Global burden and trends of rotavirus infection-associated deaths from 1990 to 2019: an observational trend study

Background

Rotavirus is the leading global pathogen of diarrhea-associated mortality and poses a great threat to public health in all age groups. This study aimed to explore the global burden and 30-year change patterns of rotavirus infection-associated deaths.

Methods

Based on the Global Burden of Disease 2019 Study (GBD 2019), we analyzed the age-standardized death rate (ASDR) of rotavirus infection by sex, geographical region, and sociodemographic index (SDI) from 1990 to 2019. A Joinpoint regression model was used to analyze the global trends in rotavirus infection over the 30 years, SaTScan software was used to detect the spatial and temporal aggregations, and a generalized linear model to explore the relationship between sociodemographic factors and death rates of rotavirus infection.

Results

Globally, rotavirus infection was the leading cause of diarrheal deaths, accounting for 19.11% of deaths from diarrhea in 2019. Rotavirus caused a higher death burden in African, Oceanian, and South Asian countries in the past three decades. The ASDR of rotavirus declined from 11.39 (95% uncertainty interval [95% UI] 5.46–19.48) per 100,000 people in 1990 to 3.41 (95% UI 1.60–6.01) per 100,000 people in 2019, with an average annual percentage change (AAPC) (− 4.07%, P < 0.05). However, a significant uptrend was found in high-income North America (AAPC = 1.79%, P < 0.05). The death rate was the highest among children under 5 years worldwide. However, the death rates of elderly individuals over 70 years were higher than those of children under 5 years in 2019 among high, high-middle, middle, and low-middle SDI regions. Current health expenditure, gross domestic product per capita, and the number of physicians per 1000 people were significantly negatively correlated with death rates of rotavirus.

Conclusions

Although the global trends in the rotavirus burden have decreased substantially over the past three decades, the burden of rotavirus remained high in Africa, Oceania, and South Asia. Children under 5 years and elderly individuals over 70 years were the populations most at risk for rotavirus infection-associated deaths, especially elderly individuals over 70 years in relatively high SDI regions. More attention should be paid to these areas and populations, and effective public health policies should be implemented in the future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12985-022-01898-9.

Global Burden and Trends of Norovirus-Associated Diseases From 1990 to 2019: An Observational Trend Study

Introduction

As an important pathogen causing diarrheal diseases, the burden and change in the death rate of norovirus-associated diseases (NADs) globally are still unknown.

Methods

Based on global disease burden data from 1990 to 2019, we analyzed the age-standardized death rate (ASDR) of NADs by age, region, country, and Socio-Demographic Index (SDI) level. The discrete Poisson model was applied in the analysis of NADs' spatiotemporal aggregation, the Joinpoint regression model to analyze the trend of death burden of NADs over 30 years, and a generalized linear model to identify the risk factors for the death rate from NADs.

Results

The ASDR of NADs significantly decreased by a factor of approximately 2.7 times, from 5.02 (95% CI: 1.1, 11.34) in 1990 to 1.86 (95% CI: 0.36, 4.16) in 2019 [average annual percent change (AAPC) = −3.43, 95% CI: −3.56, −3.29]. The death burden of NADs in 2019 was still highest in African regions despite a great decline in recent decades. However, the ASDR in high SDI countries presented an uptrend [0.12 (95% CI: 0.03, 0.26) in 1990 and 0.24 (95% CI: 0.03, 0.53) in 2019, AAPC = 2.52, 95% CI: 2.02–3.03], mainly observed in the elderly over 70 years old. Compared to children under 5 years old, the 2019 death rate of elderly individuals over 80 years old was much higher in high SDI countries. The generalized linear model showed that factors of the number of physicians (RR = 0.67), the proportions of children under 14 years old (RR = 1.21), elderly individuals over 65 years old (RR = 1.13), educational level (RR = 1.03) and urbanization proportion (RR = 1.01) influenced the ASDR of NADs.

Conclusions

The death burden of NADs has remained high in developing regions over the last three decades and has increased among the elderly in countries with high SDI levels, even though the global trend in NAD-associated deaths has decreased significantly in the past three decades. More effective public health policies against NADs need to be implemented in high SDI regions and for the elderly.

Approach to user group-specific assessment of urban green spaces for a more equitable supply exemplified by the elderly population

The use of urban green spaces (UGS) depends on its quality, which is perceived very differently by diverse socio-demographic groups. In particular, elderly people have special demands on the UGS quality. It is essential to know these demands to create an equitable UGS supply. We present an approach to determining some qualitative aspects and the supply of cultural ecosystem services of diverse forms of UGS. This is realised by combining user demands with actual UGS features. In a concrete example, we assessed the UGS quality and supply for both the general population and the subset of elderly people. For the latter group, the activities of relaxing and observing nature, as well as the UGS feature of benches, were found to be significantly more important than for the general population. Nevertheless, this had only a minor impact on the assessed aspects of UGS quality and supply, with little differences detected between the two groups. In Dresden (Germany), we determined that almost half of the elderly population are not provided with high-quality UGS. In these areas, urban planning must increase the UGS quality while taking user demands into account to ensure just access to the positive benefits of UGS for the elderly.

Utilization patterns, outcomes and costs of a simplified acute malnutrition treatment programme in Burkina Faso

Access to treatment for acute malnutrition remains a challenge, in part due to the fragmentation of treatment programmes based on case severity. This paper evaluates utilization patterns, outcomes and associated costs for treating acute malnutrition cases among a cohort of children in Burkina Faso. This study is a secondary analysis of a proof‐of‐concept trial, called Optimizing treatment for acute Malnutrition (OptiMA), conducted in Burkina Faso in 2016. A total of 4958 eligible children whose mid‐upper arm circumference (MUAC) was less than 125 mm or with oedema were followed weekly and given ready‐to‐use therapeutic foods (RUTF). We evaluated the service utilization and outcomes among patients and estimated resource use and variable cost per patient, and examined factors driving variation in resource use. Children with lower initial MUAC level grew faster but required more time to recover than those with higher initial MUAC level. They also had higher rates of death, default and nonresponse. The simplified OptiMA approach for treating acute malnutrition achieved high rates of recovery overall (84%), especially among less severe cases, with modest quantities of RUTF. The average overall variable cost per child admitted was US$38.0 (SD: 20.5) half of which was accounted for by the cost of RUTF. Cost per recovered case was correlated with case severity, ranging from US$35.1 to US$132.8. If simplified integrated programmes using severity‐based RUTF dosing can increase access to treatment at earlier, less severe stages of acute malnutrition, they can help avoid more serious and costlier cases.

This paper evaluates utilization patterns, outcomes, and associated costs for treating acute malnutrition cases among a cohort of children in Burkina Faso.

