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Abstract Background In most recent large efficacy trials of barrier contraceptive methods, a high proportion of participants withdrew before the intended end of follow-up. The objective of this analysis was to explore characteristics of participants who failed to complete seven months of planned participation in a trial of spermicide efficacy. Methods Trial participants were expected to use the assigned spermicide for contraception for 7 months or until pregnancy occurred. In bivariable and multivariable analyses, we assessed the associations between failure to complete the trial and 17 pre-specified baseline characteristics. In addition, among women who participated for at least 6 weeks, we evaluated the relationships between failure to complete, various features of their first 6 weeks of experience with the spermicide, and characteristics of the study centers and population. Results Of the 1514 participants in this analysis, 635 (42%) failed to complete the study for reasons other than pregnancy. Women were significantly less likely to complete if they were younger or unmarried, had intercourse at least 8 times per month, or were enrolled at a university center or at a center that enrolled fewer than 4 participants per month. Noncompliance with study procedures in the first 6 weeks was also associated with subsequent early withdrawal, but dissatisfaction with the spermicide was not. However, many participants without these risk factors withdrew early. Conclusions Failure to complete is a major problem in barrier method trials that seriously compromises the interpretation of results. Targeting retention efforts at women at high risk for early withdrawal is not likely to address the problem sufficiently.

Background: An estimated 43% of children under age 5 in low- and middle-income countries (LMICs) experience compromised development due to poverty, poor nutrition, and inadequate psychosocial stimulation. Numerous early childhood development (ECD) parenting interventions have been shown to be effective at improving ECD outcomes, at least in the short-term, but they are (a) still too expensive to implement at scale in low-resource and rural settings, and (b) their early impacts tend to fade over time. New approaches to deliver effective ECD parenting interventions that are low-cost, scalable, and sustainable are sorely needed., Methods: Our study will experimentally test a traditional in-person group-based delivery model for an evidence-based ECD parenting intervention against a hybrid-delivery model that increasingly substitutes in-person meetings with remote (mHealth) delivery via smartphones, featuring audiovisual content and WhatsApp social interactions and learning. We will assess the relative effectiveness and cost of this hybrid-delivery model compared to in-person delivery and will extend the interventions over two years to increase their ability to sustain changes in parenting behaviors and ECD outcomes longer-term. Our evaluation design is a cluster Randomized Controlled Trial (cRCT) across 90 villages and approximately 1200 households. Midline and endline surveys collected 12 and 24 months after the start of the interventions, respectively, will examine short- and sustained two-year intention-to-treat impacts on primary outcomes. We will also examine the mediating pathways using mediation analysis. We hypothesize that a hybrid-delivery ECD intervention will be lower in cost, but remote interactions among participants may be an inferior substitute for in-person visits, leaving open the question of the most cost-effective program., Discussion: Our goal is to determine the best model to maximize the intervention's reach and sustained impacts to improve child outcomes. By integrating delivery into the ongoing operations of local Community Health Promoters (CHPs) within Kenya's rural health care system, and utilizing new low-cost technology, our project has the potential to make important contributions towards discovering potentially scalable, sustainable solutions for resource-limited settings., Trial Registration: NCT06140017 (02/08/2024) AEARCTR0012704., (© 2024. The Author(s).)

