Impact of compliance to chemoradiation on long-term outcomes in squamous cell carcinoma of the anus: results of a post hoc analysis from the randomised phase III ACT II trial.

BACKGROUND: Concurrent chemoradiation is standard-of-care for patients with squamous cell carcinoma of the anus. Poor compliance to chemotherapy, radiotherapy treatment interruptions and unplanned breaks may impact adversely on long-term outcomes. METHODS: The ACT II trial recruited 940 patients with localised squamous cell carcinoma of the anus, and assigned patients to mitomycin (week 1) or cisplatin (weeks 1 and 5), with fluorouracil (weeks 1 and 5) and radiotherapy (50.4 Gy in 28 fractions over 38 days). This post hoc analysis examined the association between baseline factors (age, gender, site, T stage and N stage), and compliance to treatment (radiotherapy and chemotherapy), and their effects on locoregional failure-free survival, progression-free survival (PFS) and overall survival (OS). Compliance was categorised into groups. Radiotherapy: six groups according to total dose and overall treatment time (OTT). Chemotherapy: three groups (A = per-protocol; B = dose reduction or delay; C = omitted). RESULTS: A total of 931/940 patients were assessable for radiotherapy and 936 for chemotherapy compliance. Baseline glomerular filtration rate <60 ml/min and cisplatin were significantly associated with poor week 5 compliance to chemotherapy (P = 0.003 and 0.02, respectively). Omission of week 5 chemotherapy was associated with significantly worse locoregional failure-free survival [hazard ratio (HR) 2.53 (1.33-4.82) P = 0.005]. Dose reductions/delays or omission of week 5 chemotherapy were associated with significantly worse PFS {HR: 1.56 [95% confidence interval (CI): 1.18-2.06], P = 0.002 and HR: 2.39 (95% CI: 1.44-3.98), P = 0.001, respectively} and OS [HR: 1.92 (95% CI: 1.41-2.63), P < 0.001 and HR: 2.88 (95% CI: 1.63-5.08), P < 0.001, respectively]. Receiving the target radiotherapy dose in >42 days is associated with worse PFS and OS [HR: 1.72 (95% CI: 1.17-2.54), P =0.006]. CONCLUSION: Poor compliance to chemotherapy and radiotherapy were associated with worse locoregional failure-free survival, PFS and OS. Treatment interruptions should be minimised, and OTT and total dose maintained. CLINICAL TRIAL NUMBER: ISRCTN 26715889.

Prediction of medication non-adherence and associated outcomes in pediatric kidney transplant recipients.

Studies have continued to evaluate risk factors associated with post-transplant non-adherence in pediatric patients. However, many of these studies fail to evaluate how risk factors can be utilized to predict MNA. The aims of this study were to (i) determine salient risk factors associated with MNA to develop an adequate predictive risk model and (ii) assess transplant outcomes based on the presence of MNA in a large, diverse cohort of pediatric KTX recipients. One hundred and seventy-five solitary pediatric KTX recipients transplanted from 1999 to 2013 were included. AA, males, older patients, those who lived in urban environments, had legal issues, and lived shorter distances from the transplant center were more likely to have MNA. Using logistic regression, a parsimonious model applying nine risk factors together was developed for predicting MNA, demonstrating a PPV of 69% and a NPV of 81%. Patients with MNA had more than twice the risk of biopsy proven acute rejection, 1.6 times the risk of hospitalization, and 1.8 times the risk of graft loss. Utilization of a predictive model to determine risk of MNA after pediatric KTX may offer clinicians the ability to efficiently and effectively monitor MNA following transplant.

Chronicle: results of a randomised phase III trial in locally advanced rectal cancer after neoadjuvant chemoradiation randomising postoperative adjuvant capecitabine plus oxaliplatin (XELOX) versus control.

