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Objective To determine whether serum fructosamine correlates with glycemic control and clinical outcomes in patients being screened for cystic fibrosis-related diabetes (CFRD). Methods Fructosamine and percent predicted forced expiratory volume in 1 s (FEV 1 ) were measured in patients undergoing a 2 h oral glucose tolerance test (OGTT) for CFRD screening. Fractional serum fructosamine (FSF) was calculated as fructosamine/total protein. Results FSF exhibited a positive correlation with 2 h OGTT results (r 2 = 0.3201, p = 0.009), and ROC curve analysis suggested that FSF can identify patients with an abnormal OGTT (AUC = 0.840, p = 0.0002). FSF also exhibited a negative correlation with FEV 1 (r 2 = 0.3732, p = 0.035). Patients with FSF ≥ 3.70 μmol/g had significantly lower FEV 1 (median 47%) compared to those with FSF < 3.70 μmol/g (median 90%; p = 0.015). Conclusions FSF correlated with both OGTT results and FEV 1 , and reliably identified patients with abnormal OGTT results. This simple blood test shows potential as an effective tool in CFRD screening. [ABSTRACT FROM AUTHOR]

It has been postulated that during human fetal development, all cells of the lung epithelium derive from embryonic, endodermal, NK2 homeobox 1-expressing (NKX2-1+) precursor cells. However, this hypothesis has not been formally tested owing to an inability to purify or track these progenitors for detailed characterization. Here we have engineered and developmentally differentiated NKX2-1GFP reporter pluripotent stem cells (PSCs) in vitro to generate and isolate human primordial lung progenitors that express NKX2-1 but are initially devoid of differentiated lung lineage markers. After sorting to purity, these primordial lung progenitors exhibited lung epithelial maturation. In the absence of mesenchymal coculture support, this NKX2-1+ population was able to generate epithelial-only spheroids in defined 3D cultures. Alternatively, when recombined with fetal mouse lung mesenchyme, the cells recapitulated epithelial-mesenchymal developing lung interactions. We imaged these progenitors in real time and performed time-series global transcriptomic profiling and single-cell RNA sequencing as they moved through the earliest moments of lung lineage specification. The profiles indicated that evolutionarily conserved, stage-dependent gene signatures of early lung development are expressed in primordial human lung progenitors and revealed a CD47hiCD26lo cell surface phenotype that allows their prospective isolation from untargeted, patient-specific PSCs for further in vitro differentiation and future applications in regenerative medicine. [ABSTRACT FROM AUTHOR]

Arginine methyltransferases (RMTs) catalyze the methylation of arginine residues on proteins. We examined the effects of log-phase growth, stationary-phase growth, and heat shock on the formation of methylarginines on yeast proteins to determine if the conditions favor a particular type of methylation. Utilizing linear ion trap mass spectrometry, we identify methylarginines in wild-type and RMT deletion yeast strains using secondary product ion scans (MS), and quantify the methylarginines using multiple reaction monitoring (MRM). Employing MS and isotopic incorporation, we demonstrate for the first time that Nη1, Nη2-dimethylarginine (sDMA) is present on yeast proteins, and make a detailed structural determination of the fragment ions from the spectra. Nη-monomethylarginine (ηMMA), Nδ-monomethylarginine (δMMA), Nη1, Nη1-dimethylarginine (aDMA), and sDMA were detected in RMT deletion yeast using MS and MRM with and without isotopic incorporation, suggesting that additional RMT enzymes remain to be discovered in yeast. The concentrations of ηMMA and δMMA decreased by half during heat shock and stationary phase compared to log-phase growth of wild-type yeast, whereas sDMA increased by as much as sevenfold and aDMA decreased by 11-fold. Therefore, upon entering stressful conditions like heat shock or stationary-phase growth, there is a net increase in sDMA and decreases in aDMA, ηMMA, and δMMA on yeast proteins. [ABSTRACT FROM AUTHOR]

Abstract: Protein arginine methylation is one of the epigenetic modifications to proteins that is studied in yeast and is known to be involved in a number of human diseases. All eukaryotes produce Nη-monomethylarginine (ηMMA), asymmetric Nη1, Nη1-dimethylarginine (aDMA), and most produce symmetric Nη1, Nη2-dimethylarginine (sDMA) on proteins, but only yeast produce Nδ-monomethylarginine (δMMA). It has proven difficult to differentiate among all of these methylarginines using mass spectrometry. Accordingly, we demonstrated that the two forms of MMA have indistinguishable primary product ion spectra. However, the secondary product ion spectra of δMMA and ηMMA exhibited distinct patterns of ions. Using incorporation of deuterated methyl-groups in yeast, we determined which secondary product ions were methylated and their structures. Utilizing distinct secondary product ions, a triple quadrupole multiple reaction monitoring cubed (MRM3) assay was developed to measure δMMA, ηMMA, sDMA and aDMA derived from hydrolyzed protein. As a proof-of-concept, δMMA and ηMMA were measured using the MRM3 method in wild type and mutant strains of Saccharomyces cerevisiae and compared to the total MMA measured using an existing assay. The MRM3 assay represents the only method to directly quantify δMMA and the only method to simultaneously quantify all yeast methylarginines. [Copyright &y& Elsevier]

