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1.
Technol Health Care ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39093086

RESUMO

BACKGROUND: Atherosclerosis is a condition which disrupts blood flow due to plaque build-up inside the arteries. Under conditions where consecutive plaques are prevailing blood hammer principle is exhibited. OBJECTIVE: The pressure and shear stress produced at an infinitesimal area act as the governing equation for stent modeling. The leading order pressure lays the foundation for the design of cardiac stents with definite dimensions. METHOD: The designed stent was encapsulated inside a crimper validated through ANSYS-static and transient structural simulation to derive the total deformation, equivalent strain, and stress exerted on the stent. Five different biomaterials stainless steel 316, cobalt, chromium, platinum, and Poly lactic acid were selected for the material assessment. RESULT: Static and Transient structural analysis for a period of 1 and 10 secs was implemented for a stent with and without a crimper. The material performance in terms of total deformation, equivalent stress, and strain are analyzed. CONCLUSION: The paper envisions the dynamics of blood hammer in atherosclerosis that provides the changes in the pressure and clotting process. It shows the promising results of the stent behavior in varied forces which gives valuable insights for future improvement in stent design and material selection.

2.
JMIR Form Res ; 8: e54009, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088821

RESUMO

BACKGROUND: A coordinated care system helps provide timely access to treatment for suspected acute stroke. In Northwestern Ontario (NWO), Canada, communities are widespread with several hospitals offering various diagnostic equipment and services. Thus, resources are limited, and health care providers must often transfer patients with stroke to different hospital locations to ensure the most appropriate care access within recommended time frames. However, health care providers frequently situated temporarily (locum) in NWO or providing care remotely from other areas of Ontario may lack sufficient information and experience in the region to access care for a patient with a time-sensitive condition. Suboptimal decision-making may lead to multiple transfers before definitive stroke care is obtained, resulting in poor outcomes and additional health care system costs. OBJECTIVE: We aimed to develop a tool to inform and assist NWO health care providers in determining the best transfer options for patients with stroke to provide the most efficient care access. We aimed to develop an app using a comprehensive geomapping navigation and estimation system based on machine learning algorithms. This app uses key stroke-related timelines including the last time the patient was known to be well, patient location, treatment options, and imaging availability at different health care facilities. METHODS: Using historical data (2008-2020), an accurate prediction model using machine learning methods was developed and incorporated into a mobile app. These data contained parameters regarding air (Ornge) and land medical transport (3 services), which were preprocessed and cleaned. For cases in which Ornge air services and land ambulance medical transport were both involved in a patient transport process, data were merged and time intervals of the transport journey were determined. The data were distributed for training (35%), testing (35%), and validation (30%) of the prediction model. RESULTS: In total, 70,623 records were collected in the data set from Ornge and land medical transport services to develop a prediction model. Various learning models were analyzed; all learning models perform better than the simple average of all points in predicting output variables. The decision tree model provided more accurate results than the other models. The decision tree model performed remarkably well, with the values from testing, validation, and the model within a close range. This model was used to develop the "NWO Navigate Stroke" system. The system provides accurate results and demonstrates that a mobile app can be a significant tool for health care providers navigating stroke care in NWO, potentially impacting patient care and outcomes. CONCLUSIONS: The NWO Navigate Stroke system uses a data-driven, reliable, accurate prediction model while considering all variations and is simultaneously linked to all required acute stroke management pathways and tools. It was tested using historical data, and the next step will to involve usability testing with end users.