BACKGROUND: In stage III colon cancer, oxaliplatin/5-fluorouracil (5-FU)-based adjuvant chemotherapy (FOLFOX) improves disease-free survival (DFS) and overall survival (OS). In rectal adenocarcinoma following neoadjuvant chemoradiation (CRT), we examined the benefit of postoperative adjuvant capecitabine and oxaliplatin (XELOX) chemotherapy. METHODS: Eligible patients were randomly assigned following fluoropyrimidine-based CRT and curative resection to observation or six cycles of XELOX. The primary end point was DFS; secondary end points were acute toxicity and OS. 390 patients were required in each arm, to detect an improvement in 3-year DFS from 40% to 50.5%, with 85% power and two-sided 5% significance level. RESULTS: The study closed prematurely in 2008 because of poor accrual. Only 113 patients were randomly assigned to either observation (n = 59) or XELOX (n = 54). Compliance was poor, 93% allocated chemotherapy started and 48% completed six cycles. Protocolised dose reductions in XELOX were 39%, and levels of G3/G4 toxicity 40%. After a median follow-up of 44.8 months, 16 patients (27%) in the observation arm had relapsed or died compared with 12 patients (22%) in XELOX. The 3-year DFS rate was 78% with XELOX and 71% with observation [hazard ratio (HR) for DFS = 0.80; 95% confidence interval (CI) 0.38-1.69; P = 0.56]. The 3-year OS for XELOX and observation were 89% and 88%, respectively (HR for OS = 1.18; 95% CI 0.43-3.26; P = 0.75). CONCLUSIONS: The observed improvement in DFS for adjuvant XELOX and similar OS were not statistically significant, as expected given the small number of patients and consequent low power. Our findings support the need for trials that test the role of neoadjuvant chemotherapy. CLINICALTRIALSGOV IDENTIFIER: NCT00427713.

Tumour- and treatment-related colostomy rates following mitomycin C or cisplatin chemoradiation with or without maintenance chemotherapy in squamous cell carcinoma of the anus in the ACT II trial.

BACKGROUND: Squamous cell carcinoma of the anus (SCCA) is highly sensitive to chemoradiation (CRT) which achieves good loco-regional control and preserves anal function. However, some patients require permanent stoma formation either as a result of surgery on relapse, poor anal function or treatment-related symptoms. Our aim was to determine patient, tumour and treatment-related colostomy rates following CRT and maintenance chemotherapy in the ACT II trial. PATIENTS AND METHODS: The ACT II trial recruited 940 patients comparing 5FU-based CRT using cisplatin (CisP) or mitomycin C (MMC) with or without additional maintenance chemotherapy. We investigated the association between colostomy-free survival (CFS) and progression-free survival (PFS) with age, gender, T-stage, N-stage, treatment and baseline haemoglobin. RESULTS: The median follow-up was 5.1 years (n = 884 evaluable/940); tumour site canal (84%), margin (14%); stage T1/T2 (52%), T3/T4 (46%); N+ (32%), N0 (62%). Twenty out of 118 (17%) colostomies fashioned before CRT were reversed within 8 months. One hundred and twelve patients had a post-treatment colostomy due to persistent disease (98) or morbidity (14). Fifty-two per cent (61/118) of all pre-treatment colostomies were never reversed. The 5-year CFS rates were 68% MMC/Maint, 70% CisP/Maint, 68% MMC/No-maint and 65% CisP/No-maint. CRT with CisP did not improve CFS when compared with MMC (hazard ratio: 1.04, 95% confidence interval: 0.82-1.31, P = 0.74). The 5-year CFS rates were higher for T1/T2 (79%) than T3/T4 (54%) tumours and higher for node-negative (72%) than node-positive (60%) patients. Significant predictors of CFS were gender, T-stage and haemoglobin, while treatment factors had no impact on outcome. Similar associations were found between PFS and tumour/treatment-related factors. CONCLUSIONS: The majority (52%) of pre-treatment colostomies were never reversed. Neither CRT with 5FU/CisP nor maintenance chemotherapy impacted on CFS. The low risk of colostomy for late effects (1.7%) is likely to be associated with the modest total radiotherapy dose. The predictive factors for CFS were T-stage, gender and baseline haemoglobin. CLINICAL TRIAL REGISTRATION NUMBER: ISRCTN 26715889.

Improving transplant patient safety through pharmacist discharge medication reconciliation.

Greater than 50% of medication errors are estimated to occur during transitions of care, and solid-organ transplant recipients are at an increased risk for errors due to significant changes in their medication regimen following transplantation. This prospective, observational study with a historical control group was conducted to evaluate the discharge process for transplant recipients and determine if transplant pharmacist involvement would improve safety. During the prospective period, a total of 191 errors were made on discharge medication reconciliations (n = 64, mean rate 3.0 per patient); however, pharmacists prevented 119 of these errors (1.9 errors per patient). In the retrospective period, none of the 430 errors identified were prevented at the time of discharge (n = 128, p < 0.0001). The 72 errors not prevented at the time of discharge in the prospective cohort were identified by the pharmacist at the patient's first clinic visit (1.1 errors per patient). In the historical cohort, all 430 errors made at discharge persisted until at least the time of the first clinic visit (3.4 errors per patient, p < 0.0001). This study demonstrates that transplant recipients are at a high risk for medication errors and that transplant pharmacist involvement leads to improved safety through the significant reduction of medication errors.

