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1.
Proc Natl Acad Sci U S A ; 120(2): e2215509119, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36608295

RESUMEN

Recently, Co-based honeycomb magnets have been proposed as promising candidate materials to host the Kitaev spin liquid (KSL) state. One of the front-runners is BaCo2(AsO4)2 (BCAO), where it was suggested that the exchange processes between Co2+ ions via the surrounding edge-sharing oxygen octahedra could give rise to bond-dependent Kitaev interactions. In this work, we present and analyze a comprehensive inelastic neutron scattering (INS) study of BCAO with fields in the honeycomb plane. Combining the constraints from the magnon excitations in the high-field polarized state and the inelastic spin structure factor measured in zero magnetic field, we examine two leading theoretical models: the Kitaev-type [Formula: see text] model and the XXZ[Formula: see text]model. We show that the existing experimental data can be consistently accounted for by the XXZ[Formula: see text]model but not by the [Formula: see text] model, and we discuss the implications of these results for the realization of a spin liquid phase in BCAO and more generally for the realization of the Kitaev model in cobaltates.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38771147

RESUMEN

Alteration in the normal mechanical forces of breathing can contribute to changes in contractility and remodeling characteristic of airway diseases, but the mechanisms that mediate these effects in airway cells are still under investigation. Airway smooth muscle (ASM) cells contribute to both contractility and extracellular matrix (ECM) remodeling. In this study, we explored ASM mechanisms activated by mechanical stretch, focusing on mechanosensitive piezo channels and the key Ca2+ regulatory protein stromal interaction molecule 1 (STIM1). Expression of Ca2+ regulatory proteins, including STIM1, Orai1 and caveolin-1, mechanosensitive ion channels Piezo-1 and Piezo-2, and NLRP3 inflammasomes were upregulated by 10% static stretch superimposed on 5% cyclic stretch. These effects were blunted by STIM1 siRNA. Histamine-induced [Ca2+]i responses and inflammasome activation were similarly blunted by STIM1 knockdown. These data show that the effects of mechanical stretch in human ASM cells are mediated through STIM1, which activates multiple pathways including Piezo channels and the inflammasome, leading to potential downstream changes in contractility and ECM remodeling.

3.
J Child Psychol Psychiatry ; 65(7): 932-941, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38098445

RESUMEN

BACKGROUND: Cross sectional studies have identified linguistic correlates of major depressive disorder (MDD) in smartphone communication. However, it is unclear whether monitoring these linguistic characteristics can detect when an individual is experiencing MDD, which would facilitate timely intervention. METHODS: Approximately 1.2 million messages typed into smartphone social communication apps (e.g. texting, social media) were passively collected from 90 adolescents with a range of depression severity over a 12-month period. Sentiment (i.e. positive vs. negative valence of text), proportions of first-person singular pronouns (e.g. 'I'), and proportions of absolutist words (e.g. 'all') were computed for each message and converted to weekly aggregates temporally aligned with weekly MDD statuses obtained from retrospective interviews. Idiographic, multilevel logistic regression models tested whether within-person deviations in these linguistic features were associated with the probability of concurrently meeting threshold for MDD. RESULTS: Using more first-person singular pronouns in smartphone communication relative to one's own average was associated with higher odds of meeting threshold for MDD in the concurrent week (OR = 1.29; p = .007). Sentiment (OR = 1.07; p = .54) and use of absolutist words (OR = 0.99; p = .90) were not related to weekly MDD. CONCLUSIONS: Passively monitoring use of first-person singular pronouns in adolescents' smartphone communication may help detect MDD, providing novel opportunities for early intervention.


Asunto(s)
Trastorno Depresivo Mayor , Teléfono Inteligente , Humanos , Adolescente , Trastorno Depresivo Mayor/diagnóstico , Femenino , Masculino , Lingüística , Aplicaciones Móviles
4.
Psychophysiology ; 61(4): e14476, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37905333

