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D Warren

Publications and source records attributed to D Warren.

At least 19 recordsLinked to original sources
PubMed2006

Genetic determinants of normal variation in coagulation factor (F) IX levels: genome-wide scan and examination of the FIX structural gene.

BACKGROUND: High-normal and elevated plasma FIX activity (FIX:C) levels are associated with increased risk for venous- and possibly arterial-thrombosis. OBJECTIVE: Because the broad normal range for FIX:C involves a substantial unknown genetic component, we sought to identify quantitative-trait loci (QTLs) for this medically important hemostasis trait. METHODS: We performed a genome-wide screen and a resequencing-based variation scan of the known functional regions of every distinct FIX gene (F9) in the genetic analysis of idiopathic thrombophilia project (GAIT), a collection of 398 Spanish-Caucasians from 21 pedigrees. RESULTS: We found no evidence for linkage (LOD scores <1.5) despite genotyping more than 540 uniformly-spaced microsatellites. We identified 27 candidate F9 polymorphisms, including three in cis-elements responsible for the increase in FIX:C that occurs with aging, but found no significant genotype-specific differences in mean FIX:C levels (P-values > or = 0.11) despite evaluating every polymorphism in GAIT by marginal multicovariate measured-genotype association analysis. CONCLUSIONS: The heritable component of interindividual FIX:C variability likely involves a collection of QTLs with modest effects that may reside in genes other than F9. Nevertheless, because the alleles of these 27 polymorphisms exhibited a low overall degree of linkage disequilibrium, we are currently defining their haplotypes to interrogate several highly-conserved non-exonic sequences and other F9 segments not examined here.

Adolescent↗
PubMed2001

Domain mapping of human PEX5 reveals functional and structural similarities to Saccharomyces cerevisiae Pex18p and Pex21p.

PEX5 functions as an import receptor for proteins with the type-1 peroxisomal targeting signal (PTS1). Although PEX5 is not involved in the import of PTS2-targeted proteins in yeast, it is essential for PTS2 protein import in mammalian cells. Human cells generate two isoforms of PEX5 through alternative splicing, PEX5S and PEX5L, and PEX5L contains an additional insert 37 amino acids long. Only one isoform, PEX5L, is involved in PTS2 protein import, and PEX5L physically interacts with PEX7, the import receptor for PTS2-containing proteins. In this report we map the regions of human PEX5L involved in PTS2 protein import, PEX7 interaction, and targeting to peroxisomes. These studies revealed that amino acids 1-230 of PEX5L are required for PTS2 protein import, amino acids 191-222 are sufficient for PEX7 interaction, and amino acids 1-214 are sufficient for targeting to peroxisomes. We also identified a 21-amino acid-long peptide motif of PEX5L, amino acids 209-229, that overlaps the regions sufficient for full PTS2 rescue activity and PEX7 interaction and is shared by Saccharomyces cerevisiae Pex18p and Pex21p, two yeast peroxins that act only in PTS2 protein import in yeast. A mutation in PEX5 that changes a conserved serine of this motif abrogates PTS2 protein import in mammalian cells and reduces the interaction of PEX5L and PEX7 in vitro. This peptide motif also lies within regions of Pex18p and Pex21p that interact with yeast PEX7. Based on these and other results, we propose that mammalian PEX5L may have acquired some of the functions that yeast Pex18p and/or Pex21p perform in PTS2 protein import. This hypothesis may explain the essential role of PEX5L in PTS2 protein import in mammalian cells and its lack of importance for PTS2 protein import in yeast.

Amino Acid Sequence↗
PubMed2001

A short course of induction chemotherapy followed by two cycles of high-dose chemotherapy with stem cell rescue for chemotherapy naive metastatic breast cancer.