Chemoradiation for the treatment of epidermoid anal cancer: 13-year follow-up of the first randomised UKCCCR Anal Cancer Trial (ACT I).

BACKGROUND: The first UKCCCR Anal Cancer Trial (1996) demonstrated the benefit of chemoradiation over radiotherapy (RT) alone for treating epidermoid anal cancer, and it became the standard treatment. Patients in this trial have now been followed up for a median of 13 years. METHODS: A total of 577 patients were randomised to receive RT alone or combined modality therapy using 5-fluorouracil and mitomycin C. All patients were scheduled to receive 45 Gy by external beam irradiation. Patients who responded to treatment were recommended to have boost RT, with either an iridium implant or external beam irradiation. Data on relapse and deaths were obtained until October 2007. RESULTS: Twelve years after treatment, for every 100 patients treated with chemoradiation, there are an expected 25.3 fewer patients with locoregional relapse (95% confidence interval (CI): 17.5-32.0 fewer) and 12.5 fewer anal cancer deaths (95% CI: 4.3-19.7 fewer), compared with 100 patients given RT alone. There was a 9.1% increase in non-anal cancer deaths in the first 5 years of chemoradiation (95% CI +3.6 to +14.6), which disappeared by 10 years. CONCLUSIONS: The clear benefit of chemoradiation outweighs an early excess risk of non-anal cancer deaths, and can still be seen 12 years after treatment. Only 11 patients suffered a locoregional relapse as a first event after 5 years, which may influence the choice of end points in future studies.

Structure of the gene encoding a putative Schistosoma mansoni tegumental antigen precursor.

In order to obtain the complete gene encoding the putative precursor of a 15-kDa Schistosoma mansoni tegumental antigen (Sm15), two cDNAs (A70 and A184) and two fragments of independent genomic clones were subcloned and sequenced. The collated sequence contains 4700 nucleotides and represents the full length open reading frame of the gene, encoding a protein of 1032 amino acids with a calculated molecular mass of 116,900. Thus, the gene encodes a much longer protein than that identified in the tegumental membranes, suggesting that it encodes a precursor that is subsequently highly processed. A 964-bp region composed of 5 closely related repeats was found to be present within the translated frame. The predicted protein is highly acidic and there is no indication of hydrophobic domains that may represent transmembrane regions or indicate attachment of a GPI anchor. The coding region has no homologies in the currently available data bases. In the 5' non-transcribed area a copy of the SM alpha repeat family is present. The coding region is preceded by putative CCAAT and TATA boxes that may be involved in the control of expression.

Predicted structure of a major Schistosoma mansoni eggshell protein.

The complete sequence for a major Schistosome mansoni eggshell protein gene has been determined from a genomic DNA fragment. The use of an open reading frame encoding a glycine-rich polypeptide was confirmed by in vitro translation of schistosome mRNA in the presence of [3H]glycine and comparison with the amino acid composition of purified, schistosome eggshells. Apart from the extraordinary abundance of glycine and tyrosine which are evenly distributed throughout the polypeptide chain, the most striking features of the deduced amino acid sequence are the presence of five well-conserved tandem repeats of 16-18 residues in the N-terminal region and the asymmetrical distribution of charged residues. Acidic residues (Asp) are confined to the N-terminal region, while basic residues (Lys, His), with the exception of a single histidine, are found in the C-terminal region. A model structure composed of short anti-parallel beta-strands is proposed, in which glycines and residues with small side chains lie within the strands and tyrosines and cysteines are arranged at the bends, where they would be available for cross-linking. Four such strands form one of the tandem repeats which are predicted in turn to form a stack of five closely packed beta-sheets, each of three strands and linked by the more variable fourth strand. The C-terminal region may form a similar but less compact structure. The ordered structure demonstrated by birefringence studies of the schistosome eggshell [Kusel, J. (1970) Parasitology 60, 79-88] could be formed by packing of the polypeptides such that the N-terminal domain contributes counter ions or cross-links to the C-terminal domain of adjacent molecules.

Structure of Sm25, an antigenic integral membrane glycoprotein of adult Schistosoma mansoni.

