
UMass Memorial Health Care
Hospital / health systemWorcester, Massachusetts, United States
Research output, citation impact, and the most-cited recent papers from UMass Memorial Health Care (United States). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from UMass Memorial Health Care
Abstract The Trans-Omics for Precision Medicine (TOPMed) programme seeks to elucidate the genetic architecture and biology of heart, lung, blood and sleep disorders, with the ultimate goal of improving diagnosis, treatment and prevention of these diseases. The initial phases of the programme focused on whole-genome sequencing of individuals with rich phenotypic data and diverse backgrounds. Here we describe the TOPMed goals and design as well as the available resources and early insights obtained from the sequence data. The resources include a variant browser, a genotype imputation server, and genomic and phenotypic data that are available through dbGaP (Database of Genotypes and Phenotypes) 1 . In the first 53,831 TOPMed samples, we detected more than 400 million single-nucleotide and insertion or deletion variants after alignment with the reference genome. Additional previously undescribed variants were detected through assembly of unmapped reads and customized analysis in highly variable loci. Among the more than 400 million detected variants, 97% have frequencies of less than 1% and 46% are singletons that are present in only one individual (53% among unrelated individuals). These rare variants provide insights into mutational processes and recent human evolutionary history. The extensive catalogue of genetic variation in TOPMed studies provides unique opportunities for exploring the contributions of rare and noncoding sequence variants to phenotypic variation. Furthermore, combining TOPMed haplotypes with modern imputation methods improves the power and reach of genome-wide association studies to include variants down to a frequency of approximately 0.01%.
BACKGROUND: Patients with chronic limb-threatening ischemia (CLTI) require revascularization to improve limb perfusion and thereby limit the risk of amputation. It is uncertain whether an initial strategy of endovascular therapy or surgical revascularization for CLTI is superior for improving limb outcomes. METHODS: In this international, randomized trial, we enrolled 1830 patients with CLTI and infrainguinal peripheral artery disease in two parallel-cohort trials. Patients who had a single segment of great saphenous vein that could be used for surgery were assigned to cohort 1. Patients who needed an alternative bypass conduit were assigned to cohort 2. The primary outcome was a composite of a major adverse limb event - which was defined as amputation above the ankle or a major limb reintervention (a new bypass graft or graft revision, thrombectomy, or thrombolysis) - or death from any cause. RESULTS: In cohort 1, after a median follow-up of 2.7 years, a primary-outcome event occurred in 302 of 709 patients (42.6%) in the surgical group and in 408 of 711 patients (57.4%) in the endovascular group (hazard ratio, 0.68; 95% confidence interval [CI], 0.59 to 0.79; P<0.001). In cohort 2, a primary-outcome event occurred in 83 of 194 patients (42.8%) in the surgical group and in 95 of 199 patients (47.7%) in the endovascular group (hazard ratio, 0.79; 95% CI, 0.58 to 1.06; P = 0.12) after a median follow-up of 1.6 years. The incidence of adverse events was similar in the two groups in the two cohorts. CONCLUSIONS: Among patients with CLTI who had an adequate great saphenous vein for surgical revascularization (cohort 1), the incidence of a major adverse limb event or death was significantly lower in the surgical group than in the endovascular group. Among the patients who lacked an adequate saphenous vein conduit (cohort 2), the outcomes in the two groups were similar. (Funded by the National Heart, Lung, and Blood Institute; BEST-CLI ClinicalTrials.gov number, NCT02060630.).
