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Background: Idiopathic cardiac osseous metaplasia in the right atrium of a 9-year-old boy, accompanied by right atrial Chiari network and right pulmonary artery embolism. This case is rare and can easily be misdiagnosed. Case Description: We encountered a case of a 9-year-old boy with a 3.5 cm diameter neoplasm in the right atrium. Preoperative imaging diagnosis could not determine the nature of the tumor, and the initial clinical suspicion of cardiac myxoma. After admission, a cardiotomy to remove foreign bodies and a pulmonary artery thrombectomy were performed. Conclusions: Idiopathic cardiac osseous metaplasia is relatively rare, and it is even rarer to be accompanied by a Chiari network in the right atrium. Due to the location and characteristics of the lesion in this case, it is easy to be misdiagnosed as atrial myxoma in clinical practice. Whether it is idiopathic osseous metaplasia or myxoma, it needs to be performed surgical treatment and pathological examination can easily rule out the diagnosis of myxoma. However, as idiopathic cardiac metaplasia is difficult to encounter in clinical work and there are few reports in the literature, clinicians and pathologists need to consult more relevant literature. Learn to understand and master the disease through multi-party consultation.
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Objective: This study aimed to identify plasma biomarkers that are significantly altered in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and are closely associated with AAV disease activity, as well as to explore their role in the pathogenesis of AAV. Methods: Cytokines were measured using Human Immune Response Panel 80-Plex in plasma from 59 patients with AAV and 20 healthy controls (HCs). The differentially expressed cytokines between the two groups and the possible signaling pathway involved in the pathogenesis of AAV were analyzed by bioinformatics. Relationship analysis was performed between these cytokines and clinical parameters to identify the biomarkers that can effectively indicate disease activity. Results: We identified 65 differentially expressed cytokines between the two groups. Among them, 43 cytokines significantly affected the risk of AAV. Bioinformatic analysis showed that the 43 cytokines were primarily enriched in signaling pathways such as cytokine-cytokine receptor interaction, viral protein interaction with cytokine and cytokine receptor, chemokine signaling pathway, and IL-17 signaling pathway. The levels of 25 cytokines were significantly positively correlated with Birmingham Vasculitis Activity Score (BVAS), and the levels of 2 cytokines were significantly negatively correlated with BVAS. Receiver operating characteristic analysis showed that 9 cytokines can distinguish between disease relapse and remission (PTX3: area under curve (AUC)=0.932, IL34: AUC=0.856, IL2RA: AUC=0.833, CCL23: AUC=0.826, VEGFA: AUC=0.811, TNFSF13: AUC=0.795, Granzyme A: AUC=0.788, CSF3: AUC=0.773 and IL1A: AUC=0.765). The elevated levels of these 9 cytokines suggested a risk of disease relapse. The AUC of CCL11 in disease relapse and remission was 0.811 (p=0.0116). Unlike the other 9 cytokines, a negatively association existed between CCL11 level and the risk of disease relapse. Conclusion: A group of cytokines that may be involved in AAV pathogenesis was identified. Increased PTX3, IL34, IL2RA, CCL23, and VEGFA levels correlate with active disease in AAV and may be used as biomarkers to identify the disease relapse of AAV.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Biomarcadores , Citocinas , Humanos , Masculino , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/sangue , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Feminino , Citocinas/sangue , Pessoa de Meia-Idade , Biomarcadores/sangue , Idoso , Adulto , Estudos de Casos e Controles , Transdução de SinaisRESUMO
Bone marrow (BM) is the dominant site of hematopoiesis after 20 post-conception weeks (PCWs), but the intricacies of hematopoietic development in fetal BM up to birth and its involvement in malignancies remain unknown. Here, we compared the single-cell transcriptomic profile of BM hematopoietic stem and progenitor cells (HSPCs) at the early (12-14 PCW), middle (19-22 PCW) second trimester, and the neonatal stage. The stemness of hematopoietic stem cell and multipotent progenitor (HSC/MPP) is established at the middle second trimester, then maintained until birth. Furthermore, differentiation potentials toward three lineages are enhanced after the middle second trimester for birth, accompanied by the upregulation of aerobic metabolism. Notably, decreased stemness in HSCs/MPPs and higher interferon signals in progenitors at the early second trimester rendered the HSPCs more proximal to leukemogenesis. Collectively, our work elucidated the dynamics of fetal hematopoiesis in preparation for birth, offering valuable insights into the pathological processes underlying leukemia.
