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J Carmichael

Publications and source records attributed to J Carmichael.

At least 37 records · Page 2Linked to original sources

Bacterial and yeast chaperones reduce both aggregate formation and cell death in mammalian cell models of Huntington's disease.

Huntington's disease (HD) is an autosomal dominant neurodegenerative condition caused by expansions of more than 35 uninterrupted CAG repeats in exon 1 of the huntingtin gene. The CAG repeats in HD and the other seven known diseases caused by CAG codon expansions are translated into long polyglutamine tracts that confer a deleterious gain of function on the mutant proteins. Intraneuronal inclusions comprising aggregates of the relevant mutant proteins are found in the brains of patients with HD and related diseases. It is crucial to determine whether the formation of inclusions is directly pathogenic, because a number of studies have suggested that aggregates may be epiphenomena or even protective. Here, we show that fragments of the bacterial chaperone GroEL and the full-length yeast heat shock protein Hsp104 reduce both aggregate formation and cell death in mammalian cell models of HD, consistent with a causal link between aggregation and pathology.

Amino Acid Substitution↗

Microtubules regulate local Ca2+ spiking in secretory epithelial cells.

The role of the cytoskeleton in regulating Ca(2+) release has been explored in epithelial cells. Trains of local Ca(2+) spikes were elicited in pancreatic acinar cells by infusion of inositol trisphosphate through a whole cell patch pipette, and the Ca(2+)-dependent Cl(-) current spikes were recorded. The spikes were only transiently inhibited by cytochalasin B, an agent that acts on microfilaments. In contrast, nocodazole (5-100 micrometer), an agent that disrupts the microtubular network, dose-dependently reduced spike frequency and decreased spike amplitude leading to total blockade of the response. Consistent with an effect of microtubular disruption, colchicine also inhibited spiking but neither Me(2)SO nor beta-lumicolchicine, an inactive analogue of colchicine, had any effect. The microtubule-stabilizing agent, taxol, also inhibited spiking. The nocodazole effects were not due to complete loss of function of the Ca(2+) signaling apparatus, because supramaximal carbachol concentrations were still able to mobilize a Ca(2+) response. Finally, as visualized by 2-photon excitation microscopy of ER-Tracker, nocodazole promoted a loss of the endoplasmic reticulum in the secretory pole region. We conclude that microtubules specifically maintain localized Ca(2+) spikes at least in part because of the local positioning of the endoplasmic reticulum.

Animals↗

Randomized trial of paclitaxel plus supportive care versus supportive care for patients with advanced non-small-cell lung cancer.

BACKGROUND: In phase II trials, paclitaxel has been shown to have antitumor activity in patients with advanced non-small-cell lung cancer (NSCLC). However, the survival and quality-of-life (QOL) benefits of paclitaxel used as a single agent compared with supportive care alone have not been assessed in a randomized clinical trial. METHODS: A total of 157 patients with stage IIIB or IV NSCLC who had received no prior chemotherapy were randomly assigned to receive either best supportive care alone (78 patients) or paclitaxel plus supportive care (79 patients). Paclitaxel was administered as a 3-hour intravenous infusion every 3 weeks. Supportive care included palliative radiotherapy and supportive therapy with corticosteroids, antibiotics, analgesics, antiemetics, transfusions, and other symptomatic therapy as required. The primary end point of the study was survival. Time to disease progression, response rate, adverse events, and QOL were secondary end points. RESULTS: Pretreatment characteristics were evenly distributed between the two arms. Survival was statistically significantly better in the paclitaxel plus supportive care arm than in the supportive care alone arm (two-sided P =.037) (median survival = 6.8 months versus 4.8 months). Cox multivariate analysis showed paclitaxel plus supportive care to be statistically significantly associated with improved survival (two-sided P =.048). QOL was similar for both treatment arms, except for the functional activity score of the Rotterdam Symptom Checklist, where QOL data statistically significantly favored the paclitaxel plus supportive care arm (two-sided P =.043). CONCLUSION: The addition of paclitaxel to best supportive care significantly improved survival and time to disease progression compared with best supportive care in patients with advanced NSCLC and may improve some aspects of QOL.

