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While studying the aortic valve in isolation has facilitated the development of life-saving procedures and technologies, the dynamic interplay of the aortic valve and its surrounding structures is vital to preserving their function across the wide range of conditions encountered in an active lifestyle. Our view is that these structures should be viewed as an integrated functional unit, herein referred to as the aortic valve apparatus (AVA). The coupling of the aortic valve and root, left ventricular outflow tract, and blood circulation is crucial for AVA's functions: unidirectional flow out of the left ventricle, coronary perfusion, reservoir function, and supporting left ventricular function. In this review, we explore the multiscale biological and physical phenomena that underly the simultaneous fulfilment of these functions. A brief overview of the tools used to investigate the AVA is included, such as: medical imaging modalities, experimental methods, and computational modelling, specifically fluid-structure interaction (FSI) simulations, is included. Some pathologies affecting the AVA are explored, and insights are provided on treatments and interventions that aim to maintain quality of life. The concepts explained in this paper support the idea of AVA being an integrated functional unit and help identify unanswered research questions. Incorporating phenomena through the molecular, micro, meso and whole tissue scales is crucial for understanding the sophisticated normal functions and diseases of the AVA.
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Field emission of electrons underlies great advances in science and technology, ranging from signal processing at ever higher frequencies1 to imaging of the atomic-scale structure of matter2 with picometre resolution. The advancing of electron microscopy techniques to enable the complete visualization of matter on the native spatial (picometre) and temporal (attosecond) scales of electron dynamics calls for techniques that can confine and examine the field emission on sub-femtosecond time intervals. Intense laser pulses have paved the way to this end3,4 by demonstrating femtosecond confinement5,6 and sub-optical cycle control7,8 of the optical field emission9 from nanostructured metals. Yet the measurement of attosecond electron pulses has remained elusive. We used intense, sub-cycle light transients to induce optical field emission of electron pulses from tungsten nanotips and a weak replica of the same transient to directly investigate the emission dynamics in real time. Access to the temporal properties of the electron pulses rescattering off the tip surface, including the duration τ = (53 as ± 5 as) and chirp, and the direct exploration of nanoscale near fields open new prospects for research and applications at the interface of attosecond physics and nano-optics.
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Valence electrons contribute a small fraction of the total electron density of materials, but they determine their essential chemical, electronic and optical properties. Strong laser fields can probe electrons in valence orbitals1-3 and their dynamics4-6 in the gas phase. Previous laser studies of solids have associated high-harmonic emission7-12 with the spatial arrangement of atoms in the crystal lattice13,14 and have used terahertz fields to probe interatomic potential forces15. Yet the direct, picometre-scale imaging of valence electrons in solids has remained challenging. Here we show that intense optical fields interacting with crystalline solids could enable the imaging of valence electrons at the picometre scale. An intense laser field with a strength that is comparable to the fields keeping the valence electrons bound in crystals can induce quasi-free electron motion. The harmonics of the laser field emerging from the nonlinear scattering of the valence electrons by the crystal potential contain the critical information that enables picometre-scale, real-space mapping of the valence electron structure. We used high harmonics to reconstruct images of the valence potential and electron density in crystalline magnesium fluoride and calcium fluoride with a spatial resolution of about 26 picometres. Picometre-scale imaging of valence electrons could enable direct probing of the chemical, electronic, optical and topological properties of materials.