RESUMEN

The ability to accurately identify and interpret others' emotions is critical for social and emotional functioning during adolescence. Indeed, previous research has identified that laboratory-based indices of facial emotion recognition and engagement with emotional faces predict adolescent mood states. Whether socioemotional information processing relates to real-world affective dynamics using an ecologically sensitive approach, however, has rarely been assessed. In the present study, adolescents (N = 62; ages 13-18) completed a Facial Recognition Task, including happy, angry, and sad stimuli, while EEG data were acquired. Participants also provided ecological momentary assessment (EMA) data probing their current level of happiness, anger, and sadness for 1-week, resulting in indices of emotion (mean-level, inertia, instability). Analyses focused on relations between (1) accuracy for and (2) prolonged engagement with (LPP) emotional faces and EMA-reported emotions. Greater prolonged engagement with happy faces was related to less resistance to changes in happiness (i.e., less happiness inertia), whereas greater prolonged engagement with angry faces associated with more resistance to changes in anger (i.e., greater anger inertia). Results suggest that socioemotional processes captured by laboratory measures have real-world implications for adolescent affective states and highlight potentially actionable targets for novel treatment approaches (e.g., just-in-time interventions). Future studies should continue to assess relations among socioemotional informational processes and dynamic fluctuations in adolescent affective states.


Asunto(s)
Emociones , Reconocimiento Facial , Adolescente , Humanos , Emociones/fisiología , Ira/fisiología , Felicidad , Tristeza , Reconocimiento Facial/fisiología , Expresión Facial
5.
Artículo en Inglés | MEDLINE | ID: mdl-38836996

RESUMEN

PURPOSE OF REVIEW: This review provides an overview of the current and future role of artificial intelligence (AI) and virtual reality (VR) in addressing the complexities inherent to the diagnosis, classification, and management of headache disorders. RECENT FINDINGS: Through machine learning and natural language processing approaches, AI offers unprecedented opportunities to identify patterns within complex and voluminous datasets, including brain imaging data. This technology has demonstrated promise in optimizing diagnostic approaches to headache disorders and automating their classification, an attribute particularly beneficial for non-specialist providers. Furthermore, AI can enhance headache disorder management by enabling the forecasting of acute events of interest, such as migraine headaches or medication overuse, and by guiding treatment selection based on insights from predictive modeling. Additionally, AI may facilitate the streamlining of treatment efficacy monitoring and enable the automation of real-time treatment parameter adjustments. VR technology, on the other hand, offers controllable and immersive experiences, thus providing a unique avenue for the investigation of the sensory-perceptual symptomatology associated with certain headache disorders. Moreover, recent studies suggest that VR, combined with biofeedback, may serve as a viable adjunct to conventional treatment. Addressing challenges to the widespread adoption of AI and VR in headache medicine, including reimbursement policies and data privacy concerns, mandates collaborative efforts from stakeholders to enable the equitable, safe, and effective utilization of these technologies in advancing headache disorder care. This review highlights the potential of AI and VR to support precise diagnostics, automate classification, and enhance management strategies for headache disorders.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38967712

RESUMEN

PURPOSE OF REVIEW: Diabetic neuropathy is a common complication of diabetes mellitus (DM) and can affect up to 50% of DM patients during their lifetime. Patients typically present with numbness, tingling, pain, and loss of sensation in the extremities. Since there is no treatment targeting the underlying mechanism of neuropathy, strategies focus on preventative care and pain management. RECENT FINDINGS: Up to 69% of patients with diabetic neuropathy receive pharmacological treatment for neuropathic pain. The United States Food and Drug Administration (FDA) confirmed four drugs for painful diabetic neuropathy (PDN): pregabalin, duloxetine, tapentadol, and the 8% capsaicin patch. Nonpharmacological treatments such as spinal cord stimulation (SCS) and transcutaneous electrical nerve stimulation (TENS) both show promise in reducing pain in DM patients. Despite the high burden associated with PDN, effective management remains challenging. This update covers the background and management of diabetic neuropathy, including its epidemiology, pathogenesis, preventative care, and current therapeutic strategies.

