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Ammonia is a product of amino acid metabolism that accumulates in the blood of patients with cirrhosis and plays a pivotal role in the pathogenesis of hepatic encephalopathy (HE). Despite being one of the main drivers of brain dysfunction, for many years international societies stated that increased blood ammonia does not add any diagnostic, staging, or prognostic value for HE in patients with cirrhosis. Nonetheless, in the last decades, evidence is emerging that supports the utility of ammonia for risk stratification, but its role in guiding HE diagnosis, staging, and treatment is unclear and there is equipoise in its use in clinical practice. This review provides the latest evidence on the value of ammonia as a biomarker in patients with cirrhosis. Although correct measurement of ammonia requires disciplined sample collection, it provides extremely useful clinical guidance for the diagnosis of HE, offers prognostic information, and it defines a therapeutic target.
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Amoníaco , Biomarcadores , Encefalopatía Hepática , Cirrosis Hepática , Humanos , Amoníaco/sangre , Cirrosis Hepática/sangre , Cirrosis Hepática/diagnóstico , Biomarcadores/sangre , Encefalopatía Hepática/sangre , Encefalopatía Hepática/diagnóstico , Encefalopatía Hepática/etiología , Pronóstico , Valor Predictivo de las PruebasRESUMEN
The electrochemical nitrogen reduction reaction (eNRR) has emerged as a promising strategy for green ammonia synthesis. However, it suffers unsatisfactory reaction performance owing to the low aqueous solubility of N2 in aqueous solution, the high dissociation energy of N≡N, and the unavoidable competing hydrogen evolution reaction (HER). Herein, a MIL-53(Fe)@TiO2 catalyst is designed and synthesized for highly efficient eNRR. Relative to simple MIL-53(Fe), MIL-53(Fe)@TiO2 achieves a 2-fold enhancement in the Faradaic efficiency (FE) with an improved ammonia yield rate by 76.5% at -0.1 V versus reversible hydrogen electrode (RHE). After four cycles of electrocatalysis, MIL-53(Fe)@TiO2 can maintain a good catalytic activity, while MIL-53(Fe) exhibits a significant decrease in the NH3 yield rate and FE by 79.8 and 82.3%, respectively. Benefiting from the synergetic effect between TiO2 and MIL-53(Fe) in the composites, Fe3+ ions can be greatly stabilized in MIL-53(Fe) during the eNRR process, which greatly hinders the catalyst deactivation caused by the electrochemical reduction of Fe3+ ions. Further, the charge transfer ability in the interface of composites can be improved, and thus, the eNRR activity is significantly boosted. These findings provide a promising insight into the preparation of efficient composite electrocatalysts.
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BACKGROUND & AIMS: The Baveno VII consensus recommends that spleen stiffness measurement (SSM) ≤40 kPa is safe for ruling out high-risk varices (HRVs) and avoiding endoscopic screening in patients who do not meet the Baveno VI criteria. This study aimed to validate the performance of the Baveno VII algorithm in individuals with HBV-related cirrhosis. METHODS: Consecutive individuals with HBV-related cirrhosis who underwent liver stiffness measurement (LSM) and SSM - using a 50 Hz shear wave frequency, spleen diameter measurement, and esophagogastroduodenoscopy (EGD) were prospectively enrolled from June 2020. A 100 Hz probe has been adopted for additional SSM assessment since July 2021. RESULTS: From June 2020 to January 2022, 996 patients were screened and 504 were enrolled for analysis. Among the 504 patients in whom SSM was assessed using a 50 Hz probe, the Baveno VII algorithm avoided more EGDs (56.7% vs. 39.1%, p <0.001) than Baveno VI criteria, with a comparable missed HRV rate (3.8% vs. 2.5%). Missed HRV rates were >5% for all other measures: 11.3% for LSM-longitudinal spleen diameter to platelet ratio score, 20.0% for platelet count/longitudinal spleen diameter ratio, and 8.8% for Rete Sicilia Selezione Terapia-hepatitis. SSM@100 Hz was assessed in 232 patients, and the Baveno VII algorithm with SSM@100 Hz spared more EGDs (75.4% vs. 59.5%, p <0.001) than that with SSM@50 Hz, both with a missed HRV rate of 3.0% (1/33). CONCLUSIONS: We validated the Baveno VII algorithm, demonstrating the excellent performance of SSM@50 Hz and SSM@100 Hz in ruling out HRV in individuals with HBV-related cirrhosis. Furthermore, the Baveno VII algorithm with SSM@100 Hz could safely rule out more EGDs than that with SSM@50 Hz. CLINICAL TRIAL NUMBER: NCT04890730. IMPACT AND IMPLICATIONS: The Baveno VII guideline proposed that for patients who do not meet the Baveno VI criteria, SSM ≤40 kPa could avoid further unnecessary endoscopic screening. The current study validated the Baveno VII algorithm using 50 Hz and 100 Hz probes, which both exhibited excellent performance in ruling out HRVs in individuals with HBV-related cirrhosis. Compared with the Baveno VII algorithm with SSM@50 Hz, SSM@100 Hz had a better capability to safely rule out unnecessary EGDs. Baveno VII algorithm will be a practical tool to triage individuals with cirrhosis in future clinical practice.
