Use of chemotherapy in patients with oesophageal, stomach, colon, rectal, liver, pancreatic, lung, and ovarian cancer: an International Cancer Benchmarking Partnership (ICBP) population-based study

BACKGROUND

There are few data on international variation in chemotherapy use, despite it being a key treatment type for some patients with cancer. Here, we aimed to examine the presence and size of such variation.

METHODS

This population-based study used data from Norway, the four UK nations (England, Northern Ireland, Scotland, and Wales), eight Canadian provinces (Alberta, British Columbia, Manitoba, Newfoundland and Labrador, Nova Scotia, Ontario, Prince Edward Island, and Saskatchewan), and two Australian states (New South Wales and Victoria). Patients aged 15-99 years diagnosed with cancer in eight different sites (oesophageal, stomach, colon, rectal, liver, pancreatic, lung, or ovarian cancer), with no other primary cancer diagnosis occurring from within the 5 years before to 1 year after the index cancer diagnosis or during the study period were included in the study. We examined variation in chemotherapy use from 31 days before to 365 days after diagnosis and time to its initiation, alongside related variation in patient group differences. Information was obtained from cancer registry records linked to clinical or patient management system data or hospital administration data. Random-effects meta-analyses quantified interjurisdictional variation using 95% prediction intervals (95% PIs).

FINDINGS

Between Jan 1, 2012, and Dec 31, 2017, of 893 461 patients with a new diagnosis of one of the studied cancers, 111 569 (12·5%) did not meet the inclusion criteria, and 781 892 were included in the analysis. There was large interjurisdictional variation in chemotherapy use for all studied cancers, with wide 95% PIs: 47·5 to 81·2 (pooled estimate 66·4%) for ovarian cancer, 34·9 to 59·8 (47·2%) for oesophageal cancer, 22·3 to 62·3 (40·8%) for rectal cancer, 25·7 to 55·5 (39·6%) for stomach cancer, 17·2 to 56·3 (34·1%) for pancreatic cancer, 17·9 to 49·0 (31·4%) for lung cancer, 18·6 to 43·8 (29·7%) for colon cancer, and 3·5 to 50·7 (16·1%) for liver cancer. For patients with stage 3 colon cancer, the interjurisdictional variation was greater than that for all patients with colon cancer (95% PI 38·5 to 78·4; 60·1%). Patients aged 85-99 years had 20-times lower odds of chemotherapy use than those aged 65-74 years, with very large interjurisdictional variation in this age difference (odds ratio 0·05; 95% PI 0·01 to 0·19). There was large variation in median time to first chemotherapy (from diagnosis date) by cancer site, with substantial interjurisdictional variation, particularly for rectal cancer (95% PI -15·5 to 193·9 days; pooled estimate 89·2 days). Patients aged 85-99 years had slightly shorter median time to first chemotherapy compared with those aged 65-74 years, consistently between jurisdictions (-3·7 days, 95% PI -7·6 to 0·1).

INTERPRETATION

Large variation in use and time to chemotherapy initiation were observed between the participating jurisdictions, alongside large and variable age group differences in chemotherapy use. To guide efforts to improve patient outcomes, the underlying reasons for these patterns need to be established.

FUNDING

International Cancer Benchmarking Partnership (funded by the Canadian Partnership Against Cancer, Cancer Council Victoria, Cancer Institute New South Wales, Cancer Research UK, Danish Cancer Society, National Cancer Registry Ireland, The Cancer Society of New Zealand, National Health Service England, Norwegian Cancer Society, Public Health Agency Northern Ireland on behalf of the Northern Ireland Cancer Registry, DG Health and Social Care Scottish Government, Western Australia Department of Health, and Public Health Wales NHS Trust).

Use of radiotherapy in patients with oesophageal, stomach, colon, rectal, liver, pancreatic, lung, and ovarian cancer: an International Cancer Benchmarking Partnership (ICBP) population-based study

BACKGROUND

There is little evidence on variation in radiotherapy use in different countries, although it is a key treatment modality for some patients with cancer. Here we aimed to examine such variation.

METHODS

This population-based study used data from Norway, the four UK nations (England, Northern Ireland, Scotland, and Wales), nine Canadian provinces (Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, Prince Edward Island, and Saskatchewan), and two Australian states (New South Wales and Victoria). Patients aged 15-99 years diagnosed with cancer in eight different sites (oesophageal, stomach, colon, rectal, liver, pancreatic, lung, or ovarian cancer), with no other primary cancer diagnosis occurring within the 5 years before to 1 year after the index cancer diagnosis or during the study period were included in the study. We examined variation in radiotherapy use from 31 days before to 365 days after diagnosis and time to its initiation, alongside related variation in patient group differences. Information was obtained from cancer registry records linked to clinical or patient management system data, or hospital administration data. Random-effects meta-analyses quantified interjurisdictional variation using 95% prediction intervals (95% PIs).

FINDINGS

Between Jan 1, 2012, and Dec 31, 2017, of 902 312 patients with a new diagnosis of one of the studied cancers, 115 357 (12·8%) did not meet inclusion criteria, and 786,955 were included in the analysis. There was large interjurisdictional variation in radiotherapy use, with wide 95% PIs: 17·8 to 82·4 (pooled estimate 50·2%) for oesophageal cancer, 35·5 to 55·2 (45·2%) for rectal cancer, 28·6 to 54·0 (40·6%) for lung cancer, and 4·6 to 53·6 (19·0%) for stomach cancer. For patients with stage 2-3 rectal cancer, interjurisdictional variation was greater than that for all patients with rectal cancer (95% PI 37·0 to 84·6; pooled estimate 64·2%). Radiotherapy use was infrequent but variable in patients with pancreatic (95% PI 1·7 to 16·5%), liver (1·8 to 11·2%), colon (1·6 to 5·0%), and ovarian (0·8 to 7·6%) cancer. Patients aged 85-99 years had three-times lower odds of radiotherapy use than those aged 65-74 years, with substantial interjurisdictional variation in this age difference (odds ratio [OR] 0·38; 95% PI 0·20-0·73). Women had slightly lower odds of radiotherapy use than men (OR 0·88, 95% PI 0·77-1·01). There was large variation in median time to first radiotherapy (from diagnosis date) by cancer site, with substantial interjurisdictional variation (eg, oesophageal 95% PI 11·3 days to 112·8 days; pooled estimate 62·0 days; rectal 95% PI 34·7 days to 77·3 days; pooled estimate 56·0 days). Older patients had shorter median time to radiotherapy with appreciable interjurisdictional variation (-9·5 days in patients aged 85-99 years vs 65-74 years, 95% PI -26·4 to 7·4).

INTERPRETATION

Large interjurisdictional variation in both use and time to radiotherapy initiation were observed, alongside large and variable age differences. To guide efforts to improve patient outcomes, underlying reasons for these differences need to be established.

FUNDING

International Cancer Benchmarking Partnership (funded by the Canadian Partnership Against Cancer, Cancer Council Victoria, Cancer Institute New South Wales, Cancer Research UK, Danish Cancer Society, National Cancer Registry Ireland, The Cancer Society of New Zealand, National Health Service England, Norwegian Cancer Society, Public Health Agency Northern Ireland on behalf of the Northern Ireland Cancer Registry, DG Health and Social Care Scottish Government, Western Australia Department of Health, and Public Health Wales NHS Trust).

