A mixed methods pilot and feasibility open trial of internet-delivered cognitive behaviour therapy (iCanADAPT Advanced) for people with advanced cancer with depression and/or anxiety

PURPOSE

Evaluate the feasibility, acceptability and potential efficacy of a form of online therapy for clinical depression and/or anxiety in people living with advanced cancer.

METHODS

A single-arm open trial of a six-lesson clinician-supervised, internet-delivered cognitive behavioural therapy (iCBT) transdiagnostic intervention (iCanADAPT Advanced) was undertaken. Qualitative (semi-structured telephone interview conducted at 3-months) and quantitative data (questionnaires collected at pre-, post-, and 3-month follow-up) were analysed.

RESULTS

27 participants partook (26 women, 56% breast cancer, mean age 56yo; average number of mental health diagnoses 1.8, with majority (81%) meeting criteria for generalised anxiety disorder). Feasibility - Unanticipated numbers (48%) of participants had physical health deterioration (cancer progression or death). iCBT had high adherence overall (completion rates: 37% did 6 lessons; 70% did 4 lessons) but adherence was higher for those whose cancer remained stable (completion rates: 43% did 6 lessons; 85% did 4 lessons). Acceptability - the intervention was acceptable to the majority of participants, with high treatment satisfaction. Advisory data was achieved regarding future versions. Potential efficacy - regardless of physical health status, participants who completed the iCBT showed a significant decrease over time in anxiety and depression symptoms.

CONCLUSIONS

Online therapies may be useful in assisting those living with advanced cancer dealing with clinical depression and anxiety disorders. The specific modality of clinician supervised iCBT has significant potential to be a suitable modality of online therapy.

The immuno-oncological implications of insulin

Emerging evidence has implicated insulin in regulating the phenotypes of various immune cells through canonical downstream signalling effectors of insulin, namely, the PI3K/Akt/mTOR pathway. Notably, these signalling components also exhibit crosstalk with other immune signalling pathways, such as the JAK/STAT pathway (activated by cytokines and growth factors), and, importantly, are also negatively regulated by the immune checkpoint blockers (ICBs), PD-1 and CTLA-4. Here, we point out recent findings, suggesting that insulin may promote a pro-inflammatory phenotype with potential implications on ICB therapy. As an example, the contemporary paradigm holds that, while T cell receptor recognition of distinct MHC-expressed epitopes ensures specificity, co-activation of CD28 along with signal inputs form various cytokines and insulin operates to 'fine-tune' the immune response via PI3K and other downstream signalling molecules. These considerations highlight the urgent need for focused investigations into the role of insulin in regulating immune cell function in the context of ICB therapies.

Age-specific characteristics of neutrophilic dermatoses and neutrophilic diseases in children

BACKGROUND

Our suggested 'modern' concepts of 'neutrophilic dermatoses' (ND) and 'neutrophilic disease' were based on observations in adult patients and have not been studied in paediatric patients. Only a minority of ND occurs in children, and little is known about age-specific characteristics.

OBJECTIVES

To describe age-specific characteristics of ND in children and to study whether our suggested 'modern' classification of ND may be applied to children.

METHODS

We conducted a retrospective multicentre study in a French cohort of 27 paediatric patients diagnosed with pyoderma gangrenosum (PG) or Sweet's syndrome (SS).

RESULTS

Demographics and distribution of typical/atypical forms were similar in patients diagnosed with PG and SS. Atypical ND were more frequent in infants (90%), when compared to young children (60%) and adolescents (33%). Neutrophilic disease was observed in 17/27 patients and was most frequent in infants. Neutrophilic disease of the upper respiratory tract, as well as cardiac neutrophilic disease, was only observed in infants, whereas other locations were similarly found in infants, young children and adolescents. In infants and young children, ND were associated with a large spectrum of general diseases, whereas in adolescents associations were limited to inflammatory bowel disease and Behçet's disease.

CONCLUSIONS

Our study describes the concept of ND in paediatric patients and shows that they have some characteristics different from ND occurring in adults. ND occurring in infants can be associated with a large spectrum of general diseases. Occurrence of neutrophilic disease is frequent in children. Thus, ND occurring in young paediatric patients should incite clinicians to schedule complementary explorations in order to search for involvement of other organs and to rule out monogenetic autoinflammatory syndromes.

Ecoconception des caves : réduction de la consommation d'énergie et intégration paysagère du traitement des effuents de cave avec le dispositif de lit planté de roseaux sur support de zéolithe Zeofito®

Le traitement aérobie des effuents vinicoles est majoritairement utilisé dans les caves. Au-delà des impératifs de performance d'épuration, avec les orientations de développement durable, le traitement doit intégrer plusieurs orientations : faible consommation d'énergie, limitation des boues, valorisation paysagère et de la biodiversité, limitation des nuisances olfactives et sonores, et éventuellement la réutilisation des effuents traités pour l'irrigation. Les dispositifs classiques de phyto-épuration sur lit de sable, qui permettent de traiter des effuents avec une DCO généralement inférieure à 2 g/l, imposent le plus souvent un bassin de stockage aéré conséquent, consommateur d'énergie, source éventuelle de nuisance olfactive, visuelle et sonore. Le procédé Zeofito®, qui équipe maintenant une centaine de caves dans différentes régions italiennes, accentue grâce au support de zéolithe, les mécanismes d'adsorption et de biodégradation. Ainsi, il est possible de réaliser un traitement direct ou éventuellement avec un petit bassin de stockage d'égalisation/aération, correspondant à quelques jours de rejet. La réutilisation de l'eau pour le dispositif de refroidissement de la cave ou l'irrigation des vignes est facilitée comparativement aux dispositifs classiques. Parallèlement au principe et aux performances, l'objectif de la communication est de présenter des installations représentatives de la diversité des caves.

An in vitro and in vivo study on the properties of hollow polycaprolactone cell-delivery particles

The field of dermal fillers is evolving rapidly and numerous products are currently on the market. Biodegradable polymers such as polycaprolactone (PCL) have been found to be compatible with several body tissues, and this makes them an ideal material for dermal filling purposes. Hollow PCL spheres were developed by the Council for Scientific and Industrial Research (CSIR) to serve both as an anchor point and a "tissue harbour" for cells. Particles were tested for cytotoxicity and cell adherence using mouse embryo fibroblasts (MEF). MEFs adhered to the particles and no significant toxic effects were observed based on morphology, cell growth, cell viability and cell cycle analysis, suggesting that the particles are suitable candidates for cell delivery systems in an in vivo setting. The objective of providing a "tissue harbour" was however not realized, as cells did not preferentially migrate into the ported particles. In vivo studies were conducted in BALB/c mice into whom particles were introduced at the level of the hypodermis. Mice injected with PCL particles (ported and non-ported; with or without MEFs) showed evidence of local inflammation and increased adipogenesis at the site of injection, as well as a systemic inflammatory response. These effects were also observed in mice that received apparently inert (polystyrene) particles. Ported PCL particles can therefore act as a cell delivery system and through their ability to induce adipogenesis, may also serve as a dermal bulking agent.

