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2.
Ann Vasc Surg ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964443

RESUMO

OBJECTIVE: To present the value of intravascular ultrasound (IVUS) in diagnosis and treatment of complicated type B aortic dissection (TBD) with malperfusion (MP). Especially the value of IVUS regarding the treatment strategy, reoperation rate, acute kidney injury (AKI) and false lumen thrombosis (FLT) was investigated. METHODS: Retrospective analysis of 25 TBD cases with MP treated with endovascular therapy from April 2019 to August 2022. In 17 cases angiography & IVUS were applied during the operation (IVUS group) and in 8 cases angiography was used without IVUS (control group) for final intraoperative control. IVUS was used to assess the true lumen collapse and to decide if additional bare stenting was necessary or not. Details from patients' charts and documentation from surgeries were analyzed. The endovascular technique included thoracic endovascular aortic repair (TEVAR) with primary entry sealing and -if needed- bare stenting of the true lumen distal of the entry tears using the PETTICOAT (Provisional Extension To Induce Complete Attachment) technique. RESULTS: All patients presented with pain localized mostly (48%) in thorax and abdomen. In all patients the proximal entry tear of the dissection was covered using TEVAR. The PETTICOAT technique was applied in 13 cases (52%), whereas most combined procedures were applied in the IVUS group (12 compared to 1; p=0,02). A total of 3 patients (1 in the control group; 12,5% and 2 in the IVUS group; 11,8%) underwent a bowel resection. Totally 8 patients (32%) underwent a reoperation in aorta (3 during the hospital stay). There were no statistical differences between IVUS and control group regarding the preoperative findings, the reoperation rates and the postoperative complications. 5 patients died (4 during the hospital stay), 1 in control and 4 in IVUS group; p=0,53. The follow up included a clinical and a computed tomography angiography (CTA) examination. No statistically significant difference regarding occurrence and extension of FLT was observed between the two groups. CONCLUSIONS: The IVUS and control groups showed no difference in survival rates. The use of IVUS extended the indication for PETTICOAT technique with statistically significant difference. A milder form of AKI presented in the IVUS group compared to the control group. In addition, a stronger correlation between IVUS and the avoidance of an aorta reoperation was observed, though it did not reach statistical significance.

3.
Sci Rep ; 14(1): 15278, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961162

RESUMO

To determine the diagnostic yield of cone beam computed tomography (CBCT) compared with 3 T magnetic resonance imaging (MRI) for the evaluation of subchondral insufficiency fractures of the knee. Consecutive patients with subchondral insufficiency fractures of the knee examined by 3 T MRI and CBCT of the femoral condyles were reviewed. Two experienced raters graded the lesion severity on 3 T MRI and CBCT images: grade 1: no signs of a subchondral bone lesion; grade 2: subchondral trabecular fracture or cystic changes, but without infraction of the subchondral bone plate; grade 3: collapse of the subchondral bone plate. Ratings were repeated after six weeks to determine reliability. In addition, the bone lesion size was measured as elliptical area (mm2) and compared between CBCT and T1-weighted MRI sequences. Among 30 patients included (43.3% women; mean age: 60.9 ± 12.8 years; body mass index (BMI) 29.0 ± 12.8 kg/m2), the medial femoral condyle was affected in 21/30 patients (70%). The grading of subchondral lesions between MRI and CBCT did not match in 12 cases (40%). Based on MRI images, an underestimation (i.e., undergrading) compared with CBCT was observed in nine cases (30%), whereas overgrading occurred in three cases (10%). Compared to CBCT, routine T1-weighted 3 T sequences significantly overestimated osseus defect zones in sagittal (84.7 ± 68.9 mm2 vs. 35.9 ± 38.2 mm2, p < 0.01, Cohen's d = 1.14) and coronal orientation (53.1 ± 24.0 mm2 vs. 22.0 ± 15.2 mm2, p < 0.01, Cohen's d = 1.23). The reproducibility of the grading determined by intra- and inter-rater agreement was very high in MRI (intra-class correlation coefficient (ICC) 0.78 and 0.90, respectively) and CBCT (ICC 0.96 and 0.96, respectively). In patients with subchondral insufficiency fractures of the knee, the use of CBCT revealed discrepancies in lesion grading compared with MRI. These findings are clinically relevant, as precise determination of subchondral bone plate integrity may influence the decision about conservative or surgical treatment. CBCT represents our imaging modality of choice for grading the lesion and assessing subchondral bone plate integrity. MRI remains the gold standard modality to detect especially early stages.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Imageamento por Ressonância Magnética , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Feminino , Masculino , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Idoso , Fraturas de Estresse/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/patologia , Reprodutibilidade dos Testes
4.
Arch Bone Jt Surg ; 12(6): 407-411, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38919746

