Identification of Selective Imidazopyridine CSF1R Inhibitors.

Colony stimulating factor-1 receptor (CSF1R or c-FMS), a class III receptor tyrosine kinase expressed on members of the mononuclear phagocyte system (MPS), plays a key role in the proper functioning of macrophages, microglia, and related cells. Aberrant signaling through CSF1R has been associated with a variety of disease states, including cancer, inflammation, and neurodegeneration. In this Letter, we detail our efforts to develop novel CSF1R inhibitors. Drawing on previously described compounds, including GW2580 (4), we have discovered a novel series of compounds based on the imidazo[4,5-b]pyridine scaffold. Initial structure-activity relationship studies culminated in the identification of 36, a lead compound with potent CSF1R biochemical and cellular activity, acceptable in vitro ADME properties, and oral exposure in rat.

Tube Thoracostomy Complications in Patients With ARDS Requiring ECMO: Worse in COVID-19 Patients?

INTRODUCTION: The incidence and management outcomes of COVID-19 patients with acute respiratory distress syndrome (ARDS) on veno-venous extracorporeal membrane oxygenation (V-V ECMO) requiring chest tubes are not well-described. This study sought to explore differences in tube thoracostomy rates and subsequent complications between patients with and without COVID-19 ARDS on V-V ECMO. MATERIALS AND METHODS: This study is a single institution, retrospective cohort study of patients with COVID-19 ARDS requiring V-V ECMO. The control cohort consisted of patients who required V-V ECMO for ARDS-related diagnoses from January 2018 to January 2021. The primary outcome was any complication following initial tube thoracostomy placement. Study approval was obtained from the Brooke Army Medical Center Institutional Review Board (C.2017.152d). RESULTS: Twenty-five COVID-19 patients and 38 controls were included. Demographic parameters did not differ between the groups. The incidence of pneumothorax was not significantly different between the two groups (44% COVID-19 vs. 22% control, OR 2.8, 95% CI 0.95-7.9, P = 0.09). Patients with COVID-19 were as likely to receive tube thoracostomy as controls (36% vs. 24%, OR 1.8, 95% CI 0.55-5.7). Complications, however, were more likely to occur in the COVID-19 group (89% vs. 33%, OR 16, 95% CI, 1.6-201, P = 0.0498). CONCLUSIONS: Tube thoracostomy placement in COVID-19 patients with ARDS requiring V-V ECMO is common, as are complications following initial placement. Clinicians should anticipate the need for re-intervention in this patient population. Small-bore (14Fr and smaller) pigtail catheters appeared to be safe and efficacious in this setting, but further study on tube thoracostomy management in ECMO patients is needed.

A Cluster Randomized Trial of Primary Care Practice Redesign to Integrate Behavioral Health for Those Who Need It Most: Patients With Multiple Chronic Conditions.

PURPOSE: Patient outcomes can improve when primary care and behavioral health providers use a collaborative system of care, but integrating these services is difficult. We tested the effectiveness of a practice intervention for improving patient outcomes by enhancing integrated behavioral health (IBH) activities. METHODS: We conducted a pragmatic, cluster randomized controlled trial. The intervention combined practice redesign, quality improvement coaching, provider and staff education, and collaborative learning. At baseline and 2 years, staff at 42 primary care practices completed the Practice Integration Profile (PIP) as a measure of IBH. Adult patients with multiple chronic medical and behavioral conditions completed the Patient-Reported Outcomes Measurement Information System (PROMIS-29) survey. Primary outcomes were the change in 8 PROMIS-29 domain scores. Secondary outcomes included change in level of integration. RESULTS: Intervention assignment had no effect on change in outcomes reported by 2,426 patients who completed both baseline and 2-year surveys. Practices assigned to the intervention improved PIP workflow scores but not PIP total scores. Baseline PIP total score was significantly associated with patient-reported function, independent of intervention. Active practices that completed intervention workbooks (n = 13) improved patient-reported outcomes and practice integration (P ≤ .05) compared with other active practices (n = 7). CONCLUSION: Intervention assignment had no effect on change in patient outcomes; however, we did observe improved patient outcomes among practices that entered the study with greater IBH. We also observed more improvement of integration and patient outcomes among active practices that completed the intervention compared to active practices that did not. Additional research is needed to understand how implementation efforts to enhance IBH can best reach patients.

