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G Bosshard

Publications and source records attributed to G Bosshard.

11 recordsLinked to original sources
PubMed2003

Assisted suicide bordering on active euthanasia.

A 44-year-old woman was almost completely paralysed after a severe brainstem haemorrhage. Even after several years of efforts at rehabilitation, she remained completely dependent on the help of others. However, a special device enabled her to administer (after careful preparation) liquids through the PEG catheter despite her poorly coordinated movements. Four years after the stroke, the woman joined a right-to-die society with the wish to bring her life to an end. A doctor working with this organisation prescribed her a lethal dose of pentobarbital. In the presence of her husband and her companion from the organisation, the woman administered herself the lethal substance by means of the device. On the basis of the fact that she herself had switched the device on this death was classed as (assisted) suicide.

Adult↗
PubMed2003

[How stable is the attitude of aged people towards life-extending measures? Results of a 3-year follow-up in nursing home residents].

OBJECTIVE: To explore the stability of attitude towards life-extending measures in aged people. METHOD: Face-to-face interviews of nursing home residents at an interval of 3 years (prospective longitudinal survey). RESULTS: During the first interview period in 1997 (n=50), 19 nursing home residents (38%) had advocated treatment with antibiotics in a hypothetical scenario of acute life-threatening pneumonia. 15 individuals (30%) had refused such treatment, while statements from a further 16 (32%) had been ambivalent. Three years later, 19 individuals could be re-interviewed (28 had died in the meantime, 3 suffered from advanced dementia). 16 of these expressed the same or a similar attitude towards the above scenario as they did three years earlier (correspondence 84.2%, p<0.01). CONCLUSION: The results indicate a high stability of attitude towards life-extending measures in aged people. This finding may have implications for the meaning of advance directives in geriatric long-term care.

Advance Directives↗
PubMed2002

Open regulation and practice in assisted dying.

The Netherlands, Oregon and Switzerland are the only areas in the world where assistance in dying has legally been practised in recent years. This article provides a detailed comparison of the history of the origins, legislation, monitoring systems and the extent of assistance in dying in these three places. It shows that the actual practice in Switzerland which, unlike Oregon, also allows assistance in suicide by means of infusions or gastric tubes, can today be technically quite similar to the permitted practice of active euthanasia on request in the Netherlands. Considering the preconditions restricting these practices, Swiss regulations are the most open, in that the law requires neither a medical second opinion (as in both the Netherlands and Oregon) nor the existence of a terminal illness (as in Oregon) as prerequisite to assistance in dying. In 2001, the proportion of assisted deaths (as reported to the authorities) in all deaths was almost ten times higher in the Netherlands (1.5% of all deaths) then in Oregon (<0.1% of all deaths) or Switzerland (0.2% of all deaths). The analysis of the different normative concepts underlying legislation reveals that in the Netherlands the basis for non-prosecution lies in the conflict of the physician's duties to respect life versus relief of suffering, while in the USA and in Switzerland the right-to-die concept plays a major role. These two concepts allow appreciation of distinctions between the roles of the physician in end-of-life practices and between assisted suicide and voluntary active euthanasia.

Euthanasia↗
PubMed1999

Differential toxicity of anticancer drugs on late (GM-CFC) and early (LTC-IC) hemopoietic progenitors in vitro.

The clinical hematological toxicity of cytotoxic drugs can be acute, with a nadir of neutrophil count after 2 weeks and recovery the following week, or subacute, with a nadir of neutrophil count after 3 weeks and recovery in the following 2-3 weeks. The explanation usually given for this difference is that drugs in the first group are more toxic to mature hemopoietic precursors, while drugs of the second type are more toxic to undifferentiated cells. In an attempt to verify this hypothesis, we compared in vitro the effect of toxic doses of etoposide and tallimustine as representatives of drugs with acute toxicity, and of BCNU, melphalan, and carzelesin as representatives of drugs with subacute toxicity. Their effects were studied separately on more differentiated and earlier progenitors represented by granulocyte-macrophage colony-forming cells (GM-CFC) and long-term culture-initiating cells (LTC-IC), respectively. Etoposide, melphalan, BCNU, and carzelesin showed higher toxicity in differentiated than in early precursors: the concentration of drug inhibiting 70% (ID70) of GM-CFC inhibited only by 10-40% the growth of LTC-IC. Tallimustine, in contrast, inhibited both GM-CFC and LTC-IC at comparable levels. These results do not correspond to the clinical pattern of myelotoxicity observed for those drugs. We conclude that the differential effects of antitumor drugs on later (GM-CFC) or earlier (LTC-IC) hemopoietic precursors may not represent a valid model for the pattern of myelotoxicity observed in humans.