3.
Chem Biol Interact ; : 111181, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39089414

RESUMO

Tanshinone IIA (TSA), the main lipo-soluble component from the dried rhizome of Salvia miltiorrhiza, has been shown to induce vasodilation. However, the underlying mechanisms remains unclear. This study aimed to investigate the effect of TSA on the vasodilation of small resistant arteries ex vivo. Vascular myography revealed that endothelial denudation reduced significantly the vasodilatory effect of TSA. Blocking transient receptor potential vanilloid 4 (TRPV4) channels prevented TSA-induced vasodilation. Whole-cell patch-clamp analysis revealed that the current passing through TRPV4 channels increased after TSA treatment in endothelial cells (ECs). This was attributed to reduced TRPV4 protein degradation along with its increased expression. The TRPV4 inhibitor HC-067047 lowed nitric oxide (NO) production and TSA-induced expression of endothelial nitric oxide synthase (eNOS). Moreover, it increased the production of cyclic guanosine monophosphate (cGMP) and protein kinase G (PKG). The present results indicate that TSA induces endothelium-dependent vasodilation, which is mediated by the TRPV4-NO-PKG signaling pathway. These findings highlight the potential of TSA, a compound known in traditional Chinese medicine as Danshen (Salvia miltiorrhiza), for future cardiovascular therapeutic strategies.

4.
Paediatr Respir Rev ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39089954

RESUMO

INTRODUCTION: Respiratory distress (RD) is the most common cause of admission to the Neonatal Intensive Care Unit (NICU). The role of Vitamin D in the development and fortification of fetal pulmonary architecture and the synthesis of surfactants is well-documented. While different serum levels of 25-hydroxyvitamin D (Vit. D) have been studied for their diagnostic significance in RD, there is limited research on how it specifically affects the development of respiratory problems in infants and their mothers. The purpose of the present study is a systematic review and meta-analysis to evaluate the correlation between serum levels of Vit. D in mothers and newborns with RD, and to determine the impact of treating either population on the clinical outcomes of afflicted infants. METHODS: A comprehensive literature search was conducted across various databases, including PubMed, ScienceDirect, Cochrane Library, ISI, and Google Scholar, using a combination of keywords such as RD, diagnosis, vitamin D, mothers, infants, vitamin D supplementation, Respiratory distress syndrome(RDS), and Transient Tachypnea of Newborn (TTN). The search was carried out until March 2024.The level of vitamin D in both mothers and their infants was systematically extracted and analyzed to determine the diagnostic efficacy of Vit. D levels. The mean difference (MD) was calculated along with a 95% confidence interval to determine the association between the Vit. D levels in newborns and their mothers and the likelihood of RD, RDS and TTN in infants. To assess potential publication bias, a funnel plot was generated and Egger's regression test was applied, utilizing a random-effects model. RESULTS: Initially a total of 298 relevant articles was retrieved. Among them, 17 articles with a total of 1,582 infants (745 cases and 837 healthy controls) met the criteria as eligible studies. Of these six were prospective cohort studies, four retrospective case-control studies, four randomized controlled trials (RCTs), and three descriptive-analytical studies. The meta-results revealed a significant association between Vit. D levels and risk of RD in infants (MD = 6.240, 95 %CI: 4.840-7.840, P < 0.001) and mothers (MD = 8.053, 95 %CI: 4.920-11.186, P < 0.001). Furthermore, a strong association was found for risk of RDS (MD = 5.493, 95 %CI: 3.356-7.631, P < 0.001) in infants and TTN (MD = 6.672, 95 %CI: 4.072-9.272, P < 0.001), (MD = 8.595, 95%CI: 4.604-12.586, P < 0.001) both in infants and mothers. Administering 50,000 units of vitamin D to mothers (MD = 8.595, 95 %CI: 4.604-12.586, P < 0.001) prior to childbirth was observed to reduce the likelihood of RD in newborns by 64 % (RR = 0.36, 95 %CI: 0.23-0.57, P < 0.001). Supplemental vitamin D provided to infants was associated with several clinical benefits. CONCLUSION: Our meta-results indicated a significant correlation between serum levels of Vit. D and the risk of RD, RDS and TTN in infants. Prophylactic maternal administration of vitamin D plays a protective role against neonatal RD. Additionally, providing vitamin D to premature infants has shown a significant impact in reducing the incidence of respiratory complications.