Detection of Oncogenic Human Papillomavirus (HPV-16 and HPV-18) from Bacterial Vaginosis Positive Patient Attending at Tertiary Care Hospital in Mymensingh

Cervical cancer is the fourth most common cancer in women in the world and is the second leading malignancy among Bangladeshi women. Persistent infection with high risk human papillomavirus (HPV) is an important cause of development of cervical intraepithelial neoplasia (CIN) followed by cancer. Bacterial vaginosis (BV), a common treatable vaginal infection which can disrupt the balanced vaginal ecosystem and its innate protective mechanisms against infection, can play an essential role in the acquisition and persistence of high risk human papillomavirus (HR-HPV) infection. This cross sectional study was conducted to detect the HR-HPV (HPV-16 and HPV-18) infection among bacterial vaginosis positive patient in the Department of Microbiology, Mymensingh Medical College (MMC), Bangladesh, from March 2018 to February 2019. A total of 300 endocervical swabs and high vaginal swabs were collected from the VIA (Visual inspection with acetic acid) outdoor clinic of Obstetrics and Gynaecology Department of Mymensingh Medical college Hospital. HPV DNA was tested among all 300 cases by nested PCR. Typing of HPV 16 and HPV 18 was done among HPV DNA positive cases with BV and intermediate flora by multiplex PCR. BV was diagnosed according to Nugent criteria by using the gram stained smear of high vaginal swab. A total of 57/300 (19.0%) samples were positive for HPV DNA by nested PCR. Of the total 300 cases 78(26.0%) had BV, 38(13.0%) had intermediate flora and 184(61.0%) had normal vaginal flora. HPV DNA was more positive in patients having intermediate flora 08/38 (21.05%) followed by the patients having normal vaginal flora 37/184 (20.11%) and BV 12/78 (15.38%). Among the 12 BV patients who were also HPV DNA positive (83.33%) were belong to high risk HPV (type 16 and 18) group and among them 08(66.67%) were HPV-16 and 02(16.67%) were HPV-18. But among 08 HPV DNA positive intermediate flora containing patients only 01(12.5%) were belong to HR-HPV (type 16 and no type 18 was detected).

Liver virome of a Little Corella (Cacatua sanguinea) reveals coinfection with a novel parvovirus and two beak and feather disease viruses

Emerging diseases are acknowledged as a growing threat to wildlife, with the continued identification of pathogenic and potentially pathogenic viruses in avian species resulting from ongoing advances in molecular diagnostic techniques. Parvoviruses under the genus Chaphamaparvovirus (subfamily Hamaparvovirinae) are highly divergent. The detection and characterisation of parvoviruses in psittacine birds is limited. This study reports a novel parvovirus, tentatively named psittaciform chaphamaparvovirus 3 (PsChV-3) under the genus Chaphamaparvovirus, identified in an Australian free-ranging little corella (Cacatua sanguinea). The PsChV-3 genome is 4277 bp in length and encompasses four predicted open-reading frames, including two major genes, a nonstructural replicase gene (NS1), and a structural capsid gene (VP1). The NS1 and VP1 genes showed the closest amino acid identities of 78.8% and 69.7%, respectively, with a recently sequenced psittaciform chaphamaparvovirus 2 from Australian Neophema species grass parrots. In addition, the presence of two complete novel beak and feather disease (BFDV) genomes, 1993 and 1868 nt in length, respectively, were detected from the same bird. Both these BFDV genomes contained two bidirectional ORFs encoding the putative Rep and Cap proteins. Phylogenetic analysis showed that the sequenced novel BFDV genomes clustered in a distinct subclade with other BFDVs isolated from Australian cockatoos. This study contributes to the characterisation chaphamaparvoviruses and BFDV in Australian parrots and supports the need for ongoing monitoring and molecular studies into the avian virome in native Australian psittacine bird species.

Risk factors and prognostic implications of diagnosis of cancer within 30 days after an emergency hospital admission (emergency presentation): an International Cancer Benchmarking Partnership (ICBP) population-based study

BACKGROUND

Greater understanding of international cancer survival differences is needed. We aimed to identify predictors and consequences of cancer diagnosis through emergency presentation in different international jurisdictions in six high-income countries.

METHODS

Using a federated analysis model, in this cross-sectional population-based study, we analysed cancer registration and linked hospital admissions data from 14 jurisdictions in six countries (Australia, Canada, Denmark, New Zealand, Norway, and the UK), including patients with primary diagnosis of invasive oesophageal, stomach, colon, rectal, liver, pancreatic, lung, or ovarian cancer during study periods from Jan 1, 2012, to Dec 31, 2017. Data were collected on cancer site, age group, sex, year of diagnosis, and stage at diagnosis. Emergency presentation was defined as diagnosis of cancer within 30 days after an emergency hospital admission. Using logistic regression, we examined variables associated with emergency presentation and associations between emergency presentation and short-term mortality. We meta-analysed estimates across jurisdictions and explored jurisdiction-level associations between cancer survival and the percentage of patients diagnosed as emergencies.

FINDINGS

In 857 068 patients across 14 jurisdictions, considering all of the eight cancer sites together, the percentage of diagnoses through emergency presentation ranged from 24·0% (9165 of 38 212 patients) to 42·5% (12 238 of 28 794 patients). There was consistently large variation in the percentage of emergency presentations by cancer site across jurisdictions. Pancreatic cancer diagnoses had the highest percentage of emergency presentations on average overall (46·1% [30 972 of 67 173 patients]), with the jurisdictional range being 34·1% (1083 of 3172 patients) to 60·4% (1317 of 2182 patients). Rectal cancer had the lowest percentage of emergency presentations on average overall (12·1% [10 051 of 83 325 patients]), with a jurisdictional range of 9·1% (403 of 4438 patients) to 19·8% (643 of 3247 patients). Across the jurisdictions, older age (ie, 75-84 years and 85 years or older, compared with younger patients) and advanced stage at diagnosis compared with non-advanced stage were consistently associated with increased emergency presentation risk, with the percentage of emergency presentations being highest in the oldest age group (85 years or older) for 110 (98%) of 112 jurisdiction-cancer site strata, and in the most advanced (distant spread) stage category for 98 (97%) of 101 jurisdiction-cancer site strata with available information. Across the jurisdictions, and despite heterogeneity in association size (I2=93%), emergency presenters consistently had substantially greater risk of 12-month mortality than non-emergency presenters (odds ratio >1·9 for 112 [100%] of 112 jurisdiction-cancer site strata, with the minimum lower bound of the related 95% CIs being 1·26). There were negative associations between jurisdiction-level percentage of emergency presentations and jurisdiction-level 1-year survival for colon, stomach, lung, liver, pancreatic, and ovarian cancer, with a 10% increase in percentage of emergency presentations in a jurisdiction being associated with a decrease in 1-year net survival of between 2·5% (95% CI 0·28-4·7) and 7·0% (1·2-13·0).

INTERPRETATION

Internationally, notable proportions of patients with cancer are diagnosed through emergency presentation. Specific types of cancer, older age, and advanced stage at diagnosis are consistently associated with an increased risk of emergency presentation, which strongly predicts worse prognosis and probably contributes to international differences in cancer survival. Monitoring emergency presentations, and identifying and acting on contributing behavioural and health-care factors, is a global priority for cancer control.

