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1.
Biomed Eng Lett ; 14(4): 891-902, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38946808

RESUMEN

Highly complex cognitive works require more brain power. The productivity of a person suffers due to this strain, which is sometimes referred to as a mental burden or psychological load. A person's mental health and safety in high-stress working conditions can be improved with the help of mental workload assessment. A photoplethysmogram (PPG) signal is a non-invasive and easily acquired physiological signal that contains information related to blood volume changes in the micro-vascular bed of tissues and can indicate psychologically relevant information to assess a person's mental workload (MW). An individual under a high MW possesses an increase in sympathetic nervous system activity, which results in morphological changes in the PPG waveform. In this work, a time-frequency analysis framework is developed to capture these distinguishing PPG features for the automatic assessment of MW. In particular, a cross-wavelet coherence (WTC) approach is proposed to extract simultaneous time-frequency information of the PPG during MW relative to the resting PPG. The suggested technique is validated on a publicly available data set of 22 healthy individuals who took part in an N-back task with PPG recording. Under three different fixed window lengths, images are obtained using WTC between PPG records during N-back task activity and rest. The images are used further to obtain PPG classification in two broad classes of low and high MW using a customized pre-trained Inception-V3 model. The best validation and test accuracy of 93.86% and 93.07%, respectively obtained in the window setting of 1200 samples used for WTC image creation.

2.
Int Cancer Conf J ; 13(3): 184-188, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38962055

RESUMEN

Solid tumors harboring mutations in the Braf gene (BRAF) are currently treated by combination Braf/MEK inhibitor therapy, and there is an extensive literature on patient response rates. Alternatively, few studies have documented the clinical response of BRAF mutation-positive solid tumors to MEK inhibitor monotherapy. We report the case of a 57-year-old female diagnosed with papillary thyroid carcinoma and progressive lung metastases initially treated by total thyroidectomy and subsequent thyroid-stimulating hormone suppression therapy. Next-generation sequencing revealed that the tumor harbored a BRAF V600E mutation, and the patient was enrolled in a clinical study of the oral MEK1/2 inhibitor binimetinib. Shortly after starting treatment, the patient experienced pneumothorax due to rapid regression of lung metastases, and computed tomography after 6 months of binimetinib treatment revealed a partial sustained response. One year later, the dose was reduced because of an acneiform rash. After 5 years of binimetinib treatment, lung metastases had regrown, and treatment was switched to the oral multikinase inhibitor lenvatinib. This case demonstrates the potential of MEK inhibitor monotherapy as an alternative treatment for BRAF mutation-positive papillary thyroid carcinoma.

3.
J Colloid Interface Sci ; 675: 379-390, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38972125

RESUMEN

Nowadays, the inherent re-stacking nature and weak d-p hybridization orbital interactions within MXene remains significant challenges in the field of electrocatalytic water splitting, leading to unsatisfactory electrocatalytic activity and cycling stability. Herein, this work aims to address these challenges and improve electrocatalytic performance by utilizing cobalt nanoparticles intercalation coupled with enhanced π-donation effect. Specifically, cobalt nanoparticles are integrated into V2C MXene nanosheets to mitigate the re-stacking issue. Meanwhile, a notable charge redistribution from cobalt to vanadium elevates orbital levels, reduces π*-antibonding orbital occupancy and alleviates Jahn-Teller distortion. Doping with tellurium induces localized electric field rearrangement resulting from the changes in electron cloud density. As a result, Co-V2C MXene-Te acquires desirable activity for hydrogen evolution reaction and oxygen evolution reaction with the overpotential of 80.8 mV and 287.7 mV, respectively, at the current density of -10 mA cm-2 and 10 mA cm-2. The overall water splitting device achieves an impressive low cell voltage requirement of 1.51 V to obtain 10 mA cm-2. Overall, this work could offer a promising solution when facing the re-stacking issue and weak d-p hybridization orbital interactions of MXene, furnishing a high-performance electrocatalyst with favorable electrocatalytic activity and cycling stability.

