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PURPOSE: To develop a computational model of microwave ablation (MWA) with a thermal accelerant gel and apply the model toward interpreting experimental observations in ex vivo bovine and in vivo porcine liver. METHODS: A 3D coupled electromagnetic-heat transfer model was implemented to characterize thermal profiles within ex vivo bovine and in vivo porcine liver tissue during MWA with the HeatSYNC thermal accelerant. Measured temperature dependent dielectric and thermal properties of the HeatSYNC gel were applied within the model. Simulated extents of MWA zones and transient temperature profiles were compared against experimental measurements in ex vivo bovine liver. Model predictions of thermal profiles under in vivo conditions in porcine liver were used to analyze thermal ablations observed in prior experiments in porcine liver in vivo. RESULTS: Measured electrical conductivity of the HeatSYNC gel was â¼83% higher compared to liver at room temperature, with positive linear temperature dependency, indicating increased microwave absorption within HeatSYNC gel compared to tissue. In ex vivo bovine liver, model predicted ablation zone extents of (31.5 × 36) mm with the HeatSYNC, compared to (32.9 ± 2.6 × 40.2 ± 2.3) mm in experiments (volume differences 4 ± 4.1 cm3). Computational models under in vivo conditions in porcine liver suggest approximating the HeatSYNC gel spreading within liver tissue during ablations as a plausible explanation for larger ablation zones observed in prior in vivo studies. CONCLUSION: Computational models of MWA with thermal accelerants provide insight into the impact of accelerant on MWA, and with further development, could predict ablations with a variety of gel injection sites.
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Fígado , Micro-Ondas , Animais , Bovinos , Suínos , Micro-Ondas/uso terapêutico , Fígado/cirurgia , Simulação por Computador , Condutividade Elétrica , Temperatura AltaRESUMO
BACKGROUND: Open-label platform trials and a prospective meta-analysis suggest efficacy of anti-interleukin (IL)-6R therapies in hospitalized patients with coronavirus disease 2019 (COVID-19) receiving corticosteroids. This study evaluated the efficacy and safety of sarilumab, an anti-IL-6R monoclonal antibody, in the treatment of hospitalized patients with COVID-19. METHODS: In this adaptive, phase 2/3, randomized, double-blind, placebo-controlled trial, adults hospitalized with COVID-19 received intravenous sarilumab 400 mg or placebo. The phase 3 primary analysis population included patients with critical COVID-19 receiving mechanical ventilation (MV). The primary outcome was proportion of patients with ≥1-point improvement in clinical status from baseline to day 22. RESULTS: There were 457 and 1365 patients randomized and treated in phases 2 and 3, respectively. In phase 3, patients with critical COVID-19 receiving MV (nâ =â 298; 28.2% on corticosteroids), the proportion with ≥1-point improvement in clinical status (alive, not receiving MV) at day 22 was 43.2% for sarilumab and 35.5% for placebo (risk difference, +7.5%; 95% confidence interval [CI], -7.4 to 21.3; P =.3261), a relative risk improvement of 21.7%. In post hoc analyses pooling phase 2 and 3 critical patients receiving MV, the hazard ratio for death for sarilumab vs placebo was 0.76 (95% CI, .51 to 1.13) overall and 0.49 (95% CI, .25 to .94) in patients receiving corticosteroids at baseline. CONCLUSIONS: This study did not establish the efficacy of sarilumab in hospitalized patients with severe/critical COVID-19. Post hoc analyses were consistent with other studies that found a benefit of sarilumab in patients receiving corticosteroids. CLINICAL TRIALS REGISTRATION: NCT04315298.