RESUMO

Objectives: To assess fracture union rates using novel intramedullary plate technique. Post-operative humeral neck-shaft angles, patient range of motion and complication profile were secondary outcomes of interest. Methods: Single surgeon, retrospective case series of surgical technique at major trauma centre in Scotland. A 2.0mm mini-fragment plate was secured to the humeral head to act as an intramedullary strut during fixation in complex proximal humerus fractures. Fracture union and neck-shaft angle were assessed radiologically, whilst range of motion and complication profiles were assessed clinically. Results: Twelve patients were followed up for an average of 10 months post-operatively. All achieved bony union with a mean neck-shaft angle of 128°. Mean range of motion values were 100° forward elevation, 83° abduction, 60° internal rotation and 37° external rotation. Four patients required further surgical intervention- two for hardware prominence, one for adhesive capsulitis and one for subsequent rotator cuff failure. There were no cases of avascular necrosis or infection. Conclusion: This novel technique addresses the established biomechanical propensity of proximal humerus fractures to fail in varus collapse and screw cut-out. This method provides an alternative to arthroplasty in the most severe proximal humerus fractures and is readily adopted via standard orthopaedic kit.

5.
Future Sci OA ; 10(1): FSO941, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841180

RESUMO

Aim: Venous air embolism is a rare but potentially life threatening complication of endoscopic retrograde cholangiopancreatography. Diagnosis is difficult because of the lack of specific signs or symptoms. Case: A 62-year-old man underwent endoscopic retrograde cholangiopancreatography for choledocholithiasis. A cardiovascular collapse occurred during the procedure. The echocardiography showed air within the right ventricle. Aspiration of air from the right ventricle was done and saved the patient's life. Conclusion: We highlight through this case that increased awareness is essential for prompt recognition of the air embolism to allow life-saving therapy.


Endoscopic treatment is the first-line treatment for biliary stones. It may be associated with various complications. We report the case of a 62-year-old patient who underwent endoscopic treatment for biliary stone. During the procedure, he experienced disturbed cardiac function due to the passage of air bubbles into the cardiac cavities. The bubbles were aspirated with a good outcome.

6.
Materials (Basel) ; 17(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38893914

RESUMO

Several overloaded-induced overturning incidents of girder bridges with single-column piers have occurred in recent years, resulting in significant casualties and economic losses. Temperature, in addition to overloading, may also play a role in exacerbating bridge overturning. To investigate the association between temperature and bridge overturning, an explicit finite element model (EFEM) of a three-span concrete curved continuous bridge considering nonlinearities was developed to simulate overall collapse. The effects of uniform and gradient temperatures on the overall overturning stability of curved and straight bridges were evaluated based on the EFEMs. Furthermore, the temperature-bridge coupling model and temperature-vehicle-bridge coupling model were utilized to examine how gradient temperature influences bridge overturning. The results show that the overall overturning collapse of a bridge follows four stages: stabilization, transition, risk and overturning. Variations in uniform temperature from -30 °C to 60 °C had a negligible effect on the ultimate vehicle weight for bridge overturning, with a variation of less than 1%. As the gradient temperature ranged from -30 °C to 60 °C, curved bridges show less than a 2% variation in ultimate vehicle weights, compared to a range of -6.1% to 11.7% for straight bridges. The torsion caused by positive gradient temperature in curved bridges can exacerbate bridge overturning, while negative gradient temperature in straight bridges can lead the girder to 'upward warping', facilitating girder separation from bearings. Monitoring the girder rotation angle and vertical reaction force of bearings can serve as important indicators for comparing the stability of bridges.

