ABSTRACT
Sarcoidosis is a multisystem granulomatous syndrome that arises from a persistent immune response to a triggering antigen(s). There is no "gold standard" test or algorithm for the diagnosis of sarcoidosis, making the diagnosis one of exclusion. The presentation of the disease varies substantially between individuals, in both the number of organs involved, and the manifestations seen in individual organs. These qualities dictate that health care providers diagnosing sarcoidosis must consider a wide range of possible alternative diagnoses, from across a range of presentations and medical specialties (infectious, inflammatory, cardiac, neurologic). Current guideline-based diagnosis of sarcoidosis recommends fulfillment of three criteria: 1) compatible clinical presentation and/or imaging 2) demonstration of granulomatous inflammation by biopsy (when possible) and, 3) exclusion of alternative causes, but do not provide guidance on standardized strategies for exclusion of alternative diagnoses. In this review, we provide a summary of the most common differential diagnoses for sarcoidosis involvement of lung, eye, skin, central nervous system, heart, liver, and kidney. We then propose a framework for testing to exclude alternative diagnoses based on pretest probability of sarcoidosis, defined as high (typical findings with sarcoidosis involvement confirmed in another organ), moderate (typical findings in a single organ), or low (atypical/findings suggesting of an alternative diagnosis). This work highlights the need for informed and careful exclusion of alternative diagnoses in sarcoidosis.
ABSTRACT
PURPOSE OF REVIEW: The impact of healthcare disparities in the treatment, care, and outcomes of patients with sarcoidosis has been described. There is paucity of literature on ways to address these disparities with a goal to improving health outcomes for patients with sarcoidosis. RECENT FINDINGS: Recent findings in other respiratory and systemic diseases suggest that multifaceted interventions directed at improving care at various levels including individual, family, and larger societal levels have been successful in dismantling some of the social and structural barriers to care and consequently have resulted in a reduction in disparate disease outcomes. We explore what some of these interventions would look like in sarcoidosis. SUMMARY: The impact of healthcare disparities in the treatment, care, and outcomes of patients with sarcoidosis has been described. We outline various steps and approaches aimed at addressing these health disparities with a goal to improving outcomes for those most impacted by disease.
Subject(s)
Healthcare Disparities , Sarcoidosis , Humans , Sarcoidosis/therapy , Sarcoidosis/diagnosis , Sarcoidosis/epidemiology , Health Services AccessibilityABSTRACT
BACKGROUND: Due to the heterogeneity of sarcoidosis, there is a need to define clinical phenotypes to allow for tailoring of clinical care and identification of more homogenous populations to facilitate research. METHODS: We utilized data from a prospectively collected registry of sarcoidosis patients seen at a single quaternary referral center between January 2019 and February 2021. We used multiple correspondence analysis (MCA) and k-means clustering to investigate if the clusters previously identified in the GenPhenReSa study were reproducible in a US population. We also investigated if these clusters were stable when the population was stratified by race. RESULTS: We replicated 3 of the 5 clusters seen in the GenPhenReSa study in our cohort. We likewise identified similar clusters between White and Black patients with sarcoidosis. Differences in organ manifestations associations between White and Black patients were seen primarily in relation to cardiac, neurologic, and ocular involvement. CONCLUSIONS: The organ clusters of liver-spleen, isolated pulmonary, and musculoskeletal-skin were reproducible in a US cohort, and in both Black and White patients.
Subject(s)
Black or African American , Registries , Sarcoidosis , White People , Adult , Aged , Female , Humans , Male , Middle Aged , Black or African American/statistics & numerical data , Cluster Analysis , Liver/pathology , Liver/diagnostic imaging , Prospective Studies , Sarcoidosis/ethnology , Sarcoidosis/pathology , Sarcoidosis/epidemiology , Skin Diseases/ethnology , Skin Diseases/pathology , Spleen/pathology , United States/epidemiology , White People/statistics & numerical data , WhiteABSTRACT
Cardiac tumors of the left ventricle are rare, and cardiac magnetic resonance is the preferred imaging tool for evaluation given superior tissue characterization. We present a case of a patient with arrhythmia and left ventricular mass that was ultimately diagnosed with cardiac sarcoidosis, reminding us that tissue is the issue.
