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1.
J Clin Ultrasound ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39282883

RESUMEN

BACKGROUND: This research aims to summarize the ultrasound features and pregnancy outcomes of incarceration of the gravid uterus (IGU), providing a basis for clinical management. METHODS: A retrospective cohort study was conducted on pregnant patients with IGU at Hunan Provincial Maternal and Child Health Care Hospital in China, spanning from September 30, 2016, to May 31, 2024. Data on maternal age, parity, medical history, risk factors, gestational age, clinical manifestations, ultrasound examination, treatment methods, time, and method for terminating pregnancy, and pregnancy outcomes were collected. We compared cases diagnosed before and after 20 gestational weeks. RESULTS: During the study period, 13 pregnant women were diagnosed with IGU, and 140 162 deliveries were recorded at our hospital. Two cases were referred from other hospitals and did not deliver in our hospital. Accordingly, the incidence of IGU was 0.08‰ (11/140, 162). The most prevalent risk factor for IGU was previous abdominal or pelvic surgery (61.54%, 8/13). Dysuria or even urinary retention was the primary symptom (38.46%, 5/13). Spontaneous resolution occurred in only one case (7.69%). All cases were detected using prenatal ultrasound examination with typical characteristics, including a retroverted uterus and the fundus located behind the cervix. No statistically significant differences between the two comparison groups were found in successful uterine reduction (p > 0.05). CONCLUSION: The definition of IGU should include symptomatic cases of any gestational age. Despite a low prevalence of this pregnancy complication, the overall prognosis of IGU is good. In the absence of severe symptoms, regular monitoring may be an option. Typical ultrasound imaging features enable a definitive diagnosis of IGU.

2.
Med ; 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39094582

RESUMEN

BACKGROUND: A dramatic increase in fetal situs inversus diagnoses by ultrasound in the months following the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surge of December 2022 in China led us to investigate whether maternal SARS-CoV-2 exposure could be associated with elevated risk of fetal situs inversus. METHODS: In this multi-institutional, hospital-based, matched case-control study, we investigated pregnant women who underwent ultrasonographic fetal biometric assessment at gestational weeks 20-24 at our hospitals. Each pregnant woman carrying a situs inversus fetus was randomly matched with four controls based on the date of confinement. Relevant information, including SARS-CoV-2 infection, and other potential risk factors were collected. Conditional logistic regression was used to test possible associations between fetal situs inversus and SARS-CoV-2 infection at different gestational weeks as well as individual risk factors. FINDINGS: A total of 52 pregnant women diagnosed with fetal situs inversus between January 1 and October 31, 2023 and 208 matched controls with normal fetuses were enrolled. We found no association between an increased risk of fetal situs inversus with gestational SARS-CoV-2 infection or with other risk factors. However, fetal situs inversus was significantly associated with SARS-CoV-2 infection specifically in gestational weeks 4-6 (adjusted odds ratio [aOR] 6.54 [95% confidence interval 1.76-24.34]), but not with infection at other gestational ages, after adjusting for covariates. CONCLUSIONS: Increased risk of fetal situs inversus is significantly associated with maternal SARS-CoV-2 infection at gestational weeks 4-6, corresponding to the fetal developmental window for visceral lateralization in humans. FUNDING: National Key R&D Program of China, etc.

