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J Marsh

Publications and source records attributed to J Marsh.

At least 19 recordsLinked to original sources
PubMed2001

Alpha-interferon does not increase the efficacy of 5-fluorouracil in advanced colorectal cancer.

Two meta-analyses were conducted to quantify the benefit of combining alpha-IFN to 5FU in advanced colorectal cancer in terms of tumour response and survival. Analyses were based on a total of 3254 individual patient data provided by principal investigators of each trial. The meta-analysis of 5FU +/- LV vs. 5FU +/- LV + alpha-IFN combined 12 trials and 1766 patients. The meta-analysis failed to show any statistically significant difference between the two treatment groups in terms of tumour response or survival. Overall tumour response rates were 25% for patients receiving no alpha-IFN vs. 24% for patients receiving alpha-IFN (relative risk, RR = 1.02), and median survivals were 11.4 months for patients receiving no alpha-IFN vs. 11.5 months for patients receiving alpha-IFN (hazard ratio, HR = 0.95). The meta-analysis of 5FU + LV vs. 5FU + alpha-IFN combined 7 trials, and 1488 patients. This meta-analysis showed an advantage for 5FU + LV over 5FU + alpha-IFN which was statistically significant in terms of tumour response (23% vs. 18%; RR = 1.26;P = 0.042), and of a borderline significance for overall survival (HR = 1.11;P = 0.066). Metastases confined to the liver and primary rectal tumours were independent favourable prognostic factors for tumour response, whereas good performance status, metastases confined to the liver or confined to the lung, and primary tumour in the rectum were independent favourable prognostic factors for survival. We conclude that alpha-IFN does not increase the efficacy of 5FU or of 5FU + LV, and that 5FU + alpha-IFN is significantly inferior to 5FU + LV, for patients with advanced colorectal cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Effect of dopamine infusion on hemodynamics after hepatic denervation.

BACKGROUND: . The effects of dopamine (DA) on systemic hemodynamics are better understood than its effects on hepatic hemodynamics, especially after liver denervation occurring during liver transplantation. Therefore, a porcine model was used to study DA's effects on hemodynamics after hepatic denervation. MATERIALS AND METHODS: Fifteen pigs underwent laparotomy for catheter and flow probe placement. The experimental group (n = 7) also underwent hepatic denervation. After 1 week, all pigs underwent DA infusion at increasing doses (3-30 mcg/kg/min) while measuring hepatic parameters [portal vein flow (PVF), hepatic artery flow (HAF), total hepatic blood flow (THBF = HAF + PVF), portal and hepatic vein pressures] and systemic parameters [heart rate (HR), mean arterial pressure (MAP)]. RESULTS: There was a significant increase in HAF from baseline to the 30 mcg/kg/min DA infusion rate (within-subjects P < 0.01), but the differences between the two groups were not significant. PVF and THBF showed large effects (increases) with denervation, but the increase in flow with DA infusion was not present after denervation. Perihepatic pressures were unchanged by denervation or DA. Heart rate differed significantly between the control and denervated animals at baseline, 3, 6, 12 (all P < 0.05), and 30 mcg/kg/min DA (P = 0.10). Control vs denervation MAP at baseline was 100 +/- 4 vs 98 +/- 4 Torr and at 30 mcg/kg/min it was 110 +/- 3 vs 101 +/- 5 mm Hg. CONCLUSIONS: Hepatic flows tended to be higher after denervation. HAF showed similar increases with DA in both control and denervation groups. Increases in PVF and THBF with DA infusion were not present after denervation. HR was significantly decreased and MAP tended to be lower after denervation. The HR and MAP response to DA was similar in both groups. Therefore, both denervation and DA infusion have an effect on systemic and hepatic hemodynamics.

Animals↗
PubMed2001

Bradykinin modulation of tumor vasculature: I. Activation of B2 receptors increases delivery of chemotherapeutic agents into solid peripheral tumors, enhancing their efficacy.