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BACKGROUND: Nontoxigenic Corynebacterium diphtheriae, often associated with wounds, can rarely cause infective endocarditis (IE). Five patients with C. diphtheriae IE were identified within 12 months at a Seattle-based hospital system. We reviewed prior C. diphtheriae-positive cultures to determine if detections had increased over time and evaluated epidemiologic trends. METHODS: We conducted a formal electronic health record search to identify all patients aged ≥18 years with C. diphtheriae detected in a clinical specimen (ie, wound, blood, sputum) between 1 September 2020 and 1 April 2023. We collected patient demographics, housing status, comorbidities, substance-use history, and level of medical care required at detection. We extracted laboratory data on susceptibilities of C. diphtheriae isolates and on other pathogens detected at the time of C. diphtheriae identification. RESULTS: Between 1 September 2020 and 1 April 2023, 44 patients (median age, 44 years) had a C. diphtheriae-positive clinical culture, with most detections occurring after March 2022. Patients were predominantly male (75%), White (66%), unstably housed (77%), and had a lifetime history of injecting drugs (75%). Most C. diphtheriae-positive cultures were polymicrobial, including wound cultures from 36 (82%) patients and blood cultures from 6 (14%) patients, not mutually exclusive. Thirty-four patients (77%), including all 5 patients with C. diphtheriae IE, required hospital admission for C. diphtheriae or a related condition. Of the 5 patients with IE, 3 died of IE and 1 from COVID-19. CONCLUSIONS: Findings suggest a high-morbidity outbreak disproportionately affecting patients who use substances and are unstably housed.
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Corynebacterium diphtheriae , Difteria , Humanos , Masculino , Adulto , Feminino , Washington/epidemiologia , Pessoa de Meia-Idade , Corynebacterium diphtheriae/isolamento & purificação , Difteria/epidemiologia , Difteria/microbiologia , Endocardite Bacteriana/epidemiologia , Endocardite Bacteriana/microbiologia , Adulto Jovem , Idoso , Antibacterianos/uso terapêutico , Endocardite/microbiologia , Endocardite/epidemiologiaRESUMO
Hermona Soreq holds a Hebrew University Slesinger Chair in Molecular Neuroscience and is among the founding members of the Edmond and Lily Safra Center of Brain Sciences (ELSC). Soreq's research (H-impact: 98) focuses on acetylcholine (ACh)-related pathways and combines RNA-sequencing technologies, transgenic engineering, and molecular biology tests with in-depth analysis approaches. Her work addresses microRNAs (miRs) and transfer RNA fragments (tRFs) which have rapidly acquired wide recognition as global controllers of regulatory processes in healthy and diseased brain and body, including anxiety, inflammation, and cognition. Altogether, Soreq's work leads to molecular neuroscience-driven prevention and/or intervention with diseases involving impaired ACh signaling, including schizophrenia, bipolar disorder, Alzheimer's disease, and stress. Hermona led this Special Issue based on the 17th Symposium on Cholinergic Mechanisms (ISCM2022). We interviewed her on the progress in the field, what she wants to achieve as Senior Editor for the Gene Regulation and Genetics category at the Journal of Neurochemistry, key moments, and future directions.
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Doença de Alzheimer , MicroRNAs , Humanos , Feminino , Encéfalo , Transdução de Sinais , ColinérgicosRESUMO
BACKGROUND: Hormone receptor expression is a known positive prognostic and predictive factor in breast cancer; however, limited evidence exists on its prognostic impact on prognosis of young patients harboring a pathogenic variant (PV) in the BRCA1 and/or BRCA2 genes. PATIENTS AND METHODS: This international, multicenter, retrospective cohort study included young patients (aged ≤40 years) diagnosed with invasive breast cancer and harboring germline PVs in BRCA genes. We investigated the impact of hormone receptor status on clinical behavior and outcomes of breast cancer. Outcomes of interest [disease-free survival (DFS), breast cancer-specific survival (BCSS), and overall survival (OS)] were first investigated according to hormone receptor expression (positive versus negative), and then according to breast cancer subtype [luminal A-like versus luminal B-like versus triple-negative versus human epidermal growth factor receptor 2 (HER2)-positive breast cancer]. RESULTS: From 78 centers worldwide, 4709 BRCA carriers were included, of whom 2143 (45.5%) had hormone receptor-positive and 2566 (54.5%) hormone receptor-negative breast cancer. Median follow-up was 7.9 years. The rate of distant recurrences was higher in patients with hormone receptor-positive disease (13.1% versus 9.6%, P < 0.001), while the rate of second primary breast cancer was lower (9.1% versus 14.7%, P < 0.001) compared to patients with hormone receptor-negative disease. The 8-year DFS was 65.8% and 63.4% in patients with hormone receptor-positive and negative disease, respectively. The hazard ratio of hormone receptor-positive versus negative disease changed over time for DFS, BCSS, and OS (P < 0.05 for interaction of hormone receptor status and survival time). Patients with luminal A-like breast cancer had the worst long-term prognosis in terms of DFS compared to all the other subgroups (8-year DFS: 60.8% in luminal A-like versus 63.5% in triple-negative versus 65.5% in HER2-positive and 69.7% in luminal B-like subtype). CONCLUSIONS: In young BRCA carriers, differences in recurrence pattern and second primary breast cancer among hormone receptor-positive versus negative disease warrant consideration in counseling patients on treatment, follow-up, and risk-reducing surgery.
