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BACKGROUND: Textbook outcomes is a composite quality assurance tool assessing the ideal perioperative and postoperative course as a unified measure. Currently, its definition and application in the context of oesophagectomy in Australia is unknown. The aim of this study was to assess the textbook outcomes after oesophagectomy in a single referral centre of Australia and investigate the association between textbook outcomes and patient, tumour, and treatment characteristics. METHODS: An observational study was retrospectively performed on patients undergoing open, laparoscopic, or hybrid oesophagectomy between January 2010 and December 2019 in a single cancer referral centre. A textbook outcome was defined as the fulfillment of 10 criteria: R0 resection, retrieval of at least 15 lymph nodes, no intraoperative complications, no postoperative complications greater than Clavien-Dindo grade III, no anastomotic leak, no readmission to the ICU, no hospital stay beyond 21 days, no mortality within 90 days, no readmission related to the surgical procedure within 30 days from admission and no reintervention related to the surgical procedure. The proportion of patients who met each criterion for textbook outcome was calculated and compared. Selected patient-related parameters (age, gender, BMI, ASA score, CCI score), tumour-related factors (tumour location, tumour histology, AJCC clinical T and N stage and treatment-related factor [neoadjuvant chemotherapy and surgical approach]) were assessed. Disease recurrence and one year survival were also evaluated. RESULTS: 110 patients who underwent oesophagectomy were included. The overall textbook outcome rate was 24%. The difference in rates across the years was not statistically significant. The most achieved textbook outcome parameters were 'no mortality in 90 days' (96%) and 'R0 resection' (89%). The least frequently met textbook outcome parameter was 'no severe postoperative complications' (58%), followed by 'no hospital stays over 21 days' (61%). No significant association was found between patient, tumour and treatment characteristics and the rate of textbook outcome. Tumour recurrence rate and overall long term survival was similar between textbook outcome and non-textbook outcome groups. Patients with R0 resection, no intraoperative complication and a hospital stay less than 21 days had reduced mortality rates. CONCLUSIONS: Textbook outcome is a clinically relevant indicator and was achieved in 24% of patients. Severe complications and a prolonged hospital stay were the key criteria that limited the achievement of a textbook outcome. These findings provide meticulous evaluation of oesophagectomy perioperative care and provide a direction for the utilisation of this concept in identifying and improving surgical and oncological care across multiple healthcare levels.
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Neoplasias Esofágicas , Esofagectomia , Humanos , Estudos Retrospectivos , Esofagectomia/efeitos adversos , Recidiva Local de Neoplasia/cirurgia , Complicações Pós-Operatórias/etiologia , Fístula Anastomótica/etiologia , Complicações Intraoperatórias/etiologia , Resultado do TratamentoRESUMO
OBJECTIVE: To evaluate neck muscle coactivation across different levels of mental workload during simulated flight tasks. BACKGROUND: Neck pain (NP) is highly prevalent among military aviators. Given the complex nature within the flight environment, mental workload may be a risk factor for NP. This may induce higher levels of neck muscle coactivity, which over time may accelerate fatigue, increase neck discomfort, and affect flight task performance. METHOD: Three counterbalanced mental workload conditions represented by simulated flight tasks modulated by interstimulus frequency and complexity were investigated using the Modifiable Multitasking Environment (ModME). The primary measure was a neck coactivation index to describe the neuromuscular effort of the neck muscles as a system. Additional measures included perceived workload (NASA TLX), subjective discomfort, and task performance. Participants (n = 60; 30M, 30F) performed three test conditions over 1 hr each while seated in a simulated seating environment. RESULTS: Neck coactivation indices (CoA) and subjective neck discomfort corresponded with increasing level of mental workload. Average CoAs for low, medium, and high workloads were: .0278(SD = .0232), .0286(SD = .0231), and .0295(SD = .0228), respectively. NASA TLX mental, temporal, effort, and overall scores also increased with the level of mental workload assigned. For ModME task performance, the overall performance score, monitoring accuracy, and resource management accuracy decreased while reaction times increased with the increasing level of mental workload. Communication accuracy was lowest with the low mental workload but had higher reaction times relative to increasing workload. CONCLUSION: Mental workload affects neck muscle coactivation during combinations of simulated flight tasks within a simulated helicopter seating environment. APPLICATION: The results of this study provide insights into the physical response to mental workload. With increasing multisensory modalities within the work environment, these insights may assist the consideration of physical effects from cognitive factors.