7.
Materials (Basel) ; 17(11)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38893957

RESUMO

This study presents a new approach to investigating the impact of repeated reflow on the failure of ball grid array (BGA) packages. The issue with the BGA package collapse is that the repeated reflow can lead to short circuits, particularly for BGAs with a very fine pitch between leads. A novel approach was developed to measure the collapse of BGA solder balls during the melting and solidification process, enabling in situ measurements. The study focused on two types of solders: Sn63Pb37 as a reference, and the commonly used SAC305, with measurements taken at various temperatures. The BGA samples were subjected to three different heating/cooling cycles in a thermomechanical analyzer (TMA) at temperatures of 250 °C, 280 °C, and 300 °C, with a subsequent cooling down to 100 °C. The results obtained from the TMA indicated differences in the collapse behavior of both BGA solder alloys at various temperatures. Short circuits between neighboring leads (later confirmed by an X-ray analysis) were also recognizable on the TMA. The novel approach was successfully developed and applied, yielding clear insights into the behavior of solder balls during repeated reflow.

8.
J Pharm Sci ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38906251

RESUMO

In pharmaceutical freeze-drying processes, batch homogeneity is an important quality attribute. In this context, the edge-vial-effect is a challenging phenomenon. Shortly, this effect describes that vials at the edges of the shelf dry faster and at a higher temperature compared to vials in the middle of the shelf. Studies by Ehlers et al. revealed that this effect mainly origins from the number of neighbor vials cooling each other, which is reduced for vials in corners and edges compared to vials in the middle. Due to the reduced heat transfer in cyclic olefin polymer (COP) vials, the adverse edge-vial-effect should be greatly reduced allowing a better batch uniformity. In this focused study, glass and COP vials are compared regarding this effect on a fully loaded shelf. A reference experiment with vials placed at distance using a specially designed frame is presented as well.

9.
J Anim Ecol ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867406

RESUMO

Climate change is impacting ecosystems worldwide, and the Mediterranean Sea is no exception. Extreme climatic events, such as marine heat waves (MHWs), are increasing in frequency, extent and intensity during the last decades, which has been associated with an increase in mass mortality events for multiple species. Coralligenous assemblages, where the octocoral Paramuricea clavata lives, are strongly affected by MHWs. The Medes Islands Marine Reserve (NW Mediterranean) was considered a climate refugia for P. clavata, as their populations were showing some resilience to these changing conditions. In this study, we assessed the impacts of the MHWs that occurred between 2016 and 2022 in seven shallow populations of the octocoral P. clavata from a Mediterranean Marine Protected Area. The years that the mortality rates increased significantly were associated with the ones with strong MHWs, 2022 being the one with higher mortalities. In 2022, with 50 MHW days, the proportion of total affected colonies was almost 70%, with a proportion of the injured surface of almost 40%, reaching levels never attained in our study site since the monitoring was started. We also found spatial variability between the monitored populations. Whereas few of them showed low levels of mortality, others lost around 75% of their biomass. The significant impacts documented here raise concerns about the future of shallow P. clavata populations across the Mediterranean, suggesting that the resilience of this species may not be maintained to sustain these populations face the ongoing warming trends.


El canvi climatic està impactant els ecosistemes arreu del planeta, i el Mar Mediterrani no n'és una excepció. Els esdeveniments climàtics extrems, com ara les onades de calor marines, estan augmentant en freqüència, extensió i intensitat en les darreres dècades, i estan sent associades a un increment dels esdeveniments de mortalitat massiva de múltiples espècies. El coral·ligen, on hi viu l'octocorall Paramuricea clavata, està altament afectat per les onades de calor marines. La Reserva Marina de les Illes Medes (NO del Mediterrani) es considerava un refugi climàtic per aquesta espècie, degut a que les seves poblacions mostraven certa resiliència a les condicions canviants. En aquest estudi hem avaluat els impactes de les onades de calor marines succeïdes entre els anys 2016 i 2022 a set poblacions someres de l'octocorall P. clavata, en una Àrea Marina Protegida del Mediterrani. Els anys en els quals les taxes de mortalitat van incrementar significativament s'associen amb els anys amb fortes onades de calor marines, sent el 2022 l'any amb la mortalitat més elevada. Al 2022, amb 50 dies d'onada de calor, la proporció total de colònies afectades va ser prop del 70%, amb un percentatge de superfície afectada de gairebé el 40%, arribant a valors mai observats en el lloc d'estudi des de que es va iniciar el seguiment d'aquestes poblacions. També hem observat variabilitat espacial entre les poblacions mostrejades. Mentre que algunes d'elles han mostrat poca mortalitat, altres han perdut al voltant del 75% de la seva biomassa. Els impactes documentats en aquest estudi mostren un futur preocupant de les poblacions someres de P. clavata arreu del Mediterrani, i això suggereix que la resiliència d'aquesta espècie podria no ser suficient per mantenir les seves poblacions en l'escenari d'escalfament que es preveu.