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Both the brain-derived neurotrophic factor (BDNF) valine (Val)/methionine (Met) polymorphism and mismatch negativity (MMN) amplitude are reportedly linked to working memory impairments in schizophrenia. However, there is evident scarcity of research aimed at exploring the relationships among the three factors. In this secondary analysis of a randomized, controlled, double-blind trial, we investigated these relationships. The trial assessed the efficacy of transcranial direct current stimulation for enhancing working memory in clinically stable schizophrenia patients, who were randomly divided into three groups: dorsolateral prefrontal cortex stimulation, posterior parietal cortex stimulation, and sham stimulation groups. Transcranial direct current stimulation was administered concurrently with a working memory task over five days. We assessed the BDNF genotype, MMN amplitude, working memory capacity, and interference control subdomains. These assessments were conducted at baseline with 54 patients and followed up post-intervention with 48 patients. Compared to BDNF Met-carriers, Val homozygotes exhibited fewer positive and general symptoms and increased working memory capacity at baseline. A correlation between MMN amplitude and working memory capacity was noted only in BDNF Val homozygotes. The correlations were significantly different in the two BDNF genotype groups. Furthermore, in the intervention group that showed significant improvement in MMN amplitude, BDNF Val homozygotes exhibited greater enhancement in working memory capacity than Met-carriers. This study provides in vivo evidence for the interaction between MMN and BDNF Val/Met polymorphism for working memory capacity. As MMN has been considered a biomarker of N-methyl-D-aspartate receptor (NMDAR) function, these data shed light on the complex interactions between BDNF and NMDAR in terms of working memory in schizophrenia.
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Benign prostatic hyperplasia (BPH) is one of the most common diseases in elderly men, the incidence of which gradually increases with age and leads to lower urinary tract symptoms (LUTS), which seriously affects the quality of life of patients. Chinese herbal medicines (CHMs) are widely used for the treatment of BPH in China and some other countries. To explore the molecular mechanisms of CHMs for BPH, we conducted a review based on peer-reviewed English-language publications in PubMed and Web of Science databases from inception to December 31, 2023. This article primarily reviewed 32 papers on the use of CHMs and its active compounds in the treatment of BPH, covering animal and cell experiments, and identified relevant mechanisms of action. The results suggest that the mechanisms of action of CHMs in treating BPH may involve the regulation of sex hormones, downregulation of cell growth factors, anti-inflammatory and antioxidative effects, inhibition of cell proliferation, and promotion of apoptosis. CHMs also exhibit α-blocker-like effects, with the potential to relax urethral smooth muscle and alleviate LUTS. Additionally, we also reviewed 4 clinical trials and meta-analyses of CHMs for the treatment of BPH patients, which provided initial evidence of the safety and effectiveness of CHMs treatment. CHMs treatment for BPH shows advantages as a multi-component, multi-target, and multi-pathway therapy, which can mitigate the severity of the disease, improve LUTS, and may become a reliable treatment option in the future.
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Despite observational studies suggesting a link between psoriatic disease (including psoriasis and psoriatic arthritis) and migraine, it is unclear whether there is a shared genetic etiology or a causal relationship between the two conditions. We aimed to reveal the genetic overlap and causality using the Mendelian randomization (MR) framework. The genetic analysis utilized summary data from the most extensive European genome-wide association study (GWAS) of migraine. Well-powered psoriatic disease GWAS data were obtained from two independent cohort studies, which served as discovery and validation datasets. Global and regional genetic correlations between psoriatic disease and migraine were assessed, and pleiotropic regions identified by pairwise GWAS analysis were further annotated. We further applied a two-sample MR multivariate MR to investigate the potential causal relationship between them. The global genetic correlation test indicated weak correlations between psoriatic disease and migraine, while regional correlation analyses delineated one significant shared locus between psoriasis and migraine. Pathway enrichment analysis revealed that shared genes were involved biological processes to the major histocompatibility and antigen processing and presentation. In terms of causality estimates, genetically predicted psoriasis (Pmeta = 0.003) and psoriatic arthritis (Pmeta = 0.028) were associated with an increased risk of migraine. Multivariate MR analysis indicated that psoriasis was an independent risk factor for migraine (P < 0.05). No significant associations were found in the reverse direction. Our study supported the causal role of psoriasis on migraine, and the central role for immunomodulatory etiology. These findings have significant implications for the management of migraine and clinical practice in patients with psoriasis.