A single cycle of high-dose chemotherapy with stem cell support (HDC) in women with responsive metastatic breast cancer (BC) consistently achieves over 50% complete and near complete response (CR/nCR). This significant cytoreduction results in a median event-free survival (EFS) of 8 months, and approximately 20% 3-year and 16% 5-year EFS in selected patients. To improve long-term outcomes, new strategies to treat minimal residual tumor burden are needed. Increased total dose delivered can be achieved with two cycles of HDC. Critical design issues include shortening induction chemotherapy to avoid development of drug resistance and the use of different agents for each HDC cycle. We have determined the maximum tolerated dose (MTD) for paclitaxel combined with high-dose melphalan in the context of a double transplant and explored the impact of a short induction phase. Between June 1994 and August 1996, we enrolled 32 women with metastatic BC on to this phase I double transplant trial. Induction consisted of doxorubicin 30 mg/m2/day days 1-3 given for 2 cycles every 14 days with G-CSF 5 microg/kg s.c. days 4-12. Stem cell collection was performed by leukapheresis in each cycle when the WBC recovered to above 1000/microl. Patients with stable disease or better response to induction were eligible to proceed with HDC. HDC regimen I (TxM) included paclitaxel with dose escalation from 0 to 300 mg/m2 given on day 1 and melphalan 180 mg/m2 in two divided doses given on day 3. HDC regimen II was CTCb (cyclophosphamide 6 g/m2, thiotepa 500 mg/m2, and carboplatin 800 mg/m2 total doses) delivered by 96-h continuous infusion. At the first dose level of 150 mg/m2 paclitaxel by 3 h infusion, four of five patients developed dose-limiting toxicity consisting of diffuse skin erythema and capillary leak syndrome. Only two of these five completed the second transplant. Subsequently, paclitaxel was delivered by 24-h continuous infusion together with 96 h of dexamethasone and histamine receptor blockade. This particular toxicity was not observed again. No toxic deaths occurred and dose-limiting toxicity was not encountered. Three patients were removed from study prior to transplant: one for insurance refusal and two for disease progression. All others completed both cycles of transplant. Complete and near complete response (CR/nCR) after completion of therapy was achieved in 23 (72%) of 32 patients. The median EFS is 26 months. The median overall survival has not yet been reached. At a median follow-up of 58 months, EFS and overall survival are 41% and 53%, respectively. This double transplant approach is feasible, safe, and tolerable. Treatment duration is only 14 weeks and eliminates lengthy induction chemotherapy. The observed event-free and overall survivals are promising and are better than expected following a single transplant. Whilst selection biases may in part contribute to this effect, a much larger phase II double transplant trial is warranted in preparation for a potential randomized comparison of standard therapy vs single vs double transplant.

Adult↗
PubMed2001

A short course of induction chemotherapy followed by two cycles of high-dose chemotherapy with stem cell rescue for chemotherapy naive metastatic breast cancer: sequential phase I/II studies.

Two cycles of high-dose chemotherapy with stem cell support (HDC) may increase the total dose delivered and dose intensity. A brief induction phase and different non-cross-resistant agents for each HDC cycle were used to avoid drug resistance. Twenty-six women with metastatic BC had induction and stem cell mobilization with two cycles of doxorubicin/G-CSF given every 14 days. Patients with stable disease or better after induction received HD CTCb followed by HD melphalan and dose-escalated paclitaxel. At 475 mg/m(2) of paclitaxel by 24-h infusion, dose-limiting transient peripheral sensory neuropathy was encountered. No toxic deaths occurred. Complete and near complete response after completion of therapy was achieved in 22 (85%) of 26 patients. The median EFS was 38 months. The median OS has not yet been reached. At a median follow-up of 33 (25-43) months, actuarial EFS and OS were 54% (95% confidence interval (CI), 39-69%) and 69% (95% CI, 56-79%), respectively. This double transplant approach lasts only 14 weeks and is feasible, safe, and tolerable. Whilst selection biases may in part contribute to favorable EFS and OS, a randomized comparison of standard therapy vs double transplant in both metastatic and locally advanced breast cancer is warranted.

Adult↗
PubMed2001

Cranberry juice consumption may reduce biofilms on uroepithelial cells: pilot study in spinal cord injured patients.