Increasing Enzyme Mannose-6-Phosphate Levels but Not Miglustat Coadministration Enhances the Efficacy of Enzyme Replacement Therapy in Pompe Mice.

Pompe disease is a rare glycogen storage disorder caused by a deficiency in the lysosomal enzyme acid α-glucosidase, which leads to muscle weakness, cardiac and respiratory failure, and early mortality. Alglucosidase alfa, a recombinant human acid α-glucosidase, was the first approved treatment of Pompe disease, but its uptake into skeletal muscle via the cation-independent mannose-6-phosphate (M6P) receptor (CIMPR) is limited. Avalglucosidase alfa has received marketing authorization in several countries for infantile-onset and/or late-onset Pompe disease. This recently approved enzyme replacement therapy (ERT) was glycoengineered to maximize CIMPR binding through high-affinity interactions with ∼7 bis-M6P moieties. Recently, small molecules like the glucosylceramide synthase inhibitor miglustat were reported to increase the stability of recombinant human acid α-glucosidase, and it was suggested that an increased serum half-life would result in better glycogen clearance. Here, the effects of miglustat on alglucosidase alfa and avalglucosidase alfa stability, activity, and efficacy in Pompe mice were evaluated. Although miglustat increased the stability of both enzymes in fluorescent protein thermal shift assays and when incubated in neutral pH buffer over time, it reduced their enzymatic activity by ∼50%. Improvement in tissue glycogen clearance and transcriptional dysregulation in Pompe mice correlated with M6P levels but not with miglustat coadministration. These results further substantiate the crucial role of CIMPR binding in lysosomal targeting of ERTs. SIGNIFICANCE STATEMENT: This work describes important new insights into the treatment of Pompe disease using currently approved enzyme replacement therapies (ERTs) coadministered with miglustat. Although miglustat increased the stability of ERTs in vitro, there was no positive impact to glycogen clearance and transcriptional correction in Pompe mice. However, increasing mannose-6-phosphate levels resulted in increased cell uptake in vitro and increased glycogen clearance and transcriptional correction in Pompe mice, further underscoring the crucial role of cation-independent mannose-6-phosphate receptor-mediated lysosomal targeting for ERTs.

Integrating behavioural health and primary care: qualitative findings on contextual factors that influence integration.

BACKGROUND: Integrating behavioural health care into primary care practices may increase patients' access to behavioural health services and improve health outcomes. However, few studies have explored factors that influence integration processes. OBJECTIVE: We sought to better understand contextual factors that support or impede behavioural health integration in primary care practices. METHODS: We conducted 71 semi-structured interviews with providers, staff, and leaders from eight primary care practices in the United States with integrated behavioural health services, which were participating in a randomized control, pragmatic trial: Integrating Behavioural Health and Primary Care. Practices were selected for diversity on geographic location, size, ownership, and experience with integration. We conducted a thematic analysis of the qualitative data derived from the interviews. RESULTS: We identified four categories of contextual factors influencing behavioural health integration: leadership commitment to integration, financial considerations, workflow and communication systems, and providers' perspectives on integration and team-based healthcare. Supportive factors included leaders' commitment to integration, adequate staffing, customized communication and workflow systems, collaborative practice culture, and healthy working relationships amongst providers. Impediments included staffing issues and payment models that do not reimburse for activities required to support integrated care. CONCLUSION: Interviewees described various benefits of integration, including providers feeling better equipped to address patients' needs due to collaboration between medical and behavioural providers and resulting interdisciplinary learning. Given concerns about provider burnout, this finding warrants further study.

