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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.
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Testicular neoplasms, or testicular cancer, are not typically seen in the emergency department (ED) since their presentation involves a painless hard mass that emerges slowly over time. Uncommon presentation of testicular neoplasm to the ED with acute onset of scrotal pain may present challenges as an incomplete physical examination without supplemental imaging and laboratory workup may overlook the diagnosis of testicular neoplasm. As a result, a delay in proper treatment may occur. Early recognition of testicular neoplasm can decrease morbidity and mortality and improve overall patient survival. Here, we present a case of a 32-year-old male who presented in the ED with an acute onset of testicular pain localized on the posterior right side of the scrotum. Despite the unusual presentation, a complete physical examination, including a complete genitourinary system exam, was performed. During the physical examination, a high index of suspicion for testicular neoplasm was present. Necessary imaging and laboratory workup were ordered. Based on the findings, testicular neoplasm was highly suspected. Thus, surgical intervention was pursued to remove the suspicious mass and pathology revealed a mixed germ cell tumor. Further imaging and laboratory workup showed metastasis into other organ systems, and medical management was chosen to treat the metastatic neoplasm systemically.
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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.
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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.
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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.
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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.
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Complexo Citocromos b6f , Elétrons , Complexo Citocromos b6f/metabolismo , Transporte de Elétrons , Fotossíntese/fisiologia , Oxirredução , Oxidantes , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , LuzRESUMO
Illicit drug use during pregnancy is a concern worldwide, with many international studies describing attempted strategies to mitigate this problem. Drug misuse during pregnancy is associated with significant maternal as well as perinatal complications, which include a high incidence of stillbirths, fetal distress, neonatal abstinence syndrome (NAS) and increased neonatal mortality. Unfortunately, the identification of a drug-exposed mother or neonate is challenging. Maternal disclosure of drug use is often inaccurate, principally due to psychosocial factors including behavioral denial or the fear of the consequences resulting from such admissions. Likewise, many infants who have been exposed to drugs in utero may appear normal at birth and initially show no overt manifestations of drug effects. Thus, the identification of the drug-exposed infant requires a high index of clinical suspicion. Conversely, analytical testing is an objective means of determining drug exposure when it may be necessary to document proof of the infant's exposure to illicit drugs. The review will discuss the different matrices that are most commonly used for testing (e.g., maternal urine, neonatal urine, meconium, and umbilical cord), the strengths and limitations for each matrix, which drugs and metabolites are appropriate for testing, the various testing methods, and the advantages and disadvantages of each method.
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Drogas Ilícitas , Síndrome de Abstinência Neonatal , Complicações na Gravidez , Transtornos Relacionados ao Uso de Substâncias , Gravidez , Recém-Nascido , Feminino , Humanos , Síndrome de Abstinência Neonatal/diagnóstico , Síndrome de Abstinência Neonatal/complicações , Síndrome de Abstinência Neonatal/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Mecônio/metabolismo , Hospitalização , Complicações na Gravidez/diagnósticoRESUMO
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 95th 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.
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Escorregamento das Epífises Proximais do Fêmur , Humanos , Escorregamento das Epífises Proximais do Fêmur/diagnóstico , Escorregamento das Epífises Proximais do Fêmur/epidemiologia , Escorregamento das Epífises Proximais do Fêmur/etiologia , Trinidad e Tobago/epidemiologia , Incidência , Fêmur , Fatores de RiscoRESUMO
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.
