Phase I clinical and pharmacokinetic trial of Brequinar sodium (DuP 785; NSC 368390).

Brequinar sodium is a 4-quinolinecarboxylic acid analogue that inhibits dihydroorotate dehydrogenase and subsequent de novo pyrimidine biosynthesis. It has shown dose-dependent antineoplastic activity against several mouse and human tumor models. This trial evaluated Brequinar given as a single daily i.v. bolus over a 5-day period repeated every 28 days. One hundred seven courses of treatment at dosages ranging from 36 to 300 mg/m2/day x 5 were administered to 45 patients (31 male and 14 female) with refractory solid tumors; median age was 58 years (range 30-74); median Southwest Oncology Group performance status was 1 (range, 0-3). Thirty patients had prior cytotoxic chemotherapy. Dose-limiting toxicities were thrombocytopenia and a severe desquamative maculopapular dermatitis. Two of 5 good risk patients at 300 mg/m2 and 3 of 6 poor risk patients at 170 mg/m2 developed a platelet count less than 25 x 10(3)/microliters. Two of 5 good risk patients at 300 mg/m2 and 1 of 6 poor risk patients at 170 mg/m2 developed a severe desquamative dermatitis. Moderate to severe mucositis was usually associated with the thrombocytopenia and/or the dermatitis. Nonhematological drug-related toxicities included nausea and vomiting, malaise, anorexia, diarrhea, phlebitis, reversible transaminase elevation, and mucositis. Other hematological toxicities were anemia, granulocytopenia, and leukopenia. There were no drug-related deaths. There were no objective tumor responses. Plasma and urine levels of Brequinar were quantified by high pressure liquid chromatography in 28 patients. Plasma levels and areas under the curve increased proportionally with increased dose. Brequinar had a harmonic mean terminal t1/2 of 8.1 +/- 3.6 h with a model-independent determined apparent volume of distribution at steady state of 9.0 +/- 2.9 liters/m2 and a total body clearance of 19.2 +/- 7.7 ml/min/m2. Renal excretion was a minor route of elimination for Brequinar. The maximally tolerated dose of Brequinar on a daily x 5 i.v. schedule was 250 mg/m2 for good risk patients. For the daily x 5 i.v. schedule, the recommended dose of Brequinar for phase II evaluation is 250 mg/m2 for good risk patients and 135 mg/m2 for poor risk patients.

The hyperthermophilic bacterium, Thermotoga maritima, contains an unusually complex iron-hydrogenase: amino acid sequence analyses versus biochemical characterization.

The hyperthermophilic bacterium, Thermotoga maritima, grows up to 90 degrees C by fermenting carbohydrates and it disposes of excess reductant by H(2) production. The H(2)-evolving cytoplasmic hydrogenase of this organism was shown to consist of three different subunits of masses 73 (alpha), 68 (beta) and 19 (gamma) kDa and to contain iron as the only metal. The genes encoding the subunits were clustered in a single operon in the order hydC (gamma), hydB (beta), and hydA (alpha). Sequence analyses indicated that: (a) the enzyme is an Fe-S-cluster-containing flavoprotein which uses NADH as an electron donor; and (b) the catalytic Fe-S cluster resides within the alpha-subunit, which is equivalent to the single subunit that constitutes most mesophilic Fe-hydrogenases. The alpha- and beta-subunits of the purified enzyme were separated by chromatography in the presence of 4 M urea. As predicted, the H(2)-dependent methyl viologen reduction activity of the holoenzyme (45-70 U mg(-1)) was retained in the alpha-subunit (130-160 U mg(-1)) after subunit separation. However, the holoenzyme did not contain flavin and neither it nor the alpha-subunit used NAD(P)(H) or T. maritima ferredoxin as an electron carrier. The holoenzyme, but not the alpha-subunit, reduced anthraquinone-2,6-disulfonate (apparent K(m), 690 microM) with H(2). The EPR properties of the reduced holoenzyme, when compared with those of the separated and reduced subunits, indicate the presence of a catalytic 'H-cluster' and three [4Fe-4S] and one [2Fe-2S] cluster in the alpha-subunit, together with one [4Fe-4S] and two [2Fe-2S] clusters in the beta-subunit. Sequence analyses predict that the alpha-subunit should contain an additional [2Fe-2S] cluster, while the beta-subunit should contain one [2Fe-2S] and three [4Fe-4S] clusters. The latter cluster contents are consistent with the measured Fe contents of about 32, 20 and 14 Fe mol(-1) for the holoenzyme and the alpha- and beta-subunits, respectively. The T. maritima enzyme is the first 'complex' Fe-hydrogenase to be purified and characterized, although the reason for its complexity remains unclear.