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OBJECTIVE: Assess neck muscle activity for varying interactions between helmet, posture, and visual stress in a simulated "helo-hunch" posture. BACKGROUND: Military aviators frequently report neck pain (NP). Risk factors for NP include head-supported mass, awkward postures, and mental workload. Interactions between these factors could induce constant low-level muscle activation during helicopter flight and better explain instances of NP. METHOD: Interactions between physical loading (helmet doffed/donned), posture (symmetric/asymmetric), and visual stress (low/high contrast) were studied through neck muscle electromyography (EMG), head kinematics, subjective discomfort, perceived workload, and task performance. Subjects (n = 16) performed eight 30-min test conditions (varied physical loading, posture, and visual stress) while performing a simple task in a simulated "helo-hunch" seating environment. RESULTS: Conditions with a helmet donned had fewer EMG median frequency cycles (which infer motor unit rotation for rest/recovery, where more cycles are better) in the left cervical extensor and left sternocleidomastoid. Asymmetric posture (to the right) resulted in higher normalized EMG activity in the right cervical extensor and left sternocleidomastoid and resulted in less lateral bending compared with neutral across all conditions. Conditions with high visual stress also resulted in fewer EMG cycles in the right cervical extensor. CONCLUSION: A complex interaction exists between the physical load of the helmet, postural stress from awkward postures, and visual stress within a simulated "helo-hunch" seating environment. APPLICATION: These results provide insight into how visual factors influence biomechanical loading. Such insights may assist future studies in designing short-term administrative controls and long-term engineering controls.
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Músculos do Pescoço , Postura , Humanos , Músculos do Pescoço/fisiologia , Postura/fisiologia , Aeronaves , Pescoço , Eletromiografia , CervicalgiaRESUMO
BACKGROUND: Haptoglobin (Hp) genotype has been linked to oxidative stress and cardiovascular outcomes in response to vitamin E (VitE) among patients with diabetes mellitus. Its effect on histologic response to VitE in nonalcoholic steatohepatitis (NASH) is unknown. GOALS: Our objective was to determine if Hp genotype associates with response to VitE in patients with NASH. STUDY: A post hoc analysis of 228 patients receiving VitE or placebo in 2 clinical trials was performed. Regression analysis was used to assess the effect of VitE versus placebo, by Hp genotype (1-1, 2-1, or 2-2), on histologic features and laboratory markers of nonalcoholic fatty liver disease, comparing baseline to end of treatment values. An interaction term was included in the regression models to assess differential treatment effect across Hp genotype. RESULTS: Hp 2-2 patients treated with VitE versus placebo showed significant histologic improvement (51% vs. 20%; OR=4.2; P=0.006), resolution of steatohepatitis (44% vs. 12%; OR=6.2; P=0.009), decrease in nonalcoholic fatty liver disease Activity Score (NAS) (-2.2 vs. -0.6; P=0.001), and decrease in liver enzymes alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transpeptidase. Hp 2-1 patients on VitE versus placebo showed improved resolution of steatohepatitis, NAS and liver enzymes. Hp 1-1 patients showed no significant improvement in histology or liver enzymes. VitE had no effect on fibrosis stage in any group. Regression analysis showed incremental benefit of having Hp 2-2 or 2-1 versus 1-1 for all liver enzyme. CONCLUSIONS: Hp 2 allele is associated with greater histologic and biological improvement in NASH with VitE treatment compared with the Hp 1 allele.
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Haptoglobinas/genética , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Vitamina E/uso terapêutico , Adulto , Alelos , Feminino , Genótipo , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Vitamina E/administração & dosagemRESUMO
Objective Develop a coactivation index for the neck and test its effectiveness with complex dynamic head motions. Background Studies describing coactivation for the cervical spine are sparse in the literature. Of those in existence, they were either limited to a priori definitions of agonist/antagonist activity that limited the testing to sagittal and lateral planes or consisted of isometric exertions. Multiplanar movements would allow for a more realistic understanding of naturalistic movements in the cervical spine and propensity for neck pain. However, a gap in the literature exists in which a method to describe coactivation during complex dynamic motions does not exist for the cervical spine. Methods An electromyography-based coactivation index was developed for the cervical spine based on previously tested methodology used on the lumbar spine without a high-end model and tested using a series of different postures and speeds. Results Complex motions involving twisting (i.e., flexion and twisting) and higher speed had higher magnitudes of coactivation than uniplanar motions in the sagittal or lateral plane, which was expected. The coupled motion of flexion and twisting showed four to five times higher coactivation than uniplanar (sagittal or lateral) movements. Conclusion The coactivation index developed accommodates multiplanar, naturalistic movements. Testing of the index showed that motions requiring higher degrees of head control had higher effort due to coactivation, which was expected. Application Overall, this coactivation index may be utilized to understand the neuromuscular effort of various tasks in the cervical spine.