Campylobacteriosis, primarily caused by Campylobacter jejuni and C. coli, is the main bacterial zoonosis worldwide. While poultry is recognized as the main reservoir, bovines are considered another important reservoir for Campylobacter spp. found in human infections. In contrast to chicken, retail beef is seldom contaminated by Campylobacter species. However, beef liver is recognized to be frequently contaminated and has been linked to human infections via epidemiological investigations. Our aims were to evaluate the prevalence of Campylobacter spp. inside and on the surface of beef liver pieces at retail in Finland and to analyse the population in more detail using whole genome sequencing (WGS) to assess the public health relevance. A total of 90 retail beef livers were studied using both enrichment of the external peptone-saline rinse of the liver piece and direct culture from the inside after surface sterilization. Furthermore, 46 of the livers were also studied using direct culture of retail beef liver juice collected from the bottom of the consumer package to estimate the concentration of Campylobacter species. Overall, 44 (49 %) of the samples were positive for Campylobacter species, C. jejuni, C. fetus and C. lari being identified in 42 %, 8.9 % and 1.1 % of the samples, respectively. Direct culture of retail liver juice was a sensitive and convenient method for Campylobacter spp. detection, resulting in 48 % prevalence and a mean concentration of 49 cfu/ml (maximum 335 cfu/ml). Two samples (2.2 %), containing large hepatic ducts, were positive for C. jejuni internally, representing multilocus sequence typing (MLST) sequence type ST-19 and ST-21. WGS, core genome phylogeny and core genome MLST revealed that in most cases only one clearly distinct clone of clinically relevant C. jejuni or C. fetus was isolated from a single lot of samples. However, in some cases several distinct clones were identified simultaneously even from a single liver piece. In epidemiological investigations, it is thus highly advisable to genotype multiple isolates to capture the whole diversity of Campylobacter spp. from suspected food sources. Good kitchen hygiene, avoidance of cross-contamination and thorough cooking are important for limiting the transmission of campylobacteriosis., Competing Interests: Declaration of competing interest None., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Recently, it has been shown and validated that presence and severity of emphysema on computed tomography could be estimated by a novel spirometry based index, the emphysema severity index (ESI). However, the clinical relevance of the index has not been established. We conducted cox-regression analyses with adjustment for age, smoking, sex, forced expiratory volume in 1 s (FEV 1 ) and forced vital capacity (FVC) to study whether ESI was associated with all-cause, respiratory and non-respiratory 10-year mortality. Study population was all participants with acceptable spirometry from the Gott Åldrande i Skåne study, a Swedish general population aged 65-102 years old. ESI is expressed as a continuous numeric parameter on a scale ranging from 0 to 10. Out of the 4453 participants in the main study, 3974 was included in the final analysis. Higher age, higher ESI, lower FEV 1 and male sex increased hazard of respiratory death. ESI was significantly correlated to respiratory death but not non-respiratory death, while high age, male sex and low FEV 1 was associated with non-respiratory as well as respiratory death. Current smoking habits increased the hazard of respiratory death but did not reach significance (p 0.066) One unit increase in ESI increased hazard of all-cause death by 20% (p 0.0002) and hazard of respiratory death by 57% (p < 0.0001). The ESI is a novel clinical marker of emphysema severity that is associated with respiratory death specifically. Since it can be derived from standard spirometry there are potential benefits for clinical practice in terms of more individualised prognosis and treatment alternatives., Competing Interests: Declaration of competing interest Dr. Occhipinti reports grants from Fondazione Menarini, personal fees from Novartis, outside the submitted work; Dr. Wollmer reports grants from Swedish Heart and Lung Foundation, grants from Lund University, grants from Skåne Region, during the conduct of the study; personal fees from Chiesi Pharma, outside the submitted work; In addition, Dr. Wollmer has a patent Device and method for pulmonary function measurement issued.. Dr. Luoto reports grants from Skåne County, during the conduct of the study., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

We evaluated whether antenatal supply-side and demand-side interventions in 10 public health care facilities (HCFs) increased the percentage of women who had four or more antenatal care (ANC4+) visits and HCF deliveries from baseline to follow-up compared with women in 10 public control HCFs in Kenya. We compared maternal registry data during baseline and follow-up periods between public intervention and public control HCFs; we added seven private intervention HCFs and five private control HCFs to evaluate an unanticipated pilot insurance program that enabled women to use private intervention HCFs. From baseline to follow-up, ANC4+ visits and HCF deliveries in public intervention HCFs were 1.64 and 1.19 times greater, respectively, than in public control HCFs. Health care facility deliveries were 1.5 times higher in private intervention HCFs than public intervention HCFs. Results suggested that the combined antenatal and insurance interventions motivated increased ANC4+ visits and HCF deliveries. Women appeared to prefer private HCFs for delivery.

Background: Antenatal care (ANC) and delivery by skilled providers have been well recognized as effective strategies to prevent maternal and neonatal mortality. ANC and delivery services at health facilities, however, have been underutilized in Kenya. One potential strategy to increase the demand for ANC services is to provide health interventions as incentives for pregnant women. In 2013, an integrated ANC program was implemented in western Kenya to promote ANC visits by addressing both supply- and demand-side factors. Supply-side interventions included nurse training and supplies for obstetric emergencies and neonatal resuscitation. Demand-side interventions included SMS text messages with appointment reminders and educational contents, group education sessions, and vouchers to purchase health products., Methods: To explore pregnant mothers' experiences with the intervention, ANC visits, and delivery, we conducted focus group discussions (FGDs) at pre- and post-intervention. A total of 19 FGDs were held with pregnant mothers, nurses, and community health workers (CHWs) during the two assessment periods. We performed thematic analyses to highlight study participants' perceptions and experiences., Results: FGD data revealed that pregnant women perceived the risks of home-based delivery, recognized the benefits of facility-based delivery, and were motivated by the incentives to seek care despite barriers to care that included poverty, lack of transport, and poor treatment by nurses. Nurses also perceived the value of incentives to attract women to care but described obstacles to providing health care such as overwork, low pay, inadequate supplies and equipment, and insufficient staff. CHWs identified the utility and limitations of text messages for health education., Conclusions: Future interventions should ensure that adequate workforce, training, and supplies are in place to respond to increased demand for maternal and child health services stimulated by incentive programs.

