Heated and humidified high flow therapy (HHHFT) in extreme and very preterm neonates with respiratory distress syndrome (RDS): a retrospective cohort from a tertiary care setting in Pakistan

OBJECTIVE

To determine the role of heated humidified high flow therapy (HHHFT) as primary respiratory support in spontaneously breathing moderate-late, very and extreme preterm neonates with respiratory distress syndrome (RDS) at a tertiary care hospital from a developing country.

DESIGN

Retrospective cohort study.

SETTING

Neonatal intensive care unit of Indus Hospital and Health Network, Karachi, Pakistan.

PATIENTS

All preterm neonates with RDS and who received HHHFT as primary respiratory support were included retrospectively, while neonates with orofacial anomalies, congenital heart and lung diseases other than RDS, abdominal wall defects, encephalopathy, congenital pneumonia and received continuous positive airway pressure or invasive ventilation were excluded.

INTERVENTIONS

HHHFT as primary respiratory support for RDS.

MAIN OUTCOME MEASURES

Effectiveness, duration, failure rate and complications of HHHFT as a primary respiratory support in moderate-late, very and extremely preterm neonates were evaluated.

RESULTS

The cohort included 138 neonates during a period of 12 months. The median gestational age was 32 weeks, and the median birth weight was 1607 g. Grade 1-2 RDS was seen in 97%, surfactant instillation was done in 10.8% and HHHFT was provided in all the neonates as primary respiratory support. The total duration of HHHFT support was <1 week in 94% of neonates. Bronchopulmonary dysplasia and pneumothorax until discharge or death were observed in one neonate, haemodynamically significant Patent Ductus Artriosus (HsPDA) in two neonates and intraventricular haemorrhage Grade ≥2 in five neonates, while only one neonate died.

CONCLUSION

This study appears to show that HHHFT is a simple, safe, efficient and cheap mode of primary respiratory support that can be given to spontaneously breathing moderate-late, very and extremely preterm neonates with RDS, especially in low- or middle-income countries.

Comparison of Effect of Yoga versus Aerobic Exercise on Waist Circumference, Waist-Hip Ratio and Body Mass Index in Overweight and Obese Adult Individuals

Background Obesity is becoming serious global public health issue due to sedentary lifestyle and bad eating habits. Dietary and lifestyle practices are directly related to obesity, which can cause serious health problems like cardiac ailments, diabetes, and hypertension etc. Vast varieties of options are available for weight reduction including physical exercises, various diet plans and also the pharmacological agents. Physical activity improves the fitness of the individual and helps in reducing the ill effects of the obesity. Objective To compare the effects of Yoga and Aerobic Exercise on weight circumference, waisthip ratio (WHR) and body mass index (BMI) in overweight and obese individuals. Method An experimental study was started with purposive sampling. Sixty overweight and obese individuals from the community were divided equally into two groups, one group was given supervised yoga asana and the other group was given supervised aerobic exercise for 6 weeks. Waist circumference, waist hip ratio and body mass index were taken pre and post intervention. Result Statistically significant difference was seen in pre and post intervention value of waist circumference, waist hip ratio and body mass index in both the groups with the p value < 0.05. However there was no statistical significant difference noted in waist hip ratio in individuals performing aerobic exercises as p value was > 0.05. Conclusion Both the interventions showed significant reduction in waist circumference, waist hip ratio and body mass index, while better results were noted in the individuals performing yoga asanas.

Do health care physician need to risk their own lives? Time to change our own attitude towards recommended physical activity

Background

Cardiovascular diseases are the leading cause of death around the world,South Asian population are at higher risk of atherosclerotic coronary artery diseases (CAD) comparatively. There is a recommended physical activity level to prevent atherosclerotic cardiovascular disease (ASCVD). Health care professionals especially doctors are main advisors to prescribe the exercise protocols among general population. Hence we conducted a survey among doctors of Pakistan to identify their physical activity as well as their knowledge and attitude toward recommended physical activity.

Methodology

An online questionnaire was shared with doctors of various specialties working in private and public healthcare system of the Pakistan. It consisted of consent for participation,followed by information regarding demographic profile, preexisting co-morbid conditions, opinion regarding importance of physical activity to prevent ASCVD (5 point scale), perceived physical activity level (4 point scale), knowledge regarding ACC recommended physical activity level for primary prevention of ASCVD, lifestyle, and barriers in following recommended physical activity level. Collected data were entered and analyzed using SPSS version 21.0, participants were categorized into two groups as “cardiologists” and “non-cardiologists” and results were compared between the two groups.

