Outcomes and care quality metrics for people living with rheumatic heart disease and atrial fibrillation in Uganda

Background

Atrial fibrillation (AF) is a common complication of rheumatic heart disease (RHD) and is challenging to treat in lower-resourced settings in which RHD remains endemic.

Objective

We characterized demographics, treatment outcomes, and factors leading to care retention for participants with RHD and AF in Uganda.

Methods

We conducted a retrospective analysis of the Uganda national RHD registry between June 2009 and May 2018. Participants with AF or atrial flutter were included. Demographics, survival, and care metrics were compared with participants without AF. Multivariable logistic regression was used to identify factors associated with retention in care among participants with AF.

Results

A total of 1530 participants with RHD were analyzed and 293 (19%) had AF. The median age was 24 (interquartile range 14-38) years. Mortality was similar in both groups (adjusted hazard ratio 1.183, P = .77) over a median follow-up of 203 (interquartile range 98-275) days. A total of 79% of AF participants were prescribed anticoagulation, and 43% were aware of their target international normalized ratio. Retention in care was higher in participants with AF (18% vs 12%, P < .01). Factors associated with decreased retention in care include New York Heart Association functional class III/IV (adjusted odds ratio [OR] 0.48, 95% confidence interval [CI] 0.30-0.76) and distance to nearest health center (adjusted OR 0.94, 95% CI 0.90-0.99). Anticoagulation prescription was associated with enhanced care retention (adjusted OR 1.86, 95% CI 1.24-2.79).

Conclusion

Participants with RHD and AF in Uganda do not experience higher mortality than those without AF. Anticoagulation prescription rates are high. Although retention in care is poor among RHD participants, those with concurrent AF are more likely to be retained.

Clinical Profile and Outcomes of Rheumatic Heart Disease Patients Undergoing Surgical Valve Procedures in Uganda

Background

Chronic valvular heart disease is a well-known, long-term complication of acute rheumatic fever (ARF), which remains a major public health problem in low- and middle-income countries. Access to surgical management remains limited. Outcomes of the minority proportion of patients that access surgery have not been described in Uganda.

Objectives

To describe the volume and type of rheumatic heart disease (RHD) valvular interventions and the outcomes of operated patients in the Uganda RHD registry.

Methods

We performed a retrospective cohort study of all valve surgery procedures identified in the Uganda RHD registry through December 2021.

Results

Three hundred and sixty-seven surgical procedures were performed among 359 patients. More than half were among young (55.9% were ≤20 years of age), female (59.9%) patients. All patients were censored at 15 years. The median (IQR) follow up period was 43 (22,79) months. Nearly half of surgeries (46.9%) included interventions on multiple valves, and most valvular operations were replacements with mechanical prostheses (96.6%). Over 70% of the procedures were sponsored by charity organizations. The overall mortality of patients who underwent surgery was 13% (47/359), with over half of the mortalities occurring within the first year following surgery (27/47; 57.4%). Fifteen-year survival or freedom from re-operation was not significantly different between those receiving valve replacements and those receiving valve repair (log-rank p = 0.76).

Conclusions

There has been increasing access to valve surgery among Ugandan patients with RHD. Post-operative survival is similar to regionally reported rates. The growing cohort of patients living with prosthetic valves necessitates national expansion and decentralization of post-operative care services. Major reliance on charity funding of surgery is unsustainable, thus calling for locally generated and controlled support mechanisms such as a national health insurance scheme. The central illustration (Figure 1) provides a summary of our findings and recommendations.

Healthcare provider-targeted mobile applications to diagnose, screen, or monitor communicable diseases of public health importance in low- and middle-income countries: A systematic review

Communicable diseases remain a leading cause of death and disability in low- and middle-income countries (LMICs). mHealth technologies carry considerable promise for managing these disorders within resource-poor settings, but many existing applications exclusively represent digital versions of existing guidelines or clinical calculators, communication facilitators, or patient self-management tools. We thus systematically searched PubMed, Web of Science, and Cochrane Central for studies published between January 2007 and October 2019 involving technologies that were mobile phone- or tablet-based; able to screen for, diagnose, or monitor a communicable disease of importance in LMICs; and targeted health professionals as primary users. We excluded technologies that digitized existing paper-based tools or facilitated communication (i.e., knowledge-based algorithms). Extracted data included disease category, pathogen type, diagnostic method, intervention purpose, study/target population, sample size, study methodology, development stage, accessory requirement, country of development, operating system, and cost. Given the search timeline, studies involving COVID-19 were not included in the analysis. Of 13,262 studies identified by the screen, 33 met inclusion criteria. 12% were randomized clinical trials (RCTs), with 58% of publications representing technical descriptions. 62% of studies had 100 or fewer subjects. All studied technologies involved diagnosis or screening steps; none addressed the monitoring of infections. 52% focused on priority diseases (HIV, malaria, tuberculosis), but only 12% addressed a neglected tropical disease. Although most reported studies were priced under 20USD at time of publication, two thirds of the records did not yet specify a cost for the study technology. We conclude that there are only a small number of mHealth technologies focusing on innovative methods of screening and diagnosing communicable diseases potentially of use in LMICs. Rigorous RCTs, analyses with large sample size, and technologies assisting in the monitoring of diseases are needed.

Effectiveness of a community health worker-led low-sodium salt intervention to reduce blood pressure in rural Bangladesh: protocol for a cluster randomized controlled trial

BACKGROUND

High blood pressure is a major public health problem in low- and middle-income countries. Low-sodium salt substitute (LSSS) is a promising population-level blood pressure-lowering intervention requiring minimal behavioral change. The optimal method of delivering LSSS to individuals, however, is currently unknown. Community health workers (CHWs) have successfully been used to implement health interventions in Bangladesh and may provide a venue for the dissemination of LSSS.

METHODS

We aim to conduct a cluster-randomized controlled trial involving 309 households in rural Bangladesh previously identified and characterized by the BRAC James P Grant School of Public Health, BRAC University (BRAC JPGSPH). These households will be randomly assigned to three arms: (1) control, i.e., no intervention; (2) information only, i.e., community health workers will provide basic information on high blood pressure, the health consequences of excessive salt consumption, and feedback to the participant on the likely quantity of salt s/he consumes (estimated using a questionnaire); (3) free LSSS arm: the same information as in arm 2 will be provided, but participants will receive 6 months of free low-sodium salt along with education on the benefits of LSSS. One male and one female adult (age ≥ 18 years) in each household will be invited to participate, the exclusion criteria being households with members known to have high serum potassium levels, are taking medications known to elevate potassium levels (e.g., ACE inhibitors, ARBs, potassium-sparing diuretics), are already taking potassium supplements, or those who have known kidney disease or abnormal serum creatinine at baseline. The primary endpoint will be blood pressure at 6 months post-intervention.

DISCUSSION

Recent large clinical trials of LSSS in China and India have shown not only blood pressure improvements, but also stroke, major cardiac event, and all-cause mortality reductions. Nevertheless, how to best translate this intervention to population-level effectiveness remains unclear. Our study would test whether a community health worker-based program could be effectively used to disseminate LSSS and achieve measurable blood pressure benefits.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05425030. Registered on June 21, 2022.

Impact of a Multidisciplinary Curriculum Training Students and Residents in Tobacco Cessation Strategies for Adult Caregivers of Children

Introduction

Children's exposure to secondhand smoke is an underaddressed public health threat. The Clinical Effort Against Secondhand Smoke Exposure (CEASE) is a validated framework that trains pediatric providers to screen, counsel, refer to quitlines, and prescribe tobacco cessation medications to adult caregivers of children.

