Mapping QTL associated with resistance to Pseudomonas syringae pv. actinidiae in kiwifruit (Actinidia chinensis var. chinensis)

Pseudomonas syringae pv. actinidiae (Psa) is a bacterial pathogen of kiwifruit. This pathogen causes leaf-spotting, cane dieback, wilting, cankers (lesions), and in severe cases, plant death. Families of diploid A. chinensis seedlings grown in the field show a range of susceptibilities to the disease with up to 100% of seedlings in some families succumbing to Psa. But the effect of selection for field resistance to Psa on the alleles that remain in surviving seedlings has not been assessed. The objective of this work was to analyse, the effect of plant removal from Psa on the allele frequency of an incomplete-factorial-cross population. This population was founded using a range of genotypically distinct diploid A. chinensis var. chinensis parents to make 28 F1 families. However, because of the diversity of these families, low numbers of surviving individuals, and a lack of samples from dead individuals, standard QTL mapping approaches were unlikely to yield good results. Instead, a modified bulk segregant analysis (BSA) overcame these drawbacks while reducing the costs of sampling and sample processing, and the complexity of data analysis. Because the method was modified, part one of this work was used to determine the signal strength required for a QTL to be detected with BSA. Once QTL detection accuracy was known, part two of this work analysed the 28 families from the incomplete-factorial-cross population that had multiple individuals removed due to Psa infection. Each family was assigned to one of eight bulks based on a single parent that contributed to the families. DNA was extracted in bulk by grinding sampled leaf discs together before DNA extraction. Each sample bulk was compared against a bulk made up of WGS data from the parents contributing to the sample bulk. The deviation in allele frequency from the expected allele frequency within surviving populations using the modified BSA method was able to identify 11 QTLs for Psa that were present in at least two analyses. The identification of these Psa resistance QTL will enable marker development to selectively breed for resistance to Psa in future kiwifruit breeding programs.

The Relative Power of Structural Genomic Variation versus SNPs in Explaining the Quantitative Trait Growth in the Marine Teleost Chrysophrys auratus

Background: Genetic diversity provides the basic substrate for evolution. Genetic variation consists of changes ranging from single base pairs (single-nucleotide polymorphisms, or SNPs) to larger-scale structural variants, such as inversions, deletions, and duplications. SNPs have long been used as the general currency for investigations into how genetic diversity fuels evolution. However, structural variants can affect more base pairs in the genome than SNPs and can be responsible for adaptive phenotypes due to their impact on linkage and recombination. In this study, we investigate the first steps needed to explore the genetic basis of an economically important growth trait in the marine teleost finfish Chrysophrys auratus using both SNP and structural variant data. Specifically, we use feature selection methods in machine learning to explore the relative predictive power of both types of genetic variants in explaining growth and discuss the feature selection results of the evaluated methods. Methods: SNP and structural variant callers were used to generate catalogues of variant data from 32 individual fish at ages 1 and 3 years. Three feature selection algorithms (ReliefF, Chi-square, and a mutual-information-based method) were used to reduce the dataset by selecting the most informative features. Following this selection process, the subset of variants was used as features to classify fish into small, medium, or large size categories using KNN, naïve Bayes, random forest, and logistic regression. The top-scoring features in each feature selection method were subsequently mapped to annotated genomic regions in the zebrafish genome, and a permutation test was conducted to see if the number of mapped regions was greater than when random sampling was applied. Results: Without feature selection, the prediction accuracies ranged from 0 to 0.5 for both structural variants and SNPs. Following feature selection, the prediction accuracy increased only slightly to between 0 and 0.65 for structural variants and between 0 and 0.75 for SNPs. The highest prediction accuracy for the logistic regression was achieved for age 3 fish using SNPs, although generally predictions for age 1 and 3 fish were very similar (ranging from 0–0.65 for both SNPs and structural variants). The Chi-square feature selection of SNP data was the only method that had a significantly higher number of matches to annotated genomic regions of zebrafish than would be explained by chance alone. Conclusions: Predicting a complex polygenic trait such as growth using data collected from a low number of individuals remains challenging. While we demonstrate that both SNPs and structural variants provide important information to help understand the genetic basis of phenotypic traits such as fish growth, the full complexities that exist within a genome cannot be easily captured by classical machine learning techniques. When using high-dimensional data, feature selection shows some increase in the prediction accuracy of classification models and provides the potential to identify unknown genomic correlates with growth. Our results show that both SNPs and structural variants significantly impact growth, and we therefore recommend that researchers interested in the genotype–phenotype map should strive to go beyond SNPs and incorporate structural variants in their studies as well. We discuss how our machine learning models can be further expanded to serve as a test bed to inform evolutionary studies and the applied management of species.

Differential expression analyses reveal extensive transcriptional plasticity induced by temperature in New Zealand silver trevally (Pseudocaranx georgianus)

Ectotherm species, such as marine fishes, depend on environmental temperature to regulate their vital functions. In finfish aquaculture production, being able to predict physiological responses in growth and other economic traits to temperature is crucial to address challenges inherent in the selection of grow-out locations. This will become an even more significant issue under the various predicted future climate change scenarios. In this study, we used the marine teleost silver trevally (Pseudocaranx georgianus), a species currently being explored as a candidate for aquaculture in New Zealand, as a model to study plasticity in gene expression patterns and growth in response to different temperatures. Using a captive study population, temperature conditions were experimentally manipulated for 1 month to mimic seasonal extremes. Phenotypic differences in growth were measured in 400 individuals, and gene expression patterns of pituitary gland and liver were determined in a subset of 100 individuals. Results showed that growth increased 50% in the warmer compared with the colder condition, suggesting that temperature has a large impact on metabolic activities associated with growth. A total of 265,116,678 single-end RNA sequence reads were aligned to the trevally genome, and 28,416 transcript models were developed (27,887 of these had GenBank accessions, and 17,980 unique gene symbols). Further filtering reduced this set to 8597 gene models. 39 and 238 differentially expressed genes (DEGs) were found in the pituitary gland and the liver, respectively (|log2FC| > 0.26, p-value < 0.05). Of these, 6 DEGs showed a common expression pattern between both tissues, all involved in housekeeping functions. Temperature-modulated growth responses were linked to major pathways affecting metabolism, cell regulation and signalling, previously shown to be important for temperature tolerance in other fish species. An interesting finding of this study was that genes linked to the reproductive system were up-regulated in both tissues in the high treatment, indicating the onset of sexual maturation. Few studies have investigated the thermal plasticity of the gene expression in the main organs of the somatotropic axis simultaneously. Our findings indicate that trevally exhibit substantial growth differences and predictable plastic regulatory responses to different temperature conditions. We identified a set of genes that provide a list of candidates for further investigations for selective breeding objectives and how populations may adapt to increasing temperatures.

The genome of New Zealand trevally (Carangidae: Pseudocaranx georgianus) uncovers a XY sex determination locus

BACKGROUND

The genetic control of sex determination in teleost species is poorly understood. This is partly because of the diversity of mechanisms that determine sex in this large group of vertebrates, including constitutive genes linked to sex chromosomes, polygenic constitutive mechanisms, environmental factors, hermaphroditism, and unisexuality. Here we use a de novo genome assembly of New Zealand silver trevally (Pseudocaranx georgianus) together with sex-specific whole genome sequencing data to detect sexually divergent genomic regions, identify candidate genes and develop molecular makers.