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Fibrose Cística , Células-Tronco Pluripotentes Induzidas , Animais , Fibrose Cística/tratamento farmacológico , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Células Epiteliais/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Transporte de ÍonsRESUMO
The synthesis of arylamines from renewable resources under mild reaction conditions is highly desired for the sustainability of the chemical industry, where the production of hazardous waste is a prime concern. However, to date, there are very few tools in chemists' toolboxes that are able to produce arylamines in a sustainable manner. Herein, a robust one-pot approach for constructing bio-based arylamines via a combined photooxidative dearomatization-rearomatization strategy is presented. The developed methodology enables the synthesis of structurally complex amines in moderate-to-good isolated yields using biomass-derived phenols, natural α-amino acids, and naphthols under remarkably mild reaction conditions. For the photooxygenation of phenols, a novel chrysazine-based catalyst system was introduced, demonstrating its efficiency for the synthesis of natural products - hallerone, rengyolone, and the pharmaceutically relevant prodrug DHED.
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Aminas , Naftóis , Aminas/química , Catálise , Naftóis/química , FenóisRESUMO
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.
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Tree sloths rely on their limb flexors for bodyweight support and joint stability during suspensory locomotion and posture. This study aims to describe the myology of three-toed sloths and identify limb muscle traits that indicate modification for suspensorial habit. The pelvic limbs of the brown-throated three-toed sloth (Bradypus variegatus) were dissected, muscle belly mass was recorded, and the structural arrangements of the muscles were documented and compared with the available myological accounts for sloths. Overall, the limb musculature is simplified by containing muscles with generally long and parallel fascicles. A number of specific and informative muscle traits are additionally observed in the pelvic limb of B. variegatus: well-developed hip flexors and hip extensors each displaying several fused bellies; massive knee flexors; two heads of the m. adductor longus and m. gracilis; robust digital flexors and flexor tendons; m. tibialis cranialis muscle complex originating from the tibia and fibula and containing a modified m. extensor digitorum I longus; appreciable muscle mass devoted to ankle flexion and hindfoot supination; only m. extensor digitorum brevis acts to extend the digits. Collectively, the findings for tree sloths emphasize muscle mass and organization for suspensory support namely by the hip flexors, knee flexors, and limb adductors, for which the latter two groups may stabilize suspensory postures by exerting appreciable medially-directed force on the substrate. Specializations in the distal limb are also apparent for sustained purchase of the substrate by forceful digital flexion coupled with strong ankle flexion and supination of the hind feet, which is permitted by the reorganization of several digital extensors. Moreover, the reduction or loss of other digital flexor and ab-adductor muscles marks a dramatic simplification of the intrinsic foot musculature in B. variegatus, the extent to which varies across extant species of two- and three-toed tree sloths and likely is related to substrate preference/use.
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Bichos-Preguiça , Animais , Membro Posterior/fisiologia , Locomoção/fisiologia , Músculo Esquelético , Postura , Bichos-Preguiça/fisiologiaAssuntos
Clavícula/lesões , Fraturas Ósseas/etiologia , Hiperparatireoidismo Primário/etiologia , Glândulas Paratireoides/cirurgia , Hormônio Paratireóideo/sangue , Neoplasias das Paratireoides/diagnóstico , Adulto , Coristoma/cirurgia , Fraturas Ósseas/diagnóstico por imagem , Humanos , Hipercalcemia/etiologia , Hiperparatireoidismo Primário/terapia , Hipocalcemia/tratamento farmacológico , Hipocalcemia/etiologia , Masculino , Glândulas Paratireoides/diagnóstico por imagem , Neoplasias das Paratireoides/sangue , Neoplasias das Paratireoides/complicações , Neoplasias das Paratireoides/cirurgia , Tomografia por Emissão de Pósitrons , Ombro/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada por Raios XRESUMO
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.
