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1.
Circulation ; 150(14): 1075-1086, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39166326

RESUMO

BACKGROUND: Coronary microvascular dysfunction has been implicated in the development of hypertensive heart disease and heart failure, with subendocardial ischemia identified as a driver of sustained myocardial injury and fibrosis. We aimed to evaluate the relationships of subendocardial perfusion with cardiac injury, structure, and a composite of major adverse cardiac and cerebrovascular events consisting of death, heart failure hospitalization, myocardial infarction, and stroke. METHODS: Layer-specific blood flow and myocardial flow reserve (MFR; stress/rest myocardial blood flow) were assessed by 13N-ammonia perfusion positron emission tomography in consecutive patients with hypertension without flow-limiting coronary artery disease (summed stress score <3) imaged at Brigham and Women's Hospital (Boston, MA) from 2015 to 2021. In this post hoc observational study, biomarkers, echocardiographic parameters, and longitudinal clinical outcomes were compared by tertiles of subendocardial MFR (MFRsubendo). RESULTS: Among 358 patients, the mean age was 70.6±12.0 years, and 53.4% were male. The median MFRsubendo was 2.57 (interquartile range, 2.08-3.10), and lower MFRsubendo was associated with older age, diabetes, lower renal function, greater coronary calcium burden, and higher systolic blood pressure (P<0.05 for all). In cross-sectional multivariable regression analyses, the lowest tertile of MFRsubendo was associated with myocardial injury and with greater left ventricular wall thickness and volumes compared with the highest tertile. Relative to the highest tertile, low MFRsubendo was independently associated with an increased rate of major adverse cardiac and cerebrovascular events (adjusted hazard ratio, 2.99 [95% CI, 1.39-6.44]; P=0.005) and heart failure hospitalization (adjusted hazard ratio, 2.76 [95% CI, 1.04-7.32; P=0.042) over 1.1 (interquartile range, 0.6-2.8) years median follow-up. CONCLUSIONS: Among patients with hypertension without flow-limiting coronary artery disease, impaired MFRsubendo was associated with cardiovascular risk factors, elevated cardiac biomarkers, cardiac structure, and clinical events.


Assuntos
Hipertensão , Humanos , Masculino , Feminino , Idoso , Hipertensão/fisiopatologia , Hipertensão/complicações , Pessoa de Meia-Idade , Circulação Coronária , Idoso de 80 Anos ou mais , Miocárdio/patologia , Tomografia por Emissão de Pósitrons
2.
Cell Mol Life Sci ; 81(1): 88, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349408

RESUMO

Atrial fibrillation (AF) is the most prevalent sustained cardiac arrhythmia, and recent epidemiological studies suggested type 2 diabetes mellitus (T2DM) is an independent risk factor for the development of AF. Zinc finger and BTB (broad-complex, tram-track and bric-a-brac) domain containing 16 (Zbtb16) serve as transcriptional factors to regulate many biological processes. However, the potential effects of Zbtb16 in AF under T2DM condition remain unclear. Here, we reported that db/db mice displayed higher AF vulnerability and Zbtb16 was identified as the most significantly enriched gene by RNA sequencing (RNA-seq) analysis in atrium. In addition, thioredoxin interacting protein (Txnip) was distinguished as the key downstream gene of Zbtb16 by Cleavage Under Targets and Tagmentation (CUT&Tag) assay. Mechanistically, increased Txnip combined with thioredoxin 2 (Trx2) in mitochondrion induced excess reactive oxygen species (ROS) release, calcium/calmodulin-dependent protein kinase II (CaMKII) overactivation, and spontaneous Ca2+ waves (SCWs) occurrence, which could be inhibited through atrial-specific knockdown (KD) of Zbtb16 or Txnip by adeno-associated virus 9 (AAV9) or Mito-TEMPO treatment. High glucose (HG)-treated HL-1 cells were used to mimic the setting of diabetic in vitro. Zbtb16-Txnip-Trx2 signaling-induced excess ROS release and CaMKII activation were also verified in HL-1 cells under HG condition. Furthermore, atrial-specific Zbtb16 or Txnip-KD reduced incidence and duration of AF in db/db mice. Altogether, we demonstrated that interrupting Zbtb16-Txnip-Trx2 signaling in atrium could decrease AF susceptibility via reducing ROS release and CaMKII activation in the setting of T2DM.