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Diagnóstico por Imagen de Elasticidad , Várices Esofágicas y Gástricas , Várices , Humanos , Virus de la Hepatitis B , Cirrosis Hepática/diagnóstico , AlgoritmosRESUMEN
The acute-on-chronic liver failure (ACLF) development is highly dynamic. Currently, no satisfactory algorithm identifies patients with HBV at risk of this complication. The aim of the study was to characterize ACLF development in hospitalized HBV-related patients without previous decompensation and to test the performance of traditional prognostic models in ruling out ACLF development within 28 days on admission we conducted a cohort study. Two multi-center cohorts with hospitalized HBV-related previous compensated patients were analyzed. Performances of MELD, MELD-Na, CLIF-C AD, and CLIF-C ACLF-D in ruling out ACLF development within 28 days were compared and further validated by ROC analyses. In the derivation cohort (n = 892), there were 102 patients developed ACLF within 28 days, with profound systemic inflammatory levels and higher 28-day mortality rate (31.4% vs. 1.0%) than those without ACLF development. The MELD score (cut-off = 18) achieved acceptable missing rate (missed/total ACLF development) at 2.9%. In the validation cohort (n = 1656), the MELD score (<18) was able to rule out ACLF development within 28 days with missing rate at 3.0%. ACLF development within 28 days were both lower than 1% (0.6%, derivation cohort; 0.5%, validation cohort) in patients with MELD < 18. While in patients with MELD ≥ 18, 26.6% (99/372, derivation cohort) and 17.8% (130/732, validation cohort) developed into ACLF within 28 days, respectively. While MELD-Na score cut-off at 20 and CLIF-AD score cut-off at 42 did not have consistent performance in our two cohorts. MELD < 18 was able to safely rule out patients with ACLF development within 28 days in HBV-related patients without previous decompensation, which had a high 28-day mortality.
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Insuficiencia Hepática Crónica Agudizada , Hepatitis B , Humanos , Estudios de Cohortes , Pacientes Internos , Hepatitis B/complicaciones , Hepatitis B/epidemiología , Curva ROC , Pronóstico , Estudios RetrospectivosRESUMEN
BACKGROUND: Current vital statistics of birth population and neonatal outcome in China lacked information and definition of deaths at delivery and during hospitalization, especially for extreme preterm (EPT) birth. This study aims to delineate the prevalence of neonatal hospitalization, neonatal and infant mortality rates (NMR, IMR) and associated perinatal risks based on all livebirths in Huai'an, an evolving sub-provincial region in eastern China. METHODS: This retrospective cohort study established a comprehensive database linking information of whole regional livebirths and neonatal hospitalization in 2015, including deaths at delivery and EPT livebirths. The primary outcomes were NMR and IMR stratified by gestational age (GA) and birthweight (BW) with 95% confidence intervals. Causes of the neonatal and infant deaths were categorized according to the International Statistical Classification of Diseases 10th version, and population attributable fractions of GA and BW strata were analyzed. Perinatal risks of infant mortalities in continuum periods were estimated by Cox regression models. RESULTS: Among the whole livebirth population (59056), 7960 were hospitalized (prevalence 13.5%), with 168 (2.8) in-hospital deaths. The NMR was 3.6 (3.2, 4.1) and IMR 4.9 (1.4, 4.5), with additionally 35 (0.6) deaths at delivery. The major causes of infant deaths were perinatal conditions (2.6, mainly preterm-related), congenital anomalies (1.5), sudden unexpected death in infancy (0.6) and other causes (0.2). The deaths caused by preterm and low BW (LBW) accounted for 50% and 40% of NMR and IMR, with 20-30% contributed by EPT or extremely LBW, respectively. Multivariable Cox regression analysis revealed that peripartum factors and LBW strata had strong association with early- and late-neonatal deaths, whereas those of GA < 28 weeks were highly associated with postneonatal deaths. Congenital anomalies and neonatal hospitalization remained high death risks over the entire infancy, whereas maternal co-morbidities/complications were modestly associated with neonatal but not postneonatal infant mortality. CONCLUSIONS: The NMR, IMR, major causes of deaths and associated perinatal risks in continuum periods of infancy, denote the status and quality improvement of the regional perinatal-neonatal care associated with socioeconomic development. The study concept, applicability and representativeness may be validated in other evolving regions or countries for genuine comparison and better maternal-infant healthcare.
