Macrophages-derived exo-miR-4449 induced by Cryptococcus affects HUVEC permeability and promotes pyroptosis in BEAS-2B via the HIC1 pathway.

Macrophages have recently been discovered to assume a significant role in the progression of cryptococcosis. However, the potential involvement of macrophage-derived exosomes in the pathogenesis of cryptococcosis remains uncertain. In this study, we investigated the changes of microRNAs in macrophage exosomes (exo-miRNAs) in cryptococcal infections and the role of markedly altered exo-miRNAs in the modulation of Human Umbilical Vein Endothelial Cells (HUVEC) permeability and ROS accumulation and pyroptosis in Human Bronchial Epithelioid Cells (BEAS-2B). Techniques such as microarray analysis and real-time quantitative PCR were used to detect different exo-miRNAs and to screen for the most highly expressed exo-miRNAs. Then its mimics were transfected into HUVEC to study its effect on the monolayer permeability of HUVEC. Finally, the relationship between this exo-miRNAs and the ROS accumulation and pyroptosis was verified by bioinformatics analysis. The results showed that five exo-miRNAs were overexpressed and two exo-miRNAs were reduced, among which, exo-miR-4449 was expressed at the highest level. Exo-miR-4449 could be internalized by HUVEC and enhanced its monolayer permeability. Moreover, exo-miR-4449 was found to promote ROS accumulation and pyroptosis in BEAS-2B through HIC1 pathway. Thus, exo-miR-4449 plays an important role in the pathogenesis of cryptococcosis and holds promise as a significant biomarker for treatment.

Machine learning improves early prediction of organ failure in hyperlipidemia acute pancreatitis using clinical and abdominal CT features.

BACKGROUND: This study aimed to investigate and validate machine-learning predictive models combining computed tomography and clinical data to early predict organ failure (OF) in Hyperlipidemic acute pancreatitis (HLAP). METHODS: Demographics, laboratory parameters and computed tomography imaging data of 314 patients with HLAP from the First Affiliated Hospital of Wenzhou Medical University between 2017 and 2021, were retrospectively analyzed. Sixty-five percent of patients (n = 204) were assigned to the training group and categorized as patients with and without OF. Parameters were compared by univariate analysis. Machine-learning methods including random forest (RF) were used to establish model to predict OF of HLAP. Areas under the curves (AUCs) of receiver operating characteristic were calculated. The remaining 35% patients (n = 110) were assigned to the validation group to evaluate the performance of models to predict OF. RESULTS: Ninety-three (45.59%) and fifty (45.45%) patients from the training and the validation cohort, respectively, developed OF. The RF model showed the best performance to predict OF, with the highest AUC value of 0.915. The sensitivity (0.828) and accuracy (0.814) of RF model were both the highest among the five models in the study cohort. In the validation cohort, RF model continued to show the highest AUC (0.820), accuracy (0.773) and sensitivity (0.800) to predict OF in HLAP, while the positive and negative likelihood ratios and post-test probability were 3.22, 0.267 and 72.85%, respectively. CONCLUSIONS: Machine-learning models can be used to predict OF occurrence in HLAP in our pilot study. RF model showed the best predictive performance, which may be a promising candidate for further clinical validation.

Association of food folate with asthma in US children and adolescents: a cross-sectional study.

BACKGROUND: Asthma is a chronic inflammatory disease. Currently, contradictory findings exist regarding the association between food folate and asthma. Therefore, we hypothesize a positive correlation between food folate and asthma. PURPOSE: To investigate the possible relationship between food folate intake and the development of asthma in children and adolescents in the United States. METHODS: Data from the U.S. National Health and Nutrition Examination Survey (NHANES) from 2009 to 2018 were analyzed cross-sectionally by covariate adjustment using multivariate logistic regression, restricted triple spline curves, threshold effects, and stratified analyses. RESULTS: There were 8,821 participants, of whom 1,697 (19.2%) self-reported having received a diagnosis of asthma from a physician or other health professional. After accounting for potential confounders, the adjusted odds ratios (ORs) for asthma in the second (T2, 111-178 µg/day) and third (T3, >178 µg/day) groups were 1.15 (1-1.33) and 1.23 (1.04-1.46), respectively, compared with the group with the lowest food folate intake (T1, <111 µg/day). In addition, the association between food folate intake and asthma showed an inverse L-shaped curve (non-linear relationship, p = 0.003), and stratified analysis further validated the robustness of the results. The OR of asthma in subjects with food folate intake less than 263.9 µg/day was 1.002 (1.001-1.004). CONCLUSION: In children and adolescents in the United States, there is a non-linear association (inverted "L" shape) between food folate intake and asthma, with an inflection point at 263.9 micrograms per day.

