The mechanisms protecting from immunopathology during acute bacterial infections are incompletely known. We found that in response to apoptotic immune cells and live or dead Listeria monocytogenes scavenger receptor BI (SR-BI), an anti-atherogenic lipid exchange mediator, activated internalization mechanisms with characteristics of macropinocytosis and, assisted by Golgi fragmentation, initiated autophagic responses. This was supported by scavenger receptor-induced local increases in membrane cholesterol concentrations which generated lipid domains particularly in cell extensions and the Golgi. SR-BI was a key driver of beclin-1-dependent autophagy during acute bacterial infection of the liver and spleen. Autophagy regulated tissue infiltration of neutrophils, suppressed accumulation of Ly6C+ (inflammatory) macrophages, and prevented hepatocyte necrosis in the core of infectious foci. Perifocal levels of Ly6C+ macrophages and Ly6C- macrophages were unaffected, indicating predominant regulation of the focus core. SR-BI-triggered autophagy promoted co-elimination of apoptotic immune cells and dead bacteria but barely influenced bacterial sequestration and survival or inflammasome activation, thus exclusively counteracting damage inflicted by immune responses. Hence, SR-BI- and autophagy promote a surveillance pathway that partially responds to products of antimicrobial defenses and selectively prevents immunity-induced damage during acute infection. Our findings suggest that control of infection-associated immunopathology can be based on a unified defense operation.
The Zn-finger domain of MdmX suppresses cancer progression by promoting genome stability in p53-mutant cells
The MDMX (MDM4) oncogene is amplified or overexpressed in a significant percentage of human tumors. MDMX is thought to function as an oncoprotein by binding p53 tumor suppressor protein to inhibit p53-mediated transcription, and by complexing with MDM2 oncoprotein to promote MDM2-mediated degradation of p53. However, down-regulation or loss of functional MDMX has also been observed in a variety of human tumors that are mutated for p53, often correlating with more aggressive cancers and a worse patient prognosis. We have previously reported that endogenous levels of MdmX can suppress proliferation and promote pseudo-bipolar mitosis in primary and tumor cells derived from p53-deficient mice, and that MdmX-p53 double deficient mice succumb to spontaneously formed tumors more rapidly than p53-deficient mice. These results suggest that the MdmX oncoprotein may act as a tumor-suppressor in cancers with compromised p53 function. By using orthotopic transplantation and lung colonization assays in mice we now establish a p53-independent anti-oncogenic role for MdmX in tumor progression. We also demonstrate that the roles of MdmX in genome stability and in proliferation are two distinct functions encoded by the separate MdmX protein domains. The central Zn-finger domain suppresses multipolar mitosis and chromosome loss, whereas the carboxy-terminal RING domain suppresses proliferation of p53-deficient cells. Furthermore, we determine that it is the maintenance of genome stability that underlies MdmX role in suppression of tumorigenesis in hyperploid p53 mutant tumors. Our results offer a rationale for the increased metastatic potential of p53 mutant human cancers with aberrant MdmX function and provide a caveat for the application of anti-MdmX treatment of tumors with compromised p53 activity.
A chimeric protein-based malaria vaccine candidate induces robust T cell responses against Plasmodium vivax MSP119
The most widespread Plasmodium species, Plasmodium vivax, poses a significant public health threat. An effective vaccine is needed to reduce global malaria burden. Of the erythrocytic stage vaccine candidates, the 19 kDa fragment of the P. vivax Merozoite Surface Protein 1 (PvMSP119) is one of the most promising. Our group has previously defined several promiscuous T helper epitopes within the PvMSP1 protein, with features that allow them to bind multiple MHC class II alleles. We describe here a P. vivax recombinant modular chimera based on MSP1 (PvRMC-MSP1) that includes defined T cell epitopes genetically fused to PvMSP119. This vaccine candidate preserved structural elements of the native PvMSP119 and elicited cytophilic antibody responses, and CD4+ and CD8+ T cells capable of recognizing PvMSP119. Although CD8+ T cells that recognize blood stage antigens have been reported to control blood infection, CD8+ T cell responses induced by P. falciparum or P. vivax vaccine candidates based on MSP119 have not been reported. To our knowledge, this is the first time a protein based subunit vaccine has been able to induce CD8+ T cell against PvMSP119. The PvRMC-MSP1 protein was also recognized by naturally acquired antibodies from individuals living in malaria endemic areas with an antibody profile associated with protection from infection. These features make PvRMC-MSP1 a promising vaccine candidate.
