Correction of preferred orientation-induced distortion in cryo-electron microscopy maps.

Reconstruction maps of cryo-electron microscopy (cryo-EM) exhibit distortion when the cryo-EM dataset is incomplete, usually caused by unevenly distributed orientations. Prior efforts had been attempted to address this preferred orientation problem using tilt-collection strategy and modifications to grids or to air-water interfaces. However, these approaches often require time-consuming experiments, and the effect was always protein dependent. Here, we developed a procedure containing removing misaligned particles and an iterative reconstruction method based on signal-to-noise ratio of Fourier component to correct this distortion by recovering missing data using a purely computational algorithm. This procedure called signal-to-noise ratio iterative reconstruction method (SIRM) was applied on incomplete datasets of various proteins to fix distortion in cryo-EM maps and to a more isotropic resolution. In addition, SIRM provides a better reference map for further reconstruction refinements, resulting in an improved alignment, which ultimately improves map quality and benefits model building.

The role and mechanism of action of miR­92a in endothelial cell autophagy.

Although microRNAs (miRNAs/miRs) serve a significant role in the autophagy of vascular endothelial cells (ECs), the effect of miR­92a on the autophagy of ECs is currently unclear. Therefore, the present study aimed to investigate the impact of miR­92a on autophagy in ECs and the underlying molecular processes that control this biological activity. Firstly, an autophagy model of EA.hy926 cells was generated via treatment with the autophagy inducer rapamycin (rapa­EA.hy926 cells). The expression levels of miR­92a were then detected by reverse transcription­quantitative PCR, and the effect of miR­92a expression on the autophagic activity of rapa­EA.hy926 cells was studied by overexpressing or inhibiting miR­92a. The level of autophagy was evaluated by western blot analysis, immunofluorescence staining and transmission electron microscopy. Dual­luciferase reporter assays were used to confirm the interaction between miR­92a and FOXO3. The results demonstrated that the expression levels of miR­92a were decreased in the rapa­EA.hy926 cell autophagy model. Furthermore, overexpression and inhibition of miR­92a revealed that upregulation of miR­92a in these cells inhibited autophagy, whereas miR­92a knockdown promoted it. It was also confirmed that miR­92a directly bound to the 3'­untranslated region of the autophagy­related gene FOXO3 and reduced its expression. In conclusion, the present study suggested that miR­92a inhibits autophagy activity in EA.hy926 cells by targeting FOXO3.

Machine learning-based nomogram: integrating MRI radiomics and clinical indicators for prognostic assessment in acute ischemic stroke.

Background: Acute Ischemic Stroke (AIS) remains a leading cause of mortality and disability worldwide. Rapid and precise prognostication of AIS is crucial for optimizing treatment strategies and improving patient outcomes. This study explores the integration of machine learning-derived radiomics signatures from multi-parametric MRI with clinical factors to forecast AIS prognosis. Objective: To develop and validate a nomogram that combines a multi-MRI radiomics signature with clinical factors for predicting the prognosis of AIS. Methods: This retrospective study involved 506 AIS patients from two centers, divided into training (n = 277) and validation (n = 229) cohorts. 4,682 radiomic features were extracted from T1-weighted, T2-weighted, and diffusion-weighted imaging. Logistic regression analysis identified significant clinical risk factors, which, alongside radiomics features, were used to construct a predictive clinical-radiomics nomogram. The model's predictive accuracy was evaluated using calibration and ROC curves, focusing on distinguishing between favorable (mRS ≤ 2) and unfavorable (mRS > 2) outcomes. Results: Key findings highlight coronary heart disease, platelet-to-lymphocyte ratio, uric acid, glucose levels, homocysteine, and radiomics features as independent predictors of AIS outcomes. The clinical-radiomics model achieved a ROC-AUC of 0.940 (95% CI: 0.912-0.969) in the training set and 0.854 (95% CI: 0.781-0.926) in the validation set, underscoring its predictive reliability and clinical utility. Conclusion: The study underscores the efficacy of the clinical-radiomics model in forecasting AIS prognosis, showcasing the pivotal role of artificial intelligence in fostering personalized treatment plans and enhancing patient care. This innovative approach promises to revolutionize AIS management, offering a significant leap toward more individualized and effective healthcare solutions.

Serum proteins differentially expressed in gestational diabetes mellitus assessed using isobaric tag for relative and absolute quantitation proteomics.

BACKGROUND: As a well-known fact to the public, gestational diabetes mellitus (GDM) could bring serious risks for both pregnant women and infants. During this important investigation into the linkage between GDM patients and their altered expression in the serum, proteomics techniques were deployed to detect the differentially expressed proteins (DEPs) of in the serum of GDM patients to further explore its pathogenesis, and find out possible biomarkers to forecast GDM occurrence. AIM: To investigation serum proteins differentially expressed in GDM were assessed using isobaric tag for relative and absolute quantitation (iTRAQ) proteomics and bioinformatics analyses. METHODS: Subjects were divided into GDM and normal control groups according to the IADPSG diagnostic criteria. Serum samples were randomly selected from four cases in each group at 24-28 wk of gestation, and the blood samples were identified by applying iTRAQ technology combined with liquid chromatography-tandem mass spectrometry. Key proteins and signaling pathways associated with GDM were identified by bioinformatics analysis, and the expression of key proteins in serum from 12 wk to 16 wk of gestation was further verified using enzyme-linked immunosorbent assay (ELISA). RESULTS: Forty-seven proteins were significantly differentially expressed by analyzing the serum samples between the GDM gravidas as well as the healthy ones. Among them, 31 proteins were found to be upregulated notably and the rest 16 proteins were downregulated remarkably. Bioinformatic data report revealed abnormal expression of proteins associated with lipid metabolism, coagulation cascade activation, complement system and inflammatory response in the GDM group. ELISA results showed that the contents of RBP4, as well as ANGPTL8, increased in the serum of GDM gravidas compared with the healthy ones, and this change was found to initiate from 12 wk to 16 wk of gestation. CONCLUSION: GDM symptoms may involve abnormalities in lipid metabolism, coagulation cascade activation, complement system and inflammatory response. RBP4 and ANGPTL8 are expected to be early predictors of GDM.