Assuntos
Fibrilação Atrial , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Animais , Camundongos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteínas de Transporte/genética , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Proteína com Dedos de Zinco da Leucemia Promielocítica , Espécies Reativas de Oxigênio , Tiorredoxinas/genética
3.
BMC Plant Biol ; 24(1): 6, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38163891

RESUMO

Unpredictable rainfall frequently results in excess moisture, which is detrimental to the landscape because it interferes with the genetic, morphological, and physiological processes of plants, even though the majority of urban landscapes frequently experience moisture shortages. A study was conducted to analyze the effects of a 36-day waterlogging phase and a subsequent 12-day recovery period on the morpho-physiological responses of 17 Crassulaceae species with the goal of identifying those which were more tolerant of the conditions. Results revealed that waterlogging stress has an impact on all morpho-physiological parameters. Sensitive materials (S7, Hylotelephium telephium 'Purple Emperor' and S15, S. sexangulare) showed severe ornamental quality damage, mortality, decreases in total dry biomass, root-shoot ratio, and chlorophyll content, as well as higher MDA concentrations. Lower reductions in these parameters, along with improved antioxidant enzyme activities and greater recovery capabilities after drainage, were observed in the most tolerant materials S2 (H. spectabile 'Brilliant'), S3 (H. spectabile 'Carl'), and S5 (H. telephium 'Autumn Joy'). Furthermore, with the exception of early death materials (S7 and S15), all materials showed varying intensities of adventitious root formation in response to waterlogging. The 17 species were divided into 4 clusters based on the comprehensive evaluation value. The first group included S1-S3, S5-S6, S8-S12, which were waterlogged tolerant with the highest values (0.63-0.82). S14 belongs to the intermediate waterlogging tolerant. S4, S13, S16, and S17 were clustered into the low waterlogging-tolerant group. S7 and S15 were the most susceptible to waterlogging. The survival and success of Crassulaceae species (especially, the first and second cluster), throughout this prolonged period of waterlogging (36 days) and recovery were attributed to a combination of physiological and morphological responses, indicating that they are an appealing species for the creation of rain gardens or obstructed drainage locations.


Assuntos
Clorofila , Estações do Ano , Biomassa
4.
J Chem Phys ; 160(4)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38265089

RESUMO

We utilized molecular dynamic simulation to investigate the glass formation of star polymer melts in which the topological complexity is varied by altering the number of star arms (f). Emphasis was placed on how the "confinement effect" of repulsive inter-arm interactions within star polymers influences the thermodynamics and dynamics of star polymer melts. All the characteristic temperatures of glass formation were found to progressively increase with increasing f, but unexpectedly the fragility parameter KVFT was found to decrease with increasing f. As previously observed, stars having more than 5 or 6 arms adopt an average particle-like structure that is more contracted relative to the linear polymer size having the same mass and exhibit a strong tendency for intermolecular and intramolecular segregation. We systematically analyzed how varying f alters collective particle motion, dynamic heterogeneity, the decoupling exponent ζ phenomenologically linking the slow ß- and α-relaxation times, and the thermodynamic scaling index γt. Consistent with our hypothesis that the segmental dynamics of many-arm star melts and thin supported polymer films should exhibit similar trends arising from the common feature of high local segmental confinement, we found that ζ increases considerably with increasing f, as found in supported polymer films with decreasing thickness. Furthermore, increasing f led to greatly enhanced elastic heterogeneity, and this phenomenon correlates strongly with changes in ζ and γt. Our observations should be helpful in building a more rational theoretical framework for understanding how molecular topology and geometrical confinement influence the dynamics of glass-forming materials more broadly.

5.
J Chem Phys ; 160(6)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38341796

RESUMO

We study the dynamics of the end monomers of a real chain confined in a spherical cavity to search for a small target on the cavity surface using Langevin dynamics simulation. The results are compared and contrasted with those of a Rouse chain to understand the influence of excluded volume interactions on the search dynamics, as characterized by the first passage time (FPT). We analyze how the mean FPT depends on the cavity size Rb, the target size a, and the degree of confinement quantified by Rg/Rb, with Rg being the polymer radius of gyration in free space. As a basic finding, the equilibrium distribution of the end monomers of a real chain in a closed spherical cavity differs from that of a Rouse chain at a given Rg/Rb, which leads to the differences between the mean FPTs of real and Rouse chains. Fitting the survival probability S(t) by a multi-exponential form, we show that the S(t) of real chains exhibits multiple characteristic times at large Rg/Rb. Our simulation results indicate that the search dynamics of a real chain exhibit three characteristic regimes as a function of Rg/Rb, including the transition from the Markovian to non-Markovian process at Rg/Rb ≈ 0.39, along with two distinct regimes at 0.39 < Rg/Rb < 1.0 and Rg/Rb > 1.0, respectively, where S(t) exhibits a single characteristic time and multiple characteristic times.