Results

A total of 159 doctors participated in the survey, out of whom 97 (61%) were cardiologist and remaining 62 (39%) were affiliated with other specialties. Male participants (72.3%) were predominant and mean age was 30.44±23.16 years. More than 60% (61.6%) of the participants were free of preexisting co-morbid condition, most common ASCVD risk factor was positive family history (26.4%) followed by smoking (7.5%) and hypertension (6.3%). According to BMI, 21.4% (34) were obese and 40.3% (64) were overweight. A total of 74.8% (119) of the participants claimed to know about ACC recommended physical activity level but 65.5% (78) were actually aware of recommended 150 min of moderate-intensity or 75 min of vigorous-intensity aerobic activity level. According to the lifestyle activities only 26.4% (42) of the participants were found to follow the ACC recommended physical activity level per week, this proportion was same between cardiologists and non-cardiologists, 25.8% vs. 27.4% respectively. Lack of time from daily routine (71.7%) was found to be most commonly stated reason for physical in activeness followed by overburden/over stress at workplace (33.3%) and lack of resources (14.5%).

Conclusion

Knowledge and adherence to the ACC recommended physical actively level was poor among both cardiologists and non-cardiologists even after considering it important for the primary prevention of ASCVD. Majority of doctors were overweight and obese.Lake of time and resources and over stressed work life of doctors are the key barriers in following recommended physical activity level.

Funding Acknowledgement

Type of funding sources: None.

Microsatellite markers reveal polymorphisms at the 3′ untranslated region of the SLC11A1 gene in Zhongdian Yellow cattle (Bos taurus)

Solute carrier family 11-member A1 (SLC11A1) gene encodes natural macrophage resistance-associated protein which regulates activity of macrophages against intracellular pathogens. The objective of this study was to study the polymorphism in the microsatellites present at 3′ untranslated region (UTR) of the SLC11A1 gene in 113 Zhongdian Yellow cattle (Bos taurus). Using DNA bi-directional sequencing, we detected seven alleles (GT10–16) for the first microsatellite (MS1), five alleles (GT12–16) for MS2, and four alleles (GT4–7) for MS3. MS3 is studied for the first time and revealed four novel variants (alleles GT4–7). Alleles GT12 (45.1%), GT13 (59.3%), and GT5 (85.4%) were the most frequent alleles at MS1, MS2, and MS3, respectively, Genotypes G12/12, G13/13, and G5/5 had the highest frequency 0.239, 0.540, and 0.743 at MS1, MS2, and MS3, respectively. Haplotypic data revealed that GT12/GT13 was the most frequent haplotype observed followed by GT12/14 haplotype. Three nucleotide variations were observed in MS1 and MS2. Comparative analysis of GT12/GT12 and GT13/GT13 genotype with other bovine genotypes showed significant difference (P > 0.05). Our results suggest that the homozygous genotypes GT12/GT12 and GT13/GT13 in Zhongdian Yellow cattle might be related to disease resistance. The findings reported in this study would be helpful in cattle breeding programs.

Moving toward the elimination of cervical cancer: modelling the health and economic benefits of increasing uptake of human papillomavirus vaccines

Background

The human papillomavirus (hpv) is a common sexually transmitted infection and a primary cause of cervical cancer. The Government of Canada has set a target of reaching 90% hpv vaccine coverage among adolescents by 2025. Here, we examine hpv vaccine uptake in school-based immunization programs across Canada and explore how achieving the 90% target could affect the future incidence of cervical cancer, mortality, and health system expenditures in a cohort of Canadian women.

Methods

Data for hpv vaccine uptake in the most recent reported school year available in each jurisdiction were provided in 2017 by jurisdictional school-based immunization programs and were used to estimate a national weighted average of 67%. The OncoSim microsimulation model (version 2.5) was used to compare 3 different levels of hpv vaccine uptake (0%, 67%, 90%) on health and economic outcomes for a hypothetical cohort of all 5- to 10-year-old girls in Canada in 2015.

Results

Vaccine uptake for girls in school-based programs varied from 55.0% to 92.0% in the jurisdictions reviewed. The OncoSim model projects that increasing uptake to 90% from 67% would result in a 23% reduction in cervical cancer incidence rates (to 3.1 cases from 4.0 cases per 100,000, averaged across the lifetime of the cohort) and a 23% decline in the average annual mortality rate (to 1.0 deaths from 1.3 deaths per 100,000). Finally, the model projects that the health system will incur a cost of $9 million (1% increase) during the lifetime of the cohort if uptake is increased to 90% from 67%. Costs are discounted (1.5%) and expressed in 2016 Canadian dollars. Costs reflect the payer perspective.

Conclusions

Our model shows that increasing hpv vaccine uptake to 90% from current levels for girls in school-based immunization programs could result in substantial reductions in the future incidence and mortality rates for cervical cancer in Canada.