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Tratamento Farmacológico da COVID-19 , Adulto , Anticorpos Monoclonais Humanizados , Humanos , Estudos Prospectivos , Resultado do TratamentoRESUMO
BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is associated with sugar-sweetened beverage (SSB) consumption in cross-sectional studies. In a prospective cohort, we examined the association of beverage consumption (SSB and diet soda) with incident NAFLD and changes in hepatic fat in the Framingham Heart Study (FHS). METHODS: We conducted a prospective observational study of participants from the FHS Third Generation and Offspring cohorts who participated in computed tomography sub-studies. Participants were classified according to their average SSB or diet soda consumption, which was derived from baseline and follow-up food frequency questionnaires: non-consumers (0-<1/month), occasional consumers (1/month-<1/week), and frequent consumers (≥1/week-≥1/day). Hepatic fat was quantified by the liver fat attenuation measurements on computed tomography scan. The primary dependent variable was incident NAFLD; secondarily, we investigated change in liver fat. RESULTS: The cohorts included 691 Offspring (mean age, 62.8 ± 8.2 years; 57.7% women) and 945 Third Generation participants (mean age, 48.4 ± 6.3 years; 46.6% women). In the Offspring cohort, there was a dose-response relationship with SSB consumption and incident NAFLD. Frequent SSB consumers had 2.53 times increased odds of incident NAFLD compared with non-consumers (95% confidence interval, 1.36-4.7) after multivariable analysis. For Offspring cohort participants, occasional and frequent consumers of SSB had a more adverse increase in liver fat compared with non-consumers. CONCLUSIONS: Higher average SSB intake is associated with increase in liver fat over 6 years of follow-up and increased odds of incident NAFLD especially among the older cohort, whereas no consistent association was observed for the younger Third Generation cohort.
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Hepatopatia Gordurosa não Alcoólica , Bebidas Adoçadas com Açúcar , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Adulto , Masculino , Bebidas Adoçadas com Açúcar/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Estudos Prospectivos , Estudos Transversais , Estudos Longitudinais , Dieta/efeitos adversosRESUMO
PURPOSE: To determine the effects of a thermal accelerant gel on temperature parameters during microwave liver ablation. MATERIALS AND METHODS: Sixteen consecutive liver ablations were performed in 5 domestic swine under general anesthesia with (n = 8) and without (n = 8) administration of thermal accelerant gel. Ablation zone temperature was assessed by real-time MR thermometry, measured as maximum temperature (Tmax) and the volume of tissue ≥ 60°C (V60). Tissue heating rate, ablation zone shape, and thermal energy deposition using the temperature degree-minutes at 43°C (TDM43) index were also measured. Differences between groups were analyzed using generalized mixed modeling with significance set at P = .05. RESULTS: Mean peak ablation zone temperature was significantly greater with thermal accelerant use (mean Tmax, thermal accelerant: 120.0°C, 95% confidence interval [CI] 113.0°C-126.9°C; mean Tmax, control: 80.3°C, 95% CI 72.7°C-88.0°C; P < .001), and a significantly larger volume of liver tissue achieved or exceeded 60°C when thermal accelerant was administered (mean V60, thermal accelerant: 22.2 cm3; mean V60, control: 15.9 cm3; P < .001). Significantly greater thermal energy deposition was observed during ablations performed with accelerant (mean TDM43, thermal accelerant: 198.4 min, 95% CI 170.7-230.6 min; mean TDM43, control: 82.8 min, 95% CI 80.5-85.1 min; P < .0001). The rate of tissue heating was significantly greater with thermal accelerant use (thermal accelerant: 5.8 min ± 0.4; control: 10.0 min; P < .001), and accelerant gel ablations demonstrated a more spherical temperature distribution (P = .002). CONCLUSIONS: Thermal accelerant use is associated with higher microwave ablation zone temperatures, greater thermal energy deposition, and faster and more spherical tissue heating compared with control ablations.