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Artrite Psoriásica , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Transtornos de Enxaqueca , Polimorfismo de Nucleotídeo Único , Psoríase , Humanos , Transtornos de Enxaqueca/genética , Transtornos de Enxaqueca/epidemiologia , Psoríase/genética , Psoríase/epidemiologia , Artrite Psoriásica/genética , Artrite Psoriásica/epidemiologia , Fatores de RiscoRESUMO
INTRODUCTION: A previous meta-analysis indicated stable progress in cognitive functions in early psychosis, assessed through various tools. To avoid assessment-related heterogeneity, this study aims to examine the longitudinal cognitive function changes in early psychosis utilizing the MATRICS Consensus Cognitive Battery (MCCB). METHODS: Embase, PubMed, and Scopus were systematically searched from their inception to September 26th 2023. The inclusion criteria were longitudinal studies that presented follow-up MCCB data for individuals experiencing first-episode psychosis (FEP) and those with ultra-high risk for psychosis (UHR). RESULTS: Twelve studies with 791 participants (566 FEP patients and 225 healthy controls) were subjected to analysis. Suitable UHR studies were absent. Over time, both FEP patients and healthy controls showed significant improvements in MCCB total scores. Furthermore, FEP patients demonstrated improvements across all MCCB domains, while healthy controls only showed augmentations in specific domains such as speed of processing, attention, working memory, and reasoning and problem-solving. Visuospatial learning improvements were significantly greater in FEP patients compared to healthy controls. Subgroup analyses suggested that neither diagnostic type nor follow-up duration influenced the magnitude of cognitive improvement in FEP patients. CONCLUSION: The magnitude of cognitive improvement for MCCB domains was not significantly different between FEP and healthy controls other than visuospatial learning. This underscores visuospatial learning as a potentially sensitive cognitive marker for early pathologic state changes in psychotic disorders.
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Disfunção Cognitiva , Transtornos Psicóticos , Humanos , Transtornos Psicóticos/fisiopatologia , Transtornos Psicóticos/diagnóstico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/fisiopatologia , Estudos Longitudinais , Testes Neuropsicológicos , AdultoRESUMO
Convincing evidence suggests that aberrant gut microbiota changes play a critical role in the progression and pathogenesis of inflammatory bowel disease (IBD). Probiotic therapeutic interventions targeting the microbiota may provide alternative avenues to treat IBD, but currently available probiotics often suffer from low intestinal colonization and limited targeting capability. Here, we developed azido (N3)-modified Prussian blue nanozyme (PB@N3) spatio-temporal guidance enhances the targeted colonization of probiotics to alleviate intestinal inflammation. First, clickable PB@N3 targets intestinal inflammation, simultaneously, it scavenges reactive oxygen species (ROS). Subsequently, utilizing "click" chemistry to spatio-temporally guide targeted colonization of dibenzocyclooctyne (DBCO)-modified Lactobacillus reuteri DSM 17938 (LR@DBCO). The "click" reaction between PB@N3 and LR@DBCO has excellent specificity and efficacy both in vivo and in vitro. Despite the complex physiological environment of IBD, "click" reaction can prolong the retention time of probiotics in the intestine. Dextran sulfate sodium (DSS)-induced colitis mice model, demonstrates that the combination of PB@N3 and LR@DBCO effectively mitigates levels of ROS, enhances the colonization of probiotics, modulates intestinal flora composition and function, regulates immune profiles, restores intestinal barrier function, and alleviates intestinal inflammation. Hence, PB@N3 spatio-temporal guidance enhances targeted colonization of LR@DBCO provides a promising medical treatment strategy for IBD.