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BACKGROUND: Community advisory boards (CABs) are increasingly recognized as a means of incorporating patient experience into clinical practice and research. The power of CABs is derived from engaging with community members as equals throughout the research process. Despite this, little is known of community member experience and views on best practices for running a CAB in a rare pulmonary disease. RESEARCH QUESTION: What are CAB members' views on the best practices for CAB formation and maintenance in a rare pulmonary disease? STUDY DESIGN AND METHODS: In August 2021, we formed the Cleveland Clinic Sarcoidosis Health Partners (CC-HP) as a CAB to direct research and clinic improvement initiatives at a quaternary sarcoidosis center. We collaboratively evaluated our process for formation and maintenance of the CC-HP with the patient members of the group. Through the series of reflection/debriefing discussions, CAB patient members developed a consensus account of salient obstacles and facilitators of forming and maintaining a CAB in a rare pulmonary disease. RESULTS: Clinician and community members of the CC-HP found published guidelines to be an effective tool for structuring formation of a CAB in a rare pulmonary disease. Facilitators included a dedicated coordinator, collaborative development of projects, and a focus on improving clinical care. Obstacles to CAB functioning were formal structure, focus on projects with academic merit but no immediate impact to patients, and overreliance on digital resources. INTERPRETATION: By centering our evaluation of our CAB on community member experience, we were able to both identify facilitators and impediments to CAB as well as improve our own processes.
Subject(s)
Advisory Committees , Humans , Sarcoidosis/therapyABSTRACT
Cardiac involvement is a major cause of morbidity and mortality in patients with sarcoidosis. It is important to distinguish between clinical manifest diseases from clinically silent diseases. Advanced cardiac imaging studies are crucial in the diagnostic pathway. In suspected isolated cardiac sarcoidosis, it's key to rule out alternative diagnoses. Therapeutic options can be divided into immunosuppressive agents, guideline-directed medical therapy, antiarrhythmic medications, device/ablation therapy, and heart transplantation.
Subject(s)
Cardiomyopathies , Heart Transplantation , Sarcoidosis , Humans , Cardiomyopathies/diagnosis , Cardiomyopathies/etiology , Cardiomyopathies/therapy , Sarcoidosis/diagnosis , Sarcoidosis/therapy , Diagnostic Imaging/methodsABSTRACT
BACKGROUND: A multistakeholder core outcome set created for asthma trials showed that asthma-specific quality of life (QoL) was a critically meaningful outcome. However, the definition and measurement methods were undetermined. The adverse effects (AEs) of corticosteroids may be a vital clinical trial outcome. Nevertheless, the AE burden from the patient perspective has not yet been elucidated in an asthma population. OBJECTIVE: To characterize patient burden of AEs in oral (OCS) and inhaled corticosteroids (ICS) and how this relates to QoL within an asthma population. METHODS: We used a convergent parallel mixed-methods design with quantitative surveys of known ICS and OCS AEs that were distributed through the Allergy & Asthma Network database, social channels, and the Asthma UK newsletter. Participants rated the AEs that were (1) most burdensome and (2) most desired to be eliminated. Qualitative interviews and focus groups were performed to better understand patient views on barriers reported in the quantitative data, and to identify patient-important barriers that were not a part of the quantitative survey. RESULTS: The 3 most burdensome AEs for OCS were bone mineral density, infectious complications, and weight gain, whereas weight gain was the most desired to be eliminated. The 3 most burdensome AEs for ICS were pneumonia, hoarse voice, and oral thrush, with concordant results for the most desired to be eliminated. In the focus groups, OCS AEs were concordant with quantitative findings. Focus groups identified unmeasured psychosocial effects, such as embarrassment. CONCLUSION: The most burdensome AEs may not be those that would cause patients to stop therapy. Furthermore, qualitative focus groups suggest a psychosocial burden associated with ICS, which needs further investigation.
