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Biomedical subjects

H J Long

Publications and source records attributed to H J Long.

At least 19 recordsLinked to original sources
PubMed2001

Comparison of conventional dose and double dose carboplatin in patients receiving cyclophosphamide plus carboplatin for advanced ovarian carcinoma: a North Central Cancer Treatment Group Study.

Between March 1992 and November 1994, 91 patients with stage III and IV ovarian carcinoma were enrolled in a randomized comparative study of cyclophosphamide 600 mg/m2 plus carboplatin 300 mg/m2 vs. cyclophosphamide 600 mg/m2 plus carboplatin 600 mg/m2, each regimen given monthly for six cycles. Patients on the intensive regimen also received 10 micrograms/kg of granulocyte macrophage colony stimulating factor (GM-CSF) (molgramostim) daily for 14 days following each chemotherapy treatment. The study was closed prematurely because of very poor case accrual following the preliminary announcement (in May 1993) that paclitaxel appeared superior to cyclophosphamide in the platinum-based treatment of ovarian cancer. More than 4 years after our last case entry, we analyzed the survival results for the 44 eligible patients who received the conventional dose of carboplatin and the 43 eligible patients receiving our intensified dose of carboplatin. More than 90% of the treated patients receiving the conventional dose regimen received at least 75% of the planned doses at each of the six treatment intervals, whereas the percentage of treated patients able to receive at least 75% of the assigned intensive dose regimen had declined from 95% in cycle 2 to 53% by cycle 6. Furthermore, although 32 patients received all six planned cycles of treatment in the conventional regimen group, only 15 received all six cycles of the intensified regimen. Patients receiving the intensive regimen had more fever, dermatitis, lethargy, musculoskeletal pain, and pulmonary complications than did the conventional dose patients. Median survival times for the two treatment groups were very similar (38.5 and 38.1 months, respectively, for the conventional and intensive regimens), and we saw no evidence that the distribution of survival times differed between the treatment regimens (p = 0.95).

Adult↗
PubMed2000

Beta amyloid fragments derived from activated platelets deposit in cerebrovascular endothelium: usage of a novel blood brain barrier endothelial cell model system.

Amyloid precursor protein (A betaPP) processing results in generation of amyloid beta peptide (A beta) which deposits in the brain parenchyma and cerebrovasculature of patients with Alzheimer's disease (AD). Evidence that the vascular deposits derive in part from A betaPP fragments originating from activated platelets includes findings that individuals who have had multiple small strokes have a higher prevalence of AD compared to individuals who have taken anti-platelet drugs. Thus, determination of whether platelet A betaPP fragments are capable of traversing the blood-brain barrier (BBB) is critical. We have established that activated platelets from patients with AD retain more surface transmembrane-bound A betaPP (mA betaPP) than control platelets. We report here that this mA betaPP can be cleaved to A beta-containing fragments which pass through a novel BBB model system. This model utilizes human BBB endothelial cells (BEC) isolated from brains of patients with AD. These BEC, after exposure to activated platelets which have been surface-labeled with fluorescein and express surface-retained mA betaPP, cleave fluorescein-tagged surface proteins, including mA betaPP, resulting in passage to the BEC layer The data confirm that BEC contribute to processing of platelet-derived mA betaPP and show that the processing yields A beta containing fragments which could potentially contribute to cerebrovascular A beta deposition.

Adult↗
PubMed1999

Platelets and DAMI megakaryocytes possess beta-secretase-like activity.