5.
HIV Med ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39091015

RESUMO

OBJECTIVES: People with HIV are at increased risk for metabolic dysfunction-associated steatohepatitis (MASH). Although sex differences are documented in the general population, their role in the context of HIV is less understood. METHODS: This was a multicentre cohort study including people with HIV without viral hepatitis coinfection. A FibroScan-AST (FAST) score >0.35 was used to diagnose MASH with significant liver fibrosis (stage F2-F4). We investigated sex-based differences in MASH trends as a function of age using a segmented linear mixed-effects model. Random effects accounted for clustering by the four sites. Adjusted models included ethnicity, diabetes, hypertension, and detectable HIV viral load. RESULTS: We included 1472 people with HIV (25% women). At baseline, the prevalence of MASH with fibrosis by FAST score was lower in women than in men (4.8% vs. 9.2%, p = 0.008). Based on the adjusted model, male sex (+0.034; p = 0.04), age per year (+0.003; p = 0.05), detectable HIV viral load (+0.034; p = 0.02), and hypertension (+0.03; p = 0.01) were positively associated with MASH with fibrosis. Although men exhibited generally higher FAST scores, FAST scores increased in women during the critical biological age of presumed perimenopause to menopause (between 40 and 50 years), reaching levels similar to those in men by the age of 55 years. CONCLUSION: Despite women with HIV having a lower prevalence of MASH with fibrosis than men, they exhibit an acceleration in FAST score increase around the perimenopausal age. Future studies should target adequate consideration of sex differences in clinical investigation of metabolic dysfunction-associated steatotic liver disease to fill current gaps and implement precision medicine for people with HIV.

6.
Chemistry ; : e202402192, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39087763

RESUMO

In this work, we used photoinert anhydrous cerium(III) chloride, to form a transient charge-transfer (CT) complex with NXS (N-bromosuccinimide or NBS and N-iodosuccinimide or NIS) in acetonitrile. These transient CT complexes acted as a semi-heterogeneous photocatalyst. These complexes allowed the Ce(III) ions to absorb light, turning them into strong electron donors that transferred electrons to NXS. This created halide radicals from NXS radical anions, helping to turn N-propargylamides into oxazole aldehydes. Experiments with DMPO and spin-trapping showed that a radical-based mechanism followed a single electron transfer (SET) pathway. Notably, CeCl3 was reused after the reaction without much decomposition, as it was regenerated and separated through simple filtration.

7.
Front Cardiovasc Med ; 11: 1401974, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39091357

RESUMO

Background: Percutaneous interventional left atrial appendage occlusion (LAAO) is a reliable, safe, and effective alternative for stroke prevention in selected patients with atrial fibrillation (AF). Methods: In a retrospective observational study, 149 patients underwent LAAO between 2016 and 2022 at the Department of Cardiology of the Charité-Universitätsmedizin Berlin, Campus Virchow, with AF for prevention of thromboembolic complications. We compared patient characteristics, intraoperative details and postoperative outcomes between single-occlusive plug-type (SOPT) and dual-occlusive disc-type (DODT) devices. Results: In all patients, the device implantation was successful. 60 patients received a SOPT occluder, including Watchman (35%) and Watchman FLX Occluders (65%), while 89 patients received a DODT occluder, including Amplatzer Cardiac Plug (37.1%), the Amplatzer Amulet (25.8%), and the LAmbre occluder (37.1%) systems. Procedure duration was significantly longer for DODT occluder implantation (49 ± 33 vs. 41 ± 25 min, p = 0.018). There were no in-hospital deaths or thromboembolic events reported after LAAO in both groups. Beyond that, a low rate of bleeding or access-side-related complications and pericardial tamponades were observed. Anticoagulation at discharge varied. About 60.8% of patients received dual antiplatelet therapy at hospital discharge, and 33.1% received direct oral anticoagulants. A 6-month follow-up was obtained in 85% of the patients. All implanted devices were in the desired position. However, in 5.7% of the patients, a device-related thrombus formation was detected in the SOPT group, while no thrombus was seen in the DODT group (p = 0.11). Thromboembolic events were noticed in 3.1%, without any difference between the device types. There was a statistically non-significant trend for less residual device leaks after SOPT vs. DODT implantation (no leak in 71.7% vs. 62.2%, p = 0.07; minor leaks <5 mm, 9.4% vs. 20.3%, p = 0.1). In the SOPT group, less bleeding complications were reported after LAAO (11.3% vs. 17.6%, p = 0.1). Conclusion: Our data suggest the safety and efficiency of LAAO with a very high procedural implantation success rate irrespective of the used LAA device. Furthermore, no relevant procedural or device-related complication occurred during the 6-month follow-up in all patients.

