Are medical student results affected by allocation to different sites in a dispersed rural medical school?

INTRODUCTION

As medical education becomes more decentralised, and greater use is made of rural clinical schools and other dispersed sites, attention is being paid to the quality of the learning experiences across these sites. This article explores this issue by analysing the performance data of 4 cohorts of students in a dispersed clinical school model across 4 sites. The study is set in a newly established medical school in a regional area with a model of dispersed education, using data from the second to fifth cohorts to graduate from this school.

METHODS

Summative assessment results of 4 graduating cohorts were examined over the final 2 years of the course. Two analyses were conducted: an analysis of variance of mean scores in both years across the 4 sites; and an analysis of the effect of moving to different clinical schools on the students' rank order of performance by use of the Kruskal-Wallis test.

RESULTS

Analysis revealed no significant difference in the mean scores of the students studying at each site, and no significant differences overall in the median ranking across the years. Some small changes in the relative ranking of students were noticed, and workplace-based assessment scores in the final year were higher than the examination-based scores in the previous year.

CONCLUSIONS

The choice of clinical school site for the final 2 years of an undergraduate rural medical school appears to have no effect on mean assessment scores and only a minor effect on the rank order of student scores. Workplace-based assessment produces higher scores but also has little effect on student rank order. Further studies are necessary to replicate these findings in other settings and demonstrate that student learning experiences in rural sites, while popular with students, translate into required learning outcomes, as measured by summative assessments.

Effects of imposed postfeedback delays in programmed instruction

Imposed postfeedback delays promote discrimination training; the present experiments determined whether they also improve performance in programmed instruction. In two experiments, college students completed 45 sets of Holland and Skinner's (1961) programmed text on behavior analysis in a computerized format in a three-component multiple schedule. In Experiment 1, the conditions were (a) no delay between questions, (b) a 10-s delay after each question (noncontingent delay), and (c) a 10-s delay after each question answered incorrectly (contingent delay). Noncontingent delay produced better performance than no delay and contingent delay. To determine whether performance increased in the noncontingent delay condition because subjects studied the material during delay periods, Experiment 2 tested three conditions: (a) no delay between questions, (b) a 10-s delay after each question (noncontingent delay), and (c) a 10-s delay after each question with the screen blank during the delay period. Noncontingent delay produced better performance than no delay, but there was no difference in performance between no delay and noncontingent delay with blank screen. Hence, noncontingent delay improved performance because students used delay periods to study. Furthermore, subjects preferred noncontingent delay to the other conditions, and session time increased only slightly.

An evidence-based approach to the management of the adult with nasal obstruction

BACKGROUND

Nasal obstruction is a common presenting symptom to the otolaryngology clinic. A variety of structural and mucosal abnormalities can interrupt the subjective sensation of nasal airflow.

METHODS

This review was based on a literature search last performed on 1 October 2008. Current texts and the MEDLINE, EMBASE and COCHRANE databases were searched using the subject heading nasal obstruction in combination with classification, diagnosis, therapy, drug therapy and surgery. Results were limited to include clinical trials, randomised controlled trials, meta-analyses, systematic reviews and review articles. Relevant references from selected articles were also reviewed.

CONCLUSION

We present an evidence-based approach to history-taking and clinical examination of an adult patient with nasal obstruction and provide an overview of management of the most common causative conditions.

Is nasal packing really required after septoplasty?

OBJECTIVE

Septoplasty is one of the most common operations performed by otorhinolaryngologists. Nasal packing is not an innocuous procedure. The most common problem encountered by the patients after septoplasty is the pain and discomfort during removal of the nasal packs. The objective of this study was to evaluate the results of septoplasty without postoperative nasal packing.

METHODS

Septoplasty was performed by standard technique. No nasal packing was used in these cases.

RESULTS

Seventy-eight patients were included in the study. The majority of the patients (64.1%; 50/78) on a morning list were operated. Sixty-two patients were discharged home the same day, the remaining others were discharged the next day. Our postoperative haemorrhage rate was 7.7% (6/78) and only 3.8% (3/78) patients required nasal packing. Majority (84.6%) of the patients were satisfied with the operation at the postoperative follow up 3 months later.

