Science Progress最新文献

There are several factors that influence the mechanisms underlying human injuries in vehicle-to-pedestrian crashes (VTPCs). Traditional multibody system (MBS) models can simulate the entire VTPC process; however, they cannot fully and accurately assess the degree of injury to each part of the head. Therefore, a finite element (FE) model of the head with a complete brain structure is developed based on the 50th-percentile Chinese male data. First, the complete kinematic response of pedestrians in a VTPC is simulated using the MBS model, and the head kinematic response parameters that are most related to pedestrian injury are explored. An FE of the head model is subsequently established based on computed tomography (CT) and magnetic resonance imaging (MRI) data from a 50th-percentile Chinese male. Head-injury-related parameters are input into the head FE model, and orthogonal experiments are designed to analyze the head-to-windshield impact. The results show that impact velocity, position, and angle strongly affect the biological injury parameters of the head. These findings reveal the mechanisms of head injuries in pedestrians in VTPCs and the biomechanical dynamic response characteristics of the main parts of the head.

Currently, purely deep learning-based agents struggle to make optimal decisions within a short timeframe in problems with a vast decision-making space. Human planning knowledge is required to assist agents in making better decisions. This manuscript proposes a novel knowledge-guided and data-driven decision-making framework, utilizing hierarchical task network as the carrier of knowledge, deep learning as the trainer for data, and the Monte Carlo Tree Search as the connector between hierarchical task network and deep learning. The experiments on the MiniRTS environment validated that the proposed framework in this manuscript can replace humans in collecting high-quality data, and it can train neural networks that perform equally well as the compared network even with only 20% of the available data, which provide a new direction for future research.

Urological stones are the common urological diseases in clinical practice. So far, the mechanisms of kidney stone formation still remain unclear. Among all of the mechanisms, the supersaturated crystallization theory focuses on the microcrystal size of stones. However, there are few researches on the formation mechanism of stones in nanoscale. This narrative review summarizes the current mainstream mechanisms of kidney stone formation. It also discusses the relationship between calcium oxalate (CaOx) nanocrystals and the formation of kidney stones from the perspective of the physicochemical properties of the nanocrystals. To further explore the role of CaOx nanocrystals in the formation of CaOx, this review lists some convenient and reliable methods for tracking nanocrystals. Currently, in addition to mainstream treatments like potassium sodium hydrogen citrate and thiazide diuretics, some researches indicate that polysaccharide drugs, selenium nanoparticles, and dietary can inhibit the formation of nanocrystals, ultimately preventing the formation of CaOx stones.

ObjectiveThe aim is to enhance clinician awareness of the disease, reduce the risk of misdiagnosis, and analyze the risk factors for the progression of Chlamydia psittaci infection to severe pneumonia.MethodsWe conducted a retrospective analysis of the clinical data from patients infected with Chlamydia psittaci at our hospital.ResultsThirty-three patients diagnosed with Chlamydia psittaci pneumonia were included in this study. Among them, 23 (72.2%) were male and 10 (27.8%) were female, with a mean age of 59.1 ± 11.1 years. Twenty-four patients (72.7%) had a clear history of poultry exposure. The main clinical manifestations were high fever (n = 30, 90.9%), cough (n = 28, 84.8%), chill (n = 24, 72.7%), expectoration (n = 22, 66.7%), fatigue (n = 20, 60.6%), poor appetite (n = 20, 60.6%), dyspnea (n = 13, 39.4%), and myalgia (n = 10, 30.3%). The lymphocyte count in severe pneumonia group was significantly lower than that in non-severe pneumonia group. C-reactive protein, erythrocyte sedimentation rate, and lactate dehydrogenase levels in the severe group were remarkably higher than those in the non-severe group. The common imaging findings included flake high-density shadows (n = 29, 87.9%), consolidation (n = 20, 60.6%), pleural effusion (n = 17, 51.5%), bronchial inflation signs (n = 15, 45.5%), and ground-glass exudation (n = 20, 60.6%). The majority of patients received treatment with either doxycycline alone, quinolones alone, or a combination of doxycycline and quinolones.ConclusionHistory of contact with birds or poultry, repeated high fever, and flake high-density shadows with consolidation in Chest computed tomography can serve as important indicators for diagnosing C. psittaci pneumonia. Lower lymphocyte counts were identified as the sole risk factor associated with severe C. psittaci pneumonia. Quinolones and doxycycline are effective treatments for C. psittaci pneumonia.