Results from the 2013 evaluation suggest that the Children’s Behavioral Health Initiative had a large impact on formal behavioral health screening and treatment utilization among children and adolescents enrolled in MassHealth.
The first Clinical Topic Review was conducted in order to better understand how behavioral health screenings were occurring for children and adolescents during well visits prior to the implementation of a requirement that primary care providers perform behavioral health screening using a standardized behavioral health screening tool during every well child visit.
INTRODUCTION: This study examines the outcomes of a 22-hr motivational interviewing (MI) course and compares online and in-person offerings of the course. It also evaluates clinicians' ability to accurately self-assess their MI skills.
METHOD: 34 clinicians participated in this study and completed MI workshops either in-person or online. Use of MI in an acting patient encounter was recorded early in the training and again following the training. Recordings of these encounters were coded using the Motivational Interviewing Treatment Integrity (MITI) 3.1 coding system. After each acting patient encounter clinicians also self-evaluated their use of MI.
RESULTS: Participants showed statistically significant improvement in MI skills measured by the MITI. There were no meaningful differences between the MI skills acquired by the participants in the online group compared with those who completed training in-person. There was little correlation between participants' self-assessment of MI skills and objective assessment.
DISCUSSION: It is feasible to complete MI training through synchronous online workshops. Participant self-assessment of MI skill does not appear to be a useful approach for assessing MI skill. The acquisition of MI skills by health professionals is possible via the Internet. Learning should be assessed using objective measures rather than relying on self-report.
Cellular perception and misperception: Internal models for decision-making shaped by evolutionary experience
Cells live in dynamic environments that necessitate perpetual adaptation. Since cells have limited resources to monitor external inputs, they are required to maximize the information content of perceived signals. This challenge is not unique to microscopic life: Animals use senses to perceive inputs and adequately respond. Research showed that sensory-perception is actively shaped by learning and expectation allowing internal cognitive models to "fill in the blanks" in face of limited information. We propose that cells employ analogous strategies and use internal models shaped through the long process of evolutionary adaptation. Given this perspective, we postulate that cells are prone to "misperceptions," analogous to visual illusions, leading them to incorrectly decode patterns of inputs that lie outside of their evolutionary experience. Mapping cellular misperception can serve as a fundamental approach for dissecting regulatory networks and could be harnessed to modulate cell behavior, a potentially new avenue for therapy.
Crystal structure of the DNA binding domain of the transcription factor T-bet suggests simultaneous recognition of distant genome sites
The transcription factor T-bet (Tbox protein expressed in T cells) is one of the master regulators of both the innate and adaptive immune responses. It plays a central role in T-cell lineage commitment, where it controls the TH1 response, and in gene regulation in plasma B-cells and dendritic cells. T-bet is a member of the Tbox family of transcription factors; however, T-bet coordinately regulates the expression of many more genes than other Tbox proteins. A central unresolved question is how T-bet is able to simultaneously recognize distant Tbox binding sites, which may be located thousands of base pairs away. We have determined the crystal structure of the Tbox DNA binding domain (DBD) of T-bet in complex with a palindromic DNA. The structure shows a quaternary structure in which the T-bet dimer has its DNA binding regions splayed far apart, making it impossible for a single dimer to bind both sites of the DNA palindrome. In contrast to most other Tbox proteins, a single T-bet DBD dimer binds simultaneously to identical half-sites on two independent DNA. A fluorescence-based assay confirms that T-bet dimers are able to bring two independent DNA molecules into close juxtaposition. Furthermore, chromosome conformation capture assays confirm that T-bet functions in the direct formation of chromatin loops in vitro and in vivo. The data are consistent with a looping/synapsing model for transcriptional regulation by T-bet in which a single dimer of the transcription factor can recognize and coalesce distinct genetic elements, either a promoter plus a distant regulatory element, or promoters on two different genes.
The spatial organization of genomes is studied using microscopy- and chromosome conformation capture (3C)-based methods. The two types of methods produce data that are often consistent, but there are cases where they appear discordant. These cases provide opportunities to derive better models of chromatin folding, which can reconcile the datasets.
