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Importance: The COVID-19 pandemic has severely disrupted US educational institutions. Given potential adverse financial and psychosocial effects of campus closures, many institutions developed strategies to reopen campuses in the fall 2020 semester despite the ongoing threat of COVID-19. However, many institutions opted to have limited campus reopening to minimize potential risk of spread of SARS-CoV-2., Objective: To analyze how Boston University (BU) fully reopened its campus in the fall of 2020 and controlled COVID-19 transmission despite worsening transmission in Boston, Massachusetts., Design, Setting, and Participants: This multifaceted intervention case series was conducted at a large urban university campus in Boston, Massachusetts, during the fall 2020 semester. The BU response included a high-throughput SARS-CoV-2 polymerase chain reaction testing facility with capacity to deliver results in less than 24 hours; routine asymptomatic screening for COVID-19; daily health attestations; adherence monitoring and feedback; robust contact tracing, quarantine, and isolation in on-campus facilities; face mask use; enhanced hand hygiene; social distancing recommendations; dedensification of classrooms and public places; and enhancement of all building air systems. Data were analyzed from December 20, 2020, to January 31, 2021., Main Outcomes and Measures: SARS-CoV-2 diagnosis confirmed by reverse transcription-polymerase chain reaction of anterior nares specimens and sources of transmission, as determined through contact tracing., Results: Between August and December 2020, BU conducted more than 500 000 COVID-19 tests and identified 719 individuals with COVID-19, including 496 students (69.0%), 11 faculty (1.5%), and 212 staff (29.5%). Overall, 718 individuals, or 1.8% of the BU community, had test results positive for SARS-CoV-2. Of 837 close contacts traced, 86 individuals (10.3%) had test results positive for COVID-19. BU contact tracers identified a source of transmission for 370 individuals (51.5%), with 206 individuals (55.7%) identifying a non-BU source. Among 5 faculty and 84 staff with SARS-CoV-2 with a known source of infection, most reported a transmission source outside of BU (all 5 faculty members [100%] and 67 staff members [79.8%]). A BU source was identified by 108 of 183 undergraduate students with SARS-CoV-2 (59.0%) and 39 of 98 graduate students with SARS-CoV-2 (39.8%); notably, no transmission was traced to a classroom setting., Conclusions and Relevance: In this case series of COVID-19 transmission, BU used a coordinated strategy of testing, contact tracing, isolation, and quarantine, with robust management and oversight, to control COVID-19 transmission in an urban university setting.

Background: Accurate repeat assessment of the diameter of an abdominal aortic aneurysm (AAA) is important. This study investigated the reproducibility of different methods of measuring AAA diameter from ultrasound images., Methods: Fifty AAA patients were assessed by ultrasound. Maximum AAA diameter was measured independently by three trained observers on two separate occasions using a standardised protocol. Five diameters were measured from each scan, three in the anterior-posterior (AP) and two in the transverse (TV) plane, including inner-to-inner (ITI), outer-to-outer (OTO) and leading edge-to-leading edge (LETLE). Intra- and inter-observer reproducibility were reported as reproducibility coefficients. Statistical comparison of methods was performed using linear mixed effects models., Results: Intra-observer reproducibility coefficients (AP LETLE 2.2 mm; AP ITI 2.4 mm; AP OTO 2.6 mm) were smaller than inter-observer reproducibility coefficients (AP LETLE 4.6 mm: AP ITI 4.5; and AP OTO 4.8 mm). There was no statistically significant difference in intra-observer reproducibility of three types of measurements performed in the AP plane. Measurements obtained in the TV plane had statistically significant worse intra-observer reproducibility than those performed in the AP plane., Conclusions: This study suggests that the comparison of maximum AAA diameter between repeat images is most reproducibly performed by a single trained observer measuring diameters in the AP plane.