6.
J Appl Clin Med Phys ; 25(5): e14343, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569013

RESUMO

PURPOSE: Single-isocenter multi-target intracranial stereotactic radiotherapy (SIMT) is an effective treatment for brain metastases with complex treatment plans and delivery optimization necessitating rigorous quality assurance. This work aims to assess five methods for quality assurance of SIMT treatment plans in terms of their suitability and sensitivity to delivery errors. METHODS: Sun Nuclear ArcCHECK and SRS MapCHECK, GafChromic EBT Radiochromic Film, machine log files, and Varian Portal Dosimetry were all used to measure 15 variations of a single SIMT plan. Variations of the original plan were created with Python. They comprised various degrees of systematic MLC offsets per leaf up to 2 mm, random per-leaf variations with differing minimum and maximum magnitudes, simulated collimator, and dose miscalibrations (MU scaling). The erroneous plans were re-imported into Eclipse and plan-quality degradation was assessed by comparing each plan variation to the original clinical plan in terms of the percentage of clinical goals passing relative to the original plan. Each erroneous plan could be then ranked by the plan-quality degradation percentage following recalculation in the TPS so that the effects of each variation could be correlated with γ pass rates and detector suitability. RESULTS & CONCLUSIONS: It was found that 2%/1 mm is a good starting point for the ArcCHECK, Portal Dosimetry, and the SRS MapCHECK methods, respectively, and provides clinically relevant error detection sensitivity. Looser dose criteria of 5%/1 mm or 5%/1.5 mm are suitable for film dosimetry and log-file-based methods. The statistical methods explored can be expanded to other areas of patient-specific QA and detector assessment.


Assuntos
Neoplasias Encefálicas , Garantia da Qualidade dos Cuidados de Saúde , Radiocirurgia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias Encefálicas/radioterapia , Radiocirurgia/métodos , Radiocirurgia/instrumentação , Garantia da Qualidade dos Cuidados de Saúde/normas , Radioterapia de Intensidade Modulada/métodos , Aceleradores de Partículas/instrumentação , Radiometria/métodos , Radiometria/instrumentação , Algoritmos
7.
Mamm Genome ; 34(2): 312-322, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36749382

RESUMO

Dilated cardiomyopathy (DCM) is a group of heart muscle diseases that often lead to heart failure, with more than 50 causative genes have being linked to DCM. The heterogenous nature of the inherited DCMs suggest the need of precision medicine. Consistent with this emerging concept, transcriptome studies in human patients with DCM indicated distinct molecular signature for DCMs of different genetic etiology. To facilitate this line of research, we reviewed the status of transcriptome studies of inherited DCMs by focusing on three predominant DCM causative genes, TTN, LMNA, and BAG3. Besides studies in human patients, we summarized transcriptomic analysis of these inherited DCMs in a variety of model systems ranging from iPSCs to rodents and zebrafish. We concluded that the RNA-seq technology is a powerful genomic tool that has already led to the discovery of new modifying genes, signaling pathways, and related therapeutic avenues. We also pointed out that both temporal (different pathological stages) and spatial (different cell types) information need to be considered for future transcriptome studies. While an important bottle neck is the low throughput in experimentally testing differentially expressed genes, new technologies in efficient animal models such as zebrafish starts to be developed. It is anticipated that the RNA-seq technology will continue to uncover both unique and common pathological events, aiding the development of precision medicine for inherited DCMs.


Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , Animais , Humanos , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/patologia , Transcriptoma/genética , Peixe-Zebra/genética , Perfilação da Expressão Gênica , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
9.
J Chem Phys ; 158(20)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37232438

RESUMO

We develop a theory for the motion of a particle grafted with inhomogeneous bead-spring Rouse chains via the generalized Langevin equation (GLE), where individual grafted polymers are allowed to take different bead friction coefficients, spring constants, and chain lengths. An exact solution of the memory kernel K(t) is obtained for the particle in the time (t) domain in the GLE, which depends only on the relaxation of the grafted chains. The t-dependent mean square displacement g(t) of the polymer-grafted particle is then derived as a function of the friction coefficient γ0 of the bare particle and K(t). Our theory offers a direct way to quantify the contributions of the grafted chain relaxation to the mobility of the particle in terms of K(t). This powerful feature enables us to clarify the effect on g(t) of dynamical coupling between the particle and grafted chains, leading to the identification of a relaxation time of fundamental importance in polymer-grafted particles, namely, the particle relaxation time. This timescale quantifies the competition between the contributions of the solvent and grafted chains to the friction of the grafted particle and separates g(t) into the particle- and chain-dominated regimes. The monomer relaxation time and the grafted chain relaxation time further divide the chain-dominated regime of g(t) into subdiffusive and diffusive regimes. Analysis of the asymptotic behaviors of K(t) and g(t) provides a clear physical picture of the mobility of the particle in different dynamical regimes, shedding light on the complex dynamics of polymer-grafted particles.

10.
Addict Biol ; 28(11): e13343, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37855071

RESUMO

Opioid use disorder (OUD) is a critical problem in China and is accompanied by depression and deficits in cognitive control. In China, the most successful intervention for OUD is the community drug rehabilitation where methadone maintenance treatment (MMT) plays a key role. Even though methadone for the treatment of OUD can be helpful, it can cause severe somatic side-effects, which limit its effectivity. Even worse, it can have detrimental effects on cognitive control, which is crucial to regain control over drug intake. Here, we consider the potential use of auricular transcutaneous vagus nerve stimulation (atVNS) as an addition to MMT for opioid withdrawal treatment. Compared to other non-invasive brain stimulation methods, atVNS also targets the locus coeruleus (LC) important for noradrenaline (NA) synthesis. NA is an essential neurotransmitter impacted in opioid withdrawal and also critically involved in cognitive control processes. Its ADD-ON to MMT might be a useful mean to improve mood and enhance cognitive control processes impacted in OUD. We discuss the translational advantages of atVNS in China such as the cultural acceptance of the modality of treatment similar to electroacupuncture. Additionally, the wearability of the ear electrode and at-home self-administration without intense medical supervision makes of atVNS a useful tool to enhance clinical and cognitive outcomes especially in everyday life situation. We discuss how atVNS can be integrated in tele-medical health approaches allowing that innovative treatments can widely be disseminated and continued even in situations of restricted medical access.


Assuntos
Transtornos Relacionados ao Uso de Opioides , Estimulação do Nervo Vago , Humanos , Analgésicos Opioides/uso terapêutico , Estimulação do Nervo Vago/métodos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , China , Metadona/uso terapêutico
11.
BMC Anesthesiol ; 23(1): 385, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-38001477

RESUMO

BACKGROUND: This study aims to estimate the safety, efficacy, and median effective dose (ED50) of esketamine for preventing early postoperative pain in patients undergoing laparoscopic cholecystectomy. METHODS: 54 patients undergoing laparoscopic cholecystectomy were prospectively randomized into two groups (group C and group E). Different doses of esketamine were intravenously administered before the skin incision in Group E. The patients in group C received the same dose of saline at the same time. General population characteristics were recorded. The median effective dose (ED50) and 95% effective dose (ED95) were calculated using Dixon's up-and-down method. Hemodynamic parameters were monitored, and pain intensity was assessed using a visual analog scale. We also recorded the condition of anesthesia recovery period and postoperative adverse reactions. RESULTS: The ED50 of esketamine for preventing early postoperative pain was 0.301 mg/kg (95%CI: 0.265-0.342 mg/kg), and the ED95 was 0.379 mg/kg (95%CI: 0.340-0.618 mg/kg), calculated by probability unit regression. Heart rate (HR) was significantly lower in the esketamine group compared to the control at the skin incision (p < 0.05). The total VAS score at resting was significantly lower in the esketamine group compared to the control group during the awakening period (p < 0.05). There was no significant difference between the two groups regarding the incidence of adverse reactions (p > 0.05). CONCLUSIONS: In this study, esketamine can prevent early postoperative pain effectively. The ED50 and ED95 of esketamine for controlling early postoperative pain were 0.301 mg/kg and 0.379 mg/kg, respectively. TRIAL REGISTRATION: ChiCTR2200066663, 13/12/2022.