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Vértebras Cervicais/fisiologia , Eletromiografia/métodos , Músculos do Pescoço/fisiologia , Cervicalgia/fisiopatologia , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Adulto JovemRESUMO
The objective of this study was to develop and test an EMG-based coactivation index and compare it to a coactivation index defined by a biologically assisted lumbar spine model to differentiate between tasks. The purpose was to provide a universal approach to assess coactivation of a multi-muscle system when a computational model is not accessible. The EMG-based index developed utilised anthropometric-defined muscle characteristics driven by torso kinematics and EMG. Muscles were classified as agonists/antagonists based upon 'simulated' moments of the muscles relative to the total 'simulated' moment. Different tasks were used to test the range of the index including lifting, pushing and Valsalva. Results showed that the EMG-based index was comparable to the index defined by a biologically assisted model (r2 = 0.78). Overall, the EMG-based index provides a universal, usable method to assess the neuromuscular effort associated with coactivation for complex dynamic tasks when the benefit of a biomechanical model is not available. Practitioner Summary: A universal coactivation index for the lumbar spine was developed to assess complex dynamic tasks. This method was validated relative to a model-based index for use when a high-end computational model is not available. Its simplicity allows for fewer inputs and usability for assessment of task ergonomics and rehabilitation.
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Modelos Biológicos , Contração Muscular , Músculo Esquelético/fisiologia , Músculos Abdominais Oblíquos/fisiologia , Adulto , Fenômenos Biomecânicos/fisiologia , Eletromiografia , Feminino , Humanos , Remoção , Região Lombossacral , Masculino , Músculos Paraespinais/fisiologia , Reto do Abdome/fisiologia , Músculos Superficiais do Dorso/fisiologia , Manobra de Valsalva/fisiologia , Adulto JovemRESUMO
The objective of this study was to identify biomechanical measures that can distinguish texting distraction in a laboratory-simulated driving environment. The goal would be to use this information to provide an intervention for risky driving behaviour. Sixteen subjects participated in this study. Three independent variables were tested: task (texting, visual targeting, weighted and non-weighted movements), task direction (front and side) and task distance (close and far). Dependent variables consisted of biomechanical moments, head displacement and the length of time to complete each task. Results revealed that the time to complete each task was higher for texting compared to other tasks. Peak moments during texting were only distinguishable from visual targeting. Peak head displacement and cumulative biomechanical exposure measures indicated that texting can be distinguished from other tasks. Therefore, it may be useful to take into account both temporal and biomechanical measures when considering warning systems to detect texting distraction.
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Simulação por Computador , Direção Distraída , Envio de Mensagens de Texto , Interface Usuário-Computador , Adulto , Fenômenos Biomecânicos , Telefone Celular , Feminino , Cabeça , Humanos , Masculino , Movimento , Assunção de Riscos , Adulto JovemRESUMO
Chemical and thermal denaturation of dehaloperoxidase-hemoglobin (DHP) was investigated to test the relative stability of isoforms DHP A and DHP B and the H55V mutant of DHP A with respect to heme loss. In thermal denaturation experiments, heme loss was observed at temperatures of 54, 46, and 61 °C in DHP A, DHP B, and H55V, respectively. Guanidinium hydrochloride (GdnHCl)- and urea-induced denaturation was observed at respective concentrations of 1.15 ± 0.01 M DHP A and 1.09 ± 0.02 M DHP B, and 5.19 ± 0.05 M DHP A and 4.12 ± 0.14 M DHP B, respectively. The binding affinity of heme appears to be significantly smaller in both isoforms of DHP than in myoglobins. This observation was corroborated by heme transfer experiments, in which heme was observed to transfer for DHP A and B to horse skeletal muscle myoglobin (HSMb). GdnHCl-induced denaturation suggests a threshold of 1 mM for stabilization by binding of the inhibitor 4-bromophenol (4-BP). Concentrations of 4-BP greater than 1 mM caused destabilization. Urea-induced denaturation showed only destabilizing effects from phenolic ligand binding. Heme transfer experiments from DHP to HSMb further support the hypothesis that the binding of halophenols to DHP facilitates the removal of the heme. Thermal denaturation assessed via UV-visible spectroscopy and that assessed by differential scanning calorimetry (DSC) are both in agreement with chemical denaturation experiments and show that the denaturing abilities of the halophenols improve with the size of the para halogen atom in 4-XP, where X = iodo, bromo, chloro, or fluoro (4-IP > 4-BP > 4-CP > 4-FP), and the number of halo substituents as in 2,4,6-tribromophenol (2,4,6-TBP > 4-BP). DHP B, which differs in five amino acids, is less stable than DHP A with ΔHcal and Tm values of 165.1 kJ/mol and 47.5 °C compared to values of 183.3 kJ/mol and 50.4 °C for DHP B and DHP A, respectively. Kinetic studies verified that DHP B has a catalytic efficiency (kcat/Km) â¼5-6 times greater than that of DHP A but showed an increased level of substrate inhibition in DHP B for both 2,4,6-TCP and 2,4,6-TBP. An inverse correlation between protein stability with respect to heme loss and catalytic efficiency is suggested on the basis of the fact that the heme in DHP B has a stability lower than that of DHP A but a catalytic efficiency higher than that of DHP A.