Adult↗

Prostate adenocarcinoma cells release the novel proinflammatory polypeptide EMAP-II in response to stress.

The proinflammatory protein endothelial monocyte-activating polypeptide II (EMAP-II) was first detected in supernatants of murine tumor cells by virtue of its ability to stimulate endothelial-dependent coagulation in vitro. The purified protein has pleiotropic effects on endothelial cells, monocytes, and neutrophils; however, its function in vivo is unknown, and the mechanism whereby it is released from cells is poorly understood. We investigated the expression of EMAP-II in human prostate adenocarcinoma specimens by immunohistochemistry and in LNCaP and DU-145 human prostate adenocarcinoma cells by reverse transcription-PCR, flow cytometry, and Western blotting. We then examined the effects of chemical and physiological stress on release and processing of EMAP-II by LNCaP and DU-145 cells. These cells constitutively express a Mr 34,000 form of EMAP-II that is retained intracellularly. Exposure to agents that induce apoptosis or, in some cases, necrosis induces the release of the Mr 34,000 form and further processing to the Mr 27,000 and Mr 22,000 forms. Hypoxia, but not heat shock, is a potent inducer of release and processing of biologically active EMAP-II by LNCaP and DU-145 cells. We suggest that release of EMAP-II by prostate adenocarcinoma cells as a consequence of treatment with anticancer agents or as a result of constitutive hypoxia may potentiate the effects of those agents through the localized activation of host effector mechanisms.

Adenocarcinoma↗

Antitumor polycyclic acridines. 7. Synthesis and biological properties of DNA affinic tetra- and pentacyclic acridines.

New synthetic routes to a series of tetra- and pentacyclic acridines related in structure to marine natural products are reported. The novel water-soluble agent dihydroindolizino[7,6,5-kl]acridinium chloride 14 has inhibitory activity in a panel of non-small-cell lung and breast tumor cell lines exceeding that of m-AMSA. The salt inhibited the release of minicircle products of kDNA confirming that disorganization of topoisomerase II partly underlies the activity of the compound. COMPARE analysis of the NCI mean graph profile of compound 14 at the GI(50) level corroborates this conclusion with Pearson correlation coefficients (>0.6) to clinical agents of the topoisomerase II class: however, this correlation was not seen at the LC(50) level. The inhibitory action of 14 on Saccharomyces cerevisiae transfected with human topoisomerase II isoforms showed a 3-fold selectivity against the IIalpha isoform over the IIbeta isoform. Unlike m-AMSA, 14 is not susceptible to P-glycoprotein-mediated drug efflux and retains activity in lung cells with derived resistance to the topoisomerase II inhibitor etoposide.

Acridines↗

Irinotecan combined with fluorouracil compared with fluorouracil alone as first-line treatment for metastatic colorectal cancer: a multicentre randomised trial.

BACKGROUND: Irinotecan is active against colorectal cancer in patients whose disease is refractory to fluorouracil. We investigated the efficacy of these two agents combined for first-line treatment of metastatic colorectal cancer. METHODS: 387 patients previously untreated with chemotherapy (other than adjuvant) for advanced colorectal cancer were randomly assigned open-label irinotecan plus fluorouracil and calcium folinate (irinotecan group, n=199) or fluorouracil and calcium folinate alone (no-irinotecan group, n=188). Infusion schedules were once weekly or every 2 weeks, and were chosen by each centre. We assessed response rates and time to progression, and also response duration, survival, and quality of life. Analyses were done on the intention-to-treat population and on evaluable patients. FINDINGS: The response rate was significantly higher in patients in the irinotecan group than in those in the no-irinotecan group (49 vs 31%, p<0.001 for evaluable patients, 35 vs 22%, p<0.005 by intention to treat). Time to progression was significantly longer in the irinotecan group than in the no-irinotecan group (median 6.7 vs 4.4 months, p<0.001), and overall survival was higher (median 17.4 vs 14.1 months, p=0.031). Some grade 3 and 4 toxic effects were significantly more frequent in the irinotecan group than in the no-irinotecan group, but effects were predictible, reversible, non-cumulative, and manageable. INTERPRETATION: Irinotecan combined with fluorouracil and calcium folinate was well-tolerated and increased response rate, time to progression, and survival, with a later deterioration in quality of life. This combination should be considered as a reference first-line treatment for metastatic colorectal cancer.