The genome is organized into repeating topologically associated domains (TADs), each of which is spatially isolated from its neighbor by poorly understood boundary elements thought to be conserved across cell types. Here, we show that deletion of CTCF (CCCTC-binding factor)-binding sites at TAD and sub-TAD topological boundaries that form within the HoxA and HoxC clusters during differentiation not only disturbs local chromatin domain organization and regulatory interactions but also results in homeotic transformations typical of Hox gene misregulation. Moreover, our data suggest that CTCF-dependent boundary function can be modulated by competing forces, such as the self-assembly of polycomb domains within the nucleus. Therefore, CTCF boundaries are not merely static structural components of the genome but instead are locally dynamic regulatory structures that control gene expression during development.
RATIONALE: Patterns of longitudinal lung function growth and decline in childhood asthma have been shown to be important in determining risk for future respiratory ailments including chronic airway obstruction and chronic obstructive pulmonary disease.
OBJECTIVES: To determine the genetic underpinnings of lung function patterns in subjects with childhood asthma.
METHODS: We performed a genome-wide association study of 581 non-Hispanic white individuals with asthma that were previously classified by patterns of lung function growth and decline (normal growth, normal growth with early decline, reduced growth, and reduced growth with early decline). The strongest association was also measured in two additional cohorts: a small asthma cohort and a large chronic obstructive pulmonary disease metaanalysis cohort. Interaction between the genomic region encompassing the most strongly associated single-nucleotide polymorphism and nearby genes was assessed by two chromosome conformation capture assays.
MEASUREMENTS AND MAIN RESULTS: An intergenic single-nucleotide polymorphism (rs4445257) on chromosome 8 was strongly associated with the normal growth with early decline pattern compared with all other pattern groups (P = 6.7 x 10-9; odds ratio, 2.8; 95% confidence interval, 2.0-4.0); replication analysis suggested this variant had opposite effects in normal growth with early decline and reduced growth with early decline pattern groups. Chromosome conformation capture experiments indicated a chromatin interaction between rs4445257 and the promoter of the distal CSMD3 gene.
CONCLUSIONS: Early decline in lung function after normal growth is associated with a genetic polymorphism that may also protect against early decline in reduced growth groups.
Clinical trial registered with www.clinicaltrials.gov (NCT00000575).
This is a review of the book, Linked Data for Cultural Heritage, edited by Ed Jones and Michele Seikel. Published by American Library Association, 2016.
The Relevance of Ultrasound Imaging of Suspicious Axillary Lymph Nodes and Fine-needle Aspiration Biopsy in the Post-ACOSOG Z11 Era in Early Breast Cancer
RATIONALE AND OBJECTIVES: Evaluation of nodal involvement in early-stage breast cancers (T1 or T2) changed following the Z11 trial; however, not all patients meet the Z11 inclusion criteria. Hence, the relevance of ultrasound imaging of the axilla and fine-needle aspiration biopsy (FNA) in early-stage breast cancers was investigated.
MATERIALS AND METHODS: In this single-center, retrospective study, 758 subjects had pathology-verified breast cancer diagnosis over a 3-year period, of which 128 subjects with T1 or T2 breast tumors had abnormal axillary lymph nodes on ultrasound, had FNA, and proceeded to axillary surgery. Ultrasound images were reviewed and analyzed using multivariable logistic regression to identify the features predictive of positive FNA. Accuracy of FNA was quantified as the area under the receiver operating characteristic curve with axillary surgery as reference standard.
RESULTS: Of 128 subjects, 61 were positive on FNA and 65 were positive on axillary surgery. Sensitivity, specificity, positive predictive value, and negative predictive value of FNA were 52 of 65 (80%), 54 of 63 (85.7%), 52 of 61(85.2%), and 54 of 67 (80.5%), respectively. After adjusting for neoadjuvant chemotherapy between FNA and surgery, a positive FNA was associated with higher likelihood for positive axillary surgery (odds ratio: 22.7; 95% confidence interval [CI]: 7.2-71.3, P < .0001), and the accuracy of FNA was 0.801 (95% CI: 0.727-0.876). Among ultrasound imaging features, cortical thickness and abnormal hilum were predictive (P < .017) of positive FNA with accuracy of 0.817 (95% CI: 0.741-0.893).
CONCLUSIONS: Ultrasound imaging and FNA can play an important role in the management of early breast cancers even in the post-Z11 era. Higher weightage can be accorded to cortical thickness and hilum during ultrasound evaluation.
Coming Out of the Dark: A Curriculum for Teaching and Evaluating Radiology Residents' Communication Skills Through Simulation
Case report: The purpose of this pilot is to develop and implement a curriculum to teach radiology residents communication skills through simulation.