We report here the discovery of two novel human platelet and megakaryocytic DAMI cell enzymes that have beta-secretase-like activity. These activities could potentially effect cleavage of the amyloid precursor protein (APP) at the beta-amyloid peptide N-terminus, by an EC 3.4.24.15-like metalloprotease, and the N terminus-1 position, by a serine protease. Thus both enzymes may generate the amyloidogenic beta-peptide. Studies of intact and Triton X-100-lysed DAMI cells, as well as intact versus subcellular fractions of platelets, demonstrate the presence of these proteolytic activities. The resting platelet has (1) a surface serine protease, demonstrated by its ability to cleave a beta-secretase substrate and by its inhibitor sensitivity; and (2) a metalloprotease, recognized by an antibody to EC 3.4.24.15, which resides intracellularly in the alpha-granule membrane, is translocated to the surface on activation, and shows beta-secretase-like activity by cleaving the same substrate. This metalloprotease can also cleave recombinant APP to a potentially amyloidogenic fragment. Surface metalloprotease was identified in DAMI cells by flow cytometry and Western blotting with a specific anti-EC 3.4.24.15 monoclonal antibody, while activity was identified by using two beta-secretase substrates. This article is the first to document two previously unknown endoproteinases with beta-secretase-like activity in platelets and DAMI cells. These proteases are capable of effecting cleavage of APP and could therefore contribute to Abeta deposition in the cerebrovasculature.

Alzheimer Disease↗
PubMed1999

Phase III clinical trial of the combination of cisplatin, dacarbazine, and carmustine with or without tamoxifen in patients with advanced malignant melanoma.

PURPOSE: A prospective randomized phase III clinical trial was conducted to assess whether the addition of tamoxifen (TAM) to the three-agent regimen of cisplatin (CDDP), dacarbazine (DTIC), and carmustine (BCNU) significantly increased the progression-free survival and overall survival of patients with advanced malignant melanoma. PATIENTS AND METHODS: Patients with advanced malignant melanoma were treated with CDDP + DTIC + BCNU (CDB) with or without TAM. The dose schedule was CDDP 25 mg/m(2) given intravenously (IV) for 30 to 45 minutes in 500 mL of dextrose and (1/2) normal saline (NS) on days 1 to 3 of a 3-week cycle; DTIC 220 mg/m(2) IV for 1 hour in 500 mL of dextrose and (1/2) NaCl on days 1 to 3 of a 3-week cycle; BCNU 150 mg/m(2) IV for 2 to 3 hours in 750 to 1,000 mL of dextrose and 5% water on day 1 of every odd 3-week cycle; and TAM 20 mg taken orally every morning. RESULTS: There were 184 eligible patients enrolled. These patients were observed until death or for a minimum of 1.3 years. At last contact, 12 were still alive. The median time to progression was 3.4 months on the CDB arm and 3.1 months on the CDB + TAM arm. The median survival time was 6.8 months with CDB and 6.9 months with CDB + TAM. Progression-free survival (P =.429) and overall survival (P =.545) were not found to differ by treatment. CONCLUSION: The addition of TAM to this three-agent regimen of CDB was not found to provide a meaningful clinical advantage in the treatment of patients with advanced malignant melanoma.

Adult↗
PubMed1998

Brain endothelial cell enzymes cleave platelet-retained amyloid precursor protein.

We have previously demonstrated that thrombin-activated platelets from patients with advanced Alzheimer's disease (AD) retain significantly more surface membrane-bound amyloid precursor protein (mAPP) than platelets from non-demented age-matched individuals (AM). We have studied interactions between these platelets and the cerebrovascular endothelium to which activated platelets adhere in a model system, investigating their involvement in the formation of amyloid beta peptide (Abeta) deposits in AD patients. We report here that there appear to be alpha and beta secretase-like activities in primary human blood brain barrier endothelial cell (BEC) cultures from both AD patients and AM control subjects (AD-BEC and AM-BEC, respectively) as well as a gamma secretase-like activity that appears only in AD-BEC. No such activities were observed in human umbilical vein endothelial cells (HUVECs). Furthermore, there is more penetration of the platelet-released products platelet factor 4 and soluble APP through the BEC layer grown from AD patients than that grown from AM individuals, whereas none penetrate through a HUVEC layer. Thus the interaction between platelets, the APP they have retained or released, and cerebral vascular endothelial cells may be at least partially responsible for amyloidogenic deposits around the cerebral vasculature of AD patients.

Adult↗
PubMed1998

Blood brain barrier endothelial cells express candidate amyloid precursor protein-cleaving secretases.

