Determinants of physical health in frail older people: the importance of self-efficacy

Objective: There is continued uncertainty regarding the strength of association between performance-based and self-report measures of physical functioning, and of their relationship to self-efficacy and health-related quality of life (HRQoL). This study assessed the inter-relationships between such measures, and the predictors of ‘physical’ aspects of HRQoL in frail older patients.

Design: We used statistical models to determine the predictors of ‘physical’ HRQoL, according to the physical component summary score and the physical functioning domain of the 36-item short form (SF-36) questionnaire.

Setting: Patients were recruited from hospitals in Australia and New Zealand and followed up in their homes.

Subjects: Two hundred and forty-three frail older patients.

Main measures: Physical functioning was assessed using three performance-based measures (Timed Up and Go Test, gait speed and the Berg Balance Scale) and five self-report measures, including the modified falls self-efficacy scale, at three and six months after registration.

Results: A moderate association (r=0.48=0.55) was found between each of the performance-based and self-report measures, including the SF-36 physical component summary score. Multiple linear regression analyses showed that the performance-based measures and falls self-efficacy predicted 33% of the SF-36 physical component summary score. Falls self-efficacy was the single highest predictor of both the SF-36 physical component summary score and SF-36 physical functioning domain. A curvilinear relationship was found between the SF-36 physical functioning domain and two variables: falls self-efficacy and the Berg Balance Scale.

Conclusions: Although performance-based and self-report measures provide complementary but distinct measures of physical function, psychosocial factors such as self-efficacy have a strong influence on the HRQoL of frail older people.

Overt Visual Attention in Parkinson's Disease

The ability of Parkinsonian (PD) patients to control overt visual attention was investigated, by measuring reaction time to a visual stimulus presented at different distances (1.5 deg, 6 deg, and 12 deg) and directions (left or right) from a central fixation point. Prior to the onset of the target stimulus (a square), a cue stimulus appeared just above the fixation point. With equal probability, the arrow pointed to the left, or to the right, or was ambiguous (with two heads). On 20% of their presentations, the left and right arrows pointed in the direction opposite to where the target was to appear. Subjects were informed that 20% of cues would be misleading, and correcting lenses were used to optimise their visual acuity. In previous work with a similar paradigm, only one target eccentricity was used, and subjects were not refracted, leaving open the possibility that PD subjects had more difficulty in seeing the cues and targets.

The eight PD subjects had longer reaction times than age-matched normal controls (and were relatively slower for the more eccentric targets), but made fewer errors in all conditions. In particular, they were more accurate than the controls on the presentations when the cue was misleading or ambiguous, suggesting that the PD group were ignoring the cue. It seems unlikely that the subjects discriminate the direction of the cues, given the use of optical correction, and they reported seeing the cues. Our data are consistent with those of other workers who have described a similar ‘disengagement of attention’ in PD (Clark et al, 1989 Neuropsychologia27 131 – 140) and attributed it to decreased catecholaminergic activity following destruction of midbrain structures (Wright et al, 1990 Neuropsychologia28 151 – 159).

Hospital Re-Admissions: An Empirical Analysis of Quality Management in Taiwan

This retrospective study uses discharge-level data to analyse and assess the situation of re-admissions within 15 days of discharge, for quality evaluation. The re-admission rate of the study period was 3.22%. Among those re-admission cases, 45.7% patients were re-admitted within five days of discharge, and 33.5% cases returned to hospital six to 10 days after discharge. The average length of stays of re-admissions (9.86 days for previous stay and 8.10 days for re-admitted stay) were both longer than the hospital's overall average (7.63 days) at the same period. Paediatric patients comprised the greatest number of re-admissions. Re-admissions were more likely to have higher percentage of emergency admission. Significant relationships were found between factors for re-admissions and patient characteristics (e.g. age and insurance status), admitted department, and diagnosis. Further investigation and strategies, combined with the application of severity adjustment technique to better monitor and avoid unnecessary re-admissions, need to be developed.

Body Mass Index Is Positively Associated with Endometrial Cancer in Chinese Women, Especially Prior to Menopause

Objective: Obesity is a well-known risk factor for developing endometrial cancer. However, the incidence and survival rate of endometrial cancer are associated with ethnicity and geographical area. In addition, whether menopausal status is associated with developing endometrial cancer in obese women and whether obesity is associated with subtypes of endometrial cancer have not been fully investigated. Here, we investigated the effect of BMI on developing endometrial cancer in Chinese women taking into account menopausal status and cancer subtypes.