Subject(s)
Anti-Asthmatic Agents , Asthma , Drug-Related Side Effects and Adverse Reactions , Humans , Quality of Life , Anti-Asthmatic Agents/adverse effects , Administration, Inhalation , Asthma/drug therapy , Asthma/chemically induced , Adrenal Cortex Hormones/adverse effects , Weight Gain , PerceptionABSTRACT
Mitochondrial dysfunction is linked to age-associated inflammation or inflammaging, but underlying mechanisms are not understood. Analyses of 700 human blood transcriptomes revealed clear signs of age-associated low-grade inflammation. Among changes in mitochondrial components, we found that the expression of mitochondrial calcium uniporter (MCU) and its regulatory subunit MICU1, genes central to mitochondrial Ca2+ (mCa2+) signaling, correlated inversely with age. Indeed, mCa2+ uptake capacity of mouse macrophages decreased significantly with age. We show that in both human and mouse macrophages, reduced mCa2+ uptake amplifies cytosolic Ca2+ oscillations and potentiates downstream nuclear factor kappa B activation, which is central to inflammation. Our findings pinpoint the mitochondrial calcium uniporter complex as a keystone molecular apparatus that links age-related changes in mitochondrial physiology to systemic macrophage-mediated age-associated inflammation. The findings raise the exciting possibility that restoring mCa2+ uptake capacity in tissue-resident macrophages may decrease inflammaging of specific organs and alleviate age-associated conditions such as neurodegenerative and cardiometabolic diseases.
Subject(s)
Calcium , Mitochondrial Membrane Transport Proteins , Mice , Animals , Humans , Mitochondrial Membrane Transport Proteins/genetics , Calcium/metabolism , Mitochondria/metabolism , Inflammation/metabolism , Macrophages/metabolism , Calcium-Binding Proteins/geneticsABSTRACT
There is expansive literature documenting the presence of health disparities, but there are disproportionately few studies describing interventions to reduce disparity. In this narrative review, we categorize interventions to reduce health disparity in pulmonary disease within the US health care system to support future initiatives to reduce disparity. We identified 211 articles describing interventions to reduce disparity in pulmonary disease related to race, income, or sex. We grouped the studies into the following four categories: biologic, educational, behavioral, and structural. We identified the following five main themes: (1) there were few interventional trials compared with the breadth of studies describing health disparities, and trials involving patients with asthma who were Black, low income, and living in an urban setting were overrepresented; (2) race or socioeconomic status was not an effective marker of individual pharmacologic treatment response; (3) telehealth enabled scaling of care, but more work is needed to understand how to leverage telehealth to improve outcomes in marginalized communities; (4) future interventions must explicitly target societal drivers of disparity, rather than focusing on individual behavior alone; and (5) individual interventions will only be maximally effective when specifically tailored to local needs. Much work has been done to catalog health disparities in pulmonary disease. Notable gaps in the identified literature include few interventional trials, the need for research in diseases outside of asthma, the need for high quality effectiveness trials, and an understanding of how to implement proven interventions balancing fidelity to the original protocol and the need to adapt to local barriers to care.
Subject(s)
Asthma , Delivery of Health Care , Humans , Social Class , Income , Asthma/therapy , Educational Status , Healthcare DisparitiesABSTRACT
While the epithelial cell cortex displays profound asymmetries in protein distribution and morphology along the apico-basal axis, the extent to which the cytoplasm is similarly polarized within epithelial cells remains relatively unexplored. We show that cytoplasmic organelles within C. elegans embryonic intestinal cells develop extensive apico-basal polarity at the time they establish cortical asymmetry. Nuclei and conventional endosomes, including early endosomes, late endosomes, and lysosomes, become polarized apically. Lysosome-related gut granules, yolk platelets, and lipid droplets become basally enriched. Removal of par-3 activity does not disrupt organelle positioning, indicating that cytoplasmic apico-basal asymmetry is independent of the PAR polarity pathway. Blocking the apical migration of nuclei leads to the apical positioning of gut granules and yolk platelets, whereas the asymmetric localization of conventional endosomes and lipid droplets is unaltered. This suggests that nuclear positioning organizes some, but not all, cytoplasmic asymmetries in this cell type. We show that gut granules become apically enriched when WHT-2 and WHT-7 function is disrupted, identifying a novel role for ABCG transporters in gut granule positioning during epithelial polarization. Analysis of WHT-2 and WHT-7 ATPase mutants is consistent with a WHT-2/WHT-7 heterodimer acting as a transporter in gut granule positioning. In wht-2(-) mutants, the polarized distribution of other organelles is not altered and gut granules do not take on characteristics of conventional endosomes that could have explained their apical mispositioning. During epithelial polarization wht-2(-) gut granules exhibit a loss of the Rab32/38 family member GLO-1 and ectopic expression of GLO-1 is sufficient to rescue the basal positioning of wht-2(-) and wht-7(-) gut granules. Furthermore, depletion of GLO-1 causes the mislocalization of the endolysosomal RAB-7 to gut granules and RAB-7 drives the apical mispositioning of gut granules when GLO-1, WHT-2, or WHT-7 function is disrupted. We suggest that ABC transporters residing on gut granules can regulate Rab dynamics to control organelle positioning during epithelial polarization.