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In order to improve the functionality of natural gelatin films for active food packaging applications, a combined strategy of crosslinking via Maillard reaction and blending enhancement incorporated with poly(vinyl alcohol) (PVA) was explored. In this study, when the mass ratio of gelatin to glucose was 10:1, Maillard reaction of crosslinked gelatin films was the highest, UV absorption and browning index reached the maximum. Infrared analysis showed that PVA could form strong interfacial interactions with gelatin matrix. The presence of PVA could significantly improve the toughness, water absorption, transparency, and oxygen barrier properties of crosslinked gelatin films. When the amount of PVA reached 5 %, elongation at break and oxygen barrier properties of crosslinked gelatin films were improved by 76.7 % and 47.9 % compared with pure crosslinked gelatin film. Even when the amount of PVA reached 10 %, UV absorption (at 315 nm) of crosslinked gelatin films still exceeded 98.7 %. The addition of PVA could accelerate the dissolution and swelling of crosslinked gelatin films, promoting the migration and release of active substances (Maillard reaction products (MRPs)). The two antioxidant activities tests (DPPH and ABTS method) achieved the highest radical scavenging rates of 71.6 % and 91.2 %, respectively, with corresponding PVA addition of 5 % and 7.5 %. After continuing to add PVA, antioxidant activities began to significantly decrease, which was directly related to the decrease in the generation of MRPs. Therefore, crosslinked gelatin films reinforced with appropriate amount of PVA can be considerable potential as active films for renewable food packaging applications.
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Antioxidantes , Embalagem de Alimentos , Gelatina , Reação de Maillard , Álcool de Polivinil , Gelatina/química , Embalagem de Alimentos/métodos , Álcool de Polivinil/química , Antioxidantes/química , Reagentes de Ligações Cruzadas/química , Água/químicaRESUMO
BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a growing health crisis in the general population of the United States (U.S.), but the relationship between systemic immune-inflammation (SII) index and NAFLD is not known. METHODS: We collected data from the National Health and Nutrition Examination Survey 2017-2018. Next, propensity score matching (PSM), collinearity analysis, restricted cubic spline (RCS) plot, logistic regression, quantile regression analysis, subgroup analysis, mediation analysis, and population attributable fraction were used to explore the association of the SII with risk of NAFLD. RESULTS: A total of 665 participants including the 532 Non-NAFLD and 133 NAFLD were enrolled for further analysis after PSM analysis. The RCS results indicated that there was a linear relationship between the SII and controlled attenuation parameter (p for nonlinear = 0.468), the relationship also existed after adjustment for covariates (p for nonlinear = 0.769). The logistic regression results indicated that a high SII level was an independent risk factor for NAFLD (OR = 3.505, 95% CI: 1.092-11.249, P < 0.05). The quantile regression indicated that at higher quantiles (0.90, and 0.95) the SII was significantly associated with NAFLD (p < 0.05). Mediation analysis indicated that alanine aminotransferase (ALT), triglycerides, and blood urea nitrogen (BUN) were partially contribute to the relationship between SII and NAFLD. The population attributable fractions indicated that 23.19% (95% CI: 8.22%, 38.17%) of NAFLD cases could be attributed to SII corresponding to 133 NAFLD cases. CONCLUSION: There was a positive linear relationship between the SII and the risk of NAFLD. The ALT, triglycerides, and BUN had a partial mediating effect on the relationship between the SII and NAFLD.