RESULTS

The de novo assembly of an unsexed trevally (Trevally_v1) resulted in a final assembly of 579.4 Mb in length, with a N50 of 25.2 Mb. Of the assembled scaffolds, 24 were of chromosome scale, ranging from 11 to 31 Mb in length. A total of 28,416 genes were annotated after 12.8 % of the assembly was masked with repetitive elements. Whole genome re-sequencing of 13 wild sexed trevally (seven males and six females) identified two sexually divergent regions located on two scaffolds, including a 6 kb region at the proximal end of chromosome 21. Blast analyses revealed similarity between one region and the aromatase genes cyp19 (a1a/b) (E-value < 1.00E-25, identity > 78.8 %). Males contained higher numbers of heterozygous variants in both regions, while females showed regions of very low read-depth, indicative of male-specificity of this genomic region. Molecular markers were developed and subsequently tested on 96 histologically-sexed fish (42 males and 54 females). Three markers amplified in absolute correspondence with sex (positive in males, negative in females).

CONCLUSIONS

The higher number of heterozygous variants in males combined with the absence of these regions in females support a XY sex-determination model, indicating that the trevally_v1 genome assembly was developed from a male specimen. This sex system contrasts with the ZW sex-determination model documented in closely related carangid species. Our results indicate a sex-determining function of a cyp19a1a-like gene, suggesting the molecular pathway of sex determination is somewhat conserved in this family. The genomic resources developed here will facilitate future comparative work, and enable improved insights into the varied sex determination pathways in teleosts. The sex marker developed in this study will be a valuable resource for aquaculture selective breeding programmes, and for determining sex ratios in wild populations.

Construction of a high density genetic map for hexaploid kiwifruit (Actinidia chinensis var. deliciosa) using genotyping by sequencing

Commercially grown kiwifruit (genus Actinidia) are generally of two sub-species which have a base haploid genome of 29 chromosomes. The yellow-fleshed Actinidia chinensis var. chinensis, is either diploid (2n = 2x = 58) or tetraploid (2n = 4x = 116) and the green-fleshed cultivar A. chinensis var. deliciosa “Hayward,” is hexaploid (2n = 6x = 174). Advances in breeding green kiwifruit could be greatly sped up by the use of molecular resources for more efficient and faster selection, for example using marker-assisted selection (MAS). The key genetic marker that has been implemented for MAS in hexaploid kiwifruit is for gender testing. The limited marker-trait association has been reported for other polyploid kiwifruit for fruit and production traits. We have constructed a high-density linkage map for hexaploid green kiwifruit using genotyping-by-sequence (GBS). The linkage map obtained consists of 3686 and 3940 markers organized in 183 and 176 linkage groups for the female and male parents, respectively. Both parental linkage maps are co-linear with the A. chinensis “Red5” reference genome of kiwifruit. The linkage map was then used for quantitative trait locus (QTL) mapping, and successfully identified QTLs for king flower number, fruit number and weight, dry matter accumulation, and storage firmness. These are the first QTLs to be reported and discovered for complex traits in hexaploid kiwifruit.

A manually annotated Actinidia chinensis var. chinensis (kiwifruit) genome highlights the challenges associated with draft genomes and gene prediction in plants

Background

Most published genome sequences are drafts, and most are dominated by computational gene prediction. Draft genomes typically incorporate considerable sequence data that are not assigned to chromosomes, and predicted genes without quality confidence measures. The current Actinidia chinensis (kiwifruit) ‘Hongyang’ draft genome has 164 Mb of sequences unassigned to pseudo-chromosomes, and omissions have been identified in the gene models.

Results

A second genome of an A. chinensis (genotype Red5) was fully sequenced. This new sequence resulted in a 554.0 Mb assembly with all but 6 Mb assigned to pseudo-chromosomes. Pseudo-chromosomal comparisons showed a considerable number of translocation events have occurred following a whole genome duplication (WGD) event some consistent with centromeric Robertsonian-like translocations. RNA sequencing data from 12 tissues and ab initio analysis informed a genome-wide manual annotation, using the WebApollo tool. In total, 33,044 gene loci represented by 33,123 isoforms were identified, named and tagged for quality of evidential support. Of these 3114 (9.4%) were identical to a protein within ‘Hongyang’ The Kiwifruit Information Resource (KIR v2). Some proportion of the differences will be varietal polymorphisms. However, as most computationally predicted Red5 models required manual re-annotation this proportion is expected to be small. The quality of the new gene models was tested by fully sequencing 550 cloned ‘Hort16A’ cDNAs and comparing with the predicted protein models for Red5 and both the original ‘Hongyang’ assembly and the revised annotation from KIR v2. Only 48.9% and 63.5% of the cDNAs had a match with 90% identity or better to the original and revised ‘Hongyang’ annotation, respectively, compared with 90.9% to the Red5 models.

Conclusions

Our study highlights the need to take a cautious approach to draft genomes and computationally predicted genes. Our use of the manual annotation tool WebApollo facilitated manual checking and correction of gene models enabling improvement of computational prediction. This utility was especially relevant for certain types of gene families such as the EXPANSIN like genes. Finally, this high quality gene set will supply the kiwifruit and general plant community with a new tool for genomics and other comparative analysis.

Electronic supplementary material

The online version of this article (10.1186/s12864-018-4656-3) contains supplementary material, which is available to authorized users.

The value of local registry data for describing cervical cancer management and outcomes over three decades in Australia

Registry data on invasive cervical cancers (n = 1,274) from four major hospitals (1984-2012) were analysed to determine their value for informing local service delivery in Australia. The methodology comprised disease-specific survival analyses using Kaplan-Meier product-limit estimates and Cox proportional hazards models and treatment analyses using logistic regression. Five- and 10-year survivals were 72% and 68%, respectively, equating with relative survival estimates for Australia and the USA. Most common treatments were surgery and radiotherapy. Systemic therapies increased in recent years, generally with radiotherapy, but were less common for residents from less accessible areas. Surgery was more common for younger women and early-stage disease, and radiotherapy for older women and regional and more advanced disease. The proportion of glandular cancers increased in-step with national trends. Little evidence of variation in risk-adjusted survival presented over time or by Local Health District. The study illustrates the value of local registry data for describing local treatment and outcomes. They show the lower use of systemic therapies among residents of less accessible areas which warrants further investigation. Risk-adjusted treatment and outcomes did not vary by socio-economic status, suggesting equity in service delivery. These data are important for local evaluation and were not available from other sources.

U-2012: An improved Lowry protein assay, insensitive to sample color, offering reagent stability and enhanced sensitivity

Traditional colorimetric protein assays such as Biuret, Lowry, and modified Lowry (U-1988) are unsuitable for colored biological samples. Here we describe an improved Lowry protein assay (U-2012), which utilizes stable reagents and offers enhanced sensitivity over the U-1988 assay. U-2012 circumvents interference from colored pigments and other substances (for example sugars) bound to perchloric acid (PCA) precipitated proteins by hydrogen peroxide (H2O2) induced oxidation at 50°C. Unused hydrogen peroxide is neutralized with sodium pyruvate before protein estimation for a stable end color. The U-2012 assay is carried out on the PCA precipitated protein pellet after neutralization (with Na2CO3 plus NaOH), solubilization (in Triton-NaCl), decolorization (by H2O2) and pyruvate treatment. Protein contents in red wine and homogenates of beetroot and blueberry are calculated from standard curves established for various proteins and generated using a rectangular hyperbola with parameters estimated with Microsoft Excel's Solver add-in. The U-2012 protein assay represents an improvement over U-1988 and gives a more accurate estimation of protein content.