Purpose: The spine, hip, and knee are anatomically and biomechanically connected. Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are commonly employed to treat degenerative changes in the hip and knee, while fusion is used for spine degeneration. Spine deformity correction results in changes in sagittal alignment and pelvic parameters, and patients with stiff spines have higher rates of THA dislocation and revision due to instability. The goal of this study was to determine the prevalence of total joint arthroplasty (TJA) in adult spinal deformity (ASD) patients at our institution., Methods: Following Institutional Review Board approval, we retrospectively reviewed a list of cases performed by the senior author from 4/2017 to 5/2021. Patients > 18 years old undergoing preoperative evaluation for symptomatic lumbar degeneration or ASD were included. Patients < 18 years old, those diagnosed with adolescent idiopathic scoliosis, and non-fusion cases were excluded. Perioperative full-length standing EOS images were examined for the presence or absence of THA, TKA, or both. Demographic data was collected from patient electronic medical records, and statistical analyses were completed., Results: 572 consecutive cases were reviewed, and 322 were excluded. 250 cases (97M:153F) were included in the final analysis, with a mean age of 61.8 ± 11.2 years. A total of 74 patients had a TJA (29.4%). THA was present in 41 patients (16.4%), and TKA was present in 49 patients (19.6%). Males had a higher prevalence of TJA, THA, and TKA (29.9%, 16.5%, and 21.6%) than females (29.4%, 16.3%, and 18.3%)., Conclusions: This study revealed a high prevalence TJA rate of 29.4% in ASD at our institution. This rate surpasses the prevalence rate reported among the general population in previous studies. High prevalence of patients with ASD and TJA may merit special surgical consideration., (© 2024. The Author(s), under exclusive licence to Scoliosis Research Society.)

Targeted antineoplastic immunotherapies have achieved remarkable clinical outcomes. However, resistance to these therapies due to target absence or antigen shedding limits their efficacy and excludes tumours from candidacy. To address this limitation, here we engineer an oncolytic rhabdovirus, vesicular stomatitis virus (VSVΔ51), to express a truncated targeted antigen, which allows for HER2-targeting with trastuzumab. The truncated HER2 (HER2T) lacks signaling capabilities and is efficiently expressed on infected cell surfaces. VSVΔ51-mediated HER2T expression simulates HER2-positive status in tumours, enabling effective treatment with the antibody-drug conjugate trastuzumab emtansine in vitro, ex vivo, and in vivo. Additionally, we combine VSVΔ51-HER2T with an oncolytic vaccinia virus expressing a HER2-targeted T-cell engager. This dual-virus therapeutic strategy demonstrates potent curative efficacy in vivo in female mice using CD3+ infiltrate for anti-tumour immunity. Our findings showcase the ability to tailor the tumour microenvironment using oncolytic viruses, thereby enhancing compatibility with "off-the-shelf" targeted therapies., (© 2024. The Author(s).)

Background: Sacral (S1) pedicle screw misplacement in posterior percutaneous fixation (PPF) can be related to anatomical variability and a lack of reliable radiographic landmarks. This study highlights a reproducible anatomical landmark (the "V" sign) for the safe localization of the S1 pedicle entry point under fluoroscopy., Methods: Human cadavers (n = 14) were dissected for the anatomical description of the "V" landmark and its relationship with the entry point of the S1 pedicle screw. The "V" landmark was defined medially by the lateral border of the superior articulating process of S1 and laterally by the posterior projection of the sacral ala. The mean distance was measured between the bottom point of the "V" landmark and the anatomical entry point to the S1 pedicle (V-S1 entry point distance). A similar measurement was conducted on computed tomography (CT) scans of 135 patients who underwent PPF using the "V" sign as a landmark for S1 pedicle screw placement (270 screws). These were retrospectively evaluated for appropriateness of S1 screw entry points and for proper S1 screw alignment and breaches., Results: In the 14 cadavers, irrespective of the laterality and sex, the V-S1 entry point distance averaged 11.7 mm. On the medial-lateral axis, all entry points converged within 2 mm of a vertical line intersecting the base of the "V." Additionally, the CT scan analysis (135 patients, 270 screws) revealed an optimal entry point for 100% of the screws and a 3.3% (n = 9 screws) breach rate. Six of the 9 identified breaches were minor, and only 1 (0.4% of the 270 screws) warranted revision., Conclusions: The "V" sign serves as a reliable anatomical and radiographic landmark for identifying the S1 pedicle entry point under fluoroscopic guidance. This landmark can help surgeons overcome the radiographic ambiguity of the sacral anatomy and ultimately reduces the rate of S1 pedicle screw misplacement., Level of Evidence: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJSOA/A555)., (Copyright © 2023 The Authors. Published by The Journal of Bone and Joint Surgery, Incorporated. All rights reserved.)