Methods

A physician champion at a major urban academic center delivered a longitudinal didactic curriculum of CEASE principles to medical and nurse practitioner students and pediatrics and family medicine residents. At the end of each session, participants completed an anonymous survey measuring changes in self-perceived knowledge, comfort, and familiarity with smoking cessation skills and concepts. Using a separate end-of-year questionnaire, we also surveyed a group of pediatric residents to compare the impact of CEASE training on clinical practice. Finally, we tracked the number of referrals to the state's quitline for the duration of the training.

Results

Fifty-two trainees (55% students, 45% residents) responded to the evaluation survey administered immediately following training. There were statistically significant improvements in median scores after CEASE training for comfort in screening, counseling, motivational interviewing, referring to smokers' helplines, and providing caregivers with nicotine replacement therapy (NRT) prescriptions. Fifty-one percent of pediatric residents (41 of 80) responded to the end-of-year survey, which showed statistically significant differences in the number of patients/caregivers offered a referral to California's quitline and prescription of NRT according to completion of CEASE training.

Discussion

CEASE training successfully improved the self-efficacy of health professions students and residents in smoking cessation techniques for adult caregivers of children.

What We Lost in the Fire: Endemic Tropical Heart Diseases in the Time of COVID-19

The COVID-19 pandemic has profoundly influenced the effort to achieve global health equity. This has been particularly the case for HIV/AIDS, tuberculosis, and malaria control initiatives in low- and middle-income countries, with significant outcome setbacks seen for the first time in decades. Lost in the calls for compensatory funding increases for such programs, however, is the plight of endemic tropical heart diseases, a group of disorders that includes rheumatic heart disease, Chagas disease, and endomyocardial fibrosis. Such endemic illnesses affect millions of people around the globe and remain a source of substantial mortality, morbidity, and health disparity. Unfortunately, these conditions were already neglected before the pandemic, and thus those living with them have disproportionately suffered during the time of COVID-19. In this perspective, we briefly define endemic tropical heart diseases, summarizing their prepandemic epidemiology, funding, and control statuses. We then describe the ways in which people living with these disorders, along with the healthcare providers and researchers working to improve their outcomes, have been harmed by the ongoing COVID-19 pandemic. We conclude by proposing the path forward, including approaches we may use to leverage lessons learned from the pandemic to strengthen care systems for these neglected diseases.

Impacts of a Multicenter Medical Education Curriculum for Training Pediatric Residents on Tobacco Cessation for Adult Caregivers of Pediatric Patients

The Clinical Effort Against Secondhand Smoke Exposure (CEASE) is an evidence-based framework that increases pediatric providers' ability to address secondhand smoke exposure of minors. Physician champions at 4 University of California sites conducted regular 1-hour didactic trainings on CEASE principles to pediatric residents as part of a longitudinal curriculum. At the conclusion of the academic year, 111 of 284 residents (39%) completed an anonymous survey. CEASE-trained residents reported significantly higher rates than untrained residents of counseling on smoking cessation (adjusted odds ratio [OR] = 4.50, P = .009), and referring to the smokers' quitline (adjusted OR 3.6, P = .007) to 50% or more of their patients' caregivers who smoked. In addition, among CEASE-trained residents, there were significant increases in multiple post-training knowledge and self-efficacy items. Our results show that a brief educational curriculum can be helpful in changing pediatric residents' attitudes and behavior toward assisting adult caregivers to pediatric patients in smoking cessation.

Functional Deimmunization of Botulinum Neurotoxin Protease Domain via Computationally Driven Library Design and Ultrahigh-Throughput Screening

Botulinum neurotoxin serotype A (BoNT/A) is a widely used cosmetic agent that also has diverse therapeutic applications; however, adverse antidrug immune responses and associated loss of efficacy have been reported in clinical uses. Here, we describe computational design and ultrahigh-throughput screening of a massive BoNT/A light-chain (BoNT/A-LC) library optimized for reduced T cell epitope content and thereby dampened immunogenicity. We developed a functional assay based on bacterial co-expression of BoNT/A-LC library members with a Förster resonance energy transfer (FRET) sensor for BoNT/A-LC enzymatic activity, and we employed high-speed fluorescence-activated cell sorting (FACS) to identify numerous computationally designed variants having wild-type-like enzyme kinetics. Many of these variants exhibited decreased immunogenicity in humanized HLA transgenic mice and manifested in vivo paralytic activity when incorporated into full-length toxin. One variant achieved near-wild-type paralytic potency and a 300% reduction in antidrug antibody response in vivo. Thus, we have achieved a striking level of BoNT/A-LC functional deimmunization by combining computational library design and ultrahigh-throughput screening. This strategy holds promise for deimmunizing other biologics with complex superstructures and mechanisms of action.

Association between Obesity and Length of COVID-19 Hospitalization: Unexpected Insights from the American Heart Association National COVID-19 Registry

Background

The mechanism for possible association between obesity and poor clinical outcomes from Coronavirus Disease 2019 (COVID-19) remains unclear.

Methods

We analyzed 22,915 adult COVID-19 patients hospitalized from March 2020 to April 2021 to non-intensive care using the American Heart Association National COVID Registry. A multivariable Poisson model adjusted for age, sex, medical history, admission respiratory status, hospitalization characteristics, and laboratory findings was used to calculate length of stay (LOS) as a function of body mass index (BMI). We similarly analyzed 5,327 patients admitted to intensive care for comparison.

Results

Relative to normal BMI subjects, overweight, class I obese, and class II obese patients had approximately half-day reductions in LOS (–0.469 days, P<0.01; –0.480 days, P<0.01; –0.578 days, P<0.01, respectively).

Conclusion

The model identified a dose-dependent, inverse relationship between BMI category and LOS for COVID-19, which was not seen when the model was applied to critically ill patients.

Aging Hearts in a Hotter, More Turbulent World: The Impacts of Climate Change on the Cardiovascular Health of Older Adults

PURPOSE OF REVIEW

Climate change has manifested itself in multiple environmental hazards to human health. Older adults and those living with cardiovascular diseases are particularly susceptible to poor outcomes due to unique social, economic, and physiologic vulnerabilities. This review aims to summarize those vulnerabilities and the resultant impacts of climate-mediated disasters on the heart health of the aging population.

RECENT FINDINGS

Analyses incorporating a wide variety of environmental data sources have identified increases in cardiovascular risk factors, hospitalizations, and mortality from intensified air pollution, wildfires, heat waves, extreme weather events, rising sea levels, and pandemic disease. Older adults, especially those of low socioeconomic status or belonging to ethnic minority groups, bear a disproportionate health burden from these hazards. The worldwide trends responsible for global warming continue to worsen climate change-mediated natural disasters. As such, additional investigation will be necessary to develop personal and policy-level interventions to protect the cardiovascular wellbeing of our aging population.

N-Terminal Pro-B-Type Natriuretic Peptide as a Biomarker for the Severity and Outcomes With COVID-19 in a Nationwide Hospitalized Cohort

Background

Currently, there is limited research on the prognostic value of NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide) as a biomarker in COVID‐19. We proposed the a priori hypothesis that an elevated NT‐proBNP concentration at admission is associated with increased in‐hospital mortality.