Double-blind, controlled phase II study of a 5-HT6 receptor antagonist, SB-742457, in Alzheimer's disease

BACKGROUND

This randomized, double-blind, placebo-controlled study investigated the efficacy and tolerability of the 5-HT6 receptor antagonist, SB-742457, in subjects with mild-to-moderate probable Alzheimer's disease (AD).

METHODS

Participating subjects had a Mini-Mental State Examination (MMSE) score of 12 to 26 after a 4-week, single-blind, placebo run-in phase, and were randomized (2:1:1:2) to receive placebo, SB-742457 5 mg, 15 mg, or 35 mg once daily for 24 weeks. Coprimary efficacy endpoints were the Clinician's Interview-Based Impression of Change with caregiver input (CIBIC+) score and change from baseline in Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) score at Week 24, in the intent-to-treat (ITT) population. A model-based design provided 90% power to detect a linear trend in treatment response across increasing doses and > or =90% power to compare SB-742457 35 mg with placebo.

RESULTS

371 subjects were randomized. In the ITT population (n=357), linear trend analysis at Week 24 suggested a dose response for CIBIC+ with a mean slope of -0.05 points/5-mg dose increase (95% confidence interval [CI]: -0.09, -0.01; p=0.016). The dose response slope for change from baseline in ADAS-Cog was -0.22 points/5-mg dose increase (95% CI: -0.45, 0.01; p=0.059). The adjusted mean treatment difference from placebo at Week 24 for SB-742457 35 mg (-0.31) was significant on CIBIC+ (95% CI: -0.62, -0.00; p=0.047) but non-significant on ADAS-Cog (-1.28 [95% CI: -2.96, 0.40]; p=0.135). Adverse events occurred in 24-37% in the SB-742457 groups vs 29% for placebo; 11-16% discontinued SB-742457 vs 15% for placebo.

COMMENTS

SB-742457 was generally safe and well tolerated and may be efficacious in AD.

Changes in colon gene expression associated with increased colon inflammation in interleukin-10 gene-deficient mice inoculated with Enterococcus species

Background

Inappropriate responses to normal intestinal bacteria may be involved in the development of Inflammatory Bowel Diseases (IBD, e.g. Crohn's Disease (CD), Ulcerative Colitis (UC)) and variations in the host genome may mediate this process. IL-10 gene-deficient (Il10^-/-) mice develop CD-like colitis mainly in the colon, in part due to inappropriate responses to normal intestinal bacteria including Enterococcus strains, and have therefore been used as an animal model of CD. Comprehensive characterization of changes in cecum gene expression levels associated with inflammation in the Il10^-/- mouse model has recently been reported. Our aim was to characterize changes in colonic gene expression levels in Il10^-/- and C57BL/6J (C57; control) mice resulting from oral bacterial inoculation with 12 Enterococcus faecalis and faecium (EF) strains isolated from calves or poultry, complex intestinal flora (CIF) collected from healthy control mice, or a mixture of the two (EF·CIF). We investigated two hypotheses: (1) that oral inoculation of Il10^-/- mice would result in greater and more consistent intestinal inflammation than that observed in Il10^-/- mice not receiving this inoculation, and (2) that this inflammation would be associated with changes in colon gene expression levels similar to those previously observed in human studies, and these mice would therefore be an appropriate model for human CD.

Results

At 12 weeks of age, total RNA extracted from intact colon was hybridized to Agilent 44 k mouse arrays. Differentially expressed genes were identified using linear models for microarray analysis (Bioconductor), and these genes were clustered using GeneSpring GX and Ingenuity Pathways Analysis software. Intestinal inflammation was increased in Il10^-/- mice as a result of inoculation, with the strongest effect being in the EF and EF·CIF groups. Genes differentially expressed in Il10^-/- mice as a result of EF or EF·CIF inoculation were associated with the following pathways: inflammatory disease (111 genes differentially expressed), immune response (209 genes), antigen presentation (11 genes, particularly major histocompatability complex Class II), fatty acid metabolism (30 genes) and detoxification (31 genes).

Conclusions

Our results suggest that colonic inflammation in Il10^-/- mice inoculated with solutions containing Enterococcus strains is associated with gene expression changes similar to those of human IBD, specifically CD, and that with the EF·CIF inoculum in particular this is an appropriate model to investigate food-gene interactions relevant to human CD.

Does retention of the ovaries improve long-term survival after hysterectomy? A gynecological oncological perspective

Ovarian cancer is, in most cases, a lethal disease as it is virtually impossible to diagnose at an early stage and almost impossible to treat successfully when detected at an advanced stage. In postmenopausal women, there is no prevention for ovarian cancer but oophorectomy. Therefore, from the gynecological oncological perspective, where benign gynecological pathology requires surgery in postmenopausal women, oophorectomy should be the preferred option.

A rapid transcriptional activation is induced by the dormancy-breaking chemical hydrogen cyanamide in kiwifruit (Actinidia deliciosa) buds

Budbreak in kiwifruit (Actinidia deliciosa) can be poor in locations that have warm winters with insufficient winter chilling. Kiwifruit vines are often treated with the dormancy-breaking chemical hydrogen cyanamide (HC) to increase and synchronize budbreak. This treatment also offers a tool to understand the processes involved in budbreak. A genomics approach is presented here to increase our understanding of budbreak in kiwifruit. Most genes identified following HC application appear to be associated with responses to stress, but a number of genes appear to be associated with the reactivation of growth. Three patterns of gene expression were identified: Profile 1, an HC-induced transient activation; Profile 2, an HC-induced transient activation followed by a growth-related activation; and Profile 3, HC- and growth-repressed. One group of genes that was rapidly up-regulated in response to HC was the glutathione S-transferase (GST) class of genes, which have been associated with stress and signalling. Previous budbreak studies, in three other species, also report up-regulated GST expression. Phylogenetic analysis of these GSTs showed that they clustered into two sub-clades, suggesting a strong correlation between their expression and budbreak across species.

Characterization of intestinal inflammation and identification of related gene expression changes in mdr1a(-/-) mice

Multidrug resistance targeted mutation (mdr1a (-/-) ) mice spontaneously develop intestinal inflammation. The aim of this study was to further characterize the intestinal inflammation in mdr1a (-/-) mice. Intestinal samples were collected to measure inflammation and gene expression changes over time. The first signs of inflammation occurred around 16 weeks of age and most mdr1a (-/-) mice developed inflammation between 16 and 27 weeks of age. The total histological injury score was the highest in the colon. The inflammatory lesions were transmural and discontinuous, revealing similarities to human inflammatory bowel diseases (IBD). Genes involved in inflammatory response pathways were up-regulated whereas genes involved in biotransformation and transport were down-regulated in colonic epithelial cell scrapings of inflamed mdra1 (-/-) mice at 25 weeks of age compared to non-inflamed FVB mice. These results show overlap to human IBD and strengthen the use of this in vivo model to study human IBD. The anti-inflammatory regenerating islet-derived genes were expressed at a lower level during inflammation initiation in non-inflamed colonic epithelial cell scrapings of mdr1a (-/-) mice at 12 weeks of age. This result suggests that an insufficiently suppressed immune response could be crucial to the initiation and development of intestinal inflammation in mdr1a (-/-) mice.