The yield of SNP microarray analysis for fetal ultrasound cardiac abnormalities.

BACKGROUND: Chromosomal microarray analysis (CMA) has emerged as a critical instrument in prenatal diagnostic procedures, notably in assessing congenital heart diseases (CHD). Nonetheless, current research focuses solely on CHD, overlooking the necessity for thorough comparative investigations encompassing fetuses with varied structural abnormalities or those without apparent structural anomalies. OBJECTIVE: This study sought to assess the relation of single nucleotide polymorphism-based chromosomal microarray analysis (SNP-based CMA) in identifying the underlying causes of fetal cardiac ultrasound abnormalities. METHODS: A total of 2092 pregnant women who underwent prenatal diagnosis from 2017 to 2022 were included in the study and divided into four groups based on the presence of ultrasound structural abnormalities and the specific type of abnormality. The results of the SNP-Array test conducted on amniotic fluid samples from these groups were analyzed. RESULTS: Findings from the study revealed that the non-isolated CHD group exhibited the highest incidence of aneuploidy, overall chromosomal abnormalities, and trisomy 18, demonstrating statistically significant differences from the other groups (p < 0.001). Regarding the distribution frequency of copy number variation (CNV) segment size, no statistically significant distinctions were observed between the isolated CHD group and the non-isolated CHD group (p > 0.05). The occurrence rates of 22q11.2 and 15q11.2 were also not statistically different between the isolated CHD group and the non-isolated congenital heart defect group (p > 0.05). CONCLUSION: SNP-based CMA enhances the capacity to detect abnormal CNVs in CHD fetuses, offering valuable insights for diagnosing chromosomal etiology and facilitating genetic counseling. This research contributes to the broader understanding of the utility of SNP-based CMA in the context of fetal cardiac ultrasound abnormalities.

Novel anthropometric indicators of visceral obesity predict the severity of hyperlipidemic acute pancreatitis.

BACKGROUND: Obesity substantially contributes to the onset of acute pancreatitis (AP) and influences its progression to severe AP. Although body mass index (BMI) is a widely used anthropometric parameter, it fails to delineate the distribution pattern of adipose tissue. To circumvent this shortcoming, the predictive efficacies of novel anthropometric indicators of visceral obesity, such as lipid accumulation products (LAP), cardiometabolic index (CMI), body roundness index (BRI), visceral adiposity index (VAI), A Body Shape Index (ABSI), and Chinese visceral adiposity index (CVAI) were examined to assess the severity of AP. METHOD: The body parameters and laboratory indices of 283 patients with hyperlipidemic acute pancreatitis (HLAP) were retrospectively analysed, and the six novel anthropometric indicators of visceral obesity were calculated. The severity of HLAP was determined using the revised Atlanta classification. The correlation between the six indicators and HLAP severity was evaluated, and the predictive efficacy of the indicators was assessed using area under the curve (AUC). The differences in diagnostic values of the six indicators were also compared using the DeLong test. RESULTS: Patients with moderate to severe AP had higher VAI, CMI, and LAP than patients with mild AP (all P < 0.001). The highest AUC in predicting HLAP severity was observed for VAI, with a value of 0.733 and 95% confidence interval of 0.678-0.784. CONCLUSIONS: This study demonstrated significant correlations between HLAP severity and VAI, CMI, and LAP indicators. These indicators, particularly VAI, which displayed the highest predictive power, were instrumental in forecasting and evaluating the severity of HLAP.

PRECEDE-PROCEED Model Nursing Intervention in Health Education for Parents of Obese Children.