Improving access to safe and affordable sanitation facilities is a global health priority that is essential for meeting the United Nation's Sustainable Development Goals. To promote the use of improved sanitation in rural and low-income settings, plastic latrine slabs provide a simple option for upgrading traditional pit latrines. The International Finance Corporation/World Bank Selling Sanitation program estimated that plastic slabs would have a 34% annual growth, with a market size of US$2.53 million in Kenya by 2017. In this study, we examined the commercial viability of these plastic latrine slabs in rural Kenya by evaluating a financing and distribution model intervention, documenting household slab sales to date, and assessing consumer exposure and perceptions. We also determined household willingness to pay through a real-money auction with 322 households. We found that no households in our study area had purchased the plastic slabs. The primary barriers to slab sales were limited marketing activities and low demand compared with the sales price: households were willing to pay an average of US$5 compared with a market price of US$16. Therefore, current household demand for the plastic latrine slabs in rural Kenya is too low to support commercial distribution. Further efforts are required to align the price of plastic latrine slabs with consumer demand in this setting, such as additional demand creation, product financing, and public sector investment.

Data on longitudinal lung function change in the elderly are scarce. Uncertainty remains about whether to use absolute or relative change and how it relates to subject demographics.We studied absolute and relative forced expiratory volume in 1 s (FEV 1 ) and forced vital capacity (FVC) change in a population-based geriatric sample using a repeated measurements model adjusted for age, sex, smoking habits, heart failure, hypertension, diabetes, coronary heart disease, educational level, occupation, alcohol consumption, C-reactive protein (CRP) and body mass index. 3736 participants aged 60-102 years completed between one and five spirometries during 13.5 years of follow-up. Lung volumes, FEV 1 quotient (Q) and Global Lung Initiative (GLI)-2012 and National Health and Nutrition Examination Survey (NHANES) III z-scores were presented from 6932 spirometries.Adjusted absolute change per year (95% CI) was -51.7 (-63.7--39.9) mL for FEV 1 and -56.2 (-73.6--38.8) mL for FVC. Adjusted relative change per year was -2.97 (-3.53--2.40)% for FEV 1 and -2.46 (-3.07--1.85)% for FVC. Risk factors for increased relative FVC and FEV 1 decline were female sex, higher age, current smoking habits, elevated CRP (nonsignificant for FEV 1 , p=0.057) and low educational level. For increased absolute decline the risk factors were male sex and being a current smoker for FEV 1 and low education for FVC.Relative but not absolute change correlated significantly with clinically relevant markers of functional status and may be superior to absolute change in risk factor analysis. Cross-sectional reduction in terms of FEV 1 Q was ∼1 unit per 10 years for both sexes. Proportions of subjects with results below lower limit of normal using NHANES III were close to anticipated, but were two to four times higher than expected using GLI-2012., Competing Interests: Conflict of interest: J. Luoto reports grants from Skåne County, during the conduct of the study. Conflict of interest: M. Pihlsgård has nothing to disclose. Conflict of interest: P. Wollmer reports grants from Swedish Heart and Lung Foundation, during the conduct of the study; personal fees for lecturing from AstraZeneca AB, outside the submitted work; in addition, P. Wollmer has a patent device and method for pulmonary function measurement pending. Conflict of interest: S. Elmståhl reports grants from Swedish Research Council (grant numbers 521-2013-8604 and 2017-01613), during the conduct of the study., (Copyright ©ERS 2019.)