Delivery of chemotherapeutic agents to solid peripheral tumors is compromised because the impaired microvasculature within and surrounding tumors limits diffusion and convection of agents from the vasculature to the tumor. Using a variety of rat tumor models, we show that intravenous administration of a vasoactive bradykinin B2 receptor agonist (Cereport, or labradimil; formerly RMP-7) enhances by nearly 3 times the delivery of the chemotherapeutic agent carboplatin, as well as the larger 70-kDa marker dextran, into ectopic and orthotopic solid tumors. This effect was selective for tumor tissue, with little or no increase seen in nontumor tissues and organs. Additionally, the increased carboplatin levels observed in tumors persisted for at least 90 min (the longest time point measured). In contrast to the consistent effects with hydrophilic compounds, delivery of the lipophilic, high protein-binding chemotherapeutics paclitaxel and 1,3-bis[2-chloroethyl]-1-nitrourea (BNCU) was not enhanced. Administration of Cereport with either carboplatin or another hydrophilic chemotherapeutic agent, doxorubicin, significantly increased efficacy of both agents, manifested by suppression of tumor growth and prolonged survival in tumor-bearing rats. These data demonstrate that delivery of chemotherapeutics to tumors can be pharmacologically increased (by stimulating bradykinin B2 receptors) without increasing the systemic exposure, or therefore, the toxic liability associated with higher chemotherapeutic doses.

Animals↗
PubMed2001

Bradykinin modulation of tumor vasculature: II. activation of nitric oxide and phospholipase A2/prostaglandin signaling pathways synergistically modifies vascular physiology and morphology to enhance delivery of chemotherapeutic agents to tumors.

Intravenous infusions of the bradykinin agonist Cereport (labradimil, formerly RMP-7) enhance delivery of concomitantly administered hydrophilic chemotherapeutic agents to solid tumors. The enhanced delivery produces greater in vivo efficacy of chemotherapeutic agents, manifested as suppressed tumor growth and increased survival in tumor-bearing rats. Here we elucidate the mechanisms of action involved with this unique phenomenon, at both the physical and biochemical levels. At the physical level we demonstrate that Cereport modifies the tumor vasculature in several important ways, including transient 1) reductions in interstitial fluid pressure within the tumor, 2) increases in pore size of the vasculature, and 3) increases in total vascular surface area. All three of these changes modify tumor-specific characteristics of the vasculature known to impede drug delivery to the tumor interstitium. Biochemically, we demonstrate that the activation of both of bradykinin's major signaling pathways, the nitric oxide and phospholipase A2/prostaglandin E2 are necessary events. Although pharmacologically blocking either pathway greatly reduced the effects of Cereport, stimulation of either pathway alone did not enhance delivery. However, simultaneous stimulation of both pathways (without exogenous bradykinin B2 receptor stimulation) produced a nearly 2-fold increase in delivery of carboplatin to the tumor. Thus, stimulation of endogenous bradykinin B2 receptors induces at least two parallel biochemical cascades that act synergistically to uniquely modify the tumor vasculature in ways that increase delivery and efficacy of chemotherapeutic agents.

Algorithms↗
PubMed2000

Set down in bone

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Journal Article↗
PubMed2000

Treatment of acquired severe aplastic anemia: bone marrow transplantation compared with immunosuppressive therapy--The European Group for Blood and Marrow Transplantation experience.

Patients with severe aplastic anemia (SAA) can be successfully treated with bone marrow transplantation (BMT) or immunosuppressive therapy (IS). The current outcome using both forms of therapy among 3,669 patients treated in Europe between 1976 and 1998 is reviewed. Significant progress has been made and the overall risk of failure is now low, with survival rates greater than 80% for both treatments. Chronic graft-versus-host disease (GvHD) remains a problem for BMT patients, and carries a high risk of lethal complications. On the other hand, IS patients are exposed to late failure due to relapse or clonal/malignant diseases. First-line BMT from identical siblings is compared with IS therapy in an intent-to-treat analysis of 1,765 patients, regardless of subsequent transplant status. The outcome of SAA patients has improved considerably over time and is influenced by patient variables such as severity of the disease and age, but also by the choice of the initial treatment.

Anemia, Aplastic↗
PubMed2000

Injectable chemotherapeutic microspheres and glioma I: enhanced survival following implantation into the cavity wall of debulked tumors.