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Muerte del Lactante , Mortalidad Infantil , Peso al Nacer , China/epidemiología , Estudios de Cohortes , Femenino , Humanos , Lactante , Recién Nacido , Embarazo , Estudios RetrospectivosRESUMEN
The hydrodynamic properties of a squirmer type of self-propelled particle in a simple shear flow are investigated using the immersed boundary-lattice Boltzmann method in the range of swimming Reynolds number 0.05 ≤ Res ≤ 2.0, flow Reynolds number 40 ≤ Rep ≤ 160, blocking rate 0.2 ≤ κ ≤ 0.5. Some results are validated by comparing with available other results. The effects of Res, Rep and κ on the hydrodynamic properties of squirmer are discussed. The results show that there exist four distinct motion modes for the squirmer, i.e., horizontal mode, attractive oscillation mode, oscillation mode, and chaotic mode. Increasing Res causes the motion mode of the squirmer to change from a constant tumbling near the centerline to a stable horizontal mode, even an oscillatory or appealing oscillatory mode near the wall. Increasing the swimming intensity of squirmer under the definite Res will induce the squirmer to make periodic and stable motion at a specific distance from the wall. Increasing Rep will cause the squirmer to change from a stable swimming state to a spiral motion or continuous rotation. Increasing κ will strengthen the wall's attraction to the squirmer. Increasing swimming intensity of squirmer will modify the strength and direction of the wall's attraction to the squirmer if κ remains constant.
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Irisin, the cleaved form of the fibronectin type III domain containing 5 (FNDC5) protein, is involved in metabolism and inflammation. Recent findings indicated that irisin participated in cardiovascular physiology and pathology. In this study, we investigated the effects of FNDC5/irisin on diabetic cardiomyopathy (DCM) in type 2 diabetic db/db mice. Downregulation of myocardial FNDC5/irisin protein expression and plasma irisin levels was observed in db/db mice compared to db/+ controls. Moreover, echocardiography revealed that db/db mice exhibited normal cardiac systolic function and impaired diastolic function. Adverse structural remodeling, including cardiomyocyte apoptosis, myocardial fibrosis, and cardiac hypertrophy were observed in the hearts of db/db mice. Sixteen-week-old db/db mice were intramyocardially injected with adenovirus encoding FNDC5 or treated with recombinant human irisin via a peritoneal implant osmotic pump for 4 weeks. Both overexpression of myocardial FNDC5 and exogenous irisin administration attenuated diastolic dysfunction and cardiac structural remodeling in db/db mice. Results from in vitro studies revealed that FNDC5/irisin protein expression was decreased in high glucose (HG)/high fat (HF)-treated cardiomyocytes. Increased levels of inducible nitric oxide synthase (iNOS), NADPH oxidase 2 (NOX2), 3-nitrotyrosine (3-NT), reactive oxygen species (ROS), and peroxynitrite (ONOO-) in HG/HF-treated H9C2 cells provided evidence of oxidative/nitrosative stress, which was alleviated by treatment with FNDC5/irisin. Moreover, the mitochondria membrane potential (ΔΨm) was decreased and cytochrome C was released from mitochondria with increased levels of cleaved caspase-3 in HG/HF-treated H9C2 cells, indicating the presence of mitochondria-dependent apoptosis, which was partially reversed by FNDC5/irisin treatment. Mechanistic studies showed that activation of integrin αVß5-AKT signaling and attenuation of oxidative/nitrosative stress were responsible for the cardioprotective effects of FNDC5/irisin. Therefore, FNDC5/irisin mediates cardioprotection in DCM by inhibiting myocardial apoptosis, myocardial fibrosis, and cardiac hypertrophy. These findings implicate that FNDC5/irisin as a potential therapeutic intervention for DCM, especially in type 2 diabetes mellitus (T2DM).