The National Institute of Mental Health (NIMH) convened a meeting in September 2005 to review tobacco use and dependence and smoking cessation among those with mental disorders, especially individuals with anxiety disorders, depression, or schizophrenia. Smoking rates are exceptionally high among these individuals and contribute to the high rates of medical morbidity and mortality in these individuals. Numerous biological, psychological, and social factors may explain these high smoking rates, including the lack of smoking cessation treatment in mental health settings. Historically, "self-medication" and "individual rights" have been concerns used to rationalize allowing ongoing tobacco use and limited smoking cessation efforts in many mental health treatment settings. Although research has shown that tobacco use can reduce or ameliorate certain psychiatric symptoms, overreliance on the self-medication hypothesis to explain the high rates of tobacco use in psychiatric populations may result in inadequate attention to other potential explanations for this addictive behavior among those with mental disorders. A more complete understanding of nicotine and tobacco use in psychiatric patients also can lead to new psychiatric treatments and a better understanding of mental illness. Greater collaboration between mental health researchers and nicotine and tobacco researchers is needed to better understand and develop new treatments for cooccurring nicotine dependence and mental illness. Despite an accumulating literature for some specific psychiatric disorders and tobacco use and cessation, many unstudied research questions remain and are a focus and an emphasis of this review.
Single-center studies have reported an association between early (before day 100) cytomegalovirus (CMV) reactivation and decreased incidence of relapse for acute myeloid leukemia (AML) following allogeneic hematopoietic cell transplantation. To substantiate these preliminary findings, the Center for International Blood and Marrow Transplant Research (CIBMTR) Database was interrogated to analyze the impact of CMV reactivation on hematologic disease relapse in the current era. Data from 9469 patients transplanted with bone marrow or peripheral blood between 2003 and 2010 were analyzed according to 4 disease categories: AML (n = 5310); acute lymphoblastic leukemia (ALL, n = 1883); chronic myeloid leukemia (CML, n = 1079); and myelodysplastic syndrome (MDS, n = 1197). Median time to initial CMV reactivation was 41 days (range, 1-362 days). CMV reactivation had no preventive effect on hematologic disease relapse irrespective of diagnosis. Moreover, CMV reactivation was associated with higher nonrelapse mortality [relative risk [RR] among disease categories ranged from 1.61 to 1.95 and P values from .0002 to <.0001; 95% confidence interval [CI], 1.14-2.61). As a result, CMV reactivation was associated with lower overall survival for AML (RR = 1.27; 95% CI, 1.17-1.38; P <.0001), ALL (RR = 1.46; 95% CI, 1.25-1.71; P <.0001), CML (RR = 1.49; 95% CI, 1.19-1.88; P = .0005), and MDS (RR = 1.31; 95% CI, 1.09-1.57; P = .003). In conclusion, CMV reactivation continues to remain a risk factor for poor posttransplant outcomes and does not seem to confer protection against hematologic disease relapse.
While organizations implement information technology (IT) to effect change, current theories of IT-associated organizational change pay insufficient attention to the change goals, the role of IT in organizational change, and the multilevel nature of change processes. We take a fresh look at IT-associated organizational change using grounded theory methods. Our longitudinal study of an electronic health record (EHR) system implementation in a multi-site medical group found user behaviors that did not fit well with existing theories. Instead, we found that they fit better with the concept of affordances from ecological psychology. In developing our affordance-based theory of IT-associated organizational change from our field data, we discovered three gaps in the affordance literature; namely, the lack of theory for (1) the process of actualizing an affordance’s potential, (2) affordances in an organizational context, and (3) bundles of interrelated affordances. This paper extends the theory of affordances to handle these three gaps and, in doing so, develops a mid-range theory for EHR-associated organizational change in a healthcare organization. While the resulting theory is specific to EHR implementations, it offers a template for other mid-range affordance-actualization theories and a more general affordance-actualization lens. Our affordance-actualization lens considers the materiality of the IT artifact, the non-deterministic process by which IT leads to organizational effects, the multilevel nature of IT-associated change processes, and the intentionality of managers and users as agents of change, and thus addresses important criteria for theories of IT effects in organizations. The paper also provides practical guidance for implementing EHR systems and other organizational systems.