Introduction: Dual-energy CT (DECT) can improve the accuracy of myocardial perfusion CT with projection-based monochromatic (DECT-MCE) and quantification of myocardial iodine in material decomposition (DECT-MD) reconstructions. However, evaluation of multiple reconstructions is laborious and the optimal reconstruction to detect myocardial perfusion defects is unknown., Methods: Left ventricular (LV) phantoms with artificial perfusion defects were scanned using DECT and single energy cardiac computed tomography angiography (SECT). Reconstructions of DECT-MCE at 40, 70, 100 and 140 keV, DECT-MD pairs of water, iodine, iron and fat, and SECT were evaluated using a 17-segment myocardial model. The diagnostic performance of each reconstruction was calculated on a per-segment basis and compared across DECT reconstructions., Results: Over 34 phantoms with artificial perfusion defects were found in 64/578 (11%) of segments, the sensitivity of DECT-MCE at 40, 70, 100, and 140 keV was 100% (95% confidence interval (CI): 93-100), 100% (95% CI: 93-100), 71% (95% CI: 56-83), and 25% (95% CI: 14-40), respectively, with a significant decline between 70 keV and 100 keV (p < 0.001). The specificity of DECT-MCE was 100% at all energies (95% CI: 99-100). As a group, the DECT-MD iodine background reconstructions had significantly lower sensitivity than the remaining modes (2.1% [95% CI, 0.05-11.1], vs. 100% [95% CI, 92.6-100], p < 0.001). Specificity of all material pair modes remained 100%., Conclusions: Using LV phantom models, the approach with the best sensitivity and specificity to assess myocardial perfusion defects with DECT are reconstructions of DECT-MCE at 40 or 70 KeV and DECT-MD without iodine background., Competing Interests: Conflict of interest Dr. James K. Min receives funding from GE Healthcare and serves on the scientific advisory board of Arineta and GE Healthcare. Dr. Min also has an equity interest in and is an employee of Cleerly, Inc. The remaining authors have no relevant disclosures, (Copyright © 2019. Published by Elsevier Inc.)

Objectives: Hepatitis C virus (HCV) and HIV transmission in the United States may increase as a result of increasing rates of opioid use disorder (OUD) and associated injection drug use (IDU). Epidemiologic trends among American Indian/Alaska Native (AI/AN) persons are not well known., Methods: We analyzed 2010-2014 Indian Health Service data on health care encounters to assess regional and temporal trends in IDU indicators among adults aged ≥18 years. IDU indicators included acute or chronic HCV infection (only among adults aged 18-35 years), arm cellulitis and abscess, OUD, and opioid-related overdose. We calculated rates per 10 000 AI/AN adults for each IDU indicator overall and stratified by sex, age group, and region and evaluated rate ratios and trends by using Poisson regression analysis., Results: Rates of HCV infection among adults aged 18-35 increased 9.4% per year, and rates of OUD among all adults increased 13.3% per year from 2010 to 2014. The rate of HCV infection among young women was approximately 1.3 times that among young men. Rates of opioid-related overdose among adults aged <50 years were approximately 1.4 times the rates among adults aged ≥50 years. Among young adults with HCV infection, 25.6% had concurrent OUD. Among all adults with arm cellulitis and abscess, 5.6% had concurrent OUD., Conclusions: Rates of HCV infection and OUD increased significantly in the AI/AN population. Strengthened public health efforts could ensure that AI/AN communities can address increasing needs for culturally appropriate interventions, including comprehensive syringe services programs, medication-assisted treatment, and opioid-related overdose prevention and can meet the growing need for treatment of HCV infection.

The southern United States accounted for 52% of new HIV diagnoses in 2015. Visits to primary care providers (PCPs) offer opportunities for routine HIV screening. However, of at-risk persons in the United States who visited a health care provider within the previous year, >75% were not offered a test for HIV. Perceptions of patient population risk by PCPs could offer insight into these missed opportunities, and inform development of HIV testing interventions for PCPs to increase routine screening. During April-October 2017, we conducted online surveys regarding PCP's perceptions of patient HIV risk in six areas of the South with high-HIV prevalence. Surveys queried HIV-related knowledge, beliefs, attitudes, and practices. Free-text responses to the question "Are there any unique or special risk factors relating to HIV infection in your patient population?" were analyzed using NVivo for applied thematic analysis. Of 526 respondents, the mean age was 47 years with 65% white, 13% Asian/other, 13% black, 6% Hispanic/Latino; 71% female; 93% straight/heterosexual; and 35% offered HIV screening correctly based on standard of care. Main themes revealed were as follows: (1) provider perceptions of patient risk factors (e.g., "injection drug use is rampant"), (2) provider perceptions of patient barriers to access and care (e.g., "concern for parental notification and cost for treatment"), and (3) provider misconceptions of HIV risk and patient stigmatization (e.g., "I have a low-risk population"). Our findings suggest that PCPs in the South may warrant education regarding local HIV prevalence and routine HIV screening and prevention practices.