Cost-Effectiveness of Smoking Cessation Within a Lung Cancer Screening Program in Canada

Background: Demonstrated lung cancer mortality reductions through low-dose computed tomography (LDCT) has encouraged some jurisdictions to consider implementing organized LDCT screening. A retrospective analysis of former smokers in the National Lung Screening Trial (NLST) suggested that abstention from smoking coupled with low-dose computed tomography (LDCT) screening realized more mortality benefits than abstinence alone or LDCT alone. Aim: We evaluated the potential costs and cost-effectiveness of lung cancer screening with integrated smoking cessation using OncoSim-Lung (version 2.5), a microsimulation model led by the Canadian Partnership Against Cancer, with model development by Statistics Canada. Methods: We compared organized LDCT screening without smoking cessation to various plausible scenarios of screening with cessation. Assumptions included: annual screening of 55-74 year-old individuals with a 30-pack-yr history; a 42% participation rate reached over 10 years; cessation therapy (nicotine replacement therapy + varenicline + 12 weeks' counseling) at a cost of $490; and up to 10 cessation attempts, with a permanent quit rate of 5% per attempt. Cost-effectiveness was estimated with a lifetime horizon, health system perspective and 1.5% discount rate. Costs are in 2016 CAD. Results: OncoSim-Lung projected that LDCT screening integrated with cessation would cost approximately $76 million annually (undiscounted) from 2017 to 2036 in Canada. About 110 fewer lung cancer (LC) cases and 50 fewer LC deaths would occur annually, compared with screening without cessation. Additionally, many other smoking-related deaths would be prevented. Using a lifetime horizon, smoking cessation would cost $14,000/QALYs gained. In one-way sensitivity analysis, with a 72% participation rate there would be 260 fewer deaths, at $24,000/QALY. With a 10% quit rate, cost-effectiveness would improve to $6,000/QALY. A 50% increase in the cost of the cessation intervention would decrease cost-effectiveness to $22,000/QALY. Conclusion: Robust smoking cessation efforts within a LDCT screening program could save lives and be relatively cost-effective. Cancer control planners should consider integrating smoking cessation when implementing a lung cancer screening initiative.

Lung Cancer–Related Clinical and Economic Impacts of Achieving a 5% Smoking Prevalence Rate by 2035 in Canada

Background: Smoking is responsible for nearly 85% of lung cancer cases and 30% of all cancer-related deaths. Canada has set an ambitious target to reduce tobacco use to 5% by 2035 in alignment with a world-wide tobacco endgame initiative. Aim: We project the impact of achieving a national 5% smoking prevalence rate by 2035 on population-level lung cancer outcomes and costs. Methods: OncoSim-Lung (version 2.5), led by the Canadian Partnership Against Cancer with model development by Statistics Canada, is a microsimulation model that incorporates Canadian demographics, risk factors, registry data, resource utilization and other data to project clinical and economic impacts of cancer control measures. Smoking cessation parameters were modified to reduce the current average national smoking prevalence rate of 18% over time to 5% in 2035. Impacts were compared with those in a reference scenario, which maintained the current prevalence rate. Outputs of interest included lung cancer incidence, mortality, treatment costs, and quality-adjusted life-years (QALYs). Costs and QALYs are undiscounted and reported in 2016 CAD. Results: Achieving a 5% smoking rate by 2035 would result in a 2017-2035 cumulative total of 31,000 fewer lung cancer cases, 21,000 fewer lung cancer-related deaths, and 457,000 additional QALYs compared with projections based on a constant smoking prevalence rate of ∼20%. When stratified by sex, there would be 15,600 and 15,700 fewer lung cancer diagnoses and 11,000 and 10,000 fewer lung cancer-related deaths for males and females respectively. Furthermore, treatment-related costs would be reduced by $680 million dollars. On average there would be 4,500 fewer lung cancer cases, 3,500 fewer deaths, and $35 million in cost savings annually. If a 5% smoking rate is sustained until 2050, then there would be a 15% reduction in lung cancer cases and a 13% reduction in deaths from 2017-2050. Conclusion: Reducing Canada's smoking prevalence to 5% by 2035 could result in a significant reduction in lung cancer cases, deaths and treatment costs. Like Canada, other countries with relatively high smoking prevalence could use averted treatment costs to offset costs of aggressive smoking prevention and cessation programs or redirect them to other healthcare services.