Purpose: To comprehensively measure the impacts of cataract surgery on patients' activities and mental and physical health, caregivers' well-being, and household incomes in a resource-poor setting Methods: One thousand two hundred thirty-four bilaterally blind older adults in Amhara region, Ethiopia, were interviewed at baseline and 1030 (83%) re-interviewed at follow-up 1 year later. Six hundred ninety three (45%) at baseline were diagnosed with cataracts and offered free surgery, of which 484 (73%) were operated. Difference-in-difference was used to estimate impacts of surgery, using surgery-ineligible, mostly non-cataract blind as controls., Results: For patients, surgery resulted in a 0.31 standard deviation increase in an index of social participation (p < 0.001), a 30% proportional increase in ability to perform activities of daily living (p < 0.001), and a 17% proportional reduction in Center for Epidemiologic Studies Depression Scale (CES-D) depression score (p < 0.001). A small (6%) increase in work participation occurred among men (p = 0.093) in this elderly sample. No change occurred in individual or household food insecurity, household consumption, or assets. Caregivers' mental health improved slightly (7.3% proportional reduction in CES-D; p = 0.024). Estimates show no change in caregiver work participation or social participation; however, subjective responses regarding changes from surgery suggest that reduced caregiving time was an important benefit to households., Conclusion: Cataract surgery significantly improved the vision as well as mental health, social engagement, and physical functioning of older adults. However, increases in work participation were very limited, likely reflecting the advanced age of the patients (mean = 76 years); in addition, possibly, to cumulative impacts of blindness on ability to work or on household assets. Earlier surgery may lead to larger economic effects.

Objectives: To assess the effectiveness of Short Message Service (SMS) reminder messages on antiretroviral and cotrimoxazole prophylaxis adherence among HIV-positive youths as well as the relative effectiveness of SMS with and without a response option., Methods: Eligible HIV-positive patients aged 15 to 22 years at 2 HIV clinics in Kampala, Uganda, participated in a year-long parallel individual-randomized controlled trial and were assigned in a 1-to-1-to-1 ratio to a weekly SMS message group, weekly SMS message with response option group, or a usual-care control group., Results: We enrolled 332 participants. Electronically measured mean adherence was 67% in the control group, 64% in the 1-way SMS group (95% confidence interval [CI] = 0.77, 1.14), and 61% in the 2-way SMS group (95% CI = 0.75, 1.12) in an intent-to-treat analysis. Results for secondary outcomes and complete-case analysis were similarly statistically insignificant across groups., Conclusions: Despite previous evidence that interventions using SMS reminders can promote antiretroviral therapy adherence, this study shows that they are not always effective in achieving behavior change. More research is needed to find out for whom, and under what conditions, they can be beneficial., Trial Registration: ClinicalTrials.gov identifier: NCT00830622.

Purpose: To examine the relationships between blindness, the intervention of cataract surgery and all-cause mortality in a rural Ethiopian population., Design: Population-based, interventional prospective study., Methods: Community-based detection methods identified blind Ethiopian persons from two selected kebeles in Amhara region, Ethiopia. Data from 1201 blind patients were collected-628 cataract-blind and 573 blind from other conditions. Free cataract surgery was provided for consenting, cataract-blind patients. Follow-up surveys were conducted after 12 months (±1 month)-the main outcome measure for this report is all-cause mortality at 1 year., Results: During the follow-up period, 110 persons died from the selected population (mortality 9.2%), which consisted of those cataract-blind patients who received cataract surgery (N=461), cataract-blind patients who did not receive surgery (N=167) and all non-cataract-blind patients (N=573). Of the 461 patients who received cataract surgery, 44 patients died (9.5%). Of the 740 patients who did not receive surgery, 66 died (8.9%)-28 patients from the cohort of cataract-blind patients who did not receive surgery (16.8%) and 38 patients from the cohort of non-cataract blind (6.6%). Subgroup analysis revealed significantly increased odds of mortality for cataract-blind patients over 75 years of age who did not receive surgery and for unmarried patients of all age groups., Conclusions: In this population, mortality risk was significantly elevated for older cataract-blind patients when compared with non-cataract-blind patients-an elevation of risk that was not noted in an age-matched cohort of cataract-blind patients who underwent cataract surgery as early as 1-year follow-up., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Background: There is an increasing push for 'evidence-based' decision making in global health policy circles. However, at present there are no agreed upon standards or guidelines for how to evaluate evidence in global health. Recent evaluations of existing evidence frameworks that could serve such a purpose have identified details of program context and project implementation as missing components needed to inform policy. We performed a pilot study to assess the current state of reporting of context and implementation in studies of global health interventions., Methods: We identified three existing criteria sets for implementation reporting and selected from them 10 criteria potentially relevant to the needs of policy makers in global health contexts. We applied these 10 criteria to 15 articles included in the evidence base for three global health interventions chosen to represent a diverse set of advocated global health programs or interventions: household water chlorination, prevention of mother-to-child transmission of HIV, and lay community health workers to reduce child mortality. We used a good-fair-poor/none scale for the ratings., Results: The proportion of criteria for which reporting was poor/none ranged from 11% to 54% with an average of 30%. Eight articles had 'good' or 'fair' documentation for greater than 75% of criteria, while five articles had 'poor or none' documentation for 50% of criteria or more. Examples of good reporting were identified., Conclusions: Reporting of context and implementation information in studies of global health interventions is mostly fair or poor, and highly variable. The idiosyncratic variability in reporting indicates that global health investigators need more guidance about what aspects of context and implementation to measure and how to report them. This lack of context and implementation information is a major gap in the evidence needed by global health policy makers to reach decisions.