Subject(s)
Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/metabolism , Cell Polarity , Epithelial Cells/metabolism , Intestinal Mucosa/metabolism , Organelles/metabolism , Animals , Caenorhabditis elegans/genetics , Caenorhabditis elegans Proteins/genetics , Organelles/geneticsABSTRACT
Rationale: Lower-income patients with sarcoidosis experience worse outcomes than those with higher incomes. The reasons for these disparities are not well understood. Objectives: To identify patient-reported barriers to and facilitators of self-empowered care among patients with sarcoidosis residing in high- and low-median-income zip-code areas. Methods: Patients with biopsy-proven sarcoidosis who had received pharmacologic treatment within the past year and who were cared for in a sarcoidosis clinic of a large, urban medical system were included. Focus groups were stratified by high- and low-median-income zip-code areas. Transcriptions were analyzed using grounded theory. Results: Five focus groups were created; two included patients living in zip-code areas with high median incomes ($84,263; interquartile range [IQR], $79,334-$89,795), and three included patients living in zip-code areas with low median incomes ($27,470; IQR, $22,412-27,597). Patients with sarcoidosis from low-income and high-income zip-code areas reported remarkably similar experiences. Patients reported that sarcoidosis was a burden owing to its disease manifestations and the adverse effects of treatment, which led to a compromised ability to perform their activities of daily living at home or at work. Reported barriers to care included perceived inadequate knowledge about sarcoidosis among providers, communication barriers with providers, and the high cost of treatment. Patients from low-income zip-code areas experienced discrimination related to race and income, which served to compound their mistrust. Patients sought to overcome these barriers through self-empowerment, including independent learning, self-advocacy, medication nonadherence, and use of alternative therapies. Conclusions: Patients with sarcoidosis who lived in high- and low-income zip-code areas expressed similar overall concerns regarding sarcoidosis care. However, patients from low-income zip-code areas more frequently expressed concerns about racial and income-based discrimination. Patients from both groups addressed these barriers through self-empowerment, which included not adhering to prescribed therapies. Future work should focus on the effects of culturally and socioeconomically congruent, community-engaged interventions for quality of life of patients with sarcoidosis.
Subject(s)
Health Services Accessibility , Sarcoidosis , Activities of Daily Living , Humans , Income , Quality of Life , Sarcoidosis/therapyABSTRACT
Phagocytes reallocate metabolic resources to kill engulfed pathogens, but the intracellular signals that rapidly switch the immunometabolic program necessary to fuel microbial killing are not understood. We report that macrophages use a fast two-step Ca2+ relay to meet the bioenergetic demands of phagosomal killing. Upon detection of a fungal pathogen, macrophages rapidly elevate cytosolic Ca2+ (phase 1), and by concurrently activating the mitochondrial Ca2+ (mCa2+) uniporter (MCU), they trigger a rapid influx of Ca2+ into the mitochondria (phase 2). mCa2+ signaling reprograms mitochondrial metabolism, at least in part, through the activation of pyruvate dehydrogenase (PDH). Deprived of mCa2+ signaling, Mcu-/- macrophages are deficient in phagosomal reactive oxygen species (ROS) production and defective at killing fungi. Mice lacking MCU in their myeloid cells are highly susceptible to disseminated candidiasis. In essence, this study reveals an elegant design principle that MCU-dependent Ca2+ signaling is an electrometabolic switch to fuel phagosome killing.