Proteolytic cleavage of the amyloid precursor protein (A beta PP) results in the generation of the amyloidogenic fragment known as amyloid beta peptide (A beta). Deposition of A beta in the brain parenchyma and cerebrovasculature is a feature of Alzheimer's disease (AD). To date, the process whereby A beta is generated and deposited remains unclear. We have previously established that activated platelets from AD patients retain more A beta PP on their surface than control platelets. We report here that an endothelial cell-derived enzyme can cleave this surface platelet A beta PP. Human blood brain barrier endothelial cells from brains of AD patients were assayed for potential A beta PP-cleaving enzymes using synthetic peptide substrates encompassing the A beta N-terminus cleavage site. A protease activity capable of cleaving A beta PP on the surface of AD platelets was noted. The A beta PP cleavage is partially inhibited by EDTA, by ZincOV, as well as by a specific inhibitor of the Zn metalloprotease E.C.3.4.24.15. Furthermore, the protease is recognized by an antibody directed against it, using immunohistochemistry, Western blot analysis and flow cytometry. The protease is not secreted, but rather resides intracellularly as well as on the surface of the endothelial cells. The data suggest that E.C.3.4.24.15 synthesized by brain endothelial cells may process the platelet-derived A beta PP, yielding fragments which could contribute to cerebrovascular A beta deposits.

Alzheimer Disease↗
PubMed1997

Can molgramostim enhance the antitumor effects of cytotoxic drugs in patients with advanced sarcomas?

BACKGROUND: A phase I study was designed for the amalgamation of two previously studied antisarcoma regimens (ifosfamide+doxorubicin and mitomycin+doxorubicin+cisplatin) supported by molgramostim. Thus, we hoped to develop a better regimen for the treatment of advanced sarcomas. PATIENTS AND METHODS: Fifteen adult advanced sarcoma patients and six other patients were registered and sequentially assigned to receive three progressively more myelosuppressive levels of chemotherapy: level I-ifosfamide 2500 mg/m2 + doxorubicin 40 mg/m2 + cisplatin 60 mg/m2 all given on day 0, followed by molgramostim 5 micrograms/kg every 12 hours for 14 days; level II-exactly the same chemotherapy from level I given on day 1 preceded on day 0 by ifosfamide 2500 mg/m2 and an additional four days of molgramostim given on days-6 through-3; level III-same as level II except for the addition of mitomycin 4 mg/m2 immediately prior to cisplatin on day 1. MENSA 500 mg/m2 was given five times on each day that involved ifosfamide treatment. For all levels, treatment was repeated at four-week intervals. RESULTS: Preliminary results and toxicity were reported three years ago (J Natl Cancer Inst 86: 312-4, 1994). Mature results confirm these unexpectedly favorable results with five advanced sarcoma patients still surviving after more than three years (four more than four years). HYPOTHESIS: Molgramostim given subcutaneously in a relatively intensive schedule might enhance the antitumor effects initiated by cytotoxic drugs in patients with advanced sarcomas. This idea should be tested formally in phase III studies.

Adult↗
PubMed1995

Phase II trial of methotrexate, vinblastine, doxorubicin, and cisplatin in advanced/recurrent carcinoma of the uterine cervix and vagina.

A phase II combination chemotherapy protocol combining methotrexate, vinblastine, doxorubicin, and cisplatin was designed to evaluate tumor response and survival in patients with advanced/recurrent cervix and vaginal cancer. Twenty-nine patients with advanced/recurrent cervix cancer and three patients with advanced vaginal cancer who had not previously received cytotoxic chemotherapy were assigned to chemotherapy treatment at 4-week intervals with methotrexate 30 mg/m2 i.v., Day 1, vinblastine 3 mg/m2 i.v., Days 2, 15, and 22, doxorubicin 30 mg/m2 i.v., Day 2, and cisplatin 70 mg/m2 i.v., Day 2. After a median of 4 cycles (maximum number 2 cycles beyond complete regression; 6 cycles with stable regression); we observed objective regressions in all 3 patients with vaginal cancer and 19 patients (66%, 95% CI = 46.82) with cervix cancer including complete regression in 6 patients (21%, 95% CI = 8.40) and partial regression in 13 patients (45%, 95% CI = 26.64). Median overall survival was 11.5 months (range 1.1-54+). Median survival of responders was 12.8 months (range 3.6-54+). Toxicity included neutropenia, alopecia, nausea, emesis, and stomatitis. Although grade 3 and 4 neutropenia was observed in over half of the patients, there were no treatment-related deaths. In conclusion, MVAC is a highly active outpatient chemotherapy regimen in patients with advanced/recurrent cervix cancer, achieving a high complete and partial response rate with moderate hematologic toxicity. These results need to be confirmed by phase III trial in advanced disease patients and MVAC may be a suitable regimen for investigation in neoadjuvant chemotherapy trials in poor prognosis, previously untreated patients.