Iridescence is a taxonomically widespread form of structural coloration that produces often intense hues that change with the angle of viewing. Its role as a signal has been investigated in multiple species, but recently, and counter-intuitively, it has been shown that it can function as camouflage. However, the property of iridescence that reduces detectability is, as yet, unclear. As viewing angle changes, iridescent objects change not only in hue but also in intensity, and many iridescent animals are also shiny or glossy; these "specular reflections," both from the target and background, have been implicated in crypsis. Here, we present a field experiment with natural avian predators that separate the relative contributions of color and gloss to the "survival" of iridescent and non-iridescent beetle-like targets. Consistent with previous research, we found that iridescent coloration, and high gloss of the leaves on which targets were placed, enhance survival. However, glossy targets survived less well than matt. We interpret the results in terms of signal-to-noise ratio: specular reflections from the background reduce detectability by increasing visual noise. While a specular reflection from the target attracts attention, a changeable color reduces the signal because, we suggest, normally, the color of an object is a stable feature for detection and identification., (© The Author(s) 2023. Published by Oxford University Press on behalf of the International Society for Behavioral Ecology.)

Photosynthetic organisms frequently experience abiotic stress that restricts their growth and development. Under such circumstances, most absorbed solar energy cannot be used for CO2 fixation and can cause the photoproduction of reactive oxygen species (ROS) that can damage the photosynthetic reaction centers of PSI and PSII, resulting in a decline in primary productivity. This work describes a biological "switch" in the green alga Chlamydomonas reinhardtii that reversibly restricts photosynthetic electron transport (PET) at the cytochrome b6f (Cyt b6f) complex when the capacity for accepting electrons downstream of PSI is severely limited. We specifically show this restriction in STARCHLESS6 (sta6) mutant cells, which cannot synthesize starch when they are limited for nitrogen (growth inhibition) and subjected to a dark-to-light transition. This restriction represents a form of photosynthetic control that causes diminished electron flow to PSI and thereby prevents PSI photodamage but does not appear to rely on a ΔpH. Furthermore, when electron flow is restricted, the plastid alternative oxidase (PTOX) becomes active, functioning as an electron valve that dissipates some excitation energy absorbed by PSII and allows the formation of a proton motive force (PMF) that would drive some ATP production (potentially sustaining PSII repair and nonphotochemical quenching [NPQ]). The restriction at the Cyt b6f complex can be gradually relieved with continued illumination. This study provides insights into how PET responds to a marked reduction in availability of downstream electron acceptors and the protective mechanisms involved., Competing Interests: Conflict of interest statement. The authors declare that they have no conflicts of interest with respect to the research, authorship, financial nature, and/or publication of this article., (© American Society of Plant Biologists 2023. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

While primary bone malignancies make up just 0.2% of all cancers, osteosarcoma (OS) is the third most common cancer in adolescents. Due to its highly complex and heterogeneous tumor microenvironment (TME), OS has proven difficult to treat. There has been little to no improvement in therapy for this disease over the last 40 years. Even the recent success of immunotherapies in other blood-borne and solid malignancies has not translated to OS. With frequent recurrence and lung metastases continuing to pose a challenge in the clinic, recent advancements in molecular profiling, such as single-cell RNA sequencing (scRNA-seq), have proven useful in identifying novel biomarkers of OS tumors while providing new insight into this TME that could potentially lead to new therapeutic options. This review combines the analyses of over 150,000 cells from 18 lesions ranging from primary, recurrent, and metastatic OS lesions, revealing distinct cellular populations and gene signatures that exist between them. Here, we detail these previous findings and ultimately convey the intratumoral heterogeneity that exists within OS tumor specimens., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Author(s).)

Slipped Capital Femoral Epiphysis (SCFE) is a physeal disorder of the proximal femur. Misdiagnosis and late treatment are associated with poorer outcomes. The epidemiology and delays in treatment of the disease between 1968 and 2018 were investigated in North Trinidad. The number of cases presenting annually has increased over the decades and the incidence between 2008-2018 was 2.2 cases per 100 000 per year. Almost 70% of cases were above the 95 th percentile for body weight. Delay in treatment from onset of symptoms was 278 ± 258 days. Awareness of the risk factors and clinical presentation of SCFE may facilitate early diagnosis and treatment, and prevent severe hip disability in adulthood.