Methods and Results

In this prospective, observational cohort study of the American Heart Association’s COVID‐19 Cardiovascular Disease Registry, 4675 patients hospitalized with COVID‐19 were divided into normal and elevated NT‐proBNP cohorts by standard age‐adjusted heart failure thresholds, as well as separated by quintiles. Patients with elevated NT‐proBNP (n=1344; 28.7%) were older, with more cardiovascular risk factors, and had a significantly higher rate of in‐hospital mortality (37% versus 16%; P<0.001) and shorter median time to death (7 versus 9 days; P<0.001) than those with normal values. Analysis by quintile of NT‐proBNP revealed a steep graded relationship with mortality (7.1%–40.2%; P<0.001). NT‐proBNP was also associated with major adverse cardiac events, intensive care unit admission, intubation, shock, and cardiac arrest (P<0.001 for each). In subgroup analyses, NT‐proBNP, but not prior heart failure, was associated with increased risk of in‐hospital mortality. Adjusting for cardiovascular risk factors with presenting vital signs, an elevated NT‐proBNP was associated with 2‐fold higher adjusted odds of death (adjusted odds ratio [OR], 2.23; 95% CI, 1.80–2.76), and the log‐transformed NT‐proBNP with other biomarkers projected a 21% increased risk of death for each 2‐fold increase (adjusted OR, 1.21; 95% CI, 1.08–1.34).

Conclusions

Elevated NT‐proBNP levels on admission for COVID‐19 are associated with an increased risk of in‐hospital mortality and other complications in patients with and without heart failure.

Preoperative Computed Tomography Angiography Reveals Leaflet-Specific Calcification and Excursion Patterns in Aortic Stenosis

BACKGROUND

Computed tomography-based evaluation of aortic stenosis (AS) by calcium scoring does not consider interleaflet differences in leaflet characteristics. Here, we sought to examine the functional implications of these differences.

METHODS

We retrospectively reviewed the computed tomography angiograms of 200 male patients with degenerative calcific AS undergoing transcatheter aortic valve replacement and 20 male patients with normal aortic valves. We compared the computed tomography angiography (CTA)-derived aortic valve leaflet calcification load (AVLCCTA), appearance, and systolic leaflet excursion (LEsys) of individual leaflets. We performed computer simulations of normal valves to investigate how interleaflet differences in LEsys affect aortic valve area. We used linear regression to identify predictors of leaflet-specific calcification in patients with AS.

RESULTS

In patients with AS, the noncoronary cusp (NCC) carried the greatest AVLCCTA (365.9 [237.3-595.4] Agatston unit), compared to the left coronary cusp (LCC, 278.5 [169.2-478.8] Agatston unit) and the right coronary cusp (RCC, 240.6 [137.3-439.0] Agatston unit; both P<0.001). However, LCC conferred the least LEsys (42.8° [38.8°-49.0°]) compared to NCC (44.8° [41.1°-49.78°], P=0.001) and RCC (47.7° [42.0°-52.3°], P<0.001) and was more often characterized as predominantly thickened (23.5%) compared to NCC (12.5%) and RCC (16.5%). Computer simulations of normal valves revealed greater reductions in aortic valve area following closures of NCC (-32.2 [-38.4 to -25.8]%) and RCC (-35.7 [-40.2 to -32.9]%) than LCC (-24.5 [-28.5 to -18.3]%; both P<0.001). By linear regression, the AVLCCTA of NCC and RCC, but not LCC, predicted LEsys (both P<0.001) in patients with AS. Both ostial occlusion and ostial height of the right coronary artery predicted AVLCCTA, RCC (P=0.005 and P=0.001).

CONCLUSIONS

In male patients, the AVLCCTA of NCC and RCC contribute more to AS than that of LCC. LCC's propensity for noncalcific leaflet thickening and worse LEsys, however, should not be underestimated when using calcium scores to assess AS severity.

Health system and patient-level factors serving as facilitators and barriers to rheumatic heart disease care in Sudan

BACKGROUND

Rheumatic heart disease (RHD) remains a leading cause of morbidity and mortality in Sub-Saharan Africa despite widely available preventive therapies such as prophylactic benzathine penicillin G (BPG). In this study, we sought to characterize facilitators and barriers to optimal RHD treatment with BPG in Sudan.

METHODS

We conducted a mixed-methods study, collecting survey data from 397 patients who were enrolled in a national RHD registry between July and November 2017. The cross-sectional surveys included information on demographics, healthcare access, and patient perspectives on treatment barriers and facilitators. Factors associated with increased likelihood of RHD treatment adherence to prophylactic BPG were assessed by using adjusted logistic regression. These data were enhanced by focus group discussions with 20 participants, to further explore health system factors impacting RHD care.

RESULTS

Our quantitative analysis revealed that only 32% of the study cohort reported optimal prophylaxis adherence. Younger age, reduced primary RHD healthcare facility wait time, perception of adequate health facility staffing, increased treatment costs, and high patient knowledge about RHD were significantly associated with increased odds of treatment adherence. Qualitative data revealed significant barriers to RHD treatment arising from health services factors at the health system level, including lack of access due to inadequate healthcare staffing, lack of faith in local healthcare systems, poor ancillary services, and patient lack of understanding of disease. Facilitators of RHD treatment included strong interpersonal support.

CONCLUSIONS

Multiple patient and system-level barriers to RHD prophylaxis adherence were identified in Khartoum, Sudan. These included patient self-efficacy and participant perception of healthcare facility quality. Strengthening local health system infrastructure, while enhancing RHD patient education, may help to improve treatment adherence in this vulnerable population.

Clinical Outcomes, Echocardiographic Findings, and Care Quality Metrics for People Living with HIV and Rheumatic Heart Disease in Uganda

BACKGROUND

Rheumatic Heart Disease (RHD) affects 41 million people worldwide, mostly in low- and middle-income countries, where it is co-endemic with HIV. HIV is also a chronic inflammatory disorder associated with cardiovascular complications, yet the epidemiology of patients affected by both diseases is poorly understood.

METHODS

Utilizing the Uganda National RHD Registry, we described the echocardiographic findings, clinical characteristics, medication prescription rates, and outcomes of all 73 people carrying concurrent diagnoses of HIV and RHD between 2009 and 2018. These individuals were compared to an age- and sex-matched cohort of 365 subjects with RHD only.

RESULTS

The median age of the HIV-RHD group was 36 years (IQR 15) and 86% were women. The HIV-RHD cohort had higher rates of prior stroke/transient ischemic attack (12% vs 5%, p=0.02) than the RHD-only group, with this association persisting following multivariable adjustment (OR 3.08, p=0.03). Prevalence of other comorbidities, echocardiographic findings, prophylactic penicillin prescription rates, retention in clinical care, and mortality were similar between the two groups.

CONCLUSIONS

Patients living with RHD and HIV in Uganda are a relatively young, predominantly female group. Although RHD-HIV comorbid individuals have higher rates of stroke, their similar all-cause mortality and RHD care quality metrics (such as retention in care) compared to those with RHD alone suggest rheumatic heart disease defines their clinical outcome more than HIV does. We believe this study to be one of the first reports of the epidemiologic profile and longitudinal outcomes of patients who carry diagnoses of both conditions.

Characterization of dermatological diagnoses among hospitalized patients experiencing homelessness

While previous studies have characterized the types of dermatological disease among people experiencing homelessness (PEH) in the outpatient setting, dermatological disease among hospitalized PEH has never been evaluated. Therefore, we performed a cross-sectional analysis of hospitalized patients who received dermatology consultations at two San Francisco hospitals between March 2018 and March 2020 and compared the odds of diagnostic categories between PEH and patients with stable housing. In both unadjusted and adjusted analyses, PEH had significantly higher odds of bacterial skin infections [adjusted odds ratio (aOR) = 2.29, 95% CI 1.46-3.61], ectoparasitic disease (aOR = 9.43, 95% CI 3.79-23.47), psoriasis or seborrhoeic dermatitis (aOR = 2.50, 95% CI 1.43-4.36) and venous stasis or lymphoedema (aOR = 2.54, 95% CI 1.23-5.27) and significantly lower odds of drug reactions (aOR = 0.34, 95% CI 0.18-0.67). Overall, these findings highlight the unique dermatological challenges among hospitalized PEH and suggest potential strategies to facilitate equitable dermatology care delivery.