Children with lower initial mid upper arm circumference (MUAC) level grew faster but required more time to recover than those with higher initial MUAC level.

The average cost per child admitted was US$38.0 half of which was accounted for by the cost of ready to use therapeutic foods (RUTF).

If simplified programs can increase access to treatment at earlier, less severe stages of acute malnutrition, they can help avoid more serious and costlier cases.

Costs of Implementing an Integrated Package of Maternal and Pediatric Interventions Including SQ-LNS in Rural Niger

BACKGROUND

In January 2015, the Alliance for International Medical Action and Bien Être de la Femme et de l'Enfant au Niger launched the 1000 Days Program in Mirriah District, Niger, to provide an integrated package of maternal and pediatric preventive and curative interventions. A new component of the package was the provision of small-quantity lipid-based nutritional supplements (SQ-LNS) for children 6 to 23 months.

OBJECTIVE

The objective of this study was to estimate the costs associated with providing the 1000 days package.

METHODS

Activity-based costing was used to estimate the total costs of the 10 activities included in the 1000 days package and also the incremental costs of new interventions, those beyond the standard of care.

RESULTS

The total cost of the 1000 Days Program was US$2.31 million for 9000 mother-child pairs. The average cost per pair was US$257 or US$103 per year. Incremental costs for new interventions accounted for 56% of program costs. Small-quantity lipid-based nutritional supplement represented 30% of incremental costs. A combination of efficiency measures could lower program costs by 15%.

CONCLUSIONS

This study is the first to estimate the costs of an integrated, preventative-curative package of maternal-child health interventions with SQ-LNS. Implementing the 1000 days package across Niger will be challenging with only the country's domestic health resources. Efficiency measures and creative financing arrangements, including support from external partners, should be explored. The approach and results described can inform future resource mobilization, financing, and budgeting efforts to scale the 1000 days or similar programs.

AB0255 BASELINE CHARACTERISTICS OF PATIENTS WITH RHEUMATOID ARTHRITIS TREATED WITH UPADACITINIB IN GERMAN REAL-WORLD PRACTICE: RESULTS FROM THE POST-MARKETING OBSERVATIONAL UPwArds STUDY

Background:

The efficacy and safety of upadacitinib (UPA), a selective Janus kinase inhibitor, has been evaluated in the SELECT rheumatoid arthritis (RA) clinical program,1–6 but its real-world effectiveness remains to be investigated. The UPwArds study will assess the association of C-reactive protein (CRP) level with remission and other efficacy outcomes in patients with RA treated with UPA in German real-world practice.

Objectives:

To describe the baseline characteristics of patients enrolled in the UPwArds study.

Methods:

The prospective, open-label, multicenter, non-interventional, post-marketing UPwArds study included adult patients with moderate-to-severe RA (swollen joint count [SJC28] ≥3 and inadequate response or intolerance to ≥1 disease-modifying antirheumatic drug [DMARD]). Patients were treated with UPA 15 mg once daily, as monotherapy or in combination with methotrexate (MTX; 50:50 mono:combo enrollment planned), according to the German label. Variables assessed included medical history (disease duration, previous RA therapy, and vaccination status), CRP level, and disease activity (disease activity score [DAS28(CRP)], tender joint count [TJC28], and SJC28). There was no recruitment restriction regarding CRP level. This descriptive interim analysis reports patient baseline characteristics after enrollment was complete. All data were analyzed as observed, with no imputation of missing data.

Results:

533 patients (UPA monotherapy: 257 [48%]; UPA plus MTX: 276 [52%]) were included. Mean patient age was 58 years; mean disease duration was 9 years (Table 1). Despite having active RA, almost half the population (44%; n=237) did not have elevated CRP at the start of UPA treatment. Mean DAS28(CRP) was 4.6; mean TJC28 and SJC28 were 7.7 and 5.6, respectively. Overall, 39% of patients had not been treated with any biologic (b) DMARD or targeted synthetic (ts) DMARD before enrollment; 25% and 36% had previously been treated with 1 or ≥2 bDMARDs or tsDMARDs, respectively (Figure 1). 8.7% of patients had previously received a herpes zoster vaccination (8.1% Shingrix; 0.6% Zostavax).

Conclusion:

In German clinical practice, the population of patients with RA in the UPwArds study was predominantly treatment-refractory. Half of these patients had no elevated CRP despite active disease; future analyses will assess the impact of CRP on efficacy outcomes.

References:

[1]Smolen JS, et al. Lancet 2019;393:2303–11;

[2]Burmester GR, et al. Lancet 2018;391:2503–12;

[3]Genovese MC, et al. Lancet 2018;391:2513–24;

[4]van Vollenhoven R, et al. Arthritis Rheumatol 2020;72:1607–20;

[5]Fleischmann R, et al. Arthritis Rheumatol 2019;71:1788–800;

[6]Rubbert-Roth A, et al. N Engl J Med 2020;383:1511–21.

Table 1.

Baseline characteristics

Age, yearsUPAUPA + MTXTotal57.7 (13.2)n=25758.1 (11.4)n=27657.9 (12.3)n=533Disease duration, years9.4 (8.3)8.5 (7.7)9.0 (8.0)n=253n=272n=525CRP, mg/dL1.3 (1.9)1.1 (1.7)1.2 (1.8)n=257n=276n=533CRP >ULN, n (%)137 (53.3)159 (57.6)296 (55.5)n=257n=276n=533TJC287.4 (6.0)7.9 (6.4)7.7 (6.2)n=257n=276n=533SJC285.5 (3.7)5.6 (4.1)5.6 (3.9)n=257n=276n=533Patient’s Global Assessment6.2 (1.9)6.3 (1.8)6.3 (1.8)n=257n=276n=533Physician’s Global Assessment5.8 (1.5)5.9 (1.6)5.9 (1.6)n=257n=276n=533DAS28(CRP)4.6 (1.0)4.6 (1.0)4.6 (1.0)n=257n=276n=533DAS28(ESR)4.8 (1.1)4.9 (1.2)4.9 (1.1)n=224n=239n=463CDAI24.9 (10.2)25.7 (10.8)25.4 (10.5)n=257n=276n=533SDAI26.2 (10.5)26.9 (11.3)26.6 (10.9)n=257n=276n=533RAID5.7 (2.0)5.7 (2.0)5.7 (2.0)n=255n=275n=530Pain (RAID-1)6.2 (2.2)6.1 (2.3)6.2 (2.2)n=255n=275n=530SF-12 Physical Component Summary32.6 (8.5)33.9 (8.6)33.3 (8.6)n=245n=262n=507SF-12 Mental Component Summary42.4 (11.6)42.6 (11.3)42.5 (11.5)n=245n=262n=507HAQ-DI1.3 (0.7)1.3 (0.6)1.3 (0.6)n=250n=270n=520PHQ-98.9 (5.3)8.6 (5.3)8.7 (5.3)n=252n=272n=524Erosions, n (%)87 (33.9)95 (34.4)182 (34.1)n=257n=276n=533

Data are mean (SD), n unless otherwise stated

Acknowledgements:

AbbVie funded this study; contributed to its design; participated in data collection, analysis, and interpretation of the data; and in the writing, review, and approval of the abstract. AbbVie and the authors thank all study investigators for their contributions and the patients who participated in this study. No honoraria or payments were made for authorship. Medical writing support was provided by Grant Thomas Kirkpatrick, MSc, of 2 the Nth (Cheshire, UK), and was funded by AbbVie.