The purpose of this study was to determine (a) the frequency of apocrine metaplasia (ApoM) found on MR core biopsy of suspicious findings, and (b) to determine if there are specific MR imaging features that might obviate the need for biopsy. This HIPAA-compliant retrospective study was performed under IRB exemption for quality assurance studies. Patient demographics, MR imaging features, and pathology were reviewed. Breast lesions which underwent MR-guided biopsy, yielding ApoM on pathology analysis were included. Retrospective review of MR imaging features of these lesions was performed by two radiologists blinded to pathology results except for the presence of ApoM. Imaging features on MR assessed included location, size, morphology, T1 and T2 signals, and enhancement kinetics. Full pathology results were subsequently reviewed during data analysis. The pathology slides and imaging was subsequently reviewed by two fellowship trained radiologists and a breast pathologist to categorize the finding of ApoM into target lesion (imaging corresponds to size of lesion on pathology) versus incidental lesion. Target lesion characteristics were assessed to determine specific MRI features of ApoM. Between January 2011 to November 2012, 155 distinct breast lesions suspicious for malignancy successfully underwent MR-guided biopsy. Of the 155 lesions biopsied, 123 (79%) were benign and 32 (21%) were malignant. Of the 123 benign biopsies, ApoM was found in 57 (46%), of which 35 (61%) had no associated atypia and 22 (39%) had associated atypia. Of the 32 malignant biopsies, three (9%) had associated ApoM (DCIS in two cases and DCIS/LCIS in one case). Of the 60 cases with ApoM, only 11 (18.3%) were target lesions and 49 were incidental lesions (81.7%). Of the 60 cases with ApoM, 35 (58%) were masses (average size 0.8 cm for both with or without atypia) and 25 (42%) were nonmass enhancement (NME) (average size 2.1 cm with and 1.0 cm without atypia). Only five (14%) of 35 masses demonstrated spiculated margins, of which four were associated with atypia (80%). Of 22 lesions with atypia or other high-risk lesion, 14 (64%) were masses, most commonly with irregular margins (64%). Of the 12 T2 hyperintense lesions, only two (1.7)% had associated atypia or high-risk lesion, and none were associated with malignancy. Of the 11 target lesions, seven were T2 hyperintense. Enhancement kinetics were variable: 30 (50%) showed mixed persistent and plateau kinetics, eight (13%) persistent delayed enhancement, 10 (17%) plateau kinetics, four (7%) washout kinetics, and eight (13%) were below threshold for kinetic analysis. ApoM is a common benign pathologic result at MR-guided core biopsy for both masses and NME accounting for 39% of all biopsy results in this series. Although there is considerable variability in imaging characteristics on MR, our results suggest biopsy may be safely obviated for lesions that are subcentimeter T2 hyperintense areas of NME and short term follow-up imaging may be a reasonable alternative for these lesions.
Blog post to AEA365, a blog sponsored by the American Evaluation Association (AEA) dedicated to highlighting Hot Tips, Cool Tricks, Rad Resources, and Lessons Learned for evaluators. The American Evaluation Association is an international professional association of evaluators devoted to the application and exploration of program evaluation, personnel evaluation, technology, and many other forms of evaluation. Evaluation involves assessing the strengths and weaknesses of programs, policies, personnel, products, and organizations to improve their effectiveness.
Atrial fibrillation (AF) is an increasingly prevalent condition and the most common sustained arrhythmia encountered in ambulatory and hospital practice. Several clinical risk factors for AF include age, sex, valvular heart disease, obesity, sleep apnea, heart failure, and hypertension (HTN). Of all the risk factors, HTN is the most commonly encountered condition in patients with incident AF. Hypertension is associated with a 1.8-fold increase in the risk of developing new-onset AF and a 1.5-fold increase in the risk of progression to permanent AF. Hypertension predisposes to cardiac structural changes that influence the development of AF such as atrial remodeling. The renin angiotensin aldosterone system has been demonstrated to be a common mechanistic link in the pathogenesis of HTN and AF. Importantly, HTN is one of the few modifiable AF risk factors, and guideline-directed management of HTN may reduce the incidence of AF.