FUNDING

Canadian Partnership Against Cancer; Cancer Council Victoria; Cancer Institute New South Wales; Cancer Research UK; Danish Cancer Society; National Cancer Registry Ireland; The Cancer Society of New Zealand; National Health Service England; Norwegian Cancer Society; Public Health Agency Northern Ireland, on behalf of the Northern Ireland Cancer Registry; the Scottish Government; Western Australia Department of Health; and Wales Cancer Network.

Factors Associated with Delayed Hospital Arrival of Patients Presenting with Acute Myocardial Infarction: A Cross-Sectional Study in Bangladesh

Delay in seeking medical care of the patients with acute myocardial infarction (AMI) could affect the outcome. Therefore, it is important to recognize and reduce pre-hospital in initiating treatment of these patients. The objective of the study was to evaluate the factors associated with delayed hospital arrival of patients with AMI. This cross-sectional study was carried out among 385 patients with AMI attended in the Department of Cardiology, Dhaka Medical College Hospital (DMCH), Dhaka, Bangladesh. The delay in arrival to the hospital was recorded along with socio-demographic data, conditions of the patients during onset and other relevant data. The mean age of the patients 59.7±9.9 years with a male-female ratio of 2.4:1. About 22% of patients with AMI arrived at the hospital within 6 hours of symptoms onset and only around 13% arrived within 2 hours of onset of symptoms. Comparatively younger (p=0.037), unmarried (p=0.008) and Muslim (p=0.008) patients were more likely to present for hospital care sooner (p=0.037). Patients coming from upper middle class of socioeconomic status (p<0.001) and those with college or post college level of education (p<0.001) were more likely to present earlier for hospital care. Prehospital delay was larger in non-manual worker patients (p<0.001) as well as in patients with onset of chest pain during rest period (p<0.001) and while at home (p<0.001). Pre-hospital delay was shorter in patients with onset of chest pain from 12am to 6am and 6am to 12pm (p<0.001). Lack of awareness of AMI symptoms and benefits of its early treatment, long distance and mode of transport were shown as the most common causes of delayed arrival of patients at hospital (p<0.001). This study has identified the factors associated with AMI in context of Bangladesh. Effective measures including increasing awareness of AMI symptoms should be taken for better outcome of the patients.

Estimating the health care costs of non-melanoma skin cancer in Saskatchewan using physician billing data

Introduction

Given the high occurrence and morbidity of non-melanoma skin cancer (nmsc), its economic burden on the Canadian health care system is a cause for concern. Despite that relevance, few studies have used patient-level data to calculate the cost of nmsc. The objective of the present study was to use physician billing data to describe the health care costs and service utilization associated with nmsc in Saskatchewan.

Methods

The Saskatchewan Cancer Agency's cancer registry was used to identify patients diagnosed with nmsc between 2004 and 2008. Treatment services and costs were based on physician billing claims, which detail physician services performed in an outpatient setting. Total and annual outpatient costs for nmsc and mean outpatient cost per person were calculated by skin cell type, lesion site, and geographic location. Service utilization and costs by physician specialty were also explored.

Results

Total outpatient costs grew 12.08% annually, to $845,954.98 in 2008 from $527,458.76 in 2004. The mean outpatient cost per person was estimated at $397.86. Differences in the cost-per-person estimates were observed when results were stratified by skin cell type ($403.41 for basal cell carcinoma vs. $377.85 for squamous cell carcinoma), lesion site ($425.27 for the face vs. $317.80 for an upper limb), and geographic location ($415.07 urban vs. $363.48 rural). Investigation of service utilization found that 92.14% of treatment was delivered by general practice and plastic surgery/otolaryngology physicians; dermatology delivered only 6.33% of services.

Conclusions

Our results underestimate the direct costs of nmsc because inpatient services and non-physician costs were not included in the calculations. The present research represents a first step in understanding the cost burden of nmsc in Saskatchewan.

Genome sequence of an Australian strain of canid alphaherpesvirus 1

OBJECTIVE

Characterisation of a complete genome sequence of an Australian strain of canid alphaherpesvirus 1 (CHV-1) and its phylogenetic relationship with other varicellovirus species.

METHODS

Standard pathology and PCR methods were used to initially detect herpesvirus in hepatic tissue from an infected 4-week-old Labrador Retriever puppy. The complete CHV-1 genome was sequenced using next-generation sequencing technology followed by de novo and reference assembly, and genome annotation.

RESULTS

The CHV-1 genome was 125 kbp in length and contained 74 predicted open reading frames encoding functional proteins, all of which have counterparts in other alphaherpesviruses. Phylogenetic analysis using the DNA polymerase gene revealed that the newly sequenced CHV-1 clustered with canid alphaherpesvirus isolated from the UK and shared a 99% overall nucleotide sequence similarity.

CONCLUSION

This is the first complete genome of an Australian strain of CHV-1, which will contribute to our understanding of the genetics and evolution of herpesvirus.

Recommendations on managing lenvatinib and everolimus in patients with advanced or metastatic renal cell carcinoma

INTRODUCTION

There are several second-line treatment options for patients with renal cell carcinoma after first-line failure of a tyrosine kinase inhibitor, especially with the recent approvals of cabozantinib, nivolumab, and the lenvatinib plus everolimus combination. A lack of reliable biomarkers and an overall lack of prospective head-to-head comparisons make it a challenge to choose a second-line treatment in the clinic. Areas covered: In this review/meta-opinion, we describe the safety profile of the lenvatinib plus everolimus combination in renal cell carcinoma. The combination of lenvatinib plus everolimus has achieved the highest rates of objective responses and the longest progression free and overall survival in cross-comparison trials. At the same time, the safety profile of this combination, including the rate of total and severe adverse events, the percentage of dose reductions required, and the rate of treatment discontinuation, was less favorable compared with available monotherapy options, suggesting that better management could help to maximize the activity of this combination while protecting patients from undue harm. Expert opinion: Herein, we aim to postulate multidisciplinary recommendations on the advice to offer to patients and caregivers before starting treatment and how to manage the combination from the perspective of daily clinical practice.

Impact of travel distance on access to treatment and survival in patients with metastatic colorectal cancer prescribed bevacizumab plus chemotherapy

INTRODUCTION

Given Saskatchewan's size and low population density outside of city centres, many rural and remote residents have issues accessing regional oncology services. We performed a study to determine whether travel distance to cancer treatment centres affects first-line treatment accessibility and survival in patients with metastatic colorectal adenocarcinoma.

METHODS

Retrospective chart review of patients with stage IV metastatic colorectal adenocarcinoma collected by the Saskatchewan Cancer Agency registry between June 1, 2009, and June 30, 2013. Patients were categorized as living within 100 km of or more than 100 km from the nearest cancer treatment centre offering bevacizumab plus first-line chemotherapy. Main outcome measures were differences in first-line treatment accessibility and overall survival estimates (calculated via the Kaplan-Meier method) between cohorts.

RESULTS

Of the 252 included patients, 91 (36.1%) resided more than 100 km from a cancer treatment centre. Accessibility of standard single-agent and combination chemotherapy in the first-line setting, when not prescribed in conjunction with bevacizumab, was comparable between cohorts. Patients living within 100 km of a treatment centre and those living more than 100 km from a treatment centre had comparable access to bevacizumab in conjunction with first-line chemotherapy (57 [62.6%] v. 116 [72.0%] patients; p = 0.1) and similar median overall survival (18.1 v. 25.0 mo; p = 0.2).