Malposition of a nasogastric feeding tube into the right pleural space of a poststroke patient.

Nasogastric feeding tube plays an important role in administering enteral feeding and drug delivery for poststroke patients with consciousness disorders or poststroke dysphagia. Nevertheless, placement of nasogastric tubes is not without any risk of potential harm. Inadvertent malposition into the trachea or the distal tracheobronchial tree could induce severe pulmonary complications. As for poststroke patients with long-term dysphoria, such tubes have to be replaced periodically to prevent the overdue service of the tubes. Therefore, the risk of feeding tube misplacement into pulmonary system for these patients is increased. Here, we present a case of a 79-year-old poststroke patient with hydropneumothorax induced by malposition of nasogastric tube into the right pleura after routine replacement, accompanied by acute anterior wall myocardial infarction.

Distal locked or unlocked nailing for stable intertrochanteric fractures? A meta-analysis.

BACKGROUND: To date, there are just several studies comparing distal locked nails with distal unlocked nails in treating intertrochanteric fractures. We report the first meta-analysis about this issue. METHODS: Systematic search was conducted for studies in PubMed, Embase and Cochrane Library. Meta-analyses were performed regarding intra operative outcomes, complications and functional outcomes. RESULTS: Pooled results showed insignificant difference between distal locking group and distal unlocking group in hip pain (relative risk (RR) 1.14, 95% confidence interval (CI) 0.59-2.19), distal tip fracture (RR 1.08, 95% CI 0.37-3.11), lag screw cut-out (RR 1.60, 95% CI 0.54-4.78), delayed or nonunion (RR 1.32, 95% CI 0.25-7.06), deep vein thrombosis (RR 1.06, 95% CI 0.23-4.84), wound infection (RR 0.58, 95% CI 0.28-1.22), Harris hip score (standard mean deviation (SMD) 0.03, 95% CI -0.15 to 0.21) and walking ability. However, significant difference was detected in operation time (SMD 0.77, 95% CI 0.36-1.17), fluoroscopy exposure time (SMD 1.02, 95% CI 0.52-1.52), blood loss (SMD 0.80, 95% CI 0.62-0.99) and total incision length (SMD 1.16, 95% CI 0.86-1.47). Result of trial sequential analysis indicated conclusive evidence. CONCLUSION: Current evidence indicates that the distal locked intramedullary nails should not be recommended as routine choice for stable intertrochanteric fractures.

Prevention effect of allopurinol on post-endoscopic retrograde cholangiopancreatography pancreatitis: a meta-analysis of prospective randomized controlled trials.

BACKGROUND: Pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP) which can be severe and cause death in approximately 10% of cases. Up to now, six randomized controlled trials (RCTs) have been found relevant to the effect of allopurinol on prevention of Post-ERCP pancreatitis (PEP). However, these results remained controversial. OBJECTIVE: To conduct a meta-analysis with RCTs published in full text to determine the effectiveness of prophylactic allopurinol of different dosages and administration time in the incidence and severity of PEP. METHODS: Literature search was performed in PubMed, Embase, Web of Science and Cochrane Library from databases inception to May 2014. RCTs comparing the effect of allopurinol with placebo on prevention of PEP were included. Statistical heterogeneity was quantitatively evaluated byχ2 test with the significance set P<0.10 or I2>50%. RESULTS: Six RCTs consisting of 1974 participants were eventually included. The incidences of PEP in allopurinol group and placebo group were 8.4%(83/986) and 9.9%(98/988) respectively. Meta-analysis showed no evident prevention effect of allopurinol on the incidence of PEP (RR 0.75, 95%CI 0.39-1.42) with significant heterogeneity (I2 = 70.4%, P = 0.005). When studies were stratified according to the dosages and administration time of allopurinol they applied, there was still no evident prevention effect of allopurinol on mild, moderate or severe PEP. However, statistically substantial heterogeneity was presented in the subgroup of moderate PEP when the effect of high dose of allopurinol was analyzed (Imoderate2 = 82.3%, Pmoderate = 0.018). Statistically significant heterogeneity was also observed in subgroup of mild PEP, when the effect of long adminstration time of allopurinol was investigated (Imild2 = 62.8%, Pmild = 0.068). CONCLUSION: The prophylactic use of allopurinol in different dosages and administration time had no effect in preventing incidence and severity of PEP.

Potential role of NADPH oxidase in pathogenesis of pancreatitis.

Studies have demonstrated that reactive oxygen species (ROS) are closely related to inflammatory disorders. Nicotinamide adenine dinucleotide phosphate oxidase (NOX), originally found in phagocytes, is the main source of ROS in nonphagocytic cells. Besides directly producing the detrimental highly reactive ROS to act on biomolecules (lipids, proteins, and nucleic acids), NOX can also activate multiple signal transduction pathways, which regulate cell growth, proliferation, differentiation and apoptosis by producing ROS. Recently, research on pancreatic NOX is no longer limited to inflammatory cells, but extends to the aspect of pancreatic acinar cells and pancreatic stellate cells, which are considered to be potentially associated with pancreatitis. In this review, we summarize the literature on NOX protein structure, activation, function and its role in the pathogenesis of pancreatitis.