PURPOSE: Implantation of biodegradable polymers provides a powerful method to deliver high, sustained concentrations of chemotherapeutics to brain tumors. The present studies examined the ability of injectable polymeric microspheres, formulated to release carboplatin or BCNU for 2-3 weeks, to enhance survival in a rodent model of surgically-resected glioma. METHODS: Rat glioma (RG2) cells were implanted into the cortex of rats and allowed to grow for 10 days prior to surgical resection. Rats were given either surgical resection only, bolus injection (100 microg) or microspheres containing 10, 50, or 100 microg of carboplatin or BCNU. The microspheres were implanted, via hypodermic injection, either directly into the surgical cavity or into the tissue along the perimeter of the cavity. RESULTS: The order of survival among treatment groups was: no resection < resection only < bolus chemotherapy < sustained release chemotherapy. Carboplatin and BCNU did not differ in this respect and in each case, the enhanced survival achieved with sustained release was dose-related. However, the enhanced survival achieved with carboplatin was substantially greater when the microspheres were implanted into the perimeter wall of the resection cavity, compared to implantation into the cavity itself. The enhanced survival produced by carboplatin implants along the resection perimeter was associated with a significant attenuation of regrowth of the tumor. Finally, in a separate study in non-tumor brain, atomic absorption spectrophotometry revealed that while the microspheres produced significantly prolonged tissue levels of carboplatin relative to a bolus injection, carboplatin diffusion was limited to brain tissue extending primarily 0.5 mm from the injection site. CONCLUSIONS: These data demonstrate: (1) that sustained delivery of chemotherapy is superior to equipotent bolus doses following tumor resection, and (2) that direct injection of sustained release microspheres into the tissue surrounding a growing tumor mass may provide superior effects over injections into the surgical cavity. They also suggest that successful implementation of this approach in humans may require measures or circumstances that improve upon the limited spatial drug diffusion from the implantation site.

Animals↗
PubMed2000

Intravenous cereport (RMP-7) enhances delivery of hydrophilic chemotherapeutics and increases survival in rats with metastatic tumors in the brain.

PURPOSE: The following experiments determined whether intravenous infusions of Cereport enhance delivery of chemotherapeutics and prolong survival in rats with metastatic tumors in the brain. METHODS: Autoradiography and scintillation were used to examine uptake of the lipophilic (paclitaxel and carmustine) and the hydrophilic (carboplatin) chemotherapeutic agents, as well as the large hydrophilic marker, 70 kDa dextran. Cereport was also tested in combination with the chemotherapeutic drugs carboplatin, vinorelbine, gemcitabine and carmustine to determine if Cereport could enhance the survival benefit beyond that provided by chemotherapy alone. RESULTS: Cereport enhanced the uptake of carboplatin and dextran, but not paclitaxel or carmustine. The pattern of Cereport's uptake effect with carboplatin revealed that Cereport selectively increased the proportion of highly permeable regions. Survival was significantly enhanced when Cereport was combined with either carboplatin, vinorelbine, or gemcitabine, but not carmustine, compared to each chemotherapeutic agent alone. CONCLUSIONS: These data provide the first evidence that Cereport, or any receptor-mediated approach intended to enhance the permeability of the blood-brain tumor barrier, can increase the delivery hydrophilic drugs to metastatic tumors in the brain, increasing survival in tumor-bearing rats.

Animals↗
PubMed2000

Evaluation of the Applied Biosystems automated Taqman polymerase chain reaction system for the detection of meningococcal DNA.

In a period where the proportion of culture confirmed cases in the UK has been steadily declining, diagnosis by PCR has been used to increase the number of confirmed cases and provide additional epidemiological data. This report presents a comparative evaluation of the fluorogenic probe-based 5' exonuclease assay (Taqman) using the Perkin-Elmer Applied Biosystems automated sequence detection system 7700 with previously reported polymerase chain reaction enzyme-linked immunosorbent (PCR ELISA) assays for the detection of meningococcal DNA in CSF, plasma and serum samples. Taqman assays developed were based on the detection of a meningococcal capsular transfer gene (ctrA), the insertion sequence IS1106 and the sialytransferase gene (siaD) for serogroup B and C determination and compared with similar assays in a PCR ELISA format. The Taqman ctrA assay was specific for Neisseria meningitidis, however the IS1106 assay gave false positive reactions with a number of non-meningococcal isolates. Sensitivity of the Taqman ctrA, IS1106 and siaD assays testing samples from culture-confirmed cases were 64, 69 and 50%, respectively, compared with 26, 67 and 43% for the corresponding PCR ELISA assays. Improvements to the DNA extraction procedure has increased the sensitivity to 93 and 91% for the TaqMan ctrA and siaD assays, respectively, compared to culture confirmed cases. Since the introduction of Taqman PCR a 56% increase in laboratory confirmed cases of meningococcal disease has been observed compared to culture only confirmed cases. The developed Taqman assays for the diagnosis of meningococcal disease enables a high throughput, rapid turnaround of samples with considerable reduced risk of contamination.