Solution-mediated crystallization of amorphous azithromycin

Water and water vapor are the bane of amorphous drug stability, both in storage and after administration. As is to be expected, crystallization of amorphous azithromycin did occur when exposed to water as dissolution medium. However, experimental results showed that, although solution-mediated phase transformation had occurred, it was not a rapid process for this drug. It is considered to be an advantageous characteristic of amorphous azithromycin and likely due to the high molecular mass (748.984 g/mol) and complex structure necessitating more energy for transformations to occur. A high apparent solubility is maintained for a considerable period of time, potentially rendering a higher percentage of this BCS Class II drug available for absorption when administered orally.

Quantification of the fungal fraction released from various preloaded fibrous filters during a simulated ventilation restart

This study aimed to demonstrate that particles, especially those associated with fungi, could be released from fibrous filters used in the air-handling unit (AHU) of heating, ventilation and air-conditioning (HVAC) systems during ventilation restarts. Quantification of the water retention capacity and SEM pictures of the filters was used to show the potential for fungal proliferation in unused or preloaded filters. Five fibrous filters with various particle collection efficiencies were studied: classes G4, M5, M6, F7, and combined F7 according to European standard EN779:2012. Filters were clogged with micronized rice particles containing the fungus Penicillium chrysogenum and then incubated for three weeks at 25°C and 90% relative humidity. The results indicated that the five clogged tested filters had various fungal growth capacities depending on their water retention capacity. Preloaded filters were subjected to a simulated ventilation restart in a controlled filtration device to quantify that the fraction of particles released was around 1% for the G4, 0.1% for the M5 and the M6, and 0.001% for the F7 and the combined F7 filter. The results indicate that the likelihood of fungal particle release by low efficiency filters is significantly higher than by high efficiency filters.

Piperine alleviates osteoclast formation through the p38/c-Fos/NFATc1 signaling axis

Increased bone fracture is one of the health risk factors in patients with bone loss related disorders such as osteoporosis and breast cancer metastasis to bone. Over activity of osteoclasts leads to uncoupling of bone remodeling favoring bone loss over bone formation. Receptor activator of nuclear factor-κβ ligand (RANKL) triggers the differentiation pathway leading to multinucleated osteoclast formation. Modulation of RANKL or its downstream signaling pathways involved in osteoclast formation is of significant interest in the development of anti-resorptive agents. In this study, the effects of piperine, an alkaloid present in Piper nigrum L. on osteoclast formation was investigated. Piperine inhibited tartrate-resistant acid phosphatase-positive multinucleated osteoclast formation in murine RAW264.7 macrophages and human CD14+ monocytes induced by RANKL and breast cancer cells. Piperine attenuated the p38-mitogen activated protein kinase pathway activation, while the extracellular-signal-regulated kinase, c-Jun N-terminal kinase, or NF-κβ pathways downstream of RANKL remained unaffected. Concomitantly, expression of c-Fos and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), the key transcription factors involved in osteoclastogenesis were remarkably inhibited by piperine. Furthermore, piperine disrupted the actin ring structure and bone resorption, a characteristic hallmark of osteoclasts. Collectively, these results suggested that piperine inhibited osteoclast differentiation by suppressing the p38/NFATc1/c-Fos signaling axis..

Behavior and Fate of Halloysite Nanotubes (HNTs) When Incinerating PA6/HNTs Nanocomposite

Nanoclay-based nanocomposites have been widely studied and produced since the late 1990s, and frequently end up in waste disposal plants. This work investigates the behavior of PA6/HNTs nanocomposites (nylon-6 incorporating halloysite nanotubes) during incineration. Incineration tests were performed at lab-scale using a specific tubular furnace modified in order to control the key incineration parameters within both the combustion and postcombustion zones. The combustion residues and combustion aerosol (particulate matter and gas phase) collected downstream of the incinerator furnace were characterized using various aerosol analysis techniques. Time tracking of the gas and particle-number concentrations revealed two-step char formation during combustion. HNTs transformed into other mineral structures which were found in both the aerosol and the residues. During combustion of the polymer, it appears that HNTs contribute to the formation of a cohesive char layer that protects the residual material.

Novel in silico-designed estradiol analogues are cytotoxic to a multidrug-resistant cell line at nanomolar concentrations

PURPOSE

2-Methoxyestradiol (2ME) is a promising anti-cancer agent that disrupts the integrity and dynamics of the spindle network. In order to overcome the pharmacokinetic constraints of this compound, a panel of sulphamoylated estradiol analogues were in silico-designed by our laboratory. In this study, we analysed the potential of each analogue to induce cell death on a panel of cancer cell lines. Moreover, the mechanism of action of the most effective compounds was determined.

METHODS

Cytotoxicity screening of the compounds and intermediates was performed on five different cancer cell lines to determine IG50 values. An in vitro tubulin polymerization assay was done to determine the effect of the drugs on tubulin polymerization while their intracellular effects on the microtubule network were assessed by immunofluorescence microscopy.

RESULTS

IG50 calculations showed that the sulphamoylated analogues induce cytotoxicity at nanomolar concentrations in all cell lines, including the P-glycoprotein pump overexpressing multidrug-resistant uterine sarcoma cell line. The non-sulphamoylated compounds were only cytotoxic at micromolar ranges, if at all. The sulphamoylated compounds inhibited pure tubulin polymerization in a dose-dependent manner and induced microtubule destruction in cells after 24-h exposure.

CONCLUSION

Results revealed that the novel sulphamoylated 2ME derivatives have potential as anti-cancer drugs, possibly even against chemoresistant cancer cells. These compounds disrupt the intracellular microtubule integrity which leads to mitotic block of the cells.