Heterologous expression and properties of the gamma-subunit of the Fe-only hydrogenase from Thermotoga maritima.

Thermotoga maritima is a hyperthermophilic bacterium that contains a complex, heterotrimeric (alpha(beta)gamma) Fe-only hydrogenase. Sequence analysis indicates that the gene encoding the smallest subunit (gamma), hydC, contains a predicted iron-sulfur cluster binding motif. However, characterization of the native gamma-subunit has been hampered by interference from and the inability to separate intact gamma-subunit from the other two subunits (alpha and beta). To investigate the function and properties of the isolated gamma-subunit, the gene encoding HydG was expressed in Escherichia coli. Two forms of the recombinant protein were obtained with molecular masses of 10 and 18 kDa, respectively. Both contained a single [2Fe-2S] cluster based on metal analysis, EPR and UV-visible spectroscopy. NH2-terminal sequencing revealed that the 10 kDa protein is a truncated form of the intact gamma-subunit and lacks the first 65 amino acid residues. The midpoint potential of the 18 kDa form was -356 mV at pH 7.0 and 25 degrees C, as measured by direct electrochemistry, and was pH dependent with a pK(ox) of 7.5 and a pK(red) of 7.7. The oxidized, recombinant gamma-subunit was stable at 80 degrees C under anaerobic conditions with a half-life greater than 24 h, as judged by the UV-visible spectrum of the [2Fe-2S] cluster. In the presence of air the protein was less stable and denatured with a half-life of approx. 2.5 h. The recombinant gamma-subunit was electron transfer competent and was efficiently reduced by pyruvate ferredoxin oxidoreductase from Pyrococcus furiosus, with a Km of 5microM and a Vmax of 9 U/mg. In contrast, native T. maritima hydrogenase holoenzyme and its separated alpha-subunit were much less effective electron donors for the gamma-subunit, with a V(max) of 0.01 U/mg and 0.1 U/mg, respectively.

Clinical usefulness of an algorithm for the early diagnosis of spinal metastatic disease.

We have previously reported an algorithm that invokes several imaging modalities in the early detection of metastatic and benign disease of the spine in patients with cancer (J Clin Oncol 4:576, 1986). The development of new lesions (shown by Tc99m bone scans) in cancer patients with normal neurological examinations is further evaluated with plain radiographs, spinal computed tomography (CT), and CT myelography (CT-M). Of 60 patients in the original study, 28% were diagnosed as having only benign disease and the remainder had spinal metastases. Thecal sac impingement was seen in 47% of patients with metastatic disease and disruption of the posterior vertebral cortex was noted in all patients with epidural compression. We now report the 2-year follow-up of 55 of these patients. Without treatment, the 17 patients diagnosed with benign disease have shown no evidence of local failure in the spine and median survival is greater than 27 months. Thirty-eight patients diagnosed with spinal metastases had a median survival time of 16.9 months. Radiation therapy directed by CT-M findings provided pain relief in 78% of patients with back pain and metastatic disease. No patient, including 19 with thecal sac impingement, developed clinical myelopathy. These results demonstrate the usefulness of an imaging algorithm for the early identification and distinction of spinal metastatic disease and benign disease in patients with cancer.

Spinal computed tomography and computed tomographic metrizamide myelography in the early diagnosis of metastatic disease.