Objective: To study the intervention effects of the health education and health promotion (PRECEDE-PROCEED) model on the health behaviors and quality of life of obese children and their parents. Methods: 524 patients who attended our pediatric obesity clinic from January to December 2021 were selected and divided into two groups: the control group (n = 262) and the test group (n = 262). The control group was guided by conventional weight reduction instruction, while the test group implemented the PRECEDE-PROCEED model. Based on this model, interventions were developed following the 9 links of the model, with tendency factors, contributing factors, and reinforcing factors as the core and 6 aspects of health behaviors were focused upon, and were followed up for 12 months. A home-made questionnaire scale was used to assess the subjects at their initial visit and one year after the intervention. Results: After the intervention, the awareness rate of obesity-related knowledge, support rate of attitude toward improving childhood obesity, awareness rate of disease harm caused by obesity, and formation rate of controlling childhood obesity behavior had significantly improved among the parents of the test group compared to the control group, with significant differences between the two groups (P < .05). Conclusion: The PRECEDE-PROCEED model can transform the way parents of obese children apply health education at home, improving health behaviors and quality of life.

Is HER2 ultra-low breast cancer different from HER2 null or HER2 low breast cancer? A study of 1363 patients.

OBJECTIVE: This study aims to analyze whether there are any differences in clinicopathological features and prognosis between HER2 ultra-low, HER2-null, and HER2-low expression in Chinese breast cancer (BC) patients. METHODS: The clinicopathological data of 1363 HER2-negative BC patients were retrospectively collected (from January 2018 to December 2019). HER2 status was further classified into HER2-null, HER2 ultra-low, and HER2-low. HER2-null expression is defined as infiltrating cancer cells completely free of staining. HER2 ultra-low expression is defined as ≤10% of infiltrating cancer cells showing incomplete and faint/weak membrane staining. HER2-low expression is defined as HER2 immunohistochemistry (IHC) 1+ or 2+ with negative in situ hybridization (ISH) assay. RESULTS: Of 1363 patients, there were 86 (6.3%) HER2-null patients, 395 (29.0%) HER2 ultra-low patients, and 882 (64.7%) HER2-low patients. HER2 ultra-low patients were different from HER2-low patients in terms of N stage, hormone receptor (HR) status, Ki-67 expression, and type of surgery. There were also significant differences in histologic type and postoperative endocrine therapy between HER2 ultra-low and HER2-null patients. HR+ (81.0%) tumors was more common than HR- (19.0%) in HER2 ultra-low patients. In addition, there was a significant difference in HR status between HER2 ultra-low and HER2-low patients (P = 0.001). The survival analysis showed that HER2 status had no effect on disease-free survival (DFS) in HER2-negative patients (all P > 0.05). However, regardless of HER2 status, HR+ patients had better DFS than HR- patients (P = 0.003). Cox multivariate analysis revealed that age (HR [95% CI] = 0.950 [0.928, 0.972], P < 0.001), HR status (HR [95% CI] = 3.342 [1.658, 6.736], P = 0.001), and postoperative endocrine therapy (HR [95% CI] = 0.048 [0.048, 0.023], P < 0.001) were important influencing factors of DFS in HER2-negative BC patients. CONCLUSION: HER2 ultra-low BC patients demonstrated distinct clinicopathological features from HER2-null and HER2-low tumors; while, HER2 status (null, ultra-low, or low) had no prognostic value in these HER2-negative BC population. Consistent with the published literature, HR status was an independent prognostic factor for DFS in HER2-negative BC patients.

How To Be a Successful Monopartite Begomovirus in a Bipartite-Dominated World: Emergence and Spread of Tomato Mottle Leaf Curl Virus in Brazil.