Methods: Data on 1,127 women with endometrial cancer including body mass index (BMI), age at diagnosis, parity, menopausal status and cancer subtype were collected from the largest obstetrics & gynaecology hospital in China and analysed.

Results: After adjusting for age and parity, the odds for developing endometrial cancer in overweight or obese perimenopausal women was significantly higher than that in women with normal weight (OR=2.6 with 95%CI:1.9-3.5, and OR=3.5 with 95%CI: 2.2-5.4, respectively). The odds of developing endometrial cancer in overweight postmenopausal women were significantly higher than that in women who were normal weight (OR=2.4 with 95%CI: 1.8-3.1), however this was not the case for obese postmenopausal women. We further found that BMI, menopausal status, age and parity were not associated with subtypes of endometrial cancer.

Conclusion: Our data demonstrate that obesity is positively associated with the incidence of developing endometrial cancer in Chinese women, with more significant effects in perimenopausal women.

The Reduction in Circulating Melatonin Level May Contribute to the Pathogenesis of Ovarian Cancer: A Retrospective Study

Ovarian cancer is the third most common gynaecological malignancy. Changes in circadian rhythms such as bright light exposure may affect female reproductive physiology. Night shift work is associated with higher risks of developing gynaecological cancers. In addition, the season of birth is also suggested as an important environmental risk factor for developing gynaecological cancers. Melatonin may play an important role in this association as a marker of circadian rhythms. Serum from 96 women with ovarian cancer and 40 healthy women were collected and the level of melatonin was measured. In addition 277 women with ovarian cancer and 1076 controls were retrospectively collected for season of birth analysis over seven years. The serum levels of melatonin were significantly lower in women with ovarian cancer compared with healthy women (p<0.05). However there was no difference in melatonin levels in perimenopausal and postmenopausal patients. In addition, there is no statistically significant difference in seasonal distribution of birth between ovarian cancer patients and the control group. The melatonin levels in ovarian cancer patients and controls were not associated with the season of birth. Our results demonstrate the lower serum levels of melatonin in ovarian cancer patients which may contribute to the pathogenesis of ovarian cancer. The incidence of ovarian cancer was not associated with the season of birth. The serum levels of melatonin do not appear to be associated with season of birth in ovarian cancer patients.

Abstract P1-02-01: Genomic analysis of single cells isolated by a pulse laser retrieval system

Background: Isolating tumor cells of interest and harvesting histologically pure samples is important for genomic studies. Laser capture microdissection (LCM) is an established method to obtain such purified cell populations for various applications including DNA, gene expression, and single cell analyses. However, LCM possesses problems such as limited optical resolution, cell fragmentation from dissection, and adherence of adjacent tissue to the cells which interrupts with single cell isolation from tissue sections. To overcome these obstacles, we developed a high-throughput pulse laser retrieval system which uses a wavelength that minimizes damage to the cellular content and is processed with a sacrificial layer that provides applicable optical resolution. The aim of this study was to evaluate the performance of the pulse laser retrieval system to provide appropriate samples for genomic analysis using breast cancer tissue.

Methods: An indium tin oxide (ITO) coated glass slide was prepared using fresh frozen breast cancer tissue sections of 4㎛ thickness and stained by hematoxylin and eosin. The slide was mounted on the cell isolation machine and imaging was performed with a charge-coupled device camera using a 20× lens. Following identification of the target cells by a pathologist, nano-second pulsed laser (wavelength= 1064nm) was irradiated on the target. Isolated cells were collected in a polymerase chain reaction tube and whole genome amplification (WGA) was carried out using Illustra GenomiPhi V2 DNA Amplification Kit (GE Healthcare Life Sciences, Pittsburgh, PA, USA). Amplified genomic DNA was fragmented and Illumina sequencing libraries were constructed. Sequencing was carried out to generate data with 0.1∼0.2× depth throughout the whole genome for each sample. Copy number variation (CNV) was analyzed by the Variable binning algorithm.