This study examines the integration of behavioural health services, such as mental health counselling, into primary care practices. We conducted interviews with representatives from eight primary care practices with integrated behavioural health services. The participating practices are located in diverse geographic locations across the United States, and all were engaged in a large, national project entitled Integrating Behavioural Health and Primary Care. A total of 71 healthcare providers, staff, and practice leaders were interviewed and asked to discuss the factors that influenced efforts to integrate behavioural healthcare in their primary care practice. We analysed the interview transcripts and identified factors that supported or impeded behavioural health integration. Supportive factors included practice leaders' commitment to integration, adequate staffing, customized communication and workflow systems within the practice, a collaborative practice culture, and healthy working relationships amongst the medical and behavioural health providers. Impediments included staffing issues and a lack of reimbursement from insurance companies and government payers for the time and effort that practice staff needs to devote in order to provide integrated care. Interviewees described various benefits of behavioural health integration, including providers feeling better equipped to address patients' needs due to collaboration between medical and behavioural providers.

Percutaneous Pulmonary Artery Cannulation to Treat Acute Secondary Right Heart Failure While on Veno-venous Extracorporeal Membrane Oxygenation.

Right heart failure (RHF) is a common, yet difficult to manage, complication of severe acute respiratory distress syndrome requiring extracorporeal membrane oxygenation (ECMO) that is associated with increased mortality. Reports of the use of percutaneous mechanical circulatory support devices for concurrent right heart and respiratory failure are limited. This series describes the percutaneous cannulation of the pulmonary artery for conversion from veno-venous to veno-pulmonary artery return ECMO in 21 patients who developed secondary RHF. All patients cannulated between May 2019 and September 2021 were included. Either a 19 or 21 French venous cannula was placed percutaneously into the pulmonary artery via the internal jugular or subclavian vein, providing a total of 821 days of support (median 23 [4-71] days per patient) with flows up to 6 L/min. Five patients underwent cannulation at the bedside, with the remainder performed in the cardiac catheterization laboratory. Pulmonary artery cannulation occurred after 12 [8.5-23.5] days of ECMO support. Vasoactive infusion requirements decreased significantly within 24 hours of pulmonary artery cannula placement (p = 0.0004). Nonetheless, 75% of these patients expired after a median of 12 [4-63] days of support, with three patients found to have had significant pericardial effusions peri-arrest. This cannulation technique may be an effective alternative to veno-arterial ECMO cannulation or the placement of a dual-lumen cannula for the treatment of RHF.

Argatroban for Anticoagulation in Patients Requiring Venovenous Extracorporeal Membrane Oxygenation in Coronavirus Disease 2019.

A significant proportion of patients with coronavirus disease 2019 requiring venovenous extracorporeal membrane oxygenation at our institution demonstrated heparin resistance, which in combination with a heparin shortage resulted in the transition to argatroban with or without aspirin as an alternative anticoagulation strategy. The optimal anticoagulation strategy for coronavirus disease 2019 patients requiring venovenous extracorporeal membrane oxygenation is unknown, and therefore, we sought to evaluate the efficacy and safety of argatroban with or without aspirin as an alternative anticoagulation strategy in this patient population. DESIGN: Retrospective cohort. SETTING: Single-center tertiary-care facility in Fort Sam Houston, TX, from 2020 to 2021. PATIENTS: Twenty-four patients who were cannulated for venovenous extracorporeal membrane oxygenation due to respiratory failure secondary to coronavirus disease 2019. INTERVENTIONS: Argatroban, with or without aspirin, was substituted for heparin in coronavirus disease 2019 patients requiring venovenous extracorporeal membrane oxygenation. MEASUREMENTS AND MAIN RESULTS: Eighty percent of our coronavirus disease 2019 patients requiring venovenous extracorporeal membrane oxygenation demonstrated heparin resistance, and patients who were initially started on heparin were significantly more likely to require a change to argatroban than vice versa due to difficulty achieving or maintaining therapeutic anticoagulation goals (93.4% vs 11.1%; p < 0.0001). The time to reach the therapeutic anticoagulation goal was significantly longer for patients who were initially started on heparin in comparison with argatroban (24 vs 6 hr; p = 0.0173). Bleeding and thrombotic complications were not significantly different between the two cohorts. CONCLUSIONS: Argatroban, with or without aspirin, is an effective anticoagulation strategy for patients who require venovenous extracorporeal membrane oxygenation support secondary to coronavirus disease 2019. In comparison with heparin, this anticoagulation strategy was not associated with a significant difference in bleeding or thrombotic complications, and was associated with a significantly decreased time to therapeutic anticoagulation goal, likely as a result of high rates of heparin resistance observed in this patient population.