Begomoviruses are members of the family Geminiviridae, a large and diverse group of plant viruses characterized by a small circular single-stranded DNA genome encapsidated in twinned quasi-icosahedral virions. Cultivated tomato (Solanum lycopersicum L.) is particularly susceptible and is infected by >100 bipartite and monopartite begomoviruses worldwide. In Brazil, 25 tomato-infecting begomoviruses have been described, most of which are bipartite. Tomato mottle leaf curl virus (ToMoLCV) is one of the most important of these and was first described in the late 1990s but has not been fully characterized. Here, we show that ToMoLCV is a monopartite begomovirus with a genomic DNA similar in size and genome organization to those of DNA-A components of New World (NW) begomoviruses. Tomato plants agroinoculated with the cloned ToMoLCV genomic DNA developed typical tomato mottle leaf curl disease symptoms, thereby fulfilling Koch's postulates and confirming the monopartite nature of the ToMoLCV genome. We further show that ToMoLCV is transmitted by whiteflies, but not mechanically. Phylogenetic analyses placed ToMoLCV in a distinct and strongly supported clade with other begomoviruses from northeastern Brazil, designated the ToMoLCV lineage. Genetic analyses of the complete sequences of 87 ToMoLCV isolates revealed substantial genetic diversity, including five strain groups and seven subpopulations, consistent with a long evolutionary history. Phylogeographic models generated with partial or complete sequences predicted that the ToMoLCV emerged in northeastern Brazil >700 years ago, diversifying locally and then spreading widely in the country. Thus, ToMoLCV emerged well before the introduction of MEAM1 whiteflies, suggesting that the evolution of NW monopartite begomoviruses was facilitated by local whitefly populations and the highly susceptible tomato host. IMPORTANCE Worldwide, diseases of tomato caused by whitefly-transmitted geminiviruses (begomoviruses) cause substantial economic losses and a reliance on insecticides for management. Here, we describe the molecular and biological properties of tomato mottle leaf curl virus (ToMoLCV) from Brazil and establish that it is a NW monopartite begomovirus indigenous to northeastern Brazil. This answered a long-standing question regarding the genome of this virus, and it is part of an emerging group of these viruses in Latin America. This appears to be driven by widespread planting of the highly susceptible tomato and by local and exotic whiteflies. Our extensive phylogenetic studies placed ToMoLCV in a distinct strongly supported clade with other begomoviruses from northeastern Brazil and revealed new insights into the origin of Brazilian begomoviruses. The novel phylogeographic analysis indicated that ToMoLCV has had a long evolutionary history, emerging in northeastern Brazil >700 years ago. Finally, the tools used here (agroinoculation system and ToMoLCV-specific PCR test) and information on the biology of the virus (host range and whitefly transmission) will be useful in developing and implementing integrated pest management (IPM) programs targeting ToMoLCV.

The association between n-3 polyunsaturated fatty acid intakes and asthma in US children and adolescents: A cross-sectional study from NHANES.

BACKGROUND: Asthma is an inflammatory disease. The potential of n-3 polyunsaturated fatty acids (PUFAs) to alleviate asthma symptoms through their anti-inflammatory effects and immune modulation has been explored. However, the precise role of dietary n-3 PUFAs in childhood and adolescent asthma remains unclear. OBJECTIVE: This study aimed to evaluate the association between dietary n-3 PUFAs intake and asthma in children and adolescents in the United States. METHODS: We conducted a cross-sectional analysis of 8543 children and adolescents from the National Health and Nutrition Examination Survey (NHANES) between 2013 and 2020 by adjusting for covariates and using multivariate logistic regression, restricted cubic spline, threshold effects, and subgroup analyses. RESULTS: Among 8354 participants, 1456 (16.5%) self-reported diagnosis of asthma by a healthcare provider. After adjusting for potential confounding factors, compared with individuals in the lowest n-3 PUFA consumption group (T1, <26.07 mg/kg/day), the adjusted odds ratio (OR) for asthma was 0.71 (95% CI: 0.6-0.84, p < .001) in the second group (T2, 26.07-48.93 mg/kg/day) and 0.58 (95% CI: 0.47-0.73, p < .001) in the third group (T3, >48.93 mg/kg/day). Furthermore, a nonlinear (L-shaped) relationship was observed between n-3 PUFA intake and asthma (p = .009), with subgroup and sensitivity analyses confirming the stability of the results. In the threshold analysis, a critical turning point was observed at approximately 59.0 mg/kg/day (OR = 0.984, 95% CI: 0.977-0.991, p < .001). CONCLUSION: Dietary intake of n-3 PUFAs exhibited an L-shaped relationship with asthma in children and adolescents in the United States, with a critical turning point observed at approximately 59.0 mg/kg/day.

The impact of metabolic dysfunction-associated fatty liver disease on the prognosis of patients with hepatocellular carcinoma after radical resection.

