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P Brock

Publications and source records attributed to P Brock.

At least 19 recordsLinked to original sources
PubMed2006

Ethics and pharmaceutical medicine -- the full report of the Ethical Issues Committee of the Faculty of Pharmaceutical Medicine of the Royal Colleges of Physicians of the UK.

The practice of pharmaceutical medicine brings with it ethical challenges and dilemmas often very different from those encountered in the practice of clinical medicine. Having established a framework of guiding ethical principles, this report aims to look in some detail at specific areas of possible ethical concern to pharmaceutical physicians, offering practical advice and guidance on good practice. The report covers issues related to pharmaceutical research, including dissemination of research findings, communication with other health professionals and patients and involvement of pharmaceutical physicians and companies in the provision of patient services. The primacy of the interests of patients and the wider public is emphasised, and the possible impact of new developments in pharmaceutical technology is explored. It is hoped that the report will help those working in pharmaceutical medicine and act as a stimulus for wider discussion and debate.

Biomedical Research↗
PubMed2006

Guiding Principles for Pharmaceutical Physicians from the Ethical Issues Committee of the Faculty of Pharmaceutical Medicine of the Royal Colleges of Physicians of the UK.

Medical practitioners practising in the field of pharmaceutical medicine, whether in industry, regulatory bodies or an academic environment, are bound by the same ethical standards which apply to all doctors. Their work, however, leads to some very specific ethical considerations which may not be fully explored in ethical codes based in clinical medicine. This document aims to establish some guiding principles which should underpin a working ethical framework for pharmaceutical physicians. It clearly places the protection of patients (and research subjects) and the doctor's duties to wider society ahead of responsibilities to an individual employer while emphasising the importance of adherence to high standards of research, including dissemination of findings. These principles form the basis of a fuller report which offers more specific practical advice on possible ethical conflicts or dilemmas.

Clinical Trials as Topic↗
PubMed2004

Risk-adapted treatment for childhood hepatoblastoma. final report of the second study of the International Society of Paediatric Oncology--SIOPEL 2.

SIOPEL 2 was a pilot study designed to test the efficacy and toxicity of two chemotherapy (CT) regimens, one for patients with hepatoblastoma (HB) confined to the liver and involving no more than three hepatic sectors ('standard-risk (SR) HB'), and one for those with HB extending into all four sectors and/or with lung metastases or intra-abdominal extra hepatic spread 'high-risk (HR) HB'. SR-HB patients were treated with four courses of cisplatin (CDDP), at a dose of 80 mg/m(2) every 14 days, delayed surgery, and then two more similar CDDP courses. HR-HB patients were given CDDP alternating every 14 days with carboplatin (CARBO), 500 mg/m(2), and doxorubicin (DOXO), 60 mg/m(2). Two courses of CARBO/DOXO and one of CDDP were given postoperatively. Between October 1995 and May 1998, 77 SR-HB (10 of whom were actually treated with the HR protocol) and 58 HR-HB patients were registered and all 135 could be evaluated. Response rates for the entire SR-HB and HR-HB groups were 90% (95% CI 80-96%) and 78% (95% CI 65-87%), and resection rates were 97% (95% CI 87-99%) and 67% (95% CI 54-79%) including several children undergoing liver transplantation. For SR-HB patients, 3-year overall and progression-free survivals were 91% (+/-7%) and 89% (+/-7%) and for the HR-HB group 53% (+/-13%) and 48% (+/-13%), respectively. The short-term toxicity of these regimens was acceptable, with no toxic deaths. A treatment strategy based on CDDP monotherapy and surgery thus appears effective in SR-HB but, despite CT intensification, only half of the HR-HB patients are long-term survivors. For SR-HB patients, the efficacy of CDDP monotherapy and the CDDP/DOXO ('PLADO') combination are now being compared in a prospective randomised trial (SIOPEL 3).

Adolescent↗
PubMed2001

Structure and optical properties of several organic-inorganic hybrids containing corner-sharing chains of bismuth iodide octahedra.