3.
Med Phys ; 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39190783

RESUMEN

BACKGROUND: Periventricular-intraventricular hemorrhage can lead to posthemorrhagic ventricular dilatation or even posthemorrhagic hydrocephalus if not detected promptly. Sequential cranial ultrasound scans are typically used for their diagnoses. Nonetheless, manual image audit has numerous disadvantages. PURPOSE: This study aimed to develop a predictive model utilizing modified inception (MI) and high-level feature-guided attention (HFA) modules for predicting neonatal lateral ventricular dilation via ultrasound images. METHODS: The MI modules reduced input data sizes and dimensions, while the HFA modules effectively delved into semantic information through supervision from high-level feature images to low-level feature images. The process facilitated the accurate identification of dilated lateral ventricles. A total of 710 neonates, corresponding to 1420 lateral ventricles, were recruited in this study. Each lateral ventricle was captured in two images, one on the parasagittal plane and the other on the coronal plane. The combination of anterior horn width, ventricular index, thalamo-occipital distance, and ventricular height served as the gold standard. A lateral ventricle would be considered dilatated if any of these four indices exceeded its upper reference value. These lateral ventricles were randomly split into training and testing sets at a 7:3 ratio. We evaluated the validity of our proposed approach and its competitors across the coronal plane, parasagittal plane, and overall performance. We also determined the impact of subjects' baseline characteristics on the overall performance of the proposed approach. Additionally, ablation analyses were conducted to ensure the efficacy of the proposed approach. RESULTS: Our proposed approach achieved the largest Youden index (0.65, 95% CI: 0.58-0.72), DOR (27.11, 95% CI: 15.89-46.26), area under curves (AUC) of receiver operating characteristic curve (ROC) (0.84, 95% CI: 0.80-0.88), and AUC of precision-recall curve (PRC) (0.81, 95% CI: 0.74-0.86) in the overall performance assessment and ablation analyses. Moreover, it boasted the biggest Cramer's V values on the coronal (Cramer's V = 0.488, p < 0.001) and parasagittal (Cramer's V = 0.713, p < 0.001) planes individually. Factors such as left side, male sex, singleton birth, and vaginal delivery were positively correlated with higher performance regarding the proposed algorithm, except for the gestational age. CONCLUSION: This work provides a novel attention optimized algorithm for rapid and accurate ventricular dilatation predictions. It surpasses the traditional algorithms in terms of validity whether concerning the coronal plane, parasagittal plane, or overall performance. The overall performance of algorithms will be influenced by the baseline characteristics of populations.

4.
J Chromatogr A ; 1734: 465289, 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39181093

RESUMEN

This paper introduces a method for determining the specific surface area (SSA) of biomass activated carbon (BAC) using a tracer-based headspace gas chromatography (HS-GC) technique. The method relies on the adsorption equilibrium of methanol on BAC samples at elevated temperature. A mathematical model allows for the calculation of SSA from the methanol signal obtained during the headspace analysis. The results demonstrate high precision (relative standard deviation < 2.44%) and strong accuracy (correlation with the conventional BET-N2 adsorption method, R² = 0.986). This method offers several advantages over traditional techniques, including ease of operation, significant time efficiency, and the the ability to perform batch determinations of SSA, as multiple samples can be processed simultaneously during the phase equilibrium step.


Asunto(s)
Biomasa , Carbón Orgánico , Metanol , Cromatografía de Gases/métodos , Adsorción , Carbón Orgánico/química , Metanol/química , Propiedades de Superficie
5.
Circ Arrhythm Electrophysiol ; 17(7): e012452, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39012929

RESUMEN

BACKGROUND: Aging is one of the most potent risk determinants for the onset of atrial fibrillation (AF). Sirts (sirtuins) have been implicated in the pathogenesis of cardiovascular disease, and their expression declines with aging. However, whether Sirts involved in age-related AF and its underlying mechanisms remain unknown. The present study aims to explore the role of Sirts in age-related AF and delineate the underlying molecular mechanisms. METHODS: Sirt1 levels in the atria of both elderly individuals and aging rats were evaluated using quantitative real-time polymerase chain reaction and Western blot analysis. Mice were engineered to specifically knockout Sirt1 in the atria and right ventricle (Sirt1mef2c/mef2c). Various techniques, such as echocardiography, atrial electrophysiology, and protein acetylation modification omics were employed. Additionally, coimmunoprecipitation was utilized to substantiate the interaction between Sirt1 and RIPK1 (receptor-interacting protein kinase 1). RESULTS: We discerned that among the diverse subtypes of sirtuin proteins, only Sirt1 expression was significantly diminished in the atria of elderly people and aged rats. The Sirt1mef2c/mef2c mice exhibited an enlarged atrial diameter and heightened vulnerability to AF. Acetylated proteomics and cell experiments identified that Sirt1 deficiency activated atrial necroptosis through increasing RIPK1 acetylation and subsequent pseudokinase MLKL (mixed lineage kinase domain-like protein) phosphorylation. Consistently, necroptotic inhibitor necrosulfonamide mitigated atrial necroptosis and diminished both the atrial diameter and AF susceptibility of Sirt1mef2c/mef2c mice. Resveratrol prevented age-related AF in rats by activating atrial Sirt1 and inhibiting necroptosis. CONCLUSIONS: Our findings first demonstrated that Sirt1 exerts significant efficacy in countering age-related AF by impeding atrial necroptosis through regulation of RIPK1 acetylation, highlighting that the activation of Sirt1 or the inhibition of necroptosis could potentially serve as a therapeutic strategy for age-related AF.


