Immune Activation following Irbesartan Treatment in a Colorectal Cancer Patient: A Case Study

Colorectal cancers are one of the most prevalent tumour types worldwide and, despite the emergence of targeted and biologic therapies, have among the highest mortality rates. The Personalized OncoGenomics (POG) program at BC Cancer performs whole genome and transcriptome analysis (WGTA) to identify specific alterations in an individual's cancer that may be most effectively targeted. Informed using WGTA, a patient with advanced mismatch repair-deficient colorectal cancer was treated with the antihypertensive drug irbesartan and experienced a profound and durable response. We describe the subsequent relapse of this patient and potential mechanisms of response using WGTA and multiplex immunohistochemistry (m-IHC) profiling of biopsies before and after treatment from the same metastatic site of the L3 spine. We did not observe marked differences in the genomic landscape before and after treatment. Analyses revealed an increase in immune signalling and infiltrating immune cells, particularly CD8+ T cells, in the relapsed tumour. These results indicate that the observed anti-tumour response to irbesartan may have been due to an activated immune response. Determining whether there may be other cancer contexts in which irbesartan may be similarly valuable will require additional studies.

Comparison of methods for assessing synergic antibiotic interactions

Twenty-five combined microtitre chequerboard/time kill curves were performed on ten isolates from patients with relapsing infection to assess the potential for combination therapy. The isolates were Burkholderia cepacia, Staphylococcus aureus and Klebsiella pneumoniae. No antagonism (FIC index or FBC index >4) was observed with any combination. Synergy by time kill curve (present in 21 combinations) was more often seen at 24 h than 2 or 5 h (P<0.001). On comparing the mean of the FIC and FBC indices, there were significant differences in only four chequerboards (P<0.05). The same checkerboard was repeated on 3 separate days to test reproducibility. There were no significant differences (P>0.05). All combinations showing synergism by FBC index were synergic by FIC index. Synergy by FIC index predicted synergy by FBC index in 67%. All combinations showing synergism by FIC index were synergic by time kill at 24 h but there was poor correlation between synergy at 2 or 5 h and synergy by FIC index or FBC index. In conclusion combining time kill and chequerboard tests gives reproducible results and good correlation between FIC and FBC indices. FIC indices showing synergy were also predictive of synergy in time kill studies. For bactericidal combinations unlikely to be antagonistic, calculation of FIC index may be a good indicator of synergic bactericidal activity.

Comparison of the E test with broth microdilution for antifungal susceptibility testing of yeasts

The susceptibilities of 26 recent invasive clinical isolates to amphotericin B (AMP), 5-flucytosine (5FC), fluconazole (FLU) and itraconazole (ITR) were determined by a broth microdilution modification of the NCCLS M27P method and also by E test. Using breakpoint criteria each result was classified as either sensitive (S), intermediate (I) or resistant (R). Taking the optical density (OD)80 as the standard, the results were further classified into major (M) or minor (m) errors. E test: AMP = 0M 0m, 5FC = 0M 5m, FLU = 1M 12m, ITR = 1M 5m errors. Minimal inhibitory concentrations (MIC): AMP = 0M 2m, 5FC = 0M 0m, FLU = 3M 4m, ITR = 1M 7m errors. The E test was quick and relatively simple to perform. Results using the E test compared favourably with those of the OD80 and it should be suitable for the routine susceptibility testing of yeasts to antifungal agents.

Arthroscopic diagnosis of intra-articular soft tissue injuries associated with distal radial fractures

Arthroscopy was used to assess the soft tissue injuries associated with distal radial fractures in 118 acute intra- and extra-articular fractures. The triangular fibrocartilage complex (TFCC) was torn in 46 of 118 patients--in 35% of intra-articular fractures and in 53% of extra-articular fractures. No correlation between ulnar styloid fractures and TFCC injuries could be found. Scapholunate (SL) ligament injuries with instability were present in 21.5% of intra-articular fractures and in 6.7% of extra-articular fractures. Lunotriquetral (LT) ligament injuries with instability were present in 6.7% of intra-articular fractures. and in 13.3% of extra-articular fractures. Combined SL and LT injuries were present in 5.6% of intra-articular fracture. Preoperative radiographs correlated with TFCC injury. Patients with TFCC tears had greater shortening and dorsal angulation on the preoperative radiographs. Preoperative radiographs had no predictive value for interosseous ligament injury. Ligamentous injuries are commonly associated with both intra-articular and extra-articular distal radial fractures.