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Inflamação , Hepatopatia Gordurosa não Alcoólica , Inquéritos Nutricionais , Humanos , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/sangue , Feminino , Masculino , Adolescente , Estados Unidos/epidemiologia , Fatores de Risco , Inflamação/imunologia , Inflamação/sangue , Pontuação de Propensão , Modelos Logísticos , Alanina Transaminase/sangueRESUMO
OBJECTIVE: To develop and validate a population pharmacokinetic (PPK) model of oral olanzapine in pediatric Chinese patients in order to individualize therapy in this population. METHODS: A total of 897 serum concentrations from 269 pediatric patients taking oral olanzapine (ages 8-17 years) were collected. Demographic parameters, biological characteristics and concomitant medications were investigated as covariates. The data were analyzed using a nonlinear mixed-effects modeling approach. Bootstrapping (1000 runs), normalized prediction distribution error (NPDE), and external validation of 62 patients were employed. Simulations were performed to explore the individualized dosing regimens in various situations. RESULTS: The one-compartment model with first-order absorption and elimination had an apparent clearance (CL/F) of 10.38 L/h, a distribution volume (V/F) of 9.41 L/kg and an absorption rate constant (Ka) fixed at 0.3 h-1. The equation was CL∕F (L∕h) = 10.38 × (body weight∕60)0.25 ×1.33 (if male) × 0.71 (if co-occurrence of infection) × 0.51 (if co-therapy with fluvoxamine) × 1.27 (if co-therapy with sertraline) × 1.43 (if co-therapy with valproate). The final model had satisfactory stability, robustness, and predictive ability. The results from a simulation suggested the oral olanzapine doses required for male and female pediatric patients weighing between 40 and 60 kg without co-medication were 10-15 mg/day and 7.5-10 mg/day, respectively, and dosage adjustments should be based on sex and body weight; and co-administrated with valproate, sertraline, or fluvoxamine. CONCLUSION: This model may help individualize optimum dosing of oral olanzapine for pediatric patients.
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Working memory deficits are linked to irregularities in the dorsolateral prefrontal cortex (DLPFC) and the posterior parietal cortex (PPC) in schizophrenia, effective intervention strategies are lacking. We evaluated the differential efficacy and underlying neuromechanisms of targeting transcranial direct current stimulation (tDCS) at the DLPFC and the PPC with concurrent cognitive performance for working memory in schizophrenia. In a randomized and double-blind clinical trial, sixty clinically stable schizophrenic patients with below-average working memory were randomly assigned to active DLPFC, active PPC, and sham tDCS groups. Two sessions of tDCS during N-back task were delivered daily for five days. The primary outcome was changes in spatial span test scores from baseline to week 1. The secondary outcomes included changes in scores of color delay-estimation task, other cognitive tasks, and mismatch negativity (biomarker of N-methyl-d-aspartate receptor functioning). Compared with the active DLPFC group, the active PPC group demonstrated significantly greater improvement in spatial span test scores (p = 0.008, d = 0.94) and an augmentation in color delay-estimation task capacity at week 1; the latter sustained to week 2. Compared with the sham tDCS group, the active PPC group did not show a significant improvement in spatial span test scores at week 1 and 2; however, significant enhancement was observed in their color delay-estimation task capacity at week 2. Additionally, mismatch negativity amplitude was enhanced, and changes in theta band measures were positively correlated with working memory improvement in the active PPC group, while no such correlations were observed in the active DLPFC group or the sham tDCS group. Our results suggest that tDCS targeting the PPC relative to the DLPFC during concurrent cognitive performance may improve working memory in schizophrenia, meriting further investigation. The improvement in working memory appears to be linked to enhanced N-methyl-d-aspartate receptor functioning.