Asunto(s)
Fibrilación Atrial , Modelos Animales de Enfermedad , Atrios Cardíacos , Ratones Noqueados , Necroptosis , Proteína Serina-Treonina Quinasas de Interacción con Receptores , Sirtuina 1 , Anciano , Animales , Femenino , Humanos , Masculino , Ratones , Ratas , Acetilación , Factores de Edad , Envejecimiento/metabolismo , Envejecimiento/patología , Fibrilación Atrial/metabolismo , Fibrilación Atrial/genética , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/prevención & control , Fibrilación Atrial/patología , Atrios Cardíacos/metabolismo , Atrios Cardíacos/patología , Atrios Cardíacos/fisiopatología , Ratones Endogámicos C57BL , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Ratas Sprague-Dawley , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Transducción de Señal , Sirtuina 1/metabolismo , Sirtuina 1/genética
6.
J Clin Ultrasound ; 52(6): 737-744, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38662985

RESUMEN

OBJECTIVE: We aimed to analyze the echocardiographic characteristics and pregnancy outcomes for fetuses with premature complete closure of the fetal ductus arteriosus. METHODS: A retrospective analysis was performed for eight cases of premature ductus arteriosus closure diagnosed by prenatal ultrasonography in the Hunan Maternal and Child Health Hospital from July 2019 to August 2022, and the characteristics of fetal echocardiography and pregnancy outcomes of the eight cases were analyzed and summarized. RESULTS: In all cases, the intima of the ductus arteriosus was thickened and occluded, the ductus arteriosus could be seen with slightly hyperechogenic, and no blood flow signal was found in the ductus arteriosus by Doppler ultrasonography. The right heart was enlarged in seven cases, and the whole heart was enlarged in one case. Tricuspid valve regurgitation was observed to different degrees, of which seven cases were severe and one case was moderate. The pulmonary arteries of eight patients had varying degrees of widening. All eight cases were delivered by cesarean section, and one newborn died after follow-up. The prognosis of the other newborns was good. CONCLUSION: The parameters of prenatal echocardiography are helpful for the prognosis of fetuses with premature closure of the ductus arteriosus. Early prenatal detection, close observation, and clinical guidance can be used to select the right time of delivery.


Asunto(s)
Conducto Arterial , Ecocardiografía , Resultado del Embarazo , Ultrasonografía Prenatal , Humanos , Femenino , Embarazo , Estudios Retrospectivos , Ultrasonografía Prenatal/métodos , Adulto , Conducto Arterial/diagnóstico por imagen , Ecocardiografía/métodos , Recién Nacido
7.
Sci Rep ; 14(1): 5351, 2024 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438512