CONCLUSIONS

Septoplasty can be safely performed without postoperative nasal packing. Only 3.8% patients required nasal packing in this study.

How informed is consent in a modern ENT department

The Department of Health issued a model consent form for use throughout the NHS from the 1st April 2002. Details of benefits and serious or frequent risks should be included on the form. We undertook a study to identify what proportion of complications from otolaryngology procedures were being recorded. Local morbidity and mortality records and case notes were examined from March to November 2004. Complications were identified and recorded. The consent forms for these operations were examined to identify if these complications had been recorded on the form prior to surgery. Complications were classified as "serious", causing significant morbidity or increasing length of hospital stay or "frequent", occurring in 1% or more of cases. A total of 2,978 operations were performed between March and November 2004. Seventy complications were identified in 60 patients (2% of operated patients). Twenty-three complications were not recorded on the consent forms in 20 (33%) patients. A total of 67% of all the complications were documented on the form as potential problems resulting from planned operations. Seven (74%) of complications that occurred but were not recorded on the consent forms were judged as "serious" or "frequent". A significant proportion of serious or frequent complications are not being documented on the national consent forms before otolaryngological procedures and may not have been discussed. This may reflect a lack of openness during the consent process. In the current medical climate, this has serious ethical and medico-legal ramifications. It may also reflect a problem with the form and a need for a re-think of its design.

Direct mechanical measurement of geodesic structures in rat mesenchymal stem cells

During numerous biological processes, cell adhesion, cell migration and cell spreading are vital. These basic biological functions are regulated by the interaction of cells with their extracellular environment. To examine the morphology and mechanical changes occurring in mesenchymal stem cells cultured on a mechanically rigid substrate, atomic force microscopy and fluorescence microscopy were employed. Investigations of the cells revealed both linear and geodesic F-actin configurations. No particular cell characteristics or intra-cellular location were implicated in the appearance of the geodesic structures. However, the length of time the cells were cultured on the substrate correlated with the percentage appearance of the geodesic structures. Calculating energy dissipation from cell images acquired by dynamic mode atomic force microscopy, it was observed that the vertices of the geodesic structures had significantly higher energy dissipation compared to the linear F-actin and the glass. This supports work by Lazarides [J. Cell Biol. 68, 202-219 (1976)], who postulated that the vertices of these geodesic structures should have a greater flexibility. Our results also support predictions based on the microfilament tensegrity model. By understanding the basic principles of cell ultrastructure and cell mechanics in relation to different extracellular environments, a better understanding of physiological and pathological process will be elicited.

Identification of genetic alterations in pancreatic cancer by the combined use of tissue microdissection and array-based comparative genomic hybridisation

Pancreatic ductal adenocarcinoma (PDAC) is characterised pathologically by a marked desmoplastic stromal reaction that significantly reduces the sensitivity and specificity of cytogenetic analysis. To identify genetic alterations that reflect the characteristics of the tumour in vivo, we screened a total of 23 microdissected PDAC tissue samples using array-based comparative genomic hybridisation (array CGH) with 1 Mb resolution. Highly stringent statistical analysis enabled us to define the regions of nonrandom genomic changes. We detected a total of 41 contiguous regions (>3.0 Mb) of copy number changes, such as a genetic gain at 7p22.2–p15.1 (26.0 Mb) and losses at 17p13.3–p11.2 (13.6 Mb), 18q21.2–q22.1 (12.0 Mb), 18q22.3–q23 (7.1 Mb) and 18q12.3–q21.2 (6.9 Mb). To validate our array CGH results, fluorescence in situ hybridisation was performed using four probes from those regions, showing that these genetic alterations were observed in 37–68% of a separate sample set of 19 PDAC cases. In particular, deletion of the SEC11L3 gene (18q21.32) was detected at a very high frequency (13 out of 19 cases; 68%) and in situ RNA hybridisation for this gene demonstrated a significant correlation between deletion and expression levels. It was further confirmed by reverse transcription–PCR that SEC11L3 mRNA was downregulated in 16 out of 16 PDAC tissues (100%). In conclusion, the combination of tissue microdissection and array CGH provided a valid data set that represents in vivo genetic changes in PDAC. Our results raise the possibility that the SEC11L3 gene may play a role as a tumour suppressor in this disease.