Results: Whole genome amplification was performed using bulk tissue and 10 captured single cells from the same specimen. No difference in amplification coverage was observed between the two samples. A CNV analysis of captured single cells revealed similar CNV profiles with those in a matched bulk tumor. Whole exome sequencing (WES) of captured single cells yielded a variant frequency of 15% at a read depth of 15× and 50M base coverage, compared to 0% at 100× and 50M for WES using bulk tumor and 0.5% at 1200× and 100K for targeted sequencing using bulk tumor. Laser capture was performed for DCIS and stromal cells from the same slide. CNV analysis of the two samples showed minimal CNV in normal stromal cells in contrast to DCIS where multiple CNVs were observed.

Conclusions: Newly developed pulse laser retrieval system is suitable for capturing single cells for genomic analysis of breast cancer. WGA, WES, and CNV analysis was successfully carried out using the captured single cells and showed no difference in profile compared to those performed with bulk tissue. This method may have the potential to replace LCM for certain applications such as single cell analyses.

Citation Format: Lee H-B, Kim S, Lee K-M, Jung Y, Lee AC, Kim J, Bae S, Ryu HS, Yoo T-K, Moon H-G, Noh D-Y, Kwon S, Han W. Genomic analysis of single cells isolated by a pulse laser retrieval system. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-02-01.

Associations between body mass index and maternal weight gain on the delivery of LGA infants in Chinese women with gestational diabetes mellitus

BACKGROUND

Women with gestational diabetes mellitus (GDM) are at increased risk for maternal and fetal complications including delivery of large for gestational age (LGA) infants. Maternal body mass index (BMI) and excessive weight gain during pregnancy are associated with delivery of LGA infants. However, whether maternal BMI and weight gain are associated with LGA infants in women with GDM is unclear.

BASIC PROCEDURES

Data on 1049 pregnant women who developed GDM were collected from a university teaching hospital in China and retrospectively analyzed. Data included maternal BMI, weight gain, incidence of LGA and gestational week at diagnosis.

MAIN FINDINGS

The incidence of LGA infants was significantly associated with maternal BMI (p=0.0002) in women with GDM. The odds of delivery of LGA for obese or overweight pregnant women are 3.8 or 2 times more than normal weight pregnant women. The incidence of LGA infants was also significantly associated with maternal weight gain in women with GDM. The odds ratio of delivery of LGA for pregnant women with excessive weight gain was 3.3 times more than pregnant women with normal weight gain. The effect of weight gain was not significantly different between different maternal BMI.

PRINCIPAL CONCLUSION

The incidence of delivery of LGA infants in Chinese women with GDM who were overweight or obese is higher than Caucasians, Hispanic, and Asian-Americans. The effects of maternal BMI and weight gain on the delivery of LGA infants by women with GDM are additive.

The projected burden of hearing loss in New Zealand (2011-2061) and the implications for the hearing health workforce

BACKGROUND

There is considerable evidence that New Zealand's population is ageing. For example, the median age increased from 29 years in 1951 to 37 years in 2011-12, and will likely increase to 44 years by 2061. While the implications of an ageing population have been studied, to date there is no study investigating the impacts that population ageing will have on hearing health in New Zealand.

AIM

To explore the changing population structure and estimate the burden of hearing loss in New Zealand between 2011 and 2061.

METHODS

Using three alternative population projections from Statistics New Zealand, we quantify the likely distribution of the population between 2011 and 2061 by age and sex. Published estimates of hearing loss stratified by age and severity of hearing loss were then applied to the population projections to highlight the potential impact that population ageing will have on hearing loss in New Zealand in the next 50 years.

RESULTS

We estimated that there were 330,269 people aged ≥14 years with hearing loss and this would increase to 449,453 in 2061. Overall, males have a higher prevalence of hearing loss than females, and while the prevalence of hearing loss among those aged 14-49 years is expected to decrease, the prevalence among the population aged ≥70 years is expected to double between 2011 and 2061.

CONCLUSION

Age, sex and geographical variations in hearing loss are expected in the next 50 years. Further research into ethnic and variations in hearing loss will be instrumental in targeting the future hearing health workforce required to accommodate these increases.