RESUMEN

This study aims at suggesting an end-to-end algorithm based on a U-net-optimized generative adversarial network to predict anterior neck lower jaw angles (ANLJA), which are employed to define fetal head posture (FHP) during nuchal translucency (NT) measurement. We prospectively collected 720 FHP images (half hyperextension and half normal posture) and regarded manual measurement as the gold standard. Seventy percent of the FHP images (half hyperextension and half normal posture) were used to fit models, and the rest to evaluate them in the hyperextension group, normal posture group (NPG), and total group. The root mean square error, explained variation, and mean absolute percentage error (MAPE) were utilized for the validity assessment; the two-sample t test, Mann-Whitney U test, Wilcoxon signed-rank test, Bland-Altman plot, and intraclass correlation coefficient (ICC) for the reliability evaluation. Our suggested algorithm outperformed all the competitors in all groups and indices regarding validity, except for the MAPE, where the Inception-v3 surpassed ours in the NPG. The two-sample t test and Mann-Whitney U test indicated no significant difference between the suggested method and the gold standard in group-level comparison. The Wilcoxon signed-rank test revealed significant differences between our new approach and the gold standard in personal-level comparison. All points in Bland-Altman plots fell between the upper and lower limits of agreement. The inter-ICCs of ultrasonographers, our proposed algorithm, and its opponents were graded good reliability, good or moderate reliability, and moderate or poor reliability, respectively. Our proposed approach surpasses the competition and is as reliable as manual measurement.


Asunto(s)
Mandíbula , Medida de Translucencia Nucal , Humanos , Femenino , Embarazo , Reproducibilidad de los Resultados , Mandíbula/diagnóstico por imagen , Feto/diagnóstico por imagen , Atención Prenatal
8.
J Chromatogr A ; 1721: 464823, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38547679

RESUMEN

This paper reports a method for determining the oil absorption value of inorganic powder based on tracer-assisted headspace gas chromatographic (HS-GC) technique. The method was carried out by adding 25 µL droplet of toluene-Dioctyl Phthalate solution onto the surface of 1.0 g inorganic powder, then sealing the headspace vial and shaking it to make the powder spherical. The amount of toluene that not been adsorbed by inorganic powder was quantified using HS-GC with the optimal equilibrium temperature and time conditions of 100 °C and 7 min, respectively. A new mathematical model shows that the oil absorption value can be determined from the signal of toluene. The results show that the employed method has good precision (the relative standard deviation < 3.6 %) and accuracy (R2 = 0.993). This method is simple and accurate, and can be an reliable tool for testing the oil absorption value of inorganic powder sample.


Asunto(s)
Tolueno , Polvos , Cromatografía de Gases/métodos , Temperatura , Tolueno/análisis
9.
Ultraschall Med ; 45(2): 168-175, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37402406

RESUMEN

PURPOSE: To collect validity evidence for a simulator-based obstetric ultrasound competency assessment tool (OUCAT). METHODS: 89 sonographers from three centers (XY, MC, DT), including novices (n=21), experienced trainees (n=44), and experts (n=24), participated in the competency assessment. Validity evidence of OUCAT was collected according to Standards for Educational and Psychological Testing. Content validity was ensured by reviewing guidelines and reaching expert consensus. The response process was ensured via training raters. Internal structure was explored through internal consistency, inter-rater reliability, and test-retest reliability. Relations to other variables were explored by comparing OUCAT scores of sonographers with different experience. Evidence for consequences was collected by determining the pass/fail level. RESULTS: OUCAT included 123 items, of which 117 items could effectively distinguish novices from experts (P<0.05). The internal consistency was represented by the Cronbach's α coefficient (0.978). The inter-rater reliability was high, with XY being 0.868, MC being 0.877, and DT being 0.937 (P<0.001). Test-retest reliability was 0.732 (P=0.001). The performance of experts was significantly better than experienced trainees, and the performance of experienced trainees was significantly better than novices (70.3±10.7 vs. 39.8±15.0 vs. 20.5±10.6, P<0.001). The pass/fail level determined by contrast group method was 45 points. The passing rate of novices, experienced trainees and experts was 0% (0/21), 31.8% (14/44), and 100% (24/24), respectively. CONCLUSION: Simulator-based OUCAT exhibits good reliability and validity in assessing obstetric ultrasound skills.


