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Jiménez Isabel Carabia Júlia Bobillo Sabela Palacio Carles Abrisqueta Pau Pagès Carlota Nieto Juan C. Castellví Josep Martínez-Ricarte Francisco Escoda Lourdes Perla Cristóbal Céspedes Torrez Dennis H. Boix Joan Purroy Noelia Puigdefàbregas Lluís Seoane Joan Bosch Francesc Crespo Marta 《Journal of neuro-oncology》2020,149(1):13-25
Journal of Neuro-Oncology - Patients diagnosed with primary central nervous system lymphoma (PCNSL) often face dismal outcomes due to the limited availability of therapeutic options. PCNSL cells... 相似文献
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M. I. Manrique-Poyato A. J. Muñoz-Pajares V. Loreto M. D. López-León J. Cabrero J. P. M. Camacho 《Chromosome research》2006,14(6):693-700
We have analysed B chromosome frequency for three consecutive years, B transmission rate at population and individual levels,
clutch size, egg fertility and embryo–adult viability in a natural population of the grasshopper Eyprepocnemis plorans containing two different B chromosome variants, i.e. B2 and B24, the second being derived from the first and having replaced it in nearby populations. From 2002 to 2003 the relative frequency
of both variants changed, although the differences did not reach significance. A mother–offspring analysis showed no significant
effect of any of the two B variants on clutch size, egg fertility or embryo–adult viability, but B24 was more efficiently transmitted than B2 through males from the 2002 season, which explains the observed frequency change. Controlled crosses, at individual level,
showed significant drive through some females for B24 but not for B2, suggesting that this difference in transmission rate might also be important for the substitution process. The analysis
of relative fitness for B2 and B24 carriers for all fitness components, as a whole, showed a significantly better performance of B24-carrying individuals, suggesting that the cumulative effect of these slight differences might contribute to the replacement
of B2 by B24.
Electronic Supplementary Material Supplementary material is available for this article at . 相似文献
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M. E. Locatto V. Di Loreto M. C. Fernández D. Caferra R. C. Puche 《Acta diabetologica》1997,34(3):211-216
This report deals with the relationships between glucose (G) and insulin on the tubular transport of phosphate (P) in chronically
diabetic rats with high plasma levels of parathyroid hormone (PTH). Alloxan-induced diabetes leads to phosphorus depletion
of the soft tissues. This phenomenon appears associated with weight loss and negative P balances caused by the increased urinary
P excretion. Administration of 2 IU of insulin/100 g body weight (bw) to diabetic rats normalized their P balance and body
weight. The effect of parathyroid function on the P metabolism of diabetic rats was investigated with balance experiments.
Diabetic rats, intact or thyroparathyroidectomized (TPTX), have a greater urinary excretion of P than their controls. However,
in control rats, the ratio intact:TPTX for urinary P is 1.0:0.76, showing the antiphosphaturic effect of parathyroid ablation.
For diabetic animals, on the other hand, the ratio is 1.0:1.44. The simultaneous deficit of insulin and PTH thus quadruples
the urinary P loss, instead of compensating for each other. The contribution of insulin deficit and hyperglycemia to the defect
in tubular reabsorption (TRP) was investigated with clearance experiments (done on anesthetized, perfused rats). Five experimental
groups were used: Controls (C), diabetics (D), controls+glucose (C+G), diabetics+insulin (D+I) and diabetics+insulin+glucose
(D+I+G). All experimental groups showed a linear relationship between the TRP of P and G. The regression equation for C is
significantly different (F=40.1, P<0.001) from that of D animals. The slope value measure the number of μmoles of P per μmol of G reabsorbed. For C and D rats,
the ratio P:G approximates 1:4 and 1:20, respectively. The increase in P:G ratios represents the competition between both
substrates for tubular resorption. Glycemias up to 11 mM (C and D+I) exist concurrent with the P:G ratio 1:4. Glycemias above
25 mM (D, C+G and D+I+G) produce a P:G ratio of 1:20. Fractional excretion of P (FEP) increased significantly in untreated,
chronically diabetic rats (0.47± 0.12 vs controls=0.05±0.01, P<0.001). After a single intramuscular injection of insulin, the FEP decreased as a function of insulin levels. To normalize
the FEP of diabetic rats in short-term experiments, insulin had to be administered in doses that produce plasma insulin levels
25 times greater than normal. The general information afforded by the present experiments shows that in untreated, chronically
diabetic rats, insulin deficit plays an indirect role. The absence of PTH enhances the effect of hyperglycemia. The latter
and the concurrent tubular overload of glucose are the cause of hyperphosphaturia in these animals.