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Heme/química , Hemoglobinas/química , Peroxidases/química , Animais , Cinética , Poliquetos/enzimologia , Ligação Proteica , Desnaturação Proteica , TermodinâmicaRESUMO
The objective of this study was to identify how physiological measures relate to self-reported vehicle seating discomfort. Twelve subjects of varied anthropometric characteristics were enrolled in the study. Subjects sat in two seats over a 2-h period and were evaluated via three physiological measures (near-infrared spectroscopy, electromyography and pressure mapping) yielding six testing sessions. Subjective discomfort surveys were recorded before and after each session for nine regions of the body. Conditional classification discomfort models were developed through dichotomised physiological responses and anthropometry to predict subjective discomfort in specific body locations. Models revealed that subjects taller than 171 cm with reduced blood oxygenation in the biceps femoris or constant, low-level muscle activity in the trapezius tended to report discomfort in the lower extremities or neck, respectively. Subjects weighing less than 58 kg with reduced blood oxygenation in the biceps femoris or unevenly distributed pressure patterns tended to report discomfort in the buttocks. The sensitivities and specificities of cross-validated models ranged between 0.69 and 1.00.
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Automóveis , Desenho de Equipamento , Dor Musculoesquelética/prevenção & controle , Fenômenos Fisiológicos Musculoesqueléticos , Postura , Adolescente , Adulto , Nádegas , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético , Dor Musculoesquelética/fisiopatologia , Pescoço , Pressão , Espectroscopia de Luz Próxima ao Infravermelho , Adulto JovemRESUMO
BACKGROUND: Cost analyses of patients undergoing esophagectomy is valuable for identifying modifiable expenditure drivers to target and curtail costs while improving the quality of care. We aimed to define the cost-complication relationship after esophagectomy and delineate the incremental contributions to costs. AIM: To assess the relationship between the hospital costs and potential cost drivers post esophagectomy and investigate the relationship between the cost-driving variables (predicting variables) and hospital costs (dependent variable). METHODS: In this retrospective single center study, the severity of complications was graded using the Clavien-Dindo (CD) classification system. Key esophagectomy complications were categorized and defined according to consensus guidelines. Raw costing data included the in-hospital costs of the index admission and any unplanned admission within 30 postoperative days. We used correlation analysis to assess the relationship between key clinical variables and hospital costs (in United States dollars) to identify cost drivers. A mediation model was used to investigate the relationship between these variables and hospital costs. RESULTS: A total of 110 patients underwent primary esophageal resection. The median admission cost was $47822.7 (interquartile range: 35670.2-68214.0). The total effects on costs were $13593.9 (95%CI: 10187.1-17000.8, P < 0.001) for each increase in CD severity grade, $4781 (95%CI: 3772.7-5789.3, P < 0.001) for each increase in the number of complications, and $42552.2 (95%CI: 8309-76795.4, P = 0.015) if a key esophagectomy complication developed. Key esophagectomy complications drove the costs directly by $11415.7 (95%CI: 992.5-21838.9, P = 0.032). CONCLUSION: The severity and number of complications, and the development of key esophagectomy complications significantly contributed to total hospital costs. Continuous institutional initiatives and strategies are needed to enhance patient outcomes and minimize costs.