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Técnicas de Ablação , Temperatura Alta , Fígado/cirurgia , Imageamento por Ressonância Magnética , Micro-Ondas , Polímeros Responsivos a Estímulos/administração & dosagem , Cirurgia Assistida por Computador , Termometria , Animais , Géis , Fígado/diagnóstico por imagem , Masculino , Modelos Animais , Sus scrofaRESUMO
Background Thermal ablation of cancers may be associated with high rates of local tumor progression. A thermal accelerant gel has been developed to improve the transmission of microwave energy in biologic tissues with the aim of enlarging the thermal ablation zone. Purpose To determine the effects of a thermal accelerant gel on microwave ablation zone volumes in porcine lung and to compare percutaneous and endobronchial delivery methods. Materials and Methods Thirty-two consecutive microwave lung ablations were performed in nine 12-week-old domestic male swine under general anesthesia by using fluoroscopic guidance between September 2017 and April 2018. Experimental ablations were performed following percutaneous injection of thermal accelerant into the lung (n = 16) or after endobronchial injection by using a flexible bronchoscope (n = 8). Control ablations were performed without accelerant gel (n = 8). Lung tissue was explanted after the animals were killed, and ablation zone volumes were calculated as the primary outcome measure by using triphenyltetrazolium chloride vital staining. Differences in treatment volumes were analyzed by generalized mixed modeling. Results Thermal accelerant ablation zone volumes were larger than control ablations (accelerant vs control ablation, 4.3 cm3 [95% confidence interval: 3.4, 5.5] vs 2.1 cm3 [95% confidence interval: 1.4, 2.9], respectively; P < .001). Among ablations with the thermal accelerant, those performed following percutaneous injection had a larger average ablation zone volume than those performed following endobronchial injection (percutaneous vs endobronchial, 4.8 cm3 [95% confidence interval: 3.6, 6.4] vs 3.3 cm3 [95% confidence interval: 2.9, 3.8], respectively; P = .03). Ablation zones created after endobronchial gel injection were more uniform in size distribution (standard error, percutaneous vs endobronchial: 0.13 vs 0.07, respectively; P = .03). Conclusion Use of thermal accelerant results in larger microwave ablation zone volumes in normal porcine lung tissue. Percutaneous thermal accelerant injection leads to a larger ablation zone volume compared with endobronchial injection, whereas a more homogeneous and precise ablation zone size is observed by using the endobronchial approach. © RSNA, 2019 See also the editorial by Goldberg in this issue.
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Técnicas de Ablação/métodos , Géis/administração & dosagem , Hipertermia Induzida/métodos , Pulmão/diagnóstico por imagem , Administração Cutânea , Administração por Inalação , Animais , Meios de Contraste/administração & dosagem , Meios de Contraste/química , Fluoroscopia/métodos , Géis/química , Pulmão/cirurgia , Masculino , Micro-Ondas , Cirurgia Assistida por Computador , Sus scrofa , SuínosRESUMO
PURPOSE OF REVIEW: The assessment and management of perioperative pain in an intensive care setting is complex and challenging, requiring several patient-specific considerations. Administering analgesia is difficult due to interacting effects of pre-existing conditions, interventions, and deviation from standard levels of expressiveness of pain. A significant part of this complexity also arises from the reduced capacity of critically ill patients to fully communicate the severity and nature of their pain. We provide an overview of pharmacological approaches and regional techniques, which can be employed alongside the management of anxiety and sleep, to alleviate pain in the critically ill patients in the perioperative period. These interventions require additional assessments unique to critical care, yet achieving pain relief for improving clinical outcomes and patient satisfaction remains a constant. RECENT FINDINGS: The latest research has found that the development of standardized mechanisms and protocols to optimize the diagnosis, assessment, and management of pain in the critically ill can provide the best outcomes. The numerical rating scale, critical care pain observation criteria, and behavior pain scale has shown higher reliability to accurately assess pain in the critically ill. Most importantly, preemptive analgesia and the emphasis on early pain control-in the perioperative setting, ICU, and post-discharge-are crucial in minimizing chronic post-discharge pain. Finally, the multimodal approach is still found to be the most effective. This includes pharmacological treatments, regional nerve block, and epidural techniques, as well as alternative methods that are cheap, safe, and easily available. All these together have shown to help control pain, provide psychological support, and prevent long-term co-morbidities in the critically ill. Largely, pain in the critically ill patient is still a very complex issue that requires appropriate diagnosis, assessment, and management of the pain itself and treating all the underlying co-morbidities as well. Many different factors makes it challenging, especially the difficulty in communicating with an ICU patient. However, by looking at the patient as a whole, treating pain early with the multimodal approach, there seems to be some promising results in improving outcomes. It has shown that the improved outcomes in critically ill patients in the perioperative period seen with optimized pain management and ICU can shorten hospital stays, decreased inpatient costs, and limit the use of limited resources.