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Cardiotónicos/administración & dosificación , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Cardiomiopatías Diabéticas/sangre , Cardiomiopatías Diabéticas/tratamiento farmacológico , Fibronectinas/administración & dosificación , Estrés Nitrosativo/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores de Vitronectina/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Cardiomegalia/prevención & control , Cardiotónicos/sangre , Modelos Animales de Enfermedad , Fibronectinas/sangre , Fibronectinas/genética , Masculino , Ratones , Mitocondrias/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Proteínas Recombinantes/administración & dosificación , Resultado del Tratamiento , Remodelación Ventricular/efectos de los fármacosRESUMEN
BACKGROUND AND AIM: Tri-typing of acute-on-chronic liver failure (ACLF), as proposed by the World Gastroenterology Organization (WGO), has not been validated in patients infected with hepatitis B virus (HBV). We aim to compare the three types of ACLF patients in clinic characteristics. METHODS: Hospitalized ACLF patients with chronic hepatitis B from five hepatology centers were retrospectively selected and grouped according to the WGO classification. For each group, we investigated laboratory tests, precipitating events, organ failure, and clinical outcome. RESULTS: Compared with type-B (n = 262, compensated cirrhosis) and type-C (n = 129, decompensated cirrhosis) ACLF, type-A patients (n = 195, non-cirrhosis) were associated with a younger age, the highest platelet counts, the highest aminotransferase levels, and the most active HBV replications. HBV reactivation were more predominant in type-A, while bacterial infections in type-B and type-C ACLF cases. Liver failure (97.4%) and coagulation failure (86.7%) were most common in type-A compared with type-B or type-C ACLF patients. Kidney failure was predominantly identified in type-C subjects (41.9%) and was highest (23/38, 60.5%) in grade 1 ACLF patients. Furthermore, type-C ACLF showed the highest 28-day (65.2%) and 90-day (75.3%) mortalities, compared with type-A (48.7% and 54.4%, respectively) and type-B (48.4% and 62.8%, respectively) ACLF cases. Compared with type-A (11.7%) ACLF patients, the increased mortality from 28 to 90 days was higher in type-B (31.6%) and type-C (37.5%). CONCLUSION: Tri-typing of HBV-related ACLF in accordance with the WGO definition was able to distinguish clinical characteristics, including precipitating events, organ failure, and short-term prognosis in ACLF patients.
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Insuficiencia Hepática Crónica Agudizada/clasificación , Insuficiencia Hepática Crónica Agudizada/etiología , Gastroenterología/organización & administración , Hepatitis B Crónica/complicaciones , Insuficiencia Hepática Crónica Agudizada/diagnóstico , Insuficiencia Hepática Crónica Agudizada/mortalidad , Adulto , Factores de Edad , China , Femenino , Virus de la Hepatitis B/fisiología , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Pronóstico , Estudios Retrospectivos , Centros de Atención Terciaria , Transaminasas/sangre , Replicación ViralRESUMEN
BACKGROUND: Despite 15-17 millions of annual births in China, there is a paucity of information on prevalence and outcome of preterm birth. We characterized the outcome of preterm births and hospitalized preterm infants by gestational age (GA) in Huai'an in 2015, an emerging prefectural region of China. METHODS: Of 59,245 regional total births, clinical data on 2651 preterm births and 1941 hospitalized preterm neonates were extracted from Huai'an Women and Children's Hospital (HWCH) and non-HWCH hospitals in 2018-2020. Preterm prevalence, morbidity and mortality rates were characterized and compared by hospital categories and GA spectra. Death risks of preterm births and hospitalized preterm infants in the whole region were analyzed with multivariable Poisson regression. RESULTS: The prevalence of extreme, very, moderate, late and total preterm of the regional total births were 0.14, 0.53, 0.72, 3.08 and 4.47%, with GA-specific neonatal mortality rates being 44.4, 15.8, 3.7, 1.5 and 4.3%, respectively. There were 1025 (52.8% of whole region) preterm admissions in HWCH, with significantly lower in-hospital death rate of inborn (33 of 802, 4.1%) than out-born (23 of 223, 10.3%) infants. Compared to non-HWCH, three-fold more neonates in HWCH were under critical care with higher death rate, including most extremely preterm infants. Significantly all-death risks were found for the total preterm births in birth weight < 1000 g, GA < 32 weeks, amniotic fluid contamination, Apgar-5 min < 7, and birth defects. For the hospitalized preterm infants, significantly in-hospital death risks were found in out-born of HWCH, GA < 32 weeks, birth weight < 1000 g, Apgar-5 min < 7, birth defects, respiratory distress syndrome, necrotizing enterocolitis and ventilation, whereas born in HWCH, antenatal glucocorticoids, cesarean delivery and surfactant use decreased the death risks. CONCLUSIONS: The integrated data revealed the prevalence, GA-specific morbidity and mortality rate of total preterm births and their hospitalization, demonstrating the efficiency of leading referral center and whole regional perinatal-neonatal network in China. The concept and protocol should be validated in further studies for prevention of preterm birth.