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Background: The concept of a "textbook outcome" is emerging as a metric for ideal surgical outcomes. We aimed to evaluate the impact of an advanced haemodynamic monitoring (AHDM) algorithm on achieving a textbook outcome in patients undergoing hepatobiliary-pancreatic surgery. Methods: This retrospective, multicentre observational study was conducted across private and public teaching sectors in Victoria, Australia. We studied patients managed by a patient-specific, surgery-specific haemodynamic algorithm or via usual care. The primary outcome was the effect of using a patient-specific, surgery-specific AHDM algorithm for achieving a textbook outcome, with adjustment using propensity score matching. The textbook outcome criteria were defined according to the International Expert Delphi Consensus on Defining Textbook Outcome in Liver Surgery and Nationwide Analysis of a Novel Quality Measure in Pancreatic Surgery. Results: Of the 780 weighted cases, 477 (61.2%, 95% CI: 57.7%-64.6%) achieved the textbook outcome. Patients in the AHDM group had a higher rate of textbook outcomes [n = 259 (67.8%)] than those in the Usual care group [n = 218 (54.8%); p < 0.001, estimated odds ratio (95% CI) 1.74 (1.30-2.33)]. The AHDM group had a lower rate of surgery-specific complications, severe complications, and a shorter hospital length of stay (LOS) [OR 2.34 (95% CI: 1.30-4.21), 1.79 (95% CI: 1.12-2.85), and 1.83 (95% CI: 1.35-2.46), respectively]. There was no significant difference between the groups for hospital readmission and mortality. Conclusions: AHDM use was associated with improved outcomes, supporting its integration in hepatobiliary-pancreatic surgery. Prospective trials are warranted to further evaluate the impact of this AHDM algorithm on achieving a textbook impact on long-term outcomes.
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OBJECTIVE: The unprecedented events of 2020 required a pivot in scientific training to better prepare the biomedical research workforce to address global pandemics, structural racism, and social inequities that devastate human health individually and erode it collectively. Furthermore, this pivot had to be accomplished in the virtual environment given the nation-wide lockdown. METHODS: These needs and context led to leveraging of the San Francisco Building Infrastructure Leading to Diversity (SF BUILD) theories of change to innovate a Virtual BUILD Research Collaboratory (VBRC). The purpose of VBRC was to train Black, Indigenous, and people of color (BIPOC) students to apply their unique perspectives to biomedical research. These training activities were evaluated using a pre-post survey design that included both validated and new psychosocial scales. A new scale was piloted to measure culturally relevant pedagogy. RESULTS: VBRC scholars increased science identity on two items: thinking of myself as a scientist (+1point, p = 0.006) and belonging to a community of scientists (+1point, p = 0.069). Overall, scholars perceived stress also decreased over VBRC (-2.35 points, p = 0.02). Post VBRC, scholars had high agency scores (µ = 11.02, Md = 12, range = 6-12, σ = 1.62) and cultural humility scores (µ = 22.11, Md = 23, range = 12-24, σ = 2.71). No notable race/ethnic differences were found in any measures. CONCLUSIONS: Taken together, our innovative approach to data science training for BIPOC in unprecedented times shows promise for better preparing the workforce critically needed to address the fundamental gaps in knowledge at the intersection of public health, structural racism, and biomedical sciences.
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Pesquisa Biomédica , Racismo , Humanos , Racismo/prevenção & controle , Ciência de Dados , Recursos Humanos , Pesquisa Biomédica/educação , EstudantesRESUMO
BACKGROUND: An optimal pharmacological strategy for fast-track cardiac anesthesia (FTCA) is unclear. This study evaluated the effectiveness and safety of an FTCA program using methadone and non-opioid adjuvant infusions (magnesium, ketamine, lidocaine, and dexmedetomidine) in patients undergoing coronary artery bypass grafting. METHODS: This retrospective, multicenter observational study was conducted across private and public teaching sectors. We studied patients managed by a fast-track protocol or via usual care according to clinician preference. The primary outcome was the total mechanical ventilation time in hours adjusted for hospital, body mass index, category of surgical urgency, cardiopulmonary bypass time and EuroSCORE II. Secondary outcomes included successful extubation within four postoperative hours, postoperative pain scores, postoperative opioid requirements, and the development of postoperative complications. RESULTS: We included 87 patients in the fast-track group and 88 patients in the usual care group. Fast-track patients had a 35% reduction in total ventilation hours compared with usual care patients (p = 0.007). Thirty-five (40.2%) fast-track patients were extubated within four hours compared to 10 (11.4%) usual-care patients (odds ratio: 5.2 [95% CI: 2.39-11.08; p < 0.001]). Over 24 h, fast-track patients had less severe pain (p < 0.001) and required less intravenous morphine equivalent (22.00 mg [15.75:32.50] vs. 38.75 mg [20.50:81.75]; p < 0.001). There were no significant differences observed in postoperative complications or length of hospital stay between the groups. CONCLUSION: Implementing an FTCA protocol using methadone, dexmedetomidine, magnesium, ketamine, lignocaine, and remifentanil together with protocolized weaning from a mechanical ventilation protocol is associated with significantly reduced time to tracheal extubation, improved postoperative analgesia, and reduced opioid use without any adverse safety events. A prospective randomized trial is warranted to further investigate the combined effects of these medications in reducing complications and length of stay in FTCA. TRIALS REGISTRATION: The study protocol was registered in the Australian New Zealand Clinical Trials Registry ( https://www.anzctr.org.au/ACTRN12623000060640.aspx , retrospectively registered on 17/01/2023).