New method using quantitative PCR to follow the tick blood meal and to assess the anti-feeding effect of topical acaricide against Rhipicephalus sanguineus on dogs

A 28-day study was conducted to assess the dynamic of blood feeding by Rhipicephalus sanguineus ticks on dogs treated or not with a novel topical combination of fipronil, amitraz and (S)-methoprene. Dogs were infested weekly through exposure to ticks in crates for 4h. Ticks were then counted in the crates at 2h and 4h post dog exposure. Ticks were also counted and removed from the dogs at 2h, 4h, 6h, 12h and 24h post tick exposure. The inhibition of blood feeding was assessed by both tick quantification and designing and performing a quantitative PCR (qPCR) to detect the canine hydroxymethylbilane synthase (HMBS) gene in ticks. The percentage of repellency sensu lato based on the ticks collected in crates at 2h varied from 4.7% at day 28 to 48.3% at day 7. The immediate mortality rate of the ticks expelled at 2h varied from 1.5% at day 21 to 31.7% at day 7. The efficacy calculation showed that the acaricidal combination started to kill ticks in as little as 2h. The average efficacy reached 90.0% at 12h post crate challenges and 100% at 24h post exposure in crates. The inclusion of an internal amplification control was used to ensure that no significant template-derived PCR inhibition (≤ 6.2%) affected the overall results. The reduction of blood feeding was significant at 4h (>80.0%) and >99.0% at 24h post tick exposure in the crate. The high repellency rate and the lethal efficacy of CERTIFECT(®) resulted in significantly fewer live attached ticks, consequently reducing blood intake and fluid exchanges.

Novel estradiol analogue induces apoptosis and autophagy in esophageal carcinoma cells

Cancer is the second leading cause of death in South Africa. The critical role that microtubules play in cell division makes them an ideal target for the development of chemotherapeutic drugs that prevent the hyperproliferation of cancer cells. The new in silico-designed estradiol analogue 2-ethyl-3-O-sulfamoylestra-1,3,5(10)16-tetraene (ESE-16) was investigated in terms of its in vitro antiproliferative effects on the esophageal carcinoma SNO cell line at a concentration of 0.18 μM and an exposure time of 24 h. Polarization-optical differential interference contrast and triple fluorescent staining (propidium iodide, Hoechst 33342 and acridine orange) revealed a decrease in cell density, metaphase arrest, and the occurrence of apoptotic bodies in the ESE-16-treated cells when compared to relevant controls. Treated cells also showed an increase in the presence of acidic vacuoles and lysosomes, suggesting the occurrence of autophagic processes. Cell death via autophagy was confirmed using the Cyto-ID autophagy detection kit and the aggresome detection assay. Results showed an increase in autophagic vacuole and aggresome formation in ESE-16 treated cells, confirming the induction of cell death via autophagy. Cell cycle progression demonstrated an increase in the sub-G1 fraction (indicative of the presence of apoptosis). In addition, a reduction in mitochondrial membrane potential was also observed, which suggests the involvement of apoptotic cell death induced by ESE-16 via the intrinsic apoptotic pathway. In this study, it was demonstrated that ESE-16 induces cell death via both autophagy and apoptosis in esophageal carcinoma cells. This study paves the way for future investigation into the role of ESE-16 in ex vivo and in vivo studies as a possible anticancer agent.

Induction of the intrinsic apoptotic pathway via a new antimitotic agent in an esophageal carcinoma cell line

Background

2-Ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16) is a unique, in silico-designed compound with possible anticancer properties, which were identified in our laboratory. This compound is capable of interfering with microtubule dynamics and is believed to have potential carbonic anhydrase IX inhibiting activity.

In this study, it was investigated whether ESE-16 is capable of inducing apoptosis in vitro in the esophageal carcinoma SNO cell line via the intrinsic pathway at a concentration of 0.2 μM with an exposure time of 24 hours.

Results

Qualitative results were obtained via light microscopy, transmission electron microscopy and confocal microscopy. Results showed hallmarks of apoptosis in the ESE-16-treated cells. In addition, data revealed an increase in the number of ESE-16-treated cells blocked in metaphase. Cell death via apoptosis in the ESE-16-treated cells was confirmed by studying the internal ultrastructure of the cells via transmission electron microscopy, while confocal microscopy revealed abnormal spindle formation and condensed chromatin in ESE-16-treated cells, thus confirming metaphase block.

Quantitative results were obtained via flow cytometry and spectrophotometry. Cell death via apoptosis in ESE-16-treated cells was quantitatively confirmed by the Annexin V-FITC apoptosis detection assay. Flow cytometry and spectrophotometry revealed dissipation of mitochondrial membrane potential and an increase in superoxide levels in the ESE-16-treated cells when compared to the relevant controls. Both initiator caspase 9 and effector caspase 3 activities were increased, which demonstrates that ESE-16 causes cell death in a caspase-dependent manner.

Conclusions

This was the first in vitro study conducted to investigate the action mechanism of ESE-16 on an esophageal carcinoma cell line. The results provided valuable information on the action mechanism of this potential anticancer agent. It can be concluded that the novel in silico-designed compound exerts an anti-proliferative effect on the esophageal carcinoma SNO cell line by disrupting microtubule function resulting in metaphase block. This culminates in apoptotic cell death via the intrinsic apoptotic pathway. This research provided cellular targets warranting in vivo assessment of ESE-16’s potential as an anticancer agent.

Diffusion-weighted magnetic resonance imaging for detecting and assessing ileal inflammation in Crohn's disease

BACKGROUND

Whether diffusion-weighted imaging (DWI)-MRI is of value in detecting and assessing inflammation of ileal Crohn's disease (CD) remains poorly investigated.

AIM

To compare DWI-MR enterography (MRE) with conventional MRE in estimating inflammation in small bowel CD, to determine an apparent diffusion coefficient (ADC) threshold to differentiate active from non-active lesions and to assess inter-observer agreement.

METHODS

Thirty-one CD patients from the Clermont-Ferrand IBD unit with ileal involvement were consecutively and prospectively included between April and June 2011. All patients underwent DWI-MRI to detect the digestive segment with the most severe lesions, which was then used to calculate the ADC. Qualitative and quantitative results were compared with conventional MRE including MaRIA (Magnetic Resonance Index of Activity) score calculation and independent activity predictors (wall thickening, oedema, ulcers). Each examination was interpreted independently by two radiologists blinded for clinical assessment.

RESULTS

Seventeen patients (54.8%) had active CD as defined by the MaRIA score ≥7. DWI hyperintensity was highly correlated with disease activity evaluated using conventional MRE (P = 0.001). Qualitative analysis of DW sequences determined sensitivity, specificity, positive predictive value and negative predictive value as 100%, 92.9%, 94.4% and 100% respectively. Quantitative analysis using a cut-off of 1.6 × 10(-3) mm(2)/s for ADC yielded sensitivity and specificity values of, respectively, 82.4% and 100%. Inter-observer agreement was high with regard to DWI hyperintensity (κ = 0.69, accuracy rate = 85.7%) and ADC (correlation = 0.74, P < 0.001, and concordance = 0.71, P < 0.001).

CONCLUSION

DWI-MR enterography is a well-tolerated, non-time-consuming and accurate tool for detecting and assessing inflammation in small bowel Crohn's disease.