4.
Front Plant Sci ; 15: 1401525, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38966140

RESUMEN

Powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) seriously threatens wheat production worldwide. It is imperative to identify novel resistance genes from wheat and its wild relatives to control this disease by host resistance. Dasypyrum villosum (2n = 2x = 14, VV) is a relative of wheat and harbors novel genes for resistance against multi-fungal diseases. In the present study, we developed a complete set of new wheat-D. villosum disomic introgression lines through genomic in situ hybridization (GISH), fluorescence in situ hybridization (FISH) and molecular markers analysis, including four disomic substitution lines (2n=42) containing respectively chromosomes 1V#6, 2V#6, 3V#6, and 6V#6, and four disomic addition lines (2n=44) containing respectively chromosomes 4V#6, 5V#6, 6V#6 and 7V#6. These lines were subsequently evaluated for their responses to a mixture Bgt isolates at both seedling and adult-plant stages. Results showed that introgression lines containing chromosomes 3V#6, 5V#6, and 6V#6 exhibited resistance at both seedling and adult-plant stages, whereas the chromosome 4V#6 disomic addition line NAU4V#6-1 exhibited a high level of adult plant resistance to powdery mildew. Moreover, two translocation lines were further developed from the progenies of NAU4V#6-1 and the Ph1b mutation line NAU0686-ph1b. They were T4DL·4V#6S whole-arm translocation line NAU4V#6-2 and T7DL·7DS-4V#6L small-fragment translocation line NAU4V#6-3. Powdery mildew tests of the two lines confirmed the presence of an adult-plant powdery mildew resistance gene, Pm4VL, located on the terminal segment of chromosome arm 4V#6L (FL 0.6-1.00). In comparison with the recurrent parent NAU0686 plants, the T7DL·7DS-4V#6L translocation line NAU4V#6-3 showed no obvious negative effect on yield-related traits, providing a new germplasm in breeding for resistance.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38966498

RESUMEN

Patients with cancer are at risk for thrombotic complications due to a hypercoagulable state. However, the benefit of prophylactic anticoagulation is unclear in many subsets of these patients. For the first episode of acute thromboembolic disease (VTE) in patients with active cancer, anticoagulant therapy is administered for at least three to six months. Herein, we present a 31-year-old female with active, recurrent stage IIIa classical Hodgkin lymphoma (CHL) (nodular sclerosis), previously treated for proximal upper extremity deep vein thrombosis (DVT), presenting for evaluation of shortness of breath and eventually diagnosed with bilateral pulmonary embolism (PE) secondary to a right atrial thrombus. The patient was successfully treated with surgical resection of the thrombus. With this case report, we hope to encourage physicians to use prophylactic indefinite anticoagulation in patients with active cancer and previous DVT, including patients with upper extremity DVT.

6.
J Thromb Haemost ; 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38950780

RESUMEN

BACKGROUND: ; Factor (F)V is pivotal in both procoagulant and anticoagulant mechanisms. The present report describes a novel F5 mutation in a FV-deficient patient (FV:C 6 IU/dL, FV:Ag 32 IU/dL), complicated with recurrent deep vein thrombosis. The patient demonstrated activated protein C resistance (APCR) with compound heterozygous mutations consisting of FV-Y1961C (FVKanazawa) and FV-1982_1983del. AIM;: To clarify thrombotic mechanisms associated with this FV abnormality. METHODS AND RESULTS: Levels of FV-1982_1983del were below the detection sensitivity in our expression experiments using HEK293T cells, and analyses were targeted, therefore on the FV-Y1961C mutation. APTT-based clotting assays demonstrated that FV-Y1961C exhibited APCR, and that the reduced APC susceptibility in FVa-Y1961C resulted in a marked depression of APC-catalyzed inactivation with delayed cleavage at Arg506 and little cleavage at Arg306 with or without protein (P)S. The APC cofactor activity of FV-Y1961C in APC-catalyzed FVIIIa inactivation promoted by Arg336 cleavage in FVIII was impaired. The binding affinity of FVa-Y1961C to phospholipid membranes was reduced in reactions involving APC/PS-catalyzed inactivation and in prothrombinase activity. Furthermore, the addition of FVa-Y1961C to plasma failed to inhibit tissue factor (TF)-induced procoagulant function. These characteristics were similar to those of FV-W1920R (FVNara) and FV-A2086D (FVBesançon). CONCLUSIONS: ; We identified a compound heterozygous. FV-Y1961C mutation in the C1 domain representing a novel FV mutation (FVKanazawa) resulting in not only APCR due to impaired FVa susceptibility and FV cofactor activity for APC function, but impaired inhibition of TF-induced procoagulant function. These defects in anticoagulant function associated with FV in FV-Y1961C contributed to a prothrombotic state.