Assuntos
Colecistectomia Laparoscópica , Humanos , Colecistectomia Laparoscópica/efeitos adversos , Colecistectomia Laparoscópica/métodos , Estudos Prospectivos , Dor Pós-Operatória/prevenção & controle , Dor Pós-Operatória/etiologia , Método Duplo-Cego
12.
Environ Toxicol ; 38(4): 914-925, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36602389

RESUMO

The dibutyl phthalate (DBP) has been detected in fetuses and infants and can cause damage to the reproductive system in adulthood, but the exact mechanism remains unclear. Here, we aim to investigate the effects of intrauterine DBP exposure on offspring reproductive function and explore possible mechanisms. SPF C57BL/6 pregnant mice were given DBP (0.5, 5, 75 mg/kg/d) or corn oil from day 5 to day 19 by gavage. After weaning, the pups were fed a standard diet for 5 weeks. In addition, TM3 Leydig cell cultures were used to study the relevant mechanisms in vitro. The results showed that intrauterine DBP exposure could reduce sperm density and sperm motility, cause testicular tissue damage, down-regulate serum T and LH levels, and up-regulate serum FSH levels at 75 mg/kg/d. Western blot and methylation detection revealed intrauterine exposure to DBP down-regulated testosterone synthesis-related proteins StAR, P450scc, 3ß-HSD, PKA, and PKC expression, while up-regulated the levels of methyltransferase proteins expression and DNA 5-methylcytosine (5mC) in testicular tissue of mouse offspring at 75 mg/kg/d. Further detection found in utero 75 mg/kg/d DBP exposure down-regulated MGARP protein expression, and induced incomplete methylation of the MGARP gene. An in vitro analysis showed that MGARP inhibition is involved in an impaired testosterone synthesis in TM3 cells. Cell culture results suggest that MGARP down-regulation may be involved in impaired testosterone production in monobutyl phthalate-treated cells. The present study revealed that 75 mg/kg/d DBP exposure in utero resulted in testosterone synthesis disorders and reproductive function impairment in mouse offspring, and the mechanism may be related to DNA methylation-mediated down-regulation of MGARP in the testis.


Assuntos
Metilação de DNA , Dibutilftalato , Animais , Feminino , Masculino , Camundongos , Gravidez , Dibutilftalato/farmacologia , Camundongos Endogâmicos C57BL , Sêmen/metabolismo , Motilidade dos Espermatozoides , Testículo , Testosterona
13.
Int J Mol Sci ; 24(4)2023 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-36835518

RESUMO

Arrhythmogenic cardiomyopathy (ACM) is largely an autosomal dominant genetic disorder manifesting fibrofatty infiltration and ventricular arrhythmia with predominantly right ventricular involvement. ACM is one of the major conditions associated with an increased risk of sudden cardiac death, most notably in young individuals and athletes. ACM has strong genetic determinants, and genetic variants in more than 25 genes have been identified to be associated with ACM, accounting for approximately 60% of ACM cases. Genetic studies of ACM in vertebrate animal models such as zebrafish (Danio rerio), which are highly amenable to large-scale genetic and drug screenings, offer unique opportunities to identify and functionally assess new genetic variants associated with ACM and to dissect the underlying molecular and cellular mechanisms at the whole-organism level. Here, we summarize key genes implicated in ACM. We discuss the use of zebrafish models, categorized according to gene manipulation approaches, such as gene knockdown, gene knock-out, transgenic overexpression, and CRISPR/Cas9-mediated knock-in, to study the genetic underpinning and mechanism of ACM. Information gained from genetic and pharmacogenomic studies in such animal models can not only increase our understanding of the pathophysiology of disease progression, but also guide disease diagnosis, prognosis, and the development of innovative therapeutic strategies.