Animals↗
PubMed1998

Hematotoxicity on human bone marrow- and umbilical cord blood-derived progenitor cells and in vitro therapeutic index of methoxymorpholinyldoxorubicin and its metabolites.

PURPOSE: MMDX [3'-deamino-3'-[2(S)-methoxy-4-morpholinyl] doxorubicin], an anthracycline derivative active in vitro and in vivo against multidrug-resistant tumors, is currently under investigation in phase I clinical trials. In vivo it is metabolically activated, resulting in more cytotoxic compounds. We determined in vitro the toxic concentration of a 1-h period of exposure to doxorubicin (DX), MMDX, and bioactivated MMDX on hematopoietic progenitors and tumor cell lines. METHODS: DX and MMDX were tested on both bone marrow- (BM) and cord blood (hCB)-derived clonogenic cells, whereas the metabolites were tested on hCB only. All substances were tested on seven tumor cell lines. RESULTS: BM cells proved to be twice as sensitive as hCB cells to cytotoxics, and MMDX was twice as toxic as DX against hCB cells; MMDX activated with normal rat-liver microsomes and with dexamethasone-induced rat microsomes were, respectively, 70 and 230 times more toxic than MMDX. A comparison of the cytotoxic concentrations on hematopoietic progenitors and tumor cells, revealed that DX and MMDX had 5-fold stronger activity on tumor cell lines than on granulocyte/macrophage colony-forming cells (GM-CFCs), whereas bioactivated MMDX showed comparable cytotoxicity against tumor cells and hematopoietic progenitors. CONCLUSIONS: MMDX metabolites are very potent but display a lower degree of tumor selectivity than MMDX. Strategies to reduce MMDX metabolization should be developed to optimize the therapeutic index of this new anthracycline.

Antibiotics, Antineoplastic↗
PubMed1997

Estimation of the haematological toxicity of minor groove alkylators using tests on human cord blood cells.

We evaluated the myelotoxicity and the anti-tumor potential of tallimustine, three of its analogues and carzelesin, with melphalan as reference substance. Tallimustine was tested by clonogenic assays on both human bone marrow (BM) and cord blood (hCB) cells, the other compounds on hCB only. The degree of inhibition of the haemopoietic progenitors GM-CFC, CFC-E and BFU-E was evaluated after exposure to different concentrations. The same schedules were tested on five tumour cell lines. We found that the dose-response curves for tallimustine on BM and hCB cells were similar. Carzelesin was shown to be the most potent of the substances tested and to be the one with the best in vitro therapeutic index; of the distamycin analogues, the one bearing an alpha-bromoacrylic group (FCE 25450) had the best index. For melphalan, tallimustine and carzelesin, the concentration inhibiting the growth of 70% of progenitor cells in vitro (ID70) was similar to the concentrations found in the serum of patients treated at the maximum tolerated dose (MTD). We conclude that hCB cells may be used instead of BM cells for in vitro myelotoxicity tests. Therapeutic indexes can be extrapolated from this model and could help in selecting the most promising analogue for further clinical development. The in vitro-active concentrations are similar to myelotoxic concentrations in patients, suggesting a predictive value for the assay.

Adult↗
PubMed1997

Clinical relevance of bcl-2(MBR)/J(H) rearrangement detected by polymerase chain reaction in the peripheral blood of patients with follicular lymphoma.