Cochlear ablation effects on amino acid levels in the chinchilla cochlear nucleus

Inner ear damage can lead to hearing disorders, including tinnitus, hyperacusis, and hearing loss. We measured the effects of severe inner ear damage, produced by cochlear ablation, on the levels and distributions of amino acids in the first brain center of the auditory system, the cochlear nucleus. Measurements were also made for its projection pathways and the superior olivary nuclei. Cochlear ablation produces complete degeneration of the auditory nerve, which provides a baseline for interpreting the effects of partial damage to the inner ear, such as that from ototoxic drugs or intense sound. Amino acids play a critical role in neural function, including neurotransmission, neuromodulation, cellular metabolism, and protein construction. They include major neurotransmitters of the brain - glutamate, glycine, and γ-aminobutyrate (GABA) - as well as others closely related to their metabolism and/or functions - aspartate, glutamine, and taurine. Since the effects of inner ear damage develop over time, we measured the changes in amino acid levels at various survival times after cochlear ablation. Glutamate and aspartate levels decreased by 2weeks in the ipsilateral ventral cochlear nucleus and deep layer of the dorsal cochlear nucleus, with the largest decreases in the posteroventral cochlear nucleus (PVCN): 66% for glutamate and 63% for aspartate. Aspartate levels also decreased in the lateral part of the ipsilateral trapezoid body, by as much as 50%, suggesting a transneuronal effect. GABA and glycine levels showed some bilateral decreases, especially in the PVCN. These results may represent the state of amino acid metabolism in the cochlear nucleus of humans after removal of eighth nerve tumors, which may adversely result in destruction of the auditory nerve. Measurement of chemical changes following inner ear damage may increase understanding of the pathogenesis of hearing impairments and enable improvements in their diagnosis and treatment.

Movers and stayers: The geography of residential mobility and CVD hospitalisations in Auckland, New Zealand

The association between area-level disadvantage and health and social outcomes is unequivocal. However, less is known about the health impact of residential mobility, particularly at intra-urban scales. We used an encrypted National Health Index (eNHI) number to link individual-level data recorded in routine national health databases to construct a cohort of 641,532 participants aged 30+ years to investigate the association between moving and CVD hospitalisations in Auckland, New Zealand. Residential mobility was measured for participants according to changes in the census Meshblock of usual residence, obtained from the Primary Health Organisation (PHO) database for every calendar quarter between 1/1/2006 and 31/12/2012. The NZDep2006 area deprivation score at the start and end of a participant's inclusion in the study was used to measure deprivation mobility. We investigated the relative risk of movers being hospitalised for CVD relative to stayers using multi-variable binomial regression models, controlling for age, gender, deprivation and ethnicity. Considered together, movers were 1.22 (1.19-1.26) times more likely than stayers to be hospitalised for CVD. Using the 5×5 deprivation origin-destination matrix to model a patient's risk of CVD based on upward, downward or sideways deprivation mobility, movers within the least deprived (NZDep2006 Quintile 1) areas were 10% less likely than stayers to be hospitalised for CVD, while movers within the most deprived (NZDep2006 Q5) areas were 45% more likely than stayers to have had their first CVD hospitalisation in 2006-2012 (RR: 1.45 [1.35-1.55]). Participants who moved upward also had higher relative risks of having a CVD event, although their risk was less than those observed for participants experiencing downward deprivation mobility. This research suggests that residential mobility is an important determinant of CVD in Auckland. Further investigation is required to determine the impact moving has on the risk of CVD by ethnicity.

MRI osteitis predicts cartilage damage at the wrist in RA: a three-year prospective 3T MRI study examining cartilage damage

Introduction

Cartilage damage impacts on patient disability in rheumatoid arthritis (RA). The aims of this magnetic resonance imaging (MRI) study were to investigate cartilage damage over three years and determine predictive factors.

Methods

A total of 38 RA patients and 22 controls were enrolled at t = 0 (2009). After 3 years, clinical and MRI data were available in 28 patients and 15 controls. 3T MRI scans were scored for cartilage damage, bone erosion, synovitis and osteitis. A model was developed to predict cartilage damage from baseline parameters.

Results

Inter-reader reliability for the Auckland MRI cartilage score (AMRICS) was high for status scores; intraclass correlation coefficient (ICC), 0.90 (0.81 to 0.95) and moderate for change scores (ICC 0.58 (0.24 to 0.77)). AMRICS scores correlated with the Outcome MEasures in Rheumatoid Arthritis Clinical Trials (OMERACT) MRI joint space narrowing (jsn) and X-Ray (XR) jsn scores (r =0.96, P < 0.0001 and 0.80, P < 0.0001, respectively). AMRICS change scores were greater for RA patients than controls (P = 0.06 and P = 0.04 for the two readers). Using linear regression, baseline MRI cartilage, synovitis and osteitis scores predicted the three-year AMRICS (R² = 0.67, 0.37 and 0.39, respectively). A multiple linear regression model predicted the three-year AMRICS (R² = 0.78). Baseline radial osteitis predicted increased cartilage scores at the radiolunate and radioscaphoid joints, P = 0.0001 and 0.0012, respectively and synovitis at radioulnar, radiocarpal and intercarpal-carpometacarpal joints also influenced three-year cartilage scores (P-values of 0.001, 0.04 and 0.01, respectively).