Integrating Behavioral Health and Primary Care (IBH-PC) to improve patient-centered outcomes in adults with multiple chronic medical and behavioral health conditions: study protocol for a pragmatic cluster-randomized control trial.

BACKGROUND: Chronic diseases that drive morbidity, mortality, and health care costs are largely influenced by human behavior. Behavioral health conditions such as anxiety, depression, and substance use disorders can often be effectively managed. The majority of patients in need of behavioral health care are seen in primary care, which often has difficulty responding. Some primary care practices are providing integrated behavioral health care (IBH), where primary care and behavioral health providers work together, in one location, using a team-based approach. Research suggests there may be an association between IBH and improved patient outcomes. However, it is often difficult for practices to achieve high levels of integration. The Integrating Behavioral Health and Primary Care study responds to this need by testing the effectiveness of a comprehensive practice-level intervention designed to improve outcomes in patients with multiple chronic medical and behavioral health conditions by increasing the practice's degree of behavioral health integration. METHODS: Forty-five primary care practices, with existing onsite behavioral health care, will be recruited for this study. Forty-three practices will be randomized to the intervention or usual care arm, while 2 practices will be considered "Vanguard" (pilot) practices for developing the intervention. The intervention is a 24-month supported practice change process including an online curriculum, a practice redesign and implementation workbook, remote quality improvement coaching services, and an online learning community. Each practice's degree of behavioral health integration will be measured using the Practice Integration Profile. Approximately 75 patients with both chronic medical and behavioral health conditions from each practice will be asked to complete a series of surveys to measure patient-centered outcomes. Change in practice degree of behavioral health integration and patient-centered outcomes will be compared between the two groups. Practice-level case studies will be conducted to better understand the contextual factors influencing integration. DISCUSSION: As primary care practices are encouraged to provide IBH services, evidence-based interventions to increase practice integration will be needed. This study will demonstrate the effectiveness of one such intervention in a pragmatic, real-world setting. TRIAL REGISTRATION: ClinicalTrials.gov NCT02868983 . Registered on August 16, 2016.

An evidence-based approach to abnormal vision in the emergency department

Patients present to the ED with visual disturbances that may be painful or painless and may include loss of visual acuity, field cuts, diplopia, and headache. A detailed history and complete ocular examination are essential to obtaining the correct diagnosis and offering expedited treatment and referral. This review discusses the differential diagnosis for patients experiencing abnormal vision from a nontraumatic or minimally traumatic etiology, and reviews diagnostic and treatment strategies from an evidence-based perspective, including point-of-care ocular ultrasound. Management of the needs of special populations, such as patients with sickle cell disease, HIV, and those with a ventriculo-peritoneal shunt, is reviewed.

A Randomized Controlled Trial of an Integrated Alcohol Reduction Intervention in Patients With Hepatitis C Infection.