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Ponte de Artéria Coronária , Dexmedetomidina , Ketamina , Lidocaína , Metadona , Dor Pós-Operatória , Humanos , Masculino , Feminino , Estudos Retrospectivos , Ponte de Artéria Coronária/métodos , Ponte de Artéria Coronária/efeitos adversos , Metadona/uso terapêutico , Metadona/administração & dosagem , Dexmedetomidina/administração & dosagem , Dexmedetomidina/uso terapêutico , Ketamina/administração & dosagem , Ketamina/uso terapêutico , Pessoa de Meia-Idade , Idoso , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Lidocaína/administração & dosagem , Lidocaína/uso terapêutico , Magnésio/administração & dosagem , Analgésicos Opioides/uso terapêutico , Analgésicos Opioides/administração & dosagem , Resultado do TratamentoRESUMO
X-ray crystal structures of dehaloperoxidase-hemoglobin A (DHP A) from Amphitrite ornata soaked with substrate, 2,4,6-tribromophenol (2,4,6-TBP), in buffer solvent with added methanol (MeOH), 2-propanol (2-PrOH), and dimethyl sulfoxide (DMSO) reveal an internal substrate binding site deep in the distal pocket above the α-edge of the heme that is distinct from the previously determined internal inhibitor binding site. The peroxidase function of DHP A has most often been studied using 2,4,6-trichlorophenol (2,4,6-TCP) as a substrate analogue because of the low solubility of 2,4,6-TBP in an aqueous buffer solution. Previous studies at low substrate concentrations pointed to the binding of substrate 2,4,6-TCP at an external site near the exterior heme ß- or δ-edge as observed in the class of heme peroxidases. Here we report that the turnover frequencies of both substrates 2,4,6-TCP and 2,4,6-TBP deviate from Michaelis-Menten kinetics at high concentrations. The turnover frequency reaches a maximum in the range of 1400-1700 µM, with a decrease in rate at higher concentrations that is both substrate- and solvent-dependent. The X-ray crystal structure is consistent with the presence of an internal active site above the heme α-edge, in which the substrate would be oxidized in two consecutive steps inside the enzyme, followed by attack by H2O via a water channel in the protein. The physiological role of the internal site may involve interactions with any of a number of aromatic toxins found in benthic ecosystems where A. ornata resides.
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Hemoglobinas/química , Peroxidases/química , Poliquetos/enzimologia , 2-Propanol/química , Animais , Cristalografia por Raios X , Dimetil Sulfóxido/química , Hemoglobinas/metabolismo , Cinética , Metanol/química , Modelos Moleculares , Peroxidases/metabolismo , Fenóis/química , Poliquetos/química , Poliquetos/metabolismo , Conformação ProteicaRESUMO
INTRODUCTION: The rapid rise in the incidence of oesophageal adenocarcinoma has resulted in an increasing number of patients undergoing oesophagectomy. Although novel surgical techniques are enhancing surgical outcomes, postoperative complications remain pervasive. Despite this, there are limited reviews mapping the cost of postoperative complications following oesophagectomy, and none has compared cost differences between patient groups. Such information would be invaluable in appreciating the financial burden on the healthcare system and serving to guide hospital financing decisions. This scoping review protocol outlines an approach to reviewing the literature to precipitate and inform discussions surrounding financing oesophagectomy procedures as well as funding requirements for upper gastrointestinal surgical units. METHODS AND ANALYSIS: Adhering to the pertinent components of the Preferred Reporting Items for Systematic Review and Meta-Analysis Extension for Scoping Review Protocols guidelines, a systematic exploration will be conducted across electronic databases, including MEDLINE, EMBASE, the Cochrane Library and Econolit, with further reference tracking of eligible studies. This review will encompass studies related to the costs associated with complications following oesophagectomy. All studies published prior to 31 October 2023 are eligible for inclusion. The process of screening and extracting data will be undertaken by two independent reviewers. Subsequently, the amassed data will be pooled and subjected to comprehensive analysis and presented descriptively, using both a mixed methods and a narrative approach. ETHICS AND DISSEMINATION: Ethics approval was not required. The results will be communicated through established professional networks, conference presentations and publication in peer-reviewed journals.
