PubMed Health⌕ Search

Biomedical subjects

I Anderson

Publications and source records attributed to I Anderson.

At least 37 records · Page 2Linked to original sources
PubMed2001

Gemcitabine and vinorelbine in patients with advanced lung cancer: preclinical studies and report of a phase I trial.

PURPOSE: This study was designed to assess the efficacy of gemcitabine plus vinorelbine using the mouse Lewis lung carcinoma model and to translate this regimen to a phase I clinical study of these two agents in patients with advanced lung cancer. MATERIALS AND METHODS: Using the mouse Lewis lung cancer model, employing growth delay and isobologram analysis, we demonstrated that gemcitabine, in combination with vinorelbine, produced additive activity with little increased toxicity over a wide range of doses. At the highest dose level studied, antagonism was observed. Based on these results, we initiated a phase IGemcitabine and vinorelbine in patients with advanced lung cancer: preclinical studies and report of a phase I trial study of this combination at the Dana Farber Cancer Institute (DFCI) in patients with untreated or once pretreated non-small-cell lung cancer (NSCLC) or once pretreated small-cell lung cancer (SCLC). Vinorelbine (given in an intravenous bolus) and gemcitabine (given in a 30-min infusion) were initially administered to patients at a dose of 15 mg/m2 and 500 mg/m2, respectively, on days 1, 8, and 15 of a 28-day cycle. Seven dose levels were subsequently explored over the course of the study. There was no intrapatient dose escalation. RESULTS: From November 1996 to March 1998, 40 patients were enrolled: 32 had NSCLC, 5 had SCLC and 3 had mixed disease (both SCLC and NSCLC). The patients were evenly divided by gender, the median age was 58 years (range 38 to 73 years), and the median ECOG performance status was 1 (range 0 to 2). All patients had normal renal and hepatic function and none had previously received gemcitabine or vinorelbine. Toxic reactions included mild to moderate fatigue, nausea, constipation, and, most significantly, neutropenia and thrombocytopenia. Phlebitis was a major problem when central venous lines were not used with 15% grade 1/2 events. The day-15 dose was held in 43% of patients at the expanded dose. No true maximum tolerated dose was reached after completion of seven dose levels. Dose level 4 (22.5 mg/m2 vinorelbine and 1,000 mg/m2 gemcitabine) was chosen for expansion and future study due to the potential increased ability of patients to receive the full doses on time. CONCLUSIONS: We conclude that this drug combination and dosage are feasible and have potential as either a front- or second-line chemotherapeutic regimen for advanced lung cancer, and phase II/III trials should be performed. However, hematologic toxicities, as found in this study, could probably be reduced with treatment on days 1 and 8 every 21 days, and current literature would suggest this to be the preferred schedule.

Adult↗
PubMed2001

Oxidative signalling and inflammatory pathways in Alzheimer's disease.

It is well established that inflammation and oxidative stress are key components of the pathology of Alzheimer's disease (AD), but how early in the pathological cascade these processes are involved or which specific molecular components are key, has not been fully elucidated. This paper describes the pharmacological approach to understand the molecular components of inflammation and oxidative stress on the activation of microglial cells and neuronal cell viability. We have shown that activation of microglia with the 42-amino-acid form of the beta-amyloid peptide (A beta 42) activates the production of cyclooxygenase-2, the inducible form of nitric oxide synthase and tumour necrosis factor-alpha and there appears to be little interactive feedback between these three mediators. Moreover, we explore the effects of a series of salen-manganese complexes, EUK-8, -134 and -189, which are known to possess both superoxide and catalase activity. These compounds are able to protect cells from insults produced by hydrogen peroxide or peroxynitrite. Moreover, EUK-134 was also able to limit the output of prostaglandin E2 from activated microglial cells. The mechanisms underlying these effects are discussed. Together, these data support a pivotal role for oxidative stress and inflammation as key mediators of the pathological cascade in AD and provide some ideas about possible therapeutic targets.

Alzheimer Disease↗
PubMed2001

Detection of immune system cells in paraffin wax-embedded ovine tissues.