BACKGROUND: Those working in healthcare today are challenged more than ever before to quickly and efficiently learn from data to improve their services and delivery of care. There is broad agreement that healthcare professionals working on the front lines benefit greatly from the visual display of data presented in time order. AIM: To describe the run chart-an analytical tool commonly used by professionals in quality improvement but underutilised in healthcare. METHODS: A standard approach to the construction, use and interpretation of run charts for healthcare applications is developed based on the statistical process control literature. DISCUSSION: Run charts allow us to understand objectively if the changes we make to a process or system over time lead to improvements and do so with minimal mathematical complexity. This method of analyzing and reporting data is of greater value to improvement projects and teams than traditional aggregate summary statistics that ignore time order. Because of its utility and simplicity, the run chart has wide potential application in healthcare for practitioners and decision-makers. Run charts also provide the foundation for more sophisticated methods of analysis and learning such as Shewhart (control) charts and planned experimentation.
BACKGROUND: Microbiologic cultures, the current gold standard diagnostic method for invasive Candida infections, have low specificity and take up to 2-5 days to grow. We present the results of the first extensive multicenter clinical trial of a new nanodiagnostic approach, T2 magnetic resonance (T2MR), for diagnosis of candidemia. METHODS: Blood specimens were collected from 1801 hospitalized patients who had a blood culture ordered for routine standard of care; 250 of them were manually supplemented with concentrations from <1 to 100 colony-forming units (CFUs)/mL for 5 different Candida species. RESULTS: T2MR demonstrated an overall specificity per assay of 99.4% (95% confidence interval [CI], 99.1%-99.6%) with a mean time to negative result of 4.2 ± 0.9 hours. Subanalysis yielded a specificity of 98.9% (95% CI, 98.3%-99.4%) for Candida albicans/Candida tropicalis, 99.3% (95% CI, 98.7%-99.6%) for Candida parapsilosis, and 99.9% (95% CI, 99.7%-100.0%) for Candida krusei/Candida glabrata. The overall sensitivity was found to be 91.1% (95% CI, 86.9%-94.2%) with a mean time of 4.4 ± 1.0 hours for detection and species identification. The subgroup analysis showed a sensitivity of 92.3% (95% CI, 85.4%-96.6%) for C. albicans/C. tropicalis, 94.2% (95% CI, 84.1%-98.8%) for C. parapsilosis, and 88.1% (95% CI, 80.2%-93.7%) for C. krusei/C. glabrata. The limit of detection was 1 CFU/mL for C. tropicalis and C. krusei, 2 CFU/mL for C. albicans and C. glabrata, and 3 CFU/mL for C. parapsilosis. The negative predictive value was estimated to range from 99.5% to 99.0% in a study population with 5% and 10% prevalence of candidemia, respectively. CONCLUSIONS: T2MR is the first fully automated technology that directly analyzes whole blood specimens to identify species without the need for prior isolation of Candida species, and represents a breakthrough shift into a new era of molecular diagnostics. CLINICAL TRIALS REGISTRATION: NCT01752166.
BACKGROUND: Evidence supports the benefits of exercise for patients with cancer; however, specific guidance for clinical decision making regarding exercise timing, frequency, duration, and intensity is lacking. Efforts are needed to optimize clinical recommendations for exercise in the cancer population. OBJECTIVES: To aggregate information regarding the benefit of exercise through a systematic review of existing systematic reviews in the cancer exercise literature. DATA SOURCES: PubMed, CINAHL Plus, Scopus, Web of Science, and EMBASE. STUDY ELIGIBILITY CRITERIA: Systematic reviews and meta-analyses of the impact of movement-based exercise on the adult cancer population. METHODS: Two author teams reviewed 302 abstracts for inclusion with 93 selected for full-text review. A total of 53 studies were analyzed. A Measurement Tool to Assess Systematic Reviews (AMSTAR) was used as a quality measure of the reviews. Information was extracted using the PICO format (ie, participants, intervention, comparison, outcomes). Descriptive findings are reported. RESULTS: Mean AMSTAR score = 7.66/11 (±2.04) suggests moderate quality of the systematic reviews. Exercise is beneficial before, during, and after cancer treatment, across all cancer types, and for a variety of cancer-related impairments. Moderate-to-vigorous exercise is the best level of exercise intensity to improve physical function and mitigate cancer-related impairments. Therapeutic exercises are beneficial to manage treatment side effects, may enhance tolerance to cancer treatments, and improve functional outcomes. Supervised exercise yielded superior benefits versus unsupervised. Serious adverse events were not common. LIMITATIONS: Movement-based exercise intervention outcomes are reported. No analysis of pooled effects was calculated across reviews due to significant heterogeneity within the systematic reviews. Findings do not consider exercise in advanced cancers or pediatric populations. CONCLUSIONS: Exercise promotes significant improvements in clinical, functional, and in some populations, survival outcomes and can be recommended regardless of the type of cancer. Although generally safe, patients should be screened and appropriate precautions taken. Efforts to strengthen uniformity in clinical trial reporting, develop clinical practice guidelines, and integrate exercise and rehabilitation services into the cancer delivery system are needed.