Disclosure of Interests:

Torsten Witte Grant/research support from: AbbVie, Amgen, Bristol-Myers Squibb, Celgene, Chugai, Gilead, Janssen, Lilly, MSD, Mylan, Novartis, Pfizer, Roche, and UCB., Uta Kiltz Consultant of: AbbVie, Biocad, Eli Lilly and Company, Grünenthal, Hexal, Janssen, MSD, Novartis, Pfizer, Roche, and UCB, Grant/research support from: AbbVie, Amgen, Biogen, Fresenius, GSK, Hexal, Novartis, and Pfizer, Florian Haas Consultant of: AbbVie, Celgene, Novartis, and Pfizer, Grant/research support from: AbbVie, BMS, Celgene, Chugai, MSD, Novartis, Pfizer, Roche, and Sanofi Genzyme, Elke Riechers Consultant of: AbbVie, Chugai, Novartis, and UCB, Grant/research support from: AbbVie, Chugai, Lilly, Janssen, Novartis, Pfizer, Roche, and UCB, Ulrich Prothmann Grant/research support from: AbbVie, Amgen, Bristol-Myers Squibb, Chugai, Glaxo Smith Kline, Novartis, Pfizer, Roche, Sanofi, SOBI, and UCB, Daniela Adolf Employee of: Employee of StatConsult and may own stock or options, Carsten Holland Employee of: Employee of AbbVie and may own stock or options, Rouven Hecht Employee of: Employee of AbbVie and may own stock or options, Alexander Roessler Employee of: Employee of AbbVie and may own stock or options, Kirsten Famulla Employee of: Employee of AbbVie and may own stock or options, Klaus Krueger Grant/research support from: AbbVie, Biogen, BMS, Celltrion, Gilead, Hexal, Janssen, Lilly, Medac, MSD, Novartis, Pfizer, Roche, and UCB.

Modeling Combination Hepatitis C Virus Treatment and Prevention Strategies in a Network of People Who Inject Drugs in the United States

BACKGROUND

Hepatitis C virus (HCV) treatment as prevention (TasP) strategies can contribute to HCV microelimination, yet complimentary interventions such as opioid agonist therapies (OAT) with methadone or buprenorphine and syringe services programs (SSPs) may improve the prevention impact. This modeling study estimates the impact of scaling up the combination of OAT and SSPs with HCV TasP in a network of people who inject drugs (PWID) in the United States.

METHODS

Using empirical data from Hartford, Connecticut, we deployed a stochastic block model to simulate an injection network of 1574 PWID. We used a susceptible-infected model for HCV and human immunodeficiency virus to evaluate the effectiveness of several HCV TasP strategies, including in combination with OAT and SSP scale-up, over 20 years.

RESULTS

At the highest HCV prevalence (75%), when OAT coverage is increased from 10% to 40%, combined with HCV treatment of 10% per year and SSP scale up to 40%, the time to achieve microelimination is reduced from 18.4 to 11.6 years. At the current HCV prevalence (60%), HCV TasP strategies as low as 10% coverage per year may achieve HCV microelimination within 10 years, with minimal impact from additional OAT scale-up. Strategies based on mass initial HCV treatment (50 per 100 PWID the first year followed by 5 per 100 PWID thereafter) were most effective in settings with HCV prevalence of 60% or lower.

CONCLUSIONS

Scale-up of HCV TasP is the most effective strategy for microelimination of HCV. OAT scale-up, however, scale-up may be synergistic toward achieving microelimination goals when HCV prevalence exceeds 60% and when HCV treatment coverage is 10 per 100 PWID per year or lower.

The epidemiological and radiographical characteristics of asymptomatic infections with the novel coronavirus (COVID-19): A systematic review and meta-analysis

Objectives

The role of asymptomatic infections in the transmission of COVID-19 have drawn considerable attention. Here, we performed a meta-analysis to summarize the epidemiological and radiographical characteristics of asymptomatic infections associated with COVID-19.

Methods

Data on the epidemiological and radiographical characteristics of asymptomatic infections were extracted from the existing literature. Pooled proportions with 95% confidence intervals were then calculated using a random effects model.

Results

A total of 104 studies involving 20,152 cases were included. The proportion of asymptomatic individuals among those with COVID-19 was 13.34% (10.86%–16.29%), among which presymptomatic and covert infections accounted for 7.64% (4.02%–14.04%) and 8.44% (5.12%–13.62%), respectively. The proportions of asymptomatic infections among infected children and healthcare workers were 32.24% (23.08%–42.13%) and 36.96% (18.51%–60.21%), respectively. The proportion of asymptomatic infections was significantly higher after 2020/02/29 than before (33.53% vs 10.19%) and in non-Asian regions than in Asia (28.76% vs 11.54%). The median viral shedding duration of asymptomatic infections was 14.14 days (11.25–17.04). A total of 47.62% (31.13%–72.87%) of asymptomatic infections showed lung abnormalities, especially ground-glass opacity (41.11% 19.7%–85.79%).

Conclusions

Asymptomatic infections were more commonly found in infected children and healthcare workers and increased after 2020/02/29 and in non-Asian regions. Chest radiographical imaging could be conducive to the early identification of asymptomatic infections.

Twenty Years Of Antiretroviral Therapy For People Living With HIV: Global Costs, Health Achievements, Economic Benefits

Since the introduction of azidothymidine in 1987, significant improvements in treatment for people living with HIV have yielded substantial improvements in global health as a result of the unique benefits of antiretroviral therapy (ART). ART averted 9.5 million deaths worldwide in 1995-2015, with global economic benefits of $1.05 trillion. For every $1 spent on ART, $3.50 in benefits accrued globally. If treatment scale-up achieves the global 90-90-90 targets of the Joint United Nations Programme on HIV/AIDS, a total of 34.9 million deaths are projected to be averted between 1995 and 2030. Approximately 40.2 million new HIV infections could also be averted by ART, and economic gains could reach $4.02 trillion in 2030. Having provided ART to 19.5 million people represents a major human achievement. However, 15.2 million infected people are currently not receiving treatment, which represents a significant lost opportunity. Further treatment scale-up could yield even greater health and economic benefits.