Sm25 is the principal antigen recognised by antibodies from mice protectively vaccinated with isolated tegumental membranes of adult Schistosoma mansoni. The full-length amino acid sequence of this protein has been deduced from the sequence of two cDNAs, one isolated by screening a cDNA library and the other, including the 5' end of the gene, amplified directly from adult worm RNA using the polymerase chain reaction. The predicted sequence represents a nascent polypeptide of Mr 21,500. Following cleavage of a predicted signal sequence, the Mr of the resulting polypeptide is 17,600. The polypeptide contains 2 potential sites for N-linked glycosylation and a hydrophobic domain at the C-terminus that could facilitate membrane association. Analysis of the mature gene product confirmed that Sm25 is an N-glycosylated integral membrane protein and that the Mr of the deglycosylated polypeptide is between 15,000 and 20,000.

Functional characterisation of human TASK-3, an acid-sensitive two-pore domain potassium channel.

Human TASK-3 (hTASK-3) is a recently identified member of the two-pore domain potassium channel (2PDKC) family which in man is predominantly expressed in the cerebellum. Previous preliminary examination of this channel indicates that when expressed in Xenopus oocytes, it produces a K(+) selective background conductance and consequent shift in resting membrane potential, thus mimicking other 2PDKC. Here we describe some additional functional and pharmacological aspects of hTASK-3-mediated conductances expressed in both Xenopus oocytes and HEK293 cells. hTASK-3 expression produces steady-state currents that approximate Goldman--Hodgkin--Katz behaviour with respect to membrane potential. Despite this, voltage steps from -80 mV to potentials > approximately -20 mV induce currents that exhibit a clear time-dependent increase in current amplitude. Kinetically, this increase in current was well fit by a single exponential, the time constant of which was approximately 10 ms and appeared independent of test potential, between -20 and +80 mV. In HEK293 cells hTASK-3 currents were inhibited by extracellular acidosis with a mid-point for inhibition of pH 6.4. Furthermore, the activity of TASK-3 was potentiated by the volatile anaesthetic halothane but inhibited by the local anaesthetic bupivacaine.

Distribution and expression of TREK-1, a two-pore-domain potassium channel, in the adult rat CNS.

TREK-1 is a member of the two-pore-domain potassium channel family which is expressed predominantly in the CNS. Using an anti-peptide polyclonal antiserum, we have determined the distribution of TREK-1 in the brain and spinal cord of adult rats. Specificity of the antiserum was tested using a TREK-1-transfected cell line and confirmed with c-myc-tagged TREK-1. In thin tissue sections, immunoreactivity was widespread throughout the rat brain and spinal cord. TREK-1-like signals were observed in the cerebral cortex, basal ganglia, hippocampus, and various other subcortical nuclei in the hypothalamus, thalamus, mesencephalon and rhombencephalon. TREK-1 labelling appeared to be over the entire cell membrane, including the cell body and processes. Cells that morphologically resembled projection neurones and interneurones but not glial cells were labelled. As interneurones and known GABAergic projection neurones were the predominant population labelled, we investigated the possibility that TREK-1 is expressed in GABA-containing neurones using a specific anti-GABA antiserum. Expression of TREK-1 in GABA-containing neurones was observed in a number of areas, including the isocortex, hippocampus and thalamus. Thus, TREK-1 expression defines a unique and specific subset of interneurones and principal cells. These studies indicate a widespread distribution of TREK-1 potassium channels throughout the rat brain and spinal cord, with expression in a number of areas being demonstrated to be present on GABA-containing neurones.

Effect of SB-205384 on the decay of GABA-activated chloride currents in granule cells cultured from rat cerebellum.

1. 4-Amino-7-hydroxy-2-methyl-5,6,7,8,-tetrahydrobenzo[b]thieno[2,3-b]pyrid ine-3-carboxylic acid, but-2-ynyl ester (SB-205384) and other gamma-aminobutyric acid(A) (GABA(A)) receptor modulators were tested for their effects on GABA-activated chloride currents in rat cerebellar granule cells by use of the whole-cell patch clamp technique. 2. The major effect of SB-205384 on GABA(A)-activated current was an increase in the half-life of decay of the response once the agonist had been removed. This is in contrast to many GABA(A) receptor modulators that have previously been shown to potentiate GABA-activated currents. 3. This profile could be explained if SB-205384 stabilizes the channel in open and desensitized states so that channel closing is dramatically slowed. Such a modulatory profile may produce a novel behavioural profile in vivo.

SB-205384: a GABA(A) receptor modulator with novel mechanism of action that shows subunit selectivity.