Asunto(s)
Competencia Clínica , Ultrasonografía Prenatal , Femenino , Embarazo , Humanos , Reproducibilidad de los Resultados , Ultrasonografía , Evaluación Educacional/métodos
11.
J Matern Fetal Neonatal Med ; 36(2): 2285239, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38010356

RESUMEN

Objective: To evaluate the changes in cardiac morphology of fetuses with congenital heart disease (CHD) using the fetal heart quantitative technique (fetalHQ).Methods: A total of 20 normal pregnant women (control group) and 20 pregnant women suspected of fetal CHD (case group) were included in this study. The dynamic images of the four-chamber view of the fetal heart were recorded and analyzed using fetalHQ. The global sphericity index (GSI) and 24-segment SI of the two groups were compared. The differences in the left and right ventricular 24-segment SI for each group were investigated.Results: There was no statistically significant difference in the GSI between the two groups (p > 0.05). The difference in the SI values of left ventricular segments 1-2 between the case group and control group was statistically significant (all p < 0.05), while the intergroup difference in SI of left ventricular segments 3-24 was not significant (all p > 0.05). The SI of the 24 segments of the right ventricle showed no significant intergroup difference (all p > 0.05). The difference in the left and right ventricular 24-segment SI in the case group did not reach statistical significance (all p > 0.05). In the control group, the SI values between the left and right ventricles were significantly different in segments 18-24 (all p < 0.05), and no significant difference was found in segments 1-17 (all p > 0.05). There was a statistically significant intergroup difference in the percentage of unusual left ventricular SI, determined based on Z-score (p < 0.05), and the percentage of outliers for the right ventricle between the two groups showed no significant difference (p > 0.05).Conclusion: The fetalHQ is regarded as a straightforward and reliable approach for assessing the cardiac GSI and 24-segment SI of left and right ventricles in fetuses diagnosed with CHD. While CHD may not significantly impact the overall shape of the fetal heart or the geometric shape of the right ventricle, in this study, a notable increase in SI values for the left ventricular 1-2 segments was observed, indicating a more flattened ventricular chamber. Additionally, the morphological distinctions between the left and right ventricles in fetuses with CHD are no longer discernible.


Asunto(s)
Enfermedades Fetales , Cardiopatías Congénitas , Femenino , Humanos , Embarazo , Ultrasonografía Prenatal/métodos , Corazón Fetal/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/anomalías
12.
BMC Pregnancy Childbirth ; 23(1): 723, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821915

RESUMEN

BACKGROUND: Whether intrauterine transmission of COVID-19 occurs remains uncertain, and it remains unclear whether the disease affects fetuses. We present a case of intrauterine transmission of SARS-CoV-2 infection and the prenatal ultrasonographic findings of the fetus in a pregnant woman with mild COVID-19. CASE PRESENTATION: A 30-year-old woman was admitted to our hospital for ultrasound examination in January 2023 at 26+ 3 weeks' gestation. Twenty-one days prior, her COVID-19 nucleic acid test was positive, and she had mild symptoms, including fever (38.3 °C), headache, chills, ankle pain and cough. After receiving symptomatic treatment, she fully recovered. Prenatal ultrasound revealed that the placenta was diffusely distributed with punctate echogenic foci, hepatomegaly, and the volume of bilateral lungs decreased significantly, with enhanced echo. In addition, we found that the surface of the fetal brain demonstrated widened gyri with a flattened surface. The prenatal MRI confirmed these fetal abnormalities. Amniotic fluid was tested for SARS-CoV-2, and the sample tested was positive for the virus. After careful consideration, the pregnant woman decided to terminate the pregnancy. CONCLUSION: The intrauterine transmission of COVID-19 is certain. Moreover, the intrauterine transmission of COVID-19 may cause abnormalities in various organs of the fetus.