Conversion of MapMan to allow the analysis of transcript data from Solanaceous species: effects of genetic and environmental alterations in energy metabolism in the leaf

The tomato microarray TOM1 offers the possibility to monitor the levels of several thousand transcripts in parallel. The microelements represented on this tomato microarray have been putatively assigned to unigenes, and organised in functional classes using the MapMan ontology (Thimm et al., 2004. Plant J. 37: 914-939). This ontology was initially developed for use with the Arabidopsis ATH1 array, has a low level of redundancy, and can be combined with the MapMan software to provide a biologically structured overview of changes of transcripts, metabolites and enzyme activities. Use of this application is illustrated using three case studies with published or novel TOM1 array data sets for Solanaceous species. Comparison of previously reported data on transcript levels in potato leaves in the middle of the day and the middle of the night identified coordinated changes in the levels of transcripts of genes involved in various metabolic pathways and cellular events. Comparison with diurnal changes of gene expression in Arabidopsis revealed common features, illustrating how MapMan can be used to compare responses in different organisms. Comparison of transcript levels in new experiments performed on the leaves of the cultivated tomato S. lycopersicum and the wild relative S. pennellii revealed a general decrease of levels of transcripts of genes involved in terpene and, phenylpropanoid metabolism as well as chorismate biosynthesis in the crop compared to the wild relative. This matches the recently reported decrease of the levels of secondary metabolites in the latter. In the third case study, new expression array data for two genotypes deficient in TCA cycle enzymes is analysed to show that these genotypes have elevated levels of transcripts associated with photosynthesis. This in part explains the previously documented enhanced rates of photosynthesis in these genotypes. Since the Solanaceous MapMan is intended to be a community resource it will be regularly updated on improvements in tomato gene annotation and transcript profiling resources.

A phase I study of paclitaxel and altretamine as second-line therapy to cisplatin regimens for ovarian cancer

PURPOSE

The efficacy and pharmacokinetics of paclitaxel when combined with altretamine for ovarian cancer were studied.

METHODS

A group of 30 patients, whose only chemotherapy was one or more cisplatin-based non-paclitaxel-containing regimens and whose ovarian cancer failed to respond or had relapsed within 6 months of their last platinum regimen, received paclitaxel as a 3-h intravenous infusion and altretamine given orally in four divided doses daily for 14 days repeated every 28 days. Doses were escalated from paclitaxel/altretamine 135/150 mg/m2 to 250/300 mg/m2 in cohorts of three patients.

RESULTS

The dose-limiting toxicities at 250/300 mg/m2 were WHO grade 3 myalgias and arthralgias in two patients and grade 3 lethargy, stomach cramps, peripheral neuropathy and vomiting in single patients. Considering all dose levels in cycle 1, 16 patients had grade 3 or 4 neutropenia but there was only one episode of febrile neutropenia. Other grade 3 toxicities were vomiting in four patients, myalgias in three, peripheral neuropathy in two and lethargy in two. Grade 3 alopecia occurred in 23 patients. Three patients achieved a complete response and 12 achieved a partial response for an overall objective response rate of 50%. Responses occurred at all dose levels of 175/150 mg/m2 and higher. The median freedom from progression was 35 weeks, with a median survival of 55 weeks. Altretamine did not alter the pharmacokinetics of paclitaxel and there were no consistent differences in paclitaxel pharmacokinetic parameters or toxicities between course 1 and 2. No dose-response relationships were evident above paclitaxel/altretamine 175/150 mg/m2.

CONCLUSION

Paclitaxel and altretamine can be safely combined and with a high response rate in relapsed ovarian cancer, justifying further studies with this combination.

Reliability and sensitivity of joint space measurements in hand radiographs using computerized image analysis

OBJECTIVE

To establish the sensitivity and reliability of proximal interphalangeal (PIP) and metacarpophalangeal (MCP) mean joint space measurements using standard clinical radiographs of healthy subjects, in order to determine the limits at which a change in radiographic joint space could indicate a change in actual joint size.

METHODS

Repeat hand radiographs of healthy subjects were taken using standard techniques at 3-5 day intervals with the hands flat (5 posteroanterior radiographs in 8 subjects) or in 6 different flexed positions on a single occasion (8 subjects). The mean joint space was determined using custom soft ware and was validated manually. Measurement reproducibility within subjects, within films, and between hand positions was assessed by analysis of variance.

RESULTS

In repeat radiographs taken in the standard clinical position, the precision of individual join space measurements indicates that changes > 0.11 mm (approximately 7%) would represent an actual physical change in joint space width (with 95% probability). Averaging measurements across fingers for a single subject decreases the detectable change to 0.05 mm (approximately 3%). With increasing flexure, radiographic joint space tended to increase in MCP and decrease in PIP.

CONCLUSION

Mean finger joint space measured from standard clinical radiographs is a reliable and sensitive measurement in healthy subjects even with some change in hand position. Work is required to establish whether the joint space change measured from serial radiographs of patients with arthritis over a period of 6-12 mo exceeds the detectable limits of change derived in this study.

The clinical pharmacokinetics of a new pharmacokinetically enhanced formulation of amoxicillin/clavulanate

BACKGROUND

A new oral pharmacokinetically enhanced formulation of the broad-spectrum antibiotic amoxicillin/clavulanate has been developed to provide more effective therapy against resistant pathogens than is provided by currently available formulations by maintaining therapeutically useful plasma amoxicillin concentrations for a longer period after dosing.

OBJECTIVE

This study explored the pharmacokinetics of the new oral formulation of amoxicillin/clavulanate in healthy male and female subjects.

METHODS

A single oral dose of pharmacokinetically enhanced amoxicillin/clavulanate (2000/125 mg; 16:1 ratio) was administered to subjects at the start of a meal. After dosing, blood samples were collected at frequent intervals up to 12 hours, and plasma was assayed for amoxicillin and clavulanate concentrations using validated procedures. The new formulation consisted of 1 layer of immediate-release amoxicillin and clavulanate and another of sustained-release amoxicillin in a proportion such that for an amoxicillin minimum inhibitory concentration (MIC) of 4 microg/mL, the time above the MIC (T >MIC) would be approximately > or = 40% over a 12-hour dosing interval.

RESULTS

The study enrolled 24 and 31 healthy male and female subjects, respectively. Their mean age was 35 years (range, 18-58 years) and mean body weight was 69 kg (range, 51-86 kg). After the expected sharp peak in plasma amoxicillin concentration, there appeared to be a slower decline with the pharmacokinetically enhanced formulation than is usually seen with conventional formulations, and there was evidence of a second amoxicillin absorption phase. The mean T >MIC for an amoxicillin MIC of 4 microg/mL was 49.4% of a 12-hour dosing interval, a value that cannot be achieved with existing approved doses and formulations of amoxicillin/clavulanate. By 12 hours, plasma amoxicillin concentrations were very low (approximately 0.05 microg/mL), suggesting no expectation of notable dose-to-dose accumulation on repeat dosing with a BID regimen. The terminal half-lives of amoxicillin (1.27 hours) and clavulanate (1.03 hours) with the new formulation were similar to those of existing formulations of amoxicillin/clavulanate. No deaths or serious adverse events were reported.