7.
J Pediatr Orthop ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38651447

RESUMEN

OBJECTIVE: Medial epicondyle fractures are a common pediatric injury. When operative, cannulated partially threaded screws, with or without a washer, are commonly utilized. These implants may need to be removed after full healing if symptomatic. There is mixed evidence regarding the influence of a washer on rates of implant removal, and the influence of screw size has not been studied. We aim to determine the rate of symptomatic deep implant removal for each fixation type and identify factors associated with the need for removal. METHODS: This was an IRB-reviewed, retrospective, case-cohort study. Patients treated at our institution between January 1, 2004 and December 31, 2019, age 18 years old or younger, with a medial epicondyle fracture managed operatively with 4.0 or 4.5 mm cannulated screws with or without washers were included. Patients with multiple operative ipsilateral elbow fractures and those who underwent implant removal for reasons other than pain or irritation were excluded. Removal rates were compared between screw sizes (4.0 vs 4.5 mm), as well as with and without a washer using a Cox proportional hazards model. RESULTS: In total, 151 patients met the inclusion criteria, 54 with symptomatic hardware removed and 97 without symptomatic hardware removed. A significantly higher number of patients treated with 4.5 mm screws compared with 4.0 mm screws underwent removal of symptomatic deep implants (50% vs 30%, P = 0.033). In a multivariable Cox regression model adjusting for age and ulnar nerve status, when no washer was used, the hazard ratio (HR) for symptomatic hardware removal for 4.5 mm screws was 2.92 times the HR for 4.0 mm screws (95% CI: 1.35-6.29). When a 4.0 mm screw was used, the HR for symptomatic hardware removal for a washer was 3.24 times the HR without a washer (95% CI: 1.53-6.84). CONCLUSION: Implant removal rates are influenced by screw size and the use of a washer. These results may help guide implant choice and counsel families regarding the rate of symptomatic implant removal. LEVEL OF EVIDENCE: Level III-therapeutic level, case-control study.

8.
Am J Physiol Lung Cell Mol Physiol ; 325(5): L542-L551, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37697925

RESUMEN

The use of respiratory support strategies such as continuous positive airway pressure in premature infants can substantially stretch highly compliant perinatal airways, leading to airway hyperreactivity and remodeling in the long term. The mechanisms by which stretch detrimentally affects the airway are unknown. Airway smooth muscle cells play a critical role in contractility and remodeling. Using 18-22-wk gestation human fetal airway smooth muscle (fASM) as an in vitro model, we tested the hypothesis that mechanosensitive Piezo (PZ) channels contribute to stretch effects. We found that PZ1 and PZ2 channels are expressed in the smooth muscle of developing airways and that their expression is influenced by stretch. PZ activation via agonist Yoda1 or stretch results in significant [Ca2+]i responses as well as increased extracellular matrix production. These data suggest that functional PZ channels may play a role in detrimental stretch-induced airway changes in the context of prematurity.NEW & NOTEWORTHY Piezo channels were first described just over a decade ago and their function in the lung is largely unknown. We found that piezo channels are present and functional in the developing airway and contribute to intracellular calcium responses and extracellular matrix remodeling in the setting of stretch. This may improve our understanding of the mechanisms behind development of chronic airway diseases, such as asthma, in former preterm infants exposed to respiratory support, such as continuous positive airway pressure (CPAP).


Asunto(s)
Asma , Recien Nacido Prematuro , Humanos , Recién Nacido , Músculo Liso/metabolismo , Pulmón/metabolismo , Asma/metabolismo , Miocitos del Músculo Liso/metabolismo
9.
Am J Physiol Lung Cell Mol Physiol ; 325(1): L17-L29, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37192375

RESUMEN

Although nicotinic acetylcholine receptors (nAChRs) are commonly associated with neurons in the brain and periphery, recent data indicate that they are also expressed in non-neuronal tissues. We recently found the alpha7 (α7nAChR) subunit is highly expressed in human airway smooth muscle (hASM) with substantial increase in asthmatics, but their functionality remains unknown. We investigated the location and functional role of α7nAChRs in hASM cells from normal versus mild-moderate asthmatic patients. Immunostaining and protein analyses showed α7nAChR in the plasma membrane including in asthmatics. In asthmatic hASM, patch-clamp recordings revealed significantly higher functional homomeric α7nAChR channels. Real-time fluorescence imaging showed nicotine, via α7nAChR, increases intracellular Ca2+ ([Ca2+]i) independent of ACh effects, particularly in asthmatic hASM, while cellular traction force microscopy showed nicotine-induced contractility including in asthmatics. These results indicate functional homomeric and heteromeric nAChRs that are increased in asthmatic hASM, with pharmacology that likely differ owing to different subunit interfaces that form the orthosteric sites. nAChRs may represent a novel target in alleviating airway hyperresponsiveness in asthma.NEW & NOTEWORTHY Cigarette smoking and vaping exacerbate asthma. Understanding the mechanisms of nicotine effects in asthmatic airways is important. This study demonstrates that functional alpha7 nicotinic acetylcholine receptors (α7nAChRs) are expressed in human airway smooth muscle, including from asthmatics, and enhance intracellular calcium and contractility. Although a7nAChRs are associated with neuronal pathways, α7nAChR in smooth muscle suggests inhaled nicotine (e.g., vaping) can directly influence airway contractility. Targeting α7nAChR may represent a novel approach to alleviating airway hyperresponsiveness in asthma.