This report describes a method (fixation, paraffin wax-embedding and immunolabelling) for the demonstration of several immune system cell epitopes (CD1, CD2, CD4, CD8, CD14, CD21, CD45R, WC-1, 28 kDa surface antigen, immunoglobulins and MHC II antigens) in ovine lymph nodes collected at necropsy. Cell surface epitopes considered to be sensitive to processing methods were successfully demonstrated by a procedure that included the use of a non-aldehyde-containing, zinc salts-based fixative, coupled with a sensitive system of immunolabelling. This novel method had the advantage of avoiding antigen-retrieval steps and of providing consistently good morphological definition.

Animals↗
PubMed2001

Self-assessed health among indigenous Australians: how valid is a global question?

OBJECTIVES: This study assessed the validity of a global measure of self-assessed health among Indigenous Australians. METHODS: Logistic regression was used to identify factors associated with self-assessed health in a nationally representative sample. RESULTS: Among 8782 adult respondents, poorer self-assessed health was strongly associated with several factors, including age, number of health conditions, and recent health actions. The association with health conditions was attenuated when the respondent's primary language was not English. CONCLUSIONS: Self-assessed health may be a valid measure among indigenous Australians whose primary language is English. However, although the measure draws on common experiences of health and illness, it may obscure differences in how people incorporate these experiences into social actions.

Adolescent↗
PubMed2001

The properties of hyaluronan and its role in wound healing.

Hyaluronan occurs naturally in the body. It appears to have an important role in wound healing and is essential to scarless healing in a fetus. Hyaluronan has now been developed as a wound dressing. This paper will examine the literature to assess the dressing's usefulness in difficult-to-heal, chronic wounds, which present a great challenge to tissue viability experts.

Adjuvants, Immunologic↗
PubMed2000

Estrogen receptor alpha interaction with estrogen response element half-sites from the rat prolactin gene.

Estrogen regulation of the rat prolactin gene requires sequences within the DNase I hypersensitive site II (HSII). We have used overexpressed mouse estrogen receptor alpha (ERalpha) protein to study interactions of ERalpha with an imperfect estrogen response element (ERE) and four ERE half-site sequences from HSII. We confirmed that ERalpha has higher affinity for ERE half-sites than for the imperfect ERE. As expected, the imperfect ERE formed a complex with ERalpha similar to that between mERalpha and a consensus ERE in gel shift assays. The ERalpha complex with half-sites, however, had faster mobility on a 4% polyacrylamide gel than the ERalpha complex with a consensus ERE, indicating that the complexes had different compositions. Ferguson analysis revealed that the ERalpha/half-site complex had a larger molecular weight and higher negative charge than the ERalpha/consensus ERE complex. Similar results were observed with purified human ERalpha, showing that the ERalpha/half-site complex contained only ERalpha and oligonucleotides. These results are best explained by a model in which a dimer of ERalpha is bound to two half-site oligonucleotides. We propose that two ERalpha dimers may interact with the four ERE half-sites in HSII to influence estrogen regulation of this gene.

Animals↗
PubMed2000

Intestinal failure after surgery for complicated radiation enteritis.

Between 1983 and 1997, a total of 16 patients were referred to a tertiary Intestinal Failure Unit (IFU) following surgery elsewhere for complications of radiation enteritis. Eleven were female with a mean age of 43 years (range 21-71 years) and the most common primary site of malignancy was genitourinary (n = 13). Patients had undergone an average of two laparotomies (range 1-7 laparotomies) for complications of radiation enteritis prior to transfer to the IFU. On admission, the principal problem in eight patients was persisting intestinal fistulation, four patients had continuing intestinal obstruction and four had the short bowel syndrome after extensive intestinal resection. Only one patient had evidence of residual malignancy; this patient with short bowel syndrome was allowed home without invasive therapy. Of the remaining 15 patients, 12 required an abdominal surgical procedure, while three were discharged without further surgery after training for home parenteral nutrition (HPN). Following abdominal surgery, five patients died in hospital, but the remaining seven patients went home alive--including two further patients on HPN. Overall, of the 15 patients referred with intestinal failure after surgery for complications of radiation enteritis and actively treated, one-third died in hospital and a further third required institution of HPN before being able to be discharged home.