BACKGROUND AND AIMS: Hepatitis C virus (HCV) and alcohol use are patient risk factors for accelerated fibrosis progression, yet few randomized controlled trials have tested clinic-based alcohol interventions. APPROACH AND RESULTS: A total of 181 patients with HCV and qualifying alcohol screener scores at three liver center settings were randomly assigned to the following: (1) medical provider-delivered Screening, Brief Intervention, and Referral to Treatment (SBIRT), including motivational interviewing counseling and referral out for alcohol treatment (SBIRT-only), or (2) SBIRT plus 6 months of integrated colocated alcohol therapy (SBIRT + Alcohol Treatment). The timeline followback method was used to assess alcohol use at baseline and 3, 6, and 12 months. Coprimary outcomes were alcohol abstinence at 6 months and heavy drinking days between 6 and 12 months. Secondary outcomes included grams of alcohol consumed per week at 6 months. Mean therapy hours across 6 months were 8.8 for SBIRT-only and 10.1 for SBIRT + Alcohol Treatment participants. The proportion of participants exhibiting full alcohol abstinence increased from baseline to 3, 6, and 12 months in both treatment arms, but no significant differences were found between arms (baseline to 6 months, 7.1% to 20.5% for SBIRT-only; 4.2% to 23.3% for SBIRT + Alcohol Treatment; P = 0.70). Proportions of participants with any heavy drinking days decreased in both groups at 6 months but did not significantly differ between the SBIRT-only (87.5% to 26.7%) and SBIRT + Alcohol Treatment (85.7% to 42.1%) arms (P = 0.30). Although both arms reduced average grams of alcohol consumed per week from baseline to 6 and 12 months, between-treatment effects were not significant. CONCLUSIONS: Patients with current or prior HCV infection will engage in alcohol treatment when encouraged by liver medical providers. Liver clinics should consider implementing provider-delivered SBIRT and tailored alcohol treatment referrals as part of the standard of care.

Secreted Thrombospondin-1 Regulates Macrophage Interleukin-1ß Production and Activation through CD47.

Thrombospondin-1 regulates inflammation by engaging several cell surface receptors and by modulating activities of other secreted factors. We have uncovered a novel role of thrombospondin-1 in modulating production and activation of the proinflammatory cytokine IL-1ß by human and murine macrophages. Physiological concentrations of thrombospondin-1 limit the induction by lipopolysaccharide of IL-1ß mRNA and total protein production by human macrophages. This inhibition can be explained by the ability of thrombospondin-1 to disrupt the interaction between CD47 and CD14, thereby limiting activation of NFκB/AP-1 by lipopolysaccharide. Only the CD47-binding domain of thrombospondin-1 exhibits this activity. In contrast, CD47, CD36, and integrin-binding domains of thrombospondin-1 independently enhance the inflammasome-dependent maturation of IL-1ß in human THP-1 monocyte-derived macrophages. Correspondingly, mouse bone marrow-derived macrophages that lack either thrombospondin-1 or CD47 exhibit diminished induction of mature IL-1ß in response to lipopolysaccharide. Lack of CD47 also limits lipopolysaccharide induction of IL-1ß, NLRP3, and caspase-1 mRNAs. These data demonstrate that thrombospondin-1 exerts CD47-dependent and -independent pro-and anti-inflammatory effects on the IL-1ß pathway. Therefore, thrombospondin-1 and its receptor CD47 may be useful targets for limiting the pro-inflammatory effects of lipopolysaccharide and for treating endotoxemia.

Development and use of new therapeutics for rare diseases: views from patients, caregivers, and advocates.

BACKGROUND: Patients with rare diseases experience the health care system differently than patients with more common conditions. They can therefore provide important perspectives on the process of developing therapeutics for their conditions. METHODS: We conducted three in-person focus groups involving rare disease patients (n = 9), caregivers (n = 8), and advocates (n = 9). Focus group participants were asked to describe their experiences with a rare disease, what they would want to know about a new drug for the disease, what outcomes they believe should be assessed in drug testing, perceptions of off-label use of a drug for treating a rare disease, views on participation in clinical trials, and opinions of the US Food and Drug Administration's (FDA's) function. The coding structure was populated from the transcripts of the sessions, using Atlas.ti qualitative analysis software, and then analyzed for common themes. RESULTS: Participants described the challenges of learning to live with a poorly understood condition for which treatment is limited. Rare disease patients were willing to accept certain risks in their care in the hopes of finding some benefit, but also expressed frustrations with the costs of their care and the lack of scientific data about their treatments. They were concerned that the development and testing of therapies should, as quickly as possible, yield effective treatments to advance their quality of life. CONCLUSION: With limited therapeutic options, rare disease patients often considered off-label treatments or novel drugs that posed substantial risk. Nonetheless, rare disease patients generally appreciated the rigor of the research underlying the drugs and supported the FDA's gatekeeping role.