Hepatitis C virus elimination in Indonesia: Epidemiological, cost and cost-effectiveness modelling to advance advocacy and strategic planning

BACKGROUNDS & AIMS

In Indonesia 1.9 million people are chronically infected with hepatitis C virus (HCV), but a national strategic plan for elimination has not yet been developed, despite the availability of low-cost treatments which could save many lives. We used epidemiological and cost modelling to estimate targets and resource requirements of a national elimination program and explore the potential impact and cost-effectiveness.

METHODS

To model the HCV epidemic, we used a dynamic model, parameterised with Indonesia-specific data, accounting for disease progression, injecting drug use and demographics. Future scale-up scenarios were designed for 2018-2050 to capture possible policy choices. Costs of an initial 5-year national strategy and of long-term elimination were estimated for the most feasible scenario, as agreed with government and local partners. Cost savings from reduced drug and diagnostics prices were also estimated. The cost-effectiveness of baseline predictions and those with drug price reductions were compared to the no treatment scenario.

RESULTS

Elimination by 2045, considered the most feasible path to scale-up, would prevent 739 000 new infections and avert 158 000 HCV-related deaths. The costs would be $5.6 billion (USD) using baseline prices but could fall to $2.7 billion if price reductions for HCV drugs and diagnostics are secured. With these price reductions, the incremental cost-effectiveness ratio for a 2045 elimination program would be cost-effective at $300 (USD) per year of life saved vs the no treatment scenario.

CONCLUSIONS

This study has underpinned advocacy efforts to secure Indonesian government commitment to HCV elimination, and provides further inputs for HCV strategic planning efforts.

Estimating the Population Size of People Who Inject Drugs in Malaysia for 2014 and 2017 Using the Benchmark-Multiplier Method

Background: As hepatitis C elimination efforts are launched, national strategies for screening and treatment scale-up in countries, such as Malaysia, must be designed and implemented. Strategic information, including estimates of the total number of patients chronically-infected with hepatitis C virus (HCV) and the size of key populations, such as people who inject drugs (PWID), is critical to informing these efforts. For Malaysia, the estimate of the PWID population size most frequently reported in global systematic reviews is for the year 2009. Objectives: To support ongoing national HCV planning efforts, we aimed to estimate the national population size of active PWID in Malaysia, for the years 2014 and 2017. Methods: To estimate the PWID population size, we applied standard benchmark-multiplier methodology, frequently used for PWID population size estimation, and extended it by adjusting for cessation of injecting drug use within the benchmark and calculating statistical uncertainty intervals. Results: The estimated active PWID population size was 153,000 (95% uncertainty interval (UI): 136,000-172,000) for 2014 and 156,000 (95% UI: 137,000-188,000) for 2017. Conclusions/importance: This updated estimate of the active PWID population size in Malaysia will help inform effective planning for the scale-up of HCV screening and treatment services. The proposed methodology is applicable to other countries that maintain national HIV registries and have conducted Integrated Biological and Behavioral Surveys among active PWID.

A Stepwise Approach to a National Hepatitis C Screening Strategy in Malaysia to Meet the WHO 2030 Targets: Proposed Strategy, Coverage, and Costs

BACKGROUND

In Malaysia, more than 330 000 individuals are estimated to be chronically infected with hepatitis C virus (HCV), but less than 2% have been treated to date.

OBJECTIVES

To estimate the required coverage and costs of a national screening strategy to inform the launch of an HCV elimination program.

METHODS

We designed an HCV screening strategy based on a "stepwise" approach. This approach relied on targeting of people who inject drugs in the early years, with delayed onset of widespread general population screening. Annual coverage requirements and associated costs were estimated to ensure that the World Health Organization elimination treatment targets were met.

RESULTS

In total, 6 million individuals would have to be screened between 2018 and 2030. Targeting of people who inject drugs in the early years would limit annual screening coverage to less than 1 million individuals from 2018 to 2026. General population screening would have to be launched by 2026. Total costs were estimated at MYR 222 million ($58 million). Proportional to coverage targets, 60% of program costs would fall from 2026 to 2030.

CONCLUSIONS

This exercise was one of the first attempts to conduct a detailed analysis of the required screening coverage and costs of a national HCV elimination strategy. These findings suggest that the stepwise approach could delay the onset of general population screening by more than 5 years after the program's launch. This delay would allow additional time to mobilize investments required for a successful general population screening program and also minimize program costs. This strategy prototype could inform the design of effective screening strategies in other countries.

The investment case for hepatitis B and C in South Africa: adaptation and innovation in policy analysis for disease program scale-up

Even though WHO has approved global goals for hepatitis elimination, most countries have yet to establish programs for hepatitis B and C, which account for 320 million infections and over a million deaths annually. One reason for this slow response is the paucity of robust, compelling analyses showing that national HBV/HCV programs could have a significant impact on these epidemics and save lives in a cost-effective, affordable manner. In this context, our team used an investment case approach to develop a national hepatitis action plan for South Africa, grounded in a process of intensive engagement of local stakeholders. Costs were estimated for each activity using an ingredients-based, bottom-up costing tool designed by the authors. The health impact and cost-effectiveness of the Action Plan were assessed by simulating its four priority interventions (HBV birth dose vaccination, PMTCT, HBV treatment and HCV treatment) using previously developed models calibrated to South Africa's demographic and epidemic profile. The Action Plan is estimated to require ZAR3.8 billion (US$294 million) over 2017-2021, about 0.5% of projected government health spending. Treatment scale-up over the initial 5-year period would avert 13 000 HBV-related and 7000 HCV-related deaths. If scale up continues beyond 2021 in line with WHO goals, more than 670 000 new infections, 200 000 HBV-related deaths, and 30 000 HCV-related deaths could be averted. The incremental cost-effectiveness of the Action Plan is estimated at $3310 per DALY averted, less than the benchmark of half of per capita GDP. Our analysis suggests that the proposed scale-up can be accommodated within South Africa's fiscal space and represents good use of scarce resources. Discussions are ongoing in South Africa on the allocation of budget to hepatitis. Our work illustrates the value and feasibility of using an investment case approach to assess the costs and relative priority of scaling up HBV/HCV services.

