Characterizing "collateral damage" in men and women with metastatic breast cancer (mBC) from diverse racial and ethnic backgrounds in New York City

PURPOSE

Patients from diverse racial, ethnic, and socio-economic backgrounds may be particularly vulnerable to experiencing undue social and financial burdens ("collateral damage") from a metastatic breast cancer (mBC) diagnosis; however, these challenges have not been well explored in diverse populations.

METHODS

From May 2022 to May 2023, English- or Spanish-speaking adults with mBC treated at four New York-Presbyterian (NYP) sites were invited to complete a survey that assessed collateral damage, social determinants of health, physical and psychosocial well-being, and patient-provider communication. Fisher's exact and the Kruskal-Wallis rank-sum tests assessed differences by race and ethnicity.

RESULTS

Of 87 respondents, 14% identified as Hispanic, 28% non-Hispanic Black (NHB), 41% non-Hispanic White (NHW), 7% Asian American Pacific Islander (AAPI), and 10% other/multiracial. While 100% of Hispanic, NHW, and AAPI participants reported stable housing, 29% of NHB participants were worried about losing housing (p = 0.002). Forty-two percent of Hispanic and 46% of NHB participants (vs. 8%, NHW and 0%, AAPI, p = 0.005) were food insecure; 18% of Hispanic and 17% of NHB adults indicated lack of reliable transportation in the last year (vs. 0%, NHW/AAPI, p = 0.033). Participants were generally satisfied with the quality of communication that they had with their healthcare providers and overall physical and mental well-being were modestly poorer relative to healthy population norms.

CONCLUSIONS

In our study, NHB and Hispanic mBC patients reported higher levels of financial concern and were more likely to experience food and transportation insecurity compared to NHW patients. Systematically connecting patients with resources to address unmet needs should be prioritized to identify feasible approaches to support economically vulnerable patients following an mBC diagnosis.

Effects of the COVID-19 pandemic on acute coronary syndromes in Germany during the first wave: the COVID-19 collateral damage study

BACKGROUND

Reports about the influence of the COVID-19 pandemic on the number of hospital admissions and in-hospital mortality during the first wave between March and May 2020 showed conflicting results and are limited by single-center or limited regional multicenter datasets. Aim of this analysis covering all German federal states was the comprehensive description of hospital admissions and in-hospital mortality during the first wave of the COVID-19 pandemic.

METHODS AND RESULTS

We conducted an observational study on hospital routine data (§21 KHEntgG) and included patients with the main diagnosis of acute myocardial infarction (ICD 21 and ICD 22). A total of 159 hospitals included 36,329 patients in the database, with 12,497 patients admitted with ST-elevation myocardial infarction (STEMI) and 23,832 admitted with non-ST-elevation myocardial infarction (NSTEMI). There was a significant reduction in the number of patients admitted with STEMI (3748 in 2020, 4263 in 2019 and 4486 in 2018; p < 0.01) and NSTEMI (6957 in 2020, 8437 in 2019 and 8438 in 2020; p < 0.01). These reductions were different between the Federal states of Germany. Percutaneous coronary intervention was performed more often in 2020 than in 2019 (odds ratio 1.13, 95% confidence interval [CI] 1.06-1.21) and 2018 (odds ratio 1.20, 95% CI 1.12-1.29) in NSTEMI and more often than in 2018 (odds ratio 1.26, 95% CI 1.10-1.43) in STEMI. The in-hospital mortality did not differ between the years for STEMI and NSTEMI, respectively.

CONCLUSIONS

In this large representative sample size of hospitals in Germany, we observed significantly fewer admissions for NSTEMI and STEMI during the first COVID-19 wave, while quality of in-hospital care and in-hospital mortality were not affected. Admissions for STEMI and NSTEMI during the months March to May over 3 years and corresponding in-hospital mortality for patients with STEMI and NSTEMI in 159 German hospitals. (p-value for admissions 2020 versus 2019 and 2018: < 0.01; p-value for mortality: n.s.).