Background: HIV diagnoses among females in the United States declined 22% from 2010 to 2015, including a 27% decline in diagnoses among black females. Despite this progress, disparities persist. Black females accounted for 60% of new HIV diagnoses among females in 2015. Geographic disparities also exist. This article describes geographic differences in HIV diagnoses among black females in the United States, from 2010 to 2015., Materials and Methods: We examined HIV surveillance data from 2010 to 2015 to determine in which geographic areas decreases or increases in HIV diagnoses occurred. We used data from the National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention's (NCHHSTP) AtlasPlus to calculate percent changes in HIV diagnosis rates by geographic region for black females ≥13 years of age., Results: The number of new HIV diagnoses declined 27% among black females from 2010 to 2015. The highest rates of HIV diagnosis per 100,000 population of black females, from 2010 to 2015, were in the Northeast and the South. In 2015, five of the eight states reporting the highest rates of HIV diagnosis (i.e., the highest quartile) were in the South., Conclusions: HIV diagnosis rates decreased nationally among black females, but the decreases were not uniform within regions or across the United States. Some states experienced increases, and black females in the South and Northeast remain disproportionately affected. Additional research is needed to ascertain factors associated with the increases to continue progress toward reducing HIV-related disparities among females in the United States.

Background: This study examines the relationship between epicardial fat volume (EFV) and lesion-specific ischemia by fractional flow reserve (FFR)., Methods: In a study of 173 patients (63.0 ± 8.3 years) undergoing FFR, EFV was determined using cardiac computed tomography. Relationships between EFV and FFR were assessed using multivariable linear and logistic regression., Results: Using multivariable linear and logistic regression, no association between EFV and FFR was observed (β [SE] = -0.001 [0.003], P = 0.6, OR [95% CI]: 1.02 [0.94-1.11], P = 0.64, respectively)., Conclusion: In patients with suspected or known coronary artery disease undergoing invasive angiography, EFV was not associated with FFR., (Published by Elsevier Inc.)

Objective: Increased brain interferon-alpha (IFNα) is associated with neurodegenerative disorders, including HIV-associated neurocognitive disorders (HAND). HAND occurs in approximately 50% of individuals with HIV despite combined antiretroviral therapy (cART). Therefore, adjunctive therapies must be developed that prevent progression of mild forms of HAND to HIV-associated dementia. Increased IFNα in the CNS has been associated with HAND in patients and in a HAND mouse model., Design and Methods: B18R binds IFNα and ameliorates HAND mouse brain histopathology (HIV encephalitis). The HAND model was used to determine if B18R with cART is superior to cART. Behavioral testing [Object recognition Test (ORT)] was used to show that B18R can reverse behavioral deficits. Rat neuronal cultures were used to investigate mechanisms of IFNα neurotoxicity., Results: Mouse brain immunohistochemistry and densitometry suggests that B18R with a common cART regimen improve histopathological markers better than cART alone. B18R reverses ORT behavioral abnormalities in HAND mice. IFNα-treated rat neurons show decreases in PSD-95, suggesting that dendritic spine architecture is disrupted. Decreases in Arf1, a GTP-binding protein, and AMPA receptors on the surface of rat neurons exposed to IFNα suggest the mechanism of IFNα neurotoxicity may relate to decreased Arf1 resulting in destabilization of dendritic spines, decreased PSD-95 expression, and internalization of AMPA receptors., Conclusion: B18R reversal of HAND in the mouse model is further evidence that the treatment of IFNα in individuals with HAND could be a viable adjunctive treatment. Investigating pathways of IFNα neurotoxicity may lead to more specific treatments.

Purpose: To compare the diagnostic value of monochromatic and material decomposition (MD) dual- energy computed tomography (DECT) imaging for the evaluation of ischemia., Methods: Patients with suspected coronary artery disease underwent rest-stress DECT and SPECT perfusion imaging. DECT images were reconstructed between 40 and 140keV and through MD of iodine/muscle., Results: MD and monochromatic imaging had a sensitivity, specificity, negative predictive, positive predictive value, and accuracy of 89%, 40%, 67%, 73% and 71%; and 91%, 67%, 67%, 91% and 86%, respectively (p=0.05)., Conclusion: DECT using monochromatic energy displayed a non-significantly higher diagnostic accuracy for myocardial ischemia as compared with DECT MD., (Published by Elsevier Inc.)

HIV diagnoses among females in the USA declined 40% during 2005-2014 with the largest decline (42%) among Black/African Americans. African American females remain disproportionately affected. We explored contributions of STD rates and sexual risk behaviors among African American females, HIV diagnoses among potential male partners, and sexual risk behaviors and viral suppression rates among HIV-positive potential male partners to declining rates of HIV diagnoses among African American females. Results suggest temporal trends in the factors that increase HIV infectiousness and transmissibility within sexual networks, i.e., decreases in rates of other sexually transmitted infections among African American females, decreases in HIV diagnoses among potential male partners, and increases in viral suppression among heterosexual and bisexual HIV-positive potential male partners in care, may explain the decline. Findings highlight a need for future research that provides context to the sexual risk behaviors and sexual network factors in order to continue progress.