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Cuidados Críticos , Estado Terminal/reabilitação , Manejo da Dor , Medição da Dor , Dor/tratamento farmacológico , Analgésicos/uso terapêutico , HumanosRESUMO
OBJECTIVES: To investigate the effects of a novel caesium-based thermal accelerant (TA) agent on ablation zone volumes following in vivo microwave ablation of porcine liver and skeletal muscle, and to correlate the effects of TA with target organ perfusion. MATERIALS AND METHODS: This prospective study was performed following institutional animal care and use committee approval. Microwave ablation was performed in liver and resting skeletal muscle in eight Sus scrofa domesticus swine following administration of TA at concentrations of 0 mg/mL (control), 100 mg/mL and 250 mg/mL. Treated tissues were explanted and stained with triphenyltetrazolium chloride (TTC) for quantification of ablation zone volumes, which were compared between TA and control conditions. Hematoxylin and eosin (H&E) staining was also performed for histologic analysis. General mixed modelling with a log-normal distribution was used for all quantitative comparisons (p = 0.05). RESULTS: A total of 28 ablations were performed in the liver and 18 in the skeletal muscle. The use of TA significantly increased ablation zone volumes in a dose-dependent manner in both the porcine muscle and liver (p < 0.01). Both the absolute mean ablation zone volume and percentage increase in ablation zone volume were greater in the resting skeletal muscle than in the liver. In one swine, a qualitative mitigation of heat sink effects was observed by TTC and H&E staining. Non-lethal polymorphic ventricular tachycardia was identified in one swine, treated with intravenous amiodarone. CONCLUSIONS: The use of a novel TA agent significantly increased mean ablation zone volumes following microwave ablation using a porcine model. The relationship between TA administration and ablation size was dose-dependent and inversely proportional to the degree of target organ perfusion, and a qualitative reduction in heat-sink effects was observed.
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Ablação por Cateter/métodos , Micro-Ondas , Radioterapia Guiada por Imagem/métodos , Animais , Masculino , Modelos Animais , SuínosRESUMO
Background: For most patients with hypertrophic cardiomyopathy (HCM), the clinical course is considered relatively benign, similar to hypertensive heart disease (HHD). We compared the long-term outcomes in patients with HCM versus HHD from a large healthcare system database. Methods: Data from SSM Virtual Data Warehouse were used to identify patients with a new diagnosis of either HCM or HHD who followed up in our system for at least 6 months. HCM patients were matched 1:1 to HHD patients based on age, sex, and race. Outcomes examined included heart failure (HF) admission, ventricular tachyarrhythmia (ventricular fibrillation or sustained ventricular tachycardia), and need for pacemaker or defibrillator implantation. We identified 1904 HCM patients along with HHD controls. Results: After adjusting for demographic characteristics and relevant comorbidities, HCM had higher odds of HF admission (odds ratio [OR]: 1.73, 95% confidence interval [CI]: 1.43-2.10), ventricular tachyarrhythmias (OR: 2.31, CI: 1.60-3.33), pacemaker implantation (OR: 2.14, CI: 1.29-3.57), and defibrillator implantation (OR: 3.77, CI: 1.82-7.83). Survival analysis confirmed the difference in outcomes early on from the time of diagnosis. Conclusion: In this retrospective study from a large healthcare system database, HCM patients had significantly higher incidences of HF admission, ventricular tachyarrhythmias, and pacemaker or defibrillator implantation compared to HHD patients.