Medical and cardio-vascular emergency department visits during the COVID-19 pandemic in 2020: is there a collateral damage? A retrospective routine data analysis

Background

In this retrospective routine data analysis, we investigate the number of emergency department (ED) consultations during the COVID-19 pandemic of 2020 in Germany compared to the previous year with a special focus on numbers of myocardial infarction and acute heart failure.

Methods

Aggregated case numbers for the two consecutive years 2019 and 2020 were obtained from 24 university hospitals and 9 non-university hospitals in Germany and assessed by age, gender, triage scores, disposition, care level and by ICD-10 codes including the tracer diagnoses myocardial infarction (I21) and heart failure (I50).

Results

A total of 2,216,627 ED consultations were analyzed, of which 1,178,470 occurred in 2019 and 1,038,157 in 2020. The median deviation in case numbers between 2019 and 2020 was − 14% [CI (− 11)–(− 16)]. After a marked drop in all cases in the first COVID-19 wave in spring 2020, case numbers normalized during the summer. Thereafter starting in calendar week 39 case numbers constantly declined until the end of the year 2020. The decline in case numbers predominantly concerned younger [− 16%; CI (− 13)–(− 19)], less urgent [− 18%; CI (− 12)–(− 22)] and non-admitted cases [− 17%; CI (− 13)–(− 20)] in particular during the second wave. During the entire observation period admissions for chest pain [− 13%; CI (− 21)–2], myocardial infarction [− 2%; CI (− 9)–11] and heart failure [− 2%; CI (− 10)–6] were less affected and remained comparable to the previous year.

Conclusions

ED visits were noticeably reduced during both SARS-CoV-2 pandemic waves in Germany but cardiovascular diagnoses were less affected and no refractory increase was noted. However, long-term effects cannot be ruled out and need to be analysed in future studies.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-022-02074-3.

The impact and collateral damage of COVID-19 on prostate MRI and guided biopsy operations: Society of Abdominal Radiology Prostate Cancer Disease-Focused Panel survey analysis

The Coronavirus disease 2019 (COVID-19) pandemic has significantly affected health care systems throughout the world. A Qualtrics survey was targeted for radiologists around the world to study its effect on the operations of prostate MRI studies and biopsies. Descriptive statistics were reported. A total of 60 complete responses from five continents were included in the analysis. 70% of the responses were from academic institutions. Among all participants, the median (range) number of prostate MRI was 20 (0, 135) per week before the COVID-19 pandemic versus 10 (0, 30) during the lockdown period; the median (range) number of prostate biopsies was 4.5 (0, 60) per week before the COVID-19 versus 0 (0, 12) during the lockdown period. Among the 30% who used bowel preparation for their patients prior to MRI routinely, 11% stopped the bowel preparation due to the pandemic. 47% reported that their radiology departments faced staff disruptions, while 68% reported changes in clinic schedules in other clinical departments, particularly urology, genitourinary medical oncology, and radiation oncology. Finally, COVID-19 pandemic was found to disrupt not only the clinical prostate MRI operations but also impacted prostate MRI/biopsy research in up to 50% of institutions. The impact of this collateral damage in delaying diagnosis and treatment of prostate cancer is yet to be explored.

Influence of power setting on superior vena cava potential during right pulmonary vein isolation

PURPOSE

High-power short-duration (HP-SD) ablation could reduce collateral tissue damage by shortening the conductive heating phase. However, it is difficult to evaluate the transmural effect of ablation lesions during pulmonary vein isolation (PVI) procedures. The present study aimed to evaluate the change in superior vena cava (SVC) potential delay as a surrogate marker of collateral tissue damage during right PVI, which is adjacent to SVC.

METHODS

Out of 250 consecutive patients who underwent PVI, 86 patients in whom SVC potential during sinus rhythm was recorded both before and after right PVI were analyzed. In 46 of the patients, an HP-SD setting of 45-50 W was used (HP-SD group). In the remaining 40 patients, a conventional power setting of 20-30 W was used (conventional group). We compared the change in SVC potential delay after right PVI, radiofrequency energy, and mean contact force in the anterior-superior right PVI line, which was close to the posterior aspect of SVC, between the two groups.