Asunto(s)
COVID-19 , Complicaciones Infecciosas del Embarazo , Femenino , Embarazo , Humanos , Adulto , SARS-CoV-2 , Mujeres Embarazadas , Complicaciones Infecciosas del Embarazo/diagnóstico , Feto , Placenta/diagnóstico por imagen , Líquido Amniótico , Transmisión Vertical de Enfermedad Infecciosa , Ultrasonografía Prenatal
13.
J Adv Res ; 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37709197

RESUMEN

INTRODUCTION: Proprotein convertase subtilisin/kexin type 9 (PCSK9) is implicated in the pathogenesis and progression of autoimmune disease. Patients with rheumatoid arthritis (RA) are at high risk of developing atrial fibrillation (AF), while whether PCSK9 is involved in the onset of AF among RA patients remains unclear. OBJECTIVES: To explore the role of PCSK9 in the occurrence of AF in RA patients and decipher the underlying mechanism. METHODS: We established a rat model of collagen-induced arthritis (CIA) by immunization with type II collagen in Freund's incomplete adjuvant. Atrial electrophysiological test was used to evaluate AF susceptibility. We performed a clinical study to examine the correlation between PCSK9 level and AF, which recruited healthy control, RA patients and RA patients complicated with AF. Evolocumab (a monoclonal antibody of PCSK9) is administered via intraperitoneal injection in CIA rats to assess the role of PCSK9 in RA-related AF. LPS-RS (LPS inhibitor), clodronate liposomes (depletion of macrophages), and cell co-culture model were used to dissect the mechanism underlying PCSK9 promotes AF. RESULTS: AF inducibility and duration were higher in CIA rats, accompanied by elevated plasma and atrial PCSK9. Interestingly, compared with healthy control subjects, patients with RA showed an increase in PCSK9, and the PCSK9 is much higher in RA patients complicated with AF. The level of PCSK9 was independently associated with AF risk in RA patients. In the in vivo experiment, evolocumab reduced AF susceptibility, and ameliorated atrial structural remodeling of CIA rats. Mechanistically, augmented LPS in CIA rats led to an increase in PCSK9, which exacerbated fibrosis of cardiac fibroblasts and apoptosis of cardiac myocytes by enhancement of M1 macrophages polarization and inflammation, thereby contributing to AF. CONCLUSION: This study suggests that elevated PCSK9 causes atrial structural remodeling by enhancement of M1 macrophages polarization in atria, and evolocumab can effectively protects CIA rats from AF.

14.
J Chromatogr A ; 1710: 464404, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37769425

RESUMEN

This paper presents a multiple headspace extraction (MHE) analysis technique to determine the water vapor transmission rate of cellulose-based papers. The water vapor passing through the sample in a closed headspace vial is determined by MHE-gas chromatography. The results show that the employed method offers good precision (the relative standard deviation < 3.49 %) and good accuracy. The method is rapid and accurate, and is promising for the determination of the water vapor transmission rate of cellulose-based papers in future studies.

15.
Nanomaterials (Basel) ; 13(3)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36770565

RESUMEN

Accurate monitoring of blood glucose levels is crucial for the diagnosis of diabetes patients. In this paper, we proposed a simple "mixed-catalyzer layer" modified silicon nanowire field-effect transistor biosensor that enabled direct detection of glucose with low-charge in high ionic strength solutions. A stable screening system was established to overcome Debye screening effect by forming a porous biopolymer layer with polyethylene glycol (PEG) modified on the surface of SiNW. The experimental results show that when the optimal ratio (APTMS:silane-PEG = 2:1) modified the surface of silicon nanowires, glucose oxidase can detect glucose in the concentration range of 10 nM to 10 mM. The sensitivity of the biosensor is calculated to be 0.47 µAcm-2mM-1, its fast response time not exceeding 8 s, and the detection limit is up to 10 nM. This glucose sensor has the advantages of high sensitivity, strong specificity and fast real-time response. Therefore, it has a potential clinical application prospect in disease diagnosis.