New lesions were shown by Tc99m bone scans to have developed in sixty patients with known metastatic cancer or high-risk primary cancer and normal neurologic examinations; they were further evaluated with plain radiographs, spinal computed tomography (CT), and CT myelography (CT-M) according to an algorithm. Three groups were identified based on plain radiographs: group 1 (normal radiograph), group 2 (compression fracture as indicated by radiograph), group 3 (evidence of metastasis as indicated by radiograph). In group 1 (n = 18), spinal CT revealed that 33% of the patients had benign disease and 67%, metastases; epidural compression was seen in 25% of the patients with metastasis as indicated by CT-M. In group 2 (n = 26), CT-M disclosed that 38% had a benign compression fracture and 62% had metastases and that 63% of the patients with metastases had an epidural compression. In group 3 (n = 16), spinal CT revealed that 15 patients had metastases (one patient had benign disease). Epidural cord compression was seen in 47% of the patients with metastatic disease. In all groups, the presence of cortical bone discontinuity around the neural canal (seen in 31 patients) was highly associated with epidural compression (seen in 20 patients). Our approach allowed the early and accurate diagnosis of spinal metastasis and epidural tumor as well as the diagnosis of benign disease and was useful in planning optimal local therapy.

Extended administration of oral etoposide and oral cyclophosphamide for the treatment of advanced non-small-cell lung cancer: a Southwest Oncology Group study.

PURPOSE: We designed an all-oral regimen of etoposide and cyclophosphamide for use in advanced non-small-cell lung cancer. PATIENTS AND METHODS: Eligible patients were chemotherapy-naive and had histologically confirmed assessable or measurable stage IV non-small-cell lung cancer. Patients received etoposide 50 mg/m2/d orally days 1 through 14 and cyclophosphamide 50 mg/m2/d orally days 1 through 14 every 28 days. Doses on later cycles were adjusted for myelosuppression. RESULTS: Sixty-six patients (64 eligible patients) received 192 cycles of oral extended etoposide/cyclophosphamide therapy (median, two cycles; range, zero to 15). Therapy was well tolerated with the mean dose per cycle being 104% of the originally scheduled dose. Two patients (3%) achieved a complete response and six (9%) achieved a partial response. Leukopenia, anemia, nausea/vomiting, and alopecia were the most common toxicities. Median survival was 6 months, and the 1-year survival rate was 25.6%, comparable to more intensive treatments. CONCLUSION: Oral extended etoposide/cyclophosphamide is a well-tolerated alternative for the treatment of stage IV non-small-cell lung cancer and can be used as a basis for the design of further outpatient regimens.

Phase II trial of paclitaxel by 24-hour continuous infusion for relapsed non-Hodgkin's lymphomas: Southwest Oncology Group trial 9246.

PURPOSE: The Southwest Oncology Group (SWOG) recently conducted a multiinstitutional phase II trial to determine the complete response (CR) and partial response (PR) rates, toxicities, and progression-free and overall survivals of patients with relapsed non-Hodgkin's lymphomas (NHLs) treated with a 24-hour continuous infusion of paclitaxel at a dose of 175 mg/m2. PATIENTS AND METHODS: Sixty-six patients with relapsed NHL who had received minimal prior therapy (one prior chemotherapy regimen for intermediate- to high-grade NHL [44 patients] or one or two prior regimens for low-grade NHL [22 patients]) were premedicated with dexamethasone, diphenhydramine, and cimetidine and then treated with continuous intravenous infusion paclitaxel over 24 hours every 21 days. RESULTS: Eleven of 66 patients (17%) achieved rigorously documented objective remissions, including two CRs (3%) and nine PRs (14%). In addition, another five patients (8%) achieved apparent PRs on a single computed tomographic (CT) scan. Responses were brief, lasting a median of 3 months (5 months for indolent lymphomas and 3 months for intermediate- to high-grade lymphomas). Grade 4 or 5 granulocytopenia was the only common serious toxicity, and occurred in 42 of 66 patients (64%). CONCLUSION: Paclitaxel is generally well tolerated when given as a continuous infusion of 175 mg/m2 over 24 hours, despite predictable granulocytopenia. However, single-agent paclitaxel has modest clinical efficacy compared with other available treatments for relapsed NHL.

Paclitaxel and gemcitabine chemotherapy for advanced transitional-cell carcinoma of the urothelial tract: a phase II trial of the Minnie pearl cancer research network.