RESULTS

Although the total delivered radiofrequency energy (2,924 J vs. 2,604 J) and the mean contact force (18.5 g vs. 16.0 g) in the SVC overlapping area did not differ, the change in SVC potential delay after right PVI was significantly longer in the conventional group compared to the HP-SD group (5.0 ms vs. 0.0 ms, p < 0.001).

CONCLUSIONS

The changes in SVC potential delay after right PVI might be a surrogate marker of collateral tissue damage according to the used energy settings.

["Now You're Talking!"]

Die Umfrage „Jetzt Sprichst Du!“ veranschaulicht eindrücklich die psychosozialen Belastungen und die Beeinträchtigung von Kindern und Jugendlichen in Österreich während der aktuellen Coronapandemie. Im Rahmen einer Online-Umfrage wurden 5483 Kinder und Jugendliche im Alter von 6 bis 18 Jahren bezüglich ihrer Gefühle, Ängste, Sorgen und Einschätzungen im Zusammenhang mit der Coronapandemie befragt. Es zeigt sich, dass die Kinder und Jugendlichen durch die Situation geängstigt sind und Mädchen hierbei über alle Altersgruppen hinweg stärker belastet sind. In diesem Zusammenhang wird auch deutlich, dass das Risiko einer COVID-19-assoziierten Hospitalisierung ähnlich wie bei Erwachsenen von den Kindern wie Jugendlichen massiv überschätzt wird. Auch macht sich in allen Altersgruppen eine hohe Perspektivenlosigkeit aufgrund der anhaltend herausfordernden Situation bemerkbar. Ferner häufen sich Gefühle von Wut, Ärger, Einsamkeit und Traurigkeit und es zeigt sich eine alarmierende Verschlechterung der Schlafqualität und eine Zunahme der Schlafproblematiken. Die Daten der Umfrage „Jetzt Sprichst Du!“ betonen die Notwendigkeit eines unabdingbaren und raschen Handelns, um sowohl die psychosozialen, entwicklungspsychologischen als auch gesundheitlichen Kollateralschäden in dieser jungen Altersgruppe einzudämmen, soweit dies heute noch möglich ist.

New-onset atrial fibrillation: incidence, characteristics, and related events following a national COVID-19 lockdown of 5.6 million people

AIM

To determine the incidence, patient characteristics, and related events associated with new-onset atrial fibrillation (AF) during a national COVID-19 lockdown.

METHODS AND RESULTS

Using nationwide Danish registries, we included all patients, aged 18-90 years, receiving a new-onset AF diagnosis during the first 3 months of 2019 and 2020. The main comparison was between patients diagnosed during lockdown (12 March 12-1 April 2020) and patients diagnosed in the corresponding period 1 year previously. We found a lower incidence of new-onset AF during the 3 weeks of lockdown compared with the corresponding weeks in 2019 [incidence rate ratios with 95% confidence intervals (CIs) for the 3 weeks: 0.66 (0.56-0.78), 0.53 (0.45-0.64), and 0.41 (0.34-0.50)]. There was a 47% drop in total numbers (562 vs. 1053). Patients diagnosed during lockdown were younger and with a lower CHA2DS2-VASc score, while history of cancer, heart failure, and vascular disease were more prevalent. During lockdown, 30 (5.3%) patients with new-onset AF suffered an ischaemic stroke and 15 (2.7%) died, compared with 45 (4.3%) and 14 (1.3%) patients during the corresponding 2019 period, respectively. The adjusted odds ratio of a related event (ischaemic stroke or all-cause death) during lock-down compared with the corresponding weeks was 1.41 (95% CI 0.93-2.12).

CONCLUSIONS

Following a national lockdown in Denmark, a 47% drop in registered new-onset AF cases was observed. In the event of prolonged or subsequent lockdowns, the risk of undiagnosed AF patients developing complications could potentially translate into poorer outcomes in patients with AF during the COVID-19 pandemic.