Adenocarcinoma↗

Effects of heat shock, heat shock protein 40 (HDJ-2), and proteasome inhibition on protein aggregation in cellular models of Huntington's disease.

Huntington's disease (HD), spinocerebellar ataxias types 1 and 3 (SCA1, SCA3), and spinobulbar muscular atrophy (SBMA) are caused by CAG/polyglutamine expansion mutations. A feature of these diseases is ubiquitinated intraneuronal inclusions derived from the mutant proteins, which colocalize with heat shock proteins (HSPs) in SCA1 and SBMA and proteasomal components in SCA1, SCA3, and SBMA. Previous studies suggested that HSPs might protect against inclusion formation, because overexpression of HDJ-2/HSDJ (a human HSP40 homologue) reduced ataxin-1 (SCA1) and androgen receptor (SBMA) aggregate formation in HeLa cells. We investigated these phenomena by transiently transfecting part of huntingtin exon 1 in COS-7, PC12, and SH-SY5Y cells. Inclusion formation was not seen with constructs expressing 23 glutamines but was repeat length and time dependent for mutant constructs with 43-74 repeats. HSP70, HSP40, the 20S proteasome and ubiquitin colocalized with inclusions. Treatment with heat shock and lactacystin, a proteasome inhibitor, increased the proportion of mutant huntingtin exon 1-expressing cells with inclusions. Thus, inclusion formation may be enhanced in polyglutamine diseases, if the pathological process results in proteasome inhibition or a heat-shock response. Overexpression of HDJ-2/HSDJ did not modify inclusion formation in PC12 and SH-SY5Y cells but increased inclusion formation in COS-7 cells. To our knowledge, this is the first report of an HSP increasing aggregation of an abnormally folded protein in mammalian cells and expands the current understanding of the roles of HDJ-2/HSDJ in protein folding.

Acetylcysteine↗

A multicentre phase II pilot study of epirubicin and Taxol (paclitaxel) in patients with advanced breast cancer.

Anthracyclines are the gold standard monotherapy for metastatic breast cancer. Higher response rates are seen with drug combinations, especially with newer agents such as taxanes. The purpose of this study was to evaluate the toxicity and activity of the combination of paclitaxel and epirubicin in patients with advanced breast cancer. Thirty-five women with locally advanced or metastatic breast cancer (first and second relapse) were treated with epirubicin 75 mg/m2 and paclitaxel 200 mg/m2 3-weekly. Six centres recruited 35 patients; 34 (97%) were assessable for response. Eighteen had undergone prior chemotherapy, including six (17%) with anthracycline-containing regimens. Grade 4 neutropenia was found in 33 patients (94%), which was of 4 days' average duration; however, infective complications were rare, with only nine cycles (6%) complicated by neutropenic sepsis. There were two sepsis-related deaths. Symptomatic cardiotoxicity was infrequent, although a >15% decline in cardiac function was recorded in five patients (14%). Grade 3 peripheral neuropathy occurred in three patients (9%). The overall response rate was 50% (95% confidence interval 33-67) (complete response 12%; partial response 38%), with a median duration of response of 31 weeks. The median time to progression was 27 weeks, with a median survival of 48 weeks. This regimen appears to be a relatively safe, tolerable and effective treatment for advanced breast cancer. A United Kingdom Co-ordinating Committee for Cancer Research Phase III trial (AB-01) comparing this combination of epirubicin and paclitaxel with cyclophosphamide and paclitaxel completed accrual in November 1999.