Received: 10 September 1996 / Accepted in revised form: 18 April 1997 相似文献
7.
Di Loreto S. Florio T. Scarnati E. 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,89(1):79-86
Summary Extracellular single-neuron recordings were obtained from electrophysiologically identified nigrostriatal neurons in chloral hydrate anesthetized rats, in order to test the hypothesis that excitatory amino acid receptors are involved in responses of these neurons to electrical stimulation of the pontine region where the pedunculopontine nucleus (PPN) is located. The effects of iontophoretic application of excitatory amino acids and their antagonists as well as of cholinergic antagonists were tested on the fast orthodromic excitation of nigrostriatal neurons evoked by stimulation of the PPN region. The N-methyl-D-aspartate (NMDA) receptor antagonist D-a-aminoadipic acid as well as the cholinergic receptor antagonists mecamylamine and atropine failed to suppress the synaptic excitation of nigral neurons. The NMDA receptor antagonist DL-2-amino-5-phosphonovalerate exerted a weak depressant action on the synaptic response in a few neurons only. On the contrary, the broad spectrum antagonists of excitatory amino acid receptors kynurenic acid and gamma-Dglutamyl-amino-methyl-sulphonate were found to block simultaneously both the synaptic excitation and the neuronal responses to iontophoretic pulses of glutamate while leaving unaffected the neuronal responses to local application of acetylcholine or carbachol. The competitive antagonist of non-NMDA receptors 6-cyano-2,3-dihy-droxy-7-nitro-quinoxaline suppressed the synaptic excitation at ejection currents which antagonized neuronal responses to quisqualate and kainate. These results suggest that PPN excitatory fibers synapsing onto pars compacta nigrostriatal neurons utilize an excitatory amino acid as a synaptic transmitter acting preferentially on non-NMDA receptors. 相似文献
8.
A case of primary low grade B cell lymphoma of the salivary gland associated with a low grade B cell lymphoma of the thymus and involvement of the skin is reported. The lesions in the salivary gland and in the thymus showed the typical features of a lymphoma arising from the mucosa associated lymphoid tissue (MALT) and comprised lymphatic follicles, centrocyte-like (CCL) cells and lymphoepithelial lesions. Immunohistochemistry and Southern blot analysis supported the hypothesis that these lesions can originate from the same cellular clone. These findings confirm the occurrence of low grade B cell MALT lymphoma in the thymus and the possibility of spread of MALT lymphoma to other mucosal sites. 相似文献
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A. Llombart-Bosch C. Carda A. Peydro-Olaya R. Noguera J. Boix A. Pellin 《Virchows Archiv : an international journal of pathology》1989,414(3):199-208
Summary Esthesioneuroblastoma (ESTH) is a neuroepithelial-cell-derived neoplasm of the olfactory mucosa composed of homogeneous small round cells which contain neurosecretory granules. Melanin has been detected in such tumours only occasionally. Here we describe a new case of ESTH with divergent differentiation. The primary neoplasm was found in a 67 year-old female, involving the left nasal and maxillary sinus; she died of cerebral metastasis ten months after diagnosis. Histologically only small round cells were seen, with S-100 and NSE positivity. Electron microscopy revealed neurosecretory granules and filaments, as well as the occasional presence of melanosomes. A nude mice xenograft line has been established, and is presently in its ninth transfer. Two cell types are present: small round-to-spindle shaped cells with neural features, and large epithelial-like ones. Both immunohistochemistry and electron microscopy confirm this dual differentiation, with the presence of membrane-bound dense-core neural secretion, as well as melanosomes of neuroectodermal origin. Additionally, an in vitro cell line has been established. Cytogenetic analysis confirmed the presence of both malignant human melanoma patterns; non-random abnormalities in chromosomes 1 and 6, extra copies of chromosome 7. Duplication of the long arm of chromosome 14, as seen in olfactory neuroblastoma, is also seen.This work has been supported, in part, with a grant (83/058) from the US-Spain Joint Committee for Scientific and Technological Cooperation (Madrid). This paper was presented, in abbreviated form, at the 72nd Tagung of the Deutsche Gesellschaft für Pathologie, Hannover (24–28 May, 1988) 相似文献