Cystic fibrosis is a monogenic lung disease caused by dysfunction of the cystic fibrosis transmembrane conductance regulator anion channel, resulting in significant morbidity and mortality. The progress in elucidating the role of CFTR using established animal and cell-based models led to the recent discovery of effective modulators for most individuals with CF. However, a subset of individuals with CF do not respond to these modulators and there is an urgent need to develop novel therapeutic strategies. In this study, we generate a panel of airway epithelial cells using induced pluripotent stem cells from individuals with common or rare CFTR variants representative of three distinct classes of CFTR dysfunction. To measure CFTR function we adapt two established in vitro assays for use in induced pluripotent stem cell-derived airway cells. In both a 3-D spheroid assay using forskolin-induced swelling as well as planar cultures composed of polarized mucociliary airway epithelial cells, we detect genotype-specific differences in CFTR baseline function and response to CFTR modulators. These results demonstrate the potential of the human induced pluripotent stem cell platform as a research tool to study CF and in particular accelerate therapeutic development for CF caused by rare variants., (© 2022. The Author(s).)

Objective During the COVID-19 pandemic, certain precautionary measures were implemented to limit its effect, including the cancellation of clinics and elective surgical lists. To determine the impact, if any, of the pandemic on the running of a neurosurgical service, an audit was performed on the volume of referrals, admissions and type of surgeries performed at a tertiary institute in a low-resource setting. Methods An audit of the neurosurgical department's database was performed on the number of referrals, admissions, surgical procedures, and types of procedures done at the San Fernando General Hospital. This was divided into two 15-month periods, pre-pandemic (January 1, 2019 to March 31, 2020) and intra-pandemic (April 1, 2020 - June 30, 2021). Results During the pre-pandemic period (January 1, 2019 - March 31, 2020), 2,597 patients were referred to the service and 309 major procedures were performed. Two thousand and forty-two patients were referred during the intra-pandemic (April 4, 2020 - June 30, 2021) period, with 354 surgeries performed. More external ventricular drains (29 vs 50), craniotomies for trauma (73 vs 98), anterior cervical fusion (42 vs 47), lumbar fusions (9 vs 12), ventriculo-peritoneal shunts (16 vs 19) and aneurysm clipping (10 vs 13) were done during the intra-pandemic period. Conclusion Although elective surgical procedures and clinics were reduced, the number of patients seen and total procedures performed did not vary significantly. The neurosurgical pathology encountered remained constant during the pandemic. This shows the importance of maintaining a fully functional neurosurgical service, as we continue to adapt to the COVID-19 pandemic., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Seetahal-Maraj et al.)

Objective: Electronic consultations (e-consults) are clinician-to-clinician communications that may obviate face-to-face specialist visits. E-consult programs have spread within the US and internationally despite limited data on outcomes. We conducted a systematic review of the recent peer-reviewed literature on the effect of e-consults on access, cost, quality, and patient and clinician experience and identified the gaps in existing research on these outcomes., Materials and Methods: We searched 4 databases for empirical studies published between 1/1/2015 and 2/28/2019 that reported on one or more outcomes of interest. Two investigators reviewed titles and abstracts. One investigator abstracted information from each relevant article, and another confirmed the abstraction. We applied the GRADE criteria for the strength of evidence for each outcome., Results: We found only modest empirical evidence for effectiveness of e-consults on important outcomes. Most studies are observational and within a single health care system, and comprehensive assessments are lacking. For those outcomes that have been reported, findings are generally positive, with mixed results for clinician experience. These findings reassure but also raise concern for publication bias., Conclusion: Despite stakeholder enthusiasm and encouraging results in the literature to date, more rigorous study designs applied across all outcomes are needed. Policy makers need to know what benefits may be expected in what contexts, so they can define appropriate measures of success and determine how to achieve them., (Published by Oxford University Press on behalf of the American Medical Informatics Association 2019. This work is written by US Government employees and is in the public domain in the US.)

Alveolar epithelial type II cells (AEC2s) are the facultative progenitors of lung alveoli and serve as the surfactant-producing cells of air-breathing organisms. Although primary human AEC2s are difficult to maintain stably in cell cultures, recent advances have facilitated the derivation of AEC2-like cells from human pluripotent stem cells (hPSCs) in vitro. Here, we provide a detailed protocol for the directed differentiation of hPSCs into self-renewing AEC2-like cells that can be maintained for up to 1 year in culture as epithelial-only spheres without the need for supporting mesenchymal feeder cells. The month-long protocol requires recapitulation of the sequence of milestones associated with in vivo development of the distal lung, beginning with differentiation of cells into anterior foregut endoderm, which is followed by their lineage specification into NKX2-1 + lung progenitors and then distal/alveolar differentiation to produce progeny that express transcripts and possess functional properties associated with AEC2s.