7.
Cell Signal ; : 111273, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38950874

RESUMEN

Diabetes-associated periodontitis (DP) presents severe inflammation and resistance to periodontal conventional treatment, presenting a significant challenge in clinical management. In this study, we investigated the underlying mechanism driving the hyperinflammatory response in gingival epithelial cells (GECs) of DP patients. Our findings indicate that lysosomal dysfunction under high glucose conditions leads to the blockage of autophagy flux, exacerbating inflammatory response in GECs. Single-cell RNA sequencing and immunohistochemistry analyses of clinical gingival epithelia revealed dysregulation in the lysosome pathway characterized by reduced levels of lysosome-associated membrane glycoprotein 2 (LAMP2) and V-type proton ATPase 16 kDa proteolipid subunit c (ATP6V0C) in subjects with DP. In vitro stimulation of human gingival epithelial cells (HGECs) with a hyperglycemic microenvironment showed elevated release of proinflammatory cytokines, compromised lysosomal acidity and blocked autophagy. Moreover, HGECs with deficiency in ATP6V0C demonstrated impaired autophagy and heightened inflammatory response, mirroring the effects of high glucose stimulation. Proteomic analysis of acetylation modifications identified altered acetylation levels in 28 autophagy-lysosome pathway-related proteins and 37 sites in HGECs subjected to high glucose stimulation or siATP6V0C. Overall, our finding highlights the pivotal role of lysosome impairment in autophagy obstruction in DP and suggests a potential impact of altered acetylation of relevant proteins on the interplay between lysosome dysfunction and autophagy blockage. These insights may pave the way for the development of effective therapeutic strategies against DP.

8.
Int J Hematol ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951434

RESUMEN

Polycythemia vera (PV) is a Philadelphia chromosome-negative myeloproliferative neoplasm characterized by clonal erythrocytosis. A phase 2 study reported that ropeginterferon alfa-2b is a well-tolerated and effective treatment for PV in Japanese patients. This post hoc analysis of the phase 2 data further evaluated outcomes in patients at low risk of thrombosis (low-risk PV). Among 20 patients with low-risk PV, 60.0% (12/20) and 85.0% (17/20) achieved < 45% hematocrit by weeks 24 and 52, respectively. The proportion of responders with complete hematologic response (CHR) was 60.0% (12/20) at week 52, and the median time to response was 11.9 months. The mean JAK2 V617F allele burden decreased from 75.8% at baseline to 53.7% at week 52. No patient experienced thrombosis or bleeding episodes. All patients experienced treatment-emergent adverse events (TEAEs) related to ropeginterferon alfa-2b, but no grade ≥ 3 TEAEs or deaths related to ropeginterferon alfa-2b occurred, and no new safety concerns arose. This analysis indicated that ropeginterferon alfa-2b may be an effective treatment option for Japanese patients with low-risk PV.

9.
Artículo en Inglés | MEDLINE | ID: mdl-38963460

RESUMEN

PURPOSE: Abnormalities in lipid metabolism have been proposed in Bietti's crystalline dystrophy (BCD). We aim to characterize the lipid profiles in a case-control study. METHODS: All participants were genetically confirmed by CYP4V2 gene sequencing and underwent chorioretinopathy evaluation by calculating the percentages of AF atrophy (PAFA). Fasting blood samples of BCD patients and controls were collected, and plasma was analyzed for routine lipid profiles. Targeted lipidomic evaluation includes long chain polyunsaturated fatty acids (LCPUFA) and associated eicosanoid metabolites. RESULTS: Routine lipids profiles showed elevated plasma levels of triglyceride (P = 0.043) and low-density lipoprotein cholesterol (P = 0.024) in BCD patients. Lipidomic analysis showed significantly decreased levels of ω-3 LCPUFA including docosahexaenoic acid (DHA, 22:6, P = 0.00068) and eicosapentaenoic acid (EPA, 20:5, P = 0.0016), as well as ω-6 LCPUFA arachidonic acid (ARA, 20:4, P < 0.0001) in BCD patients. Eicosanoid metabolites, either derived from ω-3 and/ or ω-6 LCPUFAs via cyclooxygenase (COX) or lipoxygenase (LOX) pathways, including 5-HEPE, 12-HEPE, 13-HDHA, 15-HETE, 12-HETE, 5-HETE, 6k-PGF1a, PGE2, PGJ2, and TXB2, exhibited significant differences (P < 0.0001) between BCD patients and controls. Genotypes of CYP4V2, specifically the biallelic null mutations, were observed to correlate with more remarkably reduced levels of oxylipins, involving major LOX pathway metabolites including 5-HETE, 5-HEPE, 12-HEPE and LTB4. CONCLUSIONS: BCD patients demonstrated significant decreases in plasma levels of ω-3 and ω-6 LCPUFA (DHA, EPA, and ARA), as well as their downstream metabolites via the COX and LOX pathways, suggesting that these might be implicated in BCD pathogenesis and could serve as biomarkers and therapeutic targets of the disease. KEY MESSAGES: What is known BCD is a vision-threatening hereditary disease the causative gene of which is CYP4V2. Abnormalities in lipid metabolism have been proposed and demonstrated previously in BCD studies. The detailed pathogenesis remains unclear and controversial. What is new We observed prominent lipidomic alterations in the circulation when compared with age, gender, and bodymass index (BMI)-matched healthy controls. BCD patients demonstrated significant decreases in plasma levels of ω-3 and ω-6 LCPUFA (DHA, EPA, and ARA). Remarkable changes were observed in the downstream metabolites of the LCPUFA via the COX and LOX pathways. Genotypes of CYP4V2, specifically the biallelic null mutations, were observed to correlate with more remarkably reduced levels of oxylipins, involving major LOX pathway metabolites.

