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991.
Essential thrombocythemia (ET) is rare in children, and little or no information is available about clonality or JAK2 mutations. However, the analyses in this work prove useful for the diagnosis of adult myeloproliferative disorders (MPDs). We evaluated the clonality status and V617FJAK2 mutation in 20 children affected by ET and compared them with 47 consecutive adult ET cases. Clonality was evaluated on the DNA of granulocytes and on the RNA of platelets. V617FJAK2 was analyzed by sequencing tests, allele-specific polymerase chain reaction (PCR), and digestion by BsaXI. A monoclonal pattern was found in 4 (28.5%) of 14 children and in 45% of informative adults. Heterozygous V617FJAK2 was found less frequently in children than in adults (P < .009). Only 2 girls showed both the V617FJAK2 mutation and a monoclonal pattern; one of them was the only child presenting a major thrombotic complication. In contrast to adults, most children with ET do not show either a clonal disorder or the V617FJAK2 mutation.  相似文献   
992.
993.
Diffusion tensor imaging (DTI) tractography enables the in vivo visualization of the course of white matter tracts inside or around a tumor, and it provides the surgeon with important information in resection planning. This study is aimed at assessing the ability of preoperative DTI tractography in predicting the extent of the resection achievable in surgical removal of gliomas. Patients with low-grade gliomas (LGGs; 46) and high-grade gliomas (HGGs; 27) were studied using a 3T scanner according to a protocol including a morphological study (T2, fluid-attenuated inversion-recovery, T1 sequences) and DTI acquisitions (b = 1000 s/mm(2), 32 gradient directions). Preoperative tractography was performed off-line on the basis of a streamline algorithm, by reconstructing the inferior fronto-occipital (IFO), the superior longitudinal fascicle (SLF), and the corticospinal tract (CST). For each patient, the relationship between each bundle reconstructed and the lesion was analyzed. Initial and residual tumor volumes were measured on preoperative and postoperative 3D fluid-attenuated inversion-recovery images for LGGs and postcontrast T1-weighted scans for HGGs. The presence of intact fascicles was predictive of a better surgical outcome, because these cases showed a higher probability of total resection than did subtotal and partial resection. The presence of infiltrated or displaced CST or infiltrated IFO was predictive of a lower probability of total resection, especially for tumors with preoperative volume <100 cm(3). DTI tractography can thus be considered to be a promising tool for estimating preoperatively the degree of radicality to be reached by surgical resection. This information will aid clinicians in identifying patients who will mostly benefit from surgery.  相似文献   
994.
Essential thrombocythemia (ET) may occur in women of childbearing age. To investigate the risk of pregnancy complications, we studied 103 pregnancies that occurred in 62 women with ET. The 2-tailed Fisher exact test showed that pregnancy outcome was independent from that of a previous pregnancy. The rate of live birth was 64%, and 51% of pregnancies were uneventful. Maternal complications occurred in 9%, while fetal complications occurred in 40% of pregnancies. The Mantel-Haenszel method showed that fetal loss in women with ET was 3.4-fold higher (95% confidence interval [CI]: 3-3.9; P < .001) than in the general population. Half of the women studied carried the JAK2 (617V>F) mutation, and a multivariate logistic regression model identified this mutation as an independent predictor of pregnancy complications (P = .01). Neither the platelet count nor the leukocyte count was a risk factor. JAK2 (617V>F)-positive patients had an odds ratio of 2.02 (95% CI: 1.1 - 3.8) of developing complications in comparison with JAK2 (617V>F)-negative patients. Aspirin did not prevent complication in JAK2 (617V>F)-positive patients and appeared to worsen outcome in JAK2 (617V>F)-negative patients. A relationship was found between JAK2 (617V>F) and fetal loss (P = .05). This study indicates that patients carrying the JAK2 (617V>F) mutation have higher risk of developing pregnancy complications.  相似文献   
995.
Microvessel density (MVD) is considered to be a prognostic marker in many tumours. Nevertheless, conflicting results were achieved regarding its prognostic role in meningiomas when it was quantified through pan-endothelial markers such as CD34, CD31 or Factor VIII. In the present study, MVD was assessed in meningiomas through the specific marker for neo-angiogenesis CD105. Fifty-four formalin fixed, paraffin embedded, surgical cases of meningiomas (WHO 28 grade I and 26 grade II) as well as ten normal leptomeningeal samples were submitted to immunohistochemical analysis for CD105. CD34 immuno-expression was also evaluated on consecutive parallel sections. For each case, MVD was estimated in terms of number of vessels/mm2. CD105 was not evidenced in normal samples, whereas it was demonstrated in the vessels within 14/28 WHO grade I cases and within 24/26 WHO grade II meningiomas. On the contrary, CD34 antibody stained blood vessels in both normal and neoplastic samples; moreover, in each case, it stained more microvessels than CD105 antibody (25.33 ± 21.16 vs. 50.72 ± 26.75). Higher CD105 counts were significantly correlated with higher histological grade and Ki-67 LI > 4%. No statistical significant correlations were encountered between MVD measured by either CD105 and CD34 and sex, age, site of tumour or extent of surgical resection. CD105-MVD, but not CD34-MVD, showed an inverse significant correlation with overall survival and recurrence-free survival. In conclusion, our study suggests the higher specificity of CD105 in comparison to pan-endothelial markers in the evaluation of meningioma neo-angiogenesis, and its higher prognostic significance. CD105 might serve as a target for therapeutic approaches blocking blood supply in meningiomas.  相似文献   
996.