Adult↗
PubMed1995

Phase II trial of methotrexate, vinblastine, doxorubicin, and cisplatin in advanced/recurrent endometrial carcinoma.

A phase II combination chemotherapy protocol combining methotrexate, vinblastine, doxorubicin, and cisplatin was designed to evaluate tumor response and survival in patients with advanced/recurrent endometrial carcinoma. Thirty patients with advanced/recurrent endometrial carcinoma were assigned to chemotherapy treatment at 4-week intervals with methotrexate 30 mg/m2 i.v. Days 1, 15, and 22; vinblastine 3 mg/m2 i.v. Days 2, 15, and 22; doxorubicin 30 mg/m2 i.v. Day 2; and cisplatin 70 mg/m2 i.v. Day 2. After a median of four cycles (maximum number two cycles beyond complete regression; minimum six cycles for stable partial regression), we observed objective regression in 20 patients (67%) (95% CI, 50, 84) with complete regression in 8 patients (27%) and partial regression in 12 patients (40%). Median overall survival was 9.9 months (range, 0.3-34.2), and median survival of responders was 11.0 months (range, 2.6-34.2) from initial date of response. Toxicity was substantial with two treatment-related deaths and consisted predominantly of neutropenia (grade 3 or greater in 93% of the patients), alopecia, nausea, emesis, stomatitis, and azotemia. In conclusion, MVAC is a highly active outpatient chemotherapy regimen in patients with advanced/recurrent endometrial carcinoma, achieving a high complete and partial response rate. Toxicity is substantial in this elderly patient population.

Adult↗
PubMed1994

Evaluation of piroxantrone in women with metastatic breast cancer and failure on nonanthracycline chemotherapy.

BACKGROUND: Doxorubicin generally is considered to be the most effective single chemotherapeutic agent for the treatment of breast cancer. The major cumulative dose-limiting toxicity is cardiac toxicity, which may be related to the formation of free radicals with subsequent lipid peroxidation, leading to membrane damage. The anthrapyrazoles, of which piroxantrone is a member, were synthesized in an attempt to eliminate this toxicity. METHODS: A Phase II clinical trial was conducted in 30 women with metastatic breast cancer in whom piroxantrone was administered at a dose of 160 mg/m2 by 1-hour infusion. The planned cycle length for retreatment was 3 weeks. Measurable metastatic disease and failure on one prior chemotherapy regimen, but no prior anthracycline exposure, were required for response evaluation. RESULTS: Twenty-nine patients were evaluable for response, and 6 (21% and 95% confidence intervals: 10-43%) achieved an objective response (1 complete, 5 partial responses), with a median response duration of 244 days. The median time-to-disease progression for all patients was 124 days. Eight patients received cumulative doses of piroxantrone approaching or exceeding 1000 mg/m2, and all had reductions in the resting left ventricular ejection fraction (LVEF). The estimated median decrease in LVEF at 1000 mg/m2 was 16%, with a range of 10-28%. Clinical findings of congestive heart failure developed in two patients. CONCLUSIONS: Piroxantrone had definite antitumor activity in women who had metastatic breast cancer and failure on prior chemotherapy that did not include an anthracycline. The 95% confidence interval for response probability was broad, but the level of activity observed was relatively low. The clear association with cardiac toxicity combined with the relatively low efficacy led to the conclusion that piroxantrone cannot be recommended for further development as therapy for women with breast cancer. Further study of other anthrapyrazoles is necessary to determine if the promise of this new class of agents can be fulfilled.

Adult↗
PubMed1994

Phase II evaluation of 5-fluorouracil and low-dose leucovorin in cisplatin-refractory advanced ovarian carcinoma.