10.
Subcell Biochem ; 104: 409-423, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38963494

RESUMEN

The hemostatic response to vascular injury entails a sequence of proteolytic events where several inactive zymogens of the trypsin family are converted to active proteases. The cascade starts with exposure of tissue factor from the damaged endothelium and culminates with conversion of prothrombin to thrombin in a reaction catalyzed by the prothrombinase complex composed of the enzyme factor Xa, cofactor Va, Ca2+, and phospholipids. This cofactor-dependent activation is paradigmatic of analogous reactions of the blood coagulation and complement cascades, which makes elucidation of its molecular mechanism of broad significance to the large class of trypsin-like zymogens to which prothrombin belongs. Because of its relevance as the most important reaction in the physiological response to vascular injury, as well as the main trigger of pathological thrombotic complications, the mechanism of prothrombin activation has been studied extensively. However, a molecular interpretation of this mechanism has become available only recently from important developments in structural biology. Here we review current knowledge on the prothrombin-prothrombinase interaction and outline future directions for the study of this key reaction of the coagulation cascade.


Asunto(s)
Coagulación Sanguínea , Protrombina , Tromboplastina , Humanos , Protrombina/metabolismo , Protrombina/química , Tromboplastina/metabolismo , Tromboplastina/química , Coagulación Sanguínea/fisiología , Animales , Unión Proteica , Factor Xa/metabolismo , Factor V
11.
Egypt Heart J ; 76(1): 82, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963552

RESUMEN

BACKGROUND: Anxiety and depression are potentially harmful outcomes of permanent cardiac pacemakers. Dual-chamber P.P.M. is frequently used to treat life threatening bradycardia. The study aims to estimate the effect of the right ventricular PM lead position on recipients' anxiety and depression before, 6 months, and 1 year after implantation. RESULTS: A statistically significant correlation was discovered between the studied groups regarding HADS depression score after 6 months (p 0.013) and 1 year (p 0.013). A statistically non-significant difference was found among the studied groups at any point of time regarding baseline (p 0.063), after 6 months (p 0.054), or after 1 year (p 0.099). Significance was found between HADS anxiety score (p 0.015) or depression score after 1 year and the incidence of complications (p 0.001). CONCLUSIONS: A strong relationship was found between the level of depression and the R.V. site of implantation, as patients with the apical group had higher levels of depression post-implantation. The septal position has less stress and depression on the patient's well-being than the apical one.