CONCLUSION

Neither access to bevacizumab treatment nor survival times for metastatic colorectal adenocarcinoma were significantly different between the cohorts. This suggests that health care providers in Saskatchewan may be doing well in arranging timely access to advanced oncology centres. Future studies with a larger sample, different tumour types or changes to the definition of remoteness are indicated.

Review of psittacine beak and feather disease and its effect on Australian endangered species

BACKGROUND

Since it was first described in the early 1980s, psittacine beak and feather disease (PBFD) has become recognised as the dominant viral pathogen of psittacine birds in Australia. Our aim was to evaluate and review the effect of PBFD and its position as a key threatening process to Australian psittacine bird species. We review the origin/evolutionary pathways and potential threat of PBFD to endangered psittacine bird populations and captive-breeding flocks.

CONCLUSIONS

The most recent beak and feather disease virus (BFDV) phylogenetic analyses indicate that all endangered Australian psittacine bird species are susceptible to, and equally likely to be infected by, BFDV genotypes from a range of host psittacine species. Management of the disease in captive-breeding programs has relied on testing and culling, which has proven costly. The risk of PBFD should be considered very carefully by management teams contemplating the establishment of captive-breeding flocks for endangered species. Alternative disease prevention tools, including vaccination, which are increasingly being used in wildlife health, should be considered more seriously for managing and preventing PBFD in captive flocks of critically endangered species.

Serum Copper Status among Acute Myocardial Infarction Male Patients in Bangladesh

This case control study was carried out in the Department of Biochemistry, Mymensingh Medical College in collaboration with the Department of Cardiology, Mymensingh Medical College Hospital, Mymensingh, Bangladesh from January 2015 to December 2015. The aim of the study was to explore the serum copper status among acute myocardial infarction (AMI) patients as a means to monitor the possibility of management of these patients. A total of 120 subjects were included in this study. Among them 60 were diagnosed AMI patients denoted as case group and 60 were normal healthy individuals denoted as control group. Serum copper determined by colorimetric method from each sample. Statistical analysis was performed by SPSS windows package, version 20. Among the study groups the mean serum copper levels were 150.30±26.16 and 103.65±9.38 in case and control group respectively. Analysis showed that the mean serum copper level was significantly (p<0.01) increased in AMI patients in comparison to that of control group.

Epigenetic silencing of CREB3L1 by DNA methylation is associated with high-grade metastatic breast cancers with poor prognosis and is prevalent in triple negative breast cancers

Background

CREB3L1 (cAMP-responsive element-binding protein 3-like protein 1), a member of the unfolded protein response, has recently been identified as a metastasis suppressor in both breast and bladder cancer.

Methods

Quantitative real time PCR (qPCR) and immunoblotting were used to determine the impact of histone deacetylation and DNA methylation inhibitors on CREB3L1 expression in breast cancer cell lines. Breast cancer cell lines and tumor samples were analyzed similarly, and CREB3L1 gene methylation was determined using sodium bisulfite conversion and DNA sequencing. Immunohistochemistry was used to determine nuclear versus cytoplasmic CREB3L1 protein. Large breast cancer database analyses were carried out to examine relationships between CREB3L1 gene methylation and mRNA expression in addition to CREB3L1 mRNA expression and prognosis.

Results

This study demonstrates that the low CREB3L1 expression previously seen in highly metastatic breast cancer cell lines is caused in part by epigenetic silencing. Treatment of several highly metastatic breast cancer cell lines that had low CREB3L1 expression with DNA methyltransferase and histone deacetylase inhibitors induced expression of CREB3L1, both mRNA and protein. In human breast tumors, CREB3L1 mRNA expression was upregulated in low and medium-grade tumors, most frequently of the luminal and HER2 amplified subtypes. In contrast, CREB3L1 expression was repressed in high-grade tumors, and its loss was most frequently associated with triple negative breast cancers (TNBCs). Importantly, bioinformatics analyses of tumor databases support these findings, with methylation of the CREB3L1 gene associated with TNBCs, and strongly negatively correlated with CREB3L1 mRNA expression. Decreased CREB3L1 mRNA expression was associated with increased tumor grade and reduced progression-free survival. An immunohistochemistry analysis revealed that low-grade breast tumors frequently had nuclear CREB3L1 protein, in contrast to the high-grade breast tumors in which CREB3L1 was cytoplasmic, suggesting that differential localization may also regulate CREB3L1 effectiveness in metastasis suppression.

Conclusions

Our data further strengthens the role for CREB3L1 as a metastasis suppressor in breast cancer and demonstrates that epigenetic silencing is a major regulator of the loss of CREB3L1 expression. We also highlight that CREB3L1 expression is frequently altered in many cancer types suggesting that it could have a broader role in cancer progression and metastasis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-016-0672-x) contains supplementary material, which is available to authorized users.

Mixture models for analyzing product reliability data: a case study

In the case of manufactured products, there are situations where some components of a product are produced over a period of time by collecting items from different vendors, using different raw materials, machines, and manpower. The physical characteristics and the reliabilities of such components may be different, but sometimes it is difficult to distinguish them clearly. In such situations, mixtures of distributions are often used in the analysis of reliability data for these components. Here a twofold Weibull-Weibull mixture model is applied to analyze product reliability data that consist of both failure and censored lifetimes. The Expectation-Maximization (EM) algorithm is used to find the maximum likelihood estimates of the model parameters. As a case study, it analyses an Aircraft component (Windshield) failure data and various characteristics of the mixture model, such as the reliability function, B10 life, mean time to failure, etc., are estimated to assess the reliability of the component. Simulation studies are performed to investigate the properties and uses of the proposed method.

Hyperglycemia is a predictor of mortality and morbidity in low birth weight newborn

Early onset of hyperglycemia is common among low birth weight neonates. Increased risk for death and major morbidities has been observed among hyperglycemic low birth weight infants. This prospective observational study was done to find out hyperglycemia as a predictor of increased morbidity and mortality in the low birth weight sick newborn and was conducted among the hospitalized newborn of Special Care Baby Unit (SCABU), BIRDEM hospital, Dhaka, Bangladesh from July 2009 to December 2009. A total of 198 LBW neonates were included in this study. One third (30.8%) LBW neonates were found hyperglycemic. The mean gestational age was 33.2±3.6 weeks and mean birth weight was 1535.8±780gm in the hyperglycemic neonates. In this study, highest prevalence of hyperglycemia was observed in birth weight <1000gm (38.46%) and in gestational age ≤28 weeks (46.15%). Apnoea, confirmed sepsis and suspected sepsis, confirmed necrotizing enterocollitis (NEC) and neonatal jaundice showed statistically significant association with hyperglycemia than that of non hyperglycemic group. Mortality of neonates in hyperglycemic group was higher (31.15%) than that of non hyperglycemic neonates (10.22%) and the difference in mortality between two groups were found statistically significant (p<0.002). From this study it can be concluded that hyperglycemia in early neonatal period is related to increased morbidity and mortality in low birth weight newborn.