Does experiencing difficulty bolster or undermine future self-images, strategies to get there and actual performance? We build on four insights from prior research to predict that accessible interpretation-of-experienced-difficulty mindset shapes identity and performance. First, people have two different interpretation-of-experienced-difficulty mindsets available in memory; their difficulty-as-impossibility mindset focuses attention on difficulty as implying low odds and their difficulty-as-importance mindset focuses attention on difficulty as implying high value. Second, people are sensitive to contextual cues as to which mindset to apply to understand their experienced difficulty. Third, people apply the mindset that comes to mind unless they have reason to question why it is "on-the-mind." Fourth, social class can be thought of as a chronic context influencing how much people endorse each interpretation-of-experienced-difficulty mindset. We used subtle primes to guide participants' attention toward either a difficulty-as-importance or a difficulty-as-impossibility mindset ( N = 591). Participants guided toward a difficulty-as-importance mindset performed better on difficult academic tasks (Studies 1, 2) than participants guided toward a difficulty-as-impossibility mindset; whether they had more school-focused possible identities and linked strategies depended on sample (Studies 3, 4). For college students, the effect of guided interpretation-of-experienced-difficulty mindset was not moderated by how much participants agreed with that mindset (Studies 1, 3, 4). College students mostly disagreed with a difficulty-as-impossibility mindset, but making that mindset accessible undermined their performance and sometimes their possible identities anyway. In contrast, middle school students (a younger and lower social class sample) were more likely to agree with a difficulty-as-impossibility mindset. In this sample (Study 2), we found an effect of mindset endorsement: agreeing that difficulty implies importance and disagreeing that difficulty implies impossibility improved performance. This study had a control group. Control group participants not guided to use a particular interpretation-of-experienced-difficulty mindset performed no differently than participants guided toward a difficulty-as-impossibility mindset. Results suggest that people may chronically act as if they are using a difficulty-as-impossibility mindset and may benefit from being guided to consider that experienced difficulty might imply task importance. Effect of accessible mindset on salience of academic possible selves was not stable, accessible mindset mattered in one university sample but not the other.

Background Following a HIV outbreak among Aboriginal people in a culturally diverse inner-city suburb of Melbourne, a blood-borne virus (BBV) screening program was conducted to inform public health interventions to prevent transmission and facilitate timely diagnosis and linkage to care., Methods: In August-September 2014, community health workers recruited people who inject drugs (PWID) from a local needle and syringe program. Participants were tested for hepatitis C virus (HCV), hepatitis B virus (HBV), HIV and syphilis and completed a bio-behavioural questionnaire., Results: In total, 128 PWID participated in the study. Serological evidence of exposure to HCV and HBV was detected among 118 (93%) and 57 participants (45%) respectively. Five participants were HIV positive. Independent risk factors for needle sharing were Aboriginality (AOR=6.21, P<0.001), attending health care for mental health problems (AOR=2.79, P=0.023) and inability to access drug treatment in the previous 6 months (AOR=4.34, P=0.023)., Conclusions: BBV prevalence in this sample was much higher than reported in other recent Australian studies. This local population is at high risk of further BBV transmission, particularly Aboriginal PWID. Individual and service-related factors associated with risk in the context of a dynamic urban drug culture and HIV outbreak suggest an urgent need for tailored harm-reduction measures.

This study examined gender differences in how internalizing and externalizing symptoms affect adolescents' decisions about smoking in Chile, where girls smoke at some of the highest rates in the world. In multivariate logistic regression analyses with 607 adolescents, internalizing symptoms, such as depressed mood and anxiety, predicted smoking among girls more than boys, with girls who were low in internalizing symptoms being more likely to smoke than those who were high in internalizing symptoms. In Chile's high-risk context, internalizing symptoms may be indirectly protective for girls by decreasing their exposure to peer pressure and related influences that encourage cigarette use.