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Carbohydrates have various biological functions that are based on their structures. However, the composition and the glycosidic-bond linkage and configuration of carbohydrates present challenges for their characterization. Furthermore, isomeric features contribute to the formation of intramolecular hydrogen bonds, which influence the flexibility and dynamics of carbohydrates. Hydrogen/deuterium exchange-mass spectrometry (HDX-MS) enables the analysis of protein dynamics by monitoring deuterium labeling after HDX for different lengths of time. In-electrospray ionization (in-ESI) HDX-MS has been used to rapidly label solvated carbohydrates with labeling occurring during desolvation of ESI droplets. Therefore, HDX-labeling times can be altered by changing the spray-solvent conductivity, which changes the initial size of ESI droplets and their resulting lifetimes. Here, we utilize in-ESI HDX-MS to characterize nine isomeric disaccharides with different monosaccharide compositions and glycosidic-bond linkages and configurations. We compared both the relative D-uptake of isomers at individual conductivities, or HDX-labeling times, and the trends associated with labeling at multiple conductivities. Interestingly, the relative D-uptake trends were correlated to isomeric features that affect disaccharide flexibility, including formation of intramolecular hydrogen bonds. Among the isomeric features studied, linkage was observed to have a significant influence on relative D-uptake with (1-3)-linked disaccharides having more change in relative D-uptake with changing conductivity compared to other linkages. Overall, this research illustrates how in-ESI HDX-MS can be applied to structurally characterize disaccharides with distinct isomeric features. Furthermore, this work shows that in-ESI HDX-MS can be used to monitor the dynamics of solvated molecules with rapidly exchanging functional groups.
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Dissacarídeos , Espectrometria de Massa com Troca Hidrogênio-Deutério , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização por Electrospray/métodos , Dissacarídeos/química , Solventes/química , Ligação de Hidrogênio , IsomerismoRESUMO
Pump-probe nano-optical experiments were used to study the light-induced insulator to metal transition (IMT) in thin films of vanadium dioxide (VO_{2}), a prototypical correlated electron system. We show that inhomogeneous optical contrast is prompted by spatially uniform photoexcitation, indicating an inhomogeneous photosusceptibility of VO_{2}. We locally characterize temperature and time dependent variations of the photoexcitation threshold necessary to induce the IMT on picosecond timescales with hundred nanometer spatial resolution. We separately measure the critical temperature T_{L}, where the IMT onsets and the local transient electronic nano-optical contrast at the nanoscale. Our data reveal variations in the photosusceptibility of VO_{2} within nanoscopic regions characterized by the same critical temperature T_{L} where metallic domains can first nucleate.
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We report an estimation of the injected mass composition of ultrahigh energy cosmic rays (UHECRs) at energies higher than 10 EeV. The composition is inferred from an energy-dependent sky distribution of UHECR events observed by the Telescope Array surface detector by comparing it to the Large Scale Structure of the local Universe. In the case of negligible extragalactic magnetic fields (EGMFs), the results are consistent with a relatively heavy injected composition at Eâ¼10 EeV that becomes lighter up to Eâ¼100 EeV, while the composition at E>100 EeV is very heavy. The latter is true even in the presence of highest experimentally allowed extragalactic magnetic fields, while the composition at lower energies can be light if a strong EGMF is present. The effect of the uncertainty in the galactic magnetic field on these results is subdominant.