Postnatal exposure to octylphenol decreases semen quality in the adult ram

The aim of this experiment was to determine if maternal exposure to octylphenol pre- and/or postnatally influenced FSH concentrations and semen quantity and quality in postpubertal rams. Rams were born to ewes that received twice-weekly s.c. injections of octylphenol equivalent to 1000microg/kg/day for one of the following periods: (1) day 70 of gestation (D70) to weaning (at 20 weeks postnatally; n=4); (2) D70 to birth (n=6); (3) birth to weaning (n=7), controls received corn oil from D70 to weaning (n=5). Rams were blood-sampled weekly and semen characteristics were evaluated at 1 year of age. Maternal exposure to octylphenol, pre- and/or postnatally did not affect FSH concentrations, semen volume, concentration, percentage live, motility or IVM/IVF characteristics. However, exposure to octylphenol from birth to weaning increased the number of morphologically abnormal sperm cells in the ejaculates of these rams.

A positive role for PEA3 in HER2-mediated breast tumour progression

Overexpression of HER2 is associated with an adverse prognosis in breast cancer. Despite this, the mechanism of its transcriptional regulation remains poorly understood. PEA3, a MAP kinase (MAPK)-activated member of the Ets transcription factor family has been implicated in the transcriptional regulation of HER2. The direction of its modulation remains controversial. We assessed relative levels of PEA3 expression and DNA binding in primary breast cultures derived from patient tumours (n=18) in the presence of an activated MAPK pathway using Western blotting and shift analysis. Expression of PEA3 in breast tumours from patients of known HER2 status (n=107) was examined by immunohistochemistry. In primary breast cancer cell cultures, growth factors induced interaction between PEA3 and its DNA response element. Upregulation of PEA3 expression in the presence of growth factors associated with HER2 positivity and axillary lymph node metastasis (P=0.034 and 0.049, respectively). PEA3 expression in breast cancer tissue associated with reduced disease-free survival (P<0.001), Grade III tumours (P<0.0001) and axillary lymph node metastasis (P=0.026). Co-expression of PEA3 and HER2 significantly associated with rate of recurrence compared to patients who expressed HER2 alone (P=0.0039). These data support a positive role for PEA3 in HER2-mediated oncogenesis in breast cancer.

Disease severity and genetic pathways in attenuated familial adenomatous polyposis vary greatly but depend on the site of the germline mutation

BACKGROUND

Attenuated familial adenomatous polyposis (AFAP) is associated with germline mutations in the 5', 3', and exon 9 of the adenomatous polyposis coli (APC) gene. These mutations probably encode a limited amount of functional APC protein.

METHODS AND RESULTS

We found that colonic polyp number varied greatly among AFAP patients but members of the same family tended to have more similar disease severity. 5' Mutants generally had more polyps than other patients. We analysed somatic APC mutations/loss of heterozygosity (LOH) in 235 tumours from 35 patients (16 families) with a variety of AFAP associated germline mutations. In common with two previous studies of individual kindreds, we found biallelic changes ("third hits") in some polyps. We found that the "third hit" probably initiated tumorigenesis. Somatic mutation spectra were similar in 5' and 3' mutant patients, often resembling classical FAP. In exon 9 mutants, in contrast, "third hits" were more common. Most "third hits" left three 20 amino acid repeats (20AARs) on the germline mutant APC allele, with LOH (or proximal somatic mutation) of the wild-type allele; but some polyps had loss of the germline mutant with mutation leaving one 20AAR on the wild-type allele.

CONCLUSIONS

We propose that mutations, such as nt4661insA, that leave three 20AARs are preferentially selected in cis with some AFAP mutations because the residual protein function is near optimal for tumorigenesis. Not all AFAP polyps appear to need "three hits" however. AFAP is phenotypically and genetically heterogeneous. In addition to effects of different germline mutations, modifier genes may be acting on the AFAP phenotype, perhaps influencing the quantity of functional protein produced by the germline mutant allele.

Otitis media and a neck lump--current diagnostic challenges for Paragonimus-like trematode infections

A 29 year-old Nigerian studying in the UK presented with a neck lump and otitis media. Paragonimus-like trematode eggs were found in the neck lump aspirate. Morphologically these eggs resembled Paragonimus uterobilateralis or Achillurbainia congolensis. We favoured the diagnosis of achillurbainiasis over extrapulmonary paragonimiasis on the basis of clinical features and because we could not amplify DNA sequences using PCR primers specific for Paragonimus species. We discuss current diagnostic challenges for this rare parasitic infection.