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Objective: The assessment of primary aldosteronism incorporates adrenal vein sampling (AVS) to lateralize aldosterone excess. Current adrenal vein sampling protocols rely on concurrent cortisol measurements to assess successful cannulation and lateralization and may be inaccurate in the setting of autonomous cortisol secretion. We aimed to compare the measurement of plasma cortisol and metanephrine concentrations to assess cannulation and lateralization during AVS. Design: This is a diagnostic accuracy study in a tertiary referral endocrinology department. Methods: Forty-one consecutive patients with confirmed primary aldosteronism undergoing AVS (49 procedures) were included. None had cortisol autonomy. The use of plasma metanephrine-based ratios were compared with standard cortisol-based ratios to assess cannulation and lateralization during ACTH-stimulated AVS. Results: There was strong agreement between a cortisol selectivity index (SI) ≥5.0 and an adrenal vein (AV) to peripheral vein (PV) plasma metanephrine ratio (AVmet-PVmet) of ≥12.0 to indicate successful cannulation of the AV (n = 117, sensitivity 98%, specificity 89%, positive predictive value (PPV) 95%, negative predictive value (NPV) 94%). There was strong agreement between the standard cortisol-based SI and an AV plasma metanephrine-to-normetanephrine ratio (AVmet-AVnormet) of ≥2.0 to indicate successful cannulation (n = 117, sensitivity 93%, specificity 86%, PPV 94%, NPV 84%). There was strong agreement between the cortisol- or metanephrine-derived lateralization index (LI) > 4.0 for determining lateralization (n = 26, sensitivity 100%, specificity 94.1%, PPV 91.6%, NPV 100%). Conclusions: Ratios incorporating plasma metanephrines provide comparable outcomes to standard cortisol-based measurements for interpretation of AVS. Further studies are required to assess the use of metanephrine-derived ratios in the context of confirmed cortisol autonomy. Significance statement: Primary aldosteronism is a common cause of secondary hypertension, and adrenal vein sampling remains the gold standard test to assess lateralization. Cortisol-derived ratios to assess cannulation and lateralization may be affected by concurrent cortisol dysfunction, which is not uncommon in the context of primary aldosteronism. Our study showed comparable outcomes when using accepted cortisol-derived or metanephrine-derived ratios to determine cannulation and lateralization during adrenal vein sampling. Further research is required to validate these findings and to assess the use of metanephrine-derived ratios in the context of confirmed concurrent cortisol dysfunction.
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Influenza virus nucleoprotein (NP) is one of the most conserved influenza proteins. Both NP antigen and anti-NP antibodies are used as reagents in influenza diagnostic kits, with applications in both clinical practice, and influenza zoonotic surveillance programs. Despite this, studies on the biochemical basis of NP diagnostic serology and NP epitopes are not as developed as for hemagglutinin (HA), the fast-evolving antigen which has been the critical component of current influenza vaccines. Here, we characterized the NP serology of mice, ferret, and human sera and the immunogenic effects of NP antigen presented as different structural complexes. Furthermore, we show that a classical anti-NP mouse mAb HB65 could detect NP in some commercial influenza vaccines. MAb HB65 bound a linear epitope with nanomolar affinity. Our analysis suggests that linear NP epitopes paired with their corresponding characterized detection antibodies could aid in designing and improving diagnostic technologies for influenza virus.
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Development of intranasal vaccines for respiratory viruses has gained popularity. However, currently only a live-attenuated influenza vaccine is FDA-approved for intranasal administration. Here, we focused on influenza virus as it circulates seasonally, has pandemic potential, and has vaccine formulations that present hemagglutinin (HA) in different structural arrangements. These display differences have not been correlated with induction of pan-H1 antibodies or shown to provide intranasal protection. Using electron microscopy, biochemistry and animal studies, we identified HA complexes arranged as lipid discs with multiple trimeric HAs displayed along the perimeter, termed spike nanobicelles (SNB). We utilized a structure-guided approach to synthesize in vitro assembled spiked nanobicelles (IA-SNB) from a classical 1934 H1N1 influenza virus. IA-SNBs elicited pan-H1 antibodies and provided protection against antigenically divergent H1N1 viruses via intranasal immunizations. Viral glycoprotein spikes displayed as SNBs could aid in combating antigenic variation and provide innovative intranasal vaccines to aid universal influenza vaccine development.