BACKGROUND: Metabolic dysfunction-associated fatty liver disease (MAFLD) is recently proposed an entity by a group of international experts. However, the impact of MAFLD on the prognosis of patients with hepatocellular carcinoma (HCC) is not clear. The aim of this study was to explore the influence of MAFLD for the prognosis of HCC after radical resection. METHODS: HCC patients who received radical resection were enrolled. The recurrence-free survival (RFS) and overall survival (OS) were compared between MAFLD and non-MAFLD. RESULTS: A total of 576 HCC patients were included, and among them 114 (19.8%) met the diagnostic criteria of MAFLD. The median RFS was 34.0 months in the MAFLD group and 19.0 months in the non-MAFLD group. The 1-, 3-, and 5-year RFS rates were 64.9%, 49.1% and 36.1% in the MAFLD group, which were higher than those of the non-MAFLD group (59.4%, 35.3% and 26.5%, respectively, P = 0.01). The mean OS was 57.0 months in the MAFLD group and 52.2 months in the non-MAFLD group. There was no statistical difference in OS rate between the MAFLD group and non-MAFLD group. Similar results were found in HBV-related HCC patients in the subgroup analysis. Univariate analysis revealed that MAFLD was a protective factor for RFS in HCC patients after radical resection (P < 0.05), and there was no association between MAFLD and OS rate (P > 0.05). Multivariate analysis demonstrated that MAFLD was not an independent protective factor for HCC patients with radical resection. CONCLUSIONS: MAFLD improves RFS rate in HCC patients with radical resection, but is not an independent protective factor and not associated with OS rate.

TBUnet: A Pure Convolutional U-Net Capable of Multifaceted Feature Extraction for Medical Image Segmentation.

Many current medical image segmentation methods utilize convolutional neural networks (CNNs), with some extended U-Net-based networks relying on deep feature representations to achieve satisfactory results. However, due to the limited receptive fields of convolutional architectures, they are unable to explicitly model the varying range dependencies present in medical images. Recently, advancements in large kernel convolution have allowed for the extraction of a wider range of low frequency information, making this task more achievable. In this paper, we propose TBUnet for solving the problem of difficult to accurately segment lesions with heterogeneous structures and fuzzy borders, such as melanoma, colon polyps and breast cancer. The TBUnet is a pure convolutional network with three branches for extracting high frequency information, low frequency information, and boundary information, respectively. It is capable of extracting features in various areas. To fuse the feature maps from the three branches, TBUnet presents the FL (fusion layer) module, which is based on threshold and logical operation. We design the FE (feature enhancement) module on the skip-connection to emphasize the fine-grained features. In addition, our method varies the number of input channels in different branches at each stage of the network, so that the relationship between low and high frequency features can be learned. TBUnet yields 91.08 DSC on ISIC-2018 for melanoma segmentation, and achieves better performance than state-of-the-art medical image segmentation methods. Furthermore, experimental results with 82.48 DSC and 89.04 DSC obtained on the BUSI dataset and the Kvasir-SEG dataset show that TBUnet outperforms the advanced segmentation methods. Experiments demonstrate that TBUnet has excellent segmentation performance and generalisation capability.

Research Progress on Microbial Community Succession in the Postmortem Interval Estimation.

The postmortem interval (PMI) estimation is a key and difficult point in the practice of forensic medicine, and forensic scientists at home and abroad have been searching for objective, quantifiable and accurate methods of PMI estimation. With the development and combination of high-throughput sequencing technology and artificial intelligence technology, the establishment of PMI model based on the succession of the microbial community on corpses has become a research focus in the field of forensic medicine. This paper reviews the technical methods, research applications and influencing factors of microbial community in PMI estimation explored by using high-throughput sequencing technology, to provide a reference for the related research on the use of microbial community to estimate PMI.

Theoretical study on ferroelectric nitrides with super-wurtzite structures for solar energy conversion applications.

Polarized structured nitride semiconductors are attractive due to their unique and environment-friendly electronic properties. The stability, ferroelectricity and photocatalytic and photovoltaic properties of super-wurtzite Mg2XN3 (X = Bi, Mo, Nb, Sb, Ta, Tc and W) were determined based on first principles calculations in this study. The calculated results indicate that Mg2XN3 (X = Sb, Ta, Bi and Nb) are stable polar nitrides by phonon frequencies, elastic coefficients and ferroelectric analysis. Mg2XN3 (X = Sb, Ta and Nb) with large ferroelectric polarization strength could absorb ultraviolet light to promote photocatalytic water splitting for hydrogen production. Mg2BiN3 is a new excellent photovoltaic candidate due to its ideal energy band, high electron mobility, high absorption coefficient and large ferroelectric polarization strength.

BMSCs mediates endothelial cell autophagy by upregulating miR-155-5p to alleviate ventilator-induced lung injury.