Adult↗

Gemcitabine plus best supportive care (BSC) vs BSC in inoperable non-small cell lung cancer--a randomized trial with quality of life as the primary outcome. UK NSCLC Gemcitabine Group. Non-Small Cell Lung Cancer.

Three hundred patients with symptomatic, locally advanced or metastatic NSCLC not requiring immediate radiotherapy were enrolled into this randomized multicentre trial comparing gemcitabine + BSC vs BSC alone. Patients allocated gemcitabine received 1000 mg/m2 on days 1, 8 and 15 of a 28-day cycle, for a maximum of six cycles. The main aim of this trial was to compare patient assessment of a predefined subset of commonly reported symptoms (SS14) from the EORTC QLQ-C30 and LC13 scales. The primary end-points were defined as (1) the percentage change in mean SS14 score between baseline and 2 months and (2) the proportion of patients with a marked (> or = 25%) improvement in SS14 score between baseline and 2 months sustained for > or =4 weeks. The secondary objectives were to compare treatments with respect to overall survival, and multidimensional QL parameters. The treatment groups were balanced with regard to age, gender, Karnofsky performance status (KPS) and disease stage (40% had metastatic disease). The percentage change in mean SS14 score from baseline to 2 months was a 10% decrease (i.e. improvement) for gemcitabine plus BSC and a 1% increase (i.e. deterioration) for BSC alone (P = 0.113, two-sample t-test). A sustained (> or = 4 weeks) improvement (> or =25%) on SS14 was recorded in a significantly higher proportion of gemcitabine + BSC patients (22%) than in BSC alone patients (9%) (P = 0.0014, Pearson's chi-squared test). The QLQ-C30 and L13 subscales showed greater improvement in the gemcitabine plus BSC arm (in 11 domains) than in the BSC arm (one symptom item). There was greater deterioration in the BSC alone arm (six domains/items) than in the gemcitabine + BSC arm (three QL domains). Tumour response occurred in 19% (95% CI 13-27) of gemcitabine patients. There was no difference in overall survival: median 5.7 months (95% CI 4.6-7.6) for gemcitabine + BSC patients and 5.9 months (95% CI 5.0-7.9) (log-rank, P = 0.84) for BSC patients, and 1 -year survival was 25% for gemcitabine + BSC and 22% for BSC. Overall, 74 (49%) gemcitabine + BSC patients and 119 (79%) BSC patients received palliative radiotherapy. The median time to radiotherapy was 29 weeks for gemcitabine + BSC patients and 3.8 weeks for BSC. Patients treated with gemcitabine + BSC reported better QL and reduced disease-related symptoms compared with those receiving BSC alone. These improvements in patient-assessed QL were significant in magnitude and were sustained.

Adult↗

An economic analysis of a randomized, controlled, multicenter study of clinical pharmacist interventions for high-risk veterans: the IMPROVE study. Impact of Managed Pharmaceutical Care Resource Utilization and Outcomes in Veterans Affairs Medical Centers.

STUDY OBJECTIVE: To determine if clinical pharmacists could affect economic resource use and humanistic outcomes in an ambulatory, high-risk population. DESIGN: Prospective, randomized, controlled study. SETTING: Nine Veterans Affairs medical centers. PATIENTS: Patients who were at high risk for medication-related problems. INTERVENTION: Patients were randomized to usual medical care with input from a clinical pharmacist (intervention group) or just usual medical care (control group). MEASUREMENTS AND MAIN RESULTS: Of 1,054 patients enrolled, 523 were randomized to the intervention group and 531 to the control group. The number of clinic visits increased in the intervention group (p=0.003), but there was no difference in clinic costs. Mean increases in total health care costs were $1,020 for the intervention group and $1,313 for the control group (p=0.06). CONCLUSION: Including the cost of pharmacist interventions, overall health care expenditures were similar for patients randomized to see a clinical pharmacist versus usual medical care.