ObjectiveTo evaluate the effectiveness of dental guards in preventing incisor injuries during direct laryngoscopy in microlaryngeal surgery (MLS).Study designNonrandomized retrospective comparative study.MethodsBetween 2022 and 2024, 50 patients who underwent elective MLS using a dental guard were consecutively selected as the dental guard group, and another 50 patients who underwent surgery without a dental guard were selected as the control group. A standardized silicone dental guard was applied to the maxillary incisors of the experimental group. An independent dentist conducted postoperative dental evaluations to assess incisor mobility and enamel damage.ResultsThe experimental group demonstrated significantly lower rates of dental injury (2% vs. 20%) compared with those of the control group. No adverse events related to dental guard use were reported.ConclusionDental guards effectively reduced the incidence of incisor injuries during direct laryngoscopy. Routine use is recommended to minimize perioperative dental complications.

ObjectiveIn recent years, the pericapsular nerve group (PENG) block and anterior quadratus lumborum block (aQLB) have emerged as regional anesthesia techniques commonly used for pain control after hip surgery. This study compared their analgesic efficacy during the first 48 hours following surgery under spinal anesthesia.MethodsIn this prospective, randomized, single-blinded study, patients were assigned to either the PENG (n = 43) or the aQLB group (n = 30). The primary outcome of the study was the total tramadol consumption within the first 48 hours postoperatively. Secondary outcomes included time to first rescue analgesia, resting and dynamic NRS pain scores at 2, 12, 24, and 48 hours postoperatively, and the incidence of complications.ResultsIn this study, postoperative tramadol consumption within the first 48 hours was significantly lower in the PENG (96.74 ± 77.36 mg) compared to the aQLB group (196.33 ± 157.43 mg) (p = 0.004). Additionally, the time to first rescue analgesia was significantly longer in the PENG (9.03 ± 7.67 hours) than in the aQLB group (6.81 ± 6.70 hours) (p = 0.048). NRS scores were similar between the groups at all time points. Quadriceps weakness was not observed in any patient.ConclusionThe PENG block provides effective postoperative analgesia without causing motor blockade, making it advantageous for early mobilization in patients undergoing hip surgery. It can be used as a part of multimodal analgesia.

Chronic mountain sickness (CMS), first described by Carlos Monge Medrano in 1925, is characterized by excessive erythrocytosis (EE), hypoxemia, and neurocognitive disturbances in long-term high-altitude residents. This narrative review revisits Monge's contribution in the light of modern research. CMS is now recognized worldwide, where genetic predisposition and environmental stressors jointly shape susceptibility to high-altitude life. Although hypoxia-driven erythropoietin (EPO) stimulation has long been considered the primary mechanism, recent evidence highlights the critical role of sex hormones in modulating erythropoiesis. EE, once the defining feature, is now complemented by symptom-based scoring systems that better capture the syndrome. Testosterone promotes erythroid expansion by stimulating progenitors, enhancing EPO sensitivity, and suppressing hepcidin, whereas estrogens counteract these effects by downregulating GATA1 and modulating hypoxia-inducible pathways. Elevated testosterone or high testosterone-to-estradiol ratios correlate with hemoglobin, hematocrit, and EE in CMS, explaining its greater prevalence and severity in men. Advances in molecular biology have identified the hypoxia-testosterone-EPO axis, with regulators such as SENP1 and GATA1, as central to disease susceptibility. Excessive androgenic signaling also worsens sleep-disordered breathing and cognitive dysfunction, while estrogenic modulation appears protective, opening avenues for prevention and therapy. In conclusion, CMS should be regarded as a multifactorial disorder shaped by hypoxia, hormones, gene-environment interactions, and cellular stress. Despite progress, underdiagnosis and limited healthcare attention in South American highlands remain major challenges, underscoring the relevance of Monge's seminal description.