Asunto(s)
Asma , Receptores Nicotínicos , Humanos , Receptor Nicotínico de Acetilcolina alfa 7 , Nicotina/farmacología , Calcio/metabolismo , Asma/metabolismo , Receptores Nicotínicos/metabolismo , Músculo Liso/metabolismo
10.
Childs Nerv Syst ; 39(8): 2155-2160, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36947197

RESUMEN

PURPOSE: Carbonated calcium phosphate (CCP) cement is an alloplastic material which has been increasingly utilized for cranioplasty reconstruction; however, there is a paucity of data investigating its use in patients with syndromic craniosynostosis. The purpose of this study was to characterize our institutional experience with CCP cement for secondary contouring cranioplasty in these patients to establish safety and aesthetic efficacy. METHODS: Patients with syndromic craniosynostosis undergoing cranioplasty with CCP cement from 2009 to 2022 were retrospectively reviewed for prior medical and surgical history, cranioplasty size, cement usage, and postoperative complications. Aesthetic ratings of the forehead region were quantified using the Whitaker scoring system at three timepoints: preoperative (T1), < 6 months postoperative (T2), and > 1 year postoperative (T3). RESULTS: Twenty-one patients were included. Age at surgery was 16.2 ± 2.8 years, forehead cranioplasty area was 135 ± 112 cm2, and mass of cement was 17.2 ± 7.8 g. Patients were followed for 3.0 ± 3.1 years. Whitaker scores decreased from 1.9 ± 0.4 at T1 to 1.4 ± 0.5 at T2 (p = 0.005). Whitaker scores at T2 and T3 were not significantly different (p = 0.720). Two infectious complications (9.5%) were noted, one at 4.5 months postoperatively and the other at 23 months, both requiring operative removal of CCP cement. CONCLUSION: Our results suggest that aesthetic forehead ratings improve after CCP contouring cranioplasty and that the improvement is sustained in medium-term follow-up. Complications were uncommon, suggesting that CCP is relatively safe though longer-term follow-up is needed before reaching definitive conclusions.


Asunto(s)
Craneosinostosis , Procedimientos de Cirugía Plástica , Humanos , Adolescente , Adulto Joven , Adulto , Estudios Retrospectivos , Cráneo/cirugía , Craneosinostosis/cirugía , Craneosinostosis/complicaciones , Cementos para Huesos/uso terapéutico , Complicaciones Posoperatorias/etiología , Fosfatos de Calcio/uso terapéutico
11.
Am J Drug Alcohol Abuse ; 49(4): 418-430, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-36880845

RESUMEN

Background: The neuroanatomy of craving, typically investigated using the functional magnetic resonance imaging (fMRI) drug cue reactivity (FDCR) paradigm, has been shown to involve the mesocorticolimbic, nigrostriatal, and corticocerebellar systems in several substances. However, the neuroanatomy of craving in heroin use disorder is still unclear.Objective: The current meta-analysis examines previous research on the neuroanatomy of craving in abstinent individuals with opioid use disorder (OUD).Method: Seven databases were searched for studies comparing abstinent OUD versus healthy controls on drug > neutral contrast interaction at the whole-brain level. Voxel-based meta-analysis was performed using seed-based d mapping with permuted subject images (SDM-PSI). Thresholds were set at a family-wise error rate of less than 5% with the default pre-processing parameters of SDM-PSI.Results: A total of 10 studies were included (296 OUD and 187 controls). Four hyperactivated clusters were identified with Hedges' g of peaks that ranged from 0.51 to 0.82. These peaks and their associated clusters correspond to the three systems identified in the previous literature: a) mesocorticolimbic, b) nigrostriatal, and c) corticocerebellar. There were also newly revealed hyperactivation regions including the bilateral cingulate, precuneus, fusiform gyrus, pons, lingual gyrus, and inferior occipital gyrus. The meta-analysis did not reveal areas of hypoactivation.Conclusion: Recommendations based on the functional neuroanatomical findings of this meta-analysis include pharmacological interventions such as buprenorphine/naloxone and cognitive-behavioral treatments such as cue-exposure combined with HRV biofeedback. In addition, research should utilize FDCR as pre- and post-measurement to determine the effectiveness and mechanism of action of such interventions.