Bacterial Proteins↗
PubMed2000

Current results of bone marrow transplantation in patients with acquired severe aplastic anemia. Report of the European Group for Blood and Marrow transplantation. On behalf of the Working Party on Severe Aplastic Anemia of the European Group for Blood and Marrow Transplantation.

We have analyzed 2,002 patients grafted in Europe between 1976 and 1998 from an identical twin (n = 34), from an HLA-identical sibling (n = 1,699) or from an alternative donor (n = 269), which included unrelated and family mismatched donors. The proportions of patients surviving in these three groups are, respectively, 91, 66 and 37%: major causes of failure were acute graft-versus host disease (GvHD) (11%), infection (12%), pneumonitis (4%), rejection (4%). In multivariate Cox analysis, factors predicting outcome were patient's age (p < 0.0001), donor type (p < 0.0001), interval between diagnosis and bone marrow transplantation (BMT) (p < 0.0005), year of BMT (p = 0.0005) and female donor for a male recipient (p = 0.02). Patients were then divided in two groups according to the year of BMT: up to or after 1990. The overall death rate dropped from 43 to 24% (p < 0.00001). Improvements were seen mostly for grafts from identical siblings (from 54 to 75%, p < 0.0001), and less so for alternative-donor grafts (from 28 to 35%; p = 0.07). Major changes have occurred in the BMT protocol: decreasing use of radiotherapy in the conditioning regimen (from 35 to 24%; p < 0.0001) and increasing use of cyclosporin (with or without methotrexate) for GvHD prophylaxis (from 70 to 98%; p < 0.0001). In conclusion, the outcome of allogeneic BMT for patients with severe aplastic anemia has considerably improved over the past two decades: young patients, grafted early after diagnosis from an identical sibling, have currently an over 80% chance of long-term survival. Transplants from twins are very successful as well. The risk of complications with alternative donor transplants is still high.

Acute Disease↗
PubMed2000

Intravenous cereport (RMP-7) modifies topographic uptake profile of carboplatin within rat glioma and brain surrounding tumor, elevates platinum levels, and enhances survival.

Several experiments studied the effects of i.v. infusions of the bradykinin agonist, Cereport (RMP-7), on permeability of the blood-brain tumor barrier in rat gliomas. First, the ability of Cereport to increase uptake of two poorly blood-brain barrier-penetrating drugs (lypophilic paclitaxel and hydrophilic carboplatin) was directly compared to provide new information regarding the scope of delivery effects achieved with Cereport. Next, the increased uptake of platinum into tumor and brain surrounding tumor was shown to closely parallel that of radiolabeled carboplatin, confirming that delivery of a biologically active moiety is increased with Cereport. This study also demonstrated that the elevated tumor levels of platinum persisted for at least 2 h. The enhanced carboplatin uptake was then examined using a novel, high spatial resolution analysis of autoradiography. This revealed that the effects of Cereport were not uniform throughout the tumor, because it especially modified those areas normally impermeable to carboplatin. Finally, a range of i.v. Cereport doses (3.0 and 9.0 microg/kg) was tested in combination with carboplatin to determine whether increased survival might be achieved and to define the relationship between Cereport dose, plasma levels, uptake of carboplatin, and enhanced survival. Survival was enhanced only by the high dose of Cereport; the high dose also produced robust increases in carboplatin uptake and plasma concentrations of Cereport estimated to achieve the K(i), whereas the low dose did not. These data offer fundamental information regarding the effects of Cereport on delivery of chemotherapeutic agents to brain tumors and provide new insight into receptor-mediated permeability of the blood-brain tumor barrier.

Animals↗
PubMed2000

Consensus Conference on the Treatment of Aplastic Anemia.