We evaluated the prognostic role of peripheral blood polymerase chain reaction (PCR) assay for detection of the bcl-2(MBR)/J(H) rearrangement in 59 patients with follicular lymphoma (FL) treated at our centre since 1989. Thirty-five (59%) patients were bcl-2/J(H) positive and 24 (41%) were negative in the peripheral blood at diagnosis. Peripheral blood bcl-2/J(H) rearrangement detection at diagnosis had no relation to overall survival (OS) and time to progression (TTP). Peripheral blood PCR assay was performed post treatment in 17 patients who were bcl-2/J(H) positive at diagnosis. Fourteen of the patients (82%, 95% CI 56-96%) became bcl-2/J(H) negative. Nine of these patients were further analysed during follow-up and, after several months, circulating cells carrying the bcl-2/J(H) rearrangement reappeared in five of the nine patients. Peripheral blood clearance of bcl-2/J(H)-positive cells was correlated with better overall survival (log-rank P < 0.05) but not with TTP. Our data confirmed that bcl-2(MBR)/J(H) rearrangement detection by PCR at diagnosis is not a prognostic factor in follicular lymphoma. In our series, clearance of circulating bcl-2/J(H)-positive cells appeared to correlate with better overall survival. Post-treatment examination of the peripheral blood by PCR may have clinical relevance for prediction of the survival pattern of the patients.

Genes, bcl-2↗
PubMed1997

Immunoglobulin heavy chain diversity genes rearrangement pattern indicates that MALT-type gastric lymphoma B cells have undergone an antigen selection process.

Gastric MALT lymphoma usually develops from chronic gastritis, the vast majority of which (>90%) is associated with Helicobacter pylori infection. We sequenced the third complementarity determining region (CDR3) of immunoglobulin heavy chain genes in 19 gastric MALT lymphoma clones to determine the pattern of variable (V), diversity (D) and joining (J) gene utilization during immunoglobulin gene rearrangement. DNA was extracted from paraffin-embedded sections and the rearranged CDR3 regions were amplified using a semi-nested polymerase chain reaction (with primers complementary to the conserved framework-three segment of the variable region [FR3A] and J regions). The DNA used for cloning and sequencing was obtained after purification of monoclonal bands excised from polyacrylamide gels. The N-D-N region specific to each clone was compared with known germline D sequences. Similarly to that observed in normal and leukaemic B cells, our series of gastric MALT lymphomas showed apparent preferential utilization of genes from the DXP family. In two cases no similarity between the CDR3 nucleotide sequences of the neoplastic clones and the known germline D sequences could be found. In 10/19 analysed alleles the lymphoma B-cell clones appeared to contain two D gene segments (D-D recombination), a rare occurrence in normal individuals but one which has been described as a significant event in the determination of idiotype expression and antigen-binding affinity. Remarkably, despite the use of different D and J segments, the resultant amino acid sequences matched in two patients, suggesting the presence of a common selecting antigen. The observed pattern of D gene rearrangement suggests that MALT lymphoma B-cell clones have undergone antigen selection, which seems to indicate that the antigen stimulation plays a pivotal role in the development of the lymphoma.

Amino Acid Sequence↗
PubMed1996

Clinical significance of bcl-2 (MBR)/JH rearrangement in the peripheral blood of patients with diffuse large B-cell lymphomas.

BACKGROUND: Approximately one-fourth of diffuse large B-cell lymphomas (DLCL) carry the bcl-2(MBR)/JH rearrangement caused by the t(14;18) translocation. The clinical significance of this rearrangement in patients with DLCL remains controversial. By polymerase chain reaction (PCR) we prospectively evaluated the prognostic relevance of the bcl-2 (MBR)/JH rearrangement present in circulating B-cells at the time of diagnosis. MATERIALS AND METHODS: The bcl-2 (MBR)/JH rearrangement was analysed by a nested-PCR method in peripheral blood samples of 51 HIV-negative patients with previously untreated DLCL. RESULTS: The bcl-2 (MBR)/JH rearrangement was detected in 16 cases (31%). Peripheral blood bcl-2 (MBR)/JH rearrangement detection by PCR at diagnosis was correlated with poor overall survival, lymphoma-specific survival and time to progression (log-rank P < 0.05). There was no statistically significant difference between the clinical characteristics at presentation of bcl-2/JH-positive and negative patients. CONCLUSIONS: The peripheral blood is a readily accessible tissue for this type of analysis, and this study indicates that detection of the t(14;18) translocation at presentation in the blood of patients with DLCL may presage a poor prognosis.

Chromosomes, Human, Pair 14↗