Evolution of microbial aerosol behaviour in heating, ventilating and air-conditioning systems--quantification of Staphylococcus epidermidis and Penicillium oxalicum viability

The aim of this study was to develop an experimental set-up and a methodology to uniformly contaminate several filter samples with high concentrations of cultivable bacteria and fungi. An experimental set-up allows contaminating simultaneously up to four filters for range of velocities representative of heating, ventilating and air-conditioning systems. The test aerosol was composed of a microbial consortium of one bacterium (Staphylococcus epidermidis) and one fungus (Penicillium oxalicum) and aerosol generation was performed in wet conditions. Firstly, the experimental set-up was validated in regards to homogeneity of the air flows. The bioaerosol was also characterized in terms of number and particle size distribution using two particle counters: optical particle counter Grimm 1.109 (optical diameters) and TSI APS 3321 (aerodynamic diameters). Moreover, stabilities of the number of particles generated were measured. Finally, concentrations of cultivable microorganisms were measured with BioSamplers (SKC) downstream of the four filters.

Evolution of microbial aerosol behaviour in heating, ventilating and air-conditioning systems--quantification of Staphylococcus epidermidis and Penicillium oxalicum viability

The aim of this study was to develop an experimental set-up and a methodology to uniformly contaminate several filter samples with high concentrations of cultivable bacteria and fungi. An experimental set-up allows contaminating simultaneously up to four filters for range of velocities representative of heating, ventilating and air-conditioning systems. The test aerosol was composed of a microbial consortium of one bacterium (Staphylococcus epidermidis) and one fungus (Penicillium oxalicum) and aerosol generation was performed in wet conditions. Firstly, the experimental set-up was validated in regards to homogeneity of the air flows. The bioaerosol was also characterized in terms of the number and particle size distribution using two particle counters: optical particle counter Grimm 1.109 (optical diameters) and TSI APS 3321 (aerodynamic diameters). Moreover, stabilities of the number of particles generated were measured. Finally, concentrations of cultivable microorganisms were measured with BioSamplers SKC downstream of the four filters.

Differential signaling involved in Sutherlandia frutescens-induced cell death in MCF-7 and MCF-12A cells

ETHNOPHARMACOLOGICAL RELEVANCE

The scientific study of natural products traditionally used in anticancer preparations has yielded several therapeutically relevant compounds. One of these traditional preparations with potentially beneficial properties is aqueous extracts of Sutherlandia frutescens, a shrub indigenous to the Western Cape region of South Africa. The aims of this study were to evaluate in vitro efficacy of these preparations on the MCF-7 breast adenocarcinoma and MCF-12A non-tumorigenic cell lines in terms of cell proliferation, cell morphology and possible induction of cell death.

MATERIALS AND METHODS

Crystal violet staining was used to evaluate cell proliferation, light-and fluorescence microscopy were used to investigate both intracellular and extracellular morphological features of apoptosis and autophagy (e.g. membrane blebbing, condensed chromatin and intracellular lysosomes), while flow cytometry quantified cell cycle changes and induction of apoptosis through analysis of the flip-flop translocation of phosphatidylserine.

RESULTS

Crystal violet staining showed a time- and dose specific response to aqueous Sutherlandia frutescens extracts, revealing exposure to 1mg/ml aqueous extract for 48h to be ideal for comparing the differential effects of Sutherlandia frutescens in the MCF-7 and MCF-12A cell lines. Microscopy showed distinct morphological changes with hallmarks of apoptosis being observed in both cell lines. Flow cytometry revealed a decrease in actively cycling cells in both cell lines, and a 4.36% increase in phosphatidylserine translocation in the MCF-7 cell line, indicative of apoptosis induction, while fluorescence microscopy showed evidence of the induction of autophagy.

CONCLUSIONS

Analyses revealed the carcinogenic MCF-7 cell line to be more susceptible to the cytostatic and cytotoxic effects of aqueous extracts of Sutherlandia frutescens when compared to the non-tumorigenic MCF-12A cell line, thus warranting further research into the exact cellular mechanisms involved and the possible synergistic activities of Sutherlandia frutescens ingredients.

Impact of the unfolded protein response on the pathogenicity of the necrotrophic fungus Alternaria brassicicola

The unfolded protein response (UPR) is an important stress signalling pathway involved in the cellular development and environmental adaptation of fungi. We investigated the importance of the UPR pathway in the pathogenicity of the plant necrotrophic fungus Alternaria brassicicola, which causes black spot disease on a wide range of Brassicaceae. We identified the AbHacA gene encoding the major UPR transcription regulator in A. brassicicola. Deletion of AbHacA prevented induction of the UPR in response to endoplasmic reticulum stress. Loss of UPR in mutants resulted in a complete loss of virulence and was also associated with a cell wall defect and a reduced capacity for secretion. In addition, our results showed that the UPR was triggered by treatment of mycelia with camalexin, i.e. the major Arabidopsis thaliana phytoalexin, and that strains lacking functional AbHacA exhibited increased in vitro susceptibility to antimicrobial plant metabolites. We hypothesize that the UPR plays a major role in fungal virulence by altering cell protection against host metabolites and by reducing the ability of the fungus to assimilate nutrients required for growth in the host environment. This study suggests that targeting the UPR pathway would be an effective plant disease control strategy.

Docking, synthesis, and in vitro evaluation of antimitotic estrone analogs

In the present study, Autodock 4.0 was employed to discover potential carbonic anhydrase IX inhibitors that are able to interfere with microtubule dynamics by binding to the Colchicine binding site of tubulin. Modifications at position 2' of estrone were made to include moieties that are known to improve the antimitotic activity of estradiol analogs. 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10),15-tetraen-3-ol-17-one estronem (C9) and 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (C12) were synthesized and tested in vitro. Growth studies were conducted utilizing spectrophotometrical analysis with crystal violet as DNA stain. Compounds C9 and C12 were cytotoxic in MCF-7 and MDA-MB-231 tumorigenic and metastatic breast cancer cells, SNO non-keratinizing squamous epithelium cancer cells and HeLa cells after 48 h exposure. Compounds C9 inhibited cell proliferation to 50% of the vehicle-treated controls from 110 to 160 nm and C12 at concentrations ranging from 180 to 220 nm. Confocal microscopy revealed abnormal spindle morphology in mitotic cells. Cell cycle analysis showed an increase in the number of cells in the G(2) /M fraction after 24 h and an increase in the number of cell in the sub-G(1) fraction after 48 h, indicating that the compounds are antimitotic and able to induce apoptosis.