CONCLUSIONS

The enhanced pharmacokinetic profile of amoxicillin/clavulanate seen in this study suggests that this formulation is likely to be highly effective for the oral treatment of infections caused by bacteria--including beta-lactamase-producing organisms--and strains with amoxicillin MICs < or = 4 microg/mL.

The morbidity of surgery and adjuvant radiotherapy in the management of endometrial carcinoma

A retrospective review of side effects and complications of treatment in 522 patients with endometrial cancer managed in a gyneoncology unit was conducted. This study evaluated 517 patients who underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH BSO). Lymphadendectomy or lymph node sampling was performed with the primary surgery in 264 and 41 cases, respectively. Postoperative radiotherapy was given as external beam or vault brachytherapy. Serious morbidity included lymphedema, hemorrhage, and vaginal stenosis. Lymphadenectomy was associated with lymphedema and lymphocyst formation in 11% of the cases. Vascular injury associated with lymphadenectomy occurred in 0.7% of the cases; however, this was satisfactorily managed through adequate surgical training and experience by staff within the unit. The incidence of vaginal stenosis (54.7%) following postoperative vault brachytherapy was a particular concern for clinical follow-up and sexual function. Although many women were not sexually active prior to treatment, those who were had high levels of sexual dysfunction, even when vaginal stenosis was not present.

Lack of effect of gemifloxacin on the steady-state pharmacokinetics of theophylline in healthy volunteers

Gemifloxacin is a novel fluoroquinolone, currently in development for the treatment of respiratory tract infections. This double-blind (with respect to gemifloxacin), randomized, crossover study investigated the possibility of pharmacokinetic interaction between gemifloxacin and theophylline. After a 4-8-day run-in phase to establish the dose of theophylline required to achieve a trough plasma concentration range of 8-15 mg/l, 15 healthy volunteers entered a randomized treatment phase. Volunteers then received oral theophylline, 300-400 mg twice daily, for 22 days. On days 5-11 and 16-22, they also received either placebo or gemifloxacin, 320 mg p.o. once daily, in a crossover fashion. Blood samples were collected up to 12 h after the morning dose of theophylline on days 11 and 22. Theophylline pharmacokinetics were not affected by the co-administration of gemifloxacin. The maximum plasma concentration (C(max)) for theophylline ranged from 8.12 to 17.71 mg/l and from 8. 79 to 16.35 mg/l during concomitant administration with gemifloxacin and placebo, respectively. The corresponding ranges of the area under the plasma concentration-time curve from time zero to the last quantifiable plasma concentration (AUC((0-12))) were 84.6-177.5 mg. h/l and 94.8-165.1 mg.h/l during gemifloxacin and placebo administration, respectively. The point estimates (90% confidence intervals) for dose-normalized AUC((0-12)) and C(max) (theophylline + gemifloxacin):(theophylline + placebo) were 0.99 (0.93, 1.05) and 1.02 (0.93, 1.11), respectively, which were entirely within the equivalence range (0.80, 1.25). The co-administration of gemifloxacin and theophylline was well tolerated, with no clinically significant changes seen in vital signs, 12-lead electrocardiogram readings or laboratory parameters. Adverse events were generally transient, mild to moderate in nature and similar during the gemifloxacin and placebo treatment periods. In conclusion, theophylline and gemifloxacin may be co-administered without any adjustment in theophylline dose.

Lack of effect of gemifloxacin on the steady-state pharmacodynamics of warfarin in healthy volunteers

Gemifloxacin is a novel fluoroquinolone with a broad spectrum of activity. This double-blind, randomized, parallel-group study was designed to demonstrate the lack of effect of steady-state concentrations of gemifloxacin on the pharmacodynamic effects of warfarin. Healthy male subjects received loading doses of warfarin on days 1 and 2. The warfarin dose was freely titrated until day 10, with the aim of achieving a stable international normalized ratio (INR) for prothrombin time within the range 1.3-1.8 by day 14. On days 14-24 the dose of warfarin was fixed. On days 18-24, subjects also received 320 mg of gemifloxacin or matched placebo, once daily. Thirty-five subjects entered into and completed the co-administration phase of the study. The mean (standard deviation) baseline INR (mean of days 16-18) and INR for day 24 for gemifloxacin plus warfarin were 1.52 (0.12) and 1.46 (0.15), respectively. Corresponding values for placebo plus warfarin were 1. 46 (0.11) and 1.42 (0.17). The point estimate (90% confidence interval) for the difference in day 24 INR, adjusted for baseline, between gemifloxacin and placebo was 0.02 (-0.08, 0.12), which translates to an INR (relative to placebo least squares mean of 1.43) of 1.02 (0.95, 1.09). The 90% confidence interval for the difference in INR between the gemifloxacin and placebo groups was completely contained within the 25% equivalence range. There were no changes of clinical significance in vital signs, 12-lead electrocardiogram readings or laboratory parameters for any subject during the co-administration phase of the study, and no adverse experiences relating to coagulation were reported during this period. It is concluded that the pharmacodynamic effects of warfarin are not affected by gemifloxacin, and therefore both drugs can be co-administered without dosage adjustment.

The effect of steady-state ropinirole on plasma concentrations of digoxin in patients with Parkinson's disease

AIMS

The aim of this single-blind study was to assess the effect of ropinirole, a novel treatment for Parkinson's disease, on the steady-state pharmacokinetics and safety of digoxin in 10 patients with Parkinson's disease.

METHODS

There were three parts to the study: digoxin once daily plus placebo three times daily for 1 week; digoxin once daily plus ropinirole three times daily for 6 weeks; and digoxin once daily plus placebo three times daily for 1 week. Serial blood samples were collected over 24 h at the end of each part of the study for pharmacokinetic assessment. Pre-dose blood samples were collected on specific days throughout the study to assess the attainment of steady-state plasma levels of digoxin. The primary endpoints were AUC(0, tau) and Cmax for digoxin.

RESULTS

There was a mean decrease of 10% in digoxin AUC (0, tau) (90% CI: 0.79, 1.01) and a 25% decrease in digoxin Cmax (90% CI: 0.58, 0.97) when ropinirole was co-administered, compared with digoxin alone Cmin plasma values for digoxin, however, were fairly constant throughout the study (point estimates 0.99, 95% CI: 0.85, 1.15). Changes in trough levels of digoxin are believed to be the most reliable way of assessing steady-state concentrations of digoxin, and therefore the clinical significance of an interaction. Changes in Cmax are too readily influenced by other factors.

CONCLUSIONS

These results therefore indicate that on pharmacokinetic grounds no dose adjustment is necessary for digoxin co-administered with ropinirole.

Patients' views of the care given by district nurses

Understanding the actions that make patients feel 'cared for' by district nurses can help staff tailor their work to meet patients' needs. Patients in one study felt that a trusting nurse/patient relationship is the basis of good nursing.

Evening dosing is associated with higher plasma concentrations of pranlukast, a leukotriene receptor antagonist, in healthy male volunteers

AIMS

To study the magnitude of differences in the pharmacokinetics of pranlukast, after morning and evening administration.