Abstract 156: Prognostic significance of distance travelled to the cancer center in women treated with adjuvant trastuzumab

Background: Adjuvant trastuzumab therapy (ATT) in women with HER2 positive breast cancer has significantly improved survival. The current standard duration of ATT is one year. In order to prevent symptomatic cardiac dysfunction, periodic cardiac monitoring is recommended during ATT. Rural residents have to travel in excess of several hundred kilometers both for cardiac monitoring and treatment. The study aims to determine relationship between distance travelled to the cancer center and disease free survival (DFS) and overall survival (OS) in women with HER2 positive breast cancer.

Methods: Retrospective cohort study of women with early stage HER2 positive breast cancer treated in the province of Saskatchewan from 2005 to 2009. The study cohort was divided into two groups: group I (distance travelled &lt;100 km) and group II (distance travelled 100 km). Kaplan-Meier methods were used for survival estimation and Log Rank testing was done for survival comparison. Cox proportional hazard models were performed and various clinico-pathological variables were examined for their prognostic significance.

Results: A total of 211 eligible women with median age of 54 yrs (range: 27-80) were identified. 70% were postmenopausal, 52% had node positive disease and 60% had ER or PR positive disease. 57% women were rural residents. A statistically significant difference was noted between the 2 groups with respect to age, rural residence, comorbid illness and delay in start of therapy. All women received adjuvant chemotherapy and ATT. 97% women completed adjuvant chemotherapy and 83% completed planned ATT. During the median follow-up period of 37.1 months, 30 women developed recurrent disease and 26 died. Median DFS of Group II was 63.09 months and has not reached in Group I (p=0.5). Median OS of both groups has not reached. 5 years estimated DFS of group I was 77% compared with 57% in Group II (p=0.5). ER/PR negative disease, hazard ratio (HR) 2.53 (95% CI: 1.14-5.64) and discontinuation of ATT, HR 2.3 (95% CI: 1.06-5.00) were significantly correlated with an increased risk of recurrence. With respect to survival younger age, HR 5.33 (95% CI: 1.72-16.52); ER/PR negative tumors, HR 6.6 (95% CI: 2.23-19.37); and premenopausal status, HR 8.18 (95% CI: 2.27-29.51) were correlated with an increased mortality.

Conclusions: Although there was a trend toward increased risk of recurrence in women travelled longer distance, it was not statistically significant. Younger age, premenopausal status, ER/PR - tumors and discontinuation of ATT were correlated with inferior outcomes.

Citation Format: Sarah Roberts, Sabuj Sarker, Richard Lee-Ying, Charanpreeti Ubhi, Shahid Ahmed. Prognostic significance of distance travelled to the cancer center in women treated with adjuvant trastuzumab. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 156. doi:10.1158/1538-7445.AM2013-156

PATHOLOGICALSTUDY ON COLIBACILLOSIS IN CHICKENS AND DETECTION OF ESCHERICHIA COLI BY PCR

    The aim of the present study was to detect the pathogenic Escherichia coli (E. coli) through pathological study of the colibacillosis affected birds. These isolated E. coli were further confirmed by PCR using specific primer. For this purpose, a total of 20 swabs (10 from lung and 10 from intestine of 10 dead birds) were collected in sterile nutrient broth. The histopathological samples were collected in 10% buffered neutral formalin. The used methods were histopathology, isolation and identification of E. coli by conventional methods and as well as by PCR method. A total of 10 isolates of E. coli from 20 swabs of lung and intestine was characterized by conventional routine methods of bacteriology. Gross pathological lesions of all lungs in the present investigation were congested and consolidated. Duodenum showed congestion and hemorrhages with excess mucus in the luminal surface of it. Microscopically, all the lungs showed severe congestion, infiltration of heterophils, macrophages and lymphocytes in the wall of bronchus as well as in the peribronchial alveoli. E. coli infected all the duodenum showed severe infiltration of leukocytes mainly heterophils, lymphocytes and macrophages in the submucosa of the duodenal wall. In this study, DNA of 8 isolates out of 10 isolated E. coli organisms was amplified by PCR using ECO-f and ECO-r primer targeting 16S ribosomal DNA and found 585 bp amplicon which is specific for E. coli with enteroinvasive type confirmed by histopathological lesions in duodenum. Further investigation should be focused on serotyping and detection of genes of E. coli which are responsible for pathogenicity of the organism.DOI = http://dx.doi.org/10.3329/bjvm.v9i1.11205Bangl. J. Vet. Med. (2011). 9(1): 17-25 

Evaluating repeated patient handling injuries following the implementation of a multi-factor ergonomic intervention program among health care workers

OBJECTIVE

The objective of this study was to evaluate repeated patient handling injuries following a multi-factor ergonomic intervention program among health care workers.

METHODS

This was a quasi-experimental study which had an intervention group and a non-randomized control group. Data were collected from six hospitals in Saskatchewan, Canada from September 1, 2001 to December 1, 2006.

RESULTS

A total of 1,480 individuals who had a previous injury were eligible for the study. Medium and small size hospitals in the intervention group had significantly fewer repeated injuries than in the control group. Multivariate analysis showed that the intervention group had 38.1% lower odds of having repeated injury compared to the control group, after adjusting for hospital size.

CONCLUSIONS

The work-related repeated injury after a multi-factor intervention program was reduced. The synergistic relationships between components of multi-factor intervention and applicability of injury prevention programs to different settings need to be further explored.

IMPACT ON INDUSTRY

Implementing a multi-factor program with the right equipment and training can lower the risk of injury among health care workers.

Maternal over weight and obesity: its effect on pregnancy outcome

Obesity in pregnancy remains a significant health problem that result in physiological, emotional, social and economic consequences on woman, their families and society. Obesity is considered one of the nutritional problems complicating pregnancy in our country. This study was conducted in antenatal clinic at out patient department of Obstetrics & Gynecology, BIRDEM Hospital, one of the countries largest tertiary level hospitals, during January 2007 to December 2008. During the study period of two years, a total no. of 100 cases were enrolled in two groups. Out of this 50 were control and 50 were over weight and obese. In this study, Mean of height, weight and BMI of the over weight and obese group were 5.21±0.21, 79.35±13.66, 32.36±4.76 respectively. The Mean of birth weight, APGAR score after 1 min and after 5 min of the over weight and obese group were 3.07±0.75, 7.10±1.11, 9.92±0.98 respectively and in normal weight group were 2.74±0.55, 7.40±1.56, 9.92±1.83 respectively. There was significant difference in birth weight, APGAR score after 1 min between the groups (p<0.05) but there was no significant difference in APGAR score after 5 min between groups (p>0.05). Regarding the fetal outcome in this study, 20% of the over weight and obese group delivered macrosomic baby in comparison to only 4% in the normal weight group. On the other hand 46% of the case group had to refer their babies to the neonatal unit in comparison to only 12% in the control group. Gestational Diabetes Mellitus (GDM) (46%) and Preeclampsia (44%) developed more in obese group. Eighty eight (88%) of obese and overweight mother experienced in caesarean delivery. Asphyxia, Respiratory Distress Syndrome (RDS), congenital anomaly and prenatal death were more in the over weight and obese group than normal weight group. Thus, overweight and obesity has got significant deleterious effect on maternal and perinatal outcomes of pregnancy.