10.
Reprod Biomed Online ; 49(2): 103941, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38824764

RESUMO

RESEARCH QUESTION: Does artificial shrinkage before fresh blastocyst transfer improve clinical pregnancy rates in IVF? DESIGN: In this monocentric prospective, randomized, double-blind, controlled pilot study, 150 couples undergoing fresh single-blastocyst transfer were randomized between 20 May 2018 and 22 February 2022. In the artificial shrinkage group (AS group), a single laser pulse was directed to the cellular junction of the trophectoderm on the opposite side of the inner cell mass in each blastocyst. IVF outcomes were clinical pregnancy, multiple pregnancy and live birth rates. Cell-free DNA (cfDNA) concentration was also measured by quantitative real-time PCR in the blastocyst culture medium. RESULTS: In total, 142 couples underwent fresh single-blastocyst transfer: control group, no artificial shrinkage, n = 47; and AS group, artificial shrinkage, n = 95; An intention-to-treat (ITT) analysis was employed. After a reassessment and the exclusion of patients with major protocol deviations, 139 couples underwent fresh single-blastocyst transfer under optimal conditions: control group, n = 47; and AS group, n = 92; a per-protocol analysis was used here. The clinical and laboratory characteristics were not significantly different between the groups. The clinical pregnancy rate was similar in the control and AS groups (ITT: 48.9% versus 49.5%, P = 0.97; per protocol: 48.94% versus 51.1%, P = 0.89). The multiple pregnancy rate and the live birth rate were also similar between the groups. No significant differences in gestational age, birthweight or proportion of male/female newborns were observed. The concentration of cfDNA in the blastocyst culture medium was not associated with IVF outcome. CONCLUSIONS: Large-scale randomized controlled trials are required to confirm these preliminary results.

11.
J Vet Intern Med ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822531

RESUMO

BACKGROUND: Stenting has become popular to treat tracheal collapse in dogs, but complications might arise and negatively affect treatment outcome. OBJECTIVES: Determine the overall prevalence of complications of tracheal stenting in dogs. METHODS: A bibliographic search was performed of publications from 2000 to 2020. Studies were assessed for quality of evidence and measured prevalence of the 8 most commonly reported complications after tracheal stenting in dogs (stent fracture, stent migration, relapsing collapse, granuloma formation, tracheobronchial infections, and early, late, and clinically relevant late cough). Random effects meta-analyses were used to estimate pooled complications prevalence. RESULTS: Fifteen studies met inclusion criteria. Cough (early: 99%; 95% confidence interval [95% CI]: 95%-100%, late: 75%; 95% CI: 63%-85%, and clinically relevant: 52%; 95% CI: 42%-61%), tracheobronchial infections (24%; 95% CI: 14%-35%), and granulomas (20%; 95% CI: 11%-30%) were common after tracheal stenting. Stent fractures (12%; 95% CI: 5%-20%), relapsing collapse (10%; 95% CI: 5%-15%), and stent migration (5%; 95% CI: 1%-9%) were less frequent. Significant heterogeneity among studies was identified for the estimated prevalence of stent fracture, granulomas, infections, and late cough. CONCLUSIONS AND CLINICAL IMPORTANCE: Tracheal stenting in dogs is associated with a high risk of coughing and a moderate risk of tracheobronchial infections and granuloma formation. Because most complications will impact a dog's quality of life, owners must be informed that tracheal stenting is a second-line procedure that does not necessarily alleviate the need for medical treatment and frequent follow-up visits. Additional studies are warranted to identify the risk factors of these complications.