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Edad Gestacional , Maternidades/estadística & datos numéricos , Atención Perinatal/estadística & datos numéricos , Mortalidad Perinatal , Nacimiento Prematuro/epidemiología , China/epidemiología , Femenino , Mortalidad Hospitalaria , Hospitalización/estadística & datos numéricos , Maternidades/organización & administración , Humanos , Recién Nacido , Masculino , Atención Perinatal/organización & administración , Embarazo , Nacimiento Prematuro/prevención & control , PrevalenciaRESUMEN
Acute liver failure (ALF) is a severe consequence of abrupt hepatocyte injury and has lethal outcomes. Three toll-like receptor agonists, including polyinosinic-polycytidylic acid (poly(I:C)), lipopolysaccharide (LPS), and cytosine-phosphate-guanine (CpG) DNA, cause acute and severe hepatitis, respectively, in D-galactosamine (D-GalN)-sensitized mice. However, the molecular differences among three ALF models (LPS/D-GalN, poly(I:C)/D-GalN, and CpG DNA/D-GalN), are unclear. Here, tandem mass tag based quantitative proteomic analyses of three ALF mouse models are performed. 52 common differentially expressed proteins (DEPs) are identified, in three ALF groups, compared to the control. Gene ontology analyses show that among the common DEPs, ten proteins are involved in immune system process, and 39 proteins in metabolic process. Among 80,195, and 23 specifically-expressed proteins in poly(I:C)/D-GalN, LPS/D-GalN, and CpG DNA/D-GalN groups, LPS/D-GalN-specific proteins are mostly distributed in the endoplasmic reticulum and more enriched in metabolic pathways, whereas poly (I:C)/D-GalN-specific proteins are mainly in the membrane and CpG DNA/D-GalN-specific proteins are related to the ribosome structural composition. In conclusion, the common and specific DEPs in three ALF mouse models at molecular level are identified; and determined a close-to-complete reference map of mouse liver proteins which will be useful for clinical diagnosis and treatment of liver failure in humans.
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Fallo Hepático Agudo/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Receptores Toll-Like/agonistas , Animales , Modelos Animales de Enfermedad , Galactosamina/farmacología , Lipopolisacáridos/farmacología , Fallo Hepático Agudo/inducido químicamente , Ratones Endogámicos C57BL , Proteínas/análisis , Proteínas/metabolismo , Proteómica/métodos , Espectrometría de Masas en Tándem , Receptores Toll-Like/metabolismoRESUMEN
BACKGROUND: Acute-on-chronic liver failure (ACLF) is a syndrome characterized by profound disrupted coagulation and fibrinolysis. Fibrinolytic marker D-dimer is increased in critically ill patients with cirrhosis which is associated with poorer prognosis. We aim to determine the potential association of D-dimer with the 28-day mortality in ACLF patients. METHODS: In a single center retrospective study performed in China, we collected data of 115 patients with ACLF from October 1, 2012 to December 31, 2016. We investigated correlations between D-dimer and other laboratory tests and prognostic scores. The relationship between D-dimer and 28-day mortality was explored by smoothing plot with an adjustment for potential confounders. Logistic regression analyses with crude and adjusted models were performed to explore the association of D-dimer with 28-day mortality in ACLF patients. RESULTS: In ACLF patients, D-dimer at admission was correlated with all prognostic scores (MELD-Na: r = 0.385, P < 0.001; CLIF-C ADs: r = 0.443, P < 0.001; CLIF-C ACLFs: r = 0.375, P < 0.001). A nonlinear relation between D-dimer and 28-day mortality was found with a turning point at 6.5 mg/L FEU. D-dimer level was independently associated with 28-day mortality with an adjusted odds ratio of [1.4 (1.0-1.9), P = 0.030] as continuous variable and [10.3 (1.3, 81.5), P = 0.028] as a classified variable with the cut-off of 6.5 mg/L FEU. An elevated D-dimer within the following 10 days also tended to be associated with higher risk of 28-day mortality [OR: 27.5 (0.9, 814.9), P = 0.055]. CONCLUSIONS: Elevated D-dimer levels was associated with increased risk of 28-day mortality in patients with ACLF in China.
