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D Simon

Publications and source records attributed to D Simon.

At least 55 records · Page 3Linked to original sources
PubMed2002

Subsidised oocyte donation in Israel (1998-2000): results, costs and lessons.

BACKGROUND: Israeli law stipulates that all women aged 45-51 who need oocyte donation are entitled to as many donations as necessary, up to the birth of one child. Only oocytes donated by women who themselves are undergoing assisted reproduction are allowed. The government subsidizes all oocyte donation cycles through the medical insurer of the recipient, whether or not the procedure is performed in a public or private institution. The aim of the present study was to investigate the success of oocyte donation cycles in Israel for the period 1998-2000 and to estimate costs and pregnancy rates. METHODS: Data were derived from the Dan District Registry of the General Health Services (Sheirutei Bri'ut Clalit), the largest medical insurer in Israel. RESULTS: 171 women underwent 254 oocyte donation cycles within these 3 years, and 45 babies were born, for a positive outcome of 17.7%. Average annual cycle cost was US$1742 and average annual cost per patient, US$2521. The total annual cost for the district accounted for only 0.05% of the budget. CONCLUSIONS: These findings suggest that IVF with donated oocytes is relatively efficient and that government funding of oocyte donation cycles ensures a reasonable cost.

Birth Rate↗
PubMed2001

Chromosomal assignments of mammalian genes with an acute inflammation-regulated expression in liver.

A set of acute inflammation-regulated genes expressed in liver has been assigned to rat, mouse, and human chromosomes by detecting species-specific PCR amplicons in rat(x)mouse or mouse(x)hamster somatic cell hybrids or radiation hybrids or by in silico matches of corresponding rat cDNAs to various libraries of previously assigned rat, mouse, or human genes or expressed-sequence tags. This allowed us to assign 24, 22, and 21 inflammation-regulated genes to rat, mouse, and human chromosomes, respectively. From these assignments as well as those previously determined for a larger set of genes with an acute inflammation-regulated transcription in liver, we further investigated whether such genes are clustered onto given chromosomes. A cluster was found on rat Chromosome (Chr) 6q with a conserved synteny on mouse Chr 12 and human Chr 14q13-q32, and another cluster previously reported on human Chr 1q has been extended with five further genes. Our data suggest that during an acute inflammation, a higher-order regulation may control some liver-expressed genes that share a given chromosome area.

Acute Disease↗
PubMed2001

Interaction of the octapeptide angiotensin II with a high-affinity single-chain Fv and with peptides derived from the antibody paratope.

The amino-acid sequence of the very high-affinity anti-angiotensin II monoclonal antibody 4D8 was predicted from the nucleotide sequence of the heavy and light chain variable genes. The single-chain variable fragment (scFv) was constructed and expressed in Escherichia coli as a soluble protein and at the surface of the filamentous M13 phage and was compared with the full-length antibody (Ab). The scFv showed the same specificity profile and affinity constant as the intact antibody (5.0x10(10) and 8.0x10(10) M(-1), respectively, by Scatchard analysis). Several peptides from the set of overlapping dodecapeptides covering the variable domains of 4D8 mAb were found to specifically bind biotinylated angiotensin II: peptides from the L1, L2, L3 and H1 regions had the strongest capacity to bind the antigen.

Amino Acid Sequence↗
PubMed2001

[Rectal carcinoma--oncologically adequate resection].

The local recurrence rate is besides distant metastatic spread the most relevant factor for the longterm survival of patients with rectal cancer. Of decisive importance are the experienced surgeon and special techniques such as the precise mesorectal dissection with respect of the holy planes. Total mesorectal excision (TME) for carcinomas of the lower and middle third of the rectum and a sufficient distal margin of 2 cm reduced the local recurrence rate to below 10% and allow sphincter preservation in more than 80%. The local excision is ideal for low-risk-patients with circumscript T1-tumors. In high-risk-patients the operation should be followed by additional chemoradiation therapy. Multivisceral surgery and pelvic exenteration do have a place in patients with locally advanced tumors, which should be treated by neoadjuvant radiochemotherapy. Laparoscopic operations of rectal cancer show first promising results but should, however, be restricted to controlled clinical trials.

Chemotherapy, Adjuvant↗
PubMed2001

Polarization measurements in high-energy deuteron photodisintegration.

We present measurements of the recoil proton polarization for the d(gamma-->,p-->)n reaction at straight theta(c.m.) = 90 degrees for photon energies up to 2.4 GeV. These are the first data in this reaction for polarization transfer with circularly polarized photons. The induced polarization p(y) vanishes above 1 GeV, contrary to meson-baryon model expectations, in which resonances lead to large polarizations. However, the polarization transfer Cx does not vanish above 1 GeV, inconsistent with hadron helicity conservation. Thus, we show that the scaling behavior observed in the d(gamma,p)n cross sections is not a result of perturbative QCD. These data should provide important tests of new nonperturbative calculations in the intermediate energy regime.