The natural history, prognosis, and clinical significance of chronic hepatitis C are highly variable and somewhat controversial. The purpose of this study was to evaluate the effect of chronic hepatitis C infection on patients' perceptions of health-related quality of life (HRQOL) and to evaluate whether treatment with interferon improves HRQOL. A total of 642 patients with compensated liver disease who were enrolled in a multicenter trial of interferon therapy for chronic hepatitis C had evaluation of HRQOL using the SF-36 and other instruments derived from the Medical Outcomes Study (MOS). These instruments were self-administered by patients at baseline and at the end of a 24-week post-treatment observation period after 24 weeks of interferon treatment. Patients with chronic hepatitis C were compared with healthy controls (n = 750) selected from a representative sample of adults in the United States. Unadjusted and age/gender-adjusted results were similar, as were analyses using parametric or nonparametric methods. Compared with healthy controls, patients with chronic hepatitis C at baseline had lower HRQOL on all eight scales of the SF-36 (P <.001 for all). Patients without cirrhosis (n = 284 ) showed similar although slightly smaller differences. The differences were highly significant, clinically and socially relevant, and greatest for those scales that were more reflective of physical than mental or emotional disease. Patients who had a sustained viral response to interferon therapy (n = 41) exhibited marked improvements in HRQOL, and these improvements exceeded those of nonresponders on 13 of 14 HRQOL scales (8 were statistically significant). Similar improvements were noted in patients with sustained biochemical responses. The authors concluded that patients with chronic hepatitis C with or without cirrhosis have markedly reduced HRQOL. Patients who had a sustained response (virological or biochemical) to interferon therapy experienced significant improvements in perceived wellness and functional status. Successful interferon therapy provides meaningful improvements in HRQOL in patients with chronic hepatitis C.
BACKGROUND: Patients with cystic fibrosis have altered levels of plasma fatty acids. We previously demonstrated that arachidonic acid levels are increased and docosahexaenoic acid levels are decreased in affected tissues from cystic fibrosis-knockout mice. In this study we determined whether humans with mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have a similar fatty acid defect in tissues expressing CFTR. METHODS: Fatty acids from nasal- and rectal-biopsy specimens, nasal epithelial scrapings, and plasma were analyzed from 38 subjects with cystic fibrosis and compared with results in 13 obligate heterozygotes, 24 healthy controls, 11 subjects with inflammatory bowel disease, 9 subjects with upper respiratory tract infection, and 16 subjects with asthma. RESULTS: The ratio of arachidonic to docosahexaenoic acid was increased in mucosal and submucosal nasal-biopsy specimens (P<0.001) and rectal-biopsy specimens (P=0.009) from subjects with cystic fibrosis and pancreatic sufficiency and subjects with cystic fibrosis and pancreatic insufficiency, as compared with values in healthy control subjects. In nasal tissue, this change reflected an increase in arachidonic acid levels and a decrease in docosahexaenoic acid levels. In cells from nasal mucosa, the ratio of arachidonic to docosahexaenoic acid was increased in subjects with cystic fibrosis (P<0.001), as compared with healthy controls, with values in obligate heterozygotes intermediate between these two groups (P<0.001). The ratio was not increased in subjects with inflammatory bowel disease. Subjects with asthma and those with upper respiratory tract infection had values intermediate between those in subjects with cystic fibrosis and those in healthy control subjects. CONCLUSIONS: These data indicate that alterations in fatty acids similar to those in cystic fibrosis-knockout mice are present in CFTR-expressing tissue from subjects with cystic fibrosis.