Importance: At present, the choice of noninvasive testing for a diagnosis of significant coronary artery disease (CAD) is ambiguous, but nuclear myocardial perfusion imaging with single-photon emission tomography (SPECT) or positron emission tomography (PET) and coronary computed tomography angiography (CCTA) is predominantly used for this purpose. However, to date, prospective head-to-head studies are lacking regarding the diagnostic accuracy of these imaging modalities. Furthermore, the combination of anatomical and functional assessments configuring a hybrid approach may yield improved accuracy., Objectives: To establish the diagnostic accuracy of CCTA, SPECT, and PET and explore the incremental value of hybrid imaging compared with fractional flow reserve., Design, Setting, and Participants: A prospective clinical study involving 208 patients with suspected CAD who underwent CCTA, technetium 99m/tetrofosmin-labeled SPECT, and [15O]H2O PET with examination of all coronary arteries by fractional flow reserve was performed from January 23, 2012, to October 25, 2014. Scans were interpreted by core laboratories on an intention-to-diagnose basis. Hybrid images were generated in case of abnormal noninvasive anatomical or functional test results., Main Outcomes and Measures: Hemodynamically significant stenosis in at least 1 coronary artery as indicated by a fractional flow reserve of 0.80 or less and relative diagnostic accuracy of SPECT, PET, and CCTA in detecting hemodynamically significant CAD., Results: Of the 208 patients in the study (76 women and 132 men; mean [SD] age, 58 [9] years), 92 (44.2%) had significant CAD (fractional flow reserve ≤0.80). Sensitivity was 90% (95% CI, 82%-95%) for CCTA, 57% (95% CI, 46%-67%) for SPECT, and 87% (95% CI, 78%-93%) for PET, whereas specificity was 60% (95% CI, 51%-69%) for CCTA, 94% (95% CI, 88%-98%) for SPECT, and 84% (95% CI, 75%-89%) for PET. Single-photon emission tomography was found to be noninferior to PET in terms of specificity (P < .001) but not in terms of sensitivity (P > .99) using the predefined absolute margin of 10%. Diagnostic accuracy was highest for PET (85%; 95% CI, 80%-90%) compared with that of CCTA (74%; 95% CI, 67%-79%; P = .003) and SPECT (77%; 95% CI, 71%-83%; P = .02). Diagnostic accuracy was not enhanced by either hybrid SPECT and CCTA (76%; 95% CI, 70%-82%; P = .75) or by PET and CCTA (84%; 95% CI, 79%-89%; P = .82), but resulted in an increase in specificity (P = .004) at the cost of a decrease in sensitivity (P = .001)., Conclusions and Relevance: This controlled clinical head-to-head comparative study revealed PET to exhibit the highest accuracy for diagnosis of myocardial ischemia. Furthermore, a combined anatomical and functional assessment does not add incremental diagnostic value but guides clinical decision-making in an unsalutary fashion.

Purpose: There are limited data regarding subclinical atherosclerosis in Middle Eastern countries. We aimed to describe and compare coronary computed tomographic angiography (CCTA) findings in Qatari native and South Asian migrants at increased risk of coronary artery disease (CAD)., Methods: We performed CCTA in 251 consecutive volunteers (126 South Asian, 125 Qatari, mean age 50.0 ± 7.3 years, 27.1% female) at increased risk of cardiovascular disease. Given differences in baseline risk factors, we employed propensity score matching to create a cohort of 162 subjects for comparative analyses. We compared CAD severity, extent, plaque morphology, adverse plaque characteristics, and quantitative measures of atherosclerotic burden in both subgroups., Results: After matching, no CAD was seen in 58.0% of South Asians and 49.4% of Qataris (p = 0.3), while obstructive CAD (≥50% luminal stenosis) was present in 40.7% of South Asians and 49.4% of Qataris (p = 0.3). There was a high prevalence of adverse plaque characteristics in both ethnicities, particularly positive remodeling. South Asians had significantly smaller vessel and lumen volumes, but the percent aggregate plaque volumes were not significantly different (2.9 ± 6.3% vs. 3.8 ± 8.0%, p = 0.4)., Conclusions: In this first study of CCTA findings performed in a Middle Eastern country, we observed a high prevalence of obstructive CAD in a middle-aged cohort. There were no significant differences in CCTA findings between Qataris and South Asians after adjustment for clinical risk factors. Future studies are needed to identify patterns of coronary atherosclerosis by CCTA in non-European populations where cardiovascular disease is increasingly prevalent.

HIV infection disproportionately affects Blacks in the southern United States (U.S.), a region where legal policies that may unintentionally impede earlier HIV detection and treatment are prevalent. Historically Black Colleges and Universities (HBCUs) have historically facilitated social change in communities of color and have been underexplored as partners for HIV prevention. We describe geographic and social determinants of health (SDH) in the southern U.S. to inform potential HBCU-public health partnerships that might improve HIV health equity. We evaluated the relationship between county-level HIV prevalences (2013), HBCU geographic coordinates, and SDH variables in the southern counties with HBCUs. U.S. Census-derived SDH variables included race/ethnicity (i.e., Black, White, Hispanic), unemployment, female head of household, poverty, percent owner-occupied housing units, urbanicity, and primary care provider rates. Associations were assessed using bivariate and multivariable linear regression. Of 104 HBCUs in the contiguous U.S., 100 (96%) were located in 69 southern counties with average Black populations of 40% and an average HIV prevalence of 615. 5 per 100,000, over two times the national rate (295.1 per 100,000). In bivariable analyses, higher HIV rates in these counties were associated with higher percent Black population, unemployment, female head of household, poverty, fewer owner-occupied housing units, and greater urbanicity (p < 0.05). In multivariable analyses, counties with higher HIV rates had higher percentages of Blacks, greater urbanicity, fewer owner-occupied housing units, and more female heads of households (p < 0.05). The southern U.S. is disproportionately affected by HIV, and many HBCUs are located in affected southern counties. HBCUs may be important public health partners for helping to develop structural interventions that strengthen HIV policies in support of health equity in these southern, mostly urban counties., Competing Interests: The ICF commercial affiliation does not alter our adherence to PLOS ONE policies on sharing data and materials.