STUDY DESIGN: A pilot study of 15 spinal cord injured patients. OBJECTIVE: To determine whether alteration of fluid intake and use of cranberry juice altered the bacterial biofilm load in the bladder. SETTING: London, Ontario, Canada. METHODS: Urine samples were collected on day 0 (start of study), on day 7 following each patient taking one glass of water three times daily in addition to normal diet, and on day 15 following each patient taking one glass of cranberry juice thrice daily. One urine sample was sent for culture and a second processed to harvest, examine by light microscopy and Gram stain non-squamous uroepithelial cells to generate bacterial adhesion per 50 cells data. RESULTS: The results showed that cranberry juice intake significantly reduced the biofilm load compared to baseline (P=0.013). This was due to a reduction in adhesion of Gram negative (P=0.054) and Gram positive (P=0.022) bacteria to cells. Water intake did not significantly reduce the bacterial adhesion or biofilm presence. CONCLUSION: The findings provide evidence in support of further, larger clinical trials into the use of functional foods, particularly cranberry juice, to reduce the risk of UTI in a patient population highly susceptible to morbidity and mortality associated with drug resistant uropathogens. SPONSORSHIP: This study was funded by Ocean Spray Cranberries, Lakeville, MA, USA.

Acids↗
PubMed2001

Human papillomavirus-associated cervical cytologic abnormalities among women with or at risk of infection with human immunodeficiency virus.

OBJECTIVE: Correlates of abnormal human immunodeficiency virus cervical cytologic findings were examined among women infected with human immunodeficiency virus and uninfected women. STUDY DESIGN: We performed a cross-sectional analysis of baseline data on demographically similar women with infection or risk factors for it. RESULTS: Among 1050 women without hysterectomy, squamous intraepithelial lesions were more common among women infected with human immunodeficiency virus than among uninfected women (18.8% vs 5.3%; P <.001). In multivariate analysis the association of squamous intraepithelial lesions with human papillomavirus infection was strong; adjusted prevalence ratios were 27 for high-risk, 25 for intermediate-risk, and 10 for low-risk types (95% confidence intervals, 12-58, 12-54, and 4-25, respectively). Much lower adjusted prevalence ratios were seen for the only other factor significantly associated with squamous intraepithelial lesions, namely, infection with human immunodeficiency virus in conjunction with a reduced CD4(+) cell count. Adjusted prevalence ratios were 1.9 for CD4(+) cell counts <200 and 1.6 for CD4(+) cell counts between 200 and 500 (95% confidence intervals, 1.2-3.0 and 1.0-2.5, respectively). Adjusted attributable fractions calculated for this study population indicated that if both human immunodeficiency virus and human papillomavirus were removed, 47.6% of the observed lesions with atypical squamous cells of uncertain significance and 93.4% of the observed squamous intraepithelial lesions would be prevented. CONCLUSION: Squamous intraepithelial lesions are more common among human immunodeficiency virus-infected women and are associated most commonly with high- and intermediate-risk human papillomavirus types and secondarily with human immunodeficiency virus-associated immune compromise.

CD4 Lymphocyte Count↗
PubMed2001

A multicenter study of bacterial vaginosis in women with or at risk for human immunodeficiency virus infection.

BACKGROUND: Bacterial vaginosis is a common gynecologic infection that has been associated with a variety of gynecologic and obstetric complications, including pelvic inflammatory disease, postabortal infection and premature delivery. Recent studies suggest that bacterial vaginosis may increase a woman's risk for human immunodeficiency virus (HIV). We undertook this study to assess whether the prevalence and characteristics of bacterial vaginosis differed according to HIV status in high-risk US women. METHODS: Prevalence of bacterial vaginosis was assessed by Gram's stain and clinical criteria for 854 HIV-infected and 434 HIV-uninfected women enrolled in the HIV Epidemiology Research (HER) Study. Multiple logistic regression techniques were used to determine whether HIV infection independently predicted bacterial vaginosis. RESULTS: Almost half (46%) the women had bacterial vaginosis by Gram's stain. The prevalence of bacterial vaginosis was 47% in the HIV-positive women compared with 44% in the HIV-negative women; this difference was not statistically significant (p = 0.36). After adjustment for other covariates, HIV-positive women were more likely than HIV-negative women to have bacterial vaginosis (odds ratio (OR) 1.31; 95% confidence interval (CI) 1.01-1.70) by Gram's stain but not by clinical criteria (OR 1.16; CI 0.87-1.55). Among HIV-positive women, use of antiretroviral drugs was associated with a lower prevalence of bacterial vaginosis (adjusted OR 0.54; Cl 0.38-0.77). CONCLUSIONS: In this cross-sectional analysis of high-risk US women, HIV infection was positively correlated with bacterial vaginosis diagnosed by Gram's stain.