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Insuficiencia Hepática Crónica Agudizada/sangre , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Insuficiencia Hepática Crónica Agudizada/mortalidad , Adulto , Biomarcadores/sangre , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios RetrospectivosRESUMEN
BACKGROUND: The objective of this survey was to explore the association between pregnancy complications and perinatal outcome from regionally total birth population. METHODS: In this prospectively collected data of complete birth registries from all level I-III hospitals in Huai'an in 2015, perinatal morbidity and mortality in relation to pregnancy complications and perinatal outcome were analyzed using international definitions. The results were compared with that of 2010 survey in the same region. RESULTS: Of 59,424 total births in the hospitals of level I (n = 85), II (16) and III (6), delivery rate was 30.4, 40.1 and 29.5%, and rates of pregnancy complications were 12.9, 9.8 and 21.1% (average 14.1%), with antenatal corticosteroids rate in < 37 gestational weeks being 17.3, 31.0 and 39.9% (mean 36.6%), respectively. The preterm birth rate was 0.6, 2.7 and 9.5% (mean 4.06%), and the composite rate of fetal death, stillbirth, and death immediately after delivery was 0.1, 0.4 and 0.6%, respectively. By multivariable logistic regression analysis, congenital anomalies, low Apgar scores, multi-pregnancy and amniotic fluid contamination were risk factors of adverse perinatal outcomes. Despite a higher rate of pregnancy complications than in 2010 survey, perinatal and neonatal mortality continued to fall, in particular in very preterm births. The high cesarean delivery rate in non-medically indicated cases remained a challenge. CONCLUSIONS: Our regional birth-population data in 2015 revealed a robust and persistent improvement in the perinatal care and management of high risk pregnancies and deliveries, which should enable more studies using similar concept and protocol for vital statistics to verify the reliability and feasibility.
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Parto Obstétrico/mortalidad , Atención Perinatal/tendencias , Mortalidad Perinatal/tendencias , Complicaciones del Embarazo/mortalidad , Embarazo de Alto Riesgo , Adulto , China , Femenino , Humanos , Recién Nacido , Modelos Logísticos , Embarazo , Sistema de Registros , Factores de RiesgoRESUMEN
Understanding the kinetics of shock-compressed SiO2 is of great importance for mitigating optical damage for high-intensity lasers and for understanding meteoroid impacts. Experimental work has placed some thermodynamic bounds on the formation of high-pressure phases of this material, but the formation kinetics and underlying microscopic mechanisms are yet to be elucidated. Here, by employing multiscale molecular dynamics studies of shock-compressed fused silica and quartz, we find that silica transforms into a poor glass former that subsequently exhibits ultrafast crystallization within a few nanoseconds. We also find that, as a result of the formation of such an intermediate disordered phase, the transition between silica polymorphs obeys a homogeneous reconstructive nucleation and grain growth model. Moreover, we construct a quantitative model of nucleation and grain growth, and compare its predictions with stishovite grain sizes observed in laser-induced damage and meteoroid impact events.