METHODS

Pranlukast (300 mg) was administered to 12 healthy male volunteers on two separate occasions, either in the morning or evening. Both doses were given 30 min after a standard high fat content meal. Blood samples were collected up to 18 h postdose. Plasma was assayed by high performance liquid chromatography. Standard pharmacokinetic and statistical analyses were performed.

RESULTS

Statistically significant (P < 0.05) increases were noted in AUC(o,t) (56%) and tmax (2.5 h) after evening administration. Cmax was 14% higher after evening dosing (95% C.I. 0.71-1.84).

CONCLUSIONS

Pranlukast bioavailability is apparently increased after evening dosing as compared with morning administration. Higher night-time and early morning plasma concentrations may confer additional therapeutic benefit at a time when asthmatics are at greatest risk of developing bronchospasm.

Cardiovascular pharmacology of aqueous extract of the leaves of Bridelia atroviridis Muell. Arg. (Euphorbiaceae) in the rat

Lyophilised decoction (10%) of the leaves of Bridelia atroviridis Muell. Arg. (Euphorbiaceae) was studied in the rat cardiovascular system. In vivo, the extract (15 and 30 mg/kg) caused a decrease of arterial pressure and a decrease of heart rate in an anaesthetized rat (ethylcarbamate 1.2 g/kg). If administrations of Bridelia were repeated (three times) a tachyphylaxie phenomena was observed. After administrations of adrenaline, noradrenaline, acethylcholine and isoprenaline the extract had no effect on the action of these neuromediators on blood pressure. In vitro the extract induced dose-dependent negative inotropic and chronotropic effects in isolated rat heart. It was ineffective in rat aorta preparations. Bridelia seemed to have a direct effect on rat heart. Hypotension is not due to an action on the vessels. The extract did not appear to interact with adrenergic nor cholinergic receptors. However, the extract was able to potentiate barium chloride induced contractions of rat aorta preparations. The extract might act through potential dependent calcium channels.

5-Hydroxytryptamine and beta-adrenoceptors in rat isolated atria

The positive chronotropic effect of a high concentration of 5-hydroxytryptamine (5-HT) in rat isolated atria results mainly from a tyramine-like mechanism and is linked to an increase in cAMP production by an indirect stimulation of beta-adrenoceptors. Using this preparation, we have compared the action of tyramine and 5-HT. The tyramine (0.15 microM)-induced increase in atrial rate was suppressed by atenolol (a beta 1-blocking drug) and by nadolol (a beta 1 beta 2-blocker), while the positive chronotropic effect of 5-HT was reduced by atenolol and suppressed by nadolol. The 5-HT-induced elevation in cAMP was unchanged in the presence of atenolol and abolished by nadolol. The involvement of beta 2-adrenoceptors in the effects of 5-HT could result from competition between 5-HT and noradrenaline at the beta 1-adrenoceptors that results in a fixation of noradrenaline on beta 2-adrenoceptors.

cGMP release in rat mesenteric arterioles and in conduit mesenteric artery

1. Relaxing factors were studied in two perfused preparations of the same vascular area in the rat: resistance mesenteric arterioles and conduit mesenteric artery. 2. In both preparations, an acetylcholine (ACh) infusion inhibited noradrenaline (NA) vasoconstrictor effects but at a ten-times greater concentration in conduit artery than in resistance arterioles. 3. Endothelium destruction with hypotonic Krebs solution did not change basal perfusion pressure, but increased NA responses and suppressed ACh inhibitory effects in arterioles and arteries. Likewise, L-NAME abolished the ACh effect in mesenteric arterioles but only reduced it in mesenteric artery. 4. Basal release of cyclic GMP was significantly greater in mesenteric artery than in resistance arterioles. By contrast, ACh-induced cGMP release was higher in mesenteric arterioles. Endothelium removal did not change basal release of cGMP in mesenteric arterioles but reduced it in mesenteric artery. 5. These results suggest that in basal conditions several relaxing factors are present in higher concentrations in conduit mesenteric artery than in resistance mesenteric arterioles. However, although it releases higher basal amount of cGMP, this vessel has a reduced role in vascular control than do smaller arteries.

Biochemical characterization of the mechanisms involved in the 5-hydroxytryptamine-induced increase in rat atrial rate

Several possible mechanisms for 5-hydroxytryptamine (5-HT)-induced tachycardia in rat have been suggested: an activation of 5-HT1C or 5-HT2 receptors, an indirect sympathomimetic effect or a mechanism independent of 5-HT2 receptor stimulation. The aim of this study was to investigate the involvement of these mechanisms in the 5-HT-induced increase in rat atrial rate using biochemical methods. Indeed, the 5-HT1C and 5-HT2 receptors are linked to phosphoinositide hydrolysis and the noradrenaline (NA) released by 5-HT can stimulate the beta 1-adrenergic receptors linked to adenylate cyclase stimulation. The effect of varying concentrations of 5-HT on inositol phospholipid hydrolysis and adenylate cyclase activity of the rat isolated atria were measured. 5-HT (2 microM) did not modify total inositol phosphate (IP) production, while 5-HT 10 and 50 microM increased it 2-fold. The 5-HT2 antagonist ketanserin (1 microM) abolished IP accumulation induced by 5-HT microM), which indicates that this accumulation is 5-HT2 and not 5-HT1C receptor-mediated. Moreover, cyclic AMP (cAMP) formation was enhanced by 5-HT (5, 10, 20 and 50 microM). When atria were incubated 10 min with the beta-adrenergic receptor antagonist nadolol (1 microM), the increase in the cAMP level induced by 5-HT, whatever its concentration (10, 20 or 50 microM), was inhibited. Treating rats with reserpine (2.5 mg/kg, i.p., 48 and 24 hr before experimentation), which caused NA depletion in the heart, seemed to reduce the stimulating effect of 5-HT 10 and 50 microM on adenylate cyclase activity. Thus, the 5-HT-induced increase in cAMP is indirectly due to the activation of the beta-adrenergic receptors by the NA released by 5-HT. It is concluded that 5-HT stimulates both phosphoinositide turnover and adenylate cyclase activity in the rat isolated atria by activation of 5-HT2 receptors and by an indirect sympathomimetic effect.

Effect of ketanserin on monoamines and neuropeptide Y in brain and peripheral tissues of normotensive (WKY) and spontaneously hypertensive (SHR) rats

The effect of one intraperitoneal (i.p.) injection of ketanserin (K) (20mg/kg) on the levels of monoamines and neuropeptide Y (NPY) in some central and peripheral tissues was examined in normotensive (WKY) and spontaneously hypertensive (SHR) rats. In WKY rats, K induced a depletion of norepinephrine (NE) in the hypothalamus, the medulla, the atria and the caudal artery together with a decrease in dopamine level (DA) in the hypothalamus and in serotonin level (5-hydroxytryptamine, 5-HT) in the medulla. The reduction reached 25% to 35%. In SHR, NE and DA levels in the hypothalamus, and NPY levels in the caudal artery were lower than in WKY, while NE was higher in the adrenals. After treatment with K, NE, 5-HT, 5-HIAA (5-hydroxyindoleacetic acid) and NPY in the medulla were increased by about 30% to 50% while NE in the caudal artery was reduced by about the same value as in WKY. These results indicate that K-induced release of monoamines is not linked to NPY release. Moreover, monoamine and NPY sensitivity to K differ in SHR and WKY rats.