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Adenocarcinoma , Esofagectomia , Humanos , Esofagectomia/efeitos adversos , Esofagectomia/métodos , Estresse Financeiro , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Projetos de Pesquisa , Adenocarcinoma/cirurgia , Adenocarcinoma/complicações , Metanálise como Assunto , Revisões Sistemáticas como AssuntoRESUMO
PURPOSE: We recently showed that in situ-forming collagen gels crosslinked through multifunctional polyethylene glycol (PEG) supported corneal epithelialization 7 days after treatment of lamellar keratectomy wounds. In this study, we aimed to evaluate the longer-term regenerative effects of this gel in animals. METHOD: Corneal wound healing was assessed 60 days after lamellar keratectomy and gel treatment using slitlamp examination, optical coherence tomography (OCT), pachymetry, corneal topography, an ocular response analyzer, and tonometry. The corneas were evaluated for the presence of beta-tubulin, cytokeratin 3, zonula occludens-1, and alpha smooth muscle actin (SMA) markers. Gene expression of aldehyde dehydrogenase 3A1 (ALDH3A1), cluster of differentiation 31, CD163, alpha-SMA, hepatocyte growth factor, and fibroblast growth factor 2 (FGF-2) and protein expression of CD44 and collagen VI were evaluated. RESULTS: Intraocular pressure, corneal thickness, and hysteresis for the corneas treated with collagen-PEG gels did not significantly change compared with the saline group. However, placido disk topography revealed greater regularity of the central cornea in the gel-treated group compared to the saline group. The gel-treated group exhibited a lower degree of epithelial hyperplasia than the saline group. Immunohistochemical and gene expression analysis showed that the gel-treated corneas exhibited lower alpha-SMA expression compared with the saline group. CD163 and CD44 were found to be elevated in the saline-treated group compared with normal corneas. CONCLUSIONS: The in situ-forming collagen-PEG gel promoted epithelialization that improved central corneal topography, epithelial layer morphology, and reduced expression of fibrotic and inflammatory biomarkers after 60 days compared to the saline group.
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Lesões da Córnea , Hidrogéis , Animais , Polietilenoglicóis , Seguimentos , Colágeno/metabolismo , Córnea/metabolismoRESUMO
OBJECTIVES: To evaluate primarily the relationship between postoperative complications and hospital costs, and secondarily the relationship between postoperative complications and mortality, following radical cystectomy. METHODS: Postoperative complications were retrospectively examined for 147 patients undergoing radical cystectomy at a university hospital between January 2012 and July 2021. Complications were defined and graded using the Clavien-Dindo classification system. In-hospital cost was calculated using an activity-based costing methodology. Regression modelling was used to investigate the relationships among a priori selected perioperative variables, complications, and costs. The effect of complications on postoperative mortality was ascertained using time-dependent coefficients in a Cox proportional hazards regression model. RESULTS: 135 (92%) patients experienced one or more postoperative complications. The medians of hospital cost for patients who experienced no complications and those who experienced complications were $42,796.3 (29,222.9-53,532.5) and $81,050.1 (49,614.8-122,533.6) respectively, p < 0.001. Hospital costs were strongly associated with complication severity: Clavien-Dindo grade II complications increased costs by 45.2% (p < 0.001, 95% CI 19.1%-76.6%), and Clavien-Dindo grade III to V complications increased costs by 107.5% (p < 0.001, 95% CI 52.4%-181.8%). Each additional count of complication and increase in Clavien-Dindo complication grade increased the risk of mortality 1.28-fold (RR = 1.28, p = 0.006, 95% CI 1.08-1.53) and 2.50-fold (RR = 2.50, p = 0.012 95% CI 1.23-5.07) respectively. CONCLUSIONS: These findings demonstrate a high prevalence of complications following cystectomy and significant associated increases in hospital costs and mortality. Postoperative complications are a key target for cost-containment strategies. TRIAL REGISTRATION: Trial Registration: Australian New Zealand Clinical Trials Registry (ACTRN:12622000057785.