PURPOSE: To evaluate the toxicity and efficacy of combination chemotherapy with paclitaxel and gemcitabine in patients with advanced transitional-cell carcinoma of the urothelial tract. PATIENTS AND METHODS: Fifty-four patients with advanced unresectable urothelial carcinoma entered this multi-centered, community-based, phase II trial between May 1997 and December 1999. All patients were treated with paclitaxel 200 mg/m(2) by 1-hour intravenous (IV) infusion on day 1 and gemcitabine 1,000 mg/m(2) IV on days 1, 8, and 15; courses were repeated every 21 days. Patients who had objective response or stable disease continued treatment for six courses. RESULTS: Twenty-nine of 54 patients (54%; 95% confidence interval, 40% to 67%) had major responses to treatment, including 7% complete responses. With a median follow-up of 24 months, 16 patients (30%) remain alive and nine (17%) are progression-free. The median survival for the entire group was 14.4 months; 1- and 2-year actuarial survival rates were 57% and 25%, respectively. Seven (47%) of 15 patients previously treated with platinum-based chemotherapy responded to paclitaxel/gemcitabine. Grade 3/4 toxicity was primarily hematologic, including leukopenia (46%), thrombocytopenia (13%), and anemia (28%). Ten patients (19%) required hospitalization for neutropenia and fever, and one patient had treatment-related septic death. CONCLUSION: The combination of paclitaxel and gemcitabine is active and well tolerated in the first- or second-line treatment of patients with advanced transitional-cell carcinoma of the urothelial tract. Response rate and duration compare favorably with those produced by other active, first-line regimens. This regimen should be further evaluated in phase II and III studies, as well as in patients with compromised renal function.

Results of tuberculosis screening in applicants for migration in Vietnam and Cambodia.

SETTING: Pre-migration medical screening programmes in Ho Chi Minh City, Vietnam and Phnom Penh, Cambodia. OBJECTIVE: To compare the rates of newly diagnosed bacteriologically confirmed tuberculosis (TB) in a cohort of migration applicants in Vietnam and Cambodia with current estimates of the TB burden in these countries. DESIGN: Interviews and medical screening of 5108 Vietnamese and 910 Cambodian migration applicants who applied for an Australian visa. RESULTS: On initial testing, the rate of bacteriologically confirmed TB among the Vietnamese cohort was 157 per 100,000 population compared to 989/100,000 among the Cambodian cohort. When cases detected during follow-up testing were included, the rate in the Vietnamese cohort was 489/100,000 compared to 1209/100,000 in the Cambodian cohort. CONCLUSIONS: Although it has been suggested that the rate of newly diagnosed bacteriologically confirmed TB among migration applicants would underestimate the prevalence of TB in the Vietnamese and Cambodian populations, the rates found were substantially higher than current point estimates of the prevalence of TB, particularly for Vietnam. Our findings suggest that current published estimates of the tuberculosis burden in Vietnam and Cambodia may be conservative.

The association between subjective and clinical indicators of health in prospective Vietnamese migrants.

We conducted a cross-sectional survey of 1669 prospective Vietnamese migrants who had applied to migrate to Australia to describe the association between self-reported health status and several commonly used clinical indicators of health among prospective Vietnamese migrants. Participants were recruited from the International Organization for Migration's standardised medical screening program.' We found that clinical indicators of health are related to self-reported health status among prospective Vietnamese migrants. Self-reported health status, which was assessed using a modified version of the Short Form-36 health survey, was significantly associated with clinical indicators of health, including the number of body system abnormalities identified during medical screening, evidence of tuberculosis on chest radiograph, and self-reported weight loss over the previous six months. These findings support the validity of self-reported health status assessment among prospective migrants, although the assessment of subjective indicators of health during compulsory medical screening may be limited by reporting bias.

Phase II trial of recombinant DNA gamma-interferon in advanced colorectal cancer: a Southwest Oncology Group study.

Fifty evaluable patients with advanced colorectal cancer, but without prior chemotherapy or immunotherapy, were randomized to one of two schedules of recombinant gamma-interferon (rGIFN). Twenty-four evaluable patients received rGIFN as a 2-h intravenous infusion daily x 5 every other week at a starting dose of 4.0 x 10(6) IU/m2/day (arm I). Twenty-six evaluable patients received rGIFN as a 24-h continuous intravenous infusion daily x 5 every month at a starting dose of 2.6 x 10(6) IU/m2/day (arm II). Toxicities on both schedules included flu-like symptoms, fevers/rigors, nausea/vomiting, hypotension, leukopenia, hepatotoxicity, nephrotoxicity, diarrhea, anemia, confusion, and ileus. Toxicity appeared to be more severe on arm I. No antitumor responses were observed, with 95% confidence intervals of 0 to 14% for arm I and 0 to 13% for arm II.