Need for ensuring care for neuro-emergencies-lessons learned from the COVID-19 pandemic

Background

To investigate whether patients with critical emergency conditions are seeking or receiving the medical care that they require, we characterized the reality of care for patients presenting with neuro-emergencies during the first phase of the COVID-19 pandemic.

Methods

In this observational, longitudinal cohort study, all neurosurgical admissions that presented to our department between February 1 and April 15 during the COVID-19 pandemic and during the same time period in 2019 were identified and categorized according to the presence of a neuro-emergency, the route of admission, management, and the category of disease. Further, the clinical course of patients with aneurysmal subarachnoid hemorrhage (aSAH) and chronic subdural hematoma (cSDH) was investigated representatively for severe vascular and semi-urgent traumatic conditions that present with a wide variety of symptoms.

Results

During the pandemic, the percentage of neuro-emergencies among all neurosurgical admissions remained similar but a larger proportion presented through the emergency department than through the outpatient clinic or by referral (*p = 0.009). The total number of neuro-emergencies was significantly reduced (*p = 0.0007) across all types of disease, particularly in vascular (*p = 0.036) but also in spinal (*p = 0.007) and hydrocephalus (*p = 0.048) emergencies. Patients with spinal emergencies presented 48 h later (*p = 0.001) despite comparable symptom severity. For aSAH, the number of cases, aSAH grade, aneurysm localization, and treatment modality did not change but strikingly, elderly patients with cSDH presented less frequently, with more severe symptoms (*p = 0.046), and were less likely to reach favorable outcome (*p = 0.003) at discharge compared with previous years.

Conclusions

Despite pandemic-related restrictive measures and reallocation of resources, patients with neuro-emergencies should be encouraged to present regardless of the severity of symptoms because deferred presentation may result in adverse outcome. Thus, conservation of critical healthcare resources remains essential in spite of fighting COVID-19.

[Numbers of emergency room patients during the COVID-19 pandemic]

Hintergrund

Seit Ende März wurde deutschlandweit das Gesundheitswesen auf einen Notbetrieb umgestellt, um Ressourcen für die sich ausbreitende Coronavirus-disease-2019-Pandemie (COVID-19-Pandemie) zu schaffen. Ziel der Arbeit ist es, das Aufkommen von Notfallpatienten zur Zeit der Pandemie zu untersuchen, um Rückschlüsse auf den Einfluss der COVID-19-Pandemie auf das Patientenaufkommen in einer Notaufnahme ziehen zu können.

Material und Methoden

Im Rahmen einer deskriptiven epidemiologischen Studie wurden in dem Zeitraum vom 01.02. bis zum 30.04.2019 sowie vom 01.02. bis zum 30.04.2020 patientenbezogene Daten von insgesamt 19.357 Fällen in der zentralen Notaufnahme des Klinikums rechts der Isar erhoben und anonymisiert ausgewertet.

Ergebnisse

Trotz steigender Patientenzahlen von 2019 auf 2020 kam es von Februar auf März 2020 zu einem deutlichen Abfall der Notfälle bis auf ein Niveau unter das von 2019, der im April weiter anhielt. Dies betraf insbesondere den Fachbereich Unfallchirurgie mit einem Rückgang des mittleren Patientenaufkommens um etwa 40 %.

Im Hinblick auf die Beschwerdebilder im März 2020 zeigte sich, dass ein vermehrtes Aufkommen von Unwohlsein (+47 %) und Atemproblemen (+36 %) zu verzeichnen war, wohingegen Rückenschmerzen (−41 %), Wunden (−29 %), thorakale (−24 %) sowie abdominelle Schmerzen (−23 %) deutlich seltener vertreten waren als im Vorjahr. Bezogen auf den Schweregrad der Beschwerden wirkte sich der Rückgang vor allem auf Beschwerdebilder mit niedriger Dringlichkeitsstufe aus.