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Memória de Curto Prazo , Lobo Parietal , Córtex Pré-Frontal , Esquizofrenia , Estimulação Transcraniana por Corrente Contínua , Humanos , Memória de Curto Prazo/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Esquizofrenia/terapia , Esquizofrenia/fisiopatologia , Masculino , Feminino , Adulto , Método Duplo-Cego , Lobo Parietal/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Córtex Pré-Frontal Dorsolateral/fisiologia , Pessoa de Meia-Idade , Resultado do Tratamento , Cognição/fisiologia , Adulto Jovem , Testes NeuropsicológicosRESUMO
BACKGROUND: Conventional five-port laparoscopic surgery, the current standard treatment for colorectal carcinoma (CRC), has many disadvantages. AIM: To assess the influence of reduced-port laparoscopic surgery (RPLS) on perioperative indicators, postoperative recovery, and serum inflammation indexes in patients with CRC. METHODS: The study included 115 patients with CRC admitted between December 2019 and May 2023, 52 of whom underwent conventional five-port laparoscopic surgery (control group) and 63 of whom underwent RPLS (research group). Comparative analyses were performed on the following dimensions: Perioperative indicators [operation time (OT), incision length, intraoperative blood loss (IBL), and rate of conversion to laparotomy], postoperative recovery (first postoperative exhaust, bowel movement and oral food intake, and bowel sound recovery time), serum inflammation indexes [high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6)], postoperative complications (anastomotic leakage, incisional infection, bleeding, ileus), and therapeutic efficacy. RESULTS: The two groups had comparable OTs and IBL volumes. However, the research group had a smaller incision length; lower rates of conversion to laparotomy and postoperative total complication; and shorter time of first postoperative exhaust, bowel movement, oral food intake, and bowel sound recovery; all of which were significant. Furthermore, hs-CRP, IL-6, and TNF-α levels in the research group were significantly lower than the baseline and those of the control group, and the total effective rate was higher. CONCLUSION: RPLS exhibited significant therapeutic efficacy in CRC, resulting in a shorter incision length and a lower conversion rate to laparotomy, while also promoting postoperative recovery, effectively inhibiting the inflammatory response, and reducing the risk of postoperative complications.
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BACKGROUND: The combination of magnetic compression anastomosis (MCA) and endoscopy has been used to treat biliary stricture after liver transplantation. However, its use for the treatment of complex biliary obstruction after major abdominal trauma has not been reported. This case report describes the successful use of MCA for the treatment of biliary obstruction resulting from major abdominal trauma. CASE SUMMARY: A 23-year-old man underwent major abdominal surgery (repair of liver rupture, right half colon resection, and ileostomy) following a car accident one year ago. The abdominal drainage tube, positioned at the Winslow foramen, was draining approximately 600-800 mL of bile per day. During the two endoscopic retrograde cholangiopancreatography procedures, the guide wire was unable to enter the common bile duct, which prevented placement of a biliary stent. MCA combined with endoscopy was used to successfully achieve magnetic anastomosis of the peritoneal sinus tract and duodenum, and then a choledochoduodenal stent was placed. Finally, the external biliary drainage tube was removed. The patient achieved internal biliary drainage leading to the removal of the external biliary drainage tube, which improved the quality of life. CONCLUSION: Magnetic compression technique can be used for the treatment of complex biliary obstruction with minimal operative trauma.
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BACKGROUND: The treatment of postoperative anastomotic stenosis after excision of rectal cancer is challenging. Endoscopic balloon dilation and radial incision are not effective in all patients. We present a new endoscopy-assisted magnetic compression technique (MCT) for the treatment of rectal anastomotic stenosis. We successfully applied this MCT to a patient who developed an anastomotic stricture after radical resection of rectal cancer. CASE SUMMARY: A 50-year-old man had undergone laparoscopic radical rectal cancer surgery at a local hospital 5 months ago. A colonoscopy performed 2 months ago indicated that the rectal anastomosis was narrow due to which ileostomy closure could not be performed. The patient came to the Magnetic Surgery Clinic of the First Affiliated Hospital of Xi'an Jiaotong University after learning that we had successfully treated patients with colorectal stenosis using MCT. We performed endoscopy-assisted magnetic compression surgery for rectal stenosis. The magnets were removed 16 d later. A follow-up colonoscopy performed after 4 months showed good anastomotic patency, following which, ileostomy closure surgery was performed. CONCLUSION: MCT is a simple, non-invasive technique for the treatment of anastomotic stricture after radical resection of rectal cancer. The technique can be widely used in clinical settings.
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The CoCrFeMnNi high-entropy alloy is commonly used for vascular stents due to its excellent mechanical support and ductility. However, as high-entropy alloy stents can cause inflammation in the blood vessels, leading to their re-narrowing, drug-eluting stents have been developed. These stents have nanopores on their surfaces that can carry drug particles to inhibit inflammation and effectively prevent re-narrowing of the blood vessels. To optimize the mechanical properties and drug-carrying capacity of high-entropy alloy stents, a high-entropy alloy system with different wide and deep square-shaped nanopore distributions is created using molecular dynamics. The mechanical characteristics and dislocation evolution mechanism of different nanopore high-entropy alloy systems under tensile stress were studied. The results showed that the CoCrFeMnNi high-entropy alloy with a rational nanopore distribution can effectively maintain the mechanical support required for a vascular stent. This research provides a new direction for the manufacturing process of nanopores on the surfaces of high-entropy alloy stents.