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Custos de Cuidados de Saúde , Acessibilidade aos Serviços de Saúde , Qualidade da Assistência à Saúde , Consulta Remota , Humanos , Atenção Primária à Saúde , Consulta Remota/economia , Consulta Remota/estatística & dados numéricos , Telemedicina , Resultado do TratamentoRESUMO
OBJECTIVE: Medium chain triglycerides (MCT) have unique metabolic properties which may improve insulin sensitivity (Si) and beta cell function but data in humans are limited. We conducted a 6-week clinical trial of MCT oil supplementation. METHODS: 22 subjects without diabetes (8 males, 14 females, mean ± standard error age 39±2.9 years, baseline BMI 27.0±1.4 kg/m2) were counseled to maintain their body weight and physical activity (PA) during the trial. Dietary intake, PA data, body composition, and resting energy expenditure (REE) were obtained through dietary recall, international PA questionnaire, dual x-ray absorptiometry, and indirect calorimetry, respectively. MCT prescriptions were given based on REE and PA to replace part of dietary fat with 30 grams of MCT per 2000 kcal daily. Insulin-modified frequently sampled intravenous glucose tolerance tests were performed before and after MCT to measure changes in Si, acute insulin response (AIR), disposition index (DI), and glucose effectiveness (Sg). RESULTS: MCT were well tolerated and weight remained stable (mean change 0.3 kg, p = 0.39). Fasting REE, respiratory quotient, and body composition were stable during the intervention. There were no significant changes in mean fasting glucose, insulin, insulin resistance, fasting total ketones, Si, AIR, DI, Sg, leptin, fructosamine, and proinsulin. The mean change in Si was 0.5 10-4 min-1 per mU/L (95% CI: -1.4, 2.4), corresponding to a 12% increase from baseline, and the range was -4.7 to 12.9 10-4 min-1 per mU/L. Mean total adiponectin decreased significantly from 22925 ng/mL at baseline to 17598 ng/mL at final visit (p = 0.02). The baseline clinical and laboratory parameters were not significantly associated with the change in Si. DISCUSSION: There were a wide range of changes in the minimal model parameters of glucose and insulin metabolism in subjects following 6 weeks of MCT as an isocaloric substitution for part of usual dietary fat intake. Since this was a single-arm non-randomized study without a control group, it cannot be certain whether these changes were due to MCT so further randomized controlled trials are warranted.
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Gorduras na Dieta/administração & dosagem , Suplementos Nutricionais , Resistência à Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Obesidade/dietoterapia , Triglicerídeos/administração & dosagem , Adipocinas/sangue , Adulto , Composição Corporal/efeitos dos fármacos , Estudos de Viabilidade , Feminino , Teste de Tolerância a Glucose , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/fisiologia , Masculino , Obesidade/metabolismo , Obesidade/fisiopatologia , Projetos PilotoRESUMO
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.
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Células Epiteliais Alveolares/citologia , Técnicas de Cultura de Células/métodos , Células-Tronco Pluripotentes/citologia , Células Epiteliais Alveolares/fisiologia , Animais , Diferenciação Celular , Linhagem Celular , Linhagem da Célula , Proliferação de Células , Autorrenovação Celular/genética , Autorrenovação Celular/fisiologia , Células Epiteliais/citologia , Células Alimentadoras , Humanos , Pulmão/citologia , Células-Tronco Pluripotentes/fisiologiaRESUMO
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.
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Biomarcadores/sangue , Laboratórios/normas , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito/estatística & dados numéricos , Troponina I/sangue , Troponina T/sangue , Bioensaio , Feminino , Humanos , Masculino , Triagem/estatística & dados numéricosRESUMO
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.
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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 O2 to H2O through flavodiiron proteins (FLVs) and (ii) plastid terminal oxidases (PTOX) and (iii) the synthesis of starch. Real-time measurements of O2 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 O2 reduction. However, when starch synthesis is compromised, a greater proportion of the electrons is directed toward O2 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 (H2O; 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.
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Transporte de Elétrons/fisiologia , Fotossíntese/fisiologia , Chlamydomonas reinhardtii/metabolismo , Chlamydomonas reinhardtii/fisiologia , Escuridão , Luz , Oxirredutases/metabolismo , Oxigênio/metabolismo , Proteínas de Plantas/metabolismo , Plastídeos/metabolismo , Plastídeos/fisiologiaRESUMO
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.