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AIM: To verify the diagnostic performance of the loss of nigrosome-1 on susceptibility-weighted imaging (SWI) with compressed sensing-sensitivity encoding (CS-SENSE) and neuromelanin on neuromelanin-sensitive (NM) magnetic resonance imaging (MRI) for the diagnosis of Parkinson's disease (PD) and atypical Parkinsonism. MATERIALS AND METHODS: A total of 195 patients who underwent MRI between October 2019 and February 2020, including SWI, with or without CS-SENSE, and NM-MRI, were reviewed retrospectively. Two neuroradiologists assessed the loss of nigrosome-1 on SWI and neuromelanin on the NM-MRI. The result of N-3-fluoropropyl-2-beta-carbomethoxy-3-beta-(4-iodophenyl) nortropane positron-emission tomography (PET) was set as the reference standard. RESULTS: When CS-SENSE was applied for nigrosome-1 imaging on SWI, the non-diagnostic scan rate was lowered significantly from 19.3% (17/88) to 5.6% (6/107; p=0.004). Diagnosis of PD and atypical Parkinsonism based on the loss of nigrosome-1 on SWI and based on NM-MRI showed good diagnostic value (area under the curve [AUC] 0.821, 95% confidence interval [CI] = 0.755-0.875: AUC 0.832, 95% CI = 0.771-0.882, respectively) with a substantial inter-reader agreement (κ = 0.791 and 0.681, respectively). Combined SWI and neuromelanin had a similar discriminatory ability (AUC 0.830, 95% CI = 0.770-0.880). Similarly, the diagnosis of PD was excellent. CONCLUSIONS: CS-SENSE may add value to the diagnostic capability of nigrosome-1 on SWI to reduce the nondiagnostic scan rates. Furthermore, loss of nigrosome-1 on SWI or volume loss of neuromelanin on NM-MRI may be helpful for diagnosing PD.
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Doença de Parkinson , Transtornos Parkinsonianos , Humanos , Doença de Parkinson/diagnóstico por imagem , Estudos Retrospectivos , Transtornos Parkinsonianos/diagnóstico , Imageamento por Ressonância Magnética/métodosRESUMO
AIM: The aim of this study was to identify preoperative magnetic resonance imaging (MRI) findings that can predict the shunt responsiveness in idiopathic normal-pressure hydrocephalus (iNPH) patients and to investigate postoperative outcome and complications. MATERIALS AND METHODS: A total of 192 patients with iNPH who underwent shunt at our hospital between 2000 and 2021 were included to investigate complications. Of these, after exclusion, 127 (1-month postoperative follow-up) and 77 (1-year postoperative follow-up) patients were evaluated. The preoperative MRI features (the presence of tightness of the high-convexity subarachnoid space, Sylvian fissure enlargement, Evans' index, and callosal angle) of the shunt-response and nonresponse groups were compared, and a systematic review was conducted to evaluate whether preoperative MRI findings could predict shunt response. RESULTS: Postoperative complications within one month after surgery were observed in 6.8% (13/192), and the most common complication was hemorrhage. Changes in corpus callosum were observed in 4.2% (8/192). The shunt-response rates were 83.5% (106/127) in the 1-month follow-up group and 70.1% (54/77) in 1-year follow-up group. In the logistic regression analysis, only Evans' index measuring >0.4 had a significant negative relationship with shunt response at 1-month follow-up; however, no significant relationship was observed at 1-year follow-up. According to our systematic review, it is still controversial whether preoperative MRI findings could predict shunt response. CONCLUSION: Evans' index measure of >0.4 had a significant relationship with the shunt response in the 1-month follow-up group. In systematic reviews, there is ongoing debate about whether preoperative MRI findings can accurately predict responses to shunt surgery. Postoperative corpus callosal change was observed in 4.2% of iNPH patients.