ObjectivesThis study aims to investigate the significance of tumor microenvironment (TME)-related genes and signal transduction pathways in head and neck cancer (HNC).MethodsGene expression and clinical data of HNC patients were obtained from the Cancer Genome Atlas (TCGA) database. Differentially expressed genes (DEGs) were screened through a multi-step filtration approach to obtain candidate predictors. The biological role of COL5A1 in HNC was verified through rigorous bioinformatic analysis, experimental validation using quantitative real-time PCR (qRT-PCR), immunohistochemical (IHC) analysis from HNC samples, and IHC data from the Human Protein Atlas (HPA) database.ResultsCOL5A1 was significantly upregulated in HNC tissues and cell lines. High COL5A1 expression was significantly associated with advanced tumor grade (P < .05) and shorter survival (TCGA: P < .001; GSE42743: P = .004). COL5A1 was an independent prognostic indicator (univariate analysis: HR = 1.324, P = .001; Multivariate analysis: HR = 1.326, P = .005). It was enriched in pathways related to tumor invasion and immune responses, and its expression was associated with decreased levels of CD8+ T cells and increased levels of macrophages and neutrophils. Spatial distribution analysis revealed higher expression at the tumor's leading edge (vs. tumor core: P < .001). COL5A1 expression is associated with tumor stage, with more pronounced expression in advanced-stage tumors.ConclusionCOL5A1 represented a novel potential prognostic indicator and therapeutic target in an HNC database sample, as its expression is closely linked to tumor progression, immune cell infiltration, and adverse clinical outcomes. These findings, primarily derived from squamous cell carcinoma-dominated cohorts, warrant further functional validation.

Yellow Fever (YF) is a vector-borne flavivirus infection that can rapidly evolve into fulminant hepatic failure (FHF), a condition associated with high mortality and severe neurological complications, including intracranial hemorrhage (ICH). Early identification of such complications remains a clinical challenge, especially in critically ill patients where the neurological examination is often limited. We present the case of a 60-year-old male with laboratory-confirmed YF by reverse transcription polymerase chain reaction, who developed ICH during the course of his illness. The implementation of a multimodal neuromonitoring approach-including near-infrared spectroscopy, transcranial Doppler, and jugular venous oxygen saturation-enabled the early detection of cerebral hemodynamic and perfusion changes suggestive of intracranial pathology. Despite the timely recognition of ICH, the patient's rapidly deteriorating coagulopathy, driven by FHF, precluded successful intervention, culminating in brain death. This case highlights the value of integrating advanced neuromonitoring modalities in the intensive care setting to enable prompt identification of life-threatening neurological complications. Although not sufficient to alter the fatal trajectory in this instance, early neuromonitoring may offer a critical window for therapeutic decision-making in patients with severe YF. Future research is needed to define standardized neuromonitoring protocols and to evaluate their impact on outcomes in this high-risk population.

The diagnosis of multiple sclerosis (MS) predominantly hinges on the 2017 McDonald criteria, integrated with adjunctive diagnostic modalities including cerebrospinal fluid (CSF) analysis and magnetic resonance imaging (MRI). Notwithstanding their utility, these established methods exhibit inherent limitations in fully elucidating the complex histopathological transformations characteristic of MS. Specifically, they encounter difficulties in precisely quantifying and standardizing patient-specific pathological features, and often lack the requisite precision to delineate the disease's nuanced pathological hallmarks. Recent advancements in neuroimaging, biomarker discovery, and genomic profiling have yielded substantial evidence implicating glial cell activation as a central pathogenic mechanism in MS. In particular, the activation of astrocytes and microglia has been shown to play a pivotal role in disease progression, precipitating a cascade of events that culminate in neuronal axonal demise. The identification of distinct glial cell subsets represents a critical step towards the development of targeted therapeutic strategies. Biomarker-based approaches offer a powerful paradigm for in-vivo interrogation of disease processes, facilitating a more comprehensive understanding of MS pathophysiology and potentially paving the way for personalized treatment modalities. This paper provides a comprehensive overview of the current research on the pathophysiology of glial cells in MS, emphasizing newly identified biomarkers with potential value related to the damage of microglia and astrocytes in MS in recent years.