AIDS-Related Opportunistic Infections↗
PubMed2000

Effect of HIV infection on menstrual cycle length.

HIV serostatus and menstrual function were examined using prospectively collected menstrual data from 802 HIV-seropositive and 273 HIV-seronegative women, ages 20 to 44, enrolled in two cohort studies of HIV infection in North American women. The associations between HIV serostatus and the probabilities of having a cycle lasting >40 days (n = 541 cycles), >90 days (n = 67 cycles), <18 days (n = 316 cycles) and mean length and variability of 18 to 40 day cycles (n = 3,634) were assessed. After adjustment for demographic characteristics, body mass index, and substance use, seropositivity increased the odds of having a very short cycle (< 18 days, odds ratio [OR], 1.45; 95% confidence interval [CI], 1.00-2.11) and a very long cycle (>90 days, OR, 1.32; 95% CI, 0.68-2.58) slightly, although the latter CIs include one. Seropositivity did not increase the odds of having a moderately long cycle (>40 days, OR, 1.14) or affect mean cycle length or variability (beta, 0.30 +/- 0.20; between-woman standard deviation [SD], 2.2 days [HIV-seronegative] and 1.9 days [HIV-seropositive]; within-woman SD, 3.5 days for both). Although seropositivity may slightly increase the probability of very short cycles, HIV serostatus has little overall effect on amenorrhea, menstrual cycle length, or variability. Among HIV-seropositive women, higher viral loads and lower CD4+ counts were associated with increased cycle variability and polymenorrhea.

Adult↗
PubMed2000

The carboxyl terminus of v-Abl protein can augment SH2 domain function.

Abelson murine leukemia virus (Ab-MLV) transforms NIH 3T3 and pre-B cells via expression of the v-Abl tyrosine kinase. Although the enzymatic activity of this molecule is absolutely required for transformation, other regions of the protein are also important for this response. Among these are the SH2 domain, involved in phosphotyrosine-dependent protein-protein interactions, and the long carboxyl terminus, which plays an important role in transformation of hematopoietic cells. Important signals are sent from each of these regions, and transformation is most likely orchestrated by the concerted action of these different parts of the protein. To explore this idea, we compared the ability of the v-Src SH2 domain to substitute for that of v-Abl in the full-length P120 v-Abl protein and in P70 v-Abl, a protein that lacks the carboxyl terminus characteristic of Abl family members. Ab-MLV strains expressing P70/S2 failed to transform NIH 3T3 cells and demonstrated a greatly reduced capacity to mediate signaling events associated with the Ras-dependent mitogen-activated protein (MAP) kinase pathway. In contrast, Ab-MLV strains expressing P120/S2 were indistinguishable from P120 with respect to these features. Analyses of additional mutants demonstrated that the last 162 amino acids of the carboxyl terminus were sufficient to restore transformation. These data demonstrate that an SH2 domain with v-Abl substrate specificity is required for NIH 3T3 transformation in the absence of the carboxyl terminus and suggest that cooperativity between the extreme carboxyl terminus and the SH2 domain facilitates the transmission of transforming signals via the MAP kinase pathway.

3T3 Cells↗
PubMed1999

Productive infection of double-negative T cells with HIV in vivo.