8.
J Med Cases ; 15(8): 159-166, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39091574

RESUMO

Transient global amnesia (TGA) is a benign and transient condition with a sudden short-term amnesia. One of the conditions resembling TGA is hippocampal infarction, which requires relapse prevention treatments. In this report, we present a case with bilateral hippocampal infarction in whom distinguishing these two conditions was difficult for up to 1 week from the onset. A 60-year-old female visited our hospital with sudden onset retrograde and anterograde amnesia. Thin-slice magnetic resonance imaging (MRI) with 2-mm thickness revealed hyperintense signals on diffusion-weighted imaging (DWI) with signal loss on apparent diffusion coefficient (ADC) on both sides of the hippocampus. MRI with 5-mm thickness on day 7 revealed persistent restricted diffusion on both sides, one of which was still with decreased ADC values. Based on this finding, the diagnosis of bilateral hippocampal infarction was reached, and the relapse-preventive antiplatelet was continued. This case implied the potential difficulty of distinguishing cases with TGA and those with hippocampal infarction based on MRI findings within the first several days after onset. Thin-slice brain MRI, careful search of potential cardiovascular risks, and follow-up MRI ≥ 7 days after onset will be helpful to reach a correct diagnosis in cases with sudden amnesia.

9.
Cureus ; 16(7): e63658, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39092367

RESUMO

Introduction Chronic liver disease progression leads to liver fibrosis/cirrhosis. Transient Elastography is used for staging liver fibrosis but ascites, obesity, and operator experience limit its applicability. In this study, we compared various non-invasive serum indices in predicting fibrosis in chronic liver disease patients. Materials and methods A total of 142 cases of confirmed Chronic Liver Disease were included. Quantitative determination of liver stiffness by Transient Elastography and relevant blood investigations was done. We compared the liver stiffness measurement by Transient Elastography and fibrosis indices, i.e., Aspartate Transaminase (AST) to Alanine Transaminase (ALT) Ratio (AAR), AST to Platelet Ratio Index (APRI), Fibrosis Index (FI), Fibrosis-4 (FIB-4) Index, Age-Platelet Index (API), Pohl score, and Fibrosis Cirrhosis Index (FCI) with Novel Fibrosis Index (NFI), to predict liver fibrosis stages. Results The optimum cutoff of NFI for the F4 stage was ≥ 6670 with a sensitivity of 75.8% and specificity of 81.8%, for the F3 stage was ≥ 2112 with a sensitivity of 63.6% and specificity of 72.7%, and for the F2 stage was ≥ 1334 with a sensitivity of 100% and specificity of 56.3%. The NFI had the maximum area under the curve compared to other indices in predicting fibrosis stages. Conclusion The Novel Fibrosis Index was the best in predicting fibrosis stages in Chronic Liver Disease patients, with good performance in predicting the F4 stage.