Influence of estradiol analogue on cell growth, morphology and death in esophageal carcinoma cells

2-Methoxyestradiol-bis-sulphamate is a bis-sulphamoylated derivative of the naturally occurring 17-beta-estradiol metabolite namely 2-methoxyestradiol. 2-Methoxyestradiol-bis-sulphamate is regarded as a potential anticancer drug with increased antiproliferative activity when compared to 2-methoxyestradiol. The aim of this pilot in vitro study was to determine the influence of 2-methoxyestradiol-bis-sulphamate on cell growth, morphology and possible induction of certain types of cell death in the SNO esophageal carcinoma cell line. A dose-dependent study (0.2-1.0 microM) was conducted with an exposure time of 24 hours. Data revealed that 2-methoxyestradiol-bis-sulphamate reduced cell numbers statistically significantly to 74% after exposure to 0.4 microM of the drug. Morphological studies including light microscopy demonstrated hallmarks of apoptosis, while fluorescent microscopy revealed both the presence of apoptosis and autophagy as types of cell death being induced in SNO cells after 24 hours of exposure to 0.4 microM 2-methoxyestradiol-bis-sulphamate.

In vitro effects of 2-methoxyestradiol-bis-sulphamate on cell growth, morphology and cell cycle dynamics in the MCF-7 breast adenocarcinoma cell line

In the search for new and improved anticancer therapies, researchers have identified several potentially useful compounds. One of these agents is 2-methoxyestradiol-bis-sulphamate (2ME-BM), a sulphamoylated derivative of 2-methoxyestradiol. The objective of this study was to evaluate 2ME-BM's in vitro efficacy as antiproliferative agent in the MCF-7 breast adenocarcinoma cell line. Light- and fluorescent microscopy showed decreased cell density, increased apoptotic characteristics and significant ultrastructural aberrations indicative of autophagic cell death after 24 hours of exposure at a concentration of 0.4 microM. In addition, mitotic indices revealed that 2ME-BM induces a G2M block. The latter was confirmed by flow cytometric analyses where increased sub-G1 and G2/M fractions, as well as an increase in cyclin B1 levels were observed. Further in vitro research into the mechanism of this potentially useful anticancer compound is thus warranted.

C2- and C4-position 17beta-estradiol metabolites and their relation to breast cancer

C2- and C4-position 17beta-estradiol metabolites play an important role in breast carcinogenesis. 2-Hydroxyestradiol and 4-hydroxyestradiol are implicated in tumorigenesis via two pathways. These pathways entail increased cell proliferation and the formation of reactive oxygen species that trigger an increase in the likelihood of deoxyribonucleic acid mutations. 2-Methoxyestradiol, a 17beta-estradiol metabolite, however, causes induction of apoptosis in transformed and tumor cells; thus exhibiting an antiproliferative effect on tumor growth. The 4-hydroxyestradiol:2-methoxyestradiol and 2-hydroxyestradiol:2-methoxyestradiol ratios therefore ought to be taken into account as possible indicators of carcinogenesis.

In vitro effects of 2-methoxyestradiol on cell numbers, morphology, cell cycle progression, and apoptosis induction in oesophageal carcinoma cells

The influence of 2-methoxyestradiol (2-ME) was investigated on cell numbers, morphology, cell cycle progression, and apoptosis induction in an oesophageal carcinoma cell line (WHCO3). Dose-dependent studies (1 x 10(-9)M-1 x 10(-6)M) revealed that 2-ME significantly reduced cell numbers to 60% in WHCO3 after 72 h of exposure at a concentration of 1 x 10(-6)M compared to vehicle-treated cells. Morphological studies entailing light-, fluorescent-, as well as transmission electron microscopy (TEM) confirmed 2-ME's antimitotic effects. These results indicated hallmarks of apoptosis including cell shrinkage, hypercondensation of chromatin, cell membrane blebbing, and apoptotic bodies in treated cells. Flow cytometric analyses demonstrated an increase in the G(2)/M-phase after 2-ME exposure; thus preventing cells from proceeding through the cell cycle. beta-tubulin immunofluorescence revealed that 2-ME caused spindle disruption. In addition, increased expression of death receptor 5 protein was observed further supporting the proposed mechanism of apoptosis induction via the extrinsic pathway in 2-ME-exposed oesophageal carcinoma cells.

Influence of 2-methoxyestradiol on MCF-7 cells: an improved differential interference contrasting technique and Bcl-2 and Bax protein expression levels

Proteins of the B-cell lymphoma 2 family are crucial for the regulation of apoptosis. B-cell lymphoma 2-associated X is a pro-apoptotic protein, while B-cell lymphoma 2 protein opposes apoptosis. The influence of 1 microM 2-methoxyestradiol was investigated on the expression levels of these two proteins in MCF-7 cells. 2-Methoxyestradiol exposure did not influence B-cell lymphoma 2 protein expression levels after 24 h of exposure. In contrast, B-cell lymphoma 2-associated X protein levels were significantly reduced. An improved differential interference contrasting technique revealed compromised cell density and the presence of a mitotic block in exposed cells. The study proposes that the influence of 2-methoxyestradiol on the expression of these proteins may be time- and cell type dependent and thus not evident during the mitotic block observed. Investigation of the regulation of the B-cell lymphoma 2 family will allow researchers to consider signaling pathways for diseases where apoptosis can potentially be controlled.

In vitro effects of 2-methoxyestradiol on MCF-12A and MCF-7 cell growth, morphology and mitotic spindle formation

The influence of 2-methoxyestradiol (2ME) was investigated on cell growth, morphology and spindle formation in a tumorigenic (MCF-7) and non-tumorigenic (MCF-12A) epithelial breast cell line. Inhibition of cell growth was more pronounced in the MCF-7 cells compared to the MCF-12A cells following 2ME treatment. Dose-dependent studies (10(-5)-10(-9) M) revealed that 10(-6) M 2ME inhibited cell growth by 44% in MCF-12A cells and by 84% in MCF-7 cells (p-value < 0.05). 2ME-treated MCF-7 cells showed abnormal metaphase cells, membrane blebbing, apoptotic cells and disrupted spindle formation. These observations were either absent or less prominent in MCF-12A cells. 2ME had no effect on the length of the cell cycle between S-phase and the time a mitotic peak was reached in either cell line but MCF-7 cells were blocked in mitosis with no statistically significant alterations in the phosphorylation status of Cdc25C. Nevertheless, Cdc2 activity was significantly increased in MCF-7 cells compared to MCF-12A cells (p-value < 0.05). The results indicate that 2ME disrupts mitotic spindle formation and enhances Cdc2 kinase activity, leading to persistence of the spindle checkpoint and thus prolonged metaphase arrest that may result in the induction of apoptosis. The tumorigenic MCF-7 cells were especially sensitive to 2ME treatment compared to the normal MCF-12A cells. Therefore, differential mechanism(s) of growth inhibition are evident between the normal and tumorigenic cells.