Beta-core fragment of human chorionic gonadotropin in cervical intraepithelial neoplasia (CIN)

A low molecular weight glycoprotein immunologically identical with the beta-core fragment of hCG (beta C-hCG) has been described in invasive tumors of the genital tract, particularly carcinoma of the cervix. A previous report has also suggested increased urinary concentrations in subjects with cervical intraepithelial neoplasia (CIN). This prospective study of 107 patients with CIN was conducted to determine concentrations of beta C-hCG in the urine compared to a reference population without CIN. All subjects underwent a cervical smear and colposcopy, with biopsy when indicated. Between 11 and 18% of patients had urinary concentrations of beta C-hCG greater than the upper limit of the reference group and these results were confirmed when corrected for urinary creatinine concentration. A substantial number of subjects (19%) also had a positive result in a C-terminal immunoassay. It is concluded that preinvasive carcinoma of the cervix may secrete hCG or beta C-hCG in the earliest stages although measurement of beta C-hCG is unlikely to prove to be a valuable diagnostic marker in CIN.

Modulation of noradrenergic transmission in the rat isolated portal vein: Role of prejunctional α2-adrenoceptors and β-adrenoceptors

1. The effect of several adrenoceptor agonists and antagonists on the spontaneous and stimulus-evoked release of [3H]noradrenaline was studied in rat isolated portal vein. 2. Yohimbine (10(-6)M) increased the stimulus-evoked [3H]noradrenaline efflux. Adrenaline alone (3 x 10(-6)M) was without effect, while it increased the resting efflux when added together with yohimbine. 3. Propranolol alone was without effect on the release of [3H]noradrenaline. When added (2 x 10(-6)M) at the same time as yohimbine, it reduced the stimulation-induced 3H efflux. When added before adrenaline and yohimbine, propranolol (10(-5)M) reduced both spontaneous and stimulus-evoked release of [3H]noradrenaline. 4. The effect of several beta-blocking drugs was measured on the enhancing effect of yohimbine on the stimulation-evoked 3H efflux. The beta 1-adrenoceptor blocking drugs: atenolol (5 x 10(-6) and 10(-5) M), metoprolol (5 x 10(-6) and 10(-5) M), like the more selective bisoprolol (2 x 10(-6) and 4 x 10(-6) M) inhibited yohimbine activity. Likewise, propranolol (2 x 10(-6) and 5 x 10(-6)M) and the beta 2-adrenoceptor blocker ICI 118551 exhibited an antagonistic effect. 5. These results indicate the possibility for noradrenaline to activate presynaptic beta-adrenoceptors in rat portal vein. They show an interaction between the presynpatic alpha 2- and beta-adrenoceptor mediated systems in the release of noradrenaline. They suggest the presence and the activity of facilitatory beta 1-adrenoceptors.

Uptake of 5-hydroxytryptamine in rat isolated atria

1. The mode of 5-hydroxytryptamine (5-HT) uptake by the rat isolated atria was studied and compared to noradrenaline (NA) uptake. 2. Rat isolated atria were incubated with 14C-5-HT (46 microM) or 3H-NA 0.4 microM). After washing, the radioactivity fixed in atria was counted and the total NA, 5-HT and 5-hydroxyindol-3-acetic acid (5-HIAA) atria contents were measured by HPLC. 3. 14C-5-HT uptake was reduced in atria from 6-hydroxydopamine (100 mg/kg, i.p., 48 hr before experiments) or reserpine (2.5 mg/kg, i.p., 24 and 48 hr before experiments) pretreated rats. 4. The incubation of atria with 5-HT (50 microM) at the same time as 3H-NA reduced the 3H-NA value fixed. 5. Addition of desipramine (1 microM) or hydrocortisone (150 microM) before the incubation of atria with 14C-5-HT was without any effect on 14C-5-HT uptake. In contrast, fluvoxamine (1 microM) or indalpine (5 microM) caused a slight inhibition. 6. These data indicate that 5-HT is taken into the NA storage vesicles within the atria sympathetic nerves. This uptake does not use the NA carrier and involves partly the 5-HT carrier. An extraneuronal accumulation was noticed and a part of it is intracellular.

Effects of chloral, chloralose and pentobarbitone on monoamine and (neuropeptide Y) NPY levels in various tissues in the rat

Sampling of blood or tissues in experimental animals need frequently a general anesthesia. Some anesthetic agents are known to modify plasma levels of catecholamines; moreover NPY is co-released with noradrenaline or adrenaline under certain conditions. Thus, we investigated the effect of three general anesthetic agents, chloral, chloralose and pentobarbital (pentobarbitone) on the levels of monoamines and NPY in rat hypothalamus, medulla, atria and adrenals. Monoamines were analysed by high pressure liquid chromatography using an electrochemical detection and NPY was measured by radioimmunoassay (immunoradiometric assay, IRMA). Chloralose or pentobarbitone did not affect monoamine tissue levels. In contrast, chloral increased 5-hydroxyindolacetic acid and to a lesser extent serotonin levels in the hypothalamus. NPY tissue levels did not change whatever the anesthetic used. These results must be taken into account in pharmacological or toxicological studies which need the use of a general anesthesia.

Increased age and mortality associated with cervical carcinomas negative for human papillomavirus RNA

Attempts to relate presence and type of human papillomavirus in cervical carcinoma with prognosis have yielded conflicting results. To further investigate this relation, the association between survival of cervical cancer patients after diagnosis and the presence of human papillomavirus (HPV) RNA within the tumour was assessed retrospectively. Formalin-fixed biopsy specimens from 212 patients with cervical carcinoma who had been followed for up to 6 years were tested by in-situ hybridisation with 125I-labelled riboprobes. HPV-RNA-positive women were 11.9 years younger than HPV-negative women at diagnosis (p less than 0.001). Case-fatality rates from cervical cancer rose with absence of HPV RNA, age at diagnosis, or FIGO stage. Multivariate analysis confirmed that absence of detectable HPV RNA and advanced FIGO stage were independent risk factors. No differences in survival between HPV types 16, 18, 31, or 33 were seen. These observations suggest that cervical carcinoma patients fall into two groups--a younger, HPV-RNA-positive group, with a better prognosis, and an older, HPV-RNA-negative group with poorer prognosis. Treatment regimens for the two groups may need to differ.

Cardiovascular effects of intracerebroventricular injections of (+/-)-nebivolol and its enantiomers--a comparison with those of metoprolol in the rat

The cardiovascular effects of (+/-)-nebivolol, a potent beta 1-adrenoceptor antagonist, and its enantiomers, (+)-nebivolol (SRRR) and (-)-nebivolol (RSSS) in normotensive anaesthetized rats, have been investigated using metoprolol as a reference substance. The drugs decreased blood pressure and heart rate immediately after i.c.v. injection. These effects paralleled the beta-blocking potencies ((+)- greater than (+/-)-greater than (-)-nebivolol). Metoprolol induced a weaker hypotension than (+/-)-nebivolol, and a long-lasting reduction in stroke volume. As reported after i.v. administration, (+/-)-nebivolol and isomers by the i.c.v. route decreased peripheral vascular resistance following i.c.v. administration while metoprolol increased it. These effects are centrally mediated since cardiovascular responses to isoprenaline i.v. remained unchanged.