Reaching the global target to reduce stunting: an investment framework

Childhood stunting, being short for one's age, has life-long consequences for health, human capital and economic growth. Being stunted in early childhood is associated with slower cognitive development, reduced schooling attainment and adult incomes decreased by 5-53%. The World Health Assembly has endorsed global nutrition targets including one to reduce the number of stunted children under five by 40% by 2025. The target has been included in the Sustainable Development Goals (SDG target 2.2). This paper estimates the cost of achieving this target and develops scenarios for generating the necessary financing. We focus on a key intervention package for stunting (KIPS) with strong evidence of effectiveness. Annual scale-up costs for the period of 2016-25 were estimated for a sample of 37 high burden countries and extrapolated to all low and middle income countries. The Lives Saved Tool was used to model the impact of the scale-up on stunting prevalence. We analysed data on KIPS budget allocations and expenditure by governments, donors and households to derive a global baseline financing estimate. We modelled two financing scenarios, a 'business as usual', which extends the current trends in domestic and international financing for nutrition through 2025, and another that proposes increases in financing from all sources under a set of burden-sharing rules. The 10-year financial need to scale up KIPS is US$49.5 billion. Under 'business as usual', this financial need is not met and the global stunting target is not reached. To reach the target, current financing will have to increase from US$2.6 billion to US$7.4 billion a year on average. Reaching the stunting target is feasible but will require large coordinated investments in KIPS and a supportive enabling environment. The example of HIV scale-up over 2001-11 is instructive in identifying the factors that could drive such a global response to childhood stunting.

PrEP for key populations in combination HIV prevention in Nairobi: a mathematical modelling study

BACKGROUND

The HIV epidemic in the population of Nairobi as a whole is in decline, but a concentrated sub-epidemic persists in key populations. We aimed to identify an optimal portfolio of interventions to reduce HIV incidence for a given budget and to identify the circumstances in which pre-exposure prophylaxis (PrEP) could be used in Nairobi, Kenya.

METHODS

A mathematical model was developed to represent HIV transmission in specific key populations (female sex workers, male sex workers, and men who have sex with men [MSM]) and among the wider population of Nairobi. The scale-up of existing interventions (condom promotion, antiretroviral therapy, and male circumcision) for key populations and the wider population as have occurred in Nairobi is represented. The model includes a detailed representation of a PrEP intervention and is calibrated to prevalence and incidence estimates specific to key populations and the wider population.

FINDINGS

In the context of a declining epidemic overall but with a large sub-epidemic in MSM and male sex workers, an optimal prevention portfolio for Nairobi should focus on condom promotion for male sex workers and MSM in particular, followed by improved antiretroviral therapy retention, earlier antiretroviral therapy, and male circumcision as the budget allows. PrEP for male sex workers could enter an optimal portfolio at similar levels of spending to when earlier antiretroviral therapy is included; however, PrEP for MSM and female sex workers would be included only at much higher budgets. If PrEP for male sex workers cost as much as US$500, average annual spending on the interventions modelled would need to be less than $3·27 million for PrEP for male sex workers to be excluded from an optimal portfolio. Estimated costs per infection averted when providing PrEP to all female sex workers regardless of their risk of infection, and to high-risk female sex workers only, are $65 160 (95% credible interval [CrI] $43 520-$90 250) and $10 920 (95% CrI $4700-$51 560), respectively.

INTERPRETATION

PrEP could be a useful contribution to combination prevention, especially for under-served key populations in Nairobi. An ongoing demonstration project will provide important information regarding practical aspects of implementing PrEP for key populations in this setting.

FUNDING

The Bill & Melinda Gates Foundation.

Funding AIDS programmes in the era of shared responsibility: an analysis of domestic spending in 12 low-income and middle-income countries

BACKGROUND

As the incomes of many AIDS-burdened countries grow and donors' budgets for helping to fight the disease tighten, national governments and external funding partners increasingly face the following question: what is the capacity of countries that are highly affected by AIDS to finance their responses from domestic sources, and how might this affect the level of donor support? In this study, we attempt to answer this question.

METHODS

We propose metrics to estimate domestic AIDS financing, using methods related to national prioritisation of health spending, disease burden, and economic growth. We apply these metrics to 12 countries in sub-Saharan Africa with a high prevalence of HIV/AIDS, generating scenarios of possible future domestic expenditure. We compare the results with total AIDS financing requirements to calculate the size of the resulting funding gaps and implications for donors.

FINDINGS

Nearly all 12 countries studied fall short of the proposed expenditure benchmarks. If they met these benchmarks fully, domestic spending on AIDS would increase by 2·5 times, from US$2·1 billion to $5·1 billion annually, covering 64% of estimated future funding requirements and leaving a gap of around a third of the total $7·9 billion needed. Although upper-middle-income countries, such as Botswana, Namibia, and South Africa, would become financially self-reliant, lower-income countries, such as Mozambique and Ethiopia, would remain heavily dependent on donor funds.

INTERPRETATION

The proposed metrics could be useful to stimulate further analysis and discussion around domestic spending on AIDS and corresponding donor contributions, and to structure financial agreements between recipient country governments and donors. Coupled with improved resource tracking, such metrics could enhance transparency and accountability for efficient use of money and maximise the effect of available funding to prevent HIV infections and save lives.

FUNDING

US Centers for Disease Control and Prevention.

Overcoming challenges to sustainable immunization financing: early experiences from GAVI graduating countries

Over the 5-year period ending in 2018, 16 countries with a combined birth cohort of over 6 million infants requiring life-saving immunizations are scheduled to transition (graduate) from outside financial and technical support for a number of their essential vaccines. This support has been provided over the past decade by the GAVI Alliance. Will these 16 countries be able to continue to sustain these vaccination efforts? To address this issue, GAVI and its partners are supporting transition planning, entailing country assessments of readiness to graduate and intensive dialogue with national officials to ensure a smooth transition process. This approach was piloted in Bhutan, Republic of Congo, Georgia, Moldova and Mongolia in 2012. The pilot showed that graduating countries are highly heterogeneous in their capacity to assume responsibility for their immunization programmes. Although all possess certain strengths, each country displayed weaknesses in some of the following areas: budgeting for vaccine purchase, national procurement practices, performance of national regulatory agencies, and technical capacity for vaccine planning and advocacy. The 2012 pilot experience further demonstrated the value of transition planning processes and tools. As a result, GAVI has decided to continue with transition planning in 2013 and beyond. As the graduation process advances, GAVI and graduating countries should continue to contribute to global collective thinking about how developing countries can successfully end their dependence on donor aid and achieve self-sufficiency.

Financing vaccinations - the South African experience

South Africa provides a useful country case study for financing vaccinations. It has been an early adopter of new vaccinations and has financed these almost exclusively from domestic resources, largely through general taxation. National vaccination policy is determined by the Department of Health, based on advice from a national advisory group on immunisation. Standard health economic criteria of effectiveness, cost-effectiveness, affordability and burden of disease are used to assess whether new vaccinations should be introduced. Global guidelines and the advice of local and international experts are also helpful in making the determination to introduce new vaccines. In terms of recent decisions to introduce new vaccines against pneumococcal disease and rotavirus diarrhoea in children, the evidence has proved unequivocal. Universal rollout has been implemented even though this has led to a fivefold increase in national spending on vaccines. The total cost to government remains below 1-1.5% of public expenditures for health, which is viewed by the South African authorities as affordable and necessary given the number of lives saved and morbidity averted. To manage the rapid increase in domestic spending, efforts have been made to scale up coverage over several years, give greater attention to negotiating price reductions and, in some cases, obtain initial donations or frontloaded deliveries to facilitate earlier universal rollout. There has been strong support from a wide range of stakeholders for the early introduction of new generation vaccines.