The impact of novel coronavirus COVID-19 on noncommunicable disease patients and health systems: a review

Coronavirus disease 2019 (COVID-19) is an ongoing global pandemic affecting all levels of health systems. This includes the care of patients with noncommunicable diseases (NCDs) who bear a disproportionate burden of both COVID-19 itself and the public health measures enacted to combat it. In this review, we summarize major COVID-19-related considerations for NCD patients and their care providers, focusing on cardiovascular, pulmonary, renal, haematologic, oncologic, traumatic, obstetric/gynaecologic, operative, psychiatric, rheumatologic/immunologic, neurologic, gastrointestinal, ophthalmologic and endocrine disorders. Additionally, we offer a general framework for categorizing the pandemic's disruptions by disease-specific factors, direct health system factors and indirect health system factors. We also provide references to major NCD medical specialty professional society statements and guidelines on COVID-19. COVID-19 and its control policies have already resulted in major disruptions to the screening, treatment and surveillance of NCD patients. In addition, it differentially impacts those with pre-existing NCDs and may lead to de novo NCD sequelae. Likely, there will be long-term effects from this pandemic that will continue to affect practitioners and patients in this field for years to come.

Outcomes and Care Quality Metrics for Women of Reproductive Age Living With Rheumatic Heart Disease in Uganda

Background Rheumatic heart disease disproportionately affects women of reproductive age, as it increases the risk of cardiovascular complications and death during pregnancy and childbirth. In sub-Saharan Africa, clinical outcomes and adherence to guideline-based therapies are not well characterized for this population. Methods and Results In a retrospective cohort study of the Uganda rheumatic heart disease registry between June 2009 and May 2018, we used multivariable regression and Cox proportional hazards models to compare comorbidities, mortality, anticoagulation use, and treatment cascade metrics among women versus men aged 15 to 44 with clinical rheumatic heart disease. We included 575 women and 252 men with a median age of 27 years. Twenty percent had New York Heart Association Class III-IV heart failure. Among patients who had an indication for anticoagulation, women were less likely than men to receive a prescription of warfarin (66% versus 81%; adjusted odds ratio, 0.37; 95% CI, 0.14-0.96). Retention in care (defined as a clinic visit within the preceding year) was poor among both sexes in this age group (27% for men, 24% for women), but penicillin adherence rates were high among those retained (89% for men, 92% for women). Mortality was higher in men than women (26% versus 19% over a median follow-up of 2.7 years; adjusted hazard ratio, 1.66; 95% CI, 1.18-2.33). Conclusions Compared with men, women of reproductive age with rheumatic heart disease in Uganda have lower rates of appropriate anticoagulant prescription but also lower mortality rates. Retention in care is poor among both men and women in this age range, representing a key target for improvement.

Breast cancer induces systemic immune changes on cytokine signaling in peripheral blood monocytes and lymphocytes

Background

It is increasingly recognized that cancer progression induces systemic immune changes in the host. Alterations in number and function of immune cells have been identified in cancer patients’ peripheral blood and lymphoid organs. Recently, we found dysregulated cytokine signaling in peripheral blood T cells from breast cancer (BC) patients, even those with localized disease.

Methods

We used phosphoflow cytometry to determine the clinical significance of cytokine signaling responsiveness in peripheral blood monocytes from non-metastatic BC patients at diagnosis. We also examined the correlation between cytokine signaling in peripheral monocytes and the number of tumor-infiltrating macrophages in paired breast tumors.

Findings

Our results show that cytokine (IFNγ) signaling may also be dysregulated in peripheral blood monocytes at diagnosis, specifically in BC patients who later relapsed. Some patients exhibited concurrent cytokine signaling defects in monocytes and lymphocytes at diagnosis, which predict the risk of future relapse in two independent cohorts of BC patients. Moreover, IFNγ signaling negatively correlates with expression of CSF1R on monocytes, thus modulating their ability to infiltrate into tumors.

Interpretation

Our results demonstrate that tumor-induced systemic immune changes are evident in peripheral blood immune cells for both myeloid and lymphoid lineages, and point to cytokine signaling responsiveness as important biomarkers to evaluate the overall immune status of BC patients.

Funding

This study was supported by the Department of Defense Breast Cancer Research Program (BCRP), The V Foundation, Stand Up to Cancer (SU2C), and Breast Cancer Research Foundation (BCRF).

Patient and facility variation in costs of catheter ablation for atrial fibrillation

BACKGROUND

Cost-effectiveness or value of cardiovascular therapies may be undermined by unwarranted cost variation, particularly for heterogeneous procedures such as catheter ablation for atrial fibrillation (AF). We sought to characterize cost variation of AF ablation in the US healthcare system and the relationship between cost and outcomes.

METHODS AND RESULTS

We performed a retrospective cohort study using data from the MarketScan® commercial claims and Medicare supplemental databases including patients who received an AF ablation from 2007 to 2011. We aggregated encounter cost, reflecting total payments received for the encounter, to the facility level to calculate median facility cost. We classified procedures as outpatient or inpatient and assessed for association between cost and 30-day and 1-year outcomes. The analysis cohort included 9,415 AF ablations (59±11 years; 28% female; 52% outpatient) occurring at 327 facilities, with large cost variation across facilities (median: $25,100; 25th percentile: $18,900, 75th percentile: $35,600, 95th percentile: $57,800). Among outpatient procedures, there was reduced healthcare utilization in higher cost quintiles with reductions in rehospitalization at 30-days (Quintile 1: 16.1%, Quintile 5: 8.8%, P < 0.001) and 1-year (Quintile 1: 34.8%, Quintile 5: 25.6%, P < 0.001), which remained significant in multivariate analysis.

CONCLUSIONS

Although median costs of AF ablation are below amounts used in prior cost-effectiveness studies that demonstrated good value, large facility variation in cost suggests opportunities for cost reduction. However, for outpatient encounters, association of cost to modestly improved outcomes suggests cost containment strategies could have variable effects.

Motivations of women in Uganda living with rheumatic heart disease: A mixed methods study of experiences in stigma, childbearing, anticoagulation, and contraception

Background

Rheumatic heart disease (RHD) is a leading cause of premature mortality in low- and middle-income countries (LMICs). Women of reproductive age are a unique and vulnerable group of RHD patients, due to increased risk of cardiovascular complications and death during pregnancy. Yet, less than 5% of women of childbearing age with RHD in LMICs use contraceptives, and one in five pregnant women with RHD take warfarin despite known teratogenicity. It is unclear whether this suboptimal contraception and anticoagulant use during pregnancy is due to lack of health system resources, limited health literacy, or social pressure to bear children.

Methods

We conducted a mixed methods study of 75 women living with RHD in Uganda. Questionnaires were administered to 50 patients. Transcripts from three focus groups with 25 participants were analyzed using qualitative description methodology.

Results

Several themes emerged from the focus groups, including pregnancy as a calculated risk; misconceptions about side-effects of contraceptives and anticoagulation; reproductive decision-making control by male partners, in-laws, or physicians; abandonment of patients by male partners; and considerable stigma against heart disease patients for both their reproductive and financial limitations (often worse than that directed against HIV patients). All questionnaire respondents were told by physicians that their hearts were not strong enough to support a pregnancy. Only 14% used contraception while taking warfarin. All participants felt that society would look poorly on a woman who cannot have children due to a heart condition.