HIV induces CD4 down-regulation from the surface of infected cells by several independent mechanisms, suggesting an important biological role for this phenomenon. In vitro CD4 down-regulation generates T cells with a double-negative (DN) CD4(-)CD8(-) T cell receptor-alphabeta(+) phenotype. However, evidence that this down-regulation occurs in vivo in HIV-infected subjects is lacking, and viral load or viral production assays invariably focus on CD4(+) T cells. We show here that HIV infection can often be detected in sorted DN cells from peripheral blood and lymph nodes, even when plasma viral load is undetectable. DN T cells infected with HIV represented up to 20% of the cellular viral load in T cells, as determined by DNA PCR. In patients on successful highly active antiretroviral therapy, the viral load decreased in the plasma in CD4(+) and in DN T cells, suggesting that infected DN cells, like CD4(+) cells, contribute to viral production and are sensitive to highly active antiretroviral therapy. Indeed, HIV unspliced and multispliced RNAs were often detectable in DN T cells in spite of the small size of this subset. Infectious virus from DN T cells was transmitted efficiently in coculture experiments with uninfected T cell lymphoblasts, even when viral DNA in the DN cells was barely detectable. We conclude that a discrete population of infected DN T cells exists in HIV-positive subjects, even when the plasma viral load is undetectable. These cells may represent an important source of infectious virus.

Adult↗
PubMed1999

Prevalence of lower genital tract infections among human immunodeficiency virus (HIV)-seropositive and high-risk HIV-seronegative women. HIV Epidemiology Research Study Group.

This study was undertaken to assess whether the prevalence of lower genital tract infections among human immunodeficiency virus (HIV)-seropositive women was higher than among high-risk HIV-seronegative women at their baseline visit for the HIV Epidemiology Research Study. Results were available for 851 HIV-seropositive and 434 HIV-seronegative women. Human papilloma virus (HPV) infection was more prevalent among HIV-seropositive women (64% vs. 28%). Bacterial vaginosis was common (35% vs. 33%), followed by trichomoniasis (12% vs. 10%), syphilis (8% vs. 6%), Chlamydia trachomatis infection (4% vs. 5%), candidal vaginitis (3% vs. 2%), and Neisseria gonorrhoeae infection (0.8% vs. 0.3%). Alcohol use (odds ratio [OR], 1.8; 95% confidence interval [CI], 1. 3-2.4) and smoking (OR, 1.8; 95% CI, 1.3-2.5) were associated with bacterial vaginosis. Bacterial vaginosis (OR, 2.3; 95% CI, 1.5-3.4), trichomoniasis (OR, 2.3; 95% CI, 1.1-4.7), and syphilis (OR, 3.1; 95% CI, 1.3-7.4) were found to be more prevalent among black women. Our study showed no statistically significant difference in the prevalence of lower genital tract infections except for HPV between HIV-infected and demographically and behaviorally similar HIV-uninfected high-risk women.

Adult↗
PubMed1999

Metabolic control of peroxisome abundance.

Zellweger syndrome and related disorders represent a group of lethal, genetically heterogeneous diseases. These peroxisome biogenesis disorders (PBDs) are characterized by defective peroxisomal matrix protein import and comprise at least 10 complementation groups. The genes defective in seven of these groups and more than 90% of PBD patients are now known. Here we examine the distribution of peroxisomal membrane proteins in fibroblasts from PBD patients representing the seven complementation groups for which the mutant gene is known. Peroxisomes were detected in all PBD cells, indicating that the ability to form a minimal peroxisomal structure is not blocked in these mutants. We also observed that peroxisome abundance was reduced fivefold in PBD cells that are defective in the PEX1, PEX5, PEX12, PEX6, PEX10, and PEX2 genes. These cell lines all display a defect in the import of proteins with the type-1 peroxisomal targeting signal (PTS1). In contrast, peroxisome abundance was unaffected in cells that are mutated in PEX7 and are defective only in the import of proteins with the type-2 peroxisomal targeting signal. Interestingly, a fivefold reduction in peroxisome abundance was also observed for cells lacking either of two PTS1-targeted peroxisomal beta-oxidation enzymes, acyl-CoA oxidase and 2-enoyl-CoA hydratase/D-3-hydroxyacyl-CoA dehydrogenase. These results indicate that reduced peroxisome abundance in PBD cells may be caused by their inability to import these PTS1-containing enzymes. Furthermore, the fact that peroxisome abundance is influenced by peroxisomal 105-oxidation activities suggests that there may be metabolic control of peroxisome abundance.

Cells, Cultured↗
PubMed1999

Restoration of immunity with interleukin-2 therapy.