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The vibrations in functionally graded porous Cu-Si microcantilever beams are investigated based on physical neutral plane theory, modified coupled stress theory, and scale distribution theory (MCST&SDT). Porous microcantilever beams define four pore distributions. Considering the physical neutral plane theory, the material properties of the beams are computed through four different power-law distributions. The material properties of microcantilever beams are corrected by scale effects based on modified coupled stress theory. Considering the fluid driving force, the amplitude-frequency response spectra and resonant frequencies of the porous microcantilever beam in three different fluids are obtained based on the Euler-Bernoulli beam theory. The quality factors of porous microcantilever beams in three different fluids are derived by estimating the equation. The computational analysis shows that the presence of pores in microcantilever beams leads to a decrease in Young's modulus. Different pore distributions affect the material properties to different degrees. The gain effect of the scale effect is weakened, but the one-dimensional temperature field and amplitude-frequency response spectra show an increasing trend. The quality factor is decreased by porosity, and the degree of influence of porosity increases as the beam thickness increases. The gradient factor n has a greater effect on the resonant frequency. The effect of porosity on the resonant frequency is negatively correlated when the gradient factor is small (n<1) but positively correlated when the gradient factor is large (n>1).
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ß-Ga2O3 is an ultrawide-band gap semiconductor with excellent potential for high-power and ultraviolet optoelectronic device applications. Low thermal conductivity is one of the major obstacles to enable the full performance of ß-Ga2O3-based devices. A promising solution for this problem is to integrate ß-Ga2O3 with a diamond heat sink. However, the thermal properties of the ß-Ga2O3/diamond heterostructures after the interfacial bonding have not been studied extensively, which are influenced by the crystal orientations and interfacial atoms for the ß-Ga2O3 and diamond interfaces. In this work, molecular dynamics simulations based on machine learning potential have been adopted to investigate the crystal-orientation-dependent and interfacial-atom-dependent thermal boundary resistance (TBR) of the ß-Ga2O3/diamond heterostructure after interfacial bonding. The differences in TBR at different interfaces are explained in detail through the explorations of thermal conductivity value, thermal conductivity spectra, vibration density of states, and interfacial structures. Based on the above explorations, a further understanding of the influence of different crystal orientations and interfacial atoms on the ß-Ga2O3/diamond heterostructure was achieved. Finally, insightful optimization strategies have been proposed in the study, which could pave the way for better thermal design and management of ß-Ga2O3/diamond heterostructures according to guidance in the selection of the crystal orientations and interfacial atoms of the ß-Ga2O3 and diamond interfaces.
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Obstructive sleep apnea (OSA) has received considerable attention as a potential risk factor for depressive symptoms. The systematic review was conducted to confirm the doseâresponse connection between OSA severity and depression risk. A systematic literature search of English and Chinese articles published in PubMed, EMBASE, Scopus, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), and SinoMed databases from their inception to 28 August 2023 was conducted. An evaluation using the NewcastleâOttawa Scale was performed. A meta-analysis was used to evaluate the impact of OSA severity. A random-effects doseâresponse model was conducted to evaluate the linear and nonlinear doseâresponse connections. We evaluated publication bias by funnel plots, and symmetry by Egger's test. We identified 18 cross-sectional researches. 3143 participants which were involved in the doseâresponse meta-analysis. Contrasted with mild OSA, individuals with severe OSA had a higher adjusted risk of depression (rate ratio: 1.34, 95% confidence interval = 1.05-1.70), with substantial heterogeneity (I2 = 70.9%, Pheterogeneity<0.001). There is a significant linear connection between OSA severity and depression risk. The depression risk increased by 0.4% for every 1 event per hour increase in the apnea-hypopnea index (AHI). The protocol for this unfunded research was drafted and registered at PROSPERO (ID CRD42023474097).