Conclusions

To our knowledge, this is the first qualitative study of female RHD patients and their attitudes toward cardiovascular disorders and reproduction. Our results suggest that health programs targeting heart disease in LMICs must pay special attention to the needs of women of childbearing age. There are opportunities for improved family/societal education programs and community engagement, leading to better outcomes and patient empowerment.

IL6 Signaling in Peripheral Blood T Cells Predicts Clinical Outcome in Breast Cancer

IL6 is a pleiotropic cytokine with both pro- and anti-inflammatory properties, which acts directly on cancer cells to promote their survival and proliferation. Elevated serum IL6 levels negatively correlate with survival of cancer patients, which is generally attributed to the direct effects of IL6 on cancer cells. How IL6 modulates the host immune response in cancer patients is unclear. Here, we show the IL6 signaling response in peripheral blood T cells is impaired in breast cancer patients and is associated with blunted Th17 differentiation. The mechanism identified involved downregulation of gp130 and IL6Rα in breast cancer patients and was independent of plasma IL6 levels. Importantly, defective IL6 signaling in peripheral blood T cells at diagnosis correlated with worse relapse-free survival. These results indicate that intact IL6 signaling in T cells is important for controlling cancer progression. Furthermore, they highlight a potential for IL6 signaling response in peripheral blood T cells at diagnosis as a predictive biomarker for clinical outcome of breast cancer patients. Cancer Res; 77(5); 1119-26. ©2016 AACR.

Evaluating the Cost-effectiveness of Catheter Ablation of Atrial Fibrillation

Atrial fibrillation (AF) is one of the most common cardiac conditions treated in primary care and specialty cardiology settings, and is associated with considerable morbidity, mortality and cost. Catheter ablation, typically by electrically isolating the pulmonary veins and surrounding tissue, is more effective at maintaining sinus rhythm than conventional antiarrhythmic drug therapy and is now recommended as first-line therapy. From a value standpoint, the cost-effectiveness of ablation must incorporate the upfront procedural costs and risks with the benefits of longer term improvements in quality of life (QOL) and healthcare utilisation. Here, we present a primer on cost-effectiveness analysis (CEA), review the data on cost-effectiveness of AF ablation and outline key areas for further investigation.

Spatial organization of dendritic cells within tumor draining lymph nodes impacts clinical outcome in breast cancer patients

BACKGROUND

Dendritic cells (DCs) are important mediators of anti-tumor immune responses. We hypothesized that an in-depth analysis of dendritic cells and their spatial relationships to each other as well as to other immune cells within tumor draining lymph nodes (TDLNs) could provide a better understanding of immune function and dysregulation in cancer.

METHODS

We analyzed immune cells within TDLNs from 59 breast cancer patients with at least 5 years of clinical follow-up using immunohistochemical staining with a novel quantitative image analysis system. We developed algorithms to analyze spatial distribution patterns of immune cells in cancer versus healthy intra-mammary lymph nodes (HLNs) to derive information about possible mechanisms underlying immune-dysregulation in breast cancer. We used the non-parametric Mann-Whitney test for inter-group comparisons, Wilcoxon Matched-Pairs Signed Ranks test for intra-group comparisons and log-rank (Mantel-Cox) test for Kaplan Maier analyses.

RESULTS

Degree of clustering of DCs (in terms of spatial proximity of the cells to each other) was reduced in TDLNs compared to HLNs. While there were more numerous DC clusters in TDLNs compared to HLNs,DC clusters within TDLNs tended to have fewer member DCs and also consisted of fewer cells displaying the DC maturity marker CD83. The average number of T cells within a standardized radius of a clustered DC was increased compared to that of an unclustered DC, suggesting that DC clustering was associated with T cell interaction. Furthermore, the number of T cells within the radius of a clustered DC was reduced in tumor-positive TDLNs compared to HLNs. Importantly, clinical outcome analysis revealed that DC clustering in tumor-positive TDLNs correlated with the duration of disease-free survival in breast cancer patients.

CONCLUSIONS

These findings are the first to describe the spatial organization of DCs within TDLNs and their association with survival outcome. In addition, we characterized specific changes in number, size, maturity, and T cell co-localization of such clusters. Strategies to enhance DC function in-vivo, including maturation and clustering, may provide additional tools for developing more efficacious DC cancer vaccines.

Center-surround vs. distance-independent lateral connectivity in the olfactory bulb

Lateral neuronal interactions are known to play important roles in sensory information processing. A center-on surround-off local circuit arrangement has been shown to play a role in mediating contrast enhancement in the visual, auditory, and somatosensory systems. The lateral connectivity and the influence of those connections have been less clear for the olfactory system. A critical question is whether the synaptic connections between the primary projection neurons, mitral and tufted (M/T) cells, and their main inhibitory interneurons, the granule cells (GCs), can support a center-surround motif. Here, we study this question by injecting a “center” in the glomerular layer of the olfactory bulb (OB) with a marker of synaptic connectivity, the pseudorabies virus (PRV), then examines the distribution of labeling in the “surround” of GCs. We use a novel method to score the degree to which the data fits a center-surround model vs. distance-independent connectivity. Data from 22 injections show that M/T cells generally form lateral connections with GCs in patterns that lie between the two extremes.

Learning to live together: harnessing regulatory T cells to induce organ transplant tolerance

The discovery of immune cells with regulatory effects has created considerable excitement for their potential use in inducing tolerance to transplanted tissues. Despite the fact that these cells possess essential functions in vivo, attempts to translate them into effective clinical therapies has proved challenging due to a number of unanticipated complexities in their behavior. This article provides a broad summary of research done to understand the largest of the regulatory cell subtypes, namely CD4+Foxp3+ Regulatory T cells (T(Regs)). Special attention will be paid to current and future difficulties in using T(Regs) clinically, as well as room for improvement and innovation in this field.

Lateral Connectivity in the Olfactory Bulb is Sparse and Segregated

Lateral connections in the olfactory bulb were previously thought to be organized for center–surround inhibition. However, recent anatomical and physiological studies showed sparse and distributed interactions of inhibitory granule cells (GCs) which tended to be organized in columnar clusters. Little is known about how these distributed clusters are interconnected. In this study, we use transsynaptic tracing viruses bearing green or red fluorescent proteins to further elucidate mitral- and tufted-to-GC connectivity. Separate sites in the glomerular layer were injected with each virus. Columns with labeling from both viruses after transsynaptic spread show sparse red or green GCs which tended to be segregated. However, there was a higher incidence of co-labeled cells than chance would predict. Similar segregation of labeling is observed from dual injections into olfactory cortex. Collectively, these results suggest that neighboring mitral and tufted cells receive inhibitory inputs from segregated subsets of GCs, enabling inhibition of a center by specific and discontinuous lateral elements.

Comparison of clinical with pathological nodal staging from systematic mediastinal lymph node dissection in early resectable non-small cell lung cancer

INTRODUCTION

We compared the accuracy of clinical nodal (cN) status N0-1 with that of pathological nodal (pN) status obtained from systematic mediastinal lymph node dissection (SMLD) in primary non-small cell lung cancer.

METHODS

Data from 22 consecutive patients, who underwent lung cancer resection and SMLD of at least three mediastinal lymph node stations, from November 2001 to May 2003, were ana1ysed retrospectively. Only patients with cN0-1 status on computed tomography (CT) referred for surgery, were included in this study.