Journal Article↗
PubMed2001

Preferential loss of a polymorphic RIZ allele in human hepatocellular carcinoma.

The RIZ (PRDM2) locus commonly undergoes loss of heterozygosity (LOH) and maps within the minimal deleted region on 1p36 in hepatocellular carcinoma (HCC). Although peptide-altering mutations of RIZ are rare in HCC, the RIZ1 product is commonly lost in HCC and has tumour suppressive activities. Here, we analysed RIZ gene mutations and LOH in HCC, breast cancer, familial melanoma, colon cancer, and stomach cancer. We found 7 polymorphisms but no mutations. By analysing the Pro704-deletion polymorphism, we detected LOH of RIZ in 31 of 79 (39%) informative HCC cases, 11 of 47 (23%) colon cancer cases, 8 of 43 (19%) breast cancer cases, 8 of 66 (12%) stomach cancer cases. Importantly, loss of the Pro704(+)allele was found in 74% of the 31 LOH positive HCC cases (P< 0.01), indicating a preferential loss and hence a stronger tumour suppressor role for this allele compared to the P704(-)allele. In addition, the Pro704(+)allele was found to be more common in Asians (0.61) than Caucasians (0.42) (P = 0.0000), suggesting an interesting link between gene polymorphisms and potential differences in tumour incidence between racial groups.

Alleles↗
PubMed2001

Associations of blood lead, dimercaptosuccinic acid-chelatable lead, and tibia lead with neurobehavioral test scores in South Korean lead workers.

The authors performed a cross-sectional study to evaluate associations between blood lead, tibia lead, and dimercaptosuccinic acid (DMSA)-chelatable lead and measures of neurobehavioral and peripheral nervous system function among 803 lead-exposed workers and 135 unexposed controls in South Korea. The workers and controls were enrolled in the study between October 1997 and August 1999. Central nervous system function was assessed with a modified version of the World Health Organization Neurobehavioral Core Test Battery. Peripheral nervous system function was assessed by measuring pinch and grip strength and peripheral vibration thresholds. After adjustment for covariates, the signs of the beta coefficients for blood lead were negative for 16 of the 19 tests and blood lead was a significant predictor of worse performance on eight tests. On average, for the eight tests that were significantly associated with blood lead levels, an increase in blood lead of 5 microg/dl was equivalent to an increase of 1.05 years in age. In contrast, after adjustment for covariates, tibia lead level was not associated with neurobehavioral test scores. Associations with DMSA-chelatable lead were similar to those for blood lead. In these currently exposed workers, blood lead was a better predictor of neurobehavioral performance than was tibia or DMSA-chelatable lead, mainly in the domains of executive abilities, manual dexterity, and peripheral motor strength.

Adult↗
PubMed2001

Human hepatocellular carcinoma is characterized by a highly consistent pattern of genomic imbalances, including frequent loss of 16q23.1-24.1.

Comparative genomic hybridization (CGH) analysis was used to identify chromosomal imbalances in 52 human primary hepatocellular carcinomas (HCCs). The most prominent changes were gains of part or all of chromosome arms 8q (83% of cases) and 1q (73%) and loss of 16q (63%). Other commonly overrepresented sites were 5p, 7q, and Xq. Recurrent sites of DNA sequence amplification included 8q23--24 (five cases) and 11q13--14 (four cases). Other frequently underrepresented sites were 4q, 8p, 16p, and 17p. Taken collectively, these findings and data from other CGH studies of HCCs define a subset of chromosome segments that are consistently over- or underrepresented and highlight sites of putative oncogenes and tumor suppressor genes, respectively, involved in hepatocellular oncogenesis. Loss of heterozygosity analysis with a panel of polymorphic microsatellite markers distributed along 16q defined a minimal region of chromosomal loss at 16q23.1--24.1, suggesting that this region harbors a tumor suppressor gene whose loss/inactivation may contribute to the pathogenesis of many HCCs.

Allelic Imbalance↗
PubMed2001

Is there any consensus in diagnostic and operative strategy with respect to medullary thyroid cancer? A questionnaire answered by 73 endocrine surgical units.