Conclusions

MRI cartilage damage progression is preceded by osteitis and synovitis but is most influenced by pre-existing cartilage damage suggesting primacy of the cartilage damage pathway in certain patients.

P3-12-04: Involved Anterior Margins after Breast Conserving Surgery: Is Re-Excision Required?

Background: Complete tumour excision in breast conserving surgery (BCS) is critical for successful treatment; involved circumferential resection margins are associated with increased disease recurrence. However, the importance of an involved anterior margin is less clear. The purpose of this study was to audit an aggressive approach to involved anterior margins and hence assess whether anterior margin re-excision yields clinical benefit.

Material and Methods: A retrospective case note and pathology review was performed for all patients who underwent BCS between 2006 and 2010 through a single cancer centre. An involved margin was defined as &lt;1mm clearance of invasive or in situ breast cancer. Results: 1667 patients underwent BCS for invasive and/or in-situ disease, of whom 114 (6.8%) underwent re-excision, most commonly for mixed invasive and in-situ pathology. The annual re-excision rate rose significantly (p&lt;0.001), with no change in whole tumour diameter, specimen weight or specimen volume. A total of 170 involved margins were identified: most commonly the anterior margin (59 margins, 30.6%) followed by the posterior (39 22.9%) or inferior (31, 18.3%) margin. Patients with anterior margin involvement were more likely to have grade 3 invasive disease (p=0.0323) but less likely to have residual disease found at re-excision (2/49 vs. 32/101 margins, p=0.0033); there were no differences when in-situ characteristics were compared.

Conclusions: Re-excision of involved anterior margins rarely excises residual disease and may be unnecessary. Multidisciplinary teams should consider whether further therapy for an involved anterior margin is required on a patient by patient basis.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-12-04.

Attributes of response in depressed patients switched to treatment with duloxetine

BACKGROUND

This study was designed to assess clinical and functional outcomes associated with switching to duloxetine treatment in patients with major depressive disorder (MDD) experiencing emotional and painful physical symptoms in their current episode.

METHODS

In this 8-week, multinational, multicentre, single-arm, open-label clinical trial, 242 MDD patients were switched to duloxetine 60 mg/day after selective serotonin reuptake inhibitor (SSRI) or serotonin and norepinephrine reuptake inhibitor (SNRI) treatment. The primary analysis compared mean change from baseline in Brief Pain Inventory-Modified Short Form (BPI-SF) interference score between initial responders [≥ 50% reduction from baseline on the 17-item Hamilton Depression Rating Scale (HAMD(17)) Maier subscale] and initial non-responders after 4 weeks. Initial responders continued with duloxetine 60 mg/day. Initial non-responders received duloxetine 120 mg/day for the remaining 4 weeks. Depression, pain, anxiety and functional outcomes were also compared after 8 weeks.

RESULTS

BPI-SF interference decreased from baseline in initial responders (n = 108) and initial non-responders (n = 85) after 4 weeks of duloxetine treatment, with greater reductions in initial responders [BPI-SF mean difference in reduction: 1.01 (95% CI 0.42-1.61); p < 0.001]. Reductions in pain interference favouring initial responders were also apparent after 8 weeks [0.68 (95% CI: 0.03-1.33); p = 0.042]. Depression, pain, anxiety and function improved over 8 weeks across patient groups.

CONCLUSIONS

Elements of core mood and pain are important residual symptoms following poor treatment response in MDD. Early improvement in these symptoms after switching to duloxetine indicated an increased chance of functional recovery.