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Adult T cell leukemia (ATL), caused by infection with human T cell leukemia virus type 1 (HTLV-1), is often complicated by hypercalcemia and osteolytic lesions. Therefore, we studied the communication between patient-derived ATL cells (ATL-PDX) and HTLV-1 immortalized CD4+ T cell lines (HTLV/T) with osteoclasts and their effects on bone mass in mice. Intratibial inoculation of some HTLV/T lead to a profound local decrease in bone mass similar to marrow-replacing ATL-PDX, despite the fact that few HTLV/T cells persisted in the bone. To study the direct effect of HTLV/T and ATL-PDX on osteoclasts, supernatants were added to murine and human osteoclast precursors. ATL-PDX supernatants from hypercalcemic patients promoted formation of mature osteoclasts, while those from HTLV/T were variably stimulatory, but had largely consistent effects between human and murine cultures. Interestingly, this osteoclastic activity did not correlate with expression of osteoclastogenic cytokine RANKL, suggesting an alternative mechanism. HTLV/T and ATL-PDX produce small extracellular vesicles (sEV), known to facilitate HTLV-1 infection. We hypothesized that these sEV also mediate bone loss by targeting osteoclasts. We isolated sEV from both HTLV/T and ATL-PDX, and found they carried most of the activity found in supernatants. In contrast, sEV from uninfected activated T cells had little effect. Analysis of sEV (both active and inactive) by mass spectrometry and electron microscopy confirmed absence of RANKL and intact virus. Viral proteins Tax and Env were only present in sEV from the active, osteoclast-stimulatory group, along with increased representation of proteins involved in osteoclastogenesis and bone resorption. sEV injected over mouse calvaria in the presence of low dose RANKL caused more osteolysis than RANKL alone. Thus, HTLV-1 infection of T cells can cause release of sEV with strong osteolytic potential, providing a mechanism beyond RANKL production that modifies the bone microenvironment, even in the absence of overt leukemia.
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Adult T cell leukaemia (ATL), caused by infection with human T- lymphotropic virus type 1 (HTLV-1), is often complicated by hypercalcemia and osteolytic lesions. Therefore, we studied the communication between patient-derived ATL cells (ATL-PDX) and HTLV-1 immortalized CD4+ T cell lines (HTLV/T) with osteoclasts and their effects on bone mass in mice. Intratibial inoculation of some HTLV/T leads to a profound local decrease in bone mass similar to marrow-replacing ATL-PDX, despite the fact that few HTLV/T cells persisted in the bone. To study the direct effect of HTLV/T and ATL-PDX on osteoclasts, supernatants were added to murine and human osteoclast precursors. ATL-PDX supernatants from hypercalcemic patients promoted the formation of mature osteoclasts, while those from HTLV/T were variably stimulatory, but had largely consistent effects between human and murine cultures. Interestingly, this osteoclastic activity did not correlate with expression of osteoclastogenic cytokine receptor activator of nuclear factor kappa-B ligand (RANKL), suggesting an alternative mechanism. HTLV/T and ATL-PDX produce small extracellular vesicles (sEV), known to facilitate HTLV-1 infection. We hypothesized that these sEV also mediate bone loss by targeting osteoclasts. We isolated sEV from both HTLV/T and ATL-PDX, and found they carried most of the activity found in supernatants. In contrast, sEV from uninfected activated T cells had little effect. Analysis of sEV (both active and inactive) by mass spectrometry and electron microscopy confirmed absence of RANKL and intact virus. Viral proteins Tax and Env were only present in sEV from the active, osteoclast-stimulatory group, along with increased representation of proteins involved in osteoclastogenesis and bone resorption. sEV from osteoclast-active HTLV/T injected over mouse calvaria in the presence of low-dose RANKL caused more osteolysis than osteoclast-inactive sEV or RANKL alone. Thus, HTLV-1 infection of T cells can cause release of sEV with strong osteolytic potential, providing a mechanism beyond RANKL production that modifies the bone microenvironment, even in the absence of overt leukaemia.