BACKGROUND: The purpose of this investigation was to analyze the individual diagnostic and operative strategy in the treatment of medullary thyroid carcinoma (MTC) in international specialized centers and to assess whether standard procedures are carried out in practice everywhere. METHODS: A questionnaire concerning diagnosis and treatment of patients with primary, persistent, or recurrent sporadic or familial MTC was sent to 263 members of the International Association of Endocrine Surgeons. RESULTS: Primary treatment of MTC does not show significant differences for patients with sporadic or familial disease (Chi-square, n.s.), and standard procedures are performed in only 25-40% of patients. Computed tomography scan is the most common localization procedure in persistent or recurrent disease (52-72%), followed by scintigraphy (43-71%), ultrasonography (41-56%), and magnetic resonance imaging (31-49%). In case of negative localization studies, 68-86% of colleagues do not recommend reoperation. In symptomatic patients with stage-IV tumors, however, 84% of colleagues advocate reoperation to provide relief from the tumor burden. CONCLUSIONS: Even with experienced endocrine surgeons, a consensus to uni- and/or bilateral neck dissection in primary MTC is lacking. The majority of authors supports at least total thyroidectomy with central lymph-node dissection. In recurrent disease, there is a general tendency to reoperate in case of positive localization studies and in case of symptomatic disease.

Carcinoma, Medullary↗
PubMed2001

Tandem autotransplant as first-line consolidative treatment in poor-risk aggressive lymphoma: a pilot study of 36 patients.

PURPOSE: In the previous LNH87-2 study, consolidative high-dose therapy followed by stem cell transplantation (HDT) improved disease-free survival, as well as survival for patients (pts) presenting with two or three factors of the age-adjusted international prognostic index (Aa-IPI) in first complete remission (CR). In order to improve further the outcome of such patients, we conducted a pilot study of consolidative tandem autotranplant. PATIENTS AND METHODS: Thirty-six patients (pts) under 60 years of age with two or three factors of the Aa-IPI were enrolled. Their main characteristics were: diffuse large B-cell lymphoma (83%), Aa-IPI three factors (50%), and marrow involved (36)%. The procedure consisted of 1) induction with four cycles of ACVBP (doxorubicin, cyclophosphamide, vindesine, bleomycin, prednisone) 2) in responding pts, peripheral blood stem cell (PBSC) collection after the fourth cycle of ACVBP (11 pts) or after an additional mobilization regimen (Cyclophosphamide-VP16) (17 pts) 3) a first HDT (mitoxantrone, cyclophosphamide, VP16 and carmustine) followed by PBSC infusion 4) a second HDT (busulfan, carboplatin and melphalan) followed by PBSC infusion. Among the 29 patients responding to induction, 28 received the first HDTand 24 the second. RESULTS: The rates of three-year-event free survival and survival are 47% (95% confidence interval (95% CI: 31%-63%) and 50% (95% CI: 37%-69%), respectively. Eighteen patients remained free of evolutive disease and 18 patients have died, 15 from disease progression and three from treatment-related toxicity after tandem transplant (two veno-occlusive disease and one cerebral toxoplasmosis). CONCLUSION: We conclude that tandem transplant did not improve the results of the LNH87-2 study in which patients received a single consolidative HDT.

Adolescent↗
PubMed2001

The emergence of coherence over the course of decision making.

Previous research has indicated that decision making is accompanied by an increase in the coherence of assessments of the factors related to the decision alternatives. In the present study, the authors investigated whether this coherence shift is obtained before people commit to a decision, and whether it is obtained in the course of a number of other processing tasks. College students were presented with a complex legal case involving multiple conflicting arguments. Participants rated agreement with the individual arguments in isolation before seeing the case and after processing it under various initial sets, including playing the role of a judge assigned to decide the case. Coherence shifts were observed when participants were instructed to delay making the decision (Experiment 1), to memorize the case (Experiment 2), and to comprehend the case (Experiment 3). The findings support the hypothesis that a coherence-generating mechanism operates in a variety of processing tasks, including decision making.

Adult↗
PubMed2001

Mouse models for Friedreich ataxia exhibit cardiomyopathy, sensory nerve defect and Fe-S enzyme deficiency followed by intramitochondrial iron deposits.

Friedreich ataxia (FRDA), the most common autosomal recessive ataxia, is characterized by degeneration of the large sensory neurons and spinocerebellar tracts, cardiomyopathy and increased incidence in diabetes. FRDA is caused by severely reduced levels of frataxin, a mitochondrial protein of unknown function. Yeast knockout models as well as histological and biochemical data from heart biopsies or autopsies of FRDA patients have shown that frataxin defects cause a specific iron-sulfur protein deficiency and intramitochondrial iron accumulation. We have recently shown that complete absence of frataxin in the mouse leads to early embryonic lethality, demonstrating an important role for frataxin during mouse development. Through a conditional gene-targeting approach, we have generated in parallel a striated muscle frataxin-deficient line and a neuron/cardiac muscle frataxin-deficient line, which together reproduce important progressive pathophysiological and biochemical features of the human disease: cardiac hypertrophy without skeletal muscle involvement, large sensory neuron dysfunction without alteration of the small sensory and motor neurons, and deficient activities of complexes I-III of the respiratory chain and of the aconitases. Our models demonstrate time-dependent intramitochondrial iron accumulation in a frataxin-deficient mammal, which occurs after onset of the pathology and after inactivation of the Fe-S-dependent enzymes. These mutant mice represent the first mammalian models to evaluate treatment strategies for the human disease.