1. SB-205384, and its (+) enantiomer (+)-SB-205384 were tested for their modulatory effects on human GABA(A) receptor subunit combinations expressed in Xenopus oocytes by electrophysiological methods. 2. The slowing of the decay rate induced by SB-205384 on native GABA-activated currents in rat neurones was also seen on GABA(A) currents in oocytes expressing human GABA(A) subunits. This temporal effect was observed for the alpha3beta2gamma2 subunit combination with little effect in subunit combinations containing either alpha1 or alpha2. 3. Potentiation of the peak amplitude of the GABA-activated currents by SB-205384 or (+)-SB-205384 was less specific for a particular subunit combination, although the greatest effect at 10 microM drug was seen on the alpha3beta2gamma2 subunit combination. 4. In contrast, zolpidem, a benzodiazepine site modulator, did not significantly slow decay rates of GABA(A) currents in oocytes expressing the alpha3beta2gamma2 subunit combination. Zolpidem, as expected, did selectively potentiate GABA-activated currents on oocytes expressing the gamma2 subunit compared to those containing the gamma1. 5. The results show that the novel kinetic modulatory profile of SB-205384 is selective for the alpha3beta2gamma2 subunit combination. This suggests that the compound is binding to a novel regulatory site on the subunit complex.

Distribution analysis of human two pore domain potassium channels in tissues of the central nervous system and periphery.

Potassium channels are amongst the most heterogeneous class of ion channels known and are responsible for mediating a diverse range of biological functions. The most recently described family of K+ channels, the 'two pore-domain family', contain four membrane spanning domains and two pore-forming domains, suggesting that two channel subunits associate to form a functional K+ pore. Several sub-families of the two pore domain potassium channel family have been described, including the weakly inward rectifying K+ channel (TWIK), the acid-sensitive K+ channel (TASK), the TWIK-related K+ channel (TREK) and the TWIK-related arachidonic acid stimulated K+ channel (TRAAK). However, comparison of the mRNA expression of these channels has been difficult due to the differences in methods used and the species studied. In the present study, we used a single technique, TaqMan semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), to investigate the mRNA distribution of all currently known two pore potassium channels in human central nervous system (CNS) and peripheral tissues. TWIK-1 and the TWIK-1-like channel KCNK7 were predominantly expressed in the CNS, in contrast to TWIK-2 which was preferentially expressed in peripheral tissues such as pancreas, stomach, spleen and uterus. TASK-1 was expressed in the CNS and some peripheral tissues, whereas TASK-2 was exclusively expressed in the periphery except for mRNA expression observed in dorsal root ganglion and spinal cord. In addition, mRNA expression of the recently identified TASK-3, was almost completely exclusive to cerebellum with little or no mRNA detected in any other tissues. TREK-1 and TRAAK mRNA expression was predominantly CNS specific in contrast to the closely related TREK-2, which was expressed in both CNS and peripheral tissues. Studying the mRNA expression profiles of known two pore domain K+ channels will aid in the understanding of the biological roles of these channels. Furthermore, identification of common areas of expression may help identify which channels, if any, associate to form heteromeric K+ channel complexes.

Cloning, localisation and functional expression of a novel human, cerebellum specific, two pore domain potassium channel.

We have isolated, by degenerate PCR, a complementary DNA encoding a novel two pore domain potassium channel. This is the 7th functional member of the human tandem pore domain potassium channel family to be reported. It has an open reading frame of 1.125 kb and encodes a 374 amino acid protein which shows 62% identity to the human TASK-1 gene: identity to other human members of the family is 31-35% at the amino acid level. We believe this gene to be human TASK-3, the ortholog of the recently reported rat TASK-3 gene: amino acid identity between the two is 74%. 'Taqman' mRNA analysis demonstrated a very specific tissue distribution pattern, showing human TASK-3 mRNA to be localised largely in the cerebellum, in contrast rat TASK-3 was reported to be widely distributed. We have shown by radiation hybrid mapping that human TASK-3 can be assigned to chromosome 8q24.3. Human TASK-3 was demonstrated to endow Xenopus oocytes with a negative resting membrane potential through the presence of a large K(+) selective conductance. TASK-3 is inhibited by extracellular acidosis with a mid-point of inhibition around pH 6. 5, supporting the predictions from the sequence data that this is a third human TASK (TWIK-related acid sensitive K(+) channel) gene.

The neuroprotective agent sipatrigine (BW619C89) potently inhibits the human tandem pore-domain K(+) channels TREK-1 and TRAAK.