Schlussfolgerung

Im Rahmen der COVID-19-Pandemie kam es zu einem deutlichen Rückgang des Patientenaufkommens in einer der größten Notaufnahmen in München. Dies sollte bei bestehenden Krankenhauskapazitäten vermieden werden, um potenziell gesundheitlichen Schäden durch eine aufgeschobene oder ausbleibende notfallmäßige Vorstellung vorzubeugen.

Student nurses' ethical views on responses to the severe acute respiratory syndrome outbreak

BACKGROUND

Fifteen years have passed since the outbreak of severe acute respiratory syndrome in Hong Kong. At that time, there were reports of heroic acts among professionals who cared for these patients, whose bravery and professionalism were highly praised. However, there are concerns about changes in new generation of nursing professionals.

OBJECTIVE

We aimed to examine the attitude of nursing students, should they be faced with severe acute respiratory syndrome patients during their future work.

RESEARCH DESIGN

A questionnaire survey was carried out to examine the attitude among final-year nursing students to three ethical areas, namely, duty of care, resource allocation, and collateral damage.

ETHICAL CONSIDERATIONS

This study was carried out in accordance with the requirements and recommendations of the Central Research and Ethics Committee, School of Health Sciences at Caritas Institute of Higher Education.

FINDINGS

Complete responses from 102 subjects were analyzed. The overwhelming majority (96.1%) did not agree to participate in the intubation of severe acute respiratory syndrome patients if protective measures, that is, N95 mask and gown, were not available. If there were insufficient N95 masks for all the medical, nursing, and allied health workers in the hospital (resource allocation), 37.3% felt that the distribution of N95 masks should be by casting lot, while the rest disagreed. When asked about collateral damage, more than three-quarters (77.5%) said that severe acute respiratory syndrome patients should be admitted to intensive care unit. There was sex difference in nursing students' attitude toward severe acute respiratory syndrome care during pregnancy and influence of age in understanding intensive care unit care for these patients. Interestingly, 94.1% felt that there should be a separate intensive care unit for severe acute respiratory syndrome patients.

CONCLUSION

As infection control practice and isolation facilities improved over the years, relevant knowledge and nursing ethical issues related to infectious diseases should become part of nursing education and training programs, especially in preparation for outbreaks of infectious diseases or distress.

Metastatic Breast Cancer Collateral Damage Project (MBCCD): Scale development and preliminary results of the Survey of Health, Impact, Needs, and Experiences (SHINE)

PURPOSE

Until recently, people with metastatic breast cancer (MBC) had a very poor prognosis. New treatment approaches have prolonged the time that people with MBC live, but their quality of life has received less attention. Consequently, the needs and concerns across financial, vocational, psychological, social, and physical domains in MBC patients are poorly understood-particularly regarding the collateral damage or longer-term, life-altering impacts of MBC and its treatments. This study's aims were to characterize MBC-related collateral damage, identify groups most likely to experience collateral damage, and examine its associations with psychological health, illness management, and health behaviors.

METHODS

Participants (N = 515) with MBC were recruited from Dr. Susan Love Research Foundation's Army of Women® and other advocacy organizations. Participants completed questionnaires of MBC-related collateral damage, depressive symptoms, anxiety, self-efficacy for managing oncologic treatments and physical symptoms, sleep, and physical activity.

RESULTS

Eight domains of MBC-related collateral damage, as well as MBC-related benefit finding, were reliably characterized. Concerns about mortality/uncertainty were most prominent. Participants also endorsed high levels of benefit finding. Participants younger than 50 years, with limited financial resources, or with children under 18 at home reported the most collateral damage. Collateral damage was associated significantly with compromised psychological health, lower illness management efficacy, and poorer health behaviors, beyond sociodemographic and medical characteristics.

CONCLUSIONS

Subgroups of MBC patients report long-term, life-altering consequences of MBC and its treatments, which relate to important health outcomes. Clinical implications and recommendations are discussed.