This article presents guidelines for the diagnosis and treatment of aplastic anemia (AA) established by a consensus panel of investigators from various countries. The panel used the scientific evidence presented during the Consensus Conference forum and found in the scientific literature to prepare guidelines categorized as immunosuppressive therapy, unrelated bone marrow transplantation in patients with AA, and myelodysplasia/acute myeloid leukemia after immunosuppressive therapy.

Anemia, Aplastic↗
PubMed1999

Prospective randomized multicenter study comparing cyclosporin alone versus the combination of antithymocyte globulin and cyclosporin for treatment of patients with nonsevere aplastic anemia: a report from the European Blood and Marrow Transplant (EBMT) Severe Aplastic Anaemia Working Party.

We report the results of the first prospective randomized multicenter study of immunosuppressive treatment in patients with previously untreated nonsevere aplastic anemia (AA) as defined by a neutrophil count of at least 0.5 x 10(9)/L and transfusion dependence. Patients were randomized to receive cyclosporin (CSA) alone or the combination of horse antithymocyte globulin ([ATG] Lymphoglobuline; Merieux, Lyon, France) and CSA. The endpoint of the study was the hematologic response at 6 months. One hundred fifteen patients were randomized and assessable with a median follow-up period of 36 months; 61 received CSA and 54 ATG and CSA. In the CSA group, the percentage of complete and partial responders was 23% and 23%, respectively, for an overall response rate of 46%. A significantly higher overall response rate of 74% was found in the ATG and CSA group, with 57% complete and 17% partial responders (P =. 02). Compared with CSA alone, the combination of ATG and CSA resulted in a significantly higher median hemoglobin level and platelet count at 6 months. Fewer patients required a second course of treatment before 6 months due to a nonresponse. In the CSA group, 15 of 61 (25%) patients required a course of ATG before 6 months because of disease progression, compared with only 3 of 54 (6%) in the ATG and CSA group. The survival probabilities for the two groups were comparable, 93% (CSA group) and 91% (ATG and CSA group), but at 180 days, the prevalence of patients surviving free of transfusions, which excluded patients requiring second treatment because of nonresponse, death, disease progression, or relapse, was 67% in the CSA group and 90% in the ATG and CSA group (P =.001). We conclude that the combination of ATG and CSA is superior to CSA alone in terms of the hematologic response, the quality of response, and early mortality, and a second course of immunosuppression is less frequently required.

Adolescent↗
PubMed1999

Effectiveness of immunosuppressive therapy in older patients with aplastic anemia. European Group for Blood and Marrow Transplantation Severe Aplastic Anaemia Working Party.

BACKGROUND: Immunosuppressive therapy has been used for successful treatment of severe aplastic anemia, but little information is available on outcome in older patients. OBJECTIVE: To evaluate outcome in patients older than 50 years of age who received immunosuppressive therapy for aplastic anemia. DESIGN: Retrospective cohort study. SETTING: 56 centers of the European Group for Blood and Marrow Transplantation (EBMT). PATIENTS: 810 patients with aplastic anemia reported between 1974 and 1997. Patients were evaluated according to age group: 60 years of age or older (n = 127), 50 to 59 years of age (n = 115), and 20 to 49 years of age (n = 568; reference group). INTERVENTION: Antilymphocyte globulin, cyclosporine, or both. MEASUREMENTS: Survival, cause of death, response to treatment, relapse rate, and risk for late complications were analyzed in all patients and by age group. RESULTS: The 5-year survival rate was 57% (95% CI, 46% to 66%) in patients 50 to 59 years of age and 50% (CI, 39% to 60%) in patients 60 years of age or older compared with 72% (CI, 68% to 76%) in patients younger than 50 years of age (P < 0.001). Response to therapy, relapse rate, and risk for clonal complications were similar in all three age groups (P > 0.2). Age was significantly associated with an increased risk for death (relative risk compared with patients 20 to 49 years of age, 1.80 [CI, 1.29 to 2.52] for patients 50 to 59 years of age and 2.57 [CI, 1.87 to 3.53] for patients > or = 60 years of age), mainly because of bleeding or infection (P = 0.02). Response to immunosuppressive therapy in all patients at 12 months was 62% (CI, 58% to 66%); no difference was seen among the age groups in multivariate analysis (P > 0.2). Sixty-six of the 379 responding patients (17%) subsequently had relapse. The risk for clonal disorders at 10 years was 20% (CI, 15% to 27%). CONCLUSIONS: Response to immunosuppression in aplastic anemia is independent of age, but treatment is associated with increased mortality in older patients.