Prognostic factors in patients with stage I epithelial ovarian cancer

We analyzed factors predictive of relapse risk in patients with stage I invasive epithelial ovarian cancer: 252 patients from the Princess Margaret Hospital provided a data base for hypothesis generation, and data on 267 patients from the Norwegian Radium Hospital were used for hypothesis testing. The outcomes in most analyses in the two series were very similar, validating the following conclusions. Differentiation (grade) was the most powerful predictor of relapse, followed by dense adherence (which resulted in outcomes equivalent to those in stage II) and, finally, large-volume ascites. When the effects of these three factors were accounted for, then none of the following were prognostic: bilaterality (stage Ib), cyst rupture (stage Ic), capsular penetration (stage Ic), tumor size, histologic subtype, patient age, year of diagnosis, and postoperative therapy. These results allow simplification of stage I substaging, as only differentiation, dense adherence, and large-volume ascites (? peritoneal cytology) need be considered. The 5-year relapse-free rate was 98% in patients with grade 1 tumors in whom both dense adherence and large-volume ascites were absent. These patients are adequately treated by operation alone. Although the relapse risk was high enough in the remaining patients to warrant postoperative treatment, a significant benefit could be shown only for a small subset of patients, namely those with densely adherent tumors treated with abdominopelvic radiotherapy. In grades 2 and 3, none of the therapies used in either series was superior to pelvic radiotherapy or operation alone.

Colony-forming ability of human ovarian carcinomas in the Courtenay soft agar assay

One hundred and twenty-one ovarian carcinomas were cultivated in soft agar according to the Courtenay & Mills (C-M) soft agar method. 71% of the tumours formed colonies, and 54% formed more than 30 colonies. Tumour cells from malignant fluids grew more frequently than did solid tumours, whereas the plating efficiencies (PEs) were higher in the case of solid tumours. In general, the PEs were higher and more tumours formed colonies in the C-M method compared to the Hamburger-Salmon (H-S) method. The colony-forming ability did not show statistically significant correlation to histopathological type and grade, previous treatment and S-phase fraction, but was related to DNA ploidy. In poorly differentiated tumours a high colony-forming ability was associated with a poor prognosis, whereas the opposite was found in well and moderately differentiated tumours. Differential dose-response relationships were obtained after in vitro treatment with anticancer agents.

Influence of infusion time on unchanged cisplatin disposition in patients with ovarian cancer

The disposition of unchanged cisplatin in ten patients with ovarian cancer receiving 2-h infusions of 100 mg/m2 was compared with that of ten patients receiving 6-h infusions. A high-performance liquid chromatographic assay specific for the unchanged drug was used and all collected samples were rapidly processed. Patients were catheterized for urine collections. Cisplatin renal clearance was significantly lower after 6-hour infusions (52.8 +/- 16.2 ml/min per m2) than after 2-h infusions (87.1 +/- 38.2 ml/min per m2) (P = 0.026). Total clearance was also lower and less variable, although not significantly, in patients receiving the longer infusion. No differences in nonrenal clearance, volume of distribution, or half-life were observed between the two groups. There was only a poor relationship between cisplatin renal clearance and creatinine clearance after 2-h (r2 = 0.02; P = 0.66) and 6-h infusions (r2 = 0.18; P = 0.23). A single cisplatin plasma level obtained at the end of the infusion proved to be a good predictor of total cisplatin clearance after both 2-h (r2 = 0.70; P = 0.0096) and 6-h infusions (r2 = 0.97; P = 0.0001). This level was not significantly related to the relatively small changes in creatinine clearance that occurred after three courses of treatment.

Presynaptic beta-adrenoceptors in rat atria: evidence for the presence of stereoselective beta 1-adrenoceptors

1. Presynaptic beta-adrenoceptor activity was studied in rat isolated atria, previously loaded with [3H]-noradrenaline. The stimulation-induced release of 3H transmitter was measured in the presence of cocaine, and adrenaline was used as a facilitatory beta-adrenoceptor agonist. 2. Adrenaline (0.1 and 2 nM) increased, by about 50%, the evoked efflux of tritium. With phenoxybenzamine present, the same activity was shown with 10 nM adrenaline. 3. The beta 2-selective adrenoceptor blocking drugs: IPS 339 and ICI 118 551 caused a concentration-dependent decrease in the activity of adrenaline. Cardioselective beta-blocking drugs: acebutolol, beta-xolol, nebivolol and its isomers (R 67 138 and R 67 145) also reduced dose-dependently the agonistic action of adrenaline. The order of potency for nebivolol and its isomers was R 67 138 greater than nebivolol greater than R 67 145. The activity of pindolol was not concentration-dependent. The inhibitory effect of acebutolol was also observed in the presence of blockade of alpha-adrenoceptors. 4. The postsynaptic beta-adrenoceptor blocking activity of nebivolol and its isomers was studied in pithed rats. They reduced isoprenaline-induced tachycardia without altering hypotensive responses. The order of potency was: R 67 138 greater than nebivolol greater than R 67 145. 5. It is concluded that in rat isolated atria, presynaptic beta 2- and beta 1-adrenoceptors coexist and that facilitatory beta 1-adrenoceptors are stereospecific.

Cervical cancer in South Australia: trends in incidence, mortality and case survival

Approximately 90% of cervical cancers are considered preventable through regular screening and the treatment of precursor lesions, but fewer than 20% of South Australian women were found to have been screened in 1984. Data from the State Cancer Registry have shown an increase in cervical cancer incidence of approximately 80% in women under 50 years of age in the 9-year period to 1986, but a decrease of about 25% in older women. Mortality data have shown similar patterns by age, although the increase in younger women tended to extend to an older age. Case survival was unchanged between the diagnostic periods 1977-1981 and 1982-1987 and there was little change in the proportion of cases that were adenocarcinomas.

Misonidazole combined with radiotherapy in the treatment of carcinoma of the uterine cervix

Between April 1979 and January 1982, 331 patients were included in a study to establish whether misonidazole (MISO) had any effect as an adjuvant to radiotherapy in the treatment of squamous cell carcinoma of the uterine cervix (FIGO Stage IIb, III, and IVa). Patients were randomized to receive either MISO (12 g/m2 applied within 6 weeks) or placebo. This was given in conjunction with each institution's normal radiotherapy schedule and thus varied with regard to external and intracavitary irradiation. The analysis was performed based on patients' status at January 1986, with all patients observed for at least 4 years. One hundred and sixty-four patients received MISO and 167 placebo. Compliance to radiotherapy was good and MISO was well tolerated. The overall rates for MISO vs. placebo were as follows: local tumour control, 50 vs. 54%; disease-free survival, 47 vs. 46%, and crude survival, 39 vs. 45%. A similar lack of MISO effect was found in the individual stages. However, patients in all stages with hemoglobin concentrations below 7 mmol/l had a significantly lower local control probability (overall 24 vs. 47%), whereas the incidence of distant metastases was unaffected. We conclude that the addition of MISO did not influence the radiation response in advanced uterine carcinoma. The reasons for this ineffectiveness are yet to be clarified.