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Hidrocefalia de Pressão Normal , Imageamento por Ressonância Magnética , Complicações Pós-Operatórias , Humanos , Hidrocefalia de Pressão Normal/cirurgia , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Feminino , Masculino , Imageamento por Ressonância Magnética/métodos , Idoso , Complicações Pós-Operatórias/diagnóstico por imagem , Resultado do Tratamento , Derivações do Líquido Cefalorraquidiano , Estudos Retrospectivos , Cuidados Pré-Operatórios/métodos , Idoso de 80 Anos ou mais , Pessoa de Meia-IdadeRESUMO
Hyperangulated videolaryngoscopes are known to increase the success rate of tracheal intubation in the setting of difficult airway management when used with a stylet or bougie. However, there is controversy over which adjunct is more useful. This randomised study aimed to compare first attempt tracheal intubation success rate between a stylet and bougie when using a hyperangulated videolaryngoscope. We recruited patients aged > 20 years who were scheduled for elective surgery under general anaesthesia and required tracheal intubation. We only included patients with factors predicting difficult tracheal intubation based on pre-anaesthesia airway evaluation. Tracheal intubation was attempted using a Glidescope® with either a stylet or bougie as an adjunct according to group assignment. Primary outcome was the success rate of the first tracheal intubation attempt, and secondary outcomes were success of second and third attempts; tracheal intubation time; and occurrence of sore throat, dysphagia or hoarseness. A total of 166 patients were included. The success rate of the first tracheal intubation attempt was significantly higher in patients allocated to the bougie group compared with those allocated to the stylet group (81/83 (98%) vs. 73/83 (88%), respectively; p = 0.032). The number of patients who needed two attempts was significantly lower in those allocated to the bougie group compared with those allocated to the stylet group (1/83 (1%) vs. 9/83 (11%), respectively; p = 0.018). Each group had one patient (1%) where tracheal intubation was achieved after a third attempt. There was no significant difference in the occurrence of sore throat, dysphagia and hoarseness between the two groups. When difficult tracheal intubation is anticipated and a hyperangulated videolaryngoscope is used, the success rate of the first attempt is higher when a bougie is used compared with a stylet.
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Intubação Intratraqueal , Laringoscópios , Laringoscopia , Humanos , Intubação Intratraqueal/instrumentação , Intubação Intratraqueal/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Laringoscopia/métodos , Laringoscopia/instrumentação , Gravação em Vídeo , Adulto , Faringite/etiologia , Faringite/epidemiologia , Desenho de Equipamento , Anestesia Geral/métodos , Resultado do Tratamento , Rouquidão/etiologiaRESUMO
BACKGROUND: We conducted a preliminary phase I, dose-escalating, safety, and tolerability trial in the population of patients with acute intracerebral hemorrhage (ICH) by using human allogeneic bone marrow-derived mesenchymal stem/stromal cells. METHODS: Eligibility criteria included nontraumatic supratentorial hematoma less than 60 mL and Glasgow Coma Scale score greater than 5. All patients were monitored in the neurosciences intensive care unit for safety and tolerability of mesenchymal stem/stromal cell infusion and adverse events. We also explored the use of cytokines as biomarkers to assess responsiveness to the cell therapy. We screened 140 patients, enrolling 9 who met eligibility criteria into three dose groups: 0.5 million cells/kg, 1 million cells/kg, and 2 million cells/kg. RESULTS: Intravenous administration of allogeneic bone marrow-derived mesenchymal stem/stromal cells to treat patients with acute ICH is feasible and safe. CONCLUSIONS: Future larger randomized, placebo-controlled ICH studies are necessary to validate this study and establish the effectiveness of this therapeutic approach in the treatment of patients with ICH.