RESULTS

Mean age of patients was 66.6 +/- 8.1 years with a male to female ratio of 17:5. Mean number of lymph node stations dissected was 5.8 +/- 1.8. 41 percent had squamous cell carcinoma, 45.5 percent had adenocarcinoma, and 4.5 percent each had large cell carcinoma, bronchioalveolar carcinoma or a lymphoepithelial carcinoma. pN2 metastases were found in 27.3 percent of patients. The sensitivity of cN0-1 was only 12.5 percent, with a specificity of 92.9 percent and an area under the receiver operating characteristics curve of 0.53. The positive and negative predictive values of cN0-1 status were 50 percent and 65 percent, respectively, with an accuracy of 59 percent. 41 percent of patients were understaged with 27.3 percent in pathological stage III. Curative resections were achieved in 59 percent of patients.

CONCLUSION

The sensitivity of cN0-1 status based on CT alone is extremely poor when compared with pN status from SMLD. Based on cN0-1 status alone without SMLD, 27.3 percent of patients in pN2 would have been understaged. We recommend that all patients with cN0-1 status should undergo SMLD of at least three appropriate mediastinal node stations, for more accurate staging.

Hypoxic preconditioning attenuated in kainic acid-induced neurotoxicity in rat hippocampus

The neuroprotective effect of hypoxic preconditioning on kainate (KA)-induced neurotoxicity, including apoptosis and necrosis, was investigated in rat hippocampus. Female Wistar-Kyoto rats were subjected to 380 mm Hg in an altitude chamber for 15 h/day for 28 days. Intrahippocampal infusion of KA was performed in chloral hydrate anesthetized rats, which acutely elevated 2,3-dihydroxybenzoic acid levels in normoxic rats. Seven days after the infusion, KA increased lipid peroxidation in the infused hippocampus and resulted in hippocampal CA3 neuronal loss. A 4-week hypoxic preconditioning attenuated KA-induced elevation in hydroxyl radical formation and lipid peroxidation as well as KA-induced neuronal loss. The effects of hypoxic preconditioning on KA-induced apoptosis and necrosis were investigated further. Two hours after KA infusion, cytosolic cytochrome c content was increased in the infused hippocampus. Twenty-four hours after KA infusion, pyknotic nuclei, cellular shrinkage, and cytoplasmic disintegration, but not TUNEL-positive staining, were observed in the CA3 region of hippocampus. Forty-eight hours after KA infusion, both DNA smear and DNA fragmentation were demonstrated in the infused hippocampus. Furthermore, TUNEL-positive cells, indicative of apoptosis, in the infused hippocampus were detected 72 h after KA infusion. Hypoxic pretreatment significantly reduced necrotic-like events in the KA-infused hippocampus. Moreover, hypoxic preconditioning attenuated apoptosis induced by KA infusion, including elevation in cytosolic cytochrome c content, TUNEL-positive cells, and DNA fragmentation. Our data suggest that hypoxic preconditioning may exert its neuroprotection of KA-induced oxidative injuries via attenuating both apoptosis and necrosis in rat hippocampus.

Involvement of noradrenergic innervation from locus coeruleus to hippocampal formation in negative feedback regulation of penile erection in the rat

We demonstrated previously that a novel negative feed back mechanism for the regulation of penile erection, which is triggered by ascending sensory inputs initiated by tumescence of the penis, exists in the hippocampal formation (HF). This study further elucidated the role of the locus coeruleus (LC), which is the largest aggregate of norepinephrine-containing neurons in the brain and provides the major noradrenergic innervation to the HF, in this process. Adult male Sprague-Dawley rats that were anesthetized and maintained with chloral hydrate were used. The intracavernous pressure (ICP) recorded from the corpus cavernosum of the penis was used as the experimental index for penile erection. Electrical activation of the LC elicited a significant reduction in baseline ICP. Similar observations were obtained on microinjection bilaterally into the hippocampal CA1 or CA3 subfield or dentate gyrus of equimolar doses (5 nmol) of norepinephrine (alpha1-, alpha2-agonist), phenylephrine (alpha1-agonist), or BHT 933 (alpha2-agonist). Bilateral electrolytic lesions of the LC discernibly enhanced the magnitude and/or duration of the elevation in ICP induced by intracavernous administration of papaverine (400 microgram). A potentiation of the papaverine-evoked ICP increase was also observed following pretreatment with bilateral hippocampal application of equimolar doses (250 pmol) of either prazosin (alpha1-, alpha2B-, alpha2C-antagonist), naftopidil (alpha1A/D-antagonist), yohimbine (alpha2-antagonst), or rauwolscine (alpha2B-, alpha2C-antagonist). None of these antagonists, however, affected baseline ICP. These results suggest that noradrenergic innervation of the HF that originates from the LC may play an active role in negative feedback regulation of penile erection, engaging at least alpha1A/D-, alpha2B-, and alpha2C-adrenoceptors in the HF.

Engagement of inducible nitric oxide synthase at the rostral ventrolateral medulla during mevinphos intoxication in the rat

We evaluated the relationship between the toxicity induced by the organophosphate mevinphos (Mev) and inducible nitric oxide synthase (iNOS) in the rostral ventrolateral medulla (RVLM), the medullary origin of sympathetic neurogenic vasomotor tone. Adult Sprague-Dawley rats that were anesthetized and maintained with propofol were used. Laser scanning confocal microscopic analysis revealed colocalization of the M2 subtype of muscarinic receptors (M(2)R) and iNOS immunoreactivity in RVLM neurons. Comicroinjection bilaterally of Mev (10 nmol) and artificial cerebrospinal fluid (aCSF) into the RVLM elicited a progressive decline in systemic arterial pressure (SAP) and heart rate. This was accompanied during phase 1 Mev intoxication by an increase in the power density of the very high-frequency (VHF; 5-9 Hz), high-frequency (HF; 0.8-2.4 Hz), low-frequency (LF; 0.25- 0.8 Hz) and very low-frequency (VLF; 0-0.25 Hz) components of SAP signals. Phase 2 exhibited a reversal of the VHF and VLF power to control levels and a further reduction in the power density of both HF and LF components to below baseline. Hypotension and bradycardia promoted by Mev were significantly blunted on coadministration into the RVLM of the selective iNOS inhibitors S-methylisothiourea (250 pmol) or aminoguanidine (250 pmol). Not only was the augmented power density of HF and LF components during phase 1 Mev intoxication further enhanced, the reduced power of these two spectral components during phase 2 was appreciably antagonized. On the other hand, the temporal changes in VHF and VLF power were essentially the same as with coadministration of Mev and aCSF. We conclude that, as a cholinesterase inhibitor, Mev may induce toxicity via nitric oxide produced by iNOS on activation of the M(2)R by the accumulated acetylcholine in the RVLM.

Cardiotoxicity in signal transduction therapeutics: erbB2 antibodies and the heart

Cardiotoxicity is a common and potentially devastating side effect of antineoplastic drug therapy. This empiric observation is seen as paradoxical given that the cardiomyocyte is considered to be a terminally differentiated cell. Despite the fact that these cells do not divide after birth, adult cardiomyocytes may become "innocent bystander" targets of anticancer drugs designed to interfere with cell signaling pathways in rapidly proliferating cells. In breast cancer clinical trials, treatment with the erbB2 receptor antibody trastuzumab combined with anthracyclines has been associated with an increased risk for the development of cardiac pump failure. Trastuzumab/anthracycline cardiomyopathy may be the first clinically significant cardiotoxicity to emerge from signal transduction therapeutics. The erbB2 receptor tyrosine kinase is known to have a critical role in cardiac development. In addition, erbB2 is thought to participate in an important pathway for growth, repair, and survival of adult cardiomyocytes as part of a signaling network that involves neuregulins and the neuregulin receptor erbB4. However, erbB2 levels in the adult heart are low when compared with the levels found in erbB2-overexpressing breast cancer cells that are the intended targets of trastuzumab therapy. Thus, trastuzumab-associated cardiotoxicity must be explained by some alternative mechanism. After confirming that trastuzumab is capable of inducing tyrosine phosphorylation of the human cardiomyocyte erbB2 protein, a novel system for culturing human myocardium was developed in our laboratory. We used this system to study the effects of trastuzumab on human cardiomyocytes in vitro and observed trastuzumab-induced structural and functional changes in human cardiomyocytes that were at least partially reversible with the addition of recombinant neuregulins. The results obtained in these experiments support a direct action of trastuzumab on human cardiomyocytes. In addition, these data provide insight regarding potential molecular mechanisms. Most importantly, these data draw attention to the inherent risk of cardiotoxicity associated with a newly emerging class of antineoplastic drugs that interfere with signal transduction pathways.