Homozygous familial hypercholesterolemia (HoFH) is a rare, inherited, life-threatening, metabolic disorder of low-density lipoprotein (LDL) receptor function characterized by elevated serum LDL cholesterol (LDL-C) and rapidly progressive atherosclerotic cardiovascular disease (ACVD). Since LDL receptors are predominantly found on hepatocytes, orthotopic liver transplantation (OLT) has emerged as a viable intervention for HoFH because LDL receptor activity is restored. This study assessed the effects of OLT on ACVD and ACVD risk factors in pediatric patients with HoFH. We analyzed lipids, lipoproteins, body mass index, glucose, blood pressure, and cardiovascular imaging in 8 pediatric patients who underwent OLT for HoFH. Total serum cholesterol, LDL-C, lipoprotein (a), and apolipoprotein B/apolipoprotein A1 ratio decreased to normal values in all subjects (p values <0.001) at 1 month after OLT and were maintained for the length of follow-up (2 to 6 years). There were few complications related to surgery or immunosuppressive therapy. Two patients developed mild hypertension. In the first 4 subjects monitored for 4 to 6 years after OLT, coronary artery disease did not develop or progress except in 1 minor artery in 1 subject and actually regressed in 2 subjects with >50% stenosis. However, aortic valve stenosis progressed in 2 of 4 subjects. In conclusion, OLT is an effective therapeutic option for patients with HoFH with coronary artery disease and persistently elevated serum LDL-C despite maximum medical therapy. Aortic valvular disease may progress. Long-term data are needed to evaluate the true risk-benefit ratio of this surgical approach., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Increased noise is a general concern for dual-energy material decomposition. Here, we develop an image-domain material decomposition algorithm for dual-energy CT (DECT) by incorporating an edge-preserving filter into the Local HighlY constrained backPRojection reconstruction (HYPR-LR) framework. With effective use of the non-local mean, the proposed algorithm, which is referred to as HYPR-NLM, reduces the noise in dual-energy decomposition while preserving the accuracy of quantitative measurement and spatial resolution of the material-specific dual-energy images. We demonstrate the noise reduction and resolution preservation of the algorithm with an iodine concentrate numerical phantom by comparing the HYPR-NLM algorithm to the direct matrix inversion, HYPR-LR and iterative image-domain material decomposition (Iter-DECT). We also show the superior performance of the HYPR-NLM over the existing methods by using two sets of cardiac perfusing imaging data. The DECT material decomposition comparison study shows that all four algorithms yield acceptable quantitative measurements of iodine concentrate. Direct matrix inversion yields the highest noise level, followed by HYPR-LR and Iter-DECT. HYPR-NLM in an iterative formulation significantly reduces image noise and the image noise is comparable to or even lower than that generated using Iter-DECT. For the HYPR-NLM method, there are marginal edge effects in the difference image, suggesting the high-frequency details are well preserved. In addition, when the search window size increases from to , there are no significant changes or marginal edge effects in the HYPR-NLM difference images. The reference drawn from the comparison study includes: (1) HYPR-NLM significantly reduces the DECT material decomposition noise while preserving quantitative measurements and high-frequency edge information, and (2) HYPR-NLM is robust with respect to parameter selection.