HIV replication can now be effectively suppressed using antiretroviral combination regimens. The search continues, however, for ways to restore the immune response and eliminate reservoirs of latent infection. Interleukin-2 (IL-2) may augment the immune response in HIV-infected persons. This article discusses the rationale for using IL-2 in those with HIV disease and reviews key trials of IL-2 treatment regimens.

Antiretroviral Therapy, Highly Active↗
PubMed1998

Mucosal candidal colonization and candidiasis in women with or at risk for human immunodeficiency virus infection. HIV Epidemiology Research Study (HERS) Group.

The epidemiology of mucosal candidal colonization and candidiasis was studied in a multicenter cohort of 871 human immunodeficiency virus (HIV)-seropositive and 439 demographically and behaviorally similar HIV-seronegative women. Cross-sectional analyses at baseline revealed that oropharyngeal colonization with Candida species was more prevalent among seropositive women and among women reporting recent cigarette smoking and injection drug use. Oropharyngeal candidiasis was also more prevalent among seropositive women. Both oropharyngeal colonization and candidiasis were significantly associated with a lower median CD4 lymphocyte count among seropositive women. Vaginal candidal colonization was more prevalent among seropositive women and among those reporting recent injection drug use and current insulin or oral antihyperglycemic therapy. Vaginal candidiasis was equally likely to be diagnosed in seropositive and seronegative women and was not significantly related to recent sexual contact. Neither vaginal colonization nor candidiasis was significantly related to a lower median CD4 lymphocyte count among seropositive women. Baseline evaluation indicated differences in the epidemiology of oropharyngeal and vaginal candidal colonization and candidiasis in HIV-seropositive women and suggested possible variation in pathogenesis of candidal infection at these two mucosal sites.

AIDS-Related Opportunistic Infections↗
PubMed1998

High-dose multimodality therapy with autologous stem-cell support for stage IIIB breast carcinoma.

PURPOSE: Women with locally unresectable and inflammatory breast carcinoma (IBC) have an approximately 30% 5-year disease-free survival (DFS) rate with conventional multimodality therapy. A short but dose-intensive multimodality phase II trial was designed in an attempt to improve outcome in stage IIIB disease. Mastectomy was performed after high-dose therapy to evaluate pathologic response to treatment. METHODS: Women with newly diagnosed disease received four 2-week cycles of doxorubicin 90 mg/m2 with granulocyte colony-stimulating factor (G-CSF), followed by cyclophosphamide 6,000 mg/m2, thiotepa 500 mg/m2, and carboplatin 800 mg/m2 (CTCb) with marrow and peripheral-blood progenitor cell (PBPC) support. Local therapy consisted of mastectomy and radiotherapy. Tamoxifen (5 years) was begun if the patient was estrogen receptor-positive (ER+). RESULTS: Fifty women (46 stage IIIB [91% IBC], four stage IIIA) entered the study and 47 are assessable. Ten had mastectomy before any systemic therapy (seven with pathologic IBC, three with residual tumor after mastectomy). Eighty percent received full-dose doxorubicin with 60% on schedule. Clinical response rates to induction were 15% complete response (CR), 5% very good partial response (VGPR), 59% partial response (PR), and 21% minor response (MR)/stable disease (SD). Mastectomy after CTCb in 37 patients showed a 14% pathologic CR rate, 29% microscopic foci in breast and/or axilla, and 57% gross tumor. Fifteen (32%) patients have relapsed (median, 17 months post-CTCb). The 30-month DFS is estimated at 64%. For those in pathologic CR, with microscopic, or with gross disease remaining after CTCb, the 30-month DFS is estimated at 100%, 70%, and 38%, respectively. Those with zero, one to three, or > or = four positive nodes at axillary dissection had a median DFS of 31, 18, and 13 months, respectively. CONCLUSION: This short but dose-intensive multimodality approach for stage IIIB breast carcinoma is feasible with encouraging results to date.

Adult↗
PubMed1998

Dose escalation of the hypoxic cell sensitizer etanidazole combined with ifosfamide, carboplatin, etoposide, and autologous hematopoietic stem cell support.