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Hemorragia Cerebral , Transplante de Células-Tronco Mesenquimais , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Hemorragia Cerebral/terapia , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , AdultoRESUMO
OBJECTIVES: The aim of this study was to evaluate the impact of continuity of care on older adults diagnosed with mental and behavioural disorders who are at risk of death due to intentional self-harm. STUDY DESIGN: This was a retrospective cohort study. METHODS: Data from the Korean National Health Insurance Service-Elderly Cohort Database (2002-2013) were used. A total of 53,980 patients who had visited the outpatient clinic three or more times within the year following the initial diagnosis of mental and behavioural disorders were included. A generalised estimating equation model was generated to examine the impact of continuity of care (CoC) on the risk of death due to intentional self-harm among older adults with mental illnesses. RESULTS: The risk of death due to intentional self-harm was significantly higher in those with poor CoC for mental and behavioural disorders than in those with good CoC. The risk ratio, adjusting for all covariates, was larger for the Usual Provider of Care index (adjusted risk ratio [aRR]: 1.63, 95% confidence interval [CI]: 1.25-2.12) than for the CoC index (aRR: 1.50, 95% CI: 1.18-1.90), indicating a stronger association with the concentration of contact with the most frequently visited provider. CONCLUSIONS: Poor CoC among Korean older adults diagnosed with mental and behavioural disorders was identified as a significant risk factor for death due to intentional self-harm. The results of this study highlight the need for interventions that can prevent suicidal behaviour in older adults, such as institutionalising the usual providers of mental health care for older adults.
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Transtornos Mentais , Comportamento Autodestrutivo , Humanos , Idoso , Estudos Retrospectivos , Estudos de Coortes , Transtornos Mentais/epidemiologia , Comportamento Autodestrutivo/epidemiologia , Comportamento Autodestrutivo/psicologia , Continuidade da Assistência ao Paciente , República da Coreia/epidemiologiaRESUMO
Elbow stiffness is a common consequence of trauma and can significantly limit the functionality of the affected arm. Intervention may be necessary for those with a motion arc less than 100°, but the decision to intervene should be based on individual patient needs. Restoration of joint motion in a stiff elbow can be challenging, time consuming, and costly. Nonsurgical treatment is the primary management option, and surgical intervention is considered for refractory stiffness. However, recurrent stiffness is a common issue following surgical elbow contracture release. An overview of relevant elbow anatomy, principles and technical pearls of arthroscopic and open contracture release, and postoperative rehabilitation methods to reduce the risk of recurrent stiffness is provided. It is important to tailor the treatment plan to each patient's unique needs and functional expectations.
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Contratura , Articulação do Cotovelo , Humanos , Braço , Artroscopia , Contratura/etiologia , Contratura/cirurgia , Cotovelo , Articulação do Cotovelo/cirurgia , Amplitude de Movimento ArticularRESUMO
BACKGROUND: Although forward elevation, abduction, and external rotation are often successfully restored, internal rotation (IR) is frequently not satisfactorily recovered following reverse shoulder arthroplasty (RSA), affecting patients' ability to perform certain daily activities. This study examined the prevalence of limited IR in patients receiving modern RSA and its impact on clinical outcomes and patient satisfaction with their RSA. METHODS: A cross-sectional study was conducted on patients who had undergone primary RSA using a modern RSA prosthesis with a minimum 1-year follow-up. Patients returned for a research visit where they were examined for range of motion and surveyed for patient-reported outcome measures (PROMs) and subjective rating of the success level of their RSA. Postoperative range of motion data were compared with the preoperative data. The relationship of postoperative IR with PROMs and patients' subjective rating of RSA was analyzed. Logistic regression was performed to identify factors affecting patients' subjective rating of RSA. RESULTS: A total of 78 patients met the criteria and completed the study. A significant portion (59%) reported subjective IR limitations, and 41% had objective IR limitations. Comparison of preoperative and postoperative IR showed that 24% had worsened IR, whereas 33% improved. Limited IR was associated with lower patients' subjective rating of RSA and negatively affected PROMs, especially when the dominant side was operated on. Regression analysis showed that limited IR was the only independent determining factor that was significantly associated with a lower subjective rating of RSA. DISCUSSION: Despite advancements in RSA design, limited IR remains a prevalent issue, significantly affecting patients' satisfaction and clinical outcomes. This study underscores the need for setting appropriate expectations regarding IR through patient education and focused efforts to improve IR limitations in RSA patients, particularly on the dominant side.