The rising U.S. prevalence of obesity has generated significant concern and demonstrates striking socioeconomic and racial/ethnic disparities. Most interventions target individual behaviors, sometimes in combination with improving the physical environment in the community but rarely involving modifications of the work environment. With 3.6 million workers earning at or below the federal minimum wage, it is imperative to understand the impact of working conditions on health and weight for lower income workers. To investigate this question, a university-community partnership created a participatory research team and conducted eight focus groups, in English and Spanish, with people holding low-wage jobs in various industries. Analysis of transcripts identified four themes: physically demanding work (illnesses, injuries, leisure-time physical activity), psychosocial work stressors (high demands, low control, low social support, poor treatment), food environment at work (available food choices, kitchen equipment), and time pressure (scheduling, having multiple jobs and responsibilities). Physical and psychosocial features of work were identified as important antecedents for overweight. In particular, nontraditional work shifts and inflexible schedules limited participants' ability to adhere to public health recommendations for diet and physical activity. Workplace programs to address obesity in low-wage workers must include the effect of working conditions as a fundamental starting point.
Decade-Long Trends (2001-2011) in the Incidence and Hospital Death Rates Associated with the In-Hospital Development of Cardiogenic Shock after Acute Myocardial Infarction
BACKGROUND: Limited information is available about relatively contemporary trends in the incidence and hospital case-fatality rates of cardiogenic shock in patients hospitalized with acute myocardial infarction. The purpose of this population-based study was to describe decade long trends (2001-2011) in the incidence and hospital case-fatality rates for patients who developed cardiogenic shock during hospitalization for an acute myocardial infarction.
METHODS AND RESULTS: The study population consisted of 5686 residents of central Massachusetts hospitalized with acute myocardial infarction at all 11 medical centers in the Worcester, MA, metropolitan area during 6 biennial periods between 2001 and 2011, who did not have cardiogenic shock at the time of hospital presentation. On average, 3.7% of these patients developed cardiogenic shock during their acute hospitalization with nonsignificant and inconsistent trends noted over time in both crude (3.7% in 2001/2003; 4.5% in 2005/2007; 2.7% in 2009/2011; P=0.19) and multivariable adjusted analyses. The overall in-hospital case-fatality rate for patients who developed cardiogenic shock was 41.4%. The crude and multivariable adjusted odds of dying after cardiogenic shock declined during the most recent study years (47.1% dying in 2001/2003, 42.0% dying in 2005/2007, and 28.6% dying in 2009/2011). Increases in the use of evidence-based cardiac medications, and interventional procedures paralleled the increasing hospital survival trends.
CONCLUSIONS: We found suggestions of a decline in the death, but not incidence, rates of cardiogenic shock over time. These encouraging trends in hospital survival are likely because of advances in the early recognition and aggressive management of patients who develop cardiogenic shock.
Reproductive Risk Factors and Coronary Heart Disease in the Women's Health Initiative Observational Study
Background: Reproductive factors provide an early window into a woman's coronary heart disease (CHD) risk; however, their contribution to CHD risk stratification is uncertain.
Methods and Results: In the Women's Health Initiative Observational Study, we constructed Cox proportional hazards models for CHD including age, pregnancy status, number of live births, age at menarche, menstrual irregularity, age at first birth, stillbirths, miscarriages, infertility > /=1 year, infertility cause, and breastfeeding. We next added each candidate reproductive factor to an established CHD risk factor model. A final model was then constructed with significant reproductive factors added to established CHD risk factors. Improvement in C statistic, net reclassification index (or net reclassification index with risk categories of < 5%, 5 to < 10%, and > /=10% 10-year risk of CHD), and integrated discriminatory index were assessed. Among 72 982 women (CHD events, n=4607; median follow-up,12.0 [interquartile range, 8.3-13.7] years; mean [standard deviation] age, 63.2 [7.2] years), an age-adjusted reproductive risk factor model had a C statistic of 0.675 for CHD. In a model adjusted for established CHD risk factors, younger age at first birth, number of still births, number of miscarriages, and lack of breastfeeding were positively associated with CHD. Reproductive factors modestly improved model discrimination (C statistic increased from 0.726 to 0.730; integrated discriminatory index, 0.0013; P < 0.0001). Net reclassification for women with events was not improved (net reclassification index events, 0.007; P=0.18); and, for women without events, net reclassification was marginally improved (net reclassification index nonevents, 0.002; P=0.04)
CONCLUSIONS: Key reproductive factors are associated with CHD independently of established CHD risk factors, very modestly improve model discrimination, and do not materially improve net reclassification.