment in an RCT of homeopathy in ADHD children has a high risk of failure to demonstrate a specific treatment effect, if the observation time is shorter than 12 months.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Homeopatía/métodos , Materia Medica/uso terapéutico , Selección de Paciente , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Niño , Estudios Cruzados , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Análisis Multivariante , Proyectos de Investigación , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Suiza , Resultado del Tratamiento
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