12.
Scand J Med Sci Sports ; 34(7): e14691, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38970442

RESUMEN

Quantifying movement coordination in cross-country (XC) skiing, specifically the technique with its elemental forms, is challenging. Particularly, this applies when trying to establish a bidirectional transfer between scientific theory and practical experts' knowledge as expressed, for example, in ski instruction curricula. The objective of this study was to translate 14 curricula-informed distinct elements of the V2 ski-skating technique (horizontal and vertical posture, lateral tilt, head position, upper body rotation, arm swing, shoulder abduction, elbow flexion, hand and leg distance, plantar flexion, ski set-down, leg push-off, and gliding phase) into plausible, valid and applicable measures to make the technique training process more quantifiable and scientifically grounded. Inertial measurement unit (IMU) data of 10 highly experienced XC skiers who demonstrated the technique elements by two extreme forms each (e.g., anterior versus posterior positioning for the horizontal posture) were recorded. Element-specific principal component analyses (PCAs)-driven by the variance produced by the technique extremes-resulted in movement components that express quantifiable measures of the underlying technique elements. Ten measures were found to be sensitive in distinguishing between the inputted extreme variations using statistical parametric mapping (SPM), whereas for four elements the SPM did not detect differences (lateral tilt, plantar flexion, ski set-down, and leg push-off). Applicability of the established technique measures was determined based on quantifying individual techniques through them. The study introduces a novel approach to quantitatively assess V2 ski-skating technique, which might help to enhance technique feedback and bridge the communication gap that often exists between practitioners and scientists.


Asunto(s)
Postura , Análisis de Componente Principal , Esquí , Esquí/fisiología , Humanos , Masculino , Postura/fisiología , Fenómenos Biomecánicos , Adulto , Movimiento/fisiología , Femenino , Adulto Joven , Brazo/fisiología , Hombro/fisiología , Rotación
13.
Cell Mol Life Sci ; 81(1): 286, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970652

RESUMEN

Paralog factors are considered to ensure the robustness of biological processes by providing redundant activity in cells where they are co-expressed. However, the specific contribution of each factor is frequently underestimated. In the developing spinal cord, multiple families of transcription factors successively contribute to differentiate an initially homogenous population of neural progenitors into a myriad of neuronal subsets with distinct molecular, morphological, and functional characteristics. The LIM-homeodomain transcription factors Lhx3, Lhx4, Isl1 and Isl2 promote the segregation and differentiation of spinal motor neurons and V2 interneurons. Based on their high sequence identity and their similar distribution, the Lhx3 and Lhx4 paralogs are considered to contribute similarly to these processes. However, the specific contribution of Lhx4 has never been studied. Here, we provide evidence that Lhx3 and Lhx4 are present in the same cell populations during spinal cord development. Similarly to Lhx3, Lhx4 can form multiproteic complexes with Isl1 or Isl2 and the nuclear LIM interactor NLI. Lhx4 can stimulate a V2-specific enhancer more efficiently than Lhx3 and surpasses Lhx3 in promoting the differentiation of V2a interneurons in chicken embryo electroporation experiments. Finally, Lhx4 inactivation in mice results in alterations of differentiation of the V2a subpopulation, but not of motor neuron production, suggesting that Lhx4 plays unique roles in V2a differentiation that are not compensated by the presence of Lhx3. Thus, Lhx4 could be the major LIM-HD factor involved in V2a interneuron differentiation during spinal cord development and should be considered for in vitro differentiation of spinal neuronal populations.


Asunto(s)
Diferenciación Celular , Interneuronas , Proteínas con Homeodominio LIM , Médula Espinal , Factores de Transcripción , Animales , Proteínas con Homeodominio LIM/metabolismo , Proteínas con Homeodominio LIM/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Interneuronas/metabolismo , Interneuronas/citología , Médula Espinal/citología , Médula Espinal/metabolismo , Médula Espinal/embriología , Embrión de Pollo , Ratones , Neuronas Motoras/metabolismo , Neuronas Motoras/citología , Humanos , Regulación del Desarrollo de la Expresión Génica
14.
Lung Cancer ; 194: 107869, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38970909

RESUMEN

Osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), is routinely prescribed as first-line therapy for advanced non-small cell lung cancer, regardless of the presence of the T790M resistance mutation. This study reports a rare case of Factor V inhibitor detection during osimertinib therapy in a patient with lung adenocarcinoma. These findings underscore the importance of vigilant monitoring for coagulation abnormalities during EGFR-TKI therapy.