Economic returns to investment in AIDS treatment in low and middle income countries

Since the early 2000s, aid organizations and developing country governments have invested heavily in AIDS treatment. By 2010, more than five million people began receiving antiretroviral therapy (ART)--yet each year, 2.7 million people are becoming newly infected and another two million are dying without ever having received treatment. As the need for treatment grows without commensurate increase in the amount of available resources, it is critical to assess the health and economic gains being realized from increasingly large investments in ART. This study estimates total program costs and compares them with selected economic benefits of ART, for the current cohort of patients whose treatment is cofinanced by the Global Fund to Fight AIDS, Tuberculosis and Malaria. At end 2011, 3.5 million patients in low and middle income countries will be receiving ART through treatment programs cofinanced by the Global Fund. Using 2009 ART prices and program costs, we estimate that the discounted resource needs required for maintaining this cohort are $14.2 billion for the period 2011-2020. This investment is expected to save 18.5 million life-years and return $12 to $34 billion through increased labor productivity, averted orphan care, and deferred medical treatment for opportunistic infections and end-of-life care. Under alternative assumptions regarding the labor productivity effects of HIV infection, AIDS disease, and ART, the monetary benefits range from 81 percent to 287 percent of program costs over the same period. These results suggest that, in addition to the large health gains generated, the economic benefits of treatment will substantially offset, and likely exceed, program costs within 10 years of investment.

Critical choices in financing the response to the global HIV/AIDS pandemic

The AIDS pandemic will enter its fiftieth year in 2031. Despite much progress, there are thirty-three million infected people worldwide, and 2.3 million adults were newly infected in 2007. Without a change in approach, a major pandemic will still be with us in 2031. Modeling carried out for the AIDS 2031 project suggests that funding required for developing countries to address the pandemic could reach $35 billion annually by 2031-three times the current level. Even then, more than a million people will still be newly infected each year. However, wise policy choices focusing on high-impact prevention and efficient treatment could cut costs by half. Investments in new prevention tools and major behavior-change efforts are needed to spur more rapid advances. Existing donors, middle-income countries with contained epidemics, philanthropists, and innovative financing could help bridge the likely funding gap.

Improving health r&d financing for developing countries: a menu of innovative policy options

New drugs, vaccines, and diagnostics for the diseases of the developing world could save millions of lives and prevent enormous suffering and economic loss. Despite substantial new funding from the Gates Foundation and other donors, financing for the development of these new health technologies remains inadequate. New approaches are needed to generate more resources, make funding more stable and flexible, and further engage the expertise of the pharmaceutical industry. Several new financing mechanisms have been launched recently, and others are being proposed. This paper summarizes some of the most promising new ideas and offers a framework for evaluating them.

Fluorinated Heteroaromatic Polyethers for Low Dielectric Constant/High Temperature Applications

Synthesis and characterization of three classes of poly(arylene ether oxazole)s and poly(arylene ether thiazole)s with trifluoromethyl substituents in various positions is described. Based on these examples, the influence of the chemical structure of the polymers on properties such as glass transition temperature, solubility, and thermal stability will be discussed. Structural parameters studied are the number and nature of the heteroaromatic rings, the number and position of the trifluoromethyl groups, and the structure (flexibility, polarity) of various linking groups.

Financing of HIV/AIDS programme scale-up in low-income and middle-income countries, 2009-31

As the global HIV/AIDS pandemic nears the end of its third decade, the challenges of efficient mobilisation of funds and management of resources are increasingly prominent. The aids2031 project modelled long-term funding needs for HIV/AIDS in developing countries with a range of scenarios and substantial variation in costs: ranging from US$397 to $722 billion globally between 2009 and 2031, depending on policy choices adopted by governments and donors. We examine what these figures mean for individual developing countries, and estimate the proportion of HIV/AIDS funding that they and donors will provide. Scenarios for expanded HIV/AIDS prevention, treatment, and mitigation were analysed for 15 representative countries. We suggest that countries will move in increasingly divergent directions over the next 20 years; middle-income countries with a low burden of HIV/AIDS will gradually be able to take on the modest costs of their HIV/AIDS response, whereas low-income countries with a high burden of disease will remain reliant upon external support for their rapidly expanding costs. A small but important group of middle-income countries with a high prevalence of HIV/AIDS (eg, South Africa) form a third category, in which rapid scale-up in the short term, matched by outside funds, could be phased down within 10 years assuming strategic investments are made for prevention and efficiency gains are made in treatment.

STUDIES IN SENSITIZATION TO SKIN : I. THE PRODUCTION OF ANTIBODIES TO SKIN BY MEANS OF THE SYNERGISTIC ACTION OF HOMOLOGOUS SKIN ANTIGEN AND STAPHYLOCOCCUS TOXIN

1. Techniques for the preparation of skin antigen suitable for intramuscular injection in rabbits, and of skin antigens (autolysate) for serological experiments are described. 2. A method was evolved which produced a soluble skin antigen (autolysate) suitable for performing precipitin tests. 3. Injection of the rabbit skin antigen and of staphylococcus toxin in rabbits resulted in the formation of antibodies (precipitins) to homologous skin. 4. When homologous skin alone was injected into rabbits, the antibody formation was questionable, or at most, slight. 5. The injection of staphylococcus toxin alone resulted in antibody formation, this antibody being specific for the toxin and not reacting with broth. 6. By utilization of the synergistic action of staphylococcus toxin and of homologous skin antigen, it has been possible for the first time to produce specific antiskin antibodies in experimental animals.

Detection of HIV-1 in alternative specimen types using the APTIMA HIV-1 RNA Qualitative Assay

Peripheral blood mononuclear cells (PBMCs), saliva, seminal plasma, and dried blood spots were evaluated as specimen types for the APTIMA HIV-1 RNA Qualitative Assay (APTIMA HIV-1 Assay), which employs a target capture step to recover HIV-1-specific sequences from complex specimen types. Analytical sensitivity studies were carried out using samples that were either diluted or eluted with a buffered detergent and spiked with different concentrations of HIV-1 ranging from 1 to 10,000 copies/mL. PBMC samples spiked with HIV-1 had comparable analytical sensitivity to HIV-1 spiked plasma with a 95% limit of detection of 13.1 and 17.2 copies/mL, respectively. Analytical sensitivity in seminal plasma specimens diluted 1:5 and saliva diluted 1:2 was comparable to HIV-1 spiked dilution buffer alone. Whole blood and dried blood spot specimens spiked with HIV-1 had equivalent reactivity at 250 copies/spot (5000 copies/mL). However, the 95% limit of detection values were significantly different (293.7 copies/mL for whole blood and 2384 copies/mL for dried blood spot specimens). No significant effect on analytical sensitivity was observed when one HIV-1 positive dried blood spot punch was pooled with up to 9 HIV-1 negative dried blood spot punches. Together, these studies demonstrate that the APTIMA HIV-1 RNA Qualitative Assay can be used to process a diverse array of specimen types with minimal impact on analytical sensitivity for most specimen types.