Hydroxyapatite-coated polyurethane for auricular cartilage replacement: an in vitro study

Auricular reconstruction remains a major challenge facing reconstructive surgeons owing to the complexity of autogenous transplants. In this study, the development of a three-dimensional custom-made polyurethane (PU) auricular implant with hydroxyapatite (HA) coating is described. The PU implant was produced by computerized tomography (CT) scanning and indirect rapid prototyping. To improve the physiological response of the implant, the PU prototype was coated with a microrough, homogenous layer of HA by a novel solvent-compression coating method. Bioactivity of the HA coated PU substrates was confirmed by apatite formation on the HA coating after 9 days in revised simulated body fluid (pH 7.4). Adhesion strength of the HA coating to the PU surface using the tensile pull-off test revealed partial failure of the coating with an average tensile strength of 1.6 MPa. As an initial stage indication of cytocompatibility for a soft tissue application, in vitro cell culturing on the HA-coated PU substrates using Graham 293 fibroblast cells was performed. After 24 and 72 h, the HA coated surfaces displayed significantly higher cell numbers and metabolically active cells compared with the virgin uncoated PU surfaces. This indicates that HA coated PU surfaces are cytocompatible towards fibroblasts and could potentially be applied to auricular cartilage tissue replacement.

Radiosensibilité intrinsèque et cassures double–brin de l'ADN dans les cellules humaines

Among the large spectrum of DNA damage induced by radiation, DNA double-strand breaks (DSBs) are considered, to date, as the key-lesions responsible for the cell killing. However, although it was always intuitive to radiobiologists, such a conclusion has only been reached after technical developments and conceptual advances and remains consensual rather than demonstrated formally. In this article, we have reviewed the results that have lead to the conclusion that the assessment of successful DSB repair can be the basis of reliable assays predictive of the clinical response to radiotherapy and some chemotherapeutic treatments. We have discussed a number of technical artifacts, the biases due to the extrapolation of data obtained in yeast and rodent model systems to the human situation and the variety of phenotypes observed in human cells and in particular: 1) the most recent techniques developed, based on immunofluorescence, which have revolutionized our understanding of the molecular events occurring early after irradiation but have also raised the crucial questions about the choice of techniques to assess DSB repair and their specificity for different steps of the repair process; 2) While the homologous recombination repair pathway is predominant in yeasts, its importance in human cells appears less obvious, and raises the problem that the existence of randomized repair events may produce many more errors in human cells than in small genome organisms; 3) the impairment of DSB repair is observed in a plethora of genetic diseases, leading to radiosensitivity, immunodeficiency and sometimes cancer-proneness, but the low frequency and the pleiotropism of such diseases makes difficult the development of a single predictive assay. Therefore, although complete DSB repair appears to be crucial for cell survival, further research is still needed to provide innovative techniques fro measuring repair which can be successfully transferred to the clinic and used to ensure the avoidance of deleterious side-effects to cancer therapies.

Influence of 2-methoxyestradiol on cell morphology and Cdc2 Kinase activity in WHCO3 esophageal carcinoma cells

The influence of 1 x 10(-6) M exogenous 2-methoxyestradiol (2ME) was investigated on nuclear and cytoplasmic morphology, as well as Cdc (cell division cycle) 2 kinase activity in WHCO3 esophageal carcinoma cells. Mitotic indices after 18 h of 2ME exposure revealed an increase in metaphase cells (9.0%) when compared to the vehicle-treated cells (0.9%). 2ME-treated cells showed apoptotic cells at 5.6% after 18 h of exposure to dimethyl sulphoxide, compared to 0.9% in vehicle-treated cells. Increased morphological characteristics of apoptosis were observed in 2ME-treated cells after 21.5 h of exposure. Twelve percent of cells were in apoptosis when compared to the 1.6% of vehicle-treated cells. Furthermore, 42.4% of cells were arrested in metaphase after 21.5 h of 2ME exposure compared to 2.9% of vehicle-control cells present in metaphase. Cdc2 kinase activity was statistically significantly increased (1.7-fold) (P < 0.005) after 18 h of 2ME exposure when compared to vehicle-treated controls. Although the mechanism of 2ME's action on esophageal carcinoma cells is not yet elucidated, the present study revealed that 2ME caused metaphase arrest, as well as an increase in Cdc2 kinase activity that culminated in the induction of apoptosis in these cells.

In vitro effects of 2-methoxyestradiol on cell morphology and Cdc2 Kinase activity in SNO oesophageal carcinoma cells

The effects of 1 x 10(-6) M exogenous 2-methoxyestradiol (2 ME) were determined on cell morphology and cell division cycle (Cdc) 2 kinase activity in SNO oesophageal carcinoma cells. Mitotic indices revealed an increase in metaphase cells (11.2%) when compared to the 0.5% vehicle-treated cells after 18 h of exposure to 2 ME. Vehicle-treated control cells did not show any hallmarks of apoptosis after 18 h of exposure to dimethyl sulphoxide. Only 0.5% of 2 ME-treated cells showed characteristics of apoptosis. Conversely, increased morphological hallmarks of apoptosis were observed in SNO-treated cells after 21.5 h of 2 ME exposure. When compared to the 0.5% in vehicle-treated cells, 4.7% of cells were in apoptosis. Furthermore, 34.1% of cells were blocked in metaphase after 21.5 h of 2 ME exposure compared to 0.6% of vehicle-control cells. In addition, Cdc2 kinase activity was statistically significantly increased (1.3-fold) (p<0.005) in 2 ME-treated cells when compared to vehicle-treated controls. The present preliminary study suggests that the accumulation observed in metaphase cells and the increase in Cdc2 kinase activity caused by 2 ME are consistent with morphological hallmarks of mitotic arrest and disrupted mitotic spindle formation, thus leading to induction of apoptosis in SNO cells.

Bax/Bcl-2 expression levels of 2-methoxyestradiol-exposed esophageal cancer cells

2-Methoxyestradiol (2ME), an endogenous metabolite of 17beta-estradiol, has been reported to play an active role in the induction of apoptosis in both proliferating endothelial and cancer cells. Since it has been indicated that an increased ratio of pro-apoptotic Bax protein to anti-apoptotic Bcl-2 protein expression can be associated with apoptosis, and since the exact action mechanism of 2ME is still not clearly defined and appears to vary according to cell type, the influence of 1 microM 2ME was investigated on Bax and Bcl-2 expression levels in squamous esophageal carcinoma cells. 2ME exposure led to statistically significant decreases (0.69 over DMSO controls) in Bcl-2 expression levels. In contrast, no statistically significant effects were observed on Bax expression levels after exposure to 2ME. The Bax/Bcl-2 ratio for 2ME-exposed cells was 1.45, normalised against Bcl-2 levels. Although the exact mechanisms of apoptosis induction in squamous esophageal cancer cells require further investigation, the present study suggests that this altered ratio in favor of Bax could lead to the induction of apoptosis in these cells.