Subject(s)
Calcium/metabolism , Candida albicans/pathogenicity , Mitochondria/metabolism , Phagosomes/metabolism , Animals , Mice , Signal TransductionABSTRACT
ABC transporters couple ATP hydrolysis to the transport of substrates across cellular membranes. This protein superfamily has diverse activities resulting from differences in their cargo and subcellular localization. Our work investigates the role of the ABCG family member WHT-2 in the biogenesis of gut granules, a Caenorhabditis elegans lysosome-related organelle. In addition to being required for the accumulation of birefringent material within gut granules, WHT-2 is necessary for the localization of gut granule proteins when trafficking pathways to this organelle are partially disrupted. The role of WHT-2 in gut granule protein targeting is likely linked to its function in Rab GTPase localization. We show that WHT-2 promotes the gut granule association of the Rab32 family member GLO-1 and the endolysosomal RAB-7, identifying a novel function for an ABC transporter. WHT-2 localizes to gut granules where it could play a direct role in controlling Rab localization. Loss of CCZ-1 and GLO-3, which likely function as a guanine nucleotide exchange factor (GEF) for GLO-1, lead to similar disruption of GLO-1 localization. We show that CCZ-1, like GLO-3, is localized to gut granules. WHT-2 does not direct the gut granule association of the GLO-1 GEF and our results point to WHT-2 functioning differently than GLO-3 and CCZ-1 Point mutations in WHT-2 that inhibit its transport activity, but not its subcellular localization, lead to the loss of GLO-1 from gut granules, while other WHT-2 activities are not completely disrupted, suggesting that WHT-2 functions in organelle biogenesis through transport-dependent and transport-independent activities.
Subject(s)
ATP Binding Cassette Transporter, Subfamily G, Member 2/metabolism , ATP Binding Cassette Transporter, Subfamily G/genetics , ATP Binding Cassette Transporter, Subfamily G/metabolism , ATP Binding Cassette Transporter, Subfamily G, Member 2/genetics , ATP-Binding Cassette Transporters/genetics , Animals , Caenorhabditis elegans/metabolism , Caenorhabditis elegans Proteins/metabolism , Cytoplasmic Granules/metabolism , Endosomes/metabolism , Lysosomes/metabolism , Membrane Transport Proteins/genetics , Mutation , Organelle Biogenesis , Phenotype , Protein Transport/genetics , Vesicular Transport Proteins/genetics , rab GTP-Binding Proteins/genetics , rab GTP-Binding Proteins/metabolismABSTRACT
Rationale: Socioeconomic factors are associated with worse disease severity at presentation in sarcoidosis, but the relative importance of socioeconomic variables on morbidity and disease burden has not been fully elucidated.Objectives: To determine the association between income and sarcoidosis outcomes after controlling for socioeconomic and disease-related factors.Methods: Using the Sarcoidosis Advanced Registry for Cures database, we analyzed data from 2,318 patients with sarcoidosis in the United States to determine the effect of income and other variables on outcomes. We divided comorbidities arising after diagnosis into those likely related to steroid use and those likely related to sarcoidosis. We assessed the development of health-related, functional, and socioeconomic outcomes following the diagnosis of sarcoidosis.Measurements and Main Results: In multivariate analysis, low-income patients had significantly higher rates of new sarcoidosis-related comorbidities (<$35,000, odds ratio [OR], 2.4 [1.7-3.3]; $35,000-84,999, OR, 1.4 [1.1-1.9]; and ≥$85,000 [reference (Ref)]) and new steroid-related comorbidities (<$35,000, OR, 1.3 [0.9-2.0]; $35,000-84,999, OR, 1.5 [1.1-2.1]; and ≥$85,000 [Ref]), had lower health-related quality of life as assessed by the Sarcoidosis Health Questionnaire (P < 0.001), and experienced more impact on family finances (<$35,000, OR, 7.9 [4.9-12.7]; $35,000-84,999, OR, 2.7 [1.9-3.9]; and ≥$85,000 [Ref]). The use of supplemental oxygen, need for assistive devices, and job loss were more common in lower income patients. Development of comorbidities after diagnosis of sarcoidosis occurred in 63% of patients and were strong independent predictors of poor outcomes. In random forest modeling, income was consistently a leading predictor of outcome.Conclusions: These results suggest the burden from sarcoidosis preferentially impacts the economically disadvantaged.