Asunto(s)
Dependencia de Heroína , Trastornos Relacionados con Opioides , Humanos , Heroína , Ansia , Neuroanatomía , Imagen por Resonancia Magnética , Señales (Psicología) , Encéfalo
12.
J Pediatr Orthop ; 43(8): e639-e642, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37253708

RESUMEN

BACKGROUND: Achondroplasia is the most prevalent form of skeletal dysplasia, affecting more than 250,000 individuals. Lower extremity angular deformities, particularly genu varum, are common in children with achondroplasia, often resulting in pain and limitation of function. The authors aim to determine the utility of lower extremity growth modulation with hemiepiphysiodesis in children with achondroplasia for correction of coronal plane deformities about the knee. METHODS: The authors performed a retrospective chart review of a single center from 1/1/2000 to 12/31/2020 to identify pediatric patients with achondroplasia treated with hemiepiphysiodesis as their initial procedure at the distal femur and/or proximal tibia. Patients with adequate records and who had completed their treatment were included. Data collected included duration of treatment, complications, need for osteotomy, and radiographic measurements including initial and final mechanical axis deviation, knee mechanical axis zone, mechanical lateral distal femoral angle and medial proximal tibia angle. RESULTS: Ten patients with 17 limbs met our criteria. Nine patients (15 limbs) were treated for genu varum and 1 patient (2 limbs) was treated for genu valgum. Prior to treatment, the mechanical axis fell in zone 3 in 59% of limbs and zone 2 in 41%. Average correction in mechanical axis deviation was 26.1 mm. Average change in mechanical lateral distal femoral angle was 10.3 degrees per limb, and average change in medial proximal tibia angle was 7.1 degrees per limb. Average treatment duration was 909 days. At final follow up, 81% (14/17) of limbs had the mechanical axis in zone 1, with the remaining 18% (3/17) in zone 2. No patient/limb underwent subsequent distal femur or proximal tibia osteotomy for coronal plane alignment. CONCLUSIONS: Children with achondroplasia can successfully be treated with hemiepiphysiodesis to correct coronal plane deformities at the distal femur and proximal tibia. Using this technique, no patient in our series required an osteotomy for genu varum/valgum. LEVEL OF EVIDENCE: Therapeutic level IV, Case series.


Asunto(s)
Acondroplasia , Genu Valgum , Genu Varum , Humanos , Niño , Tibia/cirugía , Tibia/anomalías , Genu Varum/diagnóstico por imagen , Genu Varum/cirugía , Estudios Retrospectivos , Extremidad Inferior , Fémur/diagnóstico por imagen , Fémur/cirugía , Fémur/anomalías , Acondroplasia/complicaciones , Acondroplasia/cirugía , Genu Valgum/cirugía , Genu Valgum/complicaciones
13.
Telemed J E Health ; 29(11): 1713-1722, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-36912813