15.
Adv Exp Med Biol ; 1445: 37-46, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38967748

RESUMEN

It is widely acknowledged that immunoglobulins (Igs) are produced solely by B-lineage cells. The Ig gene is created by the rearrangement of a group of gene segments [variable (V), diversity (D), and joining (J) segments rearrangement, or V(D)J recombination], which results in the vast diversity of B cell-derived Ig responsible for recognising various antigens. Ig subsequently undergoes somatic hypermutation (SHM) and class switch recombination (CSR) after exposure to antigens, thus converting the low-affinity IgM to IgG, IgA, or IgE antibodies. IgM and IgD are primarily expressed in naïve B cells that have not been exposed to antigens, they do not undergo somatic hypermutation; hence, their variable region sequences remain the same as those in the germline. In contrast, IgG, IgA, and IgE are expressed in antigen-stimulated memory B cells or plasma cells, and thus, they often possess high-frequency mutations in their variable region sequences. Since the discovery that Ig can be produced by non-B cells, Qiu's group has investigated and compared the genetic characteristics of B cell-derived Ig and non-B cell-derived Ig. These findings demonstrated that non-B cell-derived Ig shares certain similarities with B cell-derived Ig in that the sequence of its constant region is identical to that of B cell-derived Ig, and its variable region is also strictly dependent on the rearrangement of V, D, and J gene segments. Moreover, akin to B cell-derived Ig, the V regions of IgM and IgD are rarely mutated, while IgG, IgA, and IgE produced by cancer cells are frequently mutated. However, the non-B cell-derived Ig V region sequence displays unique characteristics. (1) Unlike the vast diversity of B cell-derived Igs, non-B cell-derived Igs exhibit restricted diversity; cells from the same lineage always select the same V(D)J recombination patterns; (2) Both mRNA and proteins of RAG1/RAG2 recombinase have been detected in Ig positive cancer cell lines and normal tissues. But Ig recombination could also be found in RAG1-/- and RAG2-/- mice, suggesting that they are not necessary for the rearrangement of non-B cell-derived Igs. These features of non-B cell-derived Igs suggest a potentially undiscovered mechanism of V(D)J recombination, ligation, and SHM in non-B cells, which necessitates further investigation with advanced technology in molecular biology.


Asunto(s)
Linfocitos B , Genes de Inmunoglobulinas , Animales , Humanos , Ratones , Linfocitos B/inmunología , Genes de Inmunoglobulinas/genética , Cambio de Clase de Inmunoglobulina/genética , Cambio de Clase de Inmunoglobulina/inmunología , Inmunoglobulinas/genética , Inmunoglobulinas/inmunología , Hipermutación Somática de Inmunoglobulina/genética
16.
Prog Neurobiol ; 240: 102655, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38969016

RESUMEN

Object recognition often involves the brain segregating objects from their surroundings. Neurophysiological studies of figure-ground texture segregation have yielded inconsistent results, particularly on whether V1 neurons can perform figure-ground texture segregation or just detect texture borders. To address this issue from a population perspective, we utilized two-photon calcium imaging to simultaneously record the responses of large samples of V1 and V4 neurons to figure-ground texture stimuli in awake, fixating macaques. The average response changes indicate that V1 neurons mainly detect texture borders, while V4 neurons are involved in figure-ground segregation. However, population analysis (SVM decoding of PCA-transformed neuronal responses) reveal that V1 neurons not only detect figure-ground borders, but also contribute to figure-ground texture segregation, although requiring substantially more principal components than V4 neurons to reach a 75 % decoding accuracy. Individually, V1/V4 neurons showing larger (negative/positive) figure-ground response differences contribute more to figure-ground segregation. But for V1 neurons, the contribution becomes significant only when many principal components are considered. We conclude that V1 neurons participate in figure-ground segregation primarily by defining the figure borders, and the poorly structured figure-ground information V1 neurons carry could be further utilized by V4 neurons to accomplish figure-ground segregation.

17.
MethodsX ; 12: 102783, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38966713

RESUMEN

In recent years, frequent and substantial area-wide power outages have underscored the critical need for cities to possess robust backup power sources capable of swift response to prevent prolonged power system disruptions. Electric vehicles can contribute electricity to the power grid using vehicle-to-grid technology. The power delivered by electric vehicles in this context is termed as response capability. However, existing studies have overlooked response capability dynamics during transitions between electric vehicle states-such as the shift from charging or discharging to an idle state, thereby hindering a comprehensive understanding of this aspect. Hence, this paper introduces a multi-timescale response capability prediction model that evaluates the electric vehicle's state of charge to ensure users' requirements are met for upcoming trips. To better assess users' travel demand, the gravity model is employed as a precursor to response capability prediction to further enhance the validity of the prediction outcomes. Three neighborhoods in Los Angeles have been chosen for analysis: Downtown, Lincoln Heights, and Silver Lake. Predictions indicate that neglecting the response capability when electric vehicles undergo state transformation can lead to a differential response capability ranging from 2000 kWh to 4000 kWh, resulting in a loss of prediction accuracy by 20 % to 25 %.•The response capability of EV is non-zero during state transformations•Users' travel demand assessment•Seamless integration of vehicle-to-grid technology into the power grid.