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Vesículas Extracelulares , Vírus Linfotrópico T Tipo 1 Humano , Osteoclastos , Humanos , Animais , Vesículas Extracelulares/metabolismo , Osteoclastos/metabolismo , Osteoclastos/virologia , Camundongos , Ligante RANK/metabolismo , Leucemia-Linfoma de Células T do Adulto/metabolismo , Leucemia-Linfoma de Células T do Adulto/virologia , Leucemia-Linfoma de Células T do Adulto/patologia , Reabsorção Óssea/metabolismo , Reabsorção Óssea/virologia , Infecções por HTLV-I/metabolismo , Infecções por HTLV-I/complicações , Infecções por HTLV-I/virologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/imunologiaRESUMO
This paper presents a novel positioning feedback sensor using a pair of Hall effect elements on a long-range flexure stage. The proposed Hall effect positioning feedback sensor eliminates error and uncertainty by measuring the center of the flexure stage, where a machine tool or measurement probes would take place in the industrial application. A pair of Hall effect elements were amplified in a differential configuration as the cylindrical permanent magnet enclosed in the center of the shuttle in the flexure stage that moves back and forth, generating a uniform gradient magnetic flux intensity. Nonlinear magnetic flux characteristics of a single Hall effect element were eliminated, and high-quality sensor sensitivity was achieved by differential amplification of the two Hall effect elements. The magnetic field analysis to characterize the linearity of the proposed displacement sensor was simulated using the finite element method to prove that the non-linearity of a single hall effect element may be mitigated by employing the differential amplification technique. The flexure stage was additively manufactured into a monolithic structure, and the permanent magnet was fitted into the shuttle of the flexure stage. Each Hall effect element was placed on either side of the magnet at a certain distance on the axis of shuttle movement. The proposed sensor was characterized by performing dynamic system identification of the flexure stage: open-loop response and closed-loop response. The Laser Displacement Sensor (LDS) with the 10 nm resolution was used for baseline comparison and datum line with respect to the proposed sensor. The proposed sensor responses agreed well with LDS in various dynamic inputs. The sensor response was analyzed with two differential amplification signal processing techniques. The maximum sensitivity of the two signal processing techniques was determined to be 16.55 mV/µm, and the resolution was observed as 2.5 µm. In sum, the differentially amplified Hall effect displacement sensor achieved positioning feedback with high sensitivity and linearity and minimized the sensor placement error while maintaining low cost and simple configuration.
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Lasers , Campos MagnéticosRESUMO
AIM: To describe the frequency and characteristics of patients referred for specialist investigation of primary aldosteronism (PA) in the lower North Island over a 5-year period, and the outcomes of those who received treatment. METHODS: Patients who underwent confirmatory testing or treatment for PA at Wellington Regional Hospital were retrospectively identified and data were collected from electronic clinical records. RESULTS: There has been a five-fold increase in both referrals and confirmatory testing for PA in 2021 compared to 2015. Compared to patients without PA, those eventually diagnosed with PA had a higher ARR, serum sodium, antihypertensive requirement and cardiovascular disease prevalence, as well as lower serum renin, potassium and GFR (all p <0.05), but similar blood pressure. Complete or partial clinical success was achieved in 96% of surgically treated patients compared with 70% of medically treated patients. Thirty-nine percent of patients experienced minor adverse effects with spironolactone and only one significant adverse event was experienced perioperatively. CONCLUSIONS: The rate of referrals and confirmatory testing for PA are increasing in our region. Adrenalectomy and mineralocorticoid antagonist therapy are both safe and effective treatments, although minor adverse effects were common with spironolactone.
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Hiperaldosteronismo , Hipertensão , Humanos , Espironolactona/uso terapêutico , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/epidemiologia , Hiperaldosteronismo/terapia , Estudos Retrospectivos , Nova Zelândia/epidemiologia , Hipertensão/epidemiologia , Adrenalectomia , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Renina/uso terapêutico , Encaminhamento e Consulta , Aldosterona/uso terapêuticoRESUMO
Irritable Bowel Syndrome (IBS) is a functional disorder of the gastrointestinal tract characterized by abdominal pain and altered bowel habits. It has a prevalence of 10 to 25% in the United States and has a high disease burden, as evidenced by reduced quality of life, decreased work productivity and increased healthcare utilization and costs. IBS has been associated with several intra-intestinal and extra-intestinal conditions, including psychiatric comorbidities. Although the pathophysiology of IBS has not been fully elucidated, it involves dysregulation of communication between the brain and gut (brain-gut axis) which is associated with alterations in intestinal motility, gut permeability, visceral hypersensitivity and gut microbiota composition. The purpose of this article is to review the role the gut microbiota plays in the pathophysiology of IBS, understand factors that affect the gut microbiome and explore the microbiome as a target of treatment.