Animals↗
PubMed2001

Factors affecting hematopoietic recovery after autologous peripheral blood progenitor-cell transplantation in aggressive non-Hodgkin's lymphoma: a prospective study of 123 patients.

PURPOSE: To analyse prognostic factors influencing hematopoietic recovery in patients with aggressive non-Hodgkin's lymphomas prospectively treated with intensive chemotherapy followed by peripheral blood progenitor-cells transplantation. PATIENTS AND METHODS: Untreated patients with at least two unfavorable factors according to the age-adjusted international prognostic index were included in the LNH 93-3 trial. Patients received three cycles of chemotherapy and PBPC were mobilized using filgrastim. On day 60, a BEAM regimen was initiated followed by PBPC rescue. Among the 123 patients analysed, 60 received G-CSF (5 microg/kg/d) after PBPC transplantation at day 1 and 63 did not. RESULTS: Patients received a mean number of 12.4 x 10(6)/kg (1.86-111.5) CD34+ cells. After transplantation, neutrophil counts exceeded 0.5 x 10(9)/l at a median of 12.4 days (7-41 days) and platelet counts exceeded 50 x 10(9)/l at a median of 15.6 days (9-141 days). Platelets recovery > 50 x 10(9)/l was negatively influenced by BM involvement (20 s 14 days; P = 0.04). The number of CD34+ cells infused (> vs < or = 5 x 10(6)/kg) was correlated with faster platelet recovery (18.7 days vs 13.7 days) (P = 0.007). In 26 patients for whom administration of G-CSF was randomized, time to neutrophil recovery was significantly shorter for patients treated with G-CSF: 10 vs 13 days (P = 0.0005). The incidence of grade 3/4 infection, was similar in both groups. CONCLUSION: In the patient population treated with the same first-line regimen, BM involvement and infusion of fewer CD34+ cells delayed platelet recovery. Administration of G-CSF after PBPC significantly reduced neutropenia.

Adolescent↗
PubMed2001

Dendritic cell immunotherapy in a neuroendocrine pancreas carcinoma.

OBJECTIVE: Metastatic neuroendocrine carcinomas of the pancreas frequently fail to respond to conventional therapies, including radiation and chemotherapy. We therefore tested a dendritic cell-based immunotherapy in an attempt to eradicate residual tumour masses in a patient suffering from a metastatic insulin-producing pancreatic carcinoma. DESIGN: Autologous dendritic cells (DCs) were generated from peripheral blood monocytes in the presence of granulocyte/macrophage colony-stimulating factor, interleukin-4 and tumour necrosis factor alpha. DCs were loaded with tumour-derived lysate (TL), and were delivered by subcutaneous injections in 4-week intervals. RESULTS: Three weeks after first treatment, the patient developed a strong delayed-type hypersensitivity (DTH) skin reaction with an erythema and induration after the challenge with TL-pulsed DCs, which indicates the efficient generation of antigen-specific memory T-cells. Immunohistochemical analysis of skin biopsy demonstrated a strong perivascular and epidermal infiltration by T-helper (CD4 positive) and cytotoxic T cells (CD8 positive). Stimulation with TL revealed a dose-dependent T-cell proliferation with a stimulation index of 1.1-5.7 compared to 1.1-1.4 before vaccination (P < 0.01). Most strikingly, DC-based vaccination was accompanied by a steady decrease of the tumour marker chromogranin A from 2.93 umol/l initially to below the detection limit of 0.15 umol/l within 9 months of therapy. The ultrasound examination revealed a tumour regression of the metastasis in the right lobe of the liver. CONCLUSIONS: Our data indicate that vaccination with tumour lysate-pulsed DCs induced a significant antitumour immune response in a neuroendocrine carcinoma of the pancreas. This approach represents an alternative strategy for the treatment of advanced neuroendocrine carcinomas that are resistant to conventional therapy.

Adult↗
PubMed2001

Possibilities of flow cytometric analysis for immunophenotypic characterization of canine lymphoma.

The purpose of the study presented here is to show the possibilities of flow cytometric analysis for immunophenotypic characterization of canine malignant lymphoma. Aspiration biopsies from lymph nodes of 30 dogs with multicentric lymphoma were stained by four dog-specific antibodies and three human-specific antibodies cross-reacting with canine lymphocytes, and analysed by flow cytometry. Twenty of the 30 lymphoma examined were characterized as B-cell-lymphoma and 10 as T-cell-lymphoma. Flow cytometry is a suitable method for the immunophenotypic analysis of canine lymphoma. Contrary to immunohistochemistry, no surgically produced lymph node biopsy is required and the results are available within a few hours.

Animals↗