Subject(s)
Cost of Illness , Hospitalization/statistics & numerical data , Income/statistics & numerical data , Oxygen Inhalation Therapy/statistics & numerical data , Quality of Life , Sarcoidosis/physiopathology , Unemployment/statistics & numerical data , Adult , Black or African American , Cardiomyopathies/epidemiology , Central Nervous System Diseases/epidemiology , Chronic Pain/epidemiology , Comorbidity , Depression/epidemiology , Fatigue Syndrome, Chronic/epidemiology , Female , Glucocorticoids/therapeutic use , Humans , Hypertension/epidemiology , Logistic Models , Male , Middle Aged , Mobility Limitation , Multivariate Analysis , Obesity/epidemiology , Odds Ratio , Poverty , Risk Factors , Sarcoidosis/drug therapy , Sarcoidosis/epidemiology , Self-Help Devices/statistics & numerical data , Sleep Apnea, Obstructive/epidemiology , Sleep Wake Disorders/epidemiology , Socioeconomic Factors , United States/epidemiology , White PeopleABSTRACT
Cardiac sarcoidosis (CS) is frequently difficult to treat. Infliximab (IFX) is useful for extracardiac sarcoidosis, but its use in CS has been limited due to concerns about cardiotoxicity and an FDA blackbox warning about use in heart failure. We reviewed 36 consecutive patients treated with infliximab for CS refractory to standard therapies. IFX was initiated for patients with refractory dysrhythmias, moderate to severe cardiomyopathy, and evidence of persistent F-18 fluorodeoxyglucose uptake on positron emission tomography scan, despite standard therapies. We compared the prednisone dose, ejection fraction (EF), and dysrhythmias before and after IFX therapy. The prednisone-equivalent steroid dose decreased from a median of 20 mg at initiation of infliximab to 7.5 at 6 months and 5 mg at 12 months postinitiation of infliximab (p <0.001). In the 25 patients with serial EF measurements, no statistically significant difference was detected in EF (41% at baseline, 42% at 6 months). Of the 16 patients with serial dysrhythmia data, there was a trend toward reduction of percent of patients with ventricular tachycardia (VT), from 32% at baseline, to 22% at 6 months and 19% at 12 months (pâ¯=â¯0.07). Adverse events were common, occurring in 6 of 36 patients, with 3 of 36 patients stopping infliximab for a prolonged period. In responder analysis, 24 patients improved in at least 1 of 3 outcome categories. In conclusion, infliximab may be useful for refractory cardiac sarcoidosis.
Subject(s)
Cardiomyopathies/drug therapy , Infliximab/administration & dosage , Sarcoidosis/drug therapy , Antirheumatic Agents/administration & dosage , Cardiomyopathies/diagnosis , Cardiomyopathies/physiopathology , Disease Progression , Dose-Response Relationship, Drug , Female , Follow-Up Studies , Glucocorticoids/administration & dosage , Humans , Male , Middle Aged , Positron-Emission Tomography/methods , Prednisone/administration & dosage , Sarcoidosis/diagnosis , Sarcoidosis/physiopathology , Stroke Volume/physiology , Treatment OutcomeABSTRACT
The matrix (MA) domain of the HIV-1 precursor Gag protein (PrGag) has been shown interact with the HIV-1 envelope (Env) protein, and to direct PrGag proteins to plasma membrane (PM) assembly sites by virtue of its affinity to phosphatidylinositol-4,5-bisphosphate (PI[4,5]P2). Unexpectedly, HIV-1 viruses with large MA deletions (ΔMA) have been shown to be conditionally infectious as long as they are matched with Env truncation mutant proteins or alternative viral glycoproteins. To characterize the interactions of wild type (WT) and ΔMA Gag proteins with PI(4,5)P2 and other acidic phospholipids, we have employed a set of lipid biosensors as probes. Our investigations showed marked differences in WT and ΔMA Gag colocalization with biosensors, effects on biosensor release, and association of biosensors with virus-like particles. These results demonstrate an alternative approach to the analysis of viral protein-lipid associations, and provide new data as to the lipid compositions of HIV-1 assembly sites.