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In this work, the ß-galactosidase from Enterobacter cloacae B5 (BgaB5) exhibited excellent transglycosylation activity toward tyrosol (p-hydroxyphenethyl alcohol) when using lactose as the glycosyl donor, generating a series of tyrosol glycosides with potential pharmacological properties. The effects of substrate concentration, temperature, pH, and reaction time on the transglycosylation reaction catalyzed by the enzyme BgaB5 were studied in detail. Three tyrosol derivatives were produced in a total high yield of 50.0% when incubating the enzyme with 250 mM tyrosol and 1000 mM lactose (pH 7.5) at 50 °C for 5 min. These derivatives were subsequently purified by column chromatography and preparative thin-layer chromatography. MS analysis of the purified compounds suggested one monogalactoside (M r 300) and two digalactoside derivatives (M r 462). The following NMR analysis further identified them to be p-hydroxyphenethyl ß-D-galactopyranoside, p-hydroxyphenethyl ß-D- galactopyranosyl-(1 â 3')-ß-D-galactopyranoside, and p-hydroxyphenethyl ß-D- galactopyranosyl-(1 â 6')-ß-D-galactopyranoside, respectively. The yield of the tyrosol monogalactoside which was known to possess potent bioactivities reached 39.4%, higher than other enzymatic yields reported so far. The two digalactosides, which were expected to have potential applications for novel drug screening and discovery, were artificially obtained with 10.6% yield for the first time.
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Antioxidantes/metabolismo , Enterobacter cloacae/enzimología , Galactósidos/biosíntesis , Alcohol Feniletílico/análogos & derivados , beta-Galactosidasa/metabolismo , Antioxidantes/química , Biocatálisis , Cromatografía en Capa Delgada , Enterobacter cloacae/genética , Enterobacter cloacae/metabolismo , Galactosa/metabolismo , Cinética , Lactosa/metabolismo , Espectroscopía de Resonancia Magnética , Alcohol Feniletílico/química , Alcohol Feniletílico/metabolismo , Especificidad por Sustrato , beta-Galactosidasa/genéticaRESUMEN
In this study, the binding mode of nobiletin (NOB) with pepsin was investigated by spectroscopic and molecular docking methods. NOB can interact with pepsin to form a NOB-pepsin complex. The binding constant, number of binding sites and thermodynamic parameters were measured, which indicated that NOB could spontaneously bind with pepsin through hydrophobic and electrostatic forces with one binding site. Molecular docking results revealed that NOB bound into the pepsin cavity. Synchronous and three-dimensional fluorescence spectra results provide data concerning conformational and some micro-environmental changes of pepsin. Furthermore, the binding of NOB can inhibit pepsin activity in vitro. The present study provides direct evidence at a molecular level to show that NOB could induce changes in the enzyme pepsin structure and function.
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Flavonas/química , Simulación del Acoplamiento Molecular , Pepsina A/química , Estructura Molecular , Espectrometría de Fluorescencia , Espectrofotometría UltravioletaRESUMEN
This paper reviews the recent research and development of multifunctional nanostructured materials for multimodal imaging and therapy. The biomedical applications for multifunctional imaging, diagnosis and therapy are discussed for several nanostructured materials such as polymeric nanoparticles, magnetic nanoparticles, gold nanomaterials, carbon materials, quantum dots and silica nanoparticles. Due to the unique features of nanostructured materials including the large surface area, structural diversity, multifunctionality, and long circulation time in blood, these materials have emerged as attractive preferences for optimized therapy. Multimodal imaging can be introduced to nanostructured materials for precise and fast diagnosis of cancer, which overcomes the shortcoming of single-imaging modality. Meanwhile, nanostructured materials can be also used to deliver therapeutic agents to the disease site in order to accomplish multimodal imaging and simultaneous diagnosis and therapy.