RESUMEN

Objective: The COVID-19 pandemic served as an impetus for the rapid expansion of telehealth. In this study, we examined the experience of rapid transition to telemental health (TMH) within The Family Health Centers at NYU Langone, a large, urban, Federally Qualified Health Center, in the 3 months after the onset of the COVID-19 pandemic. Methods: We administered surveys to clinicians and patients who utilized TMH between March 16, 2020 and July 16, 2020. Patients were sent a web-based survey via email or received a phone survey (for those without email) with four languages choices: English, Spanish, Traditional Chinese, or Simplified Chinese. Results: The majority (79%) of clinicians (n = 83) rated the experience of TMH as "excellent" or "good," and felt that they could establish and maintain the patient relationship through TMH. Four thousand seven hundred seventy-two survey invitations were sent out to patients, and 654 (13.7%) responded. Ninety percent reported that they were satisfied with the service they received and rated TMH as better or the same as in-person care (81.6%) with a high mean satisfaction score (4.5 out of 5). Patients were more likely to rate TMH as better or the same as in-person care relative to the clinicians. Conclusions: These results are consistent with several recent studies that have explored patient satisfaction with TMH during the COVID-19 pandemic and demonstrate that both clinicians and patients experienced a high degree of satisfaction with mental health care delivered virtually compared with face-to-face encounters.


Asunto(s)
COVID-19 , Servicios de Salud Mental , Telemedicina , Humanos , COVID-19/epidemiología , Pandemias , Satisfacción del Paciente , Telemedicina/métodos , Instituciones de Atención Ambulatoria , Satisfacción Personal
14.
J Hepatol ; 77(1): 128-139, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35139400

RESUMEN

BACKGROUND & AIMS: There is controversy regarding the overall value of hepatocellular carcinoma (HCC) surveillance in patients with cirrhosis given the lack of data from randomized-controlled trials. To address this issue, we conducted a systematic review and meta-analysis of cohort studies evaluating the benefits and harms of HCC surveillance in patients with cirrhosis. METHODS: We performed a search of the Medline and EMBASE databases and national meeting abstracts from January 2014 through July 2020 for studies reporting early-stage HCC detection, curative treatment receipt, or overall survival, stratified by HCC surveillance status, among patients with cirrhosis. Pooled risk ratios (RRs) and hazard ratios, according to HCC surveillance status, were calculated for each outcome using the DerSimonian and Laird method for random effects models. RESULTS: We identified 59 studies including 145,396 patients with HCC, which was detected by surveillance in 41,052 (28.2%) cases. HCC surveillance was associated with improved early-stage detection (RR 1.86, 95% CI 1.73-1.98; I2 = 82%), curative treatment receipt (RR 1.83, 95% CI 1.69-1.97; I2 = 75%), and overall survival (hazard ratio 0.67, 95% CI 0.61-0.72; I2 = 78%) after adjusting for lead-time bias; however, there was notable heterogeneity in all pooled estimates. Four studies examined surveillance-related physical harms due to false positive or indeterminate surveillance results, but no studies examined potential financial or psychological harms. The proportion of patients experiencing surveillance-related physical harms ranged from 8.8% to 27.5% across studies, although most harms were mild in severity. CONCLUSION: HCC surveillance is associated with improved early detection, curative treatment receipt, and survival in patients with cirrhosis, although there was heterogeneity in pooled estimates. Available data suggest HCC surveillance is of high value in patients with cirrhosis, although continued rigorous studies evaluating benefits and harms are still needed. LAY SUMMARY: There has been ongoing debate about the overall value of hepatocellular carcinoma (HCC) screening in patients with cirrhosis given the lack of data from randomized-controlled trials. In a systematic review of contemporary cohort studies, we found that HCC screening is associated with improved early detection, curative treatment receipt, and survival in patients with cirrhosis, although there were fewer data quantifying potential screening-related harms. Available data suggest HCC screening is of high value in patients with cirrhosis, although continued studies evaluating benefits and harms are still needed.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/terapia , Diagnóstico Precoz , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/epidemiología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/terapia , Tamizaje Masivo/métodos
15.
Phys Rev Lett ; 129(9): 097202, 2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36083647

RESUMEN

Recent experiments on Ce_{2}Zr_{2}O_{7} suggest that this material may host a novel form of quantum spin ice, a three-dimensional quantum spin liquid with an emergent photon. The Ce^{3+} local moments on the pyrochlore lattice are described by pseudospin-1/2 degrees of freedom, whose components transform as dipolar and octupolar moments under symmetry operations. In principle, there exist four possible quantum spin ice regimes, depending on whether the Ising component is in the dipolar or octupolar channel, and two possible flux configurations of the emergent gauge field. In this Letter, using exact diagonalization and molecular dynamics, we investigate the equal-time and dynamical spin structure factors in all four quantum spin ice regimes using quantum and classical calculations. Contrasting the distinct signatures of quantum and classical results for the four possible quantum spin ice regimes and elucidating the role of quantum fluctuations, we show that the quantum structure factor computed for the π-flux octupolar quantum spin ice regime is most compatible with the neutron scattering results on Ce_{2}Zr_{2}O_{7}.