16.
Org Lett ; 25(4): 688-693, 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36662026

RESUMEN

A carbene-catalyzed reaction to synthesize a chiral quinazolinone with a new activation mode of an "aniline-like" N-H moiety is disclosed. Addition of the nitrogen atom of diphenyl o-aminobenzaldehydes via NHC activation to imines leads to chiral quinazolinones with high yields and optical purities. The acidity of the N-H moiety was extremely increased through the formation of an acyl azolium intermediate, which was investigated by DFT calculations. Moreover, the chiral quinazolinones were found to have high fluorescence quantum efficiency.

17.
J Sep Sci ; 46(1): e2200656, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36285382

RESUMEN

This paper reports a method for determining the carbonate content in barite ore using headspace gas chromatography. Based on the acidification reaction, the carbonate in the barite ore was converted to CO2 in a closed headspace vial. When the carbonate content was significant, the pressure caused changes in the CO2 and O2 signals and affected the measurement accuracy. It was found that carbonate content is proportional to the intensity ratio of the CO2 to O2 signals. Thus, the carbonate content in barite ore can be measured indirectly using a theoretical model. The results showed that the carbonate in 3 g of barite ore sample with a particle size of 74 µm could react completely with a hydrochloric acid solution (2 mol/L) at 65°C for 5 min. The method described herein had good precision (relative standard deviation < 4.14%) and accuracy (relative differences < 6.12%). Further, the limit of quantification was 0.07 mol/L. Owing to its simplicity and speed, this method can be used for the batch determination of carbonate content in barite ore.


Asunto(s)
Sulfato de Bario , Dióxido de Carbono , Carbonatos , Ácidos , Cromatografía de Gases/métodos
18.
BMC Bioinformatics ; 23(1): 493, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36401161

RESUMEN

BACKGROUND: Accurate annotation of protein function is the key to understanding life at the molecular level and has great implications for biomedicine and pharmaceuticals. The rapid developments of high-throughput technologies have generated huge amounts of protein-protein interaction (PPI) data, which prompts the emergence of computational methods to determine protein function. Plagued by errors and noises hidden in PPI data, these computational methods have undertaken to focus on the prediction of functions by integrating the topology of protein interaction networks and multi-source biological data. Despite effective improvement of these computational methods, it is still challenging to build a suitable network model for integrating multiplex biological data. RESULTS: In this paper, we constructed a heterogeneous biological network by initially integrating original protein interaction networks, protein-domain association data and protein complexes. To prove the effectiveness of the heterogeneous biological network, we applied the propagation algorithm on this network, and proposed a novel iterative model, named Propagate on Heterogeneous Biological Networks (PHN) to score and rank functions in descending order from all functional partners, Finally, we picked out top L of these predicted functions as candidates to annotate the target protein. Our comprehensive experimental results demonstrated that PHN outperformed seven other competing approaches using cross-validation. Experimental results indicated that PHN performs significantly better than competing methods and improves the Area Under the Receiver-Operating Curve (AUROC) in Biological Process (BP), Molecular Function (MF) and Cellular Components (CC) by no less than 33%, 15% and 28%, respectively. CONCLUSIONS: We demonstrated that integrating multi-source data into a heterogeneous biological network can preserve the complex relationship among multiplex biological data and improve the prediction accuracy of protein function by getting rid of the constraints of errors in PPI networks effectively. PHN, our proposed method, is effective for protein function prediction.


Asunto(s)
Algoritmos , Mapeo de Interacción de Proteínas , Mapeo de Interacción de Proteínas/métodos , Anotación de Secuencia Molecular , Mapas de Interacción de Proteínas , Proteínas/metabolismo
19.
Pharm Biol ; 60(1): 1762-1770, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36086802