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Cistectomia , Neoplasias da Bexiga Urinária , Humanos , Cistectomia/métodos , Estudos Retrospectivos , Custos Hospitalares , Austrália , Complicações Pós-Operatórias/etiologia , Neoplasias da Bexiga Urinária/cirurgiaRESUMO
Background: Motion Sickness increases risk of performance deficits and safety of flight concerns. The etiology of motion sickness is poorly understood. Here, we attempted to quantify the physiological effects of motion sickness on static balance and determine the genetic predictors associated with these effects. Methods: 16 subjects underwent a disorientation stimulus to induce motion sickness. Motion sickness susceptibility was identified using the Motion Sickness Susceptibility Questionnaire. Postural balance outcomes were measured using two tasks, and small ribonucleic acid profiles were assessed with blood draws before motion sickness stimulus. Differences in postural sway before and after the stimulus as well as effect modification of susceptibility were assessed. A random forest followed by regression tree analysis was constructed for each postural sway variable to determine top genetic and covariate predictors. Findings: Significant differences existed in mean postural balance responses between before and after stimulus. Individuals with longer stimulus survival experienced a greater (but insignificant) perception of sway, even if not displaying increased sway for all conditions. Circulation small ribonucleic acids were differentially expressed between individuals with long and short stimulus survival, many of these microRNA have purported targets in genes related to vestibular disorders. Interpretation: We found motion sickness produces transient motor dysfunction in a healthy military population. Small ribonucleic acids were differentially expressed between subjects with long and short stimulus survival times.
RESUMO
OBJECTIVE: Transthoracic esophagectomy is associated with significant morbidity and mortality. Therefore, it is imperative to optimize perioperative management and minimize complications. In this retrospective analysis, we evaluated the association between fluid balance and esophagectomy complications at a tertiary hospital in Melbourne, Australia, with a particular focus on respiratory morbidity and anastomotic leaks. Cumulative fluid balance was calculated intraoperatively, postoperatively in recovery postoperative day (POD) 0, and on POD 1 and 2. High and low fluid balance was defined as greater than or less than the median fluid balance, respectively, and postoperative surgical complications were graded using the Clavien-Dindo classification. RESULTS: In total, 109 patients, with an average age of 64 years, were included in this study. High fluid balance on POD 0, POD1 and POD 2 was associated with a higher incidence of anastomotic leak (OR 8.59; 95%CI: 2.64-39.0). High fluid balance on POD 2 was associated with more severe complications (of any type) (OR 3.33; 95%CI: 1.4-8.26) and severe pulmonary complications (OR 3.04; 95%CI: 1.27-7.67). For every 1 L extra cumulative fluid balance in POD 1, the odds of a major complication increase by 15%, while controlling for body mass index (BMI) and American Society of Anaesthesiologists (ASA) class. The results show that higher cumulative fluid balance is associated with worsening postoperative outcomes in patients undergoing transthoracic esophagectomy. Restricted fluid balance, especially postoperatively, may mitigate the risk of postoperative complications - however prospective trials are required to establish this definitively.
Assuntos
Neoplasias Esofágicas , Esofagectomia , Humanos , Pessoa de Meia-Idade , Esofagectomia/efeitos adversos , Esofagectomia/métodos , Estudos Retrospectivos , Estudos Prospectivos , Neoplasias Esofágicas/complicações , Neoplasias Esofágicas/cirurgia , Fístula Anastomótica/cirurgia , Complicações Pós-Operatórias/etiologia , Equilíbrio HidroeletrolíticoRESUMO
The objective of this study was to investigate potential associations between an individual's psychophysical maximum acceptable force (MAF) during pushing tasks and biomechanical tissue loads within the lumbar spine. Ten subjects (eight males, two females) pushed a cart with an unknown weight at one push every two minute for a distance of 3.9 m. Two independent variables were investigated, cart control and handle orientation while evaluating their association with the MAF. Dependent variables of hand force and tissue loads for each MAF determination and preceding push trial were assessed using a validated, electromyography-assisted biomechanical model that calculated spinal load distribution throughout the lumbar spine. Results showed no association between spinal loads and the MAF. Only hand forces were associated with the MAF. Therefore, MAFs may be dependent upon tactile sensations from the hands, not the loads on the spine and thus may be unrelated to risk of low back injury. Practitioner Summary: Pushing tasks have become common in manual materials handling (MMH) and these tasks impose different tissue loads compared to lifting tasks. Industry has commonly used the psychophysical tables for job assent and decision of MMH tasks. However, due to the biomechanical complexity of pushing tasks, psychophysics may be misinterpreting risk.