12.
J Anim Ecol ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38859669

RESUMO

Ecological networks comprising of mutualistic interactions can suddenly transition to undesirable states, such as collapse, due to small changes in environmental conditions such as a rise in local environmental temperature. However, little is known about the capacity of such interaction networks to adapt to a rise in temperature and the occurrence of critical transitions. Here, combining quantitative genetics and mutualistic dynamics in an eco-evolutionary framework, we evaluated the stability and resilience of mutualistic networks to critical transitions as environmental temperature increases. Specifically, we modelled the dynamics of an optimum trait that determined the tolerance of species to local environmental temperature as well as to species interaction. We then evaluated the impact of individual trait variation and evolutionary dynamics on the stability of feasible equilibria, the occurrence of threshold temperatures at which community collapses, and the abruptness of such community collapses. We found that mutualistic network architecture, that is the size of the community and the arrangement of species interactions, interacted with evolutionary dynamics to impact the onset of network collapses. Some networks had more capacity to track the rise in temperatures than others and thereby increased the threshold temperature at which the networks collapsed. However, such a result was modulated by the amount of heritable trait variation species exhibited, with high trait variation in the mean optimum phenotypic trait increasing the environmental temperature at which networks collapsed. Furthermore, trait variation not only increased the onset of temperatures at which networks collapsed but also increased the local stability of feasible equilibria. Our study argued that mutualistic network architecture interacts with species evolutionary dynamics and increases the capacity of networks to adapt to changes in temperature and thereby delayed the occurrence of community collapses.

13.
Int Orthop ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38898160

RESUMO

PURPOSE: The acetabular coverage in osteonecrosis of the femoral head (ONFH) affects the need for surgical intervention, and the collapse of the femoral head remains unclear. This study aimed to evaluate the relation between the acetabular coverage and the need for surgical treatment and femoral head collapse. METHODS: The study included 158 patients with 252 hips with glucocorticoid administration and idiopathic ONHF without osteoarthritis changes. The mean age at the first visit was 45.2 years, and the mean follow-up period was 92.2 months. All ONFH hips were subsequently divided into two groups: those needing surgical intervention and those without surgery. Additionally, it divided 167 initially non-collapsed hips into those that either later collapsed or not. Radiographic parameters with the centre-edge angle, acetabular roof obliquity, sharp angle, and necrotic location, following the guidelines of the Japanese Investigation Committee, were evaluated. RESULTS: There were no significant differences in radiographic parameters between the 106 hips that underwent surgery and the 146 hips without surgery. Among the 167 hips without initial collapse, 91 eventually collapsed while 76 did not; their radiographic findings have no significant differences. The necrotic locations were significantly larger in hips requiring surgical intervention or femoral head collapse. Furthermore, 21.8% (55 out of 252 hips) had acetabular dysplasia, which did not significantly correlate with the necessity for surgical treatment or the incidence of femoral head collapse. CONCLUSIONS: Acetabular coverage has little effect on the necessity for surgical treatment and femoral head collapse in ONFH patients over a long-term follow-up.

14.
Sci Rep ; 14(1): 13900, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886402

RESUMO

In order to reveal the disastrous mechanism of seepage instability of karst collapse column considering variable mass effect, a variable mass fluid-solid coupling mechanical model of water inrush is established, by considering the random distribution characteristics of a collapse column. Taking Qianjin coal mine as the research background, based on the Weibull distribution theory, the heterogeneous distribution characteristics of rock mass is described, and COMSOL Multiphysics numerical simulation software is employed to simulate the seepage characteristics and inrush water changes in collapse columns under different conditions of homogeneity, water pressure, and initial porosity. The research results show that the greater the homogeneity is, the more water conduction channels are formed, and the porosity increases accordingly, when considering the influence of different homogeneity on the seepage characteristics of broken rock mass, which eventually leads to water inrush accidents and a sharp increase in water inflow. Besides, when studying the seepage evolution law of different water pressures on a broken rock mass, an elevation of water pressure dramatically increases the porosity and seepage rate of the water. Over time, the broken rock particles gradually migrate and the fine particles are transported and eroded by the water flow, resulting in changes in the seepage characteristics and the formation of potential water diversion channels. Finally, when taking into account the effect of different initial porosity on the fractured rock mass seepage characteristics, the greater the original porosity is, the higher the seepage velocity is, and the particle migration increases the permeability. This leads to a more pronounced conductive water passage formation, which reveals the disastrous mechanism of seepage instability of karst collapse column considering variable mass effect.