Evaluating Clinical and Cost Impacts of Achieving 90% HPV Vaccination Rate Against Cervical Cancer in Canada Using the OncoSim Cancer Simulation Model

Background: Cervical cancer can be largely prevented through vaccination against the human papillomavirus (HPV). In Canada, HPV vaccination of school-aged girls started in 2008 and has reached an average rate of 67% across the country. However, this rate is below a current national target of 90%. Aim: We project the difference in lifetime clinical outcomes and health system costs of achieving a 90% HPV vaccination rate versus a 67% rate for girls vaccinated in 2015 using the OncoSim-Cervical model. Methods: The OncoSim-Cervical model (version 2.5) is a microsimulation model led by the Canadian Partnership Against Cancer, with model development by Statistics Canada, to evaluate the impacts of cervical cancer interventions in Canada. It has two parts, the first, the HPV Microsimulation Model, simulates the transmission of HPV between males and females including possible modulation by vaccination and herd immunity, and provides projections of HPV infection and prevalence for input to the cervical cancer natural history component in the second part. We simulated two cohorts of 5-10 year old girls in 2015; one receiving HPV vaccination at the rate of 67% and another at 90%. Their relative lifetime cervical cancer outcomes and costs were compared. Assumptions included: 100% efficacy of the HPV vaccine; triennial cytology screening between ages 21 and 65; 90% screening recruitment of age-eligible women with 80% rescreening; and a $500 cost for a 3-dose quadrivalent HPV vaccine regimen. Projected costs were undiscounted and are in 2016 CAD. Results: Compared with the 67%-vaccinated cohort, in the 90%-vaccinated cohort there was a lifetime reduction of 23% in cervical cancer incident cases and 21% in cervical cancer deaths. Lifetime cancer treatment costs decreased by $26 million (23%), and wart treatment costs and precervical cancer costs decreased by $3.2 million (15%) and $45 million (16%) respectively. Lifetime screening costs decreased by $47 million (2%). Conclusion: Achieving a nationally-set target of 90% HPV vaccination in Canadian girls would not only save more lives but would free up funds that could be redirected to other health system needs. Planners could aim for relatively high nation-wide rates of HPV vaccination coverage to enhance their cervical cancer control strategy.

Impact of Follow-Up Colonoscopy Quality on Canadian Colorectal Cancer Outcomes and Costs

Background: Most colorectal cancer (CRC) cases develop from precancerous polyps. Screening using fecal testing for occult blood, with follow-up diagnostic colonoscopy to remove polyps, can prevent invasive cancer from occurring. However, there is variation in the quality of colonoscopy, which may result in nonoptimal health outcomes. Aim: We evaluated the impact of follow-up colonoscopy quality on health outcomes, resource utilization and costs using the OncoSim-CRC microsimulation model (version 2.5). Methods: OncoSim is a microsimulation model led by the Canadian Partnership Against Cancer with model development by Statistics Canada. We compared results of high quality follow-up colonoscopy after positive fecal immunochemical testing (FIT) (colonoscopy sensitivity for cancer detection= 95%; compliance to follow-up colonoscopy = 85%) with that of reduced quality colonoscopy. Variations in colonoscopy performance were simulated through plausible overall effectiveness reduction (ER) and incomplete colonoscopy (IC). Screening system/patient follow-up deficiencies were simulated through poor compliance to diagnostic colonoscopy (PC). Modeling assumptions included: Biennial FIT screening of average-risk people aged 50-74; positive FIT followed by diagnostic colonoscopy; ER = 20% reduction in overall sensitivity; IC = zero sensitivity in proximal colon; PC = compliance reduction by 50%. Overall cost was calculated for 2017-2036 in undiscounted 2016 CAD, and included screening, treatment and end-of-life costs. Results: Compared with high quality colonoscopy follow-up, incomplete colonoscopy with poor compliance over 20 years led to as many as 12% new cases of CRC; 23% more CRC deaths; 89% more interval cancers; and 6% increased costs to the health care system, annually. Conclusion: Reduced colonoscopy quality can lead to considerable declines in the predicted effectiveness of screening and to increased costs to the healthcare system. Efforts to increase and maintain colonoscopy performance is a necessary component of CRC control planning.