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BACKGROUND: Cutibacterium acnes remains the most commonly detected organism in shoulder arthroplasty. C acnes infection is thought to occur during shoulder arthroplasty through contamination of the surgical field with C acnes from the incised dermis. The purpose of this study was to examine whether using electrocautery for making skin incisions would decrease C acnes culture rates at the incised dermis compared to using scalpels during shoulder arthroplasty. METHODS: Patients undergoing primary shoulder arthroplasty were randomized into 2 groups, electrocautery vs. scalpel incision group. All patients received a standard preoperative antiseptic preparation including chlorhexidine gluconate showers, intravenous antibiotic administration, and topical application of hydrogen peroxide, povidone iodine, isopropyl alcohol, and DuraPrep. Cultures were obtained from the incised dermal edge immediately after skin incision and later from surgeon's gloves and forceps immediately prior to humeral component implantation. The primary outcome was positive C acnes culture rates compared between the groups. RESULTS: A total of 64 patients (32 in each group) were enrolled. There were 24 males in each group. Regarding dermis cultures, 10 patients (31%) in the scalpel group were positive with 8 of them positive for C acnes, whereas no patients in the electrocautery group were positive (P < .001). Regarding glove cultures, the electrocautery group had 8 patients positive C acnes, while the scalpel group had 8 (P = .777). Regarding forceps cultures, the electrocautery group had 4 patients positive for C acnes, and the scalpel group had 6 (P = .491). All positive cultures were exclusively from male patients. There were no wound complications or infection in the electrocautery group while the scalpel group had 1 acute postoperative infection. CONCLUSIONS: Making skin incisions using electrocautery resulted in 0 C acnes culture at the incised dermis, suggesting its potential effect against C acnes. However, despite this initial antibacterial effect, C acnes still appeared on surgeon's gloves and forceps during surgery of male patients. All positive cultures were from male patients, suggesting that the source of C acnes was specifically related to the male body. While the study hypothesis was supported by the results, the present study also raises new questions and calls for further research.
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Anti-Infecciosos Locais , Artroplastia do Ombro , Articulação do Ombro , Humanos , Masculino , Artroplastia do Ombro/efeitos adversos , Articulação do Ombro/cirurgia , Articulação do Ombro/microbiologia , Pele/microbiologia , Estudos Prospectivos , Propionibacterium acnes , Antibacterianos/uso terapêuticoRESUMO
AIM: To compare the biomechanical properties of three different sternal closure techniques in a 3D-printed bone model of a sternum from a 30-kg dog. METHODS: Median sternotomy was performed on a total of 90 three-dimensional (3D) copies of a polycarbonate (PC) model of a sternum, generated from the CT images of the sternum of a 30-kg German Shepherd dog. Three different methods were used to repair the sternotomies: polydioxanone suture (group PDS, n = 30), stainless steel bone staples (group SS, n = 30), and nitinol bone staples (group NS, n = 30). Each repair method was tested by applying tensile force in one of three ways (longitudinally, laterally, or torsionally) resulting in a sample size of n = 10 for each repair method-loading combination. In all experiments, the loads at 1-mm and 2-mm gap formation, failure, and the displacement at the failure point were measured. RESULTS: In lateral distraction and longitudinal shear tests, NS and SS staple repairs required application of significantly greater force than PDS across all displacement criteria (1 and 2 mm). NS exhibited significantly greater failure load than PDS. In torsion tests, NS required significantly greater application of force compared to SS or PDS at all displacement criteria (1 and 2 mm) and exhibited a greater failure load than PDS. In terms of displacement at failure point, PDS suture showed more displacement than SS or NS across all experiments (laterally, longitudinally, torsionally). CONCLUSIONS: In this study, bone staples were mechanically superior to PDS suture in median sternotomy closure using 3D-printed bone model in terms of 1-mm, 2-mm displacement loads, and displacement at failure. NS had a higher failure load than PDS under lateral, longitudinal, and torsional distraction. CLINICAL RELEVANCE: These study results imply that bone staples can be considered as an alternative surgical method for median sternotomy closure in dogs.