Innovative research methods for studying treatments for rare diseases: methodological review.

OBJECTIVE: To examine methods for generating evidence on health outcomes in patients with rare diseases. DESIGN: Methodological review of existing literature. SETTING: PubMed, Embase, and Academic Search Premier searched for articles describing innovative approaches to randomized trial design and analysis methods and methods for conducting observational research in patients with rare diseases. MAIN OUTCOME MEASURES: We assessed information related to the proposed methods, the specific rare disease being studied, and outcomes from the application of the methods. We summarize methods with respect to their advantages in studying health outcomes in rare diseases and provide examples of their application. RESULTS: We identified 46 articles that proposed or described methods for studying patient health outcomes in rare diseases. Articles covered a wide range of rare diseases and most (72%) were published in 2008 or later. We identified 16 research strategies for studying rare disease. Innovative clinical trial methods minimize sample size requirements (n=4) and maximize the proportion of patients who receive active treatment (n=2), strategies crucial to studying small populations of patients with limited treatment choices. No studies describing unique methods for conducting observational studies in patients with rare diseases were identified. CONCLUSIONS: Though numerous studies apply unique clinical trial designs and considerations to assess patient health outcomes in rare diseases, less attention has been paid to innovative methods for studying rare diseases using observational data.

Preparing emergency physicians for malpractice litigation: a joint emergency medicine residency-law school mock trial competition.

BACKGROUND: Fear of malpractice affects the daily life of many emergency physicians. Educational programs to prepare for litigation are lacking. OBJECTIVES: An educational collaboration between an emergency medicine residency and a law school, whereby a medical malpractice mock trial competition is used to teach residents basic skills for testifying in legal proceedings. METHODS: Ten residents in an academic emergency medicine program volunteered as witnesses in a malpractice mock trial competition at a law school. Residents testified two or three times and, after each appearance, were provided feedback to prepare them for subsequent rounds of testimony. They were also given access to videotaped testimony. Judges rated each resident using a nine-question survey scored on a 10-point Likert scale. Scores were compared as a group between rounds of testimony. RESULTS: Participants demonstrated significant improvement in seven of nine measured categories. p-Values reached significance in: Worked Well on Direct Examination (p < 0.001), Demeanor/Body Language (p < 0.001), Was Not Arrogant/Did Not Lose Poise on Cross-Examination (p = 0.001), Convincing Witness (p = 0.001), Appeared Knowledgeable (p = 0.012), Courtroom Attire (p = 0.012), and Expressed Themselves Clearly (p = 0.017). In addition, residents anonymously reported broad educational benefit. CONCLUSION: This novel educational collaboration taught residents about the process of litigation. It improved their communication skills and expanded their knowledge of documentation pitfalls, problems with staff interaction, and consequences of medical errors. This mutually beneficial partnership between a medical residency and a law school solidified it as a permanent feature of the residency program.

Thrombospondin-1 is a CD47-dependent endogenous inhibitor of hydrogen sulfide signaling in T cell activation.