Goals: To determine whether diabetic patients with hepatitis C virus (HCV) treated with direct-acting antiviral agents have improved diabetes, accounting for change in both hemoglobin A1c (HbA1c) and diabetes medications, and whether any improvement was sustained., Background: HCV infection is associated with an increased risk of diabetes, with improvement in glycemic control after eradication. There remains uncertainty about the durability and magnitude of this effect., Study: HbA1c and diabetes medications were recorded at 6-month intervals for 1.5 years pretreatment and posttreatment for 122 patients. Subjects were classified as having improved diabetes if there was a decrease in HbA1c≥0.5% with no increase in diabetes medications or a decrease in diabetes medications with a stable HbA1c., Results: HbA1c at the nearest time point before treatment was 8.4%±1.9%, compared with 7.8%±1.7% after treatment, a mean difference of 0.6% [95% CI (0.2, 0.9), P<0.01]. A linear mixed effects model incorporating each subject's repeated measurements over time also demonstrated a reduction after treatment of 0.5% [95% CI, (0.3, 0.8), P<0.001]. Accounting for both HbA1c and diabetes medications, 42 of 122 (34%) had an improvement in diabetes after HCV treatment, and 20 of 28 (71%) of these subjects sustained improvement at 1.5 years follow-up. Prescription of insulin was associated with improved diabetes., Conclusions: Treatment of HCV with direct-acting antiviral agents was associated with improved diabetes in a significant portion of patients with an average reduction in HbA1c of clinically significant magnitude. Among responders, this effect was sustained over 1.5 years of follow-up.

Hyperinsulinemia is strongly associated with type 2 diabetes. Racial and ethnic minority populations are disproportionately affected by diabetes and obesity-related complications. This mini-review provides an overview of the genetic and environmental factors associated with hyperinsulinemia with a focus on racial and ethnic differences and its metabolic consequences. The data used in this narrative review were collected through research in PubMed and reference review of relevant retrieved articles. Insulin secretion and clearance are regulated processes that influence the development and progression of hyperinsulinemia. Environmental, genetic, and dietary factors are associated with hyperinsulinemia. Certain pharmacotherapies for obesity and bariatric surgery are effective at mitigating hyperinsulinemia and are associated with improved metabolic health. Hyperinsulinemia is associated with many environmental and genetic factors that interact with a wide network of hormones. Recent studies have advanced our understanding of the factors affecting insulin secretion and clearance. Further basic and translational work on hyperinsulinemia may allow for earlier and more personalized treatments for obesity and metabolic diseases., Competing Interests: Disclosure Summary: C.M.A. reports grants from Aspire Bariatrics, the Vela Foundation, Coherence Laboratory, Energesis, NIH, and PCORI; grants and personal fees from GI Dynamics, Takeda, Novo Nordisk, and Gelesis; and personal fees from Orexigen, EnteroMedics, Nutrisystem, Zafgen, Sanofi-Aventis, Scientific Intake, Xeno Biosciences, Rhythm Pharmaceuticals, Eisai, and Bariatrix Nutrition and other fees from Science-Smart LLC, outside the submitted work. The remaining authors have nothing to disclose.Data sharing is not applicable to this article as no data sets were generated or analyzed during the current study.

Objective: Weight-management medications (WMM) are recommended for the treatment of obesity. This study examined characteristics associated with initial receipt of WMM among eligible veterans in the first year following enrollment in the Veterans Health Administration (VHA) MOVE! behavioral weight-management program., Methods: We conducted a retrospective cohort study of VHA patients with obesity or overweight and obesity-related comorbidities who enrolled in MOVE! from October 2013 to September 2016 (N = 153,939). Multivariable logistic regression models estimated predictors of having a filled prescription for WMM and for orlistat., Results: A total of 1.1% of these veterans received WMM. The most common WMM included orlistat (70.4%), phentermine/topiramate (11.2%), and bupropion/naltrexone (9.7%). Female sex, higher BMI, obstructive sleep apnea, osteoarthritis, depression, lower back pain, and alcohol abuse were associated with greater odds of use of WMM, whereas age over 65 years, Hispanic ethnicity, and required co-payments were associated with lower odds. Among patients receiving WMM, older age, black race, female sex, higher BMI, cardiovascular disease, lower back pain, and congestive heart failure were associated with use of orlistat versus any other WMM., Conclusions: Of patients engaged in MOVE! in the VHA, 1.1% received WMM. WMM are underutilized among veterans. Additional research is needed to understand barriers to incorporating WMM into comprehensive obesity treatment plans., (© 2019 The Obesity Society.)