Abstract PD05-12: Combination of Notch Inhibitor MK-0752 and Endocrine Therapy for Early Stage ERα + Breast Cancer in a Presurgical Window Pilot Study

Background: Breast tumor initiating cells (TIC) use Notch receptors/ligands with other pathways for self renewal, resulting in tumor proliferation and progression. We showed that Notch inhibition with gamma secretase inhibitors (GSI) potentiates the effects of tamoxifen (tam) in xenografts (Rizzo et al. Cancer Res 2008). It is unknown whether GSIs plus endocrine therapy result in modulation of Notch and other proliferation markers in human breast cancer. Our objective was to add short exposure of the GSI MK-0752 to ongoing tam or letrozole (letr) during the presurgical window to determine 1) feasibility, 2) safety/tolerance, and 3) impact on biomarkers. We report the initial cohort of this pilot study (ClinTrials. gov NCT00756717).

Methods: Patients (pts) with early stage ERα + breast cancer were treated with 25 days of tam or letr. On day 15 MK-0752 was added to endocrine therapy (350 mg orally 3 days on, 4 days off, 3 days on), with definitive surgery day 25. Formalin fixed, paraffin embedded biopsies were obtained at baseline, day 14 and final surgery, with histologic confirmation of tumor content &gt;50% and RNA extraction by standard methods. Q-PCR was done for Notch1, Notch3, Notch4, Deltex, Jagged1, c-myc, HEY1, HEY2, HES1, PS2, C-Myc, Cyclin A2, NOXA (pro-apoptotic protein), Ki67, Dicer-1, RPL13 (internal control). Ct averages for 3 replicates were used and mRNA levels were calculated by the 2ΔΔCt method. Baseline gene expression levels were used as comparators for days 14 and 25 levels in each pt. The first cohort of 10 pts was analyzed to determine if enough signals were present to justify expanding the cohort at this dose to 20 pts and possibly test a second cohort on an alternate MK-0752 dose/schedule. Results: The initial cohort of 10 pts completed all therapy (4 tam, 6 letr), all biopsies and definitive surgery on schedule. One other pt withdrew prior to starting MK-0752 due to hypertension. Toxicity was minimal: grade 1 periorbital edema/cough, nausea, and axillary paresthesias in 1 pt each; grade 1 facial rash, 2 pts; and grade 2 fatigue, 1 pt. There was no diarrhea or surgical complications. Significant changes occurred in molecular marker levels after MK-0752 plus tam/letr (day 25) vs. end of tam/letr alone (day 14) as follows: Ki67 mRNA decreased in 9/10 pts; Notch4 decreased, 10/10; NOXA increased, 6/10; and Notch1 decreased, 6/10. Other markers showed inter-individual variations and will be presented, along with results of the global gene expression profiling (in progress). Conclusions: The addition of a short exposure of the GSI MK-0752 to ongoing endocrine therapy was feasible, safe, and well tolerated in pts with ERα + early breast cancer prior to definitive surgery. It results in anti-proliferative and pro-apoptotic effects at the molecular level. Notch4, which plays a key role in breast TIC, was the most consistent molecular marker of response in this setting. This suggests a potential anti-TIC effect of this combination and a role in overcoming endocrine resistance. Accrual to the expanded cohort is underway. If findings are confirmed, the second study with alternate MK-0752 dose/schedule may commence. Funding: Swim Across America, Inc. (clinical trial costs); Merck (drug supply, profiling)

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr PD05-12.

Prevalence of obesity among affluent school children in Dhaka

A cross sectional study was conducted in September 2006 in one of the private schools in Dhaka, Bangladesh to see the prevalence of obesity among affluent school children and adolescents. Informed consent was taken from school authority to take anthropometric measurement of all school children. Standing height was measured with a stadiometer and weight with a bathroom scale. Waist and hip circumference were measured with a measuring tape. The body mass index (BMI) was calculated using weight in kilogram/(height in meter)2 formula. Obesity was defined as BMI≥95th percentile for age and sex, over weight as BMI≥85th percentile for age and sex, normal weight as BMI between 5th and 84th percentile and underweight as BMI <5th percentile. Official centers for disease control (CDC) growth chart for boys and girls age 2-20 years was used. Children and adolescents were divided into group 1(3-5 years), Group 2(6-9years), group 3(10-13 years) and group 4(14-18 years). There were a total of 468 children and adolescents (male 266, female 202). In group 1 there were 110 children, in group 2 there were177 children, in group 3 and 4 there were 149 and 32 adolescents respectively. The prevalence of obesity was 17.9%, higher among males (19.9%), compared to females (15.3%). Obesity was highest (27.7%) in group 2, 14.5% in group 1, 10.7% in group 3 and 9.4% in group 4.

Antioxidant enzymes in brackishwater oyster, Saccostrea cucullata as potential biomarkers of polyaromatic hydrocarbon pollution in Hooghly Estuary (India): seasonality and its consequences

Use of antioxidant enzymes as biomarkers often becomes a complicated process at application level because they show considerable seasonal fluctuation due to both natural and biological factors. In this study, we studied the consequences of seasonal variation of antioxidant enzymes [catalase (EC 1.11.1.6), superoxide dismutase (SOD, EC 1.15.1.1), glutathione peroxidase (GPX, EC 1.11.1.9) and microsomal NADPH-DT diaphorase (EC 1.6.99.2)] in the digestive gland of wild brackishwatcr oysters, Saccostrea cucullata for biomonitoring against polyaromatic hydrocarbon (PAH) contamination in Hooghly Estuary, north-eastern coast of India. As a general trend, maximum antioxidant enzyme activities were detected in pre-monsoon period or summer (March-June) followed by a gradual decrease during monsoon (July-October) with a minimum in post-monsoon period or winter (November-February) and this pattern was similar to tissue concentrations of PAHs also. The physiological fluctuations of the antioxidant defense systems were inversely-related to the lipid peroxidation indicating an enhanced susceptibility of oyster tissues to oxidative stress during post-monsoon or winter period. However, the oysters from polluted populations exhibited consistent very high PAHs load in their tissues as well as significant increases in the activities of antioxidant enzymes than in non-polluted populations in all three seasons. The results indicated that the antioxidant enzymes, catalase, SOD and microsomal NADPH-DT diaphorase in digestive gland of S. cucullata could be useful biomarkers of PAHs contamination. It also emphasized that seasonal variation of potential biomarkers like such enzymes should be incorporated into interpretation of biomonitoring studies by the use of appropriate controls and identical treatment in analysis of polluted and non-polluted samples.

Seasonal variation of antioxidant and biotransformation enzymes in barnacle, Balanus balanoides, and their relation with polyaromatic hydrocarbons

Seasonal variations in the antioxidant enzymes (catalase, superoxide dismutase [SOD], NADH-DT diaphorase), biotransformation enzyme, glutathione-S-transferase (GST) and microsomal lipid peroxidation in digestive tissue of barnacle, Balanus balanoides, from polluted and non-polluted populations have been evaluated. Relationships with accumulated polyaromatic hydrocarbon (PAH) concentration in barnacle tissues and environmental parameters (water temperature, salinity, dissolved oxygen concentration, water pH) were determined. As a general trend, maximum antioxidant enzyme and GST activities were detected in the pre-monsoon period or summer (March-June) followed by a gradual decrease during the monsoon (July October) with a minimum in the post-monsoon period or winter (November February). This pattern was similar to tissue concentrations of PAHs, resulting in a significant positive correlation with antioxidant enzymes, mainly catalase and SOD. Microsomal lipid peroxidation exhibited an almost reverse trend of seasonal variation to that of antioxidant enzyme activities indicating an enhanced susceptibility of barnacle tissues to oxidative stress. Among the environmental parameters, only water temperature seemed to have a significant effect on observed variations of antioxidant enzymes and GST activities. The barnacles from polluted and non-polluted populations exhibited seasonal differences in the activities of all the enzymes studied, particularly catalase, SOD and GST, suggesting the possibility of some biochemical adaptation in organisms from a chronically polluted environment. The results indicated that antioxidant defense components, catalase and SOD, are sensitive parameters that could be useful biomarkers for the evaluation of contaminated aquatic ecosystems. The results also suggested the potentiality of barnacle, B. balanoides, as a bioindicator organism against organic pollution.