Multiple mechanisms of drug resistance contribute to treatment failure. Although high-dose therapy attempts to overwhelm these defenses pharmacologically, this approach is only successful in a fraction of treated patients. Many drug resistance mechanisms are shared between malignant and normal cells, but the expression of various drug resistance mechanisms associated with hypoxia is largely confined to tumor tissue. Thus, reversal of this mechanism is likely to provide a therapeutic advantage to the host. This study was designed to define the dose-limiting toxicities and maximum tolerated dose of etanidazole when it is given concurrently with high-dose ifosfamide, carboplatin, and etoposide (ICE), with hematopoietic stem cell support. The maximum tolerated doses of high-dose ICE were administered concurrently with dose escalations of etanidazole, a hypoxic cell sensitizer. All agents were given by 96-h continuous i.v. infusion beginning on day -7. Mesna uroprotection was provided. Autologous marrow and cytokine mobilized peripheral blood progenitor cells were reinfused on day 0. Granulocyte colony-stimulating factor was administered following reinfusion until the granulocytes recovered to > 1000/microliter. Fifty-five adults with advanced malignancies were enrolled in cohorts of five to nine patients. Four dose levels of etanidazole between 3 and 5.5 g/m2/day (12, 16, 20, and 22 g/m2 total doses) and two doses of carboplatin (1600 and 1800 mg/m2 total doses) were evaluated. Seven patients died of organ toxicity (13%); two each from veno-occlusive disease of liver and sepsis; and one each from sudden death, renal failure, and refractory thrombocytopenic hemorrhage. Five deaths occurred at the top dose level. One additional patient suffered a witnessed cardiorespiratory arrest from ventricular fibrillation and was resuscitated. Dose-dependent and largely reversible peripheral neuropathy was observed consisting of two syndromes: severe cramping myalgic/neuralgic pain, predominantly in stocking glove distribution, occurring between day -3 and day 0, and a sensory peripheral neuropathy with similar distribution peaking around day +60. The maximal achievable dose of etanidazole (16 g/m2 dose level) resulted in a mean serum level of 38 micrograms/ml (25-55 micrograms/ml). Etanidazole significantly enhanced host toxicity of high-dose ICE. Effective modulatory doses of etanidazole could not be given with acceptable toxicity using this schedule.

Adult↗
PubMed1997

Antiserum to activity-dependent neurotrophic factor produces neuronal cell death in CNS cultures: immunological and biological specificity.

Activity-dependent neurotrophic factor (ADNF) is a glia-derived protein that is neuroprotective at femtomolar concentrations. ADNF is released from astroglia after treatment with 0.1 nM vasoactive intestinal peptide (VIP). To further assess the biological role of ADNF, antiserum was produced following sequential injections of purified ADNF into mice. Anti-ADNF ascites fluid (1:10,000) decreased neuronal survival by 45-55% in comparison to untreated cultures or those treated with control ascites. The neuronal death after anti-ADNF treatment was observed in cultures derived from the spinal cord, hippocampus or cerebral cortex at similar IC50's. Using a terminal deoxynucleotidyl transferase in situ assay to estimate apoptosis in cerebral cortical cultures, anti-ADNF was shown to produce a 70% increase in the number of labeled cells in comparison to controls. In spinal cord cultures, anti-ADNF treatment produced a 20% decrease in choline acetyltransferase activity in comparison to controls. Neuronal cell death produced by the antiserum to ADNF was prevented in cultures co-treated with purified ADNF or ADNF-15, an active peptide derived from the parent ADNF. In vitro binding between the anti-ADNF and ADNF-15 was demonstrated with size exclusion chromatography. Comparative studies with other growth factors (insulin-like growth factor-1, platelet-derived growth factor, nerve growth factor, epidermal growth factor, ciliary neurotrophic growth factor, and neurotrophin-3) demonstrated that only ADNF prevented neuronal cell death associated with electrical blockade. These investigations indicated that an ADNF-like substance was present in cultures derived from multiple locations in the central nervous system and that ADNF-15 exhibited both neuroprotection and immunogenicity. ADNF appears to be both a regulator of activity-dependent neuronal survival and a neuroprotectant.

Amino Acid Sequence↗