10.
Am J Cardiol ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39097151

RESUMO

BACKGROUND: Transcatheter mitral edge-to-edge repair (TEER) with transcatheter devices has become a mainstay in the minimally invasive treatment of patients with severe mitral regurgitation at increased surgical risk. Despite its apparently favorable risk profile, there is uncertainty on the risk and features of cerebrovascular accidents (CVA) early and long after TMVR. We aimed at appraising incidence and predictors of CVA in patients undergoing TEER. METHODS: We explicitly queried the dataset of an ongoing multicenter prospective observational study dedicated to TEER with MitraClip (Abbott Vascular, Santa Clara, CA, USA). Incidence of CVA after TEER was formally appraised, and we explored also potential predictors of such event. Descriptive, bivariate and diagnostic accuracy analyses were performed. RESULTS: Out of 2238 patients undergoing TEER, CVA occurred in 33 (1.47% [95% confidence interval 1.02% to 2.06%]), including 6 (0.27% [0.10% to 0.58%]) inhospital strokes and 27 events after discharge (0.99% [0.66% to 1.44%]) over a median follow-up of of 14 months. Most CVA were major ischemic strokes, during the inhospital phase as well as subsequently. Overall, CVA were more common in patients with atrial fibrillation (p=0.018), renal dysfunction (p=0.032), higher EuroSCORE II (p=0.033), and, as expected, higher CHA2DS2-VASc score (p=0.033), despite the limited prognostic accuracy of such score. Notably, the occurrence of CVA did not confer a significantly increased risk of long-term death (p=0.136) or cardiac death (p=0.397). CONCLUSIONS: The incidence of CVA in patients undergoing TEER is low, with most events occurring after discharge, and being associated with pre-existing risk features. These findings, while reassuring on the safety of TEER, call for proactive antithrombotic therapy whenever CVA risk is increased before, as well as after such intervention.

11.
BMC Gastroenterol ; 24(1): 221, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987694

RESUMO

BACKGROUND: Obesity has become a major global public health challenge. Studies examining the associations between different obesity patterns and the risk of nonalcoholic fatty liver disease (NAFLD) are limited. This study aimed to investigate the relationships between different obesity patterns and the risk of NAFLD in a large male population in the US. METHODS: Data from the 2017 to March 2020 National Health and Nutrition Examination Survey (NHANES) were utilized. Liver steatosis and fibrosis were assessed with FibroScan using the controlled attenuation parameter (CAP) and liver stiffness measurements (LSM). Steatosis was identified with a CAP value of 248 dB/m or higher. Abdominal obesity was defined by a waist circumference (WC) of 102 cm or more for males and 88 cm or more for females. Overweight was defined as a body mass index (BMI) of 24.0 kg/m2 and above. General obesity was identified with a BMI of 28.0 kg/m2 or higher. Obesity status was categorized into four types: overweight, general obesity, abdominal obesity, and combined obesity. Multivariate logistic regression, adjusting for potential confounders, was used to examine the link between obesity patterns and NAFLD risk. Subgroup analysis further explored these associations. RESULTS: A total of 5,858 adults were included. After multivariable adjustment, compared to the normal weight group, the odds ratios (ORs) [95% confidence interval (CI)] for NAFLD in individuals with overweight, general obesity, abdominal obesity, and combined obesity were 6.90 [3.74-12.70], 2.84 [2.38-3.39], 3.02 [2.02-4.51], and 9.53 [7.79-11.64], respectively. Subgroup analysis showed the effect of different obesity patterns on NAFLD risk was stable among individuals with different clinical conditions. In the fully adjusted multivariate logistic regression model, WC was positively associated with NAFLD risk (OR: 1.48; 95% CI: 1.42-1.53; P < 0.001). WC also demonstrated strong discriminatory ability for NAFLD in Receiver Operating Characteristic (ROC) analysis, achieving an Area Under the Curve (AUC) of 0.802. CONCLUSIONS: Different patterns of obesity are risk factors for NAFLD. An increase in WC significantly increased NAFLD risk. More attention should be paid to preventing different patterns of obesity among adults.


Assuntos
Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Inquéritos Nutricionais , Obesidade , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Masculino , Estudos Transversais , Obesidade/complicações , Obesidade/epidemiologia , Pessoa de Meia-Idade , Adulto , Fatores de Risco , Feminino , Índice de Massa Corporal , Circunferência da Cintura , Estados Unidos/epidemiologia , Obesidade Abdominal/complicações , Obesidade Abdominal/epidemiologia , Obesidade Abdominal/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/epidemiologia , Sobrepeso/complicações , Sobrepeso/epidemiologia
12.
Ther Adv Hematol ; 15: 20406207241257901, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39050114

RESUMO

Children with Down syndrome (DS) are at increased risk of developing haematological malignancies, in particular acute megakaryoblastic leukaemia and acute lymphoblastic leukaemia. The microenvironment established by abnormal haematopoiesis driven by trisomy 21 is compounded by additional genetic and epigenetic changes that can drive leukaemogenesis in patients with DS. GATA-binding protein 1 (GATA1) somatic mutations are implicated in the development of transient abnormal myelopoiesis and the progression to myeloid leukaemia of DS (ML-DS) and provide a model of the multi-step process of leukaemogenesis in DS. This review summarises key genetic drivers for the development of leukaemia in patients with DS, the biology and treatment of ML-DS and DS-associated acute lymphoblastic leukaemia, late effects of treatments for DS-leukaemias and the focus for future targeted therapy.