In-vitro pharmacodynamic studies of piperacillin/tazobactam with gentamicin and ciprofloxacin

Six isolates each of Enterococcus faecium, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Stenotrophomonas maltophilia, Pseudomonas aeruginosa, Citrobacter spp., Serratia spp., Acinetobacter spp. and Enterobacter spp. (total 60 strains) were studied against the combination of piperacillin/tazobactam plus gentamicin or ciprofloxacin at physiological concentrations by the microtitre chequerboard method incorporating simultaneous time-kill curves. Tazobactam was fixed at 4 mg/L. Gentamicin plus piperacillin/tazobactam was a synergic combination against 28 strains at 2 h, 51 at 5 h and 54 at 24 h as assessed by time-kill curves and synergic or additive (FBC index < or = 1) against all 60 strains at 24 h by chequerboards. The corresponding figures for ciprofloxacin plus piperacillin/tazobactam were seven, 26, 52 and 58 respectively. Antagonism (FBC index > or = 4) was demonstrated for one strain to each combination at 24 h. There were no significant differences between FIC indices and FBC indices for each antibiotic combination. Gentamicin plus piperacillin/tazobactam gave > or = 3 log kill for 47 strains by 2 h, 56 by 5 h and 59 by 24 h. Ciprofloxacin plus piperacillin/tazobactam gave > or = 3 log kill for 22 strains by 2 h, 36 by 5 h and 56 by 24 h. In conclusion both antibiotic combinations at physiological concentrations were synergic or additive at 24 h for the majority of strains tested although notably gentamicin plus piperacillin/tazobactam gave faster kill. Antagonism was rarely seen. Both combinations are likely to prove beneficial for treatment of serious infections.

Adherence to the Grampian joint drug formulary in general practice

A joint drug formulary covering both hospital and general practice prescribing has been in existence in Grampian since 1990. The aims of this study were to measure adherence to this formulary in general practice and to identify who had initiated non-formulary drugs. The drug therapy of elderly patients on presentation to hospital was compared to the formulary. Of the 449 drugs prescribed 377 (84%) were recommended in the formulary. The main areas of non-formulary prescribing were antidepressants, hypnotics, nitrates and diuretics, with some non-formulary drugs being initiated by hospital prescribers. The method described was found to be extremely simple and had the advantage that it reflected actual prescribing at the time of the study.

Evaluation of Phosphoramide Derivatives of Carboxylic Acid Esters for the Alkylation of Tricarbonyliron Complexes With Weak Regiodirecting Groups

Enolates derived from phosphoramide derivatives of carboxylic acid esters were found to act as regiocontrolled nucleophiles for the alkylation of tricarbonyl (η5-cyclohexadienyl)iron(1+) salts, even in cases where weak (Me) regiodirecting groups were present as unsymmetrically placed substituents. The nucleophiles, however, lacked the correct degree of basicity needed for high-yielding reactions.

Interaction of imipenem with erythromycin and tetracycline assessed by microdilution checkerboard techniques

Microdilution methodology was used to study the interaction of imipenem with erythromycin and tetracycline, a combination therapy that might be used for the treatment of serious pelvic inflammatory disease. The combination of imipenem and erythromycin showed no antagonism for Escherichia coli and Haemophilus influenzae but was antagonistic for Staphylococcus aureus, Enterococcus faecalis, and group B streptococci; the combination of imipenem and tetracycline was antagonistic for all strains except H. influenzae. Correlation between the results of kill curves and the measurement of fractional bactericidal concentration (FBC) indices was good, although FBC indices showed less antagonism than kill curves. Fractional inhibitory concentration indices showed poor correlation, rarely showing antagonism, and indeed showed synergy in three cases. If erythromycin or tetracycline is considered necessary in addition to imipenem in the treatment of pelvic inflammatory disease, it is probably more effective when given after the course of imipenem has been completed.

Ionic binding, adaptive resistance and post-antibiotic effect of netilmicin and ciprofloxacin

Ionic binding, post-antibiotic effect (PAE) and adaptive resistance to netilmicin and ciprofloxacin were investigated in 11 distinct clinical isolates. Both netilmicin and ciprofloxacin showed concentration dependent kill and PAE when bacteria were exposed to these antibiotics at 37 degrees C. The effects of netilmicin were maintained at 4 degrees C, when there is no energy dependent cell uptake of antibiotic, but were partially inhibited by exposure to NaCl and EDTA although not by Ca++. This supports the concept that ionic binding to the bacterial cell wall is important in the initial uptake of netilmicin. Ciprofloxacin showed no such effects at 4 degrees C. Adaptive resistance (reduced bacterial kill on second exposure) occurred with both netilmicin and ciprofloxacin but was seen more frequently with netilmicin. It persisted longer than classical PAE but, even after continuous exposure, was not enough to suggest a loss of kill with a twice daily dosing regimen of netilmicin or ciprofloxacin.