Subject(s)
Gene Products, gag/metabolism , HIV-1/physiology , Mutant Proteins/metabolism , Phosphatidylinositol 4,5-Diphosphate/metabolism , Virus Assembly , Biosensing Techniques , Gene Products, gag/genetics , HIV-1/genetics , Mutant Proteins/genetics , Protein Binding , Sequence DeletionABSTRACT
BACKGROUND: Mutations of the human K-Ras 4B (K-Ras) G protein are associated with a significant proportion of all human cancers. Despite this fact, a comprehensive analysis of K-Ras interactions is lacking. Our investigations focus on characterization of the K-Ras interaction network. MATERIALS AND METHODS: We employed a biotin ligase-tagging approach, in which tagged K-Ras proteins biotinylate neighbor proteins in a proximity-dependent fashion, and proteins are identified via mass spectrometry (MS) sequencing. RESULTS: In transfected cells, a total of 748 biotinylated proteins were identified from cells expressing biotin ligase-tagged K-Ras variants. Significant differences were observed between membrane-associated variants and a farnesylation-defective mutant. In pancreatic cancer cells, 56 K-Ras interaction partners were identified. Most of these were cytoskeletal or plasma membrane proteins, and many have been identified previously as potential cancer biomarkers. CONCLUSION: Biotin ligase tagging offers a rapid and convenient approach to the characterization of K-Ras interaction networks.
Subject(s)
Carbon-Nitrogen Ligases/metabolism , Escherichia coli Proteins/metabolism , Oncogene Protein p21(ras)/metabolism , Repressor Proteins/metabolism , Animals , Biotinylation , Carbon-Nitrogen Ligases/genetics , Escherichia coli Proteins/genetics , HEK293 Cells , Humans , Mice , Mutation , NIH 3T3 Cells , Oncogene Protein p21(ras)/genetics , Protein Binding , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Repressor Proteins/geneticsABSTRACT
We have analyzed a set of quinolinequinones with respect to their reactivities, cytotoxicities, and anti-HIV-1 properties. Most of the quinolinequinones were reactive with glutathione, and several acted as sulfhydryl crosslinking agents. Quinolinequinones inhibited binding of the HIV-1 matrix protein to RNA to varying degrees, and several quinolinequinones showed the capacity to crosslink HIV-1 matrix proteins in vitro, and HIV-1 structural proteins in virus particles. Cytotoxicity assays yielded quinolinequinone CC50 values in the low micromolar range, reducing the potential therapeutic value of these compounds. However, one compound, 6,7-dichloro-5,8-quinolinequinone potently inactivated HIV-1, suggesting that quinolinequinones may prove useful in the preparation of inactivated virus vaccines or for other virucidal purposes.
Subject(s)
Anti-HIV Agents/pharmacology , HIV-1/drug effects , Quinolines/pharmacology , Anti-HIV Agents/chemical synthesis , Anti-HIV Agents/chemistry , Cell Proliferation/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , HEK293 Cells , Humans , Microbial Sensitivity Tests , Molecular Structure , Nuclear Matrix/drug effects , Quinolines/chemical synthesis , Quinolines/chemistry , RNA, Viral/antagonists & inhibitors , Structure-Activity RelationshipABSTRACT
AIMS OF THE STUDY: We aimed to determine the benefit of an expanded use of TH. We also described the impact of a targeted temperature management on outcomes at discharge. DATA SOURCES: We identified studies by searching MEDLINE, EMBASE and Cochrane Library databases. We included RCTs and observational studies restricted to those reporting achieved temperature during TH after OHCA. No other patient, cardiac arrest or hypothermia protocol restrictions were applied. Outcomes of interest were hospital mortality and neurological outcome at discharge. Appropriate risk of bias assessment for meta-analyzed studies was conducted. Studies contrasting hypothermia and normothermia outcomes were meta-analyzed using a random-effect model. Outcomes of cooling arms, obtained from enrolled studies, were pooled and compared across achieved temperatures. RESULTS: Search strategy yielded 32,275 citations of which 24 articles met inclusion criteria. Eleven studies were meta-analyzed. The use of TH after OHCA, even within an expanded use, decreased the mortality (OR 0.51, 95%CI [0.41-0.64]) and improved the odds of good neurological outcome (OR 2.48, 95%CI [1.91-3.22]). No statistical heterogeneity was found for either mortality (I2=4.0%) or neurological outcome (I2=0.0%). No differences in hospital mortality (p=0.86) or neurological outcomes at discharge (p=0.32) were found when pooled outcomes of 34 hypothermia arms grouped by cooling temperature were compared. CONCLUSION: The use of TH after OHCA is associated with a survival and neuroprotective benefit, even when including patients with non-shockable rhythms, more lenient downtimes, unwitnessed arrest and/or persistent shock. We found no evidence to support one specific temperature over another during hypothermia.