In this study, we explored to detect the effects and mechanism of bone-marrow-derived mesenchymal stem cells (BMSCs) on ventilator-induced lung injury (VILI). We transplanted BMSCs in mice and then induced VILI using mechanical ventilation (MV) treatment. The pathological changes, the content of PaO2 and PaCO2 , wet/dry weight ratio (W/D) of the lung, levels of tumor necrosis factor-α and interleukin-6 in bronchoalveolar lavage fluid, and apoptosis were detected. The autophagy-associated factor p62, LC3, and Beclin-1 expression were analyzed by western blot. The quantitative polymerase chain reaction was applied to detect abnormally expressed microRNAs, including miR-155-5p. Subsequently, we overexpressed miR-155-5p in VILI mice to detect the effects of miR-155-5p on MV-induced lung injury. Then, we carried out bioinformatics analysis to verify the BMSCs-regulated miR-155-5p that target messenger RNA. It was observed that BMSCs transplantation mitigated the severity of VILI in mice. BMSCs transplantation reduced lung inflammation, strengthened the arterial oxygen partial pressure, and reduced apoptosis and the W/D of the lung. BMSCs promoted autophagy of pulmonary endothelial cells accompanied by decreased p62 and increased LC3 II/I and Beclin-1. BMSCs increased the levels of miR-155-5p in VILI mice. Overexpression of miR-155-5p alleviated lung injury in VILI mice following reduced apoptosis and increased autophagy. Finally, TAB2 was identified as a downstream target of miR-155-5p and regulated by miR-155-5p. BMSCs may protect lung tissues from MV-induced injury, inhibit lung inflammation, promote autophagy through upregulating of miR-155-5p.

Curly Top Disease of Hemp (Cannabis sativa) in California Is Caused by Mild-Type Strains of Beet curly top virus Often in Mixed Infection.

Interest in industrial hemp (Cannabis sativa) as a potential crop led to the establishment of commercial fields in a number of counties in California in 2019 and 2020. Plants in these fields developed different types of virus-like symptoms. The most prevalent type was stunted and bushy plants with distorted, upcurled, and yellowed leaves, which were similar to those associated with curly top disease (CTD) caused by the beet curly top virus (BCTV). This beet leafhopper-vectored virus is endemic in California and can cause economic losses to processing tomato production. Using a multiplex PCR test, BCTV infection was detected in 89% of hemp samples with CTD-like symptoms from Fresno, San Bernardino, and Ventura counties. Other symptom types had low incidence of BCTV infection and were associated with other factors. Hemp plants in California were infected only with the mild-type strains, BCTV-CO and BCTV-Wor, and often in mixed infection (43% of samples). Finally, using an infectious clone of a BCTV-CO isolate from hemp, we demonstrated that agroinoculated hemp plants developed these CTD-like symptoms, thereby fulfilling Koch's postulates for the disease.

Fast Assembly of Metal Organic Framework UiO-66 in Acid-Base Tunable Deep Eutectic Solvent for the Acetalization of Benzaldehyde and Methanol.

Zirconium-based metal-organic frameworks (MOFs) have attracted extensive attention owing to their robust stability and facile functionalization. However, they are generally prepared in common volatile solvents within a long reaction time. Here, we introduced environmentally friendly, cheap, and acid-based tunable deep eutectic solvents (DESs) formed from 2-methyl imidazole (MIm) and p-toluenesulfonic acid (PTSA) which significantly accelerated the assembly of zirconium-based MOF (UiO-66) without any aggressive additives. PTSA in acidic DES and ZrOCl2 preliminarily formed Zr(IV) oxo organic acid framework, whereas basic DES completely dissolved the ligand of UiO-66. The strong hydrogen bond effect of PTSA and MIm efficiently accelerated the linker exchange between zirconium oxo organic coordination in acidic DES and benzenedicarboxylate linker in weak basic DES within a reaction time of 2 h at 50 °C. Thus, UiO-66 was quickly assembled with small particle sizes and used as an excellent catalyst for the acetalization of benzaldehyde and methanol. Therefore, the developed synthesis approach provides a new green strategy to quickly prepare and design various structures of metal-based compounds under mild reaction conditions.

Effects of Digestive Temperature and Time on Diatom Test.