Current prescribing practices for major depressive disorder (MDD) produce limited treatment success. Although pharmacogenomics may improve outcomes by identifying genetically inappropriate medications, studies to date were limited in scope. Outpatients (N = 1167) diagnosed with MDD and with a patient- or clinician-reported inadequate response to at least one antidepressant were enrolled in the Genomics Used to Improve DEpression Decisions (GUIDED) trial - a rater- and patient-blind randomized controlled trial. Patients were randomized to treatment as usual (TAU) or a pharmacogenomics-guided intervention arm in which clinicians had access to a pharmacogenomic test report to inform medication selections (guided-care). Medications were considered congruent ('use as directed' or 'use with caution' test categories) or incongruent ('use with increased caution and with more frequent monitoring' test category) with test results. Unblinding occurred after week 8. Primary outcome was symptom improvement [change in 17-item Hamilton Depression Rating Scale (HAM-D17)] at week 8; secondary outcomes were response (≥50% decrease in HAM-D17) and remission (HAM-D17 ≤ 7) at week 8. At week 8, symptom improvement for guided-care was not significantly different than TAU (27.2% versus 24.4%, p = 0.107); however, improvements in response (26.0% versus 19.9%, p = 0.013) and remission (15.3% versus 10.1%, p = 0.007) were statistically significant. Patients taking incongruent medications prior to baseline who switched to congruent medications by week 8 experienced greater symptom improvement (33.5% versus 21.1%, p = 0.002), response (28.5% versus 16.7%, p = 0.036), and remission (21.5% versus 8.5%, p = 0.007) compared to those remaining incongruent. Pharmacogenomic testing did not significantly improve mean symptoms but did significantly improve response and remission rates for difficult-to-treat depression patients over standard of care (ClinicalTrials.gov NCT02109939).
In patients with ventilator-associated pneumonia (VAP), guidelines recommend antibiotic therapy adjustment according to microbiology results after 72 h. Circulating procalcitonin levels may provide evidence that facilitates the reduction of antibiotic therapy. In a multicentre, randomised, controlled trial, 101 patients with VAP were assigned to an antibiotic discontinuation strategy according to guidelines (control group) or to serum procalcitonin concentrations (procalcitonin group) with an antibiotic regimen selected by the treating physician. The primary end-point was antibiotic-free days alive assessed 28 days after VAP onset and analysed on an intent-to-treat basis. Procalcitonin determination significantly increased the number of antibiotic free-days alive 28 days after VAP onset (13 (2-21) days versus 9.5 (1.5-17) days). This translated into a reduction in the overall duration of antibiotic therapy of 27% in the procalcitonin group (p = 0.038). After adjustment for age, microbiology and centre effect, the rate of antibiotic discontinuation on day 28 remained higher in the procalcitonin group compared with patients treated according to guidelines (hazard rate 1.6, 95% CI 1.02-2.71). The number of mechanical ventilation-free days alive, intensive care unit-free days alive, length of hospital stay and mortality rate on day 28 for the two groups were similar. Serum procalcitonin reduces antibiotic therapy exposure in patients with ventilator associated pneumonia.
The evidence for bringing behavioral health services into primary care can be confusing. Studies are quite varied in the types of programs assessed, what impacts are assessed, what kind of therapy is offered, for what populations, and on how broad a scale. By organizing the evidence into categories: whether the program is coordinated, co-located or integrated, whether for a targeted or non-targeted patient population, offering specified or unspecified behavioral health services, in a small scale or extensive implementation, programs can be compared more easily. By noting what sorts of impacts are reportedimproved access to services, clinical outcome, maintained improvement^ improved compliance, patient satisfaction, provider satisfaction, cost effectiveness or medical cost offset-the most comprehensive overall assessment of this important approach to patients' needs can be encouraged.