Two organic-inorganic bismuth iodides of the form (H3N-R-NH3)BiI5 are reported, each containing long and relatively flexible organic groups, R. The norganic framework in each case consists of distorted BiI6 octahedra sharing cis vertexes to form zigzag chains. Crystals of (H3NC18H24S2NH3)BiI5 were grown from a slowly cooled ethylene glycol/2-butanol solution containing bismuth(III) iodide and AETH.2HI, where AETH = 1,6-bis[5'-(2' '-aminoethyl)-2'-thienyl]hexane. The new compound, (H2AETH)BiI5, adopts an orthorhombic (Aba2) cell with the lattice parameters a = 20.427(3) A, b = 35.078(5) A, c = 8.559(1) A, and Z = 8. The structure consists of corrugated layers of BiI5(2-) chains, with Bi-I bond lengths ranging from 2.942(3) to 3.233(3) A, separated by layers of the organic (H2AETH)(2+) cations. Crystals of the analogous (H3NC12H24NH3)BiI5 compound were also prepared from a concentrated aqueous hydriodic acid solution containing bismuth(III) iodide and the 1,12-dodecanediamine (DDDA) salt, DDDA.2HI. (H2DDDA)BiI5 crystallizes in an orthorhombic (Ibam) cell with a = 17.226(2) A, b = 34.277(4) A, c = 8.654(1) A, and Z = 8. The Bi-I bonds range in length from 2.929(1) to 3.271(1) A. While the inorganic chain structure is nearly identical for the two title compounds, as well as for the previously reported (H3NC6H12NH3)BiI5 [i.e., (H2DAH)BiI5] structure, the packing of the chains is strongly influenced by the choice of organic cation. Optical absorption spectra for thermally ablated thin films of the three organic-inorganic hybrids containing BiI5(2-) chains are reported as a function of temperature (25-290 K). The dominant long-wavelength feature in each case is attributed to an exciton band, which is apparent at room temperature and, despite the similar inorganic chain structure, varies in position from 491 to 541 nm (at 25 K).

Journal Article↗
PubMed2000

Cisplatin, doxorubicin, and delayed surgery for childhood hepatoblastoma: a successful approach--results of the first prospective study of the International Society of Pediatric Oncology.

PURPOSE: Hepatoblastoma (HB) is a rare malignant liver tumor which occurs almost exclusively in childhood. In the 1970s, survival was approximately 20% to 30%. Since the introduction of cisplatin (PLA) and doxorubicin (DO) into the chemotherapy regimens used to treat these patients, the survival rate has improved dramatically. In most recent studies, primary surgery preceded chemotherapy. In this study by the liver group of the International Society of Pediatric Oncology the aim was to improve survival and reduce operative morbidity and mortality by using preoperative chemotherapy. PATIENTS AND METHODS: After biopsy and assessment of pretreatment extent of disease all patients were treated with continuous 24-hour intravenous infusion of PLA 80 mg/m(2) followed by DO 60 mg/m(2) over 48 hours (PLADO). After four courses of this chemotherapy, patients were reassessed. Where possible, the primary tumor was resected and treatment completed with two more courses of chemotherapy. RESULTS: One hundred fifty-four patients were registered in the study, and 138 received preoperative chemotherapy. One hundred thirteen (82%) showed a partial response with tumor shrinkage and serial decrease of serum alpha-fetoprotein levels. One hundred fifteen patients had delayed surgery, and 106 (including six with liver transplants) had complete resection of primary tumor. Five-year event-free survival was 66%, and overall survival was 75%. CONCLUSION: This study demonstrates that international collaboration on a large scale is feasible. The toxicity of chemotherapy and morbidity of surgery were acceptable and the overall survival gratifyingly high. We now regard PLADO chemotherapy and delayed surgery to be the best available treatment for children with HB. Other treatment programs should be measured against this standard.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

Hepatoblastoma presenting with lung metastases: treatment results of the first cooperative, prospective study of the International Society of Paediatric Oncology on childhood liver tumors.