OBJECTIVES: To study the effects of temperature and time for diatoms digestion and find out suitable digestive temperature and time. METHODS: Eighty pieces of liver tissues were collected, each piece of tissue was 2 g, and 2 mL Pearl River water was added to each piece of tissue. The digestion temperature was set at 100 ℃, 120 ℃, 140 ℃, 160 ℃, 180 ℃ and the digestion time was set at 40, 50, 60, 70, 80 min. The liver tissue and water mixture were divided into 8 portions in each group. All the samples were tested by microwave digestive - vacuum filtration - automated scanning electron microscopy method. The quantity of diatom recovered and the quality of residue on the membrane were recorded. RESULTS: When the digestion time was set to 60 min, there were statistically significant differences in the number of diatoms recovered at different temperatures (P<0.05). The maximum number of diatoms recovered was (28 797.50±6 009.67) at 140 ℃, and the minimum residue was (0.60±0.28) mg at 180 ℃. When the digestion temperature was set at 140 ℃, there were statistically significant differences in the number of diatoms recovered at different digestion times (P<0.05). The number of diatoms recovered was the highest at 40 min, it was up to (20 650.88±1 950.29), and the residue quality of each group had no statistical significance among different digestion time groups(P>0.05). CONCLUSIONS: The effect of diatom digestion is related to temperature and time. When the digestion temperature was 140 ℃ and the digestion time was 40, 50 and 60 min, it is favorable for diatom test.

Correction: A kinetics study on hydrogen abstraction reactions of cyclopentane by hydrogen, methyl, and ethyl radicals.

Correction for 'A kinetics study on hydrogen abstraction reactions of cyclopentane by hydrogen, methyl, and ethyl radicals' by Wenqi Chen et al., Phys. Chem. Chem. Phys., 2021, 23, 7333-7342, DOI: 10.1039/D1CP00386K.

A kinetics study on hydrogen abstraction reactions of cyclopentane by hydrogen, methyl, and ethyl radicals.

Hydrogen abstraction reactions of (cyclo)alkanes by radicals play a fundamental role in both combustion and atmospheric chemistry. In this work, we select three common radicals in the pyrolysis of hydrocarbon fuels: hydrogen radical (H[combining dot above]), methyl radical (CH3), and ethyl radical (CH2CH3) to investigate the kinetics of their hydrogen abstraction reactions with cyclopentane. The rate constants over a broad temperature range of 150-3000 K are calculated by using the multi-structural variational transition state theory in the small-curvature tunneling approximation (MS-CVT/SCT), by which the multi-structural torsional (MS-T) anharmonicity of partition functions, variational effects, and corner-cutting tunneling are all included in dynamics calculations. We stress the particular importance of considering the MS-T anharmonicity in the rate constant calculation for the reaction with the ethyl radical compared to those with hydrogen and methyl radicals. The MS-T anharmonicity significantly accelerates the reaction with the ethyl radical in the whole temperature range, and in particular, it increases the rate constant by a factor of >-9 at 1000 K. We also found that the tunneling effect drastically increases the rate constants at low-temperatures by up to 3-5 orders of magnitudes. The calculated reaction rate constants have an order of .

SIRT6 inhibits cholesterol crystal-induced vascular endothelial dysfunction via Nrf2 activation.

Sirtuin 6 (SIRT6), a nicotinamide adenine dinucleotide-dependent deacetylase, participates in various age-related disorders, such as dyslipidemia and cardiovascular diseases. Recent studies have revealed that minute cholesterol crystals (CCs), which are generated after excess free cholesterol accumulation, form not only in mature atherosclerotic plaques but also extremely early in atherosclerosis. Since endothelial dysfunction is an early feature of atherogenesis, this study was designed to investigate the role of SIRT6 in minute CC-induced endothelial dysfunction and the related mechanism. We found that minute CCs could be endocytosed by endothelial cells (ECs), which then decreased nitric oxide (NO) levels and endothelial nitric oxide synthase (eNOS) activity and expression, upregulated the expression of adhesion molecules and enhanced monocyte adhesion to ECs. In addition, minute CCs significantly suppressed SIRT6 expression in ECs. Moreover, the overexpression of SIRT6 could mitigate minute CC-induced endothelial dysfunction. In addition, the expression of Nuclear factor erythroid2-related factor2 (Nrf2) was suppressed after minute CC treatment, whereas SIRT6 overexpression reversed this decrease in Nrf2 expression. More importantly, Nrf2 activation also notably attenuated minute CC-induced endothelial dysfunction. In vivo experiments further indicated that endothelium-specific SIRT6 depletion impaired vascular endothelial function and suppressed Nrf2 expression in hyperlipidemic mice. Taken together, these results indicate that SIRT6 rescues minute CC-induced endothelial dysfunction partly via Nrf2 activation.