18.
Front Bioeng Biotechnol ; 12: 1371693, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38978718

RESUMEN

Introduction: Titanium-based implants can be used to fill voids in bone reconstruction surgery. Through additive manufacturing (AM), it is possible to produce titanium implants with osteoconductive properties such as high porosity and low stiffness. AM facilitates a level of design flexibility and personalization that is not feasible with traditional techniques. Methods: In this study, osseointegration into titanium alloy (Ti-6Al-4V) lattices was investigated for 12 weeks post-implantation using a novel bicortical load-bearing ovine model. The objective was to assess the safety and efficacy of AM-fabricated implants using two lattice structures of contrasting stiffness spanning the full width of the femoral condyle. Results: This was achieved by evaluating implant osseointegration and bone-implant contact properties by histomorphometry, scoring local implant tissue responses via histopathology, and micro-computed tomography reconstruction. Discussion: We found that Ti-6Al-4V implants facilitated widespread and extensive osseointegration, with bone maturation ongoing at the conclusion of the trial period. Following the implantation period, no adverse clinical indications that could be directly ascribed to the presence of the implanted device were identified, as determined by macroscopic and microscopic observation.

19.
Cureus ; 16(6): e61973, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38978936

RESUMEN

We present the case of a 36-year-old female with Factor V Leiden mutation taking warfarin, who presented to the emergency department with swelling in the abdominal and bilateral lower extremities. Initial assessment revealed an international normalized ratio (INR) of 5.0. Abdomen/pelvis computed tomography (CT) and computed tomographic angiography (CTA) scans indicated chronic thrombosis of the inferior vena cava (IVC), leading to the development of ascites and swelling. Extensive investigations were conducted to explore potential contributing factors for the ascites and edema, all of which yielded negative results. Warfarin was discontinued, and unfractionated heparin was initiated once the INR decreased to 2.0. The patient underwent IVC angioplasty with stent placement, resulting in significant improvement of ascites and lower extremity swelling. Subsequently, heparin was transitioned to oral warfarin, and therapeutic INR levels were achieved before discharge. At the follow-up outpatient visit, the patient's ascites and lower extremity edema had completely resolved. This case highlights a rare instance of IVC involvement associated with Factor V Leiden mutation. Furthermore, the patient's history of noncompliance with medication, initial supratherapeutic INR, and chronic IVC thrombosis emphasize the importance of medication adherence and the crucial role of primary care in ensuring regular follow-up and monitoring.

20.
Clin Kidney J ; 17(7): sfae163, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38979109

RESUMEN

Background: Patients with kidney failure treated with maintenance haemodialysis (HD) require appropriate small molecule clearance. Historically, a component of measuring 'dialysis adequacy' has been quantified using urea kinetic modelling that is dependent on the HD prescription. However, the impact of dialysate flow rate on urea clearance remains poorly described in vivo and its influence on other patient-important outcomes of adequacy is uncertain. Methods: We searched Embase, MEDLINE and the Cochrane Library from inception until April 2022 for randomized controlled trials and observational trials comparing a higher dialysate flow rate (800 ml/min) and lower dialysate flow rate (300 ml/min) with a standard dialysis flow rate (500 ml/min) in adults (age ≥18 years) treated with maintenance HD (>90 consecutive days). We conducted a random effects meta-analysis to estimate the pooled mean difference in dialysis adequacy as measured by Kt/V or urea reduction ratio (URR). Results: A total of 3118 studies were identified. Of those, nine met eligibility criteria and four were included in the meta-analysis. A higher dialysate flow rate (800 ml/min) increased single-pool Kt/V by 0.08 [95% confidence interval (CI) 0.05-0.10, P < .00001] and URR by 3.38 (95% CI 1.97-4.78, P < .00001) compared with a dialysate flow rate of 500 ml/min. Clinically relevant outcomes including symptoms, cognition, physical function and mortality were lacking and studies were generally at a moderate risk of bias due to issues with randomization sequence generation, allocation concealment and blinding. Conclusion: A higher dialysate flow increased urea-based markers of dialysis adequacy. Additional high-quality research is needed to determine the clinical, economic and environmental impacts of higher dialysate flow rates.

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