Cardiac computed tomography angiography (CTA) is a non-invasive method for anatomic evaluation of coronary artery stenoses. However, CTA is prone to artifacts that reduce the diagnostic accuracy to identify stenoses. Further, CTA does not allow for determination of the physiologic significance of the visualized stenoses. In this paper, we propose a new system to determine the physiologic manifestation of coronary stenoses by assessment of myocardial perfusion from typically acquired CTA images at rest. As a first step, we develop an automated segmentation method to delineate the left ventricle. Both endocardium and epicardium are compactly modeled with subdivision surfaces and coupled by explicit thickness representation. After initialization with five anatomical landmarks, the model is adapted to a target image by deformation increments including control vertex displacements and thickness variations guided by trained AdaBoost classifiers, and regularized by a prior of deformation increments from principal component analysis (PCA). The evaluation using a 5-fold cross-validation demonstrates the overall segmentation error to be 1.00 ± 0.39 mm for endocardium and 1.06 ± 0.43 mm for epicardium, with a boundary contour alignment error of 2.79 ± 0.52. Based on our LV model, two types of myocardial perfusion analyzes have been performed. One is a perfusion network analysis, which explores the correlation (as network edges) pattern of perfusion between all pairs of myocardial segments (as network nodes) defined in AHA 17-segment model. We find perfusion network display different patterns in the normal and disease groups, as divided by whether significant coronary stenosis is present in quantitative coronary angiography (QCA). The other analysis is a clinical validation assessment of the ability of the developed algorithm to predict whether a patient has significant coronary stenosis when referenced to an invasive QCA ground truth standard. By training three machine learning techniques using three features of normalized perfusion intensity, transmural perfusion ratio, and myocardial wall thickness, we demonstrate AdaBoost to be slightly better than Naive Bayes and Random Forest by the area under receiver operating characteristics (ROC) curve. For the AdaBoost algorithm, an optimal cut-point reveals an accuracy of 0.70, with sensitivity and specificity of 0.79 and 0.64, respectively. Our study shows perfusion analysis from CTA images acquired at rest is useful for providing physiologic information in diagnosis of obstructive coronary artery stenoses., (Copyright © 2015. Published by Elsevier B.V.)

Background: To determine the effect of a novel intracycle motion correction algorithm (MCA) on diagnostic accuracy of coronary computed tomographic angiography., Methods: Coronary artery phantom models were scanned at static and heart rate (HR) simulation of 60-100 beat/min and reconstructed with a conventional algorithm and MCA., Results: Among 144 coronary segments, improvements in image interpretability, quality, and diagnostic accuracy by MCA were observed for HRs of 80 and 100 (P<.05 for all), but not for HR of 60., Conclusion: Novel intracycle MCA demonstrates improved HR-dependent image interpretability, and quality and accuracy, particularly at higher HRs., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: The burden of syphilis and HIV among gay, bisexual, and other men who have sex with men (MSM) in Baltimore, Maryland, is substantial. Syphilis and HIV surveillance data were analyzed to characterize MSM with syphilis, including those with repeat infection and HIV coinfection, to strengthen prevention efforts., Methods: MSM 15 years or older from Baltimore City or County diagnosed as having early syphilis in 2010 to 2011 were included. Those previously treated for syphilis in 2007 to 2011 were considered to have repeat syphilis infection. HIV surveillance data were used to identify HIV coinfection and assess viral suppression. For MSM not diagnosed as having HIV at or before their syphilis diagnosis, annual HIV diagnosis rates were estimated, using Baltimore City data., Results: Of 460 MSM with early syphilis in 2010 or 2011, 92 (20%) had repeat infection; 55% of MSM with a single diagnosis and 86% with repeat infection were HIV coinfected. Among MSM diagnosed as having HIV, viral suppression was low (25%, or 46% of those with a viral load reported). Among Baltimore City MSM without a prior HIV diagnosis, estimated annual HIV diagnosis rates were high (5% for those with 1 syphilis diagnosis, 23% for those with repeat infection)., Conclusions: Baltimore-area MSM with syphilis, particularly those with repeat infection, represent a unique population for whom coinfection with HIV is high. Increasing frequency of syphilis and HIV testing among Baltimore area MSM with a syphilis diagnosis and prioritizing HIV-infected MSM with syphilis in efforts to achieve viral suppression may improve outcomes locally for both infections.

In 2009, the CDC National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP) initiated the online, interactive NCHHSTP Atlas. The goal of the Atlas is to strengthen the capacity to monitor the diseases overseen by NCHHSTP and to illustrate demographic, spatial, and temporal variation in disease patterns. The Atlas includes HIV, AIDS, viral hepatitis, sexually transmitted disease, and tuberculosis surveillance data, and aims to provide a single point of access to meet the analytical and data dissemination needs of NCHHSTP. To accomplish this goal, an NCHHSTP-wide Data Harmonization Workgroup reviewed surveillance data collected by each division to harmonize the data across diseases, allowing one to query data and generate comparable maps and tables via the same user interface. Although we were not able to harmonize all data elements, data standardization is necessary and work continues toward that goal.