Low-cost point-of-use (POU) safe water products have the potential to reduce waterborne illness, but adoption by the global poor remains low. We performed an eight-month randomized trial of four low-cost household water treatment products in Dhaka, Bangladesh. Intervention households (n = 600) received repeated educational messages about the importance of drinking safe water along with consecutive two-month free trials with each of four POU products in random order. Households randomly assigned to the control group (n = 200) did not receive free products or repeated educational messages. Households' willingness to pay for these products was quite low on average (as measured by bids in an incentive-compatible real-money auction), although a modest share was willing to pay the actual or expected retail price for low-cost chlorine-based products. Furthermore, contrary to our hypotheses that both one's own personal experience and the influence of one's peers would increase consumers' willingness to pay, direct experience significantly decreased mean bids by 18-55% for three of the four products and had no discernible effect on the fourth. Neighbor experience also did not increase bids. Widespread dissemination of safe water products is unlikely until we better understand the preferences and aspirations of these at-risk populations.

Background: There is evidence that household point-of-use (POU) water treatment products can reduce the enormous burden of water-borne illness. Nevertheless, adoption among the global poor is very low, and little evidence exists on why., Methods: We gave 600 households in poor communities in Dhaka, Bangladesh randomly-ordered two-month free trials of four water treatment products: dilute liquid chlorine (sodium hypochlorite solution, marketed locally as Water Guard), sodium dichloroisocyanurate tablets (branded as Aquatabs), a combined flocculant-disinfectant powdered mixture (the PUR Purifier of Water), and a silver-coated ceramic siphon filter. Consumers also received education on the dangers of untreated drinking water. We measured which products consumers used with self-reports, observation (for the filter), and chlorine tests (for the other products). We also measured drinking water's contamination with E. coli (compared to 200 control households)., Findings: Households reported highest usage of the filter, although no product had even 30% usage. E. coli concentrations in stored drinking water were generally lowest when households had Water Guard. Households that self-reported product usage had large reductions in E. coli concentrations with any product as compared to controls., Conclusion: Traditional arguments for the low adoption of POU products focus on affordability, consumers' lack of information about germs and the dangers of unsafe water, and specific products not meshing with a household's preferences. In this study we provided free trials, repeated informational messages explaining the dangers of untreated water, and a variety of product designs. The low usage of all products despite such efforts makes clear that important barriers exist beyond cost, information, and variation among these four product designs. Without a better understanding of the choices and aspirations of the target end-users, household-based water treatment is unlikely to reduce morbidity and mortality substantially in urban Bangladesh and similar populations.

Household point-of-use (POU) water treatment technologies targeted at vulnerable populations are microbiologically effective and, in small trials, improve health. We do not understand the factors that influence preference for and adoption of these technologies by target end-users. We cycled 400 rural subsistence farm households in western Kenya through three randomly ordered two-month trials of three POU products: dilute hypochlorite solution, porous ceramic filtration, and a combined flocculant-disinfectant powdered mixture to compare relative end-user preferences and usage. Households reported higher usage of both dilute hypochlorite and filters than the flocculant-disinfectant. Averaged among all participating households, Escherichia coli reductions in treated water were generally higher among those that received dilute hypochlorite solution than among those receiving either of the other two products. Among those households that self-reported product usage, the E. coli reductions achieved by dilute hypochlorite and the flocculant-disinfectant are statistically equivalent to one another and higher than the reductions achieved by filters. At the same time, households ranked filters most frequently as their most preferred product.