The OncoSim Cancer Simulation Platform: A Tool to Project the Population Effects of Cancer Control Interventions in Canada

Background: Cancer control interventions exert their effects over multiple decades. To evaluate diverse and competing opportunities to reduce future cancer burden it is desirable to understand long-term effects prior to any new program implementation or significant change. Internationally, modeling is becoming an accepted source of planning information for decision-makers. Aim: We will describe the construction and use of the OncoSim microsimulation model, which was developed to evaluate cancer control strategies in Canada. Methods: OncoSim is a suite of models (cancers of the lung, colorectum, cervix and breast, plus a composite 32-cancer model) used to address key policy questions and support decision-making. It is led by the Canadian Partnership Against Cancer with model development by Statistics Canada. OncoSim incorporates risk factors, cancer natural history, screening, treatment, survival and end-of-life care. Wherever possible it is informed by Canadian data sources. Models are calibrated to reproduce a range of cancer-specific statistics, e.g., current and historical Canadian cancer-specific incidence and mortality, smoking patterns, and results of screening. The site-specific models have undergone further validation by replicating reported short-term effects of cancer prevention and screening interventions. Users may customize interventions through modifying input parameters. Outputs include incidence, mortality, costs, cost-effectiveness, and resource utilization. Users from the public sector have access at no cost to OncoSim and receive extensive support from a multidisciplinary technical team. The model is continually updated to incorporate emerging knowledge. Results: OncoSim has been used to support cancer control decision-making at the national and provincial/territorial levels. Applications include: national guidelines recommendations for colorectal and lung cancer screening; comparison of cytology vs. HPV based cervical cancer screening; and integration of smoking cessation into low-dose CT lung cancer screening. Conclusion: Validated simulation models such as OncoSim can be a versatile and efficient tool for cancer control planners to evaluate and prioritize cancer control strategies.

The OncoSim model: development and use for better decision-making in Canadian cancer control

The Canadian Partnership Against Cancer was created in 2007 by the federal government to accelerate cancer control across Canada. Its OncoSim microsimulation model platform, which consists of a suite of specific cancer models, was conceived as a tool to augment conventional resources for population-level policy- and decision-making. The Canadian Partnership Against Cancer manages the OncoSim program, with funding from Health Canada and model development by Statistics Canada. Microsimulation modelling allows for the detailed capture of population heterogeneity and health and demographic history over time. Extensive data from multiple Canadian sources were used as inputs or to validate the model. OncoSim has been validated through expert consultation; assessments of face validity, internal validity, and external validity; and model fit against observed data. The platform comprises three in-depth cancer models (lung, colorectal, cervical), with another in-depth model (breast) and a generalized model (25 cancers) being in development. Unique among models of its class, OncoSim is available online for public sector use free of charge. Users can customize input values and output display, and extensive user support is provided. OncoSim has been used to support decision-making at the national and jurisdictional levels. Although simulation studies are generally not included in hierarchies of evidence, they are integral to informing cancer control policy when clinical studies are not feasible. OncoSim can evaluate complex intervention scenarios for multiple cancers. Canadian decision-makers thus have a powerful tool to assess the costs, benefits, cost-effectiveness, and budgetary effects of cancer control interventions when faced with difficult choices for improvements in population health and resource allocation.

Implementing low-dose computed tomography screening for lung cancer in Canada: implications of alternative at-risk populations, screening frequency, and duration

BACKGROUND

Low-dose computed tomography (ldct) screening has been shown to reduce mortality from lung cancer; however, the optimal screening duration and "at risk" population are not known.

METHODS

The Cancer Risk Management Model developed by Statistics Canada for the Canadian Partnership Against Cancer includes a lung screening module based on data from the U.S. National Lung Screening Trial (nlst). The base-case scenario reproduces nlst outcomes with high fidelity. The impact in Canada of annual screening on the number of incident cases and life-years gained, with a wider range of age and smoking history eligibility criteria and varied participation rates, was modelled to show the magnitude of clinical benefit nationally and by province. Life-years gained, costs (discounted and undiscounted), and resource requirements were also estimated.

RESULTS

In 2014, 1.4 million Canadians were eligible for screening according to nlst criteria. Over 10 years, screening would detect 12,500 more lung cancers than the expected 268,300 and would gain 9200 life-years. The computed tomography imaging requirement of 24,000-30,000 at program initiation would rise to between 87,000 and 113,000 by the 5th year of an annual nlst-like screening program. Costs would increase from approximately $75 million to $128 million at 10 years, and the cumulative cost nationally over 10 years would approach $1 billion, partially offset by a reduction in the costs of managing advanced lung cancer.

CONCLUSIONS

Modelling various ways in which ldct might be implemented provides decision-makers with estimates of the effect on clinical benefit and on resource needs that clinical trial results are unable to provide.

Using the Cancer Risk Management Model to evaluate the health and economic impacts of cytology compared with human papillomavirus DNA testing for primary cervical cancer screening in Canada

BACKGROUND

In Canada, discussion about changing from cytology to human papillomavirus (hpv) dna testing for primary screening in cervical cancer is ongoing. However, the Canadian Task Force on Preventive Health Care has not yet made a recommendation, concluding that the evidence is insufficient.