Revised translation start site for secM defines an atypical signal peptide that regulates Escherichia coli secA expression

The secretion-responsive regulation of Escherichia coli secA occurs by coupling its translation to the translation and secretion of an upstream regulator, secM (formerly geneX). We revise the translational start site for secM, defining a new signal peptide sequence with an extended amino-terminal region. Mutational studies indicate that certain atypical amino acyl residues within this extended region are critical for proper secA regulation.

Snake venom hemorrhagins

Viperine and crotaline snake venoms contain one or more hemorrhagic principles called hemorrhagins. These are zinc-containing metalloproteases characterized by the presence of a protease domain, with additional domains in some of them. They act essentially by degrading the component proteins of basement membrane underlying capillary endothelial cells. The toxins also act on these cells causing lysis or drifting apart, resulting in hemorrhage per rhexis or per diapedesis. Some of these toxins have been found to exert additional effects such as fibrinogenolysis and platelet aggregation that facilitate hemorrhage. The structural and functional features of this class of toxins have been discussed in this review in an attempt to get a better understanding of their toxicity. This can be of immense therapeutic value in the management of snake venom poisoning, as hemorrhagins are among the major lethal factors in snake venom.

Regulation of Escherichia coli secA by cellular protein secretion proficiency requires an intact gene X signal sequence and an active translocon

secA is translationally regulated by the protein secretion proficiency state of the Escherichia coli cell. This regulation was explored by making signal sequence mutations in the gene upstream of secA, gene X, which promotes secA translational coupling. Gene X signal sequence mutants were constitutive for secA expression, while prlA alleles partially restored secA regulation. These results show that interaction of the pre-gene X protein with the translocon is required for proper secA regulation. Furthermore, gene X signal sequence mutations disrupted secA regulation only in the cis configuration. We propose that nascent pre-gene X protein interacts with the translocon during its secretion to constitute the secretion sensor.

Single dose vitamin A treatment in acute shigellosis in Bangladesh children: randomised double blind controlled trial

OBJECTIVE

To evaluate the efficacy of a single large oral dose of vitamin A in treating acute shigellosis in children in Bangladesh.

DESIGN

Randomised double blind controlled clinical trial.

SETTING

Dhaka Hospital, International Centre for Diarrhoeal Disease Research, Bangladesh.

SUBJECTS

83 children aged 1-7 years with bacteriologically proved shigellosis but no clinical signs of vitamin A deficiency; 42 were randomised to treatment with vitamin A and 41 formed a control group.

INTERVENTION

Children were given a single oral dose of 200,000 IU of vitamin A plus 25 IU vitamin E or a control preparation of 25 IU vitamin E.

MAIN OUTCOME MEASURES

Clinical cure on study day 5 and bacteriological cure.

RESULTS

Baseline characteristics of the subjects in the two treatment groups were similar. Significantly more children in the vitamin A group than in the control group achieved clinical cure (19/42 (45%) v 8/14 (20%); chi 2 = 5.14, 1 df, P = 0.02; risk ratio = 0.68 (95% confidence interval; 0.50 to 0.93)). When cure was determined bacteriologically, the groups had similar rates (16/42 (38%) v 16/41 (39%); chi 2 = 0.02, 1 df, P = 0.89; risk ratio = 0.98 (0.70 to 1.39)).

CONCLUSIONS

Vitamin A reduces the severity of acute shigellosis in children living in areas where vitamin A deficiency is a major public health problem.

Clofilium-induced block of delayed rectifier type K+ current in atrial tumor cells (AT-1 cells)

Atrial tumor myocytes derived from transgenic mice (AT-1 cells) have been shown to express mRNAs encoding cardiac K+ channels and display a cardiac electrophysiological phenotype. The major K+ current is the rapid component of the delayed rectifier (I(kr)). The purpose of the study was to characterize the mode of action of a class III anti-arrhythmic agent (C3A), clofilium, in these cells to elucidate further the mechanism and functional consequence of block. We show that clofilium blocks this I(kr) in a dose-dependent manner with IC50 of 1.25 microM. Clofilium induced block was irreversible for higher concentrations (> or = 50 microM) and partially reversible for lower doses. The reversal potential for this current was -77.5+/-1.5 mV. The block is voltage dependent and the drug probably binds the channel in the open state.

Clinical and laboratory evaluation of powered electric toothbrushes: laboratory determination of relative abrasion of three powered toothbrushes

Previously established data on average forces applied to various brushing instruments during in vivo toothbrushing were incorporated into a laboratory abrasion model. The apparatus included a specially constructed and standardized brushing machine and utilized an acrylic resin substrate. Three powered brushing instruments (Rota-dent, Interplak and Braun Oral-B Plaque Remover) and a manual toothbrush (Oral-B P40), were compared in this model. The system demonstrated excellent precision and could distinguish between brushing instruments with as little as 10% difference in abrasivity. It was found that brushing abrasivity increased in the order of Rota-dent < Braun < Interplak.

Nuclear DNA content of fine needle aspirates of invasive ductal carcinomas of the breast

Patients with aggressive breast cancers benefit from chemotherapy prior to surgery. If the biology of the breast cancers were better characterised pre-operatively, more patients at risk could be offered chemotherapy. We have assessed nuclear DNA content of fine needle aspirates (FNA) of 103 invasive ductal breast cancers and compared this to tumour size, node status and histological grade. Median follow-up was 18 months so no prognostic studies were made. Diploid and non-diploid tumours were distributed equally in node negative and positive patients. However non-diploidy status increased in line with known prognostic markers of tumour size and histological grade. This suggests that ploidy might contribute to the pre-operative assessment of prognosis. We conclude that nuclear DNA of breast cancer FNAs may be of value in the pre-operative biological assessment of breast cancer patients.

Clinical and laboratory evaluation of powered electric toothbrushes: laboratory determination of relative interproximal cleaning efficiency of four powered toothbrushes

The clinical brushing data from the paper entitled, Clinical and Laboratory Evaluation of Powered Electric Toothbrushes: In Vivo Determination of Average Force for Use of Manual and Powered Toothbrushes, by Boyd et al. in this Special Issue, were incorporated into a laboratory cleaning model. Utilizing a standardized brushing machine and a methyl methacrylate substrate, four powered brushing instruments were tested for cleaning efficiency: Rota-dent. Braun Oral-B. Interplak and Sonicare, and a manual toothbrush (Oral-B P40). The Sonicare powered brushing instrument was tested at the manufacturer's recommended brushing force of 0.5 N as well as a calculated force of 1.0 N. The results showed that the Rota-dent was more efficient (p < 0.01-0.001) in removing stain from both flat and interproximal surfaces than any of the other tested brushes. These results, together with those reported by McLey, et al. in Clinical and laboratory Evaluation of Powered Electric Toothbrushes: Laboratory Determination of Relative Abrasion of Three Powered Toothbrushes in this Special Issue, demonstrate that the rotary action Rota-dent instrument has the most efficient combination of low abrasion and high cleaning efficiency of the four powered brushes and the manual brush when all instruments were tested using clinically documented pressures.