Pharmacological effects of cannabinoids on the Caco-2 cell culture model of intestinal permeability

Activation of cannabinoid receptors decreases emesis, inflammation, gastric acid secretion, and intestinal motility. However, the effects of cannabinoids on intestinal permeability have not yet been established. The aim of the present study is to examine the effects of cannabinoids on intestinal permeability in an in vitro model. Caco-2 cells were grown until fully confluent on inserts in 12-well plates. Transepithelial electrical resistance (TEER) measurements were made as a measure of permeability. EDTA (50 μM) was applied to reversibly increase permeability (reduce TEER). The effects of cannabinoids on permeability in combination with EDTA, or alone, were assessed. Potential target sites of action were investigated using antagonists of the cannabinoid (CB)(1) receptor, CB(2) receptor, transient receptor potential vanilloid subtype 1 (TRPV1), peroxisome proliferator-activated receptor (PPAR)γ, PPARα, and a proposed cannabinoid receptor. When applied to the apical or basolateral membrane of Caco-2 cells, Δ(9)-tetrahydrocannabinol (THC) and cannabidiol (CBD) enhanced the speed of recovery of EDTA-induced increased permeability. This effect was sensitive to cannabinoid CB(1) receptor antagonism only. Apical application of endocannabinoids caused increased permeability, sensitive to cannabinoid CB(1) receptor antagonism. By contrast, when endocannabinoids were applied basolaterally, they enhanced the recovery of EDTA-induced increased permeability, and this involved additional activation of TRPV1. All cannabinoids tested increased the mRNA of the tight junction protein zona occludens-1, but only endocannabinoids also decreased the mRNA of claudin-1. These findings suggest that endocannabinoids may play a role in modulating intestinal permeability and that plant-derived cannabinoids, such as THC and CBD, may have therapeutic potential in conditions associated with abnormally permeable intestinal epithelium.

Bruises, blood coagulation tests and the battered child syndrome

Cutaneous bruises are a common symptom and a sign of injury and blood coagulation disorders in childhood. A carefully-taken history, coupled with a thorough physical examination, would lead to the diagnosis, or guide the clinician to the necessary laboratory investigations. Most children suffering from non-accidental injury can have their diagnosis established on clinical grounds alone and do not require laboratory investigation. An initial screening with full blood counts, prothrombin time and activated partial thromboplastin time will be adequate in most cases if laboratory investigation is indicated, but the clinician must be aware of the limitations of these tests. The finding of an abnormal coagulation test does not exclude child abuse as it can be a consequence of maltreatment, or the two conditions may coexist. Whenever necessary, the opinion of a haematologist should be sought in order to obtain an accurate diagnosis, which is essential for subsequent management and the prevention of further injury in the case of child abuse.

The selective use of magnetic resonance cholangiopancreatography in the imaging of the axial biliary tree in patients with acute gallstone pancreatitis

BACKGROUND

Magnetic resonance cholangiopancreatography (MRCP) is an emerging modality in the management of acute gallstone pancreatitis (AGP). The aim of this study was to assess the impact following the introduction of MRCP in the management of AGP in a tertiary referral unit.

METHODS

Patients presenting with AGP from January 2002 to December 2004 were reviewed to assess the impact of the introduction of MRCP in June 2003. The indication for MRCP was suspected common bile duct (CBD) stones in the absence of biliary sepsis. Definitive treatment for AGP was laparoscopic cholecystectomy, with endoscopic retrograde cholangiopancreatography (ERCP) and sphincterotomy reserved for patients unfit for cholecystectomy and those with biliary sepsis.

RESULTS

249 patients were identified of whom 36 (14.5%) underwent ERCP and sphincterotomy as definitive treatment. 96 patients with a non-dilated CBD and normal or resolving liver function tests proceeded to laparosocopic cholecystectomy and intraoperative cholangiogram (IOC), 8 (8.5%) of whom had CBD stones intraoperatively. Eleven patients underwent cholecystectomy during pancreatic necrosectomy. Of those undergoing preoperative diagnostic biliary tract imaging, ERCP was undertaken in 57 patients and MRCP in 49 patients. There was no significant difference in serum bilirubin levels [ERCP 43 mmol/l (18-204) vs. MRCP 39 mmol/l (24-180), p = NS] or the proportion of patients with CBD stones [ERCP 10 (17.5%) vs. MRCP 7 (14.2%), p = NS] between the two groups. Patients who underwent MRCP had a shorter median hospital stay [MRCP 5 days (range: 3-14) vs. ERCP 9 days (range: 4-20), p < 0.01] and higher rate of cholecystectomy during the index admission (MRCP 83.3% vs. ERCP 67.2%, p < 0.05). There was a high degree of correlation between preoperative MRCP results and findings of subsequent IOC or therapeutic ERCP (area under ROC curve: 0.94).