Thirty-nine women with advanced, recurrent epithelial ovarian carcinoma who failed prior treatment with a platinum-based regimen were treated with leucovorin, 20 mg/m2 intravenously followed by 5-fluorouracil, 425 mg/m2 intravenously, daily for 5 consecutive days every 5 weeks in a phase II trial. Partial regressions were seen in 3 of 15 (20%) measurable disease patients, and objective regressions were seen in 3 of 14 (21%) evaluable/nonmeasurable disease patients. A 50% or greater decrease in CA-125 level was observed in 3 of 10 (30%) patients with no objectively evaluable or measurable disease. Overall objective response rate was 23% (95% confidence interval: 11 to 39%) in all 39 patients evaluated, with a median time to progression of 3 months and overall median survival of 7 months. Toxicities were acceptable and consisted of neutropenia, thrombocytopenia, stomatitis, and mild diarrhea. 5-Fluorouracil, as administered in this protocol, had modest antitumor activity in cisplatin-refractory ovarian carcinoma of short duration and minimal toxicity.

Adenocarcinoma↗
PubMed1994

Severe exfoliative dermatitis associated with hand ischemia during cisplatin therapy.

BACKGROUND: Platinum is one of the most widely used agents in clinical oncology today. Serious toxic effects are well recognized. FINDINGS: To our knowledge, the current report describes the first case of severe allergic exfoliative dermatitis associated with ischemia and necrosis of the hands in a patient who had received multiple doses of this agent. We postulate that the tissue damage was caused by vasospasm of small vessels from the initial injury triggered by platinum or its associated immune complexes. CONCLUSION: Platinum has become an integral part of combination chemotherapy for various solid tumors. Clinicians must recognize its toxic side effects and control them within tolerable limits.

Cisplatin↗
PubMed1994

Paclitaxel (Taxol): a novel anticancer chemotherapeutic drug.

OBJECTIVE: To review the literature on the clinical activity and toxic effects of paclitaxel (Taxol). DESIGN: Results of phase I and II trials of Taxol in patients with various types of tumors are provided. MATERIAL AND METHODS: Taxol is the first drug in a new class of antineoplastic agents known as the taxanes. These drugs demonstrate a novel mechanism of action characterized by promotion of the assembly of microtubules and stabilization of the tubules against depolymerization, resulting in mitotic arrest. RESULTS: Numerous phase I and phase II trials have demonstrated the efficacy of Taxol in refractory ovarian carcinoma, breast carcinoma, lung cancer, head and neck cancer, and lymphoma. Various durations of infusions of Taxol have been used in several studies. In the treatment of most patients with ovarian cancer, Taxol can probably be administered by either short infusion or 24-hour infusion with no compromise in antitumor effect. Neutropenia seems to be less common when 3-hour infusions are used. Additional phase II trials are currently in progress, as are combination chemotherapy trials. CONCLUSION: Taxol has definite antitumor activity in advanced ovarian and breast cancers and seems to have activity in lung cancer. Further clinical trials will determine the spectrum of activity of Taxol in other malignant tumors and define its role in combination chemotherapy for sensitive tumor types.

Dose-Response Relationship, Drug↗
PubMed1993

Localized ovarian cancer in the elderly. The Gynecologic Oncology Group experience.

BACKGROUND: The appropriate therapy for patients with localized (FIGO Stage I and II) ovarian cancer has been poorly defined for all age groups and particularly for the elderly. Few prospective randomized comparisons of adjuvant therapy after careful surgical staging have been performed. The Gynecologic Oncology Group (GOG) has performed a series of trials testing adjuvant treatment in carefully staged patients with early-stage ovarian cancer. Early trials included few elderly patients but the most recent trial (GOG 95) included 18% over the age of 65 years. METHODS: Comprehensive surgical staging defined by protocol is performed before randomization. Patients with predefined stages and histologies are included and the patients are randomized prospectively to receive either intraperitoneal phosphorus-32 or three monthly cycles of cyclophosphamide and cisplatin. Assessment of the value of this adjuvant therapy will depend on survival, disease-free survival, and relapse pattern differences between the two adjuvant therapies. RESULTS: This is an ongoing clinical trial and insufficient numbers of patients have been randomized for definitive conclusions. There have been seven recurrences on both arms of the trial with a median time to recurrence of 14 months. There currently are no significant age differences between relapsed patients and disease-free patients. At this point, 12 elderly patients have been randomized to each of the arms of therapy. CONCLUSIONS: Although no apparent survival differences exist for elderly patients in the most recent adjuvant chemotherapy trial of early ovarian cancer, the number of patients with cancer randomized and follow-up are insufficient to establish such a difference. Currently there is no evidence that elderly patients display a significant difference in relapse frequency or pattern.