16.
Mol Psychiatry ; 26(6): 1996-2012, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32541930

RESUMEN

Microvascular pathology and ischemic lesions contribute substantially to neuronal dysfunction and loss that lead to Alzheimer disease (AD). To facilitate recovery, the brain stimulates neovascularization of damaged tissue via sprouting angiogenesis, a process regulated by endothelial cell (EC) sprouting and the EphB4/ephrinB2 system. Here, we show that in cultures of brain ECs, EphB4 stimulates the VE-cadherin/Rok-α angiogenic complexes known to mediate sprouting angiogenesis. Importantly, brain EC cultures expressing PS1 FAD mutants decrease the EphB4-stimulated γ-secretase cleavage of ephrinB2 and reduce production of the angiogenic peptide ephrinB2/CTF2, the VE-cadherin angiogenic complexes and EC sprouting and tube formation. These data suggest that FAD mutants may attenuate ischemia-induced brain angiogenesis. Supporting this hypothesis, ischemia-induced VE-cadherin angiogenic complexes, levels of neoangiogenesis marker Endoglin, vascular density, and cerebral blood flow recovery, are all decreased in brains of mouse models expressing PS1 FAD mutants. Ischemia-induced brain neuronal death and cognitive deficits also increase in these mice. Furthermore, a small peptide comprising the C-terminal sequence of peptide ephrinB2/CTF2 rescues angiogenic functions of brain ECs expressing PS1 FAD mutants. Together, our data show that PS1 FAD mutations impede the EphB4/ephrinB2-mediated angiogenic functions of ECs and impair brain neovascularization, neuronal survival and cognitive recovery following ischemia. Furthermore, our data reveal a novel brain angiogenic mechanism targeted by PS1 FAD mutants and a potential therapeutic target for ischemia-induced neurodegeneration. Importantly, FAD mutant effects occur in absence of neuropathological hallmarks of AD, supporting that such hallmarks may form downstream of mutant effects on neoangiogenesis and neuronal survival.


Asunto(s)
Efrina-B2 , Flavina-Adenina Dinucleótido , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Animales , Encéfalo/metabolismo , Proteínas Portadoras , Efrina-B2/genética , Efrina-B2/metabolismo , Ratones , Presenilina-1/genética
17.
Phys Chem Chem Phys ; 24(42): 26102-26110, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36274571

RESUMEN

Nucleation and crystallization arising from liquid to solid phase are involved in a multitude of processes in fields ranging from materials science to biology. Controlling the thermodynamics and kinetics of growth is advantageous to help tune the formation of complex morphologies. Here, we harness wide-angle X-ray scattering and vibrational spectroscopy to elucidate the mechanism for crystallization and growth of the metal-organic framework Co-MOF-74 within microscopic volumes enclosed in a capillary and an attenuated total reflection microchip reactor. The experiments reveal molecular and structural details of the growth processes, while the results of plane wave density functional calculations allow identification of lattice and linker modes in the formed crystals. Synthesis of the metal-organic framework with microscopic volumes leads to monodisperse and micron-sized crystals, in contrast to those typically observed under bulk reaction conditions. Reduction in the volume of reagents within the microchip reactor was found to accelerate the reaction rate. The coupling of spectroscopy with scattering to probe reactions in microscopic volumes promises to be a useful tool in the synthetic chemist's kit to understand chemical bonding and has potential in designing complex materials.