Background: Combined oral contraceptives (COC) and depot-medroxyprogesterone acetate (DMPA) are among the most widely used family planning methods; their effect on HIV acquisition is not known., Objective: To evaluate the effect of COC and DMPA on HIV acquisition and any modifying effects of other sexually transmitted infections., Methods: This multicenter prospective cohort study enroled 6109 HIV-uninfected women, aged 18-35 years, from family planning clinics in Uganda, Zimbabwe and Thailand. Participants received HIV testing quarterly for 15-24 months. The risk of HIV acquisition with different contraceptive methods was assessed (excluding Thailand, where there were few HIV cases)., Results: HIV infection occurred in 213 African participants (2.8/100 woman-years). Use of neither COC [hazard ratio (HR), 0.99; 95% confidence interval (CI), 0.69-1.42] nor DMPA (HR, 1.25; 95% CI, 0.89-1.78) was associated with risk of HIV acquisition overall, including among participants with cervical or vaginal infections. While absolute risk of HIV acquisition was higher among participants who were seropositive for herpes simplex virus 2 (HSV-2) than in those seronegative at enrolment, among the HSV-2-seronegative participants, both COC (HR, 2.85; 95% CI, 1.39-5.82) and DMPA (HR, 3.97; 95% CI, 1.98-8.00) users had an increased risk of HIV acquisition compared with the non-hormonal group., Conclusions: No association was found between hormonal contraceptive use and HIV acquisition overall. This is reassuring for women needing effective contraception in settings of high HIV prevalence. However, hormonal contraceptive users who were HSV-2 seronegative had an increased risk of HIV acquisition. Additional research is needed to confirm and explain this finding.

Objective: To examine the acceptability of five nonoxynol-9 (N-9) spermicides., Methods: We analyzed data from a randomized trial of five products, including three gels containing different amounts of N-9 per dose, a film and a suppository. In the trial, 1536 participants were asked to use the assigned spermicide for 7 months and to complete questionnaires 4 weeks after admission and at discontinuation., Results: Overall, 43% of participants liked their spermicide "very much." This proportion was higher in the three gel groups than in the suppository and film groups. Difficulty with insertion, messiness and discontent with timing of insertion were common complaints in all groups. After adjustment for selected baseline factors, acceptability on the first questionnaire was not related to duration or consistency of subsequent spermicide use or to subsequent time to pregnancy., Conclusions: In this study, all five spermicides were considered acceptable by most users. Acceptability did not appear to influence spermicide use or pregnancy risk.

Smoking has been identified as one of the health priority areas to be addressed by the Public Health Service's Objectives for the Nation initiative. Several gains in moving toward the 1990 goals for smoking and health have been recorded. Only 32.6 percent of the U.S. population over 16 years old were smokers in 1980, compared with 41.7 percent in 1965. The proportion of high school seniors who were daily smokers fell from nearly 30 percent in 1977 to 20 percent in 1981. Changes in smoking prevalence were related to critical events, such as the Surgeon General's reports on smoking. A variety of information and education programs aimed at specific groups are being carried out by Federal, State, and local governmental agencies and voluntary health organizations.

Cancer is the second most frequent cause of death in this country. Unlike deaths from other major diseases, cancer deaths have continued to increase in the last several decades, because of the rise in cancer deaths attributable to cigarette smoking, and in particular, to the risk in deaths from lung cancer. The total number of cancer deaths attributable to smoking is shown in table 4. Off 401,000 such deaths observed in 1978, a total of 122,000 or 30 percent may be attributed to smoking. These included some 80,000 deaths from lung cancer and 13,000 deaths from cancer of the mouth, pharynx, larynx, or esophagus. In all, 43 percent of cancer deaths among males and 15 percent among females were attributed to cigarette smoking. Applying this 30 percent figure to the estimated number of cancer deaths in 1982 results in an estimated 129,000 cigarette-related cancer deaths.

1. Propranolol, as the racemate and the (+)- and (-)-isomers (400 mug/l.) and practolol (50 mg/l.) were tested for their effects on atrial and ventricular rates and on the duration of overdrive suppression (ODI) in isolated perfused cat hearts with surgically-induced heart block.2. Racemic propranolol and the (+)- and (-)-isomers prolonged ODI and slowed the rate of the ventricular pacemaker; the (+)- and (-)-isomers also reduced the rate of the atrial pacemaker. Practolol shortened ODI and increased the rate of the atrial and ventricular pacemakers.3. The (+)- and (-)-isomers were more potent than the racemate; the (-)-isomer was more potent than the (+)-isomer. The results suggest there is a stereospecific mechanism involved in the biological distribution of propranolol.4. Twenty-four hours after reserpine treatment (5 mg/kg, i.p.) practolol continued to increase the rate of the atrial and ventricular pacemakers but did not shorten ODI.5. The mechanism by which these agents affect myocardial excitability and automaticity is discussed.