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Imagen Molecular/métodos , Terapia Molecular Dirigida/métodos , Imagen Multimodal/métodos , Nanopartículas/química , Nanopartículas/uso terapéutico , Neoplasias/diagnóstico , Neoplasias/terapia , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , HumanosRESUMEN
Objective: Based on real-world research, we aimed to evaluate the effectiveness and economy of recombinant human thrombopoietin (rhTPO) and recombinant human interleukin 11 (rhIL-11) in the treatment of cancer therapy induced thrombocytopenia (CTIT). Methods: We retrospectively collected clinical data of patients with CTIT who were treated with rhTPO or rhIL-11 in a single cancer hospital from January 2020 to December 2021. Propensity score matching (PSM) was applied to eliminate confounding factors. The measurements of effectiveness analysis were the platelet compliance rate, days of medication, days of compliance, highest platelet count after medication, platelet count elevation before and after medication, and the lowest platelet count after next-cycle cancer therapy. The economic evaluation was performed according to the results of the effectiveness evaluation. At the same time, patients were stratified according to type of tumor and grade of thrombocytopenia for subgroup analysis. Results: A total of 262 patients were collected and 174 patients were enrolled after PSM, 87 in the rhTPO group and 87 in the rhIL-11 group. In all patients, there were no significant differences in the platelet compliance rate, mean days of medication, median days of compliance, median highest platelet count after medication, and the median platelet count elevation before and after medication between the two groups (p > 0.05), but the median lowest platelet count after next-cycle cancer therapy in the rhTPO group was lower than that in the rhIL-11 group (p = 0.014). The subgroup analysis showed that the rhTPO group had longer mean days of medication than the rhIL-11 group in patients with hematological malignancies (p = 0.042), and a lower median lowest platelet count after next-cycle cancer therapy in patients with grade I/II thrombocytopenia than rhIL-11 group (p = 0.022), with no significant difference in other outcome indicators (p > 0.05). As there was no statistically significant difference in platelet compliance rate between the two groups, the cost-minimization analysis showed that the rhIL-11 group had lower treatment costs than the rhTPO group. Conclusion: RhTPO and rhIL-11 showed similar effectiveness in the treatment of CTIT, but rhIL-11 was more advantageous in economic cost.
RESUMEN
Neuronal apoptosis is crucial in the pathophysiology of ischemic stroke (IS), albeit its underly24ing mechanism remaining elusive. Investigating the mechanism of neuronal apoptosis in the context of IS holds substantial clinical value for enhancing the prognosis of IS patients. Notably, the MRPS9 gene plays a pivotal role in regulating mitochondrial function and maintaining structural integrity. Utilizing bioinformatic tactics and the extant gene expression data related to IS, we conducted differential analysis and weighted correlation network analysis (WGCNA) to select important modules. Subsequent gene interaction analysis via the STRING website facilitated the identification of the key gene-mitochondrial ribosomal protein S9 (MRPS9)-that affects the progression of IS. Moreover, possible downstream signaling pathways, namely PI3K/Akt/mTOR, were elucidated via Kyoto Encyclopedia of Gene and Genomes (KEGG) and Gene Ontology (GO) pathway analysis. Experimental models were established utilizing oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro and middle cerebral artery occlusion/reperfusion (MCAO/R) in mice. Changes in gene and protein expression, as well as cell proliferation and apoptosis, were monitored through qPCR, WB, CCK8, and flow cytometry. An OGD/R cell model was further employed to investigate the role of MRPS9 in IS post transfusion of MRPS9 overexpression plasmids into cells. Further studies were conducted by transfecting overexpressed cells with PI3K/Akt/mTOR signaling pathway inhibitor LY294002 to unveil the mechanism of MRPS9 in IS. Bioinformatic analysis revealed a significant underexpression of MRPS9 in ischemic stroke patients. Correspondingly, in vitro experiments with HN cells subjected to OGD/R treatment demonstrated a marked reduction in MRPS9 expression, accompanied by a decline in cell viability, and an increase cell apoptosis. Notably, the overexpression of MRPS9 mitigated the OGD/R-induced decrease in cell viability and augmentation of apoptosis. In animal models, MRPS9 expression was significantly lower in the MCAO/R group compared to the sham surgery group. Further, the KEGG pathway analysis associated MRPS9 expression with the PI3K/Akt/mTOR signaling pathway. In cells treated with the specific PI3K/Akt/mTOR inhibitor LY294002, phosphorylation levels of Akt and mTOR were decreased, cell viability decreased, and apoptosis increased compared to the MRPS9 overexpression group. These findings collectively indicate that MRPS9 overexpression inhibits PI3K/Akt/mTOR pathway activation, thereby protecting neurons from apoptosis and impeding IS progression. However, the PI3K/Akt/mTOR inhibitor LY294002 is capable of counteracting the protective effect of MRPS9 overexpression on neuronal apoptosis and IS. Our observations underscore the potential protective role of MRPS9 in modulating neuronal apoptosis and in attenuating the pathophysiological developments associated with IS. This is achieved through the regulation of the PI3K/Akt/mTOR pathway. These insights forge new perspectives and propose novel targets for the strategic diagnosis and treatment of IS.