15.
Cureus ; 16(5): e61169, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38933628

RESUMO

Hypothyroidism is a condition characterized by low thyroid hormone levels that can affect multiple organ systems with varying symptomatology. Common cardiac manifestations of hypothyroidism include bradycardia and decreased cardiac output. Pericardial effusion can also occur as a result of the condition and rarely can progress to cardiac tamponade. Patients with cardiac tamponade occurring as a result of underlying hypothyroidism can present atypically compared to those experiencing cardiac tamponade due to other causes. Patients with cardiac tamponade as a result of underlying hypothyroidism may present as minimally symptomatic with stable vital signs. Close monitoring of patients with pericardial effusions with underlying hypothyroidism is essential to permit early diagnosis and treatment of the condition. We outline the case of a 73-year-old male presenting with cardiac tamponade due to underlying hypothyroidism necessitating an urgent pericardial window.

16.
Cureus ; 16(6): e62873, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38915842

RESUMO

Bupropion is an antidepressant used in the treatment of major depressive disorder, seasonal affective disorder, nicotine addiction, and weight loss. It primarily functions via norepinephrine and dopamine reuptake inhibition. At toxic doses, bupropion can elicit seizures, as well as precipitate corrected QT interval (QTc) and QRS prolongation. We describe a case of an 18-year-old female who reportedly ingested 28 grams of extended-release bupropion, a dose much higher than in previously reported cases. Toxic ingestion precipitated status epilepticus, prolonged QTc, widened QRS, pulseless ventricular tachycardia (pVT), and subsequent cardiovascular collapse necessitating veno-arterial extracorporeal membrane oxygenation (ECMO) and Impella support. Historically, the cardiotoxic effects of bupropion toxicity have largely been treated with supportive care, sometimes requiring ECMO. This patient's course was complicated by a widening QRS despite aggressive bicarbonate therapy and recurrent pVT, which was ultimately aborted with lidocaine. Neurological prognostication was further complicated by a lack of brainstem reflexes on the exam. With maximal supportive care, the patient was liberated from Impella, ECMO, and the ventilator by hospital day seven. At discharge, she was neurologically intact with full recovery of cardiac function. This case emphasizes the need for early consideration of transfer to an ECMO center in the setting of a bupropion overdose and offers a potentially effective treatment option for bupropion-induced ventricular arrhythmia.

17.
ACS Nano ; 18(26): 16982-16993, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38900971

RESUMO

The structure collapse issues have long restricted the application of polycrystalline LiNixCoyMn1-x-yO2 (NCM) at high voltages beyond 4.4 V vs Li/Li+. Herein, for LiNi0.55Co0.12Mn0.33O2 (P-NCM), rapid surface degradation is observed upon the first charge, along with serious particle fragmentation upon repeated cycles. To alleviate these issues, a surface Co enrichment strategy is proposed [i.e., Co-enriched NCM (C-NCM)], which promotes the in situ formation of a robust surface rock-salt (RS) layer upon charge, serving as a highly stable interface for effective Li+ migration. Benefiting from this stabilized surface RS layer, Li+ extraction occurs mainly through this surface RS layer, rather than along the grain boundaries (GBs), thus reducing the risk of GBs' cracking and even particle fragmentation upon cycles. Besides, O loss and TM (TM = Ni, Co, and Mn) dissolution are also effectively reduced with fewer side reactions. The C-NCM/graphite cell presents a highly reversible capacity of 205.1 mA h g-1 at 0.2 C and a high capacity retention of 86% after 500 cycles at 1 C (1 C = 200 mA g-1), which is among the best reported cell performances. This work provides a different path for alleviating particle fragmentation of NCM cathodes.

18.
FEBS Open Bio ; 14(7): 1147-1165, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38760979

RESUMO

Continuous fusion and fission are critical for mitochondrial health. In this study, we further characterize the role played by dynamin-related protein 1 (Drp1) in mitochondrial fission. We show that a single amino acid change in Drp1 at position 39 from serine to alanine (S39A) within the GTP-binding (GTPase) domain results in a fused mitochondrial network in human SH-SY5Y neuroblastoma cells. Interestingly, the phosphorylation of Ser-616 and Ser-637 of Drp1 remains unaffected by the S39A mutation, and mitochondrial bioenergetic profile and cell viability in the S39A mutant were comparable to those observed in the control. This leads us to propose that the serine 39 residue of Drp1 plays a crucial role in mitochondrial distribution through its involvement in the GTPase activity. Furthermore, this amino acid mutation leads to structural anomalies in the mitochondrial network. Taken together, our results contribute to a better understanding of the function of the Drp1 protein.