RESUMEN

CONTEXT: (-)-Epicatechin (EPI) is a crucial substance involved in the protective effects of flavanol-rich foods. Previous studies have indicated EPI has a cardioprotective effect, but the molecular mechanisms in inhibition of cardiac fibrosis are unclear. OBJECTIVE: We evaluated the effect of EPI in preventing cardiac fibrosis and the underlying molecular mechanism related to the SIRT1-SUMO1/AKT/GSK3ß pathway. MATERIALS AND METHODS: Cardiac fibrosis mice model was established with transaortic constriction (TAC). Male C57BL/6 mice were randomly separated into 4 groups. Mice received 1 mg/kg/day of EPI or vehicle orally for 4 weeks. The acutely isolated cardiac fibroblasts were induced to myofibroblasts with 1 µM angiotensin II (Ang II). The cardiac function was measured with the ultrasonic instrument. Histological analysis of mice's hearts was determined with H&E or Masson method. The protein level of fibrosis markers, SUMOylation of SIRT1, and AKT/GSK3ß pathway were quantified by immunofluorescence and western blot. RESULTS: EPI treatment (1 mg/kg/day) could reverse the TAC-induced decline in LVEF (TAC, 61.28% ± 1.33% vs. TAC + EPI, 74.00% ± 1.64%), LVFS (TAC, 28.16% ± 0.89% vs. TAC + EPI, 37.18% ± 1.29%). Meantime, we found that 10 µM EPI blocks Ang II-induced transformation of cardiac fibroblasts into myofibroblasts. The underlying mechanism of EPI-inhibited myofibroblasts transformation involves activation of SUMOylation of SIRT1 through SP1. Furthermore, SUMOylation of SIRT1 inhibited Ang II-induced fibrogenic effect via the AKT/GSK3ß pathway. CONCLUSION: EPI plays a protective effect on cardiac fibrosis by regulating the SUMO1-dependent modulation of SIRT1, which provides a theoretical basis for use in clinical therapies.


Asunto(s)
Catequina , Miofibroblastos , Angiotensina II/toxicidad , Animales , Catequina/farmacología , Fibroblastos/patología , Fibrosis , Glucógeno Sintasa Quinasa 3 beta , Masculino , Ratones , Ratones Endogámicos C57BL , Miofibroblastos/metabolismo , Miofibroblastos/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Sirtuina 1/metabolismo , Ubiquitina
20.
Eur J Pediatr ; 181(10): 3645-3654, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35978254

RESUMEN

To establish the cross-sectional reference values of cerebral ventricular size for the Chinese newborns by the most correlated explanatory variables. The anterior horn width (AHW), thalamo-occipital distance (TOD), and ventricular index (VI) were collected prospectively from 1- to 7-day neonates without potential neurological problems. All neonates were delivered or treated at the Hunan Provincial Maternal and Child Health Care Hospital or Second Xiangya Hospital of Central South University between February and August 2021. The most correlated explanatory variables were identified with the max-min normalization and multiple regression. The reference values were then established based on the above variables. Additionally, intraclass correlation coefficients (ICC) were applied to evaluate the reliability of the overall data collection process. This prospective study consisted of 1848 neonates. The AHW was most highly correlated with GA; the TOD and VI were most strongly correlated with birth weight. All the foregoing correlations were positive ones. Heteroscedasticity and influential points existed in both TOD and VI. The ICCAHW was the largest to a specific rater or between raters, the ICCTOD the second largest, and the ICCVI the smallest. CONCLUSIONS: We recommend using the GA-based AHW reference values and birth weight-based TOD and VI ones. We also present a comparison of GA-based upper limits from all available reference intervals. Moreover, we determine that measurement errors are the primary cause of influential points and heteroscedasticity in TOD and VI studies and infer that the studies of TOD and VI are vulnerable to them. WHAT IS KNOWN: • Reference values of infantile cerebral ventricles are vital in diagnosing and treating cerebral ventricular dilatation. • Precursors established gestational age-based reference values subjectively. WHAT IS NEW: • We set cross-sectional reference values based on the most correlated variables for Chinese neonates and compared all available gestational age-based upper limits. • Influential points and heteroscedasticity mainly caused by measurement errors are common in TOD and VI studies.


Asunto(s)
Ventrículos Cerebrales , Peso al Nacer , Niño , China , Estudios Transversales , Femenino , Edad Gestacional , Humanos , Recién Nacido , Embarazo , Estudios Prospectivos , Valores de Referencia , Reproducibilidad de los Resultados
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