We analyse the role of entanglement for transmission of classical information through a memoryless depolarizing channel. Using the isotropic character of this channel we prove analytically that the ...mutual information cannot be increased by encoding classical bits into entangled states of two qubits.
CASES OF THE MONTH: April 2001 - June 2001 Hamilton, Ronald L.; Bleggi-Torres, L.F.; Reis-Filho, J. S. ...
Brain pathology (Zurich, Switzerland),
10/2001, Letnik:
11, Številka:
4
Journal Article
: Objective: Therapeutic splenectomy in myelofibrosis with myeloid metaplasia (MMM) may result in extreme thrombocytosis and leukocytosis and accelerated hepatomegaly. We previously described ...initial palliative benefit from 2‐chlorodeoxyadenosine (2‐CdA) in such instances. The purpose of this study is to provide long‐term follow‐up on the durability of response in the initial cohort and in additional subsequent cases. Methods: We retrospectively identified patients with histologically confirmed MMM who had palliative therapy with 2‐CdA. Clinical characteristics and information on subsequent clinical course were ed at the time of diagnosis of MMM and at initiation of 2‐CdA therapy until death. Results: To date, we have used 2‐CdA as palliative therapy in 14 patients with MMM. After a median of four cycles of therapy, responses for hepatomegaly occurred in 56% of patients, thrombocytosis 50%, leukocytosis 55%, and anemia 40%. Cytopenias were frequent but usually transient and without clinical consequence. Responses occurred usually by the second cycle; median duration of response was 6 months (range, 2–19) after completion of 2‐CdA therapy. Conclusion: This study confirmed relevant and frequently durable palliation of symptoms in about half the patients. 2‐CdA is a reasonable palliative option in postsplenectomy patients with MMM who have problematic myeloproliferation.
Abstract only
5554
Background: The epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) are commonly over- expressed in OC and may correlate with poor prognosis. EGFR ...mutations, although rare, have recently been reported in ovarian cancer. We examined these factors for prognostic value in the setting of treatment with BE. Results of a phase II trial of BE in recurrent OC pts have previously been reported; there were 1 CR and 1 PR among 13 patients. The trial was closed to accrual due to 2 bowel perforations. Methods: Pretreatment plasma VEGF, urine VEGF, and serum VEGFR2 levels are available on 9, 8, and 8 pts to date. VEGF levels were determined using an ELISA (R& D Systems, Minneapolis, MN). Tumor from 8 pts: 1(CR), 1 (PR), 5 (SD), 1 (PD) was available for immunohistochemical analysis for EGFR. Genomic DNA was successfully isolated from 6 paraffin embedded tumor specimens. EGFR exons 18 to 21 were amplified by PCR using primary and secondary PCR primer pairs. PCR products were purified and submitted for DNA sequencing against forward and reverse primers (analyzed with Sequencher). Results: Mean baseline plasma VEGF level was 107.6 pg/ml (range, 52–198 pg/ml). For analysis, we combined CR+PR+SD versus PD. Wilcoxon rank-sum test was used to compare baseline plasma VEGF levels, urine VEGF and serum VEGFR2 between the two response groups. There were no significant differences between response and baseline VEGF levels (p=0.39), urine VEGF (p=0.56), and VEGFR2 (p=0.56) respectively. The pt with prolonged CR (18 mos) had the highest baseline VEGF level. Cox proportional hazards regression models was used to look at the association between overall survival (OS) and VEGF levels. There was no significant relationship between (OS) and baseline plasma VEGF (p= 0.38), urine VEGF (p=0.33) or serum VEGFR2 (p=0.63) respectively. No EGFR mutations were found in exon 19 (n=4) or exon 21 (n=6). EGFR expression is being evaluated. Conclusions: Our results indicate that there were no significant relationship between response or OS and baseline VEGF or VEGFR2 levels in our treated pts. The study was supported by NCI Grant N01-CM-17102.
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We report the clinical, epidemiological and pathological findings of 14 patients with haemangioblastoma. Sixty-four percent occurred in males, with ages ranging from 16 to 60 years, with an average ...of 34, 4 years. Most of the tumours were confined to the cerebellum (n=9). The most frequent symptoms were headache (n=7) and dizziness (n=7), with a mean duration of 70 days. Von Hippel-Lindau syndrome (vHL) was diagnosed in 3 patients. Eleven patients were submitted to total surgical removal and in 3 the tumour was partially resected. A relapse rate of 28% in 3 years of follow-up was found. The patients with vHL showed recurrence in 66% of the cases. These findings corroborate those in current medical literature, showing an increased morbidity of this tumor when associated with vHL.
We have studied damping in polycrystalline Al nanomechanical resonators by measuring the temperature dependence of their resonance frequency and quality factor over a temperature range of 0.1-4 K. ...Two regimes are clearly distinguished with a crossover temperature of 1 K. Below 1 K we observe a logarithmic temperature dependence of the frequency and linear dependence of damping that cannot be explained by the existing standard models. We attribute these phenomena to the effect of the two-level systems characterized by the unexpectedly long (at least two orders of magnitude longer) relaxation times and discuss possible microscopic models for such systems. We conclude that the dynamics of the two-level systems is dominated by their interaction with one-dimensional phonon modes of the resonators.
Neurocysticercosis is the most frequent and widespread neuroparasitosis of the human being. The development of brain and leptomeningeal lesions, with subsequent symptoms, are mainly related with the ...immune status of the host, and to the number and evolutional phase of the parasites. We present the pathological findings in 27 necropsies of patients with neurocysticercosis, which accounted for 3.1% of the necropsies. 77% of the patients were male and the age ranged from 18 to 85 years. In 26% there was previous history of alcoholism. Clinicopathological study showed that 50% of the cases were classified as asymptomatic form, 11% epileptic form, 11% intraventricular form and 11% combined form. 33% of the patients presented seizures as a factor of aggravation of the clinical picture. There was a single cysticercus in 60% of the cases, the cellulosae form present in 82% and the racemous form in 7% of the cases; the remaining 11% had both forms present. In 30% of the patients the cause of death was directly related with the presence of the cysticercus in the central nervous system. Our findings confirm the high morbidity of this disease.