METHODS

We used the cervical cancer and hpv transmission models of the Cancer Risk Management Model to study the health and economic outcomes of primary cytology compared with hpv dna testing in 14 screening scenarios with varying screening modalities and intervals. Projected cervical cancer cases, deaths, colposcopies, screens, costs, and incremental cost-effectiveness were evaluated. We performed sensitivity analyses for hpv dna test costs.

RESULTS

Compared with triennial cytology from age 25, 5-yearly hpv dna screening alone from age 30 resulted in equivalent incident cases and deaths, but 55% (82,000) fewer colposcopies and 43% (1,195,000) fewer screens. At hpv dna screening intervals of 3 years, whether alone or in an age-based sequence with cytology, screening costs are greater, but at intervals of more than 5 years, they are lower. Scenarios on the cost-effectiveness frontier were hpv dna testing alone every 10, 7.5, 5, or 3 years, and triennial cytology starting at age 21 or 25 when combined with hpv dna testing every 3 years.

CONCLUSIONS

Changing from cytology to hpv dna testing as the primary screening test for cervical cancer would be an acceptable strategy in Canada with respect to incidence, mortality, screening and diagnostic test volumes.

Systematic review and meta-analysis of the accuracy of MRI and endorectal ultrasound in the restaging and response assessment of rectal cancer following neoadjuvant therapy

AIM

Restaging imaging by MRI or endorectal ultrasound (ERUS) following neoadjuvant chemoradiotherapy is not routinely performed, but the assessment of response is becoming increasingly important to facilitate individualization of management.

METHOD

A search of the MEDLINE and Scopus databases was performed for studies that evaluated the accuracy of restaging of rectal cancer following neoadjuvant chemoradiotherapy with MRI or ERUS against the histopathological outcome. A systematic review of selected studies was performed. The methodological quality of studies that qualified for meta-analysis was critically assessed to identify studies suitable for inclusion in the meta-analysis.

RESULTS

Sixty-three articles were included in the systematic review. Twelve restaging MRI studies and 18 restaging ERUS studies were eligible for meta-analysis of T-stage restaging accuracy. Overall, ERUS T-stage restaging accuracy (mean [95% CI]: 65% [56-72%]) was nonsignificantly higher than MRI T-stage accuracy (52% [44-59%]). Restaging MRI is accurate at excluding circumferential resection margin involvement. Restaging MRI and ERUS were equivalent for prediction of nodal status: the accuracy of both investigations was 72% with over-staging and under-staging occurring in 10-15%.

CONCLUSION

The heterogeneity amongst restaging studies is high, limiting conclusive findings regarding their accuracies. The accuracy of restaging imaging is different for different pathological T stages and highest for T3 tumours. Morphological assessment of T- or N-stage by MRI or ERUS is currently not accurate or consistent enough for clinical application. Restaging MRI appears to have a role in excluding circumferential resection margin involvement.

Prospective Study of Early MRI Appearances following Flow-Diverting Stent Placement for Intracranial Aneurysms

BACKGROUND AND PURPOSE

MR imaging findings of aneurysm enlargement, aneurysm wall enhancement, perianeurysmal edema, and embolic phenomena following deployment of flow-diverting stents may be relevant to those patients who subsequently experience procedure-related intracranial hemorrhage. We sought to document the routine early postoperative MR imaging findings following flow-diverting stent insertion.

MATERIALS AND METHODS

Patients requiring flow-diverting stent placement for treatment or retreatment of cerebral aneurysms were prospectively included in the study during a 26-month period. Early postprocedural MR imaging studies were obtained and compared with preoperative imaging. Patient clinical outcome data were also collected.

RESULTS

There were 34 stent-placement procedures during the study period. Aneurysm mural enhancement and mild new perianeurysmal edema were present in 50% and 14%, respectively. Any DWI lesion was present in 57% of cases. New or possibly new foci of susceptibility effect were found ipsilateral to the stent and not associated with diffusion restriction in 66% of cases. There were 2 cases (6%) of parenchymal hemorrhage and 2 major clinical complications (6%) causing permanent morbidity.

CONCLUSIONS

Asymptomatic aneurysm mural enhancement is frequently seen following flow-diverting stent placement and should not necessarily be interpreted as a sign of impending aneurysm rupture. This finding often persists despite complete aneurysm occlusion. New small brain parenchymal susceptibility foci following stent placement have not previously been reported, to our knowledge, but were common in our series.

Primary Sjögren's Syndrome Presenting as Flaccid Quadriparesis

Primary Sjögren's syndrome is an autoimmune disease presenting classically as keratoconjunctivitis sicca. Renal involvement in Sjögrens's syndrome is less common, and the initial presentation with renal complications without any sicca symptoms is extremely rare. The renal involvement may present with symptoms arising from interstitial nephritis, mainly distal renal tubular acidosis.