Transforming growth factor-beta (TGF-β) in acute injuries of the spinal cord

Injuries to the spinal cord may be associated with increased healing of fractures. This can be of benefit, but excessive bone growth can also cause considerable adverse effects.

We evaluated two groups of patients with fractures of the spinal column, those with neurological compromise (n = 10) and those without (n = 15), and also a control group with an isolated fracture of a long bone (n = 12). The level of transforming growth factor-beta (TGF-β), was measured at five time points after injury (days 1, 5, 10, 42 and 84).

The peak level of 142.79 ng/ml was found at day 84 in the neurology group (p < 0.001 vs other time points). The other groups peaked at day 42 and had a decrease at day 84 after injury (p ≤ 0.001).

Our findings suggest that TGF-β may have a role in the increased bone turnover and attendant complications seen in patients with acute injuries to the spinal cord.

How I do it? Excision of neck lumps under local anaesthesia

Excisions of neck lesions under local anaesthesia are made technically more difficult by the injection of anaesthetic agent, causing the lesion to become less palpable. Pen marking the lesion can circumvent the problem; however, this marking often disappears after skin preparation. We describe a technique which abolishes this problem.

Inverse relationship between ER-beta and SRC-1 predicts outcome in endocrine-resistant breast cancer

The oestrogen receptor (ER) interacts with coactivator proteins to modulate genes central to breast tumour progression. Oestrogen receptor is encoded for by two genes, ER-α and ER-β. Although ER-α has been well characterized, the role of ER-β as a prognostic indicator remains unresolved. To determine isoform-specific expression of ER and coexpression with activator proteins, we examined the expression and localisation of ER-α, ER-β and the coactivator protein steroid receptor coactivator 1 (SRC-1) by immunohistochemistry and immunofluorescence in a cohort of human breast cancer patients (n=150). Relative levels of SRC-1 in primary breast cultures derived from patient tumours in the presence of β-oestradiol and tamoxifen was assessed using Western blotting (n=14). Oestrogen receptor-β protein expression was associated with disease-free survival (DFS) and inversely associated with the expression of HER2 (P=0.0008 and P<0.0001, respectively), whereas SRC-1 was negatively associated with DFS and positively correlated with HER2 (P<0.0001 and P<0.0001, respectively). Steroid receptor coactivator 1 protein expression was regulated in response to β-oestradiol or tamoxifen in 57% of the primary tumour cell cultures. Protein expression of ER-β and SRC-1 was inversely associated (P=0.0001). The association of ER-β protein expression with increased DFS and its inverse relationship with SRC-1 suggests a role for these proteins in predicting outcome in breast cancer.

Expression of SRC-1, AIB1, and PEA3 in HER2 mediated endocrine resistant breast cancer; a predictive role for SRC-1

BACKGROUND

In human breast cancer, the growth factor receptor HER2 is associated with disease progression and resistance to endocrine treatment. Growth factor induced mitogen activated protein kinase activity can phosphorylate not only the oestrogen receptor, but also its coactivator proteins AIB1 and SRC-1.

AIM

To determine whether insensitivity to endocrine treatment in HER2 positive patients is associated with enhanced expression of coactivator proteins, expression of the HER2 transcriptional regulator, PEA3, and coregulatory proteins, AIB1 and SRC-1, was assessed in a cohort of patients with breast cancer of known HER2 status.

METHODS

PEA3, AIB1, and SRC-1 protein expression in 70 primary breast tumours of known HER2 status (HER2 positive, n = 35) and six reduction mammoplasties was assessed using immunohistochemistry. Colocalisation of PEA3 with AIB1 and SRC-1 was determined using immunofluorescence. Expression of PEA3, AIB1, and SRC-1 was correlated with clinicopathological parameters.