Environmental stresses dramatically impact the balance between the production of photosynthetically derived energetic electrons and Calvin-Benson-Bassham cycle (CBBC) activity; an imbalance promotes accumulation of reactive oxygen species and causes cell damage. Hence, photosynthetic organisms have developed several strategies to route electrons toward alternative outlets that allow for storage or harmless dissipation of their energy. In this work, we explore the activities of three essential outlets associated with Chlamydomonas reinhardtii photosynthetic electron transport: ( i ) reduction of O 2 to H 2 O through flavodiiron proteins (FLVs) and ( ii ) plastid terminal oxidases (PTOX) and ( iii ) the synthesis of starch. Real-time measurements of O 2 exchange have demonstrated that FLVs immediately engage during dark-to-light transitions, allowing electron transport when the CBBC is not fully activated. Under these conditions, we quantified maximal FLV activity and its overall capacity to direct photosynthetic electrons toward O 2 reduction. However, when starch synthesis is compromised, a greater proportion of the electrons is directed toward O 2 reduction through both the FLVs and PTOX, suggesting an important role for starch synthesis in priming/regulating CBBC and electron transport. Moreover, partitioning energized electrons between sustainable (starch; energetic electrons are recaptured) and nonsustainable (H 2 O; energetic electrons are not recaptured) outlets is part of the energy management strategy of photosynthetic organisms that allows them to cope with the fluctuating conditions encountered in nature. Finally, unmasking the repertoire and control of such energetic reactions offers new directions for rational redesign and optimization of photosynthesis to satisfy global demands for food and other resources., Competing Interests: The authors declare no conflict of interest., (Copyright © 2019 the Author(s). Published by PNAS.)

Background: Cardiac troponin I (cTnI) 99th percentile cutoffs, used in the diagnosis of acute myocardial infarction, are not standardized across cTnI assays. We compared 3 point-of-care (POC) and 1 central laboratory contemporary cTnI assays against the Abbott high-sensitivity (hs) cTnI to evaluate the analytical concordance and the feasibility of using a single cutoff value for all assays., Methods: Fresh blood samples collected from 102 inpatients in the coronary care unit were measured on central laboratory instruments (Beckman Coulter DxI AccuTnI+3 TnI, Abbott Architect hs-TnI) and cTnI POC analyzers (Alere Triage Troponin I, Radiometer AQT90, Abbott i-STAT). Agreement and correlation between the contemporary cTnI assays and hs-cTnI assay were assessed using regression analysis. Proportional bias was assessed using Bland-Altman plots. Concordance between the contemporary cTnI and hs-cTnI assays was determined by diagnostic contingency tables at specific cutoffs., Results: Most POC cTnI assays had excellent correlation with the Abbott hs-cTnI method ( r 2 = 0.955-0.970) except for Alere Triage ( r 2 = 0.617), while proportional bias is evident between all cTnI assays. Overall concordance between POC contemporary cTnI assays and hs-cTnI assay was 80% to 90% at their respective 99th percentile cutoffs. The concordance increased to 90% to 95% when a fixed cutoff of 0.03 to 0.05 ng/mL was used across the assays., Conclusions: This study demonstrates poor analytical concordance between cTnI assays at the 99th percentile and supports the notion of a single clinical decision limit for cTnI and consequently standardization of diagnostic protocols despite the analytical differences among these assays., (© 2018 American Association for Clinical Chemistry.)

Sloths are canopy-dwelling inhabitants of American neotropical rainforests that exhibit suspensory behaviors. These abilities require both strength and muscular endurance to hang for extended periods of time; however, the skeletal muscle mass of sloths is reduced, thus requiring modifications to muscle architecture and leverage for large joint torque. We hypothesize that intrinsic muscle properties are also modified for fatigue resistance and predict a heterogeneous expression of slow/fast myosin heavy chain (MHC) fibers that utilize oxidative metabolic pathways for economic force production. MHC fiber type distribution and energy metabolism in the forelimb muscles of three-toed ( Bradypus variegatus, n = 5) and two-toed ( Choloepus hoffmanni, n = 4) sloths were evaluated using SDS-PAGE, immunohistochemistry, and enzyme activity assays. The results partially support our hypothesis by a primary expression of the slow MHC-1 isoform as well as moderate expression of fast MHC-2A fibers, whereas few hybrid MHC-1/2A fibers were found in both species. MHC-1 fibers were larger in cross-sectional area (CSA) than MHC-2A fibers and comprised the greatest percentage of CSA in each muscle sampled. Enzyme assays showed elevated activity for the anaerobic enzymes creatine kinase and lactate dehydrogenase compared with low activity for aerobic markers citrate synthase and 3-hydroxyacetyl CoA dehydrogenase. These findings suggest that sloth forelimb muscles may rely heavily on rapid ATP resynthesis pathways, and lactate accumulation may be beneficial. The intrinsic properties observed match well with suspensory requirements, and these modifications may have further evolved in unison with low metabolism and slow movement patterns as means to systemically conserve energy. NEW & NOTEWORTHY Myosin heavy chain (MHC) fiber type and fiber metabolic properties were evaluated to understand the ability of sloths to remain suspended for extended periods without muscle fatigue. Broad distributions of large, slow MHC-1 fibers as well as small, fast MHC-2A fibers are expressed in sloth forelimbs, but muscle metabolism is generally not correlated with myosin fiber type or body size. Sloth muscles rely on rapid, anaerobic pathways to resist fatigue and sustain force production.

