Publications by authors named "Christopher Lewis"

Aim: The aim of the present study was to define whether cardiac myosin contributes to energy conservation in the heart of hibernating mammals.

Methods: Thin cardiac strips were isolated from the left ventricles of active and hibernating grizzly bears; and subjected to loaded Mant-ATP chase assays, X-ray diffraction and proteomics.

Main Findings: Hibernating grizzly bears displayed an unusually high proportion of ATP-conserving super-relaxed cardiac myosin molecules that are likely due to altered levels of phosphorylation and rod region stability.

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This review of non-tuberculous mycobacterial pulmonary disease over an 11-year period identified 87 patients (74% women, mean age 66 years). Mycobacterium avium complex was isolated in 86% of patients. Antibiotics were commenced in 52% of patients; however, treatment was poorly tolerated with 36% terminating prematurely.

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  • - The study examined the impact of social media usage (Instagram and Twitter) by Physical Medicine & Rehabilitation residencies on the number of applications received during the 2020-2021 NRMP application cycle.
  • - Out of 88 programs, a significant portion (77%) had Instagram, 51% had Twitter, and many created accounts during the pandemic, which correlated with an increase in applications.
  • - Findings indicated that programs with active social media, particularly Twitter, and larger sizes had higher application numbers, suggesting a need for further research on how social media influences applicants' choices.
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The transition from acute to chronic low back pain (LBP) in community settings is not well understood. The purpose of this study was to assess the feasibility of recruitment and estimate the transition and continuation of chronic LBP. We also explored characteristics associated with this transition to chronic LBP.

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  • The study focuses on developing a standardized approach to project-based learning in Clinical Informatics (CI) fellowships, integrating principles from adult learning theory and improvement sciences.
  • This methodology aims to enhance fellows' skills in collaboration, project management, and leadership, enabling them to operate independently within 15 to 21 months.
  • The findings suggest that project-based learning not only supports fellows' learning objectives but also addresses organizational needs by leveraging their expertise in clinical workflows and technology.
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Introduction: Acute low back pain (LBP) is a common experience; however, the associated pain severity, pain frequency, and characteristics of individuals with acute LBP in community settings have yet to be well understood. In this manuscript, two acute-LBP severity categorization definitions were developed: 1) pain impact frequency (impact-based) and 2) pain intensity (intensity-based) severity categories. The purpose of this manuscript is to describe and then compare these acute-LBP severity groups in the following characteristics: 1) sociodemographic, 2) general and physical health, and 3) psychological using a feasibility cohort study.

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Acute mountain sickness (AMS) is a well-studied illness defined by clinical features (e.g., headache and nausea), as assessed by the Lake Louise score (LLS).

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With an increasing prevalence of sedentary lifestyles driving a prominent public health crisis, digital health tools such as wearable technologies are revolutionizing clinicians' ability to track physical activity and exercise. Despite their ubiquity in the consumer market, these technologies have not yet been fully incorporated into clinical practice. Though these tools promise efficacy and accessibility, a careful review of the current literature is important to understand the challenges and future promise of clinical implementation.

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Patients receiving mechanical ventilation in the intensive care unit (ICU) frequently develop contractile weakness of the diaphragm. Consequently, they may experience difficulty weaning from mechanical ventilation, which increases mortality and poses a high economic burden. Because of a lack of knowledge regarding the molecular changes in the diaphragm, no treatment is currently available to improve diaphragm contractility.

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Background: A goal of gender-affirming hormone therapy (GAHT) for transgender women is to use estradiol to suppress endogenous production of testosterone. However, the effects of different estradiol regimens and route of administration on testosterone suppression is unknown. This is the first open-label randomized trial comparing different GAHT regimens for optimal estradiol route and dosing.

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  • - A 66-year-old female developed a lump under her skin, which turned out to be a sterilisation clip that migrated from a procedure she had 24 years prior.
  • - The patient was referred to the Surgical Emergency Unit after noticing pain and tenderness around the lump, which was confirmed via ultrasound to be a foreign body.
  • - This case highlights the rare occurrence of sterilisation clip migration, suggesting that healthcare providers should be alert to the possibility, especially in patients with prior sterilisation and no recent trauma.
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We introduce Ultra-Flexible Tentacle Electrodes (UFTEs), packing many independent fibers with the smallest possible footprint without limitation in recording depth using a combination of mechanical and chemical tethering for insertion. We demonstrate a scheme to implant UFTEs simultaneously into many brain areas at arbitrary locations without angle-of-insertion limitations, and a 512-channel wireless logger. Immunostaining reveals no detectable chronic tissue damage even after several months.

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Hibernation is a period of metabolic suppression utilized by many small and large mammal species to survive during winter periods. As the underlying cellular and molecular mechanisms remain incompletely understood, our study aimed to determine whether skeletal muscle myosin and its metabolic efficiency undergo alterations during hibernation to optimize energy utilization. We isolated muscle fibers from small hibernators, and and larger hibernators, and .