Assuntos
Dinaminas , Mitocôndrias , Dinâmica Mitocondrial , Serina , Humanos , Dinaminas/metabolismo , Dinaminas/genética , Mitocôndrias/metabolismo , Serina/metabolismo , Serina/genética , Dinâmica Mitocondrial/genética , Guanosina Trifosfato/metabolismo , Linhagem Celular Tumoral , Fosforilação , Mutação , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/genética
19.
Environ Toxicol Pharmacol ; 108: 104473, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38759846

RESUMO

The most recent dam rupture in Brazil released tons of mining tailings into the upper course of the Paraopeba River, affecting this river in an unprecedented way. The present study aimed to evaluate the influence of heavy metals on Prochilodus costatus, an important commercial species in Brazil, four years after the dam colapse. To this end, biomarkers of heavy metals, oxidative stress, and environmental stress were analyzed, and histological analyses of target organs were performed. The results demonstrated critical contamination of fish from the Paraopeba River. Increased expression of Metallothioneins - MTs, Heat Shock Protein - HSP70, and inducible nitric oxide synthase - iNOS, as well as greater rates of histological changes in the liver, spleen, and gonads, were observed in P. costatus. These findings demonstrate that, despite past contamination, the metals present in mining tailings have significantly increased the contamination of the Paraopeba River basin.


Assuntos
Fígado , Metalotioneína , Metais Pesados , Óxido Nítrico Sintase Tipo II , Rios , Poluentes Químicos da Água , Animais , Metalotioneína/metabolismo , Poluentes Químicos da Água/toxicidade , Metais Pesados/toxicidade , Óxido Nítrico Sintase Tipo II/metabolismo , Brasil , Fígado/efeitos dos fármacos , Fígado/metabolismo , Baço/efeitos dos fármacos , Baço/metabolismo , Caraciformes/metabolismo , Masculino , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Peixes/metabolismo , Feminino
20.
Am J Otolaryngol ; 45(4): 104338, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38729012

RESUMO

PURPOSE: Nasal obstruction is a prevalent issue affecting up to one-third of adults, often requiring surgical intervention. Low-temperature radiofrequency (RF) treatment, specifically VivAer, has emerged as a promising alternative, especially for the treatment of nasal valve collapse (NVC). However, its efficacy in patients with a history of rhinoplasty or nasal valve repair remains unexplored. METHODS: A single-center retrospective chart review was conducted on 37 patients with a history of rhinoplasty or nasal valve repair who underwent VivAer RF treatment. Treatment outcomes were assessed using the Nasal Obstruction Symptom Evaluation (NOSE) scale. The primary outcome was defined as a decrease in NOSE score by at least one severity category or a 20 % reduction in total NOSE score. RESULTS: The study found a statistically significant average reduction in NOSE score of 22.4 points or 36.6 %. Among patients with a positive treatment response (21 patients or 56.8 %), the average NOSE score reduction was 34.7 points or 55.6 %. Repeat RF treatment in non-responders resulted in a 50 % response rate. No significant difference was observed in treatment outcomes based on the type of prior rhinoplasty or NVC. CONCLUSIONS: Temperature-controlled RF treatment with VivAer can effectively alleviate nasal obstruction in patients with a history of rhinoplasty or nasal valve repair, offering a viable alternative to revision surgery. The study also highlights the potential benefit of repeat RF treatment in non-responders. Further research, including randomized controlled trials, is needed to validate these promising results and expand the treatment options for this complex patient population.


Assuntos
Obstrução Nasal , Ablação por Radiofrequência , Rinoplastia , Humanos , Obstrução Nasal/cirurgia , Obstrução Nasal/etiologia , Rinoplastia/métodos , Feminino , Masculino , Estudos Retrospectivos , Adulto , Resultado do Tratamento , Ablação por Radiofrequência/métodos , Pessoa de Meia-Idade , Adulto Jovem , Idoso
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