Background: Network analysis is useful for understanding sexual transmission of HIV and other sexually transmitted infections. We conducted egocentric and affiliation network analysis among HIV-infected young black men who have sex with men (MSM) in the Jackson, Mississippi, area to understand networks and connectedness of this population., Methods: We interviewed 22 black MSM aged 17 to 25 years diagnosed as having HIV in 2006 to 2008. Participants provided demographic and geographic information about each sex partner during the 12 months before diagnosis and identified venues where they met these partners. We created affiliation network diagrams to understand connectedness of this population and identify venues that linked participants., Results: The median number of partners reported was 4 (range, 1-16); a total of 97 partners (88 of whom were male) were reported. All but 1 participant were connected through a network of venues where they had met partners during the 12 months before diagnosis. Three venues were named as places for meeting partners by 13 of 22 participants. Participants reported having partners from all regions of Mississippi and 5 other states., Conclusions: HIV-infected young black MSM in this analysis were linked by a small number of venues. These venues should be targeted for testing and prevention interventions. The pattern of meeting sex partners in a small number of venues suggests densely connected networks that propagate infection. This pattern, in combination with sexual partnerships with persons from outside Jackson, may contribute to spread of HIV and other sexually transmitted infections into or out the Jackson area.

Mitochondria have their own translational machineries for the synthesis of thirteen polypeptide chains that are components of the complexes that participate in the process of oxidative phosphorylation (or ATP generation). Translation initiation in mammalian mitochondria requires two initiation factors, IF2(mt) and IF3(mt), instead of the three that are present in eubacteria. The mammalian IF2(mt) possesses a unique 37 amino acid insertion domain, which is known to be important for the formation of the translation initiation complex. We have obtained a three-dimensional cryoelectron microscopic map of the mammalian IF2(mt) in complex with initiator fMet-tRNA(iMet) and the eubacterial ribosome. We find that the 37 amino acid insertion domain interacts with the same binding site on the ribosome that would be occupied by the eubacterial initiation factor IF1, which is absent in mitochondria. Our finding suggests that the insertion domain of IF2(mt) mimics the function of eubacterial IF1, by blocking the ribosomal aminoacyl-tRNA binding site (A site) at the initiation step.

In 2008, CDC convened an expert panel to gather input on the use of geospatial science in surveillance, research and program activities focused on CDC's Healthy Communities Goal. The panel suggested six priorities: spatially enable and strengthen public health surveillance infrastructure; develop metrics for geospatial categorization of community health and health inequity; evaluate the feasibility and validity of standard metrics of community health and health inequities; support and develop GIScience and geospatial analysis; provide geospatial capacity building, training and education; and, engage non-traditional partners. Following the meeting, the strategies and action items suggested by the expert panel were reviewed by a CDC subcommittee to determine priorities relative to ongoing CDC geospatial activities, recognizing that many activities may need to occur either in parallel, or occur multiple times across phases. Phase A of the action items centers on developing leadership support. Phase B focuses on developing internal and external capacity in both physical (e.g., software and hardware) and intellectual infrastructure. Phase C of the action items plan concerns the development and integration of geospatial methods. In summary, the panel members provided critical input to the development of CDC's strategic thinking on integrating geospatial methods and research issues across program efforts in support of its Healthy Communities Goal.

Setting: The United States (US) National Tuberculosis Surveillance System (NTSS), including 50 states, District of Columbia, and New York City., Objective: To examine disparities in characteristics and rates of Asian/Pacific Islander (API) and non-Hispanic White tuberculosis (TB) patients., Design: Descriptive analysis and logistic regression of selected 1993-2006 NTSS data. US Census Bureau Zip Code Tabulation Areas and geographic information system were used to compare API and non-Hispanic White TB patients by population density., Result: Of 253,299 TB cases, 19.8% were APIs and 23.2% were Whites; 94.2% APIs and 11.9% Whites were foreign-born. Factors that were most often associated with APIs were being female, age 15-24 years, extra-pulmonary TB, and drug resistance. APIs were less likely than Whites to be human immunodeficiency virus (HIV) positive, homeless, substance abusers, or on directly observed therapy. From 1993 to 2006, the API TB case rate declined by 42.9% vs. 66.6% in Whites (P < 0.01). Being foreign-born was the strongest risk factor for TB, regardless of population densities, but APIs were more likely to have TB than foreign-born Whites at lower population densities., Conclusion: Disparities in TB exist among US APIs and non-Hispanic Whites. TB program officials should allocate programs appropriately for foreign-born APIs in lower population density areas.

People with a serious illness such as HIV/AIDS may migrate in order to receive support from family and friends and/or better health care. In this paper, I examine the experiences of people with HIV/AIDS (PWHA) that are initial and return migrants to Wilmington, North Carolina. For the study this paper is based upon, I conducted 63 interviews of service providers, PWHA and community members in Wilmington, North Carolina. Qualitative data analysis reveals that for return migrants, migration networks made the move and getting 'into the system' easier while initial migrants struggled through the relocation process and often moved for reasons unrelated to family or friends in the area.