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Background: Survivors of hospitalization for severe acute COVID-19 infection faced significant functional impairments necessitating discharge to inpatient rehabilitation facilities (IRFs) for intensive rehabilitation prior to discharge home. There remains a lack of large cohort studies of the functional outcomes of patients admitted to IRFs with COVID-19-related impairments and the relationship to patient-specific factors.

Objective: To characterize functional outcomes of patients admitted to IRFs for COVID-19-related debility and to investigate associations between functional outcomes and patient-specific factors.

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This updated British Society for Haematology guideline provides an up-to-date literature review and recommendations regarding the identification and management of preoperative anaemia. This includes guidance on thresholds for the diagnosis of anaemia and the diagnosis and management of iron deficiency in the preoperative context. Guidance on the appropriate use of erythropoiesis-stimulating agents and preoperative transfusion is also provided.

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Neurons in primary visual cortex integrate sensory input with signals reflecting the animal's internal state to support flexible behavior. Internal variables, such as expectation, attention, or current goals, are imposed in a top-down manner via extensive feedback projections from higher-order areas. We optogenetically activated a high-order visual area, area 21a, in the lightly anesthetized cat (OptoTD), while recording from neuronal populations in V1.

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An essential feature of neurons is their ability to centrally integrate information from their dendrites. The activity of astrocytes, in contrast, has been described as mostly uncoordinated across cellular compartments without clear central integration. Here we report conditional integration of calcium signals in astrocytic distal processes at their soma.

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Background: Neighborhoods with more social determinants of health (SDOH) risk factors have higher rates of infectivity, morbidity, and mortality from COVID-19. Patients with severe COVID-19 infection can have long-term functional deficits leading to lower quality of life (QoL) and independence measures. Research shows that these patients benefit greatly from inpatient rehabilitation facilities (IRF) admission, but there remains a lack of studies investigating long-term benefits of rehabilitation once patients are returned to their home environment.

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Extracellular recordings with planar microelectrodes are the gold standard technique for recording the fast action potentials of neurons in the intact brain. The introduction of microfabrication techniques has revolutionized the in vivo recording of neuronal activity and introduced high-density, multi-electrode arrays that increase the spatial resolution of recordings and the number of neurons that can be simultaneously recorded. Despite these innovations, there is still debate about the ideal electrical transfer characteristics of extracellular electrodes.

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Background: Current guidelines for gender-affirming hormone therapy (GAHT) for transgender women are mostly based on clinical experience from experts in the field and treatments used on postmenopausal women. While care is currently provided with the best available evidence, there is a critical gap in knowledge about the safest and most effective estradiol routes of administration for GAHT in transgender women; this statement is supported by the World Professional Association for Transgender Health on their Standards of Care for the Health of Transgender and Gender Diverse People, version 8. Furthermore, the reported rates of cardiometabolic adverse events in transgender women highlight the importance of investigating changes in lipoproteins, glucose, and insulin sensitivity, among other markers while receiving GAHT.

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Hibernation is a period of metabolic suppression utilized by many small and large mammal species to survive during winter periods. As the underlying cellular and molecular mechanisms remain incompletely understood, our study aimed to determine whether skeletal muscle myosin and its metabolic efficiency undergo alterations during hibernation to optimize energy utilization. We isolated muscle fibers from small hibernators, Ictidomys tridecemlineatus and Eliomys quercinus and larger hibernators, Ursus arctos and Ursus americanus.

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Neurons in the medial prefrontal cortex (mPFC) are functionally linked to working memory (WM) but how distinct projection pathways contribute to WM remains unclear. Based on optical recordings, optogenetic perturbations, and pharmacological interventions in male mice, we report here that dorsomedial striatum (dmStr)-projecting mPFC neurons are essential for WM maintenance, but not encoding or retrieval, in a T-maze spatial memory task. Fiber photometry of GCaMP6m-labeled mPFC→dmStr neurons revealed strongest activity during the maintenance period, and optogenetic inhibition of these neurons impaired performance only when applied during this period.

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Acute low back pain (LBP) is a common experience, however, the associated pain severity, pain frequency, and characteristics of individuals with acute LBP in community settings have yet to be well understood. In this manuscript, three acute LBP severity categorization definitions were used based on LBP frequency combined with either 1) pain impact frequency (impact-based) or 2) pain intensity (intensity-based), as well as LBP pain interference frequency (interference only-based) severity categories. The purpose of this manuscript is to describe and then compare these acute LBP severity groups in the following characteristics: 1) sociodemographic, 2) general and physical health, and 3) psychological.

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Transgender youth experience elevated rates of eating disorders, yet few screening measures have been validated with transgender patients. The purpose of this study was to provide initial evidence for the internal consistency and convergent validity of the Sick, Control, One Stone, Fat, Food (SCOFF) in a sample of transgender youth. Two hundred eight participants completed the SCOFF as part of a routine screening protocol.

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