Therapeutic decision-making in primary myelofibrosis (PMF) is becoming more challenging because of the increasing use of allogeneic stem cell transplantation and new investigational drugs. To enhance this process by developing a highly discriminative prognostic system, 1054 patients consecutively diagnosed with PMF at 7 centers were studied. Overall median survival was 69 months (95% confidence interval [CI]: 61-76). Multivariate analysis of parameters obtained at disease diagnosis identified age greater than 65 years, presence of constitutional symptoms, hemoglobin level less than 10 g/dL, leukocyte count greater than 25 x 10(9)/L, and circulating blast cells 1% or greater as predictors of shortened survival. Based on the presence of 0 (low risk), 1 (intermediate risk-1), 2 (intermediate risk-2) or greater than or equal to 3 (high risk) of these variables, 4 risk groups with no overlapping in their survival curves were delineated; respective median survivals were 135, 95, 48, and 27 months (P< .001). Compared with prior prognostic models, the new risk stratification system displayed higher predictive accuracy, replicability, and discriminating power. In 409 patients with assessable metaphases, cytogenetic abnormalities were associated with shorter survival, but their independent contribution to prognosis was restricted to patients in the intermediate-risk groups. JAK2V617F did not cluster with a specific risk group or affect survival.  相似文献   
997.
Cyproheptadine, an inhibitor of the H1 histamine receptors, has recently shown activity in models of leukaemia and myeloma, presumably through inhibition of cyclin-D expression. Mantle cell lymphoma (MCL) is an aggressive subtype of non-Hodgkin lymphoma characterized by overexpression of cyclin-D1. We investigated the effect of cyproheptadine alone and in combination with the proteasome inhibitor bortezomib in models of MCL. The combination of these drugs was mathematically synergistic, producing significant reductions in the mitochondrial membrane potential leading to apoptosis. In a severe combined immunodeficient beige mouse model, cyproheptadine plus bortezomib demonstrated a statistically significant advantage compared to either agent alone.  相似文献   
998.
Forty-two infants (20 males, 22 females) with classical phenylketonuria (PKU) entered a prospective, double-blind, randomized study to investigate the effects on biochemical and physiological outcomes of a phenylalanine-free infant formula containing a fat blend supplemented with the long-chain polyunsaturated fatty acids (LC-PUFA), docosahexaenoic acid (DHA, C22:6 n-3), and arachidonic acid (AA, C20:4 n-6). Between entry and 20 weeks (entry and 1y) of age, median DHA levels in erythrocyte membrane phospholipids decreased by 15% (22%) in the LC-PUFA supplemented group (n=21) and by 61% (64%) in the control group (p<0.001; n=18). A dietary supply of LC-PUFA in infants with PKU prevents the decline in DHA levels associated with a diet supplying minimal sources of LC-PUFA. DHA status in turn, independent of diet, may influence the maturation of the visual system in infants with PKU.  相似文献   
999.
1000.
In a previous study we showed that healthy highly hypnotizable subjects, during the suggestion of a moderately unpleasant situation administered in awake conditions, exhibited a sympathetic response greatly attenuated with respect to non-hypnotizable individuals. This was interpreted as a natural protection of hypnotizable subjects against the cardiovascular effects of cognitive stress. Aim of the present study was to investigate whether the hypnotic trait is able to modulate the autonomic and cerebral activities also in specific phobic awake hypnotizable (Highs) and non-hypnotizable (Lows) subjects. Electroencephalogram, electrooculogram, electromiogram of corrugator muscle, electrocardiogram, respirogram and tonic electrodermal activity were recorded during a guided mental imagery of an animal phobic object. Phobic stimulation induced in both groups the rise of heart and respiratory frequency and the lowering of skin resistance. These changes are less pronounced in Highs than in Lows and are sustained by a different modulation of the sympatho-vagal balance. During phobic stimulation both groups exhibited a similar significant increase of EEG gamma relative power. At variance, significant stimulation-related decrements of alpha1, theta1 and theta2 activities were found only in Highs that exhibited similar changes during the control and phobic stimulation. Results suggest that hypnotizability is able to modulate cerebral and autonomic responses also in specific phobic subjects. However, the presence of a specific phobia attenuates the effectiveness of hypnotizability as a protective factor against possible stress-related cardiac illness.  相似文献   
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