Thrombospondin-1 is a potent suppressor of T cell activation via its receptor CD47. However, the precise mechanism for this inhibition remains unclear. Because H2S is an endogenous potentiator of T cell activation and is necessary for full T cell activation, we hypothesized that thrombospondin-1 signaling through CD47 inhibits T cell activation by antagonizing H2S signaling. Primary T cells from thrombospondin-1 null mice were more sensitive to H2S-dependent activation assessed by proliferation and induction of interleukin-2 and CD69 mRNAs. Exogenous thrombospondin-1 inhibited H2S responses in wild type and thrombospondin-1 null T cells but enhanced the same responses in CD47 null T cells. Fibronectin, which shares integrin and glycosaminoglycan binding properties with thrombospondin-1 but not CD47 binding, did not inhibit H2S signaling. A CD47-binding peptide derived from thrombospondin-1 inhibited H2S-induced activation, whereas two other functional sequences from thrombospondin-1 enhanced H2S signaling. Therefore, engaging CD47 is necessary and sufficient for thrombospondin-1 to inhibit H2S-dependent T cell activation. H2S stimulated T cell activation by potentiating MEK-dependent ERK phosphorylation, and thrombospondin-1 inhibited this signaling in a CD47-dependent manner. Thrombospondin-1 also limited activation-dependent T cell expression of the H2S biosynthetic enzymes cystathionine ß-synthase and cystathionine γ-lyase, thereby limiting the autocrine role of H2S in T cell activation. Thus, thrombospondin-1 signaling through CD47 is the first identified endogenous inhibitor of H2S signaling and constitutes a novel mechanism that negatively regulates T cell activation.

Hippocampal hyperactivation associated with cortical thinning in Alzheimer's disease signature regions in non-demented elderly adults.

Alzheimer's disease (AD) is associated with functional and structural alterations in a distributed network of brain regions supporting memory and other cognitive domains. Functional abnormalities are present in mild cognitive impairment (MCI) with evidence of early hyperactivity in medial temporal lobe regions, followed by failure of hippocampal activation as dementia develops. Atrophy in a consistent set of cortical regions, the "cortical signature of AD," has been reported at the stage of dementia, MCI, and even in clinically normal (CN) older individuals predicted to develop AD. Despite multiple lines of evidence for each of these findings, the relationship between this structural marker of AD-related neurodegeneration and this functional marker of the integrity of the episodic memory system has not yet been elucidated. We investigated this relationship in 34 nondemented older humans (CN, N = 18; MCI, N = 16). Consistent with previous studies, we found evidence of hippocampal hyperactivation in MCI compared with CN. Additionally, within this MCI group, increased hippocampal activation correlated with cortical thinning in AD-signature regions. Even within the CN group, increased hippocampal activity was negatively correlated with cortical thinning in a subset of regions, including the superior parietal lobule (r = -0.66; p < 0.01). These findings, across a continuum of nondemented and mildly impaired older adults, support the hypothesis that paradoxically increased hippocampal activity may be an early indicator of AD-related neurodegeneration in a distributed network.

Inhibiting TGF-ß activity improves respiratory function in mdx mice.

Respiratory function is the main cause of mortality in patients with Duchenne muscular dystrophy (DMD). Elevated levels of TGF-ß play a key role in the pathophysiology of DMD. To determine whether therapeutic attenuation of TGF-ß signaling improves respiratory function, mdx mice were treated from 2 weeks of age to 2 months or 9 months of age with either 1D11 (a neutralizing antibody to all three isoforms of TGF-ß), losartan (an angiotensin receptor antagonist), or a combination of the two agents. Respiratory function was measured in nonanesthetized mice by plethysmography. The 9-month-old mdx mice had elevated Penh values and decreased breathing frequency, due primarily to decreased inspiratory flow rate. All treatments normalized Penh values and increased peak inspiratory flow, leading to decreased inspiration times and breathing frequency. Additionally, forelimb grip strength was improved after 1D11 treatment at both 2 and 9 months of age, whereas, losartan improved grip strength only at 2 months. Decreased serum creatine kinase levels (significant improvement for all groups), increased diaphragm muscle fiber density, and decreased hydroxyproline levels (significant improvement for 1D11 only) also suggested improved muscle function after treatment. For all endpoints, 1D11 was equivalent or superior to losartan; coadministration of the two agents was not superior to 1D11 alone. In conclusion, TGF-ß antagonism may be a useful therapeutic approach for treating DMD patients.