CONCLUSIONS

MRCP is an accurate modality for imaging the axial biliary tree in patients with AGP. Selective use of MRCP reduces the need for ERCP and results in shorter hospital stay. and IAP.

Prognostic factors in patients undergoing surgery for severe necrotizing pancreatitis

Pancreatic necrosectomy remains an important treatment modality for the management of infected pancreatic necrosis but is associated with significant mortality. The aim of this study was to identify factors associated with mortality following pancreatic necrosectomy. Patients who underwent pancreatic necrosectomy from January 1995 to December 2004 were reviewed. The association between admission, preoperative and postoperative variables, and mortality was assessed using logistic regression analysis. A total of 1248 patients presented with acute pancreatitis, of whom 94 (7.5%) underwent pancreatic necrosectomy (51 men, 43 women). The preoperative median Acute Physiology, Age, and Chronic Health Evaluation (APACHE II) score was 9 (range 2-19). The median cumulative organ dysfunction score was 2 (0-9) preoperatively and 4 (1-11) postoperatively. In all, 23 patients (24.5%) died. Those who died were older than the survivors; the ages (median and range) were 69 years (40-80 years) versus 52 years (19-79 years) (p < 0.05). They also had higher admission APACHE II scores (median and range): 14 (12-19) versus 9 (2-22) (p < 0.001). There were significant associations between preoperative (p < 0.01) and postoperative (p < 0.01) Marshall scores and mortality following pancreatic necrosectomy. The presence of the systemic inflammatory response syndrome (SIRS) during the first 48 hours (p < 0.01) and the time between presentation and necrosectomy (p < 0.01) were independent predictors of survival. Pancreatic necrosectomy is associated with higher mortality in patients with increased APACHE II scores, early persistent SIRS, and unresolved multiorgan dysfunction. Necrosectomy is associated with poorer outcome when performed within 2 weeks of presentation.

Identification of susceptibility and protective major histocompatibility complex haplotypes in canine diabetes mellitus

Diabetes mellitus occurs spontaneously in dogs, which is believed to have an autoimmune component and to be a model of human latent autoimmune diabetes of adults (LADA). Some dog breeds (e.g. Samoyed) are particularly predisposed, whereas others (e.g. Boxer) are highly resistant. With the completion of the Dog Genome Assembly, comparative genomic studies of complex diseases in dogs, including diabetes, could provide an important investigative approach into such disorders. Type 1 diabetes in humans is strongly associated with major histocompatibility complex (MHC) class II polymorphisms. We have investigated whether canine dog leucocyte antigen (DLA) class II haplotypes are associated with diabetes. DNA from 460 cases and 1047 controls were genotyped for DLA-DRB1, DLA-DQA1 and DLA-DQB1 using sequence-based typing. Three DLA haplotypes, DRB1*009/DQA1*001/DQB1*008, DRB1*015/DQA1*0061/DQB1*023 and DRB1*002/DQA1*009/DQB1*001, were found at significantly increased frequency in cases with diabetes compared with controls. One DLA-DQ haplotype, DQA1*004/DQB1*013, was significantly reduced in cases with diabetes. Further analysis showed that DQA1 alleles carrying arginine at codon 55 of DQA1 were increased in dogs with diabetes. To our knowledge, this is the first report of a comparative study of MHC and diabetes in a non-rodent species. Since no laboratory model of LADA exists and dogs and humans share similar environments, further research into canine diabetes is warranted.

Spectral characterization of yeast cells with an epitaxy-based UV-Vis optical sensor

The optical spectra of yeast cells in phosphate buffer saline (PBS) were analyzed with an optical UV-vis sensor based on a shallow p(+)n junction realized in a low doped n-type epitaxial silicon layer grown on a strongly doped n(+) substrate. The presence of the n/n(+) interface allows a significantly enhanced sensitivity, due to an increased collection of carriers photogenerated both by short and large wavelengths in the range 250...800 nm. In our experiments the optical absorption of yeast cells was investigated in the wavelength range 250...500 nm as a function of the cells concentration in PBS in the range of 6 x 10(6)-2 x 10(8) cells/ml. The main absorption peaks were found at 310, 350, 400 and 427 nm, respectively. A significant red shift of the wide absorption band at 427 nm has been observed when increasing cell concentration. This red shift behaviour was nonlinear, with saturation observed for yeast concentrations larger than 5 x 10(7) cells/ml. The half-peak bandwidth of this peak also showed a most significant nonlinear variation. These findings suggest that monitoring the parameters of the absorption band at 427 nm versus cells concentration could be used, e.g. using a dedicated integrated spectrometric microsystem, for fast quantitative measurements of yeast cell concentrations in various bio-samples, with possible applications in the food industry.