Clinical and laboratory evaluation of powered electric toothbrushes: relative degree of bristle end-rounding

Toothbrush bristles with sharp edges have been postulated to represent a greater threat to dental tissues than end-rounded bristles. This study evaluated the effect of both in vivo and laboratory use on bristle wear rate, tip geometry and in vitro abrasivity. Three soft manual brushes (Oral-B P40, Crest Complete and Butler GUM) and one powered brush (Rota-dent) were tested. The results of this study show that the wear rate varied directly with brushing load and amount of dentifrice, and inversely with bristle diameter. Despite the initial geometry, a flat tip with rounded rims was typically observed after only 30 minutes of manual or Rota-dent brush use. There was no statistical difference in in vitro abrasion for new brushes versus used brushes.

Ryanodine induced block of a cloned human cardiac potassium channel

The effects of ryanodine in a cloned human cardiac potassium channel (hKvl.5) expressed in a stable mouse L cell line was studied using whole cell voltage clamp technique. Ryanodine in a dose dependent manner (10(-7) - 10(-5) M) reduced the peak current as well as the current at the end of a 250 ms pulse. Dose response data fitted to a Hill equation yielded IC50 of 1.2 microM. The degree of block was not voltage dependent. Peak current was reduced from 43.6 +/- 12.5% at 10(-5) M to 11.3 +/- 4.8% at 10(-7) M ryanodine. Ryanodine reduced the tail current amplitude without changing the time course relative to the control. The inhibition was only partially reversible at concentrations below 10(-6) M.

Assessment of gastric acid output by H2 breath test

BACKGROUND

The standard method to measure gastric acid secretion is the aspiration of gastric juice. A noninvasive breath test after application of magnesium has been proposed. The aim of this study was to modify the method, to possibly improve the discriminatory value of the test in comparison with intubation tests.

METHODS

We measured the time course of the reaction of magnesium and gastric acid in vitro and determined the gastric hydrogen kinetics in humans by insufflation of hydrogen into the stomach and measuring its reappearance in the exhaled air. Thereafter, a comparison of the breath test and the intubation test was done in 10 healthy volunteers in different secretory states.

RESULTS

After hydrogen insufflation 31.4% reappeared in 90 min (16.3% exhaled, rest belched). Discriminant analysis showed that the intubation test had a good discriminatory power. On the other hand, the breath test failed to distinguish between different secretory states (stimulation, inhibition, and intermediate).

CONCLUSION

Whereas the intubation test discriminated between high and low acid secretion, the breath test did not. This test therefore seems, at least as performed here, unsuitable as a diagnostic test of gastric acid secretion.

Dextrose-, adenosine- and magnesium-induced protective actions during anoxia and reperfusion in canine Purkinje tissue

1. The effects of dextrose, magnesium (Mg) and adenosine on membrane potential and force of contraction were studied in driven and overdriven canine cardiac Purkinje tissue. 2. Dextrose (50 mmol/L) and adenosine (4-6 mmol/L) both showed protective action (the latter to a lesser extent) against simulated anoxia and reperfusion-induced arrhythmias, increased force of contraction transiently on reperfusion, and the former sustained the increase in force to a lower level as long as it was in the superfusing solution. 3. Dextrose (50 mmol/L) and Mg (5 mmol/L) restored overdrive-induced hyperpolarization during simulated anoxia. Adenosine was largely ineffective. 4. It was concluded that dextrose and adenosine (to a lesser extent) protect against arrhythmias by replenishing the critical intracellular pool of ATP which controls membrane transport of electrolytes such as K and Ca. Restoration of Na-K ATPase activity alone (as in the case of high Mg concentrations) is not sufficient to prevent arrhythmias.

Modulations of membrane potential oscillations with drive, calcium overload, ryanodine, and caffeine

The objective of this study is to determine the conditions that generate overdrive excitation and overdrive suppression in canine cardiac Purkinje tissue superfused in vitro. Drive-induced (3 Hz) perturbations in the membrane potential of a calcium overloaded (induced by strophanthidin) Purkinje fiber (from a canine heart) were differently modulated by caffeine and ryanodine. Whereas the postdrive oscillations in the membrane potential Vos (single or multiple oscillations in the diastole of the action potential) and/or spontaneous rate (postdrive suppression or postdrive excitation [PDE]) depended on the concentration of strophanthidin (PDE occurred at 2.5 x 10(-7) M, and Vos were seen variably at several concentrations), caffeine (2-3 mM) in the presence of a lower concentration of strophanthidin (1.25 x 10(-7) M) induced PDE. At these lower concentrations, either drug administered alone only induced Vos. On the contrary, the characteristic effects of ryanodine (10(-8) M) in the presence of strophanthidin (2.5 x 10(-7) M) were either a consistent postdrive suppression immediately or the induction of a pronounced afterdepolarization ([AD] a depolarization following the repolarization of the action potential) whose amplitude decreased with time and suppression. At higher concentrations of ryanodine (10(-5) M-10(-6) M) in a calcium overloaded tissue (strophanthidin, 1.25 x 10(-7) M) overdrive induced a pronounced AD in most cases, with subsequent depolarization and cessation of activity in less than 20 minutes. Ryanodine alone caused suppression of postdrive diastolic potential at lower concentrations (10(-9) M-10(-8) M), a pronounced AD (amplitude diminished with later drives), and suppression at higher concentrations (10(-6) M-10(-5) M).(ABSTRACT TRUNCATED AT 250 WORDS)

Different effects of reoxygenation on the electrical activity of ventricular muscle

Response of a hypoxic and acidotic (HA, with exogenous lactate) ventricular muscle tissue to subsequent reoxygenation in the absence of substrate (0 mM dextrose) was different from that of a Purkinje fiber. The K+ concentration in this solution (4.6 mM) was slightly higher than that in Tyrode solution (2.7 mM). The observed effects of reoxygenation of such a ventricular tissue were also variable. The ventricular muscle tissue exhibited the following different responses on reoxygenation after hypoxia and acidosis: (1) arrhythmias, without much depolarization of the membrane potential, (2) oscillatory after-potentials (OAPs) during the late diastole, which lessened in amplitude as the time of reoxygenation increased, but no arrhythmias, or (3) a pronounced slowed phase of repolarization (hump), but no arrhythmias. These different effects of reoxygenation did not occur if concentration of K+ in HA was very much higher than 4.6 mM. Common to these three different responses was the prolongation of the action potential durations during reoxygenation at the 50% and 90% levels of repolarization (APD50 and APD90) and a slight increase in the resting tension after 30-40 minutes of reoxygenation. Some of the observed responses of ventricular muscles were well mimicked by increasing extracellular calcium, but the different and variable effects of arrhythmias, OAPs, and prolonged APD require further analysis.