Purpose of Review: We review the underlying mechanisms and potential benefits of intermittent fasting (IF) from animal models and recent clinical trials., Recent Findings: Numerous variations of IF exist, and study protocols vary greatly in their interpretations of this weight loss trend. Most human IF studies result in minimal weight loss and marginal improvements in metabolic biomarkers, though outcomes vary. Some animal models have found that IF reduces oxidative stress, improves cognition, and delays aging. Additionally, IF has anti-inflammatory effects, promotes autophagy, and benefits the gut microbiome. The benefit-to-harm ratio varies by model, IF protocol, age at initiation, and duration. We provide an integrated perspective on potential benefits of IF as well as key areas for future investigation. In clinical trials, caloric restriction and IF result in similar degrees of weight loss and improvement in insulin sensitivity. Although these data suggest that IF may be a promising weight loss method, IF trials have been of moderate sample size and limited duration. More rigorous research is needed.

Protein sparing therapies were developed to mitigate the harms associated with protein-calorie malnutrition and nitrogen losses induced by either acute illness or hypocaloric diets in patients with obesity. We review the development of protein sparing therapies in illness and obesity with a focus on the pioneering contributions of George Blackburn, MD, PhD. He recognized that protein-calorie malnutrition is a common and serious clinical condition and developed new approaches to its treatment in hospitalized patients. His work with stable isotopes and with animal models provided answers about the physiological nutritional requirements and metabolic changes across a spectrum of conditions with varying degrees of stress and catabolism. This led to improvements in enteral and parenteral nutrition for patients with acute illness. Blackburn also demonstrated that lean body mass can be preserved during weight loss with carefully designed very low calorie treatments which became known as the protein sparing modified fast (PSMF). We review the role of the PSMF as part of the comprehensive management of obesity., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Protein electrophoresis is commonly used as an aid in the diagnosis of monoclonal gammopathies and is performed in many laboratories in Canada and throughout the world. However, unlike many other diagnostic tests, there is limited guidance for standardization and neither guidance nor specific recommendations for clinical reporting of serum (SPE) or urine (UPE) protein electrophoresis and immunotyping available in the literature. Therefore, a Canadian effort was undertaken to recommend standards that cover all aspects of clinical reporting with an ultimate goal towards reporting standardization. The Canadian Society of Clinical Chemists (CSCC) Monoclonal Gammopathy Interest Group (MGIG), which is composed of CSCC members with an interest in protein electrophoresis, has formed a Monoclonal Gammopathy Working Group (MGWG) to take initial steps towards standardization of SPE, UPE and immunotyping. Candidate standardization recommendations were developed, discussed and voted upon by the MGWG. Candidate recommendations that achieved 90% agreement are presented as consensus recommendations. Recommendations that did not achieve 90% consensus remain candidate recommendations and are presented with accompanying MGWG discussion. Eleven consensus recommendations along with candidate recommendations for nomenclature, protein fraction reporting, test utilization, interference handling and interpretive reporting options are presented., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Serum protein electrophoresis (SPE) and immunofixation electrophoresis (IFE) are used in the diagnosis and monitoring of plasma cell dyscrasias. IFE is considered the most sensitive method for the detection of monoclonal proteins (M-proteins), but it is not quantitative. The goal of this study was to establish the analytical sensitivity and diagnostic performance of SPE on the Sebia Hydrasys using HYDRAGEL 30 PROTEIN(E) β1-β2., Methodology: Patient sera with a previously identified M-protein (IgG, IgA or IgM) were serially diluted with a normal serum pool and electrophoresed on the Sebia Hydrasys using HYDRAGEL 30 PROTEIN(E) β1-β2. The SPE gels were individually interpreted by five independent observers and IFE was performed on selected samples. Limit of detection was determined as the lowest concentration of M-protein band visible on the gel. SPE diagnostic performance was evaluated against the "gold standard" IFE according CLSI EP12-A2 guidelines., Results: Detection limit was comparable among all M-proteins migrating in the gamma region, IgG-κ (0.18±0.08g/L; n=6), IgG-λ (0.36±0.25g/L; n=8), IgA-κ (0.40±0.13g/L; n=7), IgA-λ (0.37±0.23g/L; n=4), IgM-κ (0.47±0.20g/L; n=13) and IgM-λ (0.29±0.24g/L; n=6). Percentage agreement with IFE for IgG and IgA in the gamma region ranged from 65% to 100%, whereas IgM migrating in the gamma region and immunoglobulins co-migrating with alpha or beta globulins, showed poor (0-38%) agreement., Conclusions: This study evaluates the analytical sensitivity and diagnostic performance of SPE on the Sebia Hydrasys using HYDRAGEL 30 PROTEIN(E) β1-β2. There was acceptable agreement between SPE and IFE for IgG-κ/λ and IgA-κ/λ migrating in the gamma region, suggesting that repeating IFE for samples with these isotypes, when the previous IFE and second SPE are both negative, may not be necessary., (Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Interactions between macrophages and adipocytes influence both metabolism and inflammation. Obesity-induced changes to macrophages and adipocytes lead to chronic inflammation and insulin resistance. This paper reviews the various functions of macrophages in lean and obese adipose tissue and how obesity alters adipose tissue macrophage phenotypes. Metabolic disease and insulin resistance shift the balance between numerous pro- and anti-inflammatory regulators of macrophages and create a feed-forward loop of increasing inflammatory macrophage activation and worsening adipocyte dysfunction. This ultimately leads to adipose tissue fibrosis and diabetes. The molecular mechanisms underlying these processes have therapeutic implications for obesity, metabolic syndrome, and diabetes., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: The CALIPER program has established a comprehensive database of age- and sex-stratified pediatric reference intervals for over 85 common biochemical markers, largely using the Abbott ARCHITECT assays. To allow a broader application of the CALIPER database, we examined transference to 36 Beckman Coulter Synchron Unicel DxC800 assays, based on the CLSI C28-A3/EP9-A3 guidelines., Methods: Patient sample comparisons were performed for 36 biochemical assays using 200 serum specimens obtained from pediatric patients on the Abbott ARCHITECT ci8200 and the Beckman Coulter DxC800. For each analyte, R(2) values were calculated to assess the quality of correlation between the platforms. Statistical criteria used to assess transferability included a) regression analysis to create the equation of the line of best fit, b) standardized residual, c) Bland-Altman, and d) quantile-quantile plots. Transferred reference intervals were further verified by analyzing serum samples from 100 healthy children from the CALIPER cohort on the Beckman Coulter system., Results: The reference intervals for most of the assessed analytes were transferable to Beckman Coulter assays (31 out of 36 studied) and the newly calculated reference intervals were verified through analysis of CALIPER reference samples (28 out of 31). Eighteen assays demonstrated excellent correlation (R(2)≥0.95), and 13 assays showed strong correlation (0.77≤R2≤0.94)., Conclusion: The current study allowed successful transference of a large number of biochemical markers from the CALIPER database to assays on the Beckman Coulter DxC800 platform. Transference should facilitate broader application of CALIPER reference intervals at pediatric centers using DxC biochemical assays., (Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Recently peptide-based inhibitors have been used to selectively inhibit a family of epigenetic enzymes called protein arginine N-methyltransferases (PRMTs), which has been implicated in different physiological processes and human diseases, such as heart disease and cancer. The diverse efforts to tease out subtle structural differences among PRMT enzymes in order to generate selective inhibitors as well as existing challenges in the field will be examined. The acquisition of PRMT substrate sequence preferences and structural information obtained from small-molecule inhibitors have helped in developing different peptide-based inhibitors that show great promise not only as inhibitors, but also as molecular probes to characterize PRMTs.

Protein arginine methylation is one of the epigenetic modifications to proteins that is studied in yeast and is known to be involved in a number of human diseases. All eukaryotes produce Nη-monomethylarginine (ηMMA), asymmetric Nη1, Nη1-dimethylarginine (aDMA), and most produce symmetric Nη1, Nη2-dimethylarginine (sDMA) on proteins, but only yeast produce Nδ-monomethylarginine (δMMA). It has proven difficult to differentiate among all of these methylarginines using mass spectrometry. Accordingly, we demonstrated that the two forms of MMA have indistinguishable primary product ion spectra. However, the secondary product ion spectra of δMMA and ηMMA exhibited distinct patterns of ions. Using incorporation of deuterated methyl-groups in yeast, we determined which secondary product ions were methylated and their structures. Utilizing distinct secondary product ions, a triple quadrupole multiple reaction monitoring cubed (MRM(3)) assay was developed to measure δMMA, ηMMA, sDMA and aDMA derived from hydrolyzed protein. As a proof-of-concept, δMMA and ηMMA were measured using the MRM(3) method in wild type and mutant strains of Saccharomyces cerevisiae and compared to the total MMA measured using an existing assay. The MRM(3) assay represents the only method to directly quantify δMMA and the only method to simultaneously quantify all yeast methylarginines., (Copyright © 2013 Elsevier B.V. All rights reserved.)