Influence of prostaglandin A2 on Bax, Bcl-2 and PCNA expression in MCF-7 cells

The effects of 20 microg/mL exogenous prostaglandin A(2) (PGA(2)) were determined on Bax, Bcl-2 and proliferating cell nuclear antigen (PCNA) expression levels in MCF-7 cells. Flow cytometric analysis indicated a pronounced increase in the S phase and a decrease in the G(1) phase, whereas a significant increase in the DNA content preceding the G(0)/G(1) peak was also observed after 48 h of exposure to PGA(2). Confirmation of apoptosis was determined after 12 h, 36 h and 48 h of PGA(2) exposure employing the mitosensor reagent that detects potential changes in the mitochondrial membrane. Twenty-eight percent of PGA(2)-exposed cells were in apoptosis when compared to the 7.1% vehicle-treated cells after 48 h. PGA(2) exposure led to statistically significant increase (1.25-fold) over vehicle-treated controls in Bax expression levels. Decreases in Bcl-2 (0.79-fold), as well as PCNA (0.69-fold) expression levels over vehicle-treated controls were observed. The Bax/Bcl-2 ratio for PGA(2)-exposed cells was 2.7. The present study suggests that an accumulation in the S phase, a decrease in expression levels of PCNA, as well as an altered ratio in favor of Bax, could lead to the induction of apoptosis in these cells.

Influence of prostaglandin A2 and 2-methoxyestradiol on Bax and Bcl-2 expression levels in cervical carcinoma cells

Proteins of the Bcl-2 family are key regulators of apoptosis. Bax can be regarded as pro-apoptotic, whereas Bcl-2 is perceived as anti-apoptotic. It has been proposed that an increased ratio of pro-apoptotic Bax to anti-apoptotic Bcl-2 can be associated with apoptosis. Since prostaglandin A2 (PGA2) and 2-methoxyestradiol (2-ME) play an active role in the induction of apoptosis, the influence of 20 microg/ml PGA2 and 1 microM 2-ME was investigated on Bax and Bcl-2 expression levels in cervical carcinoma cells. Both PGA2 and 2-ME exposure led to statistically significant increases in Bax expression levels. Cells were shown to be more susceptible to the effects of 2-ME than to the effects caused by PGA2. In contrast, no statistically significant effects were observed on Bcl-2 expression levels after exposure to PGA2 and 2-ME. The Bax/Bcl-2 ratios for PGA2- and 2-ME-exposed cells were 2.06 and 1.87 respectively, normalised against Bcl-2 levels. Further investigation of the function and regulation of the Bcl-2 family will allow researchers to consider potential pathways of apoptosis signaling mechanisms for diseases where apoptosis can potentially be controlled.

Evaluation of clinical teaching and professional development in a problem and community-based nursing module

In South Africa the main focus is on primary health care. This affects the education and training of nurses, and training schools must respond by developing appropriate teaching modules. A school of nursing developed, implemented and revised a problem- and community- based learning module over a period of three years (1996-1998). This student-centered module focuses on students’ needs, active participation, collaboration, accountability, self-assessment, self-study, life-long learning and appropriate skills. In the formal clinical teaching environment PBL was the main approach. However, this approach was also supported by a variety of strategies, for example group discussions and scenarios. The knowledge, attitudes and professional development skills acquired in the PBL approach were then applied informally in the community setting (CBE). The purpose of the study was to evaluate a first year clinical teaching module as part of an extensive programme. A quantitative research method, a descriptive design, and a variety of data collection techniques were used. Conclusions were that clinical teaching was effective within the problem- (PBL) and community-based (CBE) approaches; 78% of respondents were positive about the clinical learning environment; 61 % stated that expectations were met; 81% preferred group activities, and 67% indicated that they had developed professional skills. Facilitators agreed that clinical teaching met the requirements of PBL & CBE. The pass rate also improved.

Synchrotron radiation-based experimental determination of the optimal energy for cell radiotoxicity enhancement following photoelectric effect on stable iodinated compounds

This study was designed to experimentally evaluate the optimal X-ray energy for increasing the radiation energy absorbed in tumours loaded with iodinated compounds, using the photoelectric effect. SQ20B human cells were irradiated with synchrotron monochromatic beam tuned at 32.8, 33.5, 50 and 70 keV. Two cell treatments were compared to the control: cells suspended in 10 mg ml⁻¹ of iodine radiological contrast agent or cells pre-exposed with 10 μM of iodo-desoxyuridine (IUdR) for 48 h. Our radiobiological end point was clonogenic cell survival. Cells irradiated with both iodine compounds exhibited a radiation sensitisation enhancement. Moreover, it was energy dependent, with a maximum at 50 keV. At this energy, the sensitisation calculated at 10% survival was equal to 2.03 for cells suspended in iodinated contrast agent and 2.60 for IUdR. Cells pretreated with IUdR had higher sensitisation factors over the energy range than for those suspended in iodine contrast agent. Also, their survival curves presented no shoulder, suggesting complex lethal damages from Auger electrons. Our results confirm the existence of the 50 keV energy optimum for a binary therapeutic irradiation based on the presence of stable iodine in tumours and an external irradiation. Monochromatic synchrotron radiotherapy concept is hence proposed for increasing the differential effect between healthy and cancerous tissue irradiation.

2-methoxyestradiol strongly inhibits human uterine sarcomatous cell growth

OBJECTIVES

The objective was to test the hypothesis that uterine sarcomatous cells are hormone-sensitive. We included 2-methoxyestradiol, an endogenous metabolite of estradiol with antiproliferative properties.

METHODS

Proliferation assays assessed the effects of estradiol, progesterone, tamoxifen, raloxifen, [D-Trp(6)]leuteinizing hormone-releasing hormone (LHRH), ICI 182,780 (faslodex or fulvestrant), and 2-methoxyestradiol on cell growth of a cell line derived from uterine carcinosarcoma, but consisting solely of mesenchymal cells (SK-UT-1). Morphological changes of SK-UT-1 cells after exposure to 2-methoxyestradiol were evaluated and fluorescence immunohistochemistry for tubulin was used to detect changes in the mitotic spindle. Flow cytometry was used to assess the influence of 2-methoxyestradiol on the SK-UT-1 cell cycle as well as the role of p53 in apoptosis.