Demand forecasting for preventive AIDS vaccines: economic and policy dimensions

BACKGROUND

An AIDS vaccine could play a very significant role in reversing the HIV pandemic, saving millions of lives. For a vaccine to have such an impact, it must be widely available and adopted and taken up rapidly in the countries most affected. A demand-forecasting model provides a valuable tool that can guide R&D spending decisions and identify policy actions to help achieve these goals.

OBJECTIVE

To identify the key determinants of vaccine demand, model global adoption and uptake dynamics, estimate potential demand and revenues associated with future preventive AIDS vaccines, and to conduct sensitivity analyses to assess the impact of each parameter on demand.

METHODS

A discrete, deterministic, linear, predictive mathematical model based on stratified population averages with a 30-year time horizon was developed to assess scenarios of future demand. This forecasting model was used to explore the effects of vaccine characteristics and a variety of regulatory, political, financial and health service factors on future demand and revenues. The intervention modelled was a preventive AIDS vaccine (efficacy: 30-90%; duration of protection: 3-5 years; in a two-dose prime-boost combination). The main outcome measure was the number of complete courses of vaccine administered.

RESULTS

The model suggests that demand for a preventive AIDS vaccine with a medium efficacy (50%) and duration of protection (3 years) would average 68 million courses annually over a 30-year period. Under different scenarios, demand would peak at 38-152 million courses annually. On the basis of tiered pricing across public and private markets ($US2-100 per dose), these levels of peak demand would translate into $US2.5-5.5 billion in peak annual sales revenues. Private markets and high-income countries account for small volumes but large shares of projected revenues, while low-income countries account for large volumes and more modest, but still significant, sales revenues. Vaccinations to 'catch-up' those who are missed or not eligible for routine annual programmes (whether adolescent or high-risk populations) would account for 20-35% of cumulative vaccination courses across all scenarios. Demand was found to be sensitive to vaccine efficacy, duration of protection and price. Efforts to expedite regulatory review processes, improve immunization infrastructure and reduce political constraints could increase demand for an AIDS vaccine by 40 million additional courses a year compared with the medium efficacy (baseline) vaccine forecast.

CONCLUSIONS

Our model can provide vaccine developers with credible estimates of market potential for an AIDS vaccine, and with a tool that can be used to improve forecasts over time as AIDS vaccine science progresses. It can also help governments to identify and pursue those policies that could best strengthen demand and uptake of a safe and effective preventive AIDS vaccine.

The impact of an AIDS vaccine in developing countries: a new model and initial results

A new model was developed to examine the potential impacts of an AIDS vaccine in developing countries. The findings suggest that even a modestly efficacious first-generation vaccine could have a profound effect on the AIDS pandemic. A vaccine with 50 percent efficacy provided to 30 percent of the population would reduce new annual infections by 34 percent (seventeen million infections avoided) over fifteen years and result in substantial financial savings. A more efficacious vaccine, combined with expanded delivery, would do even more to control the pandemic. It therefore makes sense to continue investing in AIDS vaccine research and development and the eventual manufacture and widespread distribution of a vaccine.

Multi-center phase II/III randomized controlled clinical trial using TNFerade combined with chemoradiation in patients with locally advanced pancreatic cancer (LAPC)

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Background: TNFerade is a replication-deficient adenoviral vector carrying the transgene for human TNF-a protein, regulated by the radiation-inducible promoter Egr-1. A 50 patient (pt) phase II dose-escalation study in LAPC showed a possible dose-dependent improvement in survival. To confirm these findings, the randomized Pancreatic Cancer Clinical Trial with TNFerade (PACT) study was developed. PACT is a 330 pt study, powered to detect a 20% absolute increase in the primary efficacy endpoint (overall survival at 1 year) compared to standard of care (SOC) chemoradiation. An interim analysis of safety and efficacy was planned after the first 51 pts were randomized. Survival data to 11/15/06 has been evaluated and are reported here. Methods: The TNFerade arm pts received a five- wk treatment of weekly injections of 4 x 1011 pu TNFerade, continuous infusion 5-FU (200 mg/m2/day x 5 days/wk) and 50.4 Gy radiation. TNFerade was administered by percutaneous CT-guided transabdominal injection. The SOC arm received the same regimen, without TNFerade injections. Patients were randomized 2:1 to the TNFerade and SOC arms. The first 51 randomized pts were assessed for evidence of objective response (OR) and overall survival Results: Assessment of response data is still ongoing. TNFerade + SOC was well tolerated. One year survival, the primary endpoint of the study, was 70.5% in the TNFerade + SOC arm versus 28.0% in the SOC arm, an absolute increase of 42.5%. The median survival for TNFerade + SOC pts was 515 days compared to 335 days for the SOC pts. The logrank statistic for comparison between the two arms is X2 = 2.014 (p=0.16). Conclusions: The interim survival data is preliminary. The magnitude of the difference in survival in favor of the TNFerade + SOC arm, however, is encouraging. The data appears to corroborate previous findings from the dose-escalation study, which showed an apparent survival advantage in the 4×1011 pu dose group compared to 4 x 109 pu group. A second interim analysis is planned with larger patient numbers to determine whether this early positive trend is confirmed.

No significant financial relationships to disclose.

Putting it together: AIDS and the millennium development goals

Failure to halt and reverse the HIV/AIDS epidemic, say the authors, will continue to jeopardize progress on achieving a wide range of the MDGs.

Estimating the demand for a preventive HIV vaccine: why we need to do better. Reliable estimates would help in achieving several policy and advocacy objectives

Additional research on public and private demand for HIV vaccines is needed to strengthen ongoing advocacy and planning for eventual vaccine introduction, say Hecht and Suraratdecha.

Anti-VEGF antibody bevacizumab (Avastin) with 5FU/LV as third line treatment for colorectal cancer

BACKGROUND

To evaluate the activity and safety of bevacizumab when given with standard 5FU/leukovorin (LV) regimens in patients with metastatic colorectal cancer who have failed irinotecan and oxaliplatin-based treatments.