Aged↗

Clinical and economic impact of ambulatory care clinical pharmacists in management of dyslipidemia in older adults: the IMPROVE study. Impact of Managed Pharmaceutical Care on Resource Utilization and Outcomes in Veterans Affairs Medical Centers.

We examined the impact of ambulatory care clinical pharmacist interventions on clinical and economic outcomes of 208 patients with dyslipidemia and 229 controls treated at nine Veterans Affairs medical centers. This was a randomized, controlled trial involving patients at high risk of drug-related problems. Only those with dyslipidemia are reported here. In addition to usual medical care, clinical pharmacists were responsible for providing pharmaceutical care for patients in the intervention group. The control group did not receive pharmaceutical care. Seventy-two percent of the intervention group and 70% of controls required secondary prevention according to the National Cholesterol Education Program guidelines. Significantly more patients in the intervention group had a fasting lipid profile compared with controls (p=0.021). The absolute change in total cholesterol (17.7 vs 7.4 mg/dl, p=0.028) and low-density lipoprotein (23.4 vs 12.8 mg/dl, p=0.042) was greater in the intervention than in the control group. There were no differences in patients achieving goal lipid values or in overall costs despite increased visits to pharmacists. Ambulatory care clinical pharmacists can significantly improve dyslipidemia in a practice setting designed to manage many medical and drug-related problems.

Aged↗

Types of interventions made by clinical pharmacists in the IMPROVE study. Impact of Managed Pharmaceutical Care on Resource Utilization and Outcomes in Veterans Affairs Medical Centers.

The purpose of this study was to describe and evaluate the activities and interventions provided by ambulatory care clinical pharmacists during the IMPROVE (Impact of Managed Pharmaceutical Care on Resource Utilization and Outcomes in Veterans Affairs Medical Centers) study. A total of 523 patients were randomized into the intervention arm at nine Veterans Affairs medical centers if they were considered to be at high risk for drug-related problems. Patients randomized to the control group had no interventions and they are not reported. Using a standard form, pharmacists were asked to document the length of visit, method of contact, medical conditions addressed, and drug-related problems addressed and resolved during each contact. Seventy-eight ambulatory care clinical pharmacists documented 1855 contacts over 12 months, an average of 3.54 +/- 2.31/patient. The length of visits was 15 minutes or more for 73% of contacts. In-person contacts accounted for 1421 visits (76.6%), with the remainder being telephone contacts. During each contact the average number of drug-related problems addressed and resolved were 1.64 +/- 1.16 and 1.14 +/- 0.98, respectively. More drug-related problems were addressed and resolved when visits were 15 minutes or longer (p=0.001) and when the contact was in person (p=0.001). These data may provide information to clinical pharmacists developing pharmacy-managed clinics for patients at high risk for drug-related problems. The information may be a benchmark for types of interventions that can be made, as well as the time commitments required to make them.

Aged↗

Phase I study of ONO-4007, a synthetic analogue of the lipid A moiety of bacterial lipopolysaccharide.