Epidemiology of HIV infection among prostitutes in the Philippines.

Between 1985 and 1987, examinations for human immune deficiency virus (HIV) antibody were done on 25,392 prostitutes working in 64 cities throughout the Philippines. The country-wide seropositivity rate among prostitutes based on this sample was 0.8/1,000. Of the HIV cases, 85% were working in just two cities whose prostitute populations comprised 50% of the total sample. The average incidence rate for the same two cities after 1 year was 2.3/1,000. HIV antibody-positive women were enrolled in a case-control study to determine demographic and epidemiologic risk factors. This study involving 34 HIV-positive prostitutes and 61 randomly selected negative control prostitutes did not reveal any risk factors related to sexual or other types of behavior. A history of genital warts, a history of abnormal vaginal discharge, and cytomegalovirus antibody were significantly more frequent in the HIV-positive cases than in the controls; however, by logistic regression analysis, only an abnormal vaginal discharge was independently associated with HIV infection. Absence of any evidence of transmission by blood transfusion or i.v. drug abuse suggests that HIV was introduced by the heterosexual route.

Absence of leukocytes permissive to dengue 2 virus in the acute phase of dengue hemorrhagic fever.

Patients with primary dengue infection developed dengue 2 virus (D2V) permissive peripheral blood leukocytes (PBL) 2--3 weeks after infection. PBL from healthy individuals with dengue antibody were permissive to D2V in vitro, suggesting that immunologically mediated in vitro D2V permissiveness persists for a relatively long time after recovery from dengue infection. However, PBL obtained from second infection dengue hemorrhagic fever patients did not support D2V growth during the acute phase of illness but did so during convalescence. Leukocytes from dengue-immune patients with typhoid fever or non-dengue viral illness were permissive throughout both acute and convalescent phases of illness although there was tendency for increased permissiveness during convalescence. Acute phase PBL from DHF patients synthesized and secreted dengue neutralizing antibody in culture. Absence of D2V replication in these cultures was strongly, but not completely, correlated with antibody production. Other immunological mechanisms, in addition to antibody, may be operating in vitro or in vivo during acute phase dengue hemorrhagic fever to alter the permissiveness of PBL to D2V infection.

Interobserver variability in prostate cancer specific survival.

We evaluated the reliability of disease-specific survival (DSS) as an outcome measure in patients with carcinoma of the prostate (CaP). The records of 50 patients had a diagnosis of CaP and had expired were selected from the hospital tumor registry. Records were reviewed by six individuals and each individual was asked to specify cause of death as due to CaP or some other cause. DSS curves were generated based on the determinations of each reviewer. Although the DSS curves were generally parallel, a high degree of variability was seen at various intervals, leading us to conclude that DSS is dependent upon the individual reviewer. Published by Elsevier Science Inc.

Treatment of Schistosoma mekongi with praziquantel in Cambodian refugees in holding centres in Prachinburi Province, Thailand.

Eighty-four cases of schistosomiasis mekongi among Cambodian refugees in holding centres in Thailand received praziquantel at 30 mg/kg body-weight orally twice in one day. Those treated were admitted to hospital in order to observe side effects for 24 hours. Assessment of the efficacy of praziquantel was based on cure rates. Side effects observed consisted primarily of abdominal pain, anorexia, nausea, emesis and headache. These were generally mild and transient. Physical signs revealed mild hepatomegaly and splenomegaly. The cure rate obtained one month after treatment was 97.5% and by 2 to 12 months after treatment reached 100%.

Mixed-lineage acute myeloid leukemia associated with a suprasellar dysgerminoma.