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Impressão Tridimensional , Esternotomia , Suturas , Animais , Suturas/veterinária , Cães , Fenômenos Biomecânicos , Esternotomia/veterinária , Esternotomia/métodos , Grampeamento Cirúrgico/veterinária , Grampeamento Cirúrgico/métodos , Grampeamento Cirúrgico/instrumentação , Esterno/cirurgia , Modelos Anatômicos , Técnicas de Sutura/veterináriaRESUMO
1. The study evaluated the effect of dietary metabolisable energy (ME) content and crude protein (CP) level on the growth performance and behaviour of ducks.2. A total of 720, Cherry Valley ducks were allocated to 36 pens in groups of 20 birds. For the initial period, from 1 to 21 d age, six diets, containing a standard (SME), low (LME) and high (HME) ME of 12.14, 11.93 and 12.35 MJ/kg, and standard (SCP) or high (HCP) CP contents of 210 or 220 g/kg diet, respectively, were mixed. For the period from 22 to 42 d age, the diets contained ME of 12.98 (SME), 12.77 (LME), 13.19 (HME) MJ/kg and the levels of CP were 170 (SCP) or 180 (HCP) g/kg, respectively.3. An ME by CP interaction was seen from 1 to 21 d age in ducks fed HME + HCP diet, which had greater weight gain than those fed LME + SCP (P < 0.05). Compared to LME + SCP, dietary HME decrease feeding but increased walking behaviour compared to LME + SCP and SME + SCP (P < 0.05). High CP in LME and SME diets increased drinking behaviour (P < 0.05), but there was no change in HME diet. Compared to LME, feeding HME reduced ground pecking (P < 0.05). Feeding HME reduced feeding behaviour (P < 0.05) from 22 to 42 d age. During the same period, standing behaviour was reduced in HCP + LME (P < 0.05). Drinking was reduced in LME + SCP compared to SME + HCP and HME + HCP (P < 0.05).4. A diet formulated with HME and HCP is effective for enhancing growth performance of ducks aged 1-21 d and saving time for feeding or ground pecking, which may induce spending more time on other activities.
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Galinhas , Patos , Animais , Fenômenos Fisiológicos da Nutrição Animal , Dieta/veterinária , Aumento de PesoRESUMO
Tandem mass spectrometry (MS/MS) using fragmentation has become one of the most effective methods for gaining sequence and structural information on biomolecules. Ion/ion reactions are competitive reactions, where either proton transfer (PT) or electron transfer (ET) can occur from interactions between multiply charged cations and singly charged anions. Utilizing ion/ion reactions with fluoranthene has offered a unique method of fragment formation for the structural elucidation of biomolecules. Fluoranthene is considered an ideal anion reagent because it selectively causes electron-transfer dissociation (ETD) and minimizes PT when interacting with peptides. However, limited investigations have sought to understand how fluorantheneâthe primary, commercially available anion reagentâinteracts with other biomolecules. Here, we apply deuterium labeling to investigate ion/ion reaction mechanisms between fluoranthene and divalent, metal-adducted carbohydrates (Ca2+, Mg2+, Co2+, and Ni2+). Deuterium labeling of carbohydrates allowed us to observe evidence of hydrogen/deuterium exchange (HDX) occurring after ion/ion dissociation reactions. The extent of deuterium loss is dependent on several factors, including the physical properties of the metal ion and the fragment structure. Based on the deuterium labeling data, we have proposed ETD, PTD, and intermolecular PTâalso described as HDXâmechanisms. This research provides a fundamental perspective of ion/ion and ion/molecule reaction mechanisms and illustrates properties that impact ion/ion and ion/molecule reactions for carbohydrates. Together, this could improve the capability to distinguish complex and heterogeneous biomolecules, such as carbohydrates.