BACKGROUND: The prognosis of children who are affected by hepatoblastoma (HB) that presents with lung metastases has always been considered very poor. In light of the overall improvement in the survival of HB patients since the introduction of cisplatin (CDDP) in the therapeutic armament of this tumor, the question has been raised whether patients with metastatic HB also would benefit from this drug. The purpose of the current study was to address this issue by analyzing the treatment outcome of those patients presenting with metastases who entered into the first HB study on childhood liver tumors conducted by the International Society of Paediatric Oncology (SIOPEL 1). METHODS: SIOPEL 1 was a prospective, international, multicentric, single-arm study based on preoperative chemotherapy that was open to patient registration from January 1990 to February 1994. After undergoing a biopsy, patients received four courses of CDDP (80 mg/m(2) in a 24-hour, continuous infusion) on Day 1 followed by doxorubicin (60 mg/m(2) in a 48-hour, continuous infusion) on Days 2 and 3 (PLADO). Surgery was performed after four courses of PLADO and was followed by two more courses. Untreated children age < 16 years with biopsy-proven HB were eligible for the study. Metastatic spread was assessed by chest X-ray and, where available, lung computed tomography scan. RESULTS: Thirty-one of 154 children that entered into the trial presented with metastases. Eight children presently are alive with no evidence of disease (NED) after being treated with protocol therapy only (median follow-up, 60 months); nine children are alive with NED after having failed PLADO and having been rescued with alternative therapies (median follow-up, 80 months). The 5-year overall and event free survival rates for these children were 57% (95% confidence interval, 39-75%) and 28% (95% confidence interval, 12-44%), respectively. Persistent lung disease was the main reason for PLADO failure (17 of 23 patients; 74%). CONCLUSIONS: The SIOPEL 1 therapeutic strategy seems to cure 25% of the HB patients who present with metastases. However, further chemotherapy and the use of thoracotomies still can save significant numbers of these children.

Adolescent↗
PubMed2000

Pretreatment prognostic factors for children with hepatoblastoma-- results from the International Society of Paediatric Oncology (SIOP) study SIOPEL 1.

The aim of this study was to investigate the prognostic significance of pretreatment patient and tumour characteristics for overall (OS) and event-free (EFS) survival in 154 children affected by hepatoblastoma (HB) in the first prospective liver tumour study run by the International Society of Paediatric Oncology. The pretreatment characteristics studied were age, alpha-fetoprotein, platelet count, histology; from radiology: intrahepatic tumour extension (PRETEXT), lung metastases, enlarged hilar lymph nodes, vena cava or extrahepatic vena porta tumour extension and tumour focality. Five-year OS was 75% (95% confidence interval (CI) 68-82%) and EFS 66% (95% CI 59-74%). Both were univariately associated with PRETEXT and the presence of metastases. Additionally tumour focality and enlargement of hilar lymph nodes at diagnosis were univariately associated with EFS. In multivariate analysis, PRETEXT was the only predictor of OS; PRETEXT and metastases were predictors of EFS. There is a need to investigate further these factors to confirm their validity.

Adolescent↗
PubMed2000

Disease- and treatment-related elevation of the neurodegenerative marker tau in children with hematological malignancies.