13.
Adv Sci (Weinh) ; : e2404182, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052878

RESUMO

The switching response in organic electrochemical transistors (OECT) is a basic effect in which a transient current occurs in response to a voltage perturbation. This phenomenon has an important impact on different aspects of the application of OECT, such as the equilibration times, the hysteresis dependence on scan rates, and the synaptic properties for neuromorphic applications. Here we establish a model that unites vertical ion diffusion and horizontal electronic transport for the analysis of the time-dependent current response of OECTs. We use a combination of tools consisting of a physical analytical model; advanced 2D drift-diffusion simulation; and the experimental measurement of a poly(3-hexylthiophene) (P3HT) OECT. We show the reduction of the general model to simple time-dependent equations for the average ionic/hole concentration inside the organic film, which produces a Bernards-Malliaras conservation equation coupled with a diffusion equation. We provide a basic classification of the transient response to a voltage pulse, and the correspondent hysteresis effects of the transfer curves. The shape of transients is basically related to the main control phenomenon, either the vertical diffusion of ions during doping and dedoping, or the equilibration of electronic current along the channel length.

14.
World Neurosurg ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39053852

RESUMO

OBJECTIVE: To develop and validate a clinical-radiomics nomogram for predicting early ischemic stroke risk in patients with transient ischemic attacks (TIA). METHODS: A retrospective training dataset (n=76) and a prospective validation dataset (n=34) of patients with TIA were studied. Image processing was performed using ITK-snap and Artificial Intelligent Kit. Radiomics features selection were done in R. A nomogram predicting recurrent TIA/stroke in 90 days as a recurrent ischemic event was established. The performance of the models was assessed by computing the receiver-operating characteristic and decision curve analysis (DCA). RESULTS: High proportion of diabetes and hypertension in the recurrent than those in the stable patients in both training and validation dataset (P<0.05). Recurrent patients had significant higher ABCD2 score and plaque score than stable patients. ABCD2 score and necrotic/lipid core area were independent risk factors for recurrent ischemic events (OR=2.75, 95% CI: 1.47-6.40; and OR=1.20, 95% CI: 1.07-1.41). The radiomics model had AUC value of 0.737 (95% CI: 0.715-0.878) in training dataset and 0.899 (95% CI: 0.706-0.936) in the validation dataset, which was superior to the ABCD2 score and plaque model for predicting stroke recurrence (P<0.05). The nomogram predicting recurrent ischemic events was 0.923 (95% CI: 0.895-0.978) in the training dataset and 0.935 (95% CI: 0.830-0.959) in the validation dataset. DCA confirmed the clinical value of this nomogram. CONCLUSION: The nomogram, based on clinical ABCD2 score, carotid plaque components and radiomics score, shows good performance in predicting the risk of recurrent ischemic events in TIA.

15.
Radiol Case Rep ; 19(9): 3898-3902, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39040834

RESUMO

Bow Hunter's syndrome (BHS) is an uncommon condition characterized by impingement of one of the two vertebral arteries induced by cervical rotation, causing symptomatic vertebrobasilar insufficiency of the posterior cerebral circulation. We report a case of BHS in an 84-year-old male. Two months following a motor vehicle accident, the patient presented to an urgent care facility with subsequent transfer to the emergency department with complaints of lightheadedness upon right-lateral head movement. A cerebral angiogram demonstrated mild focal stenosis in the dominant left vertebral artery at the C2 level when in neutral position with significant worsening of the stenosis in the right-lateral head position with absent anterograde flow, consistent with BHS. Resultantly, the patient was referred for neurosurgery and successfully underwent placement of right-sided C2-C4 postero-lateral instrumentation and left-sided C2-C3 laminar screws projected towards the right side. This case highlights the importance of imaging in BHS diagnosis and guidance for treatment, as well as the need for a surgical standard of care for BHS patients.