Primary cell and micromass culture in assessing developmental toxicity

Under the European Commission's New Chemical Policy both currently used and new chemicals should be tested for their toxicities in several areas, one of which was reproductive/developmental toxicity. Thousands of chemicals will need testing which will require a large number of laboratory animals. In vitro systems (as pre-screens or as validated alternatives) appear to be useful tools to reduce the number of whole animals used or refine procedures and hence decrease the cost for the chemical industry. Validated in vitro systems exist for developmental toxicity/embryotoxicity testing. Indeed, three assays have recently been validated: the whole embryo culture (WEC), the rat limb bud micromass (MM), and the embryonic stem cell test (EST). In this article, the use of primary embryonic cell culture, and in particular micromass culture, including a relatively novel chick heart micromass (MM) culture system has been described and compared to the validated D3 mouse embryonic stem cell (ESC) test.

Knowledge, attitudes and practices of barbers about hepatitis B and C transmission in Hyderabad, Pakistan

Hepatitis B and C virus (HBV/HCV) infections are serious global health problems. Shaving by barbers has been identified as the key risk factor for spread of HBV. We conducted a cross-sectional survey of barbers in Hyderabad city, Pakistan in 2007 to establish their knowledge and attitudes to the risk of HBV and HCV transmission and their working patterns. Observations showed that 96.2% washed razors with antiseptic after each client and 95.7% used a new blade with new clients. However, knowledge about the diseases and modes of transmission were poor and only 36.6% knew that hepatitis can be transmitted via shaving instruments. Only 3.2% of 186 barbers were vaccinated against HBV. Strategies are needed for raising awareness and regulations of barbers' practices.

An evaluation of topical and local anesthesia in phacoemulsification

OBJECTIVE

To assess the comparative efficacy of topical and local anesthesia in phacoemulsification.

MATERIAL AND METHODS

The medical records of 186 men and women between the ages of 45-85 years, who underwent elective cataract surgery by phacoemulsification technique, under the care of one surgeon, over a period of one year, from March 1999-March 2000 were reviewed.

RESULTS

Of 186 patients who underwent small incision, self-healing phacoemulsification cataract surgery, 124 received topical and 62 local anesthesia. The most common cataract types were nuclear sclerosis. The duration of surgery with topical anesthesia was shorter. Sutures and eye padding were more frequently applied for procedures done under local anesthesia. Uncorrected visual acuity in the first post-op week was between 20/20-20/50 for 53.6% of the cases done under topical compared to 30.9% in local anesthesia. A similar trend was noted in the visual acuity one month post operatively.

CONCLUSION

The uncorrected visual acuity improves faster and the duration of surgery is shorter when topical anesthesia is used.

Effects of high sugar diets on renal fluid, electrolyte and mineral handling in rats: relationship to blood pressure

OBJECTIVE

We examined whether sugar-induced systolic blood pressure (SBP) elevations in rats may develop, in part, through a mechanism common to salt-induced hypertension, i.e., renal retention of water and salt.

DESIGN

Spontaneously hypertensive rats (SHR) ate four diets: two high (> 50% of calories) and two low (< 12% of calories) in sugar (sucrose). SBP, various urinary parameters, and the renal angiotensin and prostaglandin systems were assessed.

RESULTS

SHR consuming diets high in sugar showed significantly decreased urinary volume and excretion of electrolytes, which coincided with increasing SBP. When low sugar diets replaced high sugar diets, SBP and urinary parameters rapidly returned to baseline. SHR received captopril while consuming high sugar diets, and both SBP and urinary parameters assumed baseline values, comparable to ones seen in SHR consuming low sugar diets. A direct angiotensin II receptor antagonist (DuPont 753) did not influence SBP. However, we found decreased PGE2 excretion in SHR consuming excess sugar.

CONCLUSIONS

Salt and water retention occur early during sugar-induced hypertension due to reduced renal excretion, consistent with some part in the pathogenesis. The effects of high sugar diets on SBP were not due to angiotensin II inhibition, however, decreased availability of vasodilatory prostaglandins may play a role in the renal events and sugar-induced hypertension in SHR.

Rabbit and human renotropin are not epidermal growth factor

Sera obtained from rabbits and humans after unilateral nephrectomy (uni sera) compared with sera obtained preoperatively (control sera) significantly stimulate 3H-thymidine incorporation into the DNA of cultured renal tissue from the respective species. In contrast, rabbit liver cells in culture are not stimulated by the uni sera compared with control sera obtained from rabbits. Mouse epidermal growth factor (EGF) added to tissue cultures significantly stimulates both kidney and liver cells of rabbits and kidney cells of humans. Antiserum against EGF overcomes, at least to some extent, the enhancing effect of EGF under all circumstances, but does not influence the stimulatory ability of uni serum obtained from rabbit and human kidney cells from the respective species. In addition, the activity of EGF was not different in the presence of uni and control sera. This study corroborates the presence of renotropic activity in the sera of rabbits and humans after removal of functioning renal mass and shows that this activity is not derived from EGF, nor does it work by potentiating some aspect of the EGF system.