Adult↗
PubMed1999

CD44 expression in cervical intraepithelial neoplasia (CIN) and carcinoma.

BACKGROUND: The expression of the CD44 gene is markedly changed in many neoplastic tissues. The identification of tumor-specific CD44 expression patterns may aid tumor diagnosis. METHODS AND RESULTS: The transcription and translation of the CD44 gene were analyzed by reverse transcription polymerase chain reaction (RT-PCR), in situ hybridization and by immunohistochemistry. Samples were obtained from 24 normal and 24 neoplastic or malignant human cervical tissues. Southern blot hybridization analysis of RT-PCR products revealed an increase in the size and number of CD44 standard and variant transcripts in malignant cervical tissues compared with corresponding normal tissues. Misprocessing of mRNA was indicated in cervical carcinoma cells by the retention of intronic sequences. Multiple CD44 mRNA and protein isoforms were present throughout carcinoma tissues, whereas localization was restricted to the basal epithelium in normal cervical tissue. Analysis of desquamated cervical cells from cases of cervical intraepithelial neoplasia stages I-III showed progressively deranged patterns of CD44 expression, with more alterations being detected in the more advanced stages. CONCLUSIONS: Marked alterations in CD44 expression occur in cervical tissues during progression to malignancy. CD44 expression analysis could aid the early diagnosis of cervical malignancy using minimally invasive methods.

Antigens, Neoplasm↗
PubMed1999

Heterogeneous spectrum of mutations in the Fanconi anaemia group A gene.

Fanconi anaemia (FA) is a genetically heterogeneous autosomal recessive disorder associated with chromosomal fragility, bone-marrow failure, congenital abnormalities and cancer. The gene for complementation group A (FAA), which accounts for 60-65% of all cases, has been cloned, and is composed of an open reading frame of 4.3 kb, which is distributed among 43 exons. We have investigated the molecular pathology of FA by screening the FAA gene for mutations in a panel of 90 patients identified by the European FA research group, EUFAR. A highly heterogeneous spectrum of mutations was identified, with 31 different mutations being detected in 34 patients. The mutations were scattered throughout the gene, and most are likely to result in the absence of the FAA protein. A surprisingly high frequency of intragenic deletions was detected, which removed between 1 and 30 exons from the gene. Most microdeletions and insertions occurred at homopolymeric tracts or direct repeats within the coding sequence. These features have not been observed in the other FA gene which has been cloned to date (FAC) and may be indicative of a higher mutation rate in FAA. This would explain why FA group A is much more common than the other complementation groups. The heterogeneity of the mutation spectrum and the frequency of intragenic deletions present a considerable challenge for the molecular diagnosis of FA. A scan of the entire coding sequence of the FAA gene may be required to detect the causative mutations, and scanning protocols will have to include methods which will detect the deletions in compound heterozygotes.

Base Sequence↗
PubMed1999

Bone marrow transplants for paroxysmal nocturnal haemoglobinuria.

Paroxysmal nocturnal haemoglobinuria (PNH) is a rare clonal haematological disorder characterized by intravascular haemolysis and increased risk of thrombosis. PNH is associated with bone marrow failure syndromes including aplastic anaemia, myelodysplasia and leukaemia. Bone marrow transplants are sometimes used to treat PNH, but small series and reporting biases make assessment of transplant outcome difficult. The outcome of 57 consecutive allogeneic bone marrow transplants for PNH reported to the International Bone Marrow Transplant Registry (IBMTR) between 1978 and 1995 was analysed. The 2-year probability of survival in 48 recipients of HLA-identical sibling transplants was 56% (95% confidence interval 49-63%). Two recipients of identical twin transplants remain alive 8 and 12 years after treatment. One of seven recipients of alternative donor allogeneic transplants is alive 5 years after transplant. The most common causes of treatment failure were graft failure and infections. Our results indicate that bone marrow transplantation can restore normal bone marrow function in about 50% of PNH patients.

Adolescent↗