Weekly paclitaxel in advanced non-small cell lung cancer

Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) is one of the most commonly used agents in treating patients with locally advanced and metastatic non-small cell lung cancer (NSCLC). It is usually given once every 3 weeks. We have evaluated paclitaxel given once per week for 3 weeks every 4 weeks for patients with recurrent or metastatic NSCLC. Two consecutive studies using weekly paclitaxel were performed. The first study was a dose-escalation study with paclitaxel beginning at 50 mg/m(2) days 1, 8, and 15 every 4 weeks. Subsequent dose escalation was performed with 10 mg/m(2) increments per week. The second phase II study used paclitaxel at 80 mg/m(2) days 1, 8, and 15 every 4 weeks. The phase I study showed that the maximum tolerated dose was 90 mg/m(2)/wk for 3 weeks with 1 week off. The efficacy and side effects of both phase I and II were quite similar; therefore, the results were combined. Seventeen patients were in the phase I and 30 patients in the phase II study. The mean age was 72 years. Twenty-three patients had Eastern Cooperative Oncology Group performance status of 2 and 16 patients had received prior chemotherapy. One complete and 13 partial responses were observed with response duration ranging from 1 to 18+ months. Overall response rate was 30% (95% confidence interval, 18.5% to 42%). Overall median survival was 184 days. Grade 3/4 neutropenia was 8.5%, grade 3/4 infections was 6.4%, and grade 2 peripheral neuropathy was also 6.4%. Hyperglycemia with random blood sugar levels greater than 250 mg/dL was 6.4% and grade 3 fatigue was 4.3%. In general, treatment was well tolerated. In the best prognostic group of 16 patients without prior chemotherapy and with performance status 0 to 1, the response rate was 37.5% with a 1-year survival rate of 44% and median survival of 305 days. Prior chemotherapy, poor performance status, age higher than 70 years, and male gender carried a worse prognosis. In both phase I and II studies we observed limited myelosuppression, peripheral neuropathy, and constitutional symptoms. Weekly paclitaxel, delivered at our schedule, is an active and well-tolerated regimen. The role of weekly paclitaxel in NSCLC should be better defined in future randomized studies.

Renal apoptosis parallels ceramide content after prolonged ureteral obstruction in the neonatal rat

Obstructive nephropathy, the primary cause of renal insufficiency in infants, is characterized by progressive renal apoptosis. Ceramide is a sphingolipid known to stimulate apoptosis in the kidney. We investigated the effects of unilateral ureteral obstruction (UUO) on endogenous renal ceramide content and apoptosis in neonatal and adult rats. Animals were subjected to UUO or sham operation on the first day of life and were studied 3-28 days later. Adult rats were similarly treated and then studied 3 or 14 days later. In additional neonatal rats, the obstruction was removed after 5 days, with study at 14 or 28 days. Renal ceramide content was measured by diacylglycerol kinase assay, and apoptosis was determined by the terminal deoxynucleotidyl transferase dUTP nick-end-labeling technique. Renal ceramide content was 50-fold higher in the 3-day neonatal compared with the adult kidney and 10-fold higher in the 7-day neonatal compared with the adult kidney, but there was no additional effect of UUO on ceramide content at these ages. However, after 14 or 28 days UUO in the neonate, renal ceramide was elevated compared with sham or intact opposite kidneys, and renal apoptosis was directly related to ceramide content (r = 0.99, P < 0.001). Moreover, renal ceramide was reduced by relief of obstruction (P < 0.05). There was less apoptosis in the obstructed kidney of the adult than the neonate, and UUO had no effect on ceramide content at 14 days in the adult. We conclude that prolonged UUO (at least 14 days duration) increases endogenous renal ceramide in the neonatal but not the adult rat. It is likely that this contributes to the prolonged renal apoptotic response of the neonatal obstructed kidney.

Vertical profiles of aerosol volume from high-spectral-resolution infrared transmission measurements. I. Methodology

The wavelength-dependent aerosol extinction in the 800-1250-cm(-1) region has been derived from ATMOS (atmospheric trace molecule spectroscopy) high-spectral-resolution IR transmission measurements. Using models of aerosol and cloud extinction, we have performed weighted nonlinear least-squares fitting to determine the aerosol-volume columns and vertical profiles of stratospheric sulfate aerosol and cirrus cloud volume. Modeled extinction by use of cold-temperature aerosol optical constants for a 70-80% sulfuric-acid-water solution shows good agreement with the measurements, and the derived aerosol volumes for a 1992 occultation are consistent with data from other experiments after the eruption of Mt. Pinatubo. The retrieved sulfuric acid aerosol-volume profiles are insensitive to the aerosol-size distribution and somewhat sensitive to the set of optical constants used. Data from the nonspherical cirrus extinction model agree well with a 1994 mid-latitude measurement indicating the presence of cirrus clouds at the tropopause.

Apoptosis parallels ceramide content in the developing rat kidney

Ceramide is emerging as an important hydrophobic sphingolipid involved in cell differentiation and apoptosis. Since apoptosis plays a significant role in cellular remodeling during renal morphogenesis, we measured ceramide content and apoptosis in the fetal (18 days gestation), neonatal (3, 7, and 14 days postnatal), and adult rat kidney. In addition, to determine whether developmental changes in ceramide content are tissue-specific, we compared renal ceramide content with that in lung and liver. Ceramide was measured by the diacylglycerol kinase assay, and apoptosis was determined by the TUNEL technique. Renal ceramide content fell over 100-fold from the fetus to the 7th postnatal day. Renal apoptosis paralleled ceramide content, with a greater than 300-fold decrease in apoptosis from fetal to adult life. Ceramide content of the lung and liver was significantly less than that of the kidney, and changed less with maturation. We conclude that maturational changes in ceramide content are tissue-specific, and that the high rate of apoptosis in the developing kidney may be related to the elevated ceramide content.

Unilateral ureteral obstruction in neonatal rats leads to renal insufficiency in adulthood

BACKGROUND

Although unilateral ureteropelvic junction obstruction is the most common cause of congenital obstructive nephropathy in infants and children, management remains controversial, and follow-up after pyeloplasty is generally limited to the pediatric ages. We have developed a model of temporary unilateral ureteral obstruction (UUO) in the neonatal rat: One month following the relief of five-day UUO, the glomerular filtration rate (GFR) of the postobstructed kidney was normal despite a 40% reduction in the number of glomeruli and residual vascular, glomerular, tubular, and interstitial injury.

METHODS

To determine whether hyperfiltration and residual injury of remaining nephrons leads to progression of renal insufficiency in later life, 31 rats were sham operated or subjected to left UUO at one day of age, with relief of UUO five days later, and were studied at one year of age. GFR was measured by inulin clearance, and the number of glomeruli, tubular atrophy, glomerular sclerosis, and interstitial fibrosis were measured by histomorphometry in sham, obstructed (UUO), and intact opposite kidneys. Intrarenal macrophages and alpha-smooth muscle actin were identified by immunohistochemistry.