Effect of outpatient antibiotics for urinary tract infections on antimicrobial resistance among commensal Enterobacteriaceae: a multinational prospective cohort study

OBJECTIVES

We quantified the impact of antibiotics prescribed in primary care for urinary tract infections (UTIs) on intestinal colonization by ciprofloxacin-resistant (CIP-RE) and extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE), while accounting for household clustering.

METHODS

Prospective cohort study from January 2011 to August 2013 at primary care sites in Belgium, Poland and Switzerland. We recruited outpatients requiring antibiotics for suspected UTIs or asymptomatic bacteriuria (exposed patients), outpatients not requiring antibiotics (non-exposed patients), and one to three household contacts for each patient. Faecal samples were tested for CIP-RE, ESBL-PE, nitrofurantoin-resistant Enterobacteriaceae (NIT-RE) and any Enterobacteriaceae at baseline (S1), end of antibiotics (S2) and 28 days after S2 (S3).

RESULTS

We included 300 households (205 exposed, 95 non-exposed) with 716 participants. Most exposed patients received nitrofurans (86; 42%) or fluoroquinolones (76; 37%). CIP-RE were identified in 16% (328/2033) of samples from 202 (28%) participants. Fluoroquinolone treatment caused transient suppression of Enterobacteriaceae (S2) and subsequent two-fold increase in CIP-RE prevalence at S3 (adjusted prevalence ratio (aPR) 2.0, 95% CI 1.2-3.4), with corresponding number-needed-to-harm of 12. Nitrofurans had no impact on CIP-RE (aPR 1.0, 95% CI 0.5-1.8) or NIT-RE. ESBL-PE were identified in 5% (107/2058) of samples from 71 (10%) participants, with colonization not associated with antibiotic exposure. Household exposure to CIP-RE or ESBL-PE was associated with increased individual risk of colonization: aPR 1.8 (95% CI 1.3-2.5) and 3.4 (95% CI 1.3-9.0), respectively.

CONCLUSIONS

These findings support avoidance of fluoroquinolones for first-line UTI therapy in primary care, and suggest potential for interventions that interrupt household circulation of resistant Enterobacteriaceae.

Fine-tuning neutrophil activation: Strategies and consequences

In spite of their important role in host defense, neutrophils can also cause severe morbidity and mortality. Neutrophils have an extensive armory necessary to eradicate pathogens, but neutrophil infiltration and activation also induces major tissue injury associated with acute and chronic inflammatory disorders. Here, we review neutrophil anti-microbial functions and discuss their individual contribution to disease pathogenesis. Furthermore, we provide an overview of the anti-inflammatory drugs that can dampen neutrophil transmigration, elastase activity, and the production of reactive oxygen species which are already in clinical trials. The discovery of potential inhibitors of the release of neutrophil extracellular trap is still in its infancy. Here, we discuss small molecule inhibitors and inhibitory receptors that show promising results in reducing neutrophil extracellular trap formation in vitro and in vivo and discuss the advantages and drawbacks of inhibiting the release of neutrophil extracellular traps as a therapeutic treatment. Specific suppression of neutrophil extracellular trap formation, preferably while other antimicrobial functions are preserved, would be an ideal approach to treat neutrophilic inflammation, since it prevents acute as well as chronic neutrophil-associated pathology.

[Alcohol's impact on children and families. A population survey]

INTRODUCTION

Alcohol is widely used among young families, and leisure time is frequently family time. Heavy alcohol consumption can adversely affect children. The objective of this work is to measure the harm to others in Chile.

SUBJECTS AND METHOD

This descriptive and probabilistic study forms part of a collaborative research funded by Thai Health and WHO. The survey was adapted by co-researchers and applied to a nationally representative sample of 1500 Chileans over 18years of age.