Adult↗
PubMed1992

Granulocyte-macrophage colony-stimulating factor. Preliminary observations on the influences of dose, schedule, and route of administration in patients receiving cyclophosphamide and carboplatin.

BACKGROUND: In an attempt to learn how best to administer granulocyte-macrophage colony-stimulating factor (GMCSF), the authors performed a Phase I study of this agent. They were interested in the influences of dose, schedule, and route of administration on the effects of GMCSF in patients receiving standardized 1-day regimens of cyclophosphamide (CYCLO) and carboplatin (CBDCA). METHODS: Between June 1988 and March 1991, 57 patients with advanced cancer received GMCSF in association with CYCLO 1 g/m2 plus CBDCA 225-700 mg/m2. After the first dose escalation to 300 mg/m2 of CBDCA, patients who had previously received chemotherapy or radiation therapy were excluded. GMCSF was administered in three different doses, five different schedules, and by two different routes. Altogether, 17 different treatment groups were observed. In addition, 24-hour GMCSF serum concentration curves were charted in four patients. RESULTS: Using four sequential groups of three patients each who had received myelosuppressive treatment, treatment with CYCLO 1 g/m2 and CBDCA 225 mg/m2, the apparent superiority of daily subcutaneous injection over 30-minute daily IV infusion of GMCSF was demonstrated graphically. Subsequently, the authors observed apparent enhancement of GMCSF effects beyond those produced by the initially selected 20-day basic 10 micrograms/kg daily SC regimen beginning 2 days after chemotherapy. When administered SC every 12 hours for 14 days beginning the day after chemotherapy, GMCSF appeared to ameliorate the severity of both leukopenia and thrombocytopenia. These effects permitted escalation of the CBDCA dose to 700 mg/m2 (with 1 g/m2 of CYCLO) before cytotoxic tolerance limits were reached. Graphic small group comparisons suggest that GMCSF given SC in doses of 5 micrograms/kg twice daily may produce comparable leukocyte and platelet support after chemotherapy with lower toxicity than occurs from higher doses. Prechemotherapy priming with GMCSF twice daily for an additional 4 days (days -6 to -3) seems to ameliorate postchemotherapy cytopenias further but at the cose of some increased risk of GMCSF toxicity. Although most of the toxic effects of moderate-dose GMCSF are controlled by antihistamines and ibuprofen, oral glucocorticoids (e.g., prednisone, 10 mg twice daily during the second week of GMCSF administration) may be required in patients with serositis, pulmonary infiltrates, or severe skin eruptions. CONCLUSIONS: Our observations suggest that GMCSF should be administered SC in doses of approximately 5 micrograms/kg every 12 hours for 10-14 days beginning the day after chemotherapy. Prechemotherapy priming with these same doses for four additional days (days -6 to -3) may additionally ameliorate postchemotherapy leukopenia and thrombocytopenia, but with increased risk of toxicity.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

Phase II trial of intravenous hexamethylmelamine in patients with advanced ovarian cancer.

A Phase II trial of an intravenous preparation of Hexamethylmelamine was performed in ovarian cancer. Patients who had received prior Platinum based chemotherapy and had measurable disease were eligible. Among 15 evaluable patients, there were no objective responses. Two patients did show clinical and laboratory evidence of improvement. Toxicity was predominantly nausea and vomiting with minimal other toxicity. This intravenous form of Hexamethylmelamine has not shown meaningful activity in ovarian cancer patients who have failed prior platinum treatment.

Altretamine↗