Asunto(s)
Estructuras Metalorgánicas , Estructuras Metalorgánicas/química , Rayos X , Cristalización , Termodinámica , Espectroscopía de Resonancia Magnética
18.
Proc Natl Acad Sci U S A ; 116(22): 10917-10926, 2019 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-31088972

RESUMEN

T cell cytokines contribute to immunity against Staphylococcus aureus, but the predominant T cell subsets involved are unclear. In an S. aureus skin infection mouse model, we found that the IL-17 response was mediated by γδ T cells, which trafficked from lymph nodes to the infected skin to induce neutrophil recruitment, proinflammatory cytokines IL-1α, IL-1ß, and TNF, and host defense peptides. RNA-seq for TRG and TRD sequences in lymph nodes and skin revealed a single clonotypic expansion of the encoded complementarity-determining region 3 amino acid sequence, which could be generated by canonical nucleotide sequences of TRGV5 or TRGV6 and TRDV4 However, only TRGV6 and TRDV4 but not TRGV5 sequences expanded. Finally, Vγ6+ T cells were a predominant γδ T cell subset that produced IL-17A as well as IL-22, TNF, and IFNγ, indicating a broad and substantial role for clonal Vγ6+Vδ4+ T cells in immunity against S. aureus skin infections.


Asunto(s)
Interleucina-17/fisiología , Infecciones Estafilocócicas/inmunología , Staphylococcus aureus/patogenicidad , Subgrupos de Linfocitos T/inmunología , Linfocitos T/inmunología , Animales , Modelos Animales de Enfermedad , Humanos , Ganglios Linfáticos/inmunología , Ratones , Infecciones Estafilocócicas/microbiología
19.
Curr Psychol ; : 1-18, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36345548

RESUMEN

The outbreak of COVID-19 has led to a global health crisis and caused huge emotional swings. However, the positive emotional expressions, like self-confidence, optimism, and praise, that appear in Chinese social networks are rarely explored by researchers. This study aims to analyze the characteristics of netizens' positive energy expressions and the impact of node events on public emotional expression during the COVID-19 pandemic. First, a total of 6,525,249 Chinese texts posted by Sina Weibo users were randomly selected through textual data cleaning and word segmentation for corpus construction. A fine-grained sentiment lexicon that contained POSITIVE ENERGY was built using Word2Vec technology; this lexicon was later used to conduct sentiment category analysis on original posts. Next, through manual labeling and multi-classification machine learning model construction, four mainstream machine learning algorithms were selected to train the emotional intensity model. Finally, the lexicon and optimized emotional intensity model were used to analyze the emotional expressions of Chinese netizens. The results show that POSITIVE ENERGY expression accounted for 40.97% during the COVID-19 pandemic. Over the course of time, POSITIVE ENERGY emotions were displayed at the highest levels and SURPRISES the lowest. The analysis results of the node events showed after the outbreak was confirmed officially, the expressions of POSITIVE ENERGY and FEAR increased simultaneously. After the initial victory in pandemic prevention and control, the expression of POSITIVE ENERGY and SAD reached a peak, while the increase of SAD was the most prominent. The fine-grained sentiment lexicon, which includes a POSITIVE ENERGY category, demonstrated reliable algorithm performance and can be used for sentiment classification of Chinese Internet context. We also found many POSITIVE ENERGY expressions in Chinese online social platforms which are proven to be significantly affected by nod events of different nature.

20.
Clin Gastroenterol Hepatol ; 19(10): 2202-2204, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33007508

RESUMEN

Nonalcoholic fatty liver disease (NAFLD), the most common cause of chronic liver disease,1 is independently associated with increased risk of cardiovascular disease (CVD), which is the leading cause of mortality in patients with NAFLD.2 This is likely caused by the centrality of the liver in lipid homeostasis. Prior cross-sectional studies have shown that NAFLD is associated with perturbations in lipid profile and atherogenic lipoprotein subparticles.3 Although statins improve lipid profile and CVD-associated mortality, residual CVD risk has been demonstrated in major statin trials.4,5 A key contributor to this residual risk is the limited ability of the standard lipid profile to precisely quantify atherogenic lipoprotein subparticles, such as small dense low-density lipoprotein (sdLDL), which might confer higher atherogenic risk. There are currently no studies evaluating the longitudinal impact of sdLDL on atherosclerotic events in NAFLD. Thus, we conducted a prospective study in patients with histologically confirmed NAFLD to better define the relationship among NAFLD, residual CVD risk, and sdLDL.


Asunto(s)
Aterosclerosis , Enfermedades Cardiovasculares , Enfermedad del Hígado Graso no Alcohólico , Aterosclerosis/epidemiología , Estudios Transversales , Humanos , Lipoproteínas , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Estudios Prospectivos , Factores de Riesgo
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