METHODS

Bevacizumab was given at 5 mg/kg as an IV infusion every 2 weeks. Patients received 5FU according to Roswell Park or the de Gramont regimen.

RESULTS

Nineteen patients enrolled, median age 60, median PS: 1. Most common toxicity attributable to bevacizumab was mild hypertension, epistaxis and mild proteinuria; 1 patient had a CNS haemorrhage. The median number of cycles was 1 (8 weeks). Clinical benefit as disease stabilisation lasting 2-6 months was noted in 9 patients, whereas 10 progressed (median f/u: 5 months). TTP was 16 weeks, and the overall survival has not been reached (24+ weeks).

CONCLUSIONS

Bevacizumab may result in growth arrest and clinical benefit in a substantial proportion of patients with colorectal cancer and no alternative treatment.

[Waiting for the EuGH verdict to be put into practice or "Introduction of the four-day week on full pay"]

The submitted model of working time transposes and interprets german industrial law. The result of this interpretation is a high level of acceptance of the employees, a fast education that is high qualified with costs that are still affordable. The advantage of this model compared with the shift-model that runs after the EuGH-decision is obvious if you look at the reality of our health care system. This is why it is important to have an efficient interpretation of the existing law. Of course it will be a necessity also in the future to create new models of working time and to adapt these models in a way that it fits into the structure of a hospital. It would be the wrong way to force a juridical and political decision, how it was done by the german government that gave a deadline to put the EuGH decision into operation, without the possibility of an interpretation that fulfils the demand of the hospital.

Cell death during development of intercalated ducts in the rat submandibular gland

Programmed cell death, or apoptosis, occurs during the development of many tissues and organs in almost all multicellular organisms. Although apoptosis of salivary gland cells has been demonstrated in several pathological conditions, the role of apoptosis in the postnatal development of the salivary glands is unknown. We have studied the development of the rat submandibular gland (SMG) during its transition from the perinatal stage to the mature adult stage. Terminal tubule or Type I cells, which synthesize the secretory protein SMG-C, are prominent in the perinatal acini and are believed to form the intercalated ducts of the adult gland. Between 25 days and 30 days after birth, the number of Type I cells and their SMG-C immunoreactivity markedly decreased. Apoptotic cells in association with the developing intercalated ducts were labeled with the Terminal Deoxyribonucleotidyl Transferase-Mediated dUTP Nick End Labeling (TUNEL) method. Between 25 and 40 days of age, from 50 to 80% of the apoptotic cells in cryostat sections of the SMG were closely associated with the intercalated ducts. Electron microscopy showed that the Type I cells became vacuolated, their secretory granules were reduced in size and number, and the amount of rough endoplasmic reticulum was decreased. Cellular debris resembling apoptotic bodies was phagocytosed by macrophages and adjacent intercalated duct cells. These observations suggest that the loss of Type I cells and reduction of SMG-C immunoreactivity during development of the intercalated ducts of the adult rat SMG is due, at least in part, to apoptosis.

Efficacy of exogenous recombinant murine leptin in lean and obese 10- to 12-mo-old female CD-1 mice

Leptin efficacy was compared in obese and lean female CD-1 mice. Body weights in these 10- to 12-mo-old mice ranged from 29.7 to 62.0 g, and leptin levels correlated with body weight. Mice from the lean and obese ends of the weight distribution were treated with daily peripheral leptin injections (1-100 mg/kg) for a 33-day period. The half-maximal effective doses for weight loss and fat reduction were shifted 0.5-0.7 log to the right for obese mice. Leptin was less efficacious at low doses (1-3 mg/kg) in obese mice but equal to or more efficacious in obese than lean mice at high doses (30-100 mg/kg). Leptin's initial effects on weight loss could be explained by appetite suppression in both groups, but its effects on fat reduction were greater in leptin-treated than pair-fed mice, particularly in the lean group. Leptin also prevented the elevations in serum corticosterone and ketones found in pair-fed lean mice. These data allow a quantitative comparison of leptin sensitivity in obese vs. lean CD-1 mice and suggest that in mice where obesity is a function of outbreeding and age, leptin sensitivity is moderately reduced. Furthermore, although appetite suppression has a clear role in leptin's effects on body weight, leptin may also have specific effects on lipid metabolism and mobilization that are different from the metabolic compensations that normally occur with food deprivation.

An improved intravital microscopy system

The use of intravital microscopy as a tool for studying the microcirculation has increased greatly over the last several decades. Early microscopes provided the first pictures of the microcirculation, but were cumbersome to use and subjected the tissue to a high light intensity, a problem which has recently become the subject of much discussion. The goal of this project was therefore to build a more ergodynamic microscope which minimizes the light exposure to the tissue. The automation of the microscope controls provides a platform on which other options can be built into the microscope, such as an autofocus feature. Furthermore, the use of the Optimas software also opens the possibility for on-line data processing.

Autocatalytic networks with intermediates. I: Irreversible reactions

A class of autocatalytic reaction networks based on template-dependent replication and specific catalysis is considered. Trimolecular "elementary steps" of simple replicator dynamics are resolved into two consecutive irreversible reactions. The extreme cases, competition for common resources and hypercycle-like cooperative feedback, were analyzed in some detail. Although the dynamics of the extended networks resembles corresponding replicator dynamics in general, there are significant differences. Most notably, the interior fixed points in the cooperative model turned out to be asymptotically stable for an arbitrary number of species, whereas simple replicator dynamic predicts an asymptotically stable periodic orbit fixed for four species and fewer and a stable periodic orbit for all other cases.

Refined crystal structure and mutagenesis of human granulocyte-macrophage colony-stimulating factor

The crystal structure of recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) has been refined against data extending to a resolution of approximately 2.4 A along a* and approximately 1.9 A along b* and c*. Anisotropic scale factors of B11 = -20.8 A2, B22 = 7.4 A2, B33 = 13.3 A2 corrected for the more rapid fall of diffraction in the a* direction. The anisotropy correlates with the weak crystal packing interactions along the a axis. In addition to apolar side chains in the protein core, there are 10 buried hydrogen bonding residues. Those residues involved in intramolecular hydrogen bonding to main chain atoms are better conserved than those hydrogen bonding to other side chain atoms; 24 solvation sites are observed at equivalent positions in the two molecules in the asymmetric unit, and the strongest among these are located in clefts between secondary structural elements. No buried water sites are seen. Two surface clusters of hydrophobic side chains are located near the expected receptor binding regions. Mutagenesis of 11 residues on the helix A/helix C face confirms the importance of Glu-21 and shows that Gly-75 and Gln-86, located on helix C, each cause a greater than fourfold drop in activity. Glu-21 and Gly-75, but not Gln-86, are structurally equivalent to residues involved in the growth hormone binding to its receptor.