Assuntos
Displasia Arritmogênica Ventricular Direita , Peixe-Zebra , Animais , Displasia Arritmogênica Ventricular Direita/genética , Modelos Animais , Arritmias Cardíacas , Morte Súbita Cardíaca
14.
Hepatology ; 74(3): 1251-1270, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33713358

RESUMO

BACKGROUND AND AIMS: Characterized by hepatocyte steatosis, inflammation, and fibrosis, NASH is a complicated process that contributes to end-stage liver disease and, eventually, HCC. TNF-α-induced protein 8-like 1 (TIPE1), a new member of the TNF-α-induced protein 8 family, has been explored in immunology and oncology research; but little is known about its role in metabolic diseases. APPROACH AND RESULTS: Here, we show that hepatocyte-specific deletion of TIPE1 exacerbated diet-induced hepatic steatosis, inflammation, and fibrosis as well as systemic metabolic disorders during NASH pathogenesis. Conversely, hepatocyte-specific overexpression of TIPE1 dramatically prevented the progression of these abnormalities. Mechanically, TIPE1 directly interacted with apoptosis signal-regulating kinase 1 (ASK1) to suppress its TNF receptor-associated factor 6 (TRAF6)-catalyzed polyubiquitination activation upon metabolic challenge, thereby inhibiting the downstream c-Jun N-terminal kinase and p38 signaling pathway. Importantly, dramatically reduced TIPE1 expression was observed in the livers of patients with NAFLD, suggesting that TIPE1 might be a promising therapeutic target for NAFLD and related metabolic diseases. CONCLUSIONS: TIPE1 protects against hepatic steatosis, inflammation, and fibrosis through directly binding ASK1 and restraining its TRAF6-catalyzed polyubiquitination during the development of NASH. Therefore, targeting TIPE1 could be a promising therapeutic approach for NAFLD treatment.


Assuntos
Fígado Gorduroso/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , MAP Quinase Quinase Quinase 5/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Adulto , Idoso , Animais , Dieta Hiperlipídica , Regulação para Baixo , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Feminino , Humanos , Inflamação , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Camundongos Knockout , Camundongos Transgênicos , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/metabolismo , Poliubiquitina/metabolismo
15.
Int J Neuropsychopharmacol ; 25(11): 912-923, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36053298

RESUMO

BACKGROUND: The neuropeptide oxytocin (OXT) modulates social cognition by increasing attention to social cues and may have therapeutic potential for impaired social attention in conditions such as autism spectrum disorder. Intranasal administration of OXT is widely used to examine the drug's functional effects in both adults and children and is assumed to enter the brain directly via this route. However, OXT can also influence brain function through increased blood concentrations, and we have recently shown that orally (lingual) administered OXT also modulates neural responses to emotional faces and may be better tolerated for therapeutic use. Here, we examine whether 24 IU OXT administered orally can facilitate social attention. METHODS: In a randomized, placebo-controlled pharmacologic study, we used a validated emotional antisaccade eye-tracking paradigm to explore the effects of oral OXT on bottom-up and top-down attention processing in 80 healthy male participants. RESULTS: Our findings showed that in terms of top-down attention, oral OXT increased errors for both social (angry, fearful, happy, sad, and neutral emotion faces) and nonsocial stimuli (oval shapes) in the antisaccade condition but increased response latencies only in the social condition. It also significantly reduced post-task state anxiety, but this reduction was not correlated with task performance. A comparison with our previous intranasal OXT study using the same task revealed that both routes have a similar effect on increasing antisaccade errors and response latencies and on reducing state anxiety. CONCLUSIONS: Overall, our findings suggest that oral administration of OXT produces similar effects on top-down social attention control and anxiety to intranasal administration and may therefore have therapeutic utility.


Assuntos
Transtorno do Espectro Autista , Ocitocina , Adulto , Criança , Masculino , Humanos , Ocitocina/farmacologia , Administração Intranasal , Expressão Facial , Método Duplo-Cego , Atenção , Administração Oral
16.
BMC Infect Dis ; 22(1): 677, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35941618