An association between primary mediastinal germ cell tumors and hematologic malignancies has been recognized since 1985. We present a patient with a suprasellar germ cell tumor and an associated leukemia. A 20-year-old black female presented in December 1987 with a 6-month history of headaches and weight loss, confusion, polyuria, and polydipsia. Evaluation revealed hypernatremia, normal neurologic examination except poor recall, and an enhancing inhomogeneous suprasellar mass on cranial computed tomography. Biopsy of the mass diagnosed a dysgerminoma, which was treated with craniospinal radiation. In February 1988, the patient developed pancytopenia, which resolved with discontinuation of cimetidine and phenytoin. She did well until June 1988 when she presented with skin lesions over the trunk and extremities. Skin biopsy revealed a leukemic infiltration. She was admitted with a WBC 1,500/microliter (without blasts), Hb 11.6 g/dl, PLT 210,000 microliter. Bone marrow biopsy revealed hypercellularity with 50% blasts, demonstrating mixed-lineage acute myeloblastic leukemia (myelomonocytic-M4; megakaryoblastic-M7). The patient was induced with a standard Ara-C/daunorubicin regimen. Two weeks postinduction, she became septic and expired. An autopsy demonstrated leukemic involvement of the spleen, liver, bone marrow, and skin, without residual dysgerminoma. This represents the first reported case of suprasellar dysgerminoma associated with a mixed-lineage leukemia not related to chemotherapy.

Synthetic estimates of work loss disability for each state and the District of Columbia.

A method of synthetic estimation of health characteristics for local areas, devised by the National Center of Health Statistics, was evaluated in a recent study. In the method, local data on population are combined with national data on a given health characteristic to produce an indirect estimate of that characteristic. The health characteristic selected in the study was that of complete and partial work loss disability. Therefore, synthetic estimates of complete and partial work loss disability were calculated for each State by combining the estimated rates of such disability for the United States, specific to a set of demographic domains, with the data relating to the distribution of each State into this set of demographic domains. The synthetic estimates of complete and partial work loss disability for each State were then compared with the direct estimates available from the 1970 decennial census. For partial work loss disability, agreement between the synthetic and the direct estimates, as judged by the median percentage absolute difference, was fairly good; for complete work loss disability, agreement was rather poor. On the other hand, the correlation between the synthetic and the direct estimates was higher for complete work loss disability than for partial, partly because the synthetic estimates had a greater spread for complete work disability than for partial. The skewness of the distributions of the squared differences indicates that the evaluation based on median percentage absolute differences was more descriptive than the one based on mean square errors.

Effects of cost sharing in health insurance on disability days.

We assess how cost sharing for medical services affects restricted activity days (RADs) and work loss disability days (WLDs), using data from a controlled experiment. We grouped the experimental insurance plans into four categories, one providing free care and the other three requiring varying amounts of cost sharing. RADs per person per year decreased by one to two days with greater cost sharing, with the strongest effects among those of average or poor health status, especially the non-poor. Unlike RADs, WLDs showed no systematic differences by plan.

Expectations and experiences of patients with cancer participating in phase I clinical trials.

PURPOSE/OBJECTIVES: To describe the expectations and experiences of patients entering phase I clinical trials. DESIGN: Descriptive, exploratory, prospective. SETTING: A large military medical teaching center. SAMPLE: Thirty-seven adult patients completed the entry and exit interviews. Subjects had a good performance status, were middle aged, and had common tumor types. METHODS: Interviews using structured entry and exit questionnaires. MAIN RESEARCH VARIABLES: Expectations and experiences of patients in phase I clinical trials. FINDINGS: Patients expected slightly increased support from family members and received more support than expected. Patients' expectations for tumor response and increased communication with their physician were not met. Patients expected symptoms such as fatigue, nausea and vomiting, and weight loss to improve during therapy, yet their expectations were not met. CONCLUSIONS: One theme that emerged from the data was hope/optimism. An issue that needs further exploration is the extent to which patients accurately understand information in the consent form. Findings also support the importance of communication between the patient and family members and the healthcare team. IMPLICATIONS FOR NURSING PRACTICE: Oncology nurses can mediate the flow of information between physicians and patients. Oncology nurses can and should assess the patient's level of understanding of the clinical trial, the consent form, and potential side effects at the time of entry into the trial and intermittently during the course of therapy. Nurses must allow patients with cancer who are undergoing investigational therapy to maintain a level of hope, while realistically counseling them about their progress during phase I trial participation.