Test-retest reliability of memory task functional magnetic resonance imaging in Alzheimer disease clinical trials.

OBJECTIVE: To examine the feasibility and test-retest reliability of encoding-task functional magnetic resonance imaging (fMRI) in mild Alzheimer disease (AD). DESIGN: Randomized, double-blind, placebo-controlled study. SETTING: Memory clinical trials unit. PARTICIPANTS: We studied 12 patients with mild AD (mean [SEM] Mini-Mental State Examination score, 24.0 [0.7]; mean Clinical Dementia Rating score, 1.0) who had been taking donepezil hydrochloride for more than 6 months from the placebo arm of a larger 24-week study (n = 24, 4 scans on weeks 0, 6, 12, and 24, respectively). INTERVENTIONS: Placebo and 3 face-name, paired-associate encoding, block-design blood oxygenation level-dependent fMRI scans in 12 weeks. MAIN OUTCOME MEASURES: We performed whole-brain t maps (P < .001, 5 contiguous voxels) and hippocampal regions-of-interest analyses of extent (percentage of active voxels) and magnitude (percentage of signal change) for novel-greater-than-repeated face-name contrasts. We also calculated intraclass correlation coefficients and power estimates for hippocampal regions of interest. RESULTS: Task tolerability and data yield were high (95 of 96 scans yielded favorable-quality data). Whole-brain maps were stable. Right and left hippocampal regions-of-interest intraclass correlation coefficients were 0.59 to 0.87 and 0.67 to 0.74, respectively. To detect 25.0% to 50.0% changes in week-0 to week-12 hippocampal activity using left-right extent or right magnitude with 80.0% power (2-sided α = .05) requires 14 to 51 patients. Using left magnitude requires 125 patients because of relatively small signal to variance ratios. CONCLUSIONS: Encoding-task fMRI was successfully implemented in a single-site, 24-week, AD randomized controlled trial. Week 0 to 12 whole-brain t maps were stable, and test-retest reliability of hippocampal fMRI measures ranged from moderate to substantial. Right hippocampal magnitude may be the most promising of these candidate measures in a leveraged context. These initial estimates of test-retest reliability and power justify evaluation of encoding-task fMRI as a potential biomarker for signal of effect in exploratory and proof-of-concept trials in mild AD. Validation of these results with larger sample sizes and assessment in multisite studies is warranted.

Reliability of functional magnetic resonance imaging associative encoding memory paradigms in non-demented elderly adults.

Functional magnetic resonance imaging (fMRI) holds significant potential to aid in the development of early interventions to improve memory function, and to assess longitudinal change in memory systems in aging and early Alzheimer's disease (AD). However, the test-retest reliability of hippocampal activation and of "beneficial" deactivation in the precuneus has yet to be fully established during memory encoding tasks in older subjects. Using a mixed block and event-related face-name associative encoding paradigm, we assessed the reliability of hippocampal activation and default network deactivation over a 4- to 6-week interscan interval in 27 older individuals who were cognitively normal [Clinical Dementia Rating (CDR) Scale = 0; n = 18] or mildly impaired (CDR = 0.5; n = 9). Reliability was assessed in whole brain maps and regions of interest using both a full-task paradigm of six functional runs as well as an abbreviated paradigm of the first two functional runs, which would be advantageous for use in clinical trials. We found reliable hippocampal signal response across both block- and event-related designs in the right hippocampus. Comparable reliability in hippocampal activation was found in the full and the abbreviated paradigm. Similar reliability in hippocampal activation was observed across both CDR groups overall, but the CDR 0.5 group was more variable in left hippocampal activity. Task-related deactivation in the precuneus demonstrated much greater variability than hippocampal activation in all analyses. Overall, these results are encouraging for the utility of fMRI in "Proof of Concept" clinical trials investigating the efficacy of potentially therapeutic agents for treatment of age-related memory changes, cognitive impairment, and early AD.