RESULTS

In primary breast tumours expression of PEA3, AIB1, and SRC-1 was associated with HER2 status (p = 0.0486, p = 0.0444, and p = 0.0012, respectively). In the HER2 positive population, PEA3 expression was associated with SRC-1 (p = 0.0354), and both PEA3 and SRC-1 were significantly associated with recurrence on univariate analysis (p = 0.0345; p<0.0001). On multivariate analysis, SRC-1 was significantly associated with disease recurrence in HER2 positive patients (p = 0.0066).

CONCLUSION

Patients with high expression of HER2 in combination with SRC-1 have a greater probability of recurrence on endocrine treatment compared with those who are HER2 positive but SRC-1 negative. SRC-1 may be an important predictive indicator and therapeutic target in breast cancer.

Prevalence and number of Salmonella in irish retail pork sausages

A national Salmonella control program in the pork industry was enacted in Ireland in August 2002. This study was undertaken as part of a larger project investigating the role of pork as a source of human salmonellosis in Ireland. The objective of this survey was to assess the prevalence of Salmonella in Irish pork sausage at retail level. Samples, comprising branded prepacked sausages and loose sausages from supermarket meat counters and butcher shops, were collected from selected retail sites in four cities from October to December 2001 and from June to August 2002. A three-tube most-probable-number method was used to enumerate Salmonella in a selected number of samples that were positive by enrichment. Salmonella serotypes were detected in 4.4 and 1.7% of samples at each of the respective sampling periods, a level similar to those reported in other U.S. and U.K. studies. Isolates were characterized by serotype, phage type, and antimicrobial susceptibility. Eighteen (70%) were resistant to at least one antimicrobial, and 15 (58%) were resistant to four or more antimicrobials. Most of the isolates exhibited resistance to tetracycline. Five different phage types were detected. DT104 was the predominant phage type among Salmonella Typhimurium isolates. This study revealed that multidrug-resistant salmonellae are present in a proportion of Irish sausages and that further risk analysis work is necessary in order to quantify the risk posed to public health.

Consent for tonsillectomy

Rulings in recent negligence cases reveal a shift towards what the 'reasonable patient' would expect in deciding the risks doctors must disclose to patients. This survey aimed to investigate whether the 'reasonable patient' and 'responsible body of medical opinion' agree about which risks should be discussed regarding tonsillectomy. Using questionnaires, surgeons were asked which of the 10 complications they routinely discussed and patients were asked how seriously they regarded these complications. The results were compared with the Test of Proportions. Most surgeons routinely mentioned otalgia, odynophagia, throat infection and re-operation. Most patients regarded potentially fatal bleeding, pneumonia and blood transfusion as very serious but only the minority of surgeons mentioned these (P < 0.001). When obtaining consent for tonsillectomy, surgeons do not routinely mention all the risks that the 'reasonable patient' would expect. The 'reasonable patient' would expect that re-operation, transfusion, pneumonia and fatal blood loss are discussed.

Estimation of infection prevalence from correlated binomial samples

Infection prevalence in a population often is estimated from grouped binary data expressed as proportions. The groups can be families, herds, flocks, farms, etc. The observed number of cases generally is assumed to have a Binomial distribution and the estimate of prevalence is then the sample proportion of cases. However, the individual binary observations might not be independent--leading to overdispersion. The goal of this paper was to demonstrate random-effects models for the estimation of infection prevalence from data which are correlated and in particular, to illustrate a nonparametric random-effects model for this purpose. The nonparametric approach is a relatively recent addition to the random-effects class of models and does not appear to have been discussed previously in the veterinary epidemiology literature. The assumptions for a logistic-regression model with a nonparametric random effect were outlined. In a demonstration of the method on data relating to Salmonella infection in Irish pig herds, the nonparametric method resulted in the classification of herds into a small number of distinct prevalence groups (i.e. low, medium and high prevalence) and also estimated the relative frequency of each prevalence category in the population. We compared the estimates from a logistic model with a nonparametric distribution for the random effects with four alternative models: a logistic-regression model with no random effects, a marginal model using a generalised estimating equation (GEE) and two methods of fitting a Normally distributed random effect (the GLIMMIX macro and the NLMIXED procedure both in SAS). Parameter estimates from random-effects models are not readily interpretable in terms of prevalences. Therefore, we outlined two methods for calculating population-averaged estimates of prevalence from random-effects models: one using numerical integration and the other using Monte Carlo simulation.