17.
Mol Cell Endocrinol ; 592: 112333, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39048029

RESUMO

Low temperatures significantly influence feeding behavior in ectothermic vertebrates, but the underlying mechanisms remain elusive. This study investigated the role of transient receptor potential ankyrin 1 (TRPA1) channels in mediating the appetite-suppressing effects of low temperature in Nile tilapia. TRPA1 was found to be highly expressed in the hypothalamus and co-localized with neuropeptide Y (NPY) neurons. Exposure to low temperatures reduced feeding frequency and increased TRPA1 expression. In vitro experiments demonstrated that low temperature and TRPA1 agonists induced calcium influx, which was blocked by a TRPA1 inhibitor. TRPA1 expression exhibited post-prandial increases and was downregulated by fasting. TRPA1 activation dose-dependently inhibited food intake, while its inhibition restored feeding suppressed by low temperature. TRPA1 activation downregulated orexigenic factors and upregulated anorexigenic factors through Ca2+/calmodulin-dependent pathways. These findings suggest that TRPA1 plays a crucial role in sensing low temperatures and regulating feeding behavior in tilapia.

18.
Nano Lett ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056490

RESUMO

Using heterodyne transient grating spectroscopy, we observe a significant enhancement of exciton diffusion in a monolayer WSe2 stacked on graphene. The diffusion dynamics can be optically tuned within a few picoseconds by altering the photoexcited carrier density in graphene. The effective diffusion constant in initial picoseconds in the WSe2/graphene heterostructure is (40.3 ± 4.5) cm2 s-1, representing a substantial improvement over (2.1 ± 0.8) cm2 s-1, typical for an isolated WSe2 monolayer. This enhancement can be understood in terms of a transient screening of impurities, charge traps, and defect states in WSe2 by photoexcited charge carriers in graphene. Furthermore, diffusion within WSe2 is affected by interlayer interactions, such as charge transfer, varying with the incident excitation fluence. These findings underscore the dynamical nature of screening and diffusion processes in heterostructures of 2D semiconductors and graphene and provide insights for future applications of these systems in ultrafast optoelectronic devices.

19.
Hematol Rep ; 16(3): 431-439, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39051415

RESUMO

Transient stress lymphocytosis (TSL) is an under-recognized phenomenon associated with an acute stressful event such as physical trauma or various emergency medical conditions. Lymphocytosis generally resolves within several hours to days of the stressor. While most reports of TSL predominantly involve adult patients, it has only rarely been reported in pediatric patients. Here, we describe the clinical course of a 9-year-old male who developed TSL following a traumatic fall from a second-story balcony and provide a systematic literature review of TSL.

20.
Entropy (Basel) ; 26(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39056914

RESUMO

The intricate relationship between electrons and the crystal lattice is a linchpin in condensed matter, traditionally described by the Fröhlich model encompassing the lowest-order lattice-electron coupling. Recently developed quantum acoustics, emphasizing the wave nature of lattice vibrations, has enabled the exploration of previously uncharted territories of electron-lattice interaction not accessible with conventional tools such as perturbation theory. In this context, our agenda here is two-fold. First, we showcase the application of machine learning methods to categorize various interaction regimes within the subtle interplay of electrons and the dynamical lattice landscape. Second, we shed light on a nebulous region of electron dynamics identified by the machine learning approach and then attribute it to transient localization, where strong lattice vibrations result in a momentary Anderson prison for electronic wavepackets, which are later released by the evolution of the lattice. Overall, our research illuminates the spectrum of dynamics within the Fröhlich model, such as transient localization, which has been suggested as a pivotal factor contributing to the mysteries surrounding strange metals. Furthermore, this paves the way for utilizing time-dependent perspectives in machine learning techniques for designing materials with tailored electron-lattice properties.

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