Adult↗
PubMed1999

Simultaneous measurement of multiple mRNAs with a single control by quantitative competitive reverse transcriptase-polymerase chain reaction: glucose transporters Glut1 and Glut4.

Theoretical considerations for extending the application of quantitative competitive polymerase chain reaction (qc-PCR) to include the simultaneous measurement of multiple mRNAs, specifically the mammalian glucose transporters Glut1 and Glut4, are presented with experimental data in which the accuracy and flexibility of the system are examined. This method reliably measures changes in the initial concentration for each of three target DNA sequences. The reaction is not acutely sensitive to variations in either the primer sites or internal sequence, and although the initial concentrations of the target DNAs did affect the relative amplification efficiencies, the effect was limited and did not prohibit quantification. This PCR system was able to reliably detect differences as little as 50% in the initial concentration of the Glut1 target DNA sequence. Therefore, with the appropriate controls, PCR can be extended to include the simultaneous quantification of more than one target DNA with a single internal control.

Animals↗
PubMed1999

Report of the International Equine Gene Mapping Workshop: male linkage map.

The goal of the First International Equine Gene Mapping Workshop, held in 1995, was the construction of a low density, male linkage map for the horse. For this purpose, the International Horse Reference Family Panel (IHRFP) was established, consisting of 12 paternal half-sib families with 448 half-sib offspring provided by 10 laboratories. Blood samples were collected and DNA extracted in each laboratory and sent to the Lexington laboratory (KY, USA) for dispatch in aliquots to 14 typing laboratories. In total, 161 markers (144 microsatellites, seven blood groups and 10 proteins) were tested for all families for which the sire was heterozygous. Genealogies and typing data were sent for analysis to the INRA laboratory (Jouy-en-Josas, France) according to a specific format and entered into a database with input verification and output processes. Linkage analysis was performed with the CRIMAP program. Significant linkage was detected for 124 loci, of which 95 were unambiguously ordered using a multipoint analysis with an average spacing of 14.2 CM. These loci were distributed among 29 linkage groups. A more comprehensive analysis including synteny group data and FISH data suggested that 26 autosomes out of 31 are covered. The complete map spans 936 CM.

Animals↗
PubMed1999

Systematic review and guide to selection of selective serotonin reuptake inhibitors.

A meta-analysis of 20 short term comparative studies of 5 selective serotonin reuptake inhibitors (SSRIs; citalopram, fluoxetine, fluvoxamine, paroxetine and sertraline) has shown no difference in efficacy between individual compounds but a slower onset of action of fluoxetine. There were suggestions that fluoxetine caused more agitation, weight loss and dermatological reactions than the other SSRIs. More patients discontinued fluvoxamine and fewer patients stopped sertraline because of adverse effects than their comparator SSRIs. The most common adverse reactions to the SSRIs were gastrointestinal (especially nausea) and neuropsychiatric (particularly headache and tremor). Data from the Committee on Safety of Medicines showed more reports of suspected reactions (including discontinuation reactions) to paroxetine, and of gastrointestinal reactions to fluvoxamine and paroxetine, than the other SSRIs during their first 2 years of marketing. Prescription-event monitoring revealed a higher incidence of adverse events related to fluvoxamine than its comparators. There were higher incidences of gastrointestinal symptoms, malaise, sedation and tremor during treatment with fluvoxamine and of sedation, tremor, sweating, sexual dysfunction and discontinuation reactions with paroxetine. Fluoxetine was not associated with a higher incidence of suicidal, aggressive and related events than the other SSRIs. Patients have survived large overdoses of each of the compounds, but concern has been expressed over 6 fatalities following overdoses of citalopram. Drug interactions mediated by cytochrome P450 enzymes are theoretically less likely to occur during treatment with citalopram and sertraline, but there is a sparsity of clinical data to support this. Methodological difficulties and price changes do not allow choice for recommendations on the choice of SSRI based on pharmacoeconomic data. Taking into account the strengths and weaknesses of the methods used to compare drugs, guidelines to the selection of individual SSRIs in clinical practice are proposed. Citalopram should be avoided in patients likely to take overdoses. Fluoxetine may not be the drug of first choice for patients in whom a rapid antidepressant effect is important or for those who are agitated, but it may have advantages over other SSRIs in patients who are poorly compliant with treatment and those who have previously had troublesome discontinuation symptoms. Fluvoxamine, and possibly paroxetine, should not be used as first choice in patients especially prone to SSRI-related adverse reactions, while paroxetine should be avoided if previous discontinuation of treatment was troublesome. When in doubt about the risks of drug interactions, citalopram or sertraline should be considered given the lower theoretical risk of interactions.