RESULTS

Cell proliferation analysis revealed that SK-UT-1 cells were stimulated by progesterone, tamoxifen, and [D-Trp(6)]LHRH. Cells were insensitive to estradiol, raloxifen, and ICI 182,780. Inhibition occurred after exposure to 2-methoxyestradiol and was accompanied by a threefold increase in the G2/M population, with a concomitant decrease in the G1 population, as shown by cell cycle analysis. SK-UT-1 cells exposed to 2-methoxyestradiol showed morphological changes indicative of apoptosis. Examination of signaling pathways that mediate 2-methoxyestradiol-induced apoptosis showed p53-independent growth inhibition. The inhibition of SK-UT-1 cell growth by arresting the cells during G2/M progression could be attributed to interference with the microtubule system, as determined by fluorescence immunohistochemistry.

CONCLUSIONS

The stimulatory effect of progesterone, tamoxifen, and [D-Trp(6)]LHRH suggests that uterine sarcomatous cells are hormone-sensitive. Our finding that 2-methoxyestradiol-mediated growth inhibition of uterine sarcomatous cells occurred in a p53-independent manner may have considerable clinical significance. The inadequate armature against uterine sarcomas and the limited toxicity of 2-methoxyestradiol may render these observations especially important.

Lack of cell death enhancement after irradiation with monochromatic synchrotron X rays at the K-shell edge of platinum incorporated in living SQ20B human cells as cis-diamminedichloroplatinum (II)

In this paper we describe the results of experiments using synchrotron radiation to trigger the Auger effect in living human cancer cells treated with a widely used chemotherapy drug: cis-diamminedichloroplatinum (II) (cisplatin). The experiments were carried out at the ID17 beamline of the European Synchrotron Radiation Facility, which produces a high-fluence monochromatic beam that is adjustable from 20 to 80 keV. Cisplatin was chosen as the carrier of platinum atoms in the cells because of its alkylating-like activity and the irradiation was done with monochromatic beams above and below the platinum K-shell edge (78.39 keV). Cell survival curves were comparable with those obtained for the same cells under conventional irradiation conditions. At a low dose of cisplatin (0.1 microM, 48 h), no difference was seen in survival when the cells were irradiated above and below the K-shell edge of platinum. Higher cisplatin concentrations were investigated to enhance the cellular platinum content. The results with 1 microM cisplatin for 12 h showed no difference when the cells were irradiated with beams above or below the platinum K-shell edge with the exception of the higher cell death resulting from drug toxicity. The intracellular content of platinum was significant, as measured macroscopically by inductively coupled plasma mass spectrometry. Its subcellular localization and particularly its presence in the cell nucleus were verified by microscopic synchrotron X-ray fluorescence. This was the first known attempt at K-shell edge photon activation of stable platinum in living cells with a platinum complex used for chemotherapy. Its evident toxicity in these cells leads us to put forth the hypothesis that cisplatin toxicity can mask the enhancement of cell death induced by the irradiation above the K-shell edge. However, K-shell edge photon activation of stable elements provides a powerful technique for the understanding of the biological effects of Auger processes. Further avenues of development are discussed.

[Retrospective study of hospitalizations for heart failure in elderly patients in a cardiology service of a general hospital center]

The results of a retrospective study of patients over 70 years of age admitted to the cardiology department of Meaux Hospital for cardiac failure in 1997 are reported. The cases of 143 patients were analysed with respect to two age groups: 70-79 years, and over 80 years of age. The principal aetiology of cardiac failure in all ages was ischaemic heart disease. Hypertensive heart disease was observed in younger patients and valvular heart disease in the more elderly. No significant gender differences were observed in those affected by this pathology or by left ventricular systolic or diastolic dysfunction between the younger and older patients, men having more systolic dysfunction than women. The main causal factor of decompensation in all ages was supraventricular arrhythmias. From the therapeutic point of view, the prescription of ACE inhibitors was relatively common but at low doses. Re-hospitalisation for cardiac failure was common and observed mainly in patients with low ejection fractions. The average hospital stay was 12.58 days. The hospital mortality was high: 15%. Two year survival was 41% with no difference between patients with systolic or diastolic dysfunction. Pluridisciplinary management should reduce the number of re-hospitalisation, improve the quality of life and, perhaps, improve survival.

The effect of the menstrual cycle on the pharmacokinetics of caffeine in normal, healthy eumenorrheic females

OBJECTIVE

Hormonal fluctuations of estrogen and progesterone in eumenorrheic women may be capable of altering the pharmacokinetics of certain agents. The objective of this study was to determine the effect of the luteal, ovulatory and follicular phases of the menstrual cycle on the pharmacokinetics of caffeine, a low clearance, flow-independent drug.

METHODS

Subjects were ten healthy, non-smoking, eumenorrheic females who were not pregnant and had not used oral contraceptives for a minimum of 3 months prior to the study. Blood samples were collected during one menstrual cycle for the determination of estradiol and progesterone concentrations during the follicular (days 2-6 post-onset of menses), ovulatory (days 13-16 post-onset of menses) and luteal (days 22-26 post-onset of menses) phases. Caffeine was administered over a single menstrual cycle during the follicular, ovulatory and luteal phases. Each subject was administered a single oral dose of caffeine (300 mg) in 100 ml of lemonade during each phase of the menstrual cycle. A venous catheter was used to collect blood samples at pre-dose and at the following time points: 0.25, 0.5, 0.75, 1, 1.5, 2, 4, 6, 8, 10, 12 and 24 h. Plasma caffeine concentrations were determined using a validated ultraviolet high-performance liquid chromatography method.

RESULTS

There were no significant (P < 0.05) differences in the pharmacokinetic parameters of caffeine across the menstrual cycle phases. The average area under the plasma concentration-time curve (AUCinf) was 93.01 mg 1(-1) x h and the absorption rate constant (ka) was 2.88 h(-1) during the ovulatory phase, 83.0 mg 1(-1) h and 2.06 h(-1), respectively, during the luteal phase and 84.7 mg 1(-1) x h and 1.84 h(-1), respectively, during the follicular phase.

CONCLUSIONS

These findings suggest that the menstrual cycle does not significantly alter the pharmacokinetics of caffeine.

A formative model for student nurse development and evaluation--Part 1--Developing the model

Preparing student nurses for the profession is a complex task for nurse educators; especially when dealing with the development of personal and interpersonal skills, qualities and values held in high esteem by the nursing profession and the community they serve. These researchers developed a model for formative evaluation of students by using the principles of inductive and deductive reasoning. This model was implemented in clinical practice situations and evaluated for its usefulness. It seems that the model enhanced the standards of nursing care because it had a positive effect on the behavior of students and they were better motivated; the model also improved interpersonal relationships and communication between practising nurses and students. The fact that students repeatedly use the model as a norm for self evaluation ensures that they are constantly reminded of the standards required of a professional nurse.