Children acquire neuropsychologic dysfunctions after chemotherapy for hematologic malignancy. In this study, putative changes in levels of CSF-tau (a marker of neural dysintegrity) in leukemic children prior to and during chemotherapy were studied. Cerebrospinal fluid (CSF) samples were obtained before and during treatment from patients with B cell non-Hodgkin's lymphoma (NHL, n = 10), non-B cell acute lymphoblastic leukemia/NHL (non-B-ALL, n = 48), acute myeloid leukemia (AML, n = 9), other malignant diseases (n = 9), and six control children. A sandwich-type ELISA (INNOTEST hTAU-Ag) was used for measuring CSF-tau. Sixteen out of 50 patients with hematological malignancies, including the patients with proven leukemic CNS invasion, already showed high CSF-tau levels at baseline (>300 pg/ml). The pre-induction treatment for non-B-ALL, consisting of only corticosteroids and methotrexate (MTX), resulted in a significant increase of tau at day 8 (on average to 535 pg/ml). Larger increases as compared to baseline levels of CSF-tau were observed in patients treated for B-NHL with systemic vincristine, corticosteroids and cyclophosphamide, and intrathecal MTX (mean 776 pg/ml at day 8). In two AML patients with CNS invasion, CSF-tau increased during chemotherapy up to 1,500 and 948 pg/ml, respectively. In one non-B-ALL patient with MTX-induced clinical neurotoxicity, CSF-tau was above the detection limit of 2,000 pg/ml. Almost one-third of the patients with hematological malignancies had elevated CSF-tau levels at diagnosis. Transient high levels of CSF-tau, reaching levels observed in other neurodegenerative disorders, were observed during induction chemotherapy for non-B-ALL, B-NHL and CNS+ AML. The clinical implications of both observations will be the subject of further study.

Antineoplastic Agents↗
PubMed2000

Long-term results of three randomized trials (58831, 58832, 58881) in childhood acute lymphoblastic leukemia: a CLCG-EORTC report. Children Leukemia Cooperative Group.

We present here the long-term results of three randomized clinical trials conducted on children with newly diagnosed acute lymphoblastic leukemia (ALL) between 1983 and 1998 by the Children Leukemia Cooperative Group (CLCG) from EORTC. In study 58831/32, the overall event-free survival (EFS) rates (+/- s.e.) at 6 and 10 years were 66% +/- 1.8% and 65% +/- 1.8%, respectively, and the risk of isolated central nervous system (CNS) relapse was 6% +/- 1% and 7% +/- 1%, respectively. In patients with a standard risk of relapse the omission of cyclophosphamide had no adverse effect on disease-free survival rates at 10 years (trial 58831). In medium- and high-risk patients the omission of radiotherapy did not increase the risk of CNS or systemic relapse (trial 58832). In study 58881 (1989-1998) the overall EFS rate at 8 years was 68.4% +/- 1.2% and the risk of isolated CNS relapse was 4.2%+/-0.5%. In this trial which adressed three randomized questions, the following results were obtained: the combination of cytarabine at high doses with methotrexate at high doses during interval therapy did not improve prognosis. The addition of 6-mercaptopurine iv during maintenance increased the risk of late relapse. E. coli asparaginase was more toxic and has a higher efficacy than Erwinia asparaginase. Leukocyte counts >100 x 10(9)/l, specific genetic abnormalities, a poor initial response to steroids or a high level of minimal residual disease at early time points were consistently associated with an adverse prognosis in the 58881 trial.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Embryonal rhabdomyosarcoma with only numerical chromosome changes. Case report and review of the literature.

An embryonal rhabdomyosarcoma, presenting as a retroperitoneal mass in a 15-year-old girl, is reported. The histological and immunohistochemical picture was typical, except for the presence of focal chondroid differentiation. Interestingly, expression of the "muscle markers" desmin and alpha-sarcomeric actin was present in the latter areas. Cytogenetic analysis showed a hyperdiploid karyotype without structural chromosome changes. The pertinent literature on the subject is reviewed. Hyperdiploidy of the clonal type seems to occur frequently, but no characteristic karyotype is so far emerging.

Adolescent↗
PubMed1999

Autopsy-controlled prospective evaluation of serial screening for circulating galactomannan by a sandwich enzyme-linked immunosorbent assay for hematological patients at risk for invasive Aspergillosis.