Intraoperative touch imprint cytology for the diagnosis of sentinel lymph node metastases in breast cancer

Background

Intraoperative detection of sentinel lymph node (SLN) metastases enables the surgeon to take an immediate decision to proceed to completion axillary lymph node dissection (ALND). The aim of this study was to determine the accuracy of touch imprint cytology (TIC) for the diagnosis of SLN metastases in sentinel nodes from women with breast cancer.

Methods

Touch imprints from 235 sentinel nodes in 133 women with breast cancer were diagnosed by cytopathology and compared with definitive histopathology results. After a feasibility study, a real-time study was performed with the surgeon proceeding to ALND based on the TIC diagnosis. The clinical opinion of the operating surgeon as to whether the SLN appeared to contain metastases was recorded, as was the time taken for the result to be available.

Results

TIC detected metastases with a sensitivity of 81·1 per cent and a specificity of 100 per cent. False-negative TIC diagnoses were associated with micrometastases and lobular carcinoma. The majority of false-negative diagnoses were due to sampling rather than interpretation errors. Clinical assessment of sentinel nodes had a sensitivity of 64·3 per cent and a specificity of 87·6 per cent.

Conclusion

TIC is feasible and enables the rapid diagnosis of SLN metastases with an acceptable accuracy for clinical use in ductal carcinoma of the breast.

Electromechanical effects on tether formation from lipid membranes: a theoretical analysis

The material properties of biomembranes can be measured by forming a tether, a thin bilayer tube that extends from the membrane surface. Recent experiments have demonstrated that the force required to maintain a tether is sensitive to the transmembrane potential. As a first approach towards understanding this phenomenon, a thermodynamic analysis of the influence of electrical fields on tether formation from an aspirated lipid vesicle is developed. The analysis considers contributions from Maxwell stresses as well as two forms of electromechanical coupling: coupling between the electric field and curvature strain (flexoelectric coupling) and between the electric field and areal strain (piezoelectric coupling). Predictions of equilibrium tether conformations are obtained numerically. For expected values of the dimensionless coupling parameters, flexoelectric coupling alters the force required to form a tether of a given length, while piezoelectric coupling and Maxwell forces do not greatly change the force versus tether length behavior. The results of this analysis indicate that tether experiments have the potential to characterize electromechanical coupling in both synthetic and cellular membranes.

Detection of allelic variants of the canine IGHA gene by fluorescence resonance energy transfer melting temperature examination

The fluorescence resonance energy transfer (FRET) dual hybridisation probe system has been used for the detection of the accumulation of target DNA during real-time PCR and for the identification of nucleotide polymorphisms through examination of melt curves. This system involves the use of two oligonucleotide probes which are located close to each other and are complementary to an internal segment of a target DNA of interest. Four allelic variants of the gene encoding the hinge region of the immunoglobulin A (IgA) heavy chain (IGHA) have been so far identified in the dog and this variability is due to a combination of single nucleotide polymorphisms and insertion/deletion of nucleic acid motifs. An individual dog may be homozygous or heterozygous for these allelic variants. The purpose of this study was to develop a FRET-based dual probe melting temperature assay to identify the alleles present within an individual dog and to use this assay to determine the frequency of the four allelic variants in different breeds within the canine population. A single pair of oligonucleotide probes were designed that were able to discriminate between the four allelic variants in both homozygous and heterozygous individuals. The genotype of 96 DNA samples obtained from various purebreeds of dogs was determined using this FRET assay. The frequency of each allele differed between the breed groups. The results of this study indicate that it is possible to distinguish relatively complex gene polymorphisms using a single set of oligonucleotide probes. Furthermore, any future comparison of IGHA genotypes between normal and diseased dog populations must take into account the breed variation in allelic frequency.