RESULTS

Despite relief of UUO, ultimate growth of the postobstructed kidney was impaired. The number of glomeruli was reduced by 40%, and GFR was decreased by 80%. However, despite significant compensatory growth of the opposite kidney, there was no compensatory increase in GFR, and proteinuria was increased. Moreover, glomerular sclerosis, tubular atrophy, macrophage infiltration, and interstitial fibrosis were significantly increased not only in the postobstructed kidney, but also in the opposite kidney.

CONCLUSIONS

Although GFR is initially maintained following relief of five-day UUO in the neonatal rat, there is eventual profound loss of function of the postobstructed and opposite kidneys because of progressive tubulointerstitial and glomerular damage. These findings suggest that despite normal postoperative GFR in infancy, children undergoing pyeloplasty for ureteropelvic junction obstruction should be followed into adulthood. Elucidation of the cellular response to temporary UUO may lead to improved methods to assess renal growth, injury, and functional reserve in patients with congenital obstructive nephropathy.

Hippocampal noradrenergic neurotransmission in concurrent EEG desynchronization and inhibition of penile erection induced by cocaine in the rat

We previously reported that cocaine may induce activation of cortical (cEEG) and hippocampal (hEEG) electroencephalographic signals, concurrent with inhibition of penile erection, via an action on the hippocampal formation. The present study further evaluates the role of noradrenergic neurotransmission at the hippocampal formation in this process, using adult, male Sprague-Dawley rats anaesthetized and maintained by chloral hydrate. Unilateral microinjection of cocaine (100 nmoles) into the hippocampal CA1 or CA3 subfield or dentate gyrus elicited significant activation of both cEEG and hEEG activity. At the same time, the intracavernous pressure (ICP), our experimental index for penile erection, underwent a discernible reduction. Co-administration of equimolar doses (250 pmoles) of prazosin, naftopidil, yohimbine or rauwolscine significantly reversed those effects elicited by cocaine on cEEG, hEEG and ICP. Microinjection unilaterally of equimolar doses (5 nmoles) of norepinephrine, phenylephrine or BHT 933 into the hippocampal formation, similar to cocaine, also induced appreciable cEEG and hEEG excitation, with a simultaneous decrease in ICP. We conclude that cocaine may activate cEEG and hEEG and decrease ICP via noradrenergic neurotransmission, possibly engaging at least alpha(1A/D)-, alpha(2B)- and alpha(2C)-adrenoceptors at the hippocampal formation.

Renal tubulointerstitial injury from ureteral obstruction in the neonatal rat is attenuated by IGF-1

BACKGROUND

The administration of insulin-like growth factor-1 (IGF-1) has been shown to ameliorate the renal injury resulting from ischemic acute renal failure. As there are a number of similarities between acute renal failure and obstructive nephropathy, we examined the effects of IGF-1 on the renal cellular response to unilateral ureteral obstruction (UUO) in the neonatal rat.

METHODS

Forty-five rats were subjected to UUO or sham operation within the first 48 hours of life and received IGF-1 (2 mg/kg/day) or saline for the following three or seven days, after which kidneys were removed for study by morphometry and immunohistochemistry. To determine the effects of UUO on endogenous expression of IGF-1 and its receptor, six additional rats were subjected to UUO or sham operation, and mRNA was measured by solution hybridization.

RESULTS

There was no effect of seven days of UUO on the renal expression of endogenous IGF-1 or its receptor. Moreover, seven days of exogenous IGF-1 did not improve the suppression of nephrogenesis, the delay in glomerular maturation, or the reduction in tubular proliferation induced by ipsilateral UUO. However, in the obstructed kidney, IGF-1 reduced tubular expression of vimentin, apoptosis, and tubular atrophy by 38 to 50% (P < 0.05). In addition, IGF-1 also decreased renal interstitial collagen deposition in the obstructed kidney by 44% (P < 0.05). Following three days of UUO, the administration of IGF-1 also reduced tubular apoptosis (P < 0.05), but did not alter tubular proliferation.

CONCLUSIONS

IGF-1 has a profound salutary effect on the tubular and interstitial response to UUO in early development, without affecting glomerular injury or development. These results suggest that IGF-1 may have therapeutic potential in the management of congenital obstructive nephropathy.

Pilot study with weekly chemotherapy for patients with extensive small cell lung cancer: an Eastern Cooperative Oncology Group Study (PA586)

PURPOSE

Six of the most active chemotherapy agents in small cell lung cancer were administered sequentially in a weekly fashion in an attempt to optimize the dose and the number of agents received over a 12-week period. The purpose of this study was to estimate the efficacy and to characterize the toxicity of this approach.

PATIENTS AND METHODS

Thirty-six patients with extensive-stage small cell lung cancer received weekly treatments with cisplatin and etoposide (weeks 1, 5, and 11), cyclophosphamide (weeks 2, 7, and 10), vincristine (weeks 2, 4, 7, 8, 10, and 12), methotrexate (weeks 3, 6, and 9), and doxorubicin (weeks 4, 8, and 12). Patients achieving a partial response received a second 12-week course. Patients achieving a complete response received prophylactic cranial radiation.

RESULTS

Twenty-nine of the 36 patients completed the initial 12-week program over a median of 16 weeks. Hematologic toxicity was most prominent, with two deaths from sepsis and 31 patients having grade 3 or 4 neutropenia The overall response rate was 85%, with 33% of patients achieving a complete response. The median survival was 10.5 months, and the median time to progression was 8.2 months.

DISCUSSION

This 12-week program, consisting of administration of six active agents for small cell lung cancer, caused significant myelosuppression that resulted in significant treatment delays and dose reductions. Although a high response rate was achieved, the median overall survival of 10.5 months was not significantly longer than expected from other standard two- to three-drug regimens.

Ifosfamide, carboplatin and etoposide (ICE) in metastatic and refractory breast cancer

Twenty-five patients with metastatic breast cancer were treated with ICE after failure of previous chemotherapy. Their median age was 50 years (range 36-73). All but 1 patient had multiple sites of metastases. Nineteen (76%) patients had undergone two or more chemotherapy regimens for metastatic disease prior to ICE. The performance status (PS) of the patients was Eastern Cooperative Oncology Group (ECOG) 0:6; 1:12; 2:5; 3:2. Ifosfamide 1.25 g/m(2) over 3 h D1-3 along with mesna, etoposide 80 mg/m(2) D1-3 and carboplatin 300 mg/m(2) D1 were given every 3 weeks. We observed a partial response in 10 patients (40%, 95% confidence interval 21-62%). The response duration ranged from 1 to 15 months with a median duration of 4.5 months. The survival of all 25 patients ranged from 10 days to 25 months, with a median of 9 months. All 25 patients were evaluable for toxicity. Thirteen patients (52%) experienced grade 4 hematological toxicity, which improved after growth factor support. Four patients had leukopenic fever, 1 had gram-negative sepsis, while 2 had Clostridium difficile enterocolitis and another had herpes zoster reactivation. Four patients (16%) experienced grade 3-4 gastrointestinal (G-I) toxicity. No hepatic or renal toxicity was observed (1 patient had microscopic hematuria). One patient died of G-I bleed, and another patient died at home of undetermined cause. We conclude that ICE is an effective salvage regimen in metastatic and refractory breast cancer, even in heavily pretreated patients, and is a tolerable treatment when used with growth factor.