Humans↗
PubMed1998

Estrogen receptor alpha requires no accessory factors for high-affinity binding to a consensus response element.

Estrogen receptor (ER) alpha is commonly thought to bind to a consensus estrogen response element (ERE) as a homodimer, but previous experiments have not ruled out the presence of other proteins in the ERalpha/ERE complex. To characterize this interaction in more detail, we overexpressed mouse (m) ERalpha in a baculovirus system, using the selective advantage of the apoptosis inhibitor p35. Recombinant mERalpha possesses the predicted molecular weight and binds 17beta-estradiol and an oligonucleotide containing a consensus vitellogenin ERE with high affinity. Over a wide concentration range of mERalpha protein (0.1-50 nM), only one complex was detected between mERalpha and vitellogenin ERE in gel shift assays. The ratio of E2:vitellogenin ERE bound by mERalpha was close to 2:1, and each complex contained only one ERE. The molecular weight of the complex was determined to be 160 000, very close to that predicted for two mERalpha proteins and one ERE oligonucleotide, therefore providing strong evidence that no other proteins were present. Recombinant mERalpha was purified such that it was the only protein observable by silver stain. Purified mERalpha and mERalpha in a nuclear extract behaved identically in Ferguson analysis, providing more evidence that only mERalpha was binding to the ERE. Purified mERalpha bound vitellogenin ERE with high affinity (Kd = 0. 92 +/- 0.20 nM), indicating that no other proteins are necessary for high-affinity mERalpha interaction with a consensus ERE. To determine whether ERalpha in an estrogen-responsive mammalian tissue behaves the same as the overexpressed mERalpha, we tested rat uterine cytosol by Ferguson analysis. ERalpha in rat uterine cytosol behaved identically to overexpressed mERalpha, suggesting that ERalpha in the uterine extract also binds to DNA predominantly as a homodimer with no additional proteins.

Animals↗
PubMed1998

A directly spliced exon 10-containing CD44 variant promotes the metastasis and homotypic aggregation of aggressive non-Hodgkin's lymphoma.

Variants of the CD44 cell-surface adhesion molecule include additional sequences encoded by combinations of exons from the membrane proximal domain (exons 6-14). Preliminary studies suggest that these additional variable membrane proximal sequences may alter the ligand specificity, glycosylation, and biologic function of CD44. In earlier studies, we found that primary extranodal and widely disseminated aggressive non-Hodgkin's lymphomas (NHLs) and normal activated B cells expressed a directly spliced exon 10-containing variant (CD44ex10), whereas normal resting B cells expressed larger exon 10-containing variants (CD44ex10-14 and CD44ex7-14). To obtain additional information regarding the function of exon 10-containing CD44 variants in aggressive NHL, we generated aggressive NHL transfectants that expressed CD44ex10, CD44ex10-14, CD44ex7-14, the standard CD44 isoform (CD44H), or vector alone, and evaluated the local tumorogenicity, aggregation, and metastatic potential of these transfectants. CD44ex10 aggressive NHL transfectants were more likely to cause local tumor formation in nude mice than transfectants expressing the larger exon 10-containing variants, CD44H, or vector alone. In addition, cell suspensions derived from CD44ex10 local tumors exhibited far greater homotypic aggregation than those obtained from other CD44 or vector-only local tumors. In nude mice that received CD44ex10 transfectants, distant metastases were also significantly more likely to develop than in animals that were given either the CD44ex10-14, CD44ex7-14, CD44H, or vector-only transfectants. These data provide the first evidence that the directly spliced exon 10-containing CD44 variant (CD44ex10) has a unique biologic function in aggressive NHL.

Alternative Splicing↗