RESUMO

BACKGROUND: The most appropriate alternative to induction therapy for HIV-associated cryptococcal meningitis (CM) remains unclear when standard treatment is unavailable, inaccessible, intolerable, or ineffective. METHODS: A prospective, multi-centre cohort study was conducted to analyze the data of 156 HIV-infected patients with CM who were treated with amphotericin B deoxycholate (AmB-D) + flucytosine (5FC), voriconazole (VCZ) + 5FC, or AmB-D + Fluconazole (Flu) as induction regimens. Clinical efficacy, cumulative mortality, and adverse effects were compared among the three treatment groups. RESULTS: Fewer deaths occurred by week 4 and week 10 among patients receiving AmB-D + 5FC than among those receiving AmB-D + Flu [4 (5.1%) vs. 8 (16.0%) deaths by week 4; hazard ratio, 1.8; 95% confidence interval [CI], 1.0 to 3.3; p = 0.039; and 8 (10.3%) vs. 14 (28.0%) deaths by week 10; hazard ratio, 1.8; 95% CI, 1.1 to 2.7; p = 0.008, respectively]. AmB-D plus 5FC was found to result in significantly higher rates of cerebrospinal fluid (CSF) culture sterility (57.6% vs. 34% by week 2; 87.9% vs. 70% by week 10; p < 0.05 for both comparisons). However, the differences in CSF culture sterility and mortality between the VCZ + 5FC group and the AmB-D + 5FC group were not statistically significant. VCZ plus 5FC had a significantly advantageous effect on the incidence of new AIDS-defining illness and length of hospital stay, compared with AmB-D plus 5FC. Laboratory adverse events (grade 3 or 4), such as severe anemia, were less frequent with VCZ + 5FC use than with AmB-D combined with 5FC or Flu use. CONCLUSION: Our results suggest that AmB-D combined with 5FC remains the more efficacious induction regimen compared to AmB-D plus Flu, and that VCZ + 5FC might be a potential alternative when the standard regimen is not readily available, accessible, tolerated, or effective. CLINICAL TRIALS: Registration number, ChiCTR1900021195. Registered 1 February 2019, http://www.chictr.org.cn/showproj.aspx?proj=35362 .


Assuntos
Infecções por HIV , Infertilidade , Meningite Criptocócica , Anfotericina B , Antifúngicos/efeitos adversos , Estudos de Coortes , Ácido Desoxicólico , Combinação de Medicamentos , Quimioterapia Combinada , Fluconazol/efeitos adversos , Flucitosina/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Infertilidade/induzido quimicamente , Infertilidade/tratamento farmacológico , Estudos Prospectivos , Voriconazol/uso terapêutico
17.
J Chem Phys ; 157(22): 224901, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36546812

RESUMO

The generalized Langevin equation (GLE) provides an attractive theoretical framework for investigating the dynamics of conformational fluctuations of polymeric systems. While the memory kernel is a central function in the GLE, explicit analytical forms for this function have been challenging to obtain, even for the simple models of polymer dynamics. Here, we achieve an explicit analytical expression for the memory kernel in the GLE for the end-to-end vector of Rouse chains in the overdamped limit. Our derivation takes advantage of the finding that the dynamics of the end-to-end vector of Rouse chains with both free ends are equivalent to those of Rouse chains with one free end and the other fixed. For the latter model, we first show that the equations of motion of the Rouse modes as well as their statistical properties can be obtained under the boundary conditions where the free end is held fixed temporarily. We then analytically solve the terms associated with intrachain interactions in the GLE. By formally comparing these terms with the GLE based on the Rouse modes, we obtain an explicit expression for the memory kernel, along with analytical forms for the potential field and the random colored noise force. Our analytical memory kernel is confirmed by numerical calculations in the Laplace space and is shown to yield asymptotic behaviors that are consistent with previous studies. Finally, we utilize our analytical result to simulate the cyclization dynamics of Rouse chains and discuss the scaling of the cyclization time with chain length.


Assuntos
Polímeros , Conformação Molecular , Movimento (Física)
18.
J Am Soc Nephrol ; 32(4): 822-836, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33574160