RESULTS

A total of 408 respondents (27.2%) lived with children at home. Of this total, 10.5% felt that the use of alcohol by any member of the family had adversely affected a child. The most common adverse effects were verbal violence (29.7%), domestic violence (23.1%), unsupervised homes (18.7%), lack of money to provide basic needs of the child (14.3%), and physical violence (7.7%). Furthermore, in 6.6% of the cases child or family services agencies became involved. In almost half of the cases (46.3%), the drinker was the father, mother or step-parents. This was followed by other relatives (24.4%) and brothers (4.9%), or guardian of the child (2.4%).

CONCLUSION

These data support the clinical observation that alcohol is common in Chilean homes. Its consumption not only damages the physical and mental health of the drinker but also those around him. Verbal violence and witnessing serious physical violence are frequent issues, as well as economic problems that end up with the inability to provide the child with its basic needs.

Host responses to interspecific brood parasitism: a by-product of adaptations to conspecific parasitism?

Background

Why have birds evolved the ability to reject eggs? Typically, foreign egg discrimination is interpreted as evidence that interspecific brood parasitism (IP) has selected for the host’s ability to recognize and eliminate foreign eggs. Fewer studies explore the alternative hypothesis that rejection of interspecific eggs is a by-product of host defenses, evolved against conspecific parasitism (CP). We performed a large scale study with replication across taxa (two congeneric Turdus thrushes), space (populations), time (breeding seasons), and treatments (three types of experimental eggs), using a consistent design of egg rejection experiments (n = 1057 nests; including controls), in areas with potential IP either present (Europe; native populations) or absent (New Zealand; introduced populations). These comparisons benefited from the known length of allopatry (one and a half centuries), with no gene flow between native and introduced populations, which is rarely available in host-parasite systems.

Results

Hosts rejected CP at unusually high rates for passerines (up to 60%). CP rejection rates were higher in populations with higher conspecific breeding densities and no risks of IP, supporting the CP hypothesis. IP rejection rates did not covary geographically with IP risk, contradicting the IP hypothesis. High egg rejection rates were maintained in the relatively long-term isolation from IP despite non-trivial rejection costs and errors.

Conclusions

These egg rejection patterns, combined with recent findings that these thrushes are currently unsuitable hosts of the obligate parasitic common cuckoo (Cuculus canorus), are in agreement with the hypothesis that the rejection of IP is a by-product of fine-tuned egg discrimination evolved due to CP. Our study highlights the importance of considering both IP and CP simultaneously as potential drivers in the evolution of egg discrimination, and illustrates how populations introduced to novel ecological contexts can provide critical insights into brood parasite-host coevolution.

Collateral damage of nonhematopoietic tissue by hematopoiesis-specific T cells results in graft-versus-host disease during an ongoing profound graft-versus-leukemia reaction

After allogeneic stem cell transplantation (allo-SCT), donor T cells may recognize minor histocompatibility antigens (MiHA) specifically expressed on cells of the recipient. It has been hypothesized that T cells recognizing hematopoiesis-restricted MiHA mediate specific graft-versus-leukemia (GVL) activity without inducing graft-versus-host disease (GVHD), whereas T cells recognizing ubiquitously expressed MiHA induce both GVL and GVHD reactivity. It also has been hypothesized that alloreactive CD4 T cells are capable of mediating specific GVL reactivity due to the hematopoiesis-restricted expression of HLA class II. However, clinical observations suggest that an overt GVL response, associated with expansion of T cells specific for hematopoiesis-restricted antigens, is often associated with GVHD reactivity. Therefore, we developed in vitro models to investigate whether alloreactive T cells recognizing hematopoiesis-restricted antigens induce collateral damage to surrounding nonhematopoietic tissues. We found that collateral damage to MiHA-negative fibroblasts was induced by misdirection of cytotoxic granules released from MiHA-specific T cells activated by MiHA-positive hematopoietic cells, resulting in granzyme-B-mediated activation of apoptosis in the surrounding fibroblasts. We demonstrated that direct contact between the activated T cell and the fibroblast is a prerequisite for this collateral damage to occur. Our data suggest that hematopoiesis-restricted T cells actively participate in an overt GVL response and may contribute to GVHD via induction of collateral damage to nonhematopoietic targets.