Regulation of prostaglandin synthesis in the human amnion

An increase in prostaglandin synthesis by intrauterine tissues may be responsible for labour initiation and/or maintenance in humans. In all studies to date, the amnion is the intrauterine tissue whose prostaglandin output consistently increases with the onset of labour. This may be due, in part, to acute activation of the phospholipases A2 and C and to an increase in the specific activity of prostaglandin H synthase (PGHS). A number of factors exist in amniotic fluid, the fetal membranes, the decidua and the placenta that can increase PGHS specific activity. Some of these factors may increase PGHS enzyme activity by gene expression and protein synthesis. Preliminary evidence is presented that suggests the hypothesis that PGHS specific activity increases before the onset of labour rather than as a consequence of labour initiation, and that idiopathic preterm labour may frequently be associated with increased PGHS activity. Hence, activation of PGHS gene expression and/or protein synthesis may be causal for term and preterm labour.

Use of the Malthus Microbial Growth Analyser to study the post antibiotic effect of antibiotics

The post antibiotic effect (PAE) of ceftazidime, ciprofloxacin, mecillinam and imipenem alone and in combination against Gram-negative bacteria was assessed by a new technique using a Malthus Microbial Growth Analyser. Ciprofloxacin gave the most prolonged and consistent PAE (1.3-2.9 h) and imipenem also gave a significant PAE against some bacterial strains (up to 1.3 h). The PAE of both antibiotics was dependent on concentration. The PAE of combinations of ciprofloxacin and imipenem often showed less PAE than was present with either agent alone. Ceftazidime gave no significant PAE (-1.5-0.4 h), though mecillinam consistently gave a short PAE (approximately 0.5 h) against Escherichia coli. The new method allows for the rapid and labour saving evaluation of PAE. We believe that further studies on PAE of antibiotic combinations are desirable.

Prevalence rates and demographic characteristics associated with depression in pregnancy and the postpartum

Examined the prevalence of depression in a heterogeneous sample of 360 pregnant women. Subjects were assessed with respect to both depressive symptomatology and diagnostic status during pregnancy and after delivery. At both assessments, approximately 25% of the sample reported elevated levels of depressive symptomatology. In contrast, 10% of the women met diagnostic criteria for depression during pregnancy, and 6.8% were depressed postpartum. However, only half of the cases of postpartum depression were new onset (3.4%); the remaining women receiving a diagnosis in the postpartum had also been depressed during pregnancy. Finally, depression during pregnancy was related to different sociodemographic variables than was postpartum depression, suggesting that depression at these two times may be associated with different psychological or etiological factors.

Prevalence rates and demographic characteristics associated with depression in pregnancy and the postpartum

Examined the prevalence of depression in a heterogeneous sample of 360 pregnant women. Subjects were assessed with respect to both depressive symptomatology and diagnostic status during pregnancy and after delivery. At both assessments, approximately 25% of the sample reported elevated levels of depressive symptomatology. In contrast, 10% of the women met diagnostic criteria for depression during pregnancy, and 6.8% were depressed postpartum. However, only half of the cases of postpartum depression were new onset (3.4%); the remaining women receiving a diagnosis in the postpartum had also been depressed during pregnancy. Finally, depression during pregnancy was related to different sociodemographic variables than was postpartum depression, suggesting that depression at these two times may be associated with different psychological or etiological factors.

A Simulation Model of Heterodera schachtii Infecting Beta vulgaris

A simulation model of a single sugarbeet, Beta vulgaris L., plant infected by the sugarbeet cyst nematode, Heterodera schachtii Schmidt, was developed using published information. The model is an interactive computer simulation programmed in FORTRAN. Given initial population densities of the nematode at planting, the model simulates nematode population dynamics and the growth of plant tap and fibrous roots. The driving variable for nematode development and plant growth is temperature.

Conjugated estrogens and breast cancer risk in women

The relationship between conjugated estrogen(s) (CE) and breast cancer was investigated by the examination of the records of 345 women with newly diagnosed breast cancer and 611 healthy controls belonging to a prepaid health plan. Use of CE was associated with a 40% elevation in risk [relative risk (RR) = 1.4; 95% confidence interval-1.0-2.0]. The RR was 1.3 for menopausal women with intact ovaries and 1.5 for those with ovaries removed. There was statistically significant evidence of a dose-response relationship with the three measures of dose evaluated. RR's rose to about twofold for women with 10 or more CE prescriptions noted in their charts, for those with 5 years or more between their first and last prescription, and for those with a usual daily dose of 1.25 mg or more. The RR associated with having ever used CE and with long-term use was highest among those women with a family history of breast cancer. These data support the hypothesis that long-term use of CE is associated with increased breast cancer risk.