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Anellovirus (AV) is a ubiquitous virus in the human population. Individuals can be infected with multiple AV genera and species to form a heterogeneous repertoire, termed the anellome. Using advanced methods, we examined the anellomes from 12 paired serum and liver samples, as well as 2701 subjects with different clinical diagnoses. Overall, anellomes are remarkably individualized, with significant among-group differences (Kruskal-Wallis test p = 6.6 × 10-162 for richness and p = 7.48 × 10-162 for Shannon entropy). High dissimilarity scores (beta diversity) were observed between patient groups, except for paired serum and liver samples. At the population level, the relative abundance of combinational AV genus Betatorquevirus (torque teno mini viruses, TTMV), and Gammatorquevirus (torque teno midi viruses, TTMDV) exhibited an exponential distribution with a low bound point at 32%. Defined by this value, the AV TTMV/TTMDV-expanded anellome was significantly enriched among patients with acute liver failure (31.7%) and liver transplantation (40.7%), compared with other patient groups (χ2 test: p = 4.1 × 10-8-3.2 × 10-3). Therefore, anellome heterogeneity may be predictive of clinical outcomes in certain diseases, such as liver disease. The consistency of anellome between paired serum and liver samples indicates that a liquid biopsy approach would be suitable for longitudinal studies to clarify the causality of the AV TTMV/TTMDV-expanded anellome in the outcomes of liver disease.
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Anelloviridae , Falência Hepática Aguda , Transplante de Fígado , Humanos , Anelloviridae/genética , PenicilinasRESUMO
BACKGROUND: Molnupiravir is an oral prodrug of ß-D-N4-hydroxycytidine, active against SARS-CoV-2 in vitro and in animal models. We report data from the phase 2 component of MOVe-IN, a clinical trial evaluating molnupiravir in patients hospitalized with Covid-19. METHODS: We conducted a randomized, placebo-controlled, double-blind phase 2/3 trial in patients 18 years old and older requiring in-hospital treatment for laboratory-confirmed Covid-19 with symptom onset 10 or fewer days before randomization. Participants were randomly assigned to placebo or molnupiravir 200 mg, 400 mg, or 800 mg (1:1:1:1 ratio), twice daily for 5 days. Primary end points were safety and sustained recovery (participant alive and either not hospitalized or medically ready for discharge) through day 29. RESULTS: Of 304 randomly assigned participants, 218 received at least one dose of molnupiravir and 75 of placebo. At baseline, 74.0% had at least one risk factor for severe Covid-19. Adverse events were reported in 121 of 218 (55.5%) molnupiravir-treated and 46 of 75 (61.3%) placebo-treated participants, with no apparent dose effect on adverse event rates and no evidence of hematologic toxicity based on prespecified adverse events. Of 16 confirmed deaths, most were in participants with severe Covid-19 (75.0%), with underlying comorbidities (87.5%), older than 60 years of age (81.3%), and/or symptom duration longer than 5 days (75.0%) at randomization. Median time to sustained recovery was 9 days in all groups, with similar day 29 recovery rates ranging from 81.5% to 85.2%. CONCLUSIONS: In this phase 2 trial of patients hospitalized with Covid-19, a 5-day course of molnupiravir up to 800 mg twice daily was not associated with dose-limiting side effects or adverse events, but did not demonstrate clinical benefit. (Funded by Merck Sharp & Dohme; ClinicalTrials.gov NCT04575584.)
Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Citidina , Hospitalização , Hidroxilaminas , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Citidina/análogos & derivados , Citidina/uso terapêutico , Método Duplo-Cego , Hidroxilaminas/uso terapêutico , Antivirais/uso terapêutico , Antivirais/efeitos adversos , Antivirais/administração & dosagem , Idoso , Hospitalização/estatística & dados numéricos , Adulto , COVID-19 , SARS-CoV-2 , Resultado do TratamentoRESUMO
Peripheral venous access is perhaps the most commonly performed procedure in hospitals, urgent care, or surgical centers across the country. The ability to obtain peripheral intravenous (IV) access, and in a timely manner, is arguably one of the most important skill sets to be mastered by health care professionals. While skill and experience play a role in successful and timely vascular access, numerous patient factors such as obesity, diabetes, IV drug use, and chronic kidney disease may pose unique challenges to even the most skilled health care professional. In patients with difficult access, there are often multiple attempts, which can be both time consuming for the provider and painful for the patients. Direct visualization of blood vessels using ultrasonography has an advantage over the standard landmark technique and can improve the success rate of peripheral IV or arterial line placement in this patient population. Given the success of ultrasound guidance with access placement, it is imperative that all health care profesionals become proficient with this technique. The aim of this review article is to provide concise and practical information on the basics of ultrasound and its application to obtain peripheral venous and arterial access.