The widespread application of computed tomography (CT) in different clinical situations has increased the detection of intussusception, particularly non-lead point intussusception, which tends to be transient. Consequently, determining the clinical significance of intussusception seen at CT poses a diagnostic challenge. Patients with intussusception may or may not be symptomatic, and symptoms can be acute, intermittent, or chronic, making clinical diagnosis difficult. In most cases, radiologists can readily make the correct diagnosis of intestinal intussusception by noting the typical bowel-within-bowel appearance at abdominal CT. However, the CT findings that help differentiate between lead point and non-lead point intussusception have not been well studied. Nevertheless, although there is considerable overlap of CT findings, when a lead mass is seen at CT as a separate and distinct entity vis-à-vis edematous bowel, it can be considered a reliable indicator of a lead point intussusception. Differentiating between lead point and non-lead point intussusception is important in determining the appropriate treatment and has the potential to reduce the prevalence of unnecessary surgery.
BACKGROUND: Thrombotic events still occur in aspirin-treated patients with coronary artery disease. METHODS AND RESULTS: To better understand aspirin "resistance," serum thromboxane B2 (TXB2) and flow cytometric measures of arachidonic acid-induced platelet activation (before and after the ex vivo addition of aspirin and indomethacin) were analyzed in 700 consecutive aspirin-treated patients undergoing cardiac catheterization. In 680 of 682 evaluable patients, serum TXB2 concentrations were reduced compared with nonaspirinated healthy donors. Twelve patients had serum TXB2 that was lower than nonaspirinated healthy donors but >10 ng/mL. Arachidonic acid stimulated greater platelet activation in patients with high serum TXB2 (>10 ng/mL) than in patients with low serum TXB2. Addition of ex vivo aspirin reduced arachidonic acid-induced platelet activation to similar levels regardless of serum TXB2 concentrations, which suggests that patients with high residual serum TXB2 concentrations were either noncompliant or underdosed with aspirin. Among the remaining 98% of patients, ex vivo administration of either aspirin or indomethacin failed to prevent platelet activation across all degrees of arachidonic acid-induced platelet activation and aspirin doses. Although the patients were not randomized with respect to clopidogrel treatment, multivariate analysis showed that arachidonic acid-induced platelet activation was less in patients receiving clopidogrel. CONCLUSIONS: There is a residual arachidonic acid-induced platelet activation in aspirin-treated patients that (1) is caused by underdosing and/or noncompliance in only approximately 2% of patients and (2) in the remaining patients, occurs via a cyclooxygenase-1 and cyclooxygenase-2 independent pathway, in direct proportion to the degree of baseline platelet activation, and is mediated in part by adenosine diphosphate-induced platelet activation.
Few metabolites can claim a more central and versatile role in cell metabolism than acetyl coenzyme A (acetyl-CoA). Acetyl-CoA is produced during nutrient catabolism to fuel the tricarboxylic acid cycle and is the essential building block for fatty acid and isoprenoid biosynthesis. It also functions as a signalling metabolite as the substrate for lysine acetylation reactions, enabling the modulation of protein functions in response to acetyl-CoA availability. Recent years have seen exciting advances in our understanding of acetyl-CoA metabolism in normal physiology and in cancer, buoyed by new mouse models, in vivo stable-isotope tracing approaches and improved methods for measuring acetyl-CoA, including in specific subcellular compartments. Efforts to target acetyl-CoA metabolic enzymes are also advancing, with one therapeutic agent targeting acetyl-CoA synthesis receiving approval from the US Food and Drug Administration. In this Review, we give an overview of the regulation and cancer relevance of major metabolic pathways in which acetyl-CoA participates. We further discuss recent advances in understanding acetyl-CoA metabolism in normal tissues and tumours and the potential for targeting these pathways therapeutically. We conclude with a commentary on emerging nodes of acetyl-CoA metabolism that may impact cancer biology. Acetyl coenzyme A (acetyl-CoA) is a key metabolite in carbohydrate and lipid metabolism and plays a role in signalling through protein acetylation, and the dysregulation of these pathways is a hallmark of various cancers. In this Review, Guertin and Wellen give an overview of acetyl-CoA metabolism in health and in cancer and discuss emerging therapeutic strategies for targeting metabolic pathways involving acetyl-CoA.