Efforts to improve the diagnosis of invasive aspergillosis (IA) have been directed towards the detection of fungal antigens, including galactomannan (GM). However, previous evaluations of GM detection have been hampered by a lack of proven cases of IA and by a nonserial study design. This prospective study assessed the diagnostic value of serial screening for circulating GM by using a recently developed sandwich enzyme-linked immunosorbent assay (ELISA) for prolonged-neutropenic and/or steroid-treated patients with hematological disorders. Serum GM levels were monitored twice weekly for 186 consecutive patients at increased risk for IA. The patients were stratified according to the likelihood of IA (proven, probable, possible, and no evidence of IA) by using stringent criteria. Proven IA was defined by characteristic histopathological findings together with a positive culture for Aspergillus species. Autopsy and culture from autopsy specimens was used to verify both positive and negative test results. A total of 2,172 serum samples were tested from 243 episodes (mean, 9 samples/episode). Based on the analysis of 71 patients with confirmed disease status (culture and histology), the sensitivity and specificity of serial GM monitoring were 92.6 and 95.4%, respectively. The positive predictive value was almost 93%, the negative predictive value was 95%, and the efficacy was 94%. False-positive reactions occurred at a rate of nearly 8%, although this figure might have been overestimated. Less than 1% of all tested sera were considered inconclusive. In more than half of the cases, antigenemia was detected before clinical suspicion of IA (median, 6 days before). Serial determination of serum GM by the sandwich ELISA technique is a sensitive tool for the diagnosis of IA in hematological patients at risk. This approach may substantially influence clinical management with regard to preemptive and empirical antifungal therapy.

Adolescent↗
PubMed1998

Genetic heterogeneity of neuroblastoma studied by comparative genomic hybridization.

Comparative genomic hybridization (CGH) analysis was performed on 36 neuroblastomas of both low and high stage of disease. This study significantly increases the number of neuroblastoma tumors studied by CGH. Analysis of larger series of tumors is particularly important in view of the different clinical subgroups that are recognized for this tumor. The present data and a comparison with all published CGH data on neuroblastoma provide further insights into the genetic heterogeneity of neuroblastoma. Stage 1, 2, and 4S tumors showed predominantly whole chromosome gains and losses. A similar pattern of whole chromosome imbalances, although less frequent, was observed in stage 3 and 4 tumors, in addition to partial chromosome gains and losses. An increase in chromosome 17 or 17q copy number was observed in 81% of tumors. The most frequent losses, either through partial or whole chromosome underrepresentation, were observed for 1p (25%), 3p (25%), 4p (14%), 9p (19%), 11q (28%), and 14q (31%). The presence of 3p, 11q or 14q deletions defines a genetic subset of neuroblastomas and contributes to the further genetic characterization of stage 3 and 4 tumors without MYCN amplification (MNA) and 1p deletion. The present study also provides additional evidence for a possible role of genes at 11q13 in neuroblastoma. In a few cases, 1p deletion or MNA detected by FISH or Southern blotting was not found by CGH, indicating that the use of a second, independent technique for evaluation of these genetic parameters is recommended.

Adolescent↗
PubMed1998

Langerhans cell histiocytosis of the cervical spine: case report of an unusual location.

An unusual location for Langerhans cell histiocytosis of the cervical spine is presented. The osteolytic lesion, instead of being located in the vertebral body, was visualised in the left lateral mass of the fifth cervical vertebra, extending into the vertebral body and through the interapophyseal joint into the lateral mass of the fourth cervical vertebra.

Cervical Vertebrae↗
PubMed1997

Sensitive and reliable detection of genomic imbalances in human neuroblastomas using comparative genomic hybridisation analysis.

Deletions of the short arm of chromosome 1, extra copies of chromosome 17q and MYCN amplification are the most frequently encountered genetic changes in neuroblastomas. Standard techniques for detection of one or more of these genetic changes are karyotyping, FISH analysis and LOH analysis by Southern blot or PCR. Each of these techniques has its own particular limitations. More recently, comparative genomic hybridisation (CGH) was introduced for detection of genomic imbalances including deletions, duplications and gene amplification. We evaluated the sensitivity and reliability of CGH for detection of the most frequently encountered genetic changes in neuroblastoma. For this purpose a panel of well-characterised neuroblastoma cell lines as well as a series of 11 primary neuroblastomas was analysed. Our results show that CGH is a valuable tool for the genetic characterisation of neuroblastomas, both for the detection of frequently occurring genomic imbalances and for the identification of previously unnoticed genetic changes.

Child, Preschool↗