Important aspects concerning evaluation of renal function and blood pressure. Kinins, prostaglandins, lead

The kallikrein-kinin and prostaglandin-thromboxane-leukotriene systems and the body lead burden all influence renal function and systemic blood pressure to some extent. Because these systems may become generally accepted as more important in assessing renal function and blood pressure in the future, a brief overview of each has been given.

Antibody reactivity with HBLV (HHV-6) in U.S. populations

500 sera representing healthy blood donors and a random representation of the U.S. population collected 10 years ago were screened by ELISA for antibody reactivity with purified, disrupted HBLV virions. In each group, the ELISA results were normally distributed with no evidence of bimodality. All sera were subsequently retested after preincubation of each with well-characterized preparations of disrupted HSB-2 cells or HBLV-infected HSB-2 cells. Sera showing significant levels of HBLV-specific neutralization (50% or more) were found in Minneapolis, Kansas City, and in a random population survey (81, 88 and 97% of donors, respectively). Mean ELISA test values were the same for all groups and for males and females within the same group. Sera from these normal donors reacted preferentially with viral antigens of 120 and 58 kDa by Western blot. In a hospital-based prevalence study, frequent IgM and IgG seroconversions were apparent among infants less than 1 year old, and mean ELISA test values reached the adult level before school age. Antigen preparations used in blocking experiments showed no competitive cross-reactivity with antisera against EBV, CMV, HSV, VZV, HIV, or adenovirus type 2 at levels which reduced antibody binding to HBLV by more than 90%. Antibody cross-reactivities towards HBLV and other human herpesviruses were assessed by cross-correlation of viral antibody titers against all of the viruses and by cross-absorptions of antisera against the other viruses with HBLV. In these experiments no antibody cross-reactivity between HBLV and other human herpesviruses were detected. The significance of these findings with respect to health/disease status is presently unknown. Further seroepidemiologic studies of quantitative levels of HBLV antibody reactivity to measure the age of primary infection and progressive changes in healthy and selected disease populations are needed to determine the risk of disease associated with HBLV infection.

Human B-lymphotropic virus (human herpesvirus-6)

Human B-lymphotropic virus (HBLV), also known as human herpesvirus-6 (HHV-6) was first isolated in 1986 from AIDS patients and patients with other lymphoproliferative disorders. HBLV is distinct from known human herpesviruses, biologically, immunologically and by molecular analysis. HBLV can infect and replicate in fresh and established lines of hemopoietic cells and cells of neural origin, suggesting wide tropism. The prevalence of HBLV antibody in the normal population was 26% though clear differences between different populations were observed. The prevalence of HBLV antibody an elevated antibody titer was higher in sera from certain malignancies, Sjögren's syndrome and sarcoidosis. Antibody to HBLV was also elevated in AIDS patients and patients with chronic fatigue syndrome. HBLV-DNA was detected in some B-cell lymphomas. The broad in vitro tropism, combined with immunological and molecular evidence of HBLV infection in individuals raise the question of the pathogenicity of this virus in some diseases. Because in vitro co-infection of CD4 cells by HBLV and HIV leads to enhanced degeneration, this raises the possibility that infection in AIDS patients by both viruses can aggravate the HIV-induced immunodeficiency. Specific reagents and immunological and molecular assays are currently being investigated, which will aid in virus detection in cells from patients, and in elucidating the possible pathogenesis of HBLV.

Molecular studies of HHV-6

Methods for the purification of enveloped HHV-6 virions and the viral DNA are presented. The viral genome is estimated to be 170,000 base pairs in size and does not appear to contain inversions due to absence of submolar bands by restriction enzyme analyses. The genomes of two independent HHV-6 isolates, HHV-6GS and HHV-6Z29, showed restriction enzyme site pleomorphism. Large scale purification of enveloped HHV-6 was achieved by continuous flow centrifugation utilizing sucrose gradients, DNAse 1 treatment and banding on 10-30% Dextran T10 gradients. The viral proteins were visualized on high resolution two dimensional polyacrylamide gels and the proteins recognized by serum antibody from patient GS were detected by HR2D Western blot analysis and radioimmunoprecipitation assay. The major antigenic proteins were 200, 120, 80, 72, 30 and 19 kDa.