Influenza infection increases the incidence of myocardial infarction but the reason is unknown. Platelets mediate vascular occlusion through thrombotic functions but are also recognized to have immunomodulatory activity. To determine if platelet processes are activated during influenza infection, we collected blood from 18 patients with acute influenza infection. Microscopy reveals activated platelets, many containing viral particles and extracellular-DNA associated with platelets. To understand the mechanism, we isolate human platelets and treat them with influenza A virus. Viral-engulfment leads to C3 release from platelets as a function of TLR7 and C3 leads to neutrophil-DNA release and aggregation. TLR7 specificity is confirmed in murine models lacking the receptor, and platelet depletion models support platelet-mediated C3 and neutrophil-DNA release post-influenza infection. These findings demonstrate that the initial intrinsic defense against influenza is mediated by platelet-neutrophil cross-communication that tightly regulates host immune and complement responses but can also lead to thrombotic vascular occlusion.
Direct macrophage recognition of an externalized phosphatidylserine signal on senescent erythrocytes is a process of erythrophagocytic clearance that is in line with the general clearance process of all other circulating cells that become apoptotic. Advances in deciphering this process suggest that oxidation of the erythrocyte's hemoglobin, the salient target of the free radicals encountered in the circulatory environment, may drive subsequent steps. The progressive accumulation of oxidized hemoglobin covalently bound to the membrane skeleton not only disrupts membrane organization but also threatens eventual phospholipid oxidation via a calcium-promoted quasi-lipoxygenase activity. The emergence on the cell surface of a threshold concentration of oxidized phospholipids, principally phosphatidylserine, signals recognition by the CD36 macrophage receptor.
The physical characteristics of a clinical prototype amorphous silicon-based flat panel imager for full-breast digital mammography have been investigated. The imager employs a thin thallium doped CsI scintillator on an amorphous silicon matrix of detector elements with a pixel pitch of 100 microm. Objective criteria such as modulation transfer function (MTF), noise power spectrum, detective quantum efficiency (DQE), and noise equivalent quanta were employed for this evaluation. The presampling MTF was found to be 0.73, 0.42, and 0.28 at 2, 4, and 5 cycles/mm, respectively. The measured DQE of the current prototype utilizing a 28 kVp, Mo-Mo spectrum beam hardened with 4.5 cm Lucite is approximately 55% at close to zero spatial frequency at an exposure of 32.8 mR, and decreases to approximately 40% at a low exposure of 1.3 mR. Detector element nonuniformity and electronic gain variations were not significant after appropriate calibration and software corrections. The response of the imager was linear and did not exhibit signal saturation under tested exposure conditions.
) were treated with a single intrathecal infusion of adeno-associated virus encoding a microRNA targeting SOD1. In Patient 1, SOD1 levels in spinal cord tissue as analyzed on autopsy were lower than corresponding levels in untreated patients with SOD1-mediated ALS and in healthy controls. Levels of SOD1 in cerebrospinal fluid were transiently and only slightly lower in Patient 1 but were not affected in Patient 2. In Patient 1, meningoradiculitis developed after the infusion; Patient 2 was pretreated with immunosuppressive drugs and did not have this complication. Patient 1 had transient improvement in the strength of his right leg, a measure that had been relatively stable throughout his disease course, but there was no change in his vital capacity. Patient 2 had stable scores on a composite measure of ALS function and a stable vital capacity during a 12-month period. This study showed that intrathecal microRNA can be used as a potential treatment for SOD1-mediated ALS.