We have cloned and functionally expressed the human orthologue of the mouse TRAAK gene. When cDNA for hTRAAK is expressed in either Xenopus oocytes or HEK293 cells it forms a K(+)-selective conductance and hyperpolarises the resting membrane potential. Quantitative mRNA expression analysis using Taqman revealed that hTRAAK mRNA is predominantly present in the central nervous system where it exhibits a regionally diverse pattern of expression. Like the related channel TREK-1, the activity of TRAAK was potentiated by arachidonic acid. The neuroprotective agent sipatrigine (10 microM) inhibited both hTREK-1 (73.3+/-4.4%) and hTRAAK (45.1+/-11.2%) in a reversible, voltage-independent manner. Inhibition of both channels was dose-dependent and for TREK-1 occurred with an IC(50) of 4 microM. The related compound lamotrigine, which is a better anticonvulsant but weaker neuroprotective agent than sipatrigine, was a far less effective antagonist of both channels, producing <10% inhibition at a concentration of 10 microM.

Site-specific splice variation of the human P2X4 receptor.

P2X4 receptors are expressed in specific brain areas. We now describe site-specific splice variations of the human P2X4 receptor subunit, occurring at residue [YVIG / WVFV(W)] near the end of the first predicted transmembrane domain. p2X4(b) is formed by the insertion of an additional 16 amino acids. p2X4(C) is formed by deleting a cassette of 130 amino acids, including six of the 10 conserved extracellular cysteine residues. Transfection of P2X4(a), but not p2x4(c), formed functional channels in Xenopus oocytes and human 1321N1 cells. After transfection of p2X4(b) small, inconsistent ATP-evoked responses were detected only in the human cells, but when co-expressed, p2x4(b) may alter the function of P2X4(a) in oocytes. The distribution of splice variant RNA within human brain suggests regionally-dependent expression. These data indicate that the functions of the human P2X4 receptor may be altered by alternative splicing.

Activation of benzoporphyrin derivative in the circulation of mice without skin photosensitivity.

In vitro experiments with benzoporphyrin derivative monoacid ring A (BPD) confirmed earlier studies that it was taken up rapidly (within 30 min) to maximum concentrations by all cells tested. It was also confirmed that rapidly dividing tumor cell lines and mitogen-activated murine T lymphocytes took up significantly more (5-10-fold) BPD than did normal splenic lymphocytes. Further experiments were undertaken to determine whether BPD could be activated by whole-body irradiation with red light in the blood of animals, shortly after intravenous (i.v.) administration, in the absence of skin photosensitivity. It was found that shaved and depilated mice injected i.v. 60 min earlier with BPD at between 0.5 and 1.0 mg/kg could tolerate 160 J/cm2 of broad-band red light (560-900 nm) delivered, at a relatively low rate, over a 90 min time interval without developing skin photosensitivity or general phototoxicity. During the treatment time, plasma levels of BPD were between 0.7 and 1.0 micrograms/mL. The light treatment resulted in between 70 and 80% photoinactivation of circulating BPD. When L1210 tumor cells were preincubated with BPD and injected i.v. into mice immediately before total-body light treatment (160 J/cm2 of 590-900 nm light delivered over 90 min), significant reductions in circulating clonogenic tumor cells were observed in blood samples taken immediately following treatment. This indicated that sufficient light was being delivered to BPD in the blood flowing in the peripheral vasculature to effect cytotoxicity to cells containing the photosensitizer without causing either vascular or skin photosensitivity.(ABSTRACT TRUNCATED AT 250 WORDS)

A survey examining the attitudes of general dental practitioners toward change in undergraduate dental education.

AIM: To determine the attitudes of general dental practitioners toward aspects of change in undergraduate dental education. DESIGN: Descriptive postal survey using a cross-sectional random sample of general dental practitioners administered in 1997. SUBJECTS: 689 general dental practitioners practising in five regions of England with close proximity to a dental school selected by a one in two stratified random sample. RESULTS: Response rate: 70%. The questionnaire was both valid and reliable with an internal consistency reliability coefficient of 0.84. Responses identified strong support for preparing dental students for the wider role of the dentist and an emphasis toward self-directed learning. Other themes emerging from the investigation included support for learning to work as part of a dental team and for students to have experience of general dental practice early on in the undergraduate course. CONCLUSIONS: These responses have implications for curriculum design, syllabus, teaching methods, resources and staff development for dental schools in the UK.