RESUMO

BACKGROUND: Although zebrafish embryos have been used to study ciliogenesis and model polycystic kidney disease (PKD), adult zebrafish remain unexplored. METHODS: Transcription activator-like effector nucleases (TALEN) technology was used to generate mutant for tmem67, the homolog of the mammalian causative gene for Meckel syndrome type 3 (MKS3). Classic 2D and optical-clearing 3D imaging of an isolated adult zebrafish kidney were used to examine cystic and ciliary phenotypes. A hypomorphic mtor strain or rapamycin was used to inhibit mTOR activity. RESULTS: Adult tmem67 zebrafish developed progressive mesonephric cysts that share conserved features of mammalian cystogenesis, including a switch of cyst origin with age and an increase in proliferation of cyst-lining epithelial cells. The mutants had shorter and fewer distal single cilia and greater numbers of multiciliated cells (MCCs). Absence of a single cilium preceded cystogenesis, and expansion of MCCs occurred after pronephric cyst formation and was inversely correlated with the severity of renal cysts in young adult zebrafish, suggesting a primary defect and an adaptive action, respectively. Finally, the mutants exhibited hyperactive mTOR signaling. mTOR inhibition ameliorated renal cysts in both the embryonic and adult zebrafish models; however, it only rescued ciliary abnormalities in the adult mutants. CONCLUSIONS: Adult zebrafish tmem67 mutants offer a new vertebrate model for renal cystic diseases, in which cilia morphology can be analyzed at a single-nephron resolution and mTOR inhibition proves to be a candidate therapeutic strategy.

19.
J Appl Clin Med Phys ; 23(3): e13534, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35049118

RESUMO

AIM: The aim of this work was twofold. (1) To investigate and present a comparison between EBT3 and EBT-XD in terms of postirradiation color changes. (2) Create an automated workflow to allow radiochromic film (EBT3/XD) to be scanned and converted to dose accurately at any postirradiation time. MATERIALS AND METHODS: Ten GafChromic EBT-XD calibration films were exposed in 2 Gy increments up to 18 Gy. Calibrates were then scanned at 5-min intervals postirradiation over 24 h using an AutoHotKey script, resulting in 288 TIFF images. Following the 24-h scanning period, a MATLAB script was used to automatically read the tiff images and create a series of 288 calibration curves distinct in time which is termed as the "Temporal Calibration Model" (TCM). The model is saved as a series of polynomial fit coefficients to net optical density as a function of dose, timestamped in 5-min increments. Ten patient-specific film measurements (5 × EBT-XD and 5 × EBT3) were then carried out and scanned using the same 5-min scan intervals from 5 min postirradiation to 24 h postirradiation. The TCM was then automatically applied using eFilmQA software to convert the patient-specific QA films to dose by applying the relevant calibration curve from the TCM, corresponding to the arbitrary postirradiation time that the film was scanned. Each dose plane at postirradiation scan intervals of 5 min up to 20 h was then compared to the ground-truth dose plane using gamma analysis. RESULTS: Gamma pass rates using the TCM at time t, normalized to the pass rate after 20 h postirradiation, were found to have a maximum coefficient of variation of 3% over any postirradiation time. Conversely, not using the TCM resulted in coefficients of variation of up to 39%. Clinical implementation of this method showed an average accuracy of 2.8% when comparing the clinical result to the TCM result. CONCLUSIONS: We have developed a methodology that allows radiochromic film to be accurately used as a dosimeter at any arbitrary scan postirradiation time, whereas previously, waiting periods of 16-24 h before readout were needed to ensure the postirradiation changes had stabilized. The creation of a TCM can enable results from radiochromic film measurements to be obtained quickly postirradiation. Using a conventional single calibration curve generated at 20 h postirradiation can result in gamma pass-rate difference of up to 75% for measurement films scanned at a much shorter postirradiation time.


Assuntos
Dosimetria Fotográfica , Dosímetros de Radiação , Algoritmos , Calibragem , Dosimetria Fotográfica/métodos , Humanos , Software
20.
Angew Chem Int Ed Engl ; 61(44): e202210695, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36106475

RESUMO

Supramolecular polymers (SPs) exhibit intriguing benefits in functional soft materials due to their dynamic bonding feature. However, most SPs can only exist in the solution state and fail to form bulk materials, which limits their applications. Here, we report the fabrication of semi-solid bulk SP materials by using polyoxometalate (POM) nanoclusters as supramolecular cross-linkers to solidify a deep eutectic solvent (DES). The abundant protons and strong hydrogen bonds afforded by POMs enable these SP materials as superprotonic conductive electrolytes with sufficient mechanical strength, showing a proton conductivity more than 1×10-4  S cm-1 and a breaking strength exceeding 1 MPa at room temperature. Moreover, the thermodynamic reversibility of the SP electrolytes allows them to form a stable electrode-electrolyte interface by a facile melt-infiltration strategy upon mild heating, which leads to improved performance in supercapacitors. This work presents an innovative DES/POM hybrid system as a promising platform to develop functional supramolecular materials for energy and electronic applications.

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