ONO-4007 is a synthetic analogue of the lipid A moiety of bacterial lipopolysaccharide, which exhibits antitumor activity by the induction of intratumoral tumor necrosis factor alpha, the potentiation of tumor-infiltrating macrophages, and the inhibition of angiogenesis. Interleukin (IL)-1 alpha, IL-6, and IL-12 induction by ONO-4007 activates cytotoxic natural killer cells to up-regulate IFN-gamma and nitric oxide synthase activity. ONO-4007 was given to 24 patients (13 males and 11 females; median age, 53 years) as a 30-min i.v. infusion on day 1, followed on day 15 by a first treatment cycle consisting of three weekly infusions at the same dose, followed by a rest period of 1 week. Cohorts of six patients received up to a maximum of four treatment cycles at increasing dose levels (75, 100, and 125 mg). The maximum tolerated dose was 125 mg, with grade 3 National Cancer Institute Common Toxicity Criteria toxicity (rigors with cyanosis) occurring in two of six patients at this dose level. An additional six patients were treated at 100 mg, the dose below the maximum tolerated dose. Other toxicities included grade 2 National Cancer Institute Common Toxicity Criteria myalgia, nausea, and hypotension. The pharmacokinetics of ONO-4007 appeared to be independent of dose and showed linearity with respect to time. ONO-4007 has a low systemic clearance (approximately 1.3 ml/min) and a small volume of distribution (5-8 liters) with a long t1/2 of 74-95 h. The administration of ONO-4007 was shown to result in a significant increase in circulating levels of tumor necrosis factor alpha and IL-6. No objective antitumor responses were observed. Seven patients maintained stable disease for at least two cycles, whereas five patients maintained stable disease for the full four-cycle duration of the study. Additional studies are required to determine the antitumor activity of ONO-4007.

Adult↗

A neoadjuvant clinical trial in colorectal cancer patients of the human anti-idiotypic antibody 105AD7, which mimics CD55.

Thirty-five patients received 105AD7 human anti-idiotype vaccination prior to surgery for colorectal carcinoma. Patients were immunized before and also received one to two immunizations after surgical resection of their colorectal cancer. The vaccine was well tolerated with no associated toxicity. Lymphocytic infiltration within the resected tumors was quantified by immunohistochemistry and image analysis. Enhanced infiltration of helper T cells (CD4) and natural killer (NK) cells (CD56) were observed in the tumors from immunized patients when compared with tumors from stage, grade, site, age, and sex matched unimmunized patients. NK activity was increased in the blood, peaking 7-10 days post immunization and then dropping rapidly and correlating with NK extravasation within the tumor. Comparison of the amino acid sequences of 105AD7 anti-idiotype and the antigen it mimics, CD55, has predicted that patients with HLA-DR1, HLA-DR3, and HLA-DR7 haplotypes should show helper T cell responses following 105AD7 vaccination. Eighty-three percent of patients expressing these haplotypes responded to 105AD7, whereas 88% of patients who failed to express these haplotypes were nonresponders. With a median follow-up of 4 years (range, 2.5-6 years) 65% of patients remained disease free. This trial shows that 105AD7 stimulates antitumor inflammatory responses allowing extravasation within tumor deposits of both helper T cells and NK cells. This represents a way of evaluating immune responses in patients both within the blood and at the tumor site. The study confirms that immunization with a human anti-idiotypic antibody results in immune responses in 83% of patients with a permissive haplotype.

Antibodies, Anti-Idiotypic↗

Decay accelerating factor (CD55): a target for cancer vaccines?

The 791Tgp72 antigen has been used successfully as a target for tumor imaging and T-cell immunotherapy. We have characterized this antigen using the monoclonal antibody 791T/36 as a 72/66 kDa doublet. NH2-terminal protein sequencing of the two bands revealed identity with the complement regulatory protein CD55. Antibodies recognizing different domains of CD55 were also shown to bind to the purified 791Tgp72, although sequence analysis of the cDNA cloned from 791T tumor cells showed 100% homology with CD55 and transfection of the cDNA into antigen-negative CHO cells resulted in binding of 791T/36. This identifies the tumor antigen 791Tgp72 as CD55. This protein protects cells from complement attack; however, it can also transduce signals in lymphocytes and is a ligand for CD97, expressed by activated T cells. These results suggest that CD55 plays a role in signaling between the innate and adaptive immune responses. It is therefore a very intriguing target, because absence of the molecule makes the tumor cells susceptible to complement, whereas protective overexpression results in the antigen being a target for T-cell immunotherapy.

Amino Acid Sequence↗