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Objective To investigate the effect of cerebrospinal fluid (CSF) metagenomic next - generation sequencing (mNGS) in diagnosis and treatment of intracranial infection. Methods A retrospective analysis of 117 patients with intracranial infection were admitted to Shenzhen Second People's Hospital from January 2020 to December 2022. Before initiating empirical broad - spectrum antibiotic treatment, CSF samples were collected for microbial culture (conventional culture group, n = 58) and/or mNGS (mNGS group, n = 59). The results were used to adjust the antibiotic treatment plan, and the study compared the pathogen detection rates and result reporting times of the two testing methods, as well as the antibiotic intensity grading, the intensive care unit (ICU) stay, total hospital stay, and mortality rate. Results A total of 65 pathogens were detected from the CSF samples of all the patients through microbial culture and/or mNGS, with viruses being the most prevalent, accounting for 49.23% (32/65), followed by Gram-negative bacteria (24.62%, 16/65), Gram-positive bacteria (18.46%, 12/65) and fungi (7.69%, 5/65). The pathogen detection rate of CSF mNGS was higher than that of CSF microbial culture (χ2 = 22.781, P = 0.000), and the results were reported earlier (t = - 32.588, P = 0.000). Based on the results, 20 cases (33.90%) in the mNGS group adjusted antibiotic treatment plan, with 5 cases downgrading and 15 cases upgrading the intensity of antibiotic application. In the conventional culture group, 30 cases (51.72%) adjusted their antibiotic treatment plan, with 17 cases downgrading and 13 cases upgrading the intensity of antibiotic application. There was no significant difference between the 2 groups (Z = - 1.917, P = 0.055). And there was no statistically significant difference in ICU stay (Z = - 0.716, P = 0.474）, total hospital stay (Z = - 0.933, P = 0.351) and mortality rate (Fisher's exact probability: P = 0.496) between the 2 groups. Conclusions The application of mNGS can effectively improve the detection rate of intracranial infection pathogens, which may shorten the duration of antibiotic use and reduce the intensity of broad - spectrum antibiotics, so as to help clinical effective judgment and treatment decision.

Objective To investigate the efficacy of cluster therapy in the treatment of severe intracranial infection. Methods The clinical data of 43 patients with severe intracranial infection in Shenzhen University General Hospital and Shenzhen Second People's Hospital from July 2020 to June 2023 were retrospectively analyzed. Patients with intracranial infection were treated with cluster therapy: systemic broad-spectrum antibiotics were used at first; cerebrospinal fluid was obtained by multiple drainage routes for routine and biochemical testing, and then cultured and undertook next - generation sequencing (NGS); head/chest CT and brain MRI plain and enhanced scan were performed; after the NGS results were reported, precisely adjust the drug treatment according to the infection pathogen; sequentially use different drainage protocols of infected cerebrospinal fluid. Patients with severe intraventricular inflammation were treated with ventriculoscope (flexible endoscope) irrigation and fistula; cerebrospinal fluid, microbial culture and whole blood test for infection indicators were regularly extracted for laboratory test, and the type and dosage of antibiotics were adjusted one week after the indicators returned to normal, and the treatment effect of patients was judged comprehensively according to blood, cerebrospinal fluid, imaging results and clinical signs of infection. Results Sixteen patients were administered a broad - spectrum antibiotic regimen consisting of meropenem and vancomycin. Cerebrospinal fluid analysis revealed that 12 cases (27.91%) were culture-positive for microbial organisms (bacteria, fungi, viruses), while 35 cases (81.40%) yielded positive results in NGS. Upon identification of the pathogen via NGS, 15 cases were switched to targeted, sensitive antibiotics, with 12 cases exhibiting notable improvements in symptoms, and 3 cases demonstrating no significant changes. A total of 27 patients (62.79%) underwent surgical intervention, including 7 patients (16.28%) who underwent abscess puncture drainage, 6 patients (13.95%) who received Ommaya sac implantation, 11 patients (25.58%) who underwent external ventricular drainage (8 of whom also underwent ventriculoscopic irrigation and ventriculostomy), and 3 patients (6.98%) who were treated with lumbocisterna drainage. The length of hospitalization was 30 (19, 57) d. The 37 cases (86.05%) were successfully cured, while 6 cases (13.95%) died. Conclusions The cure rate of patients with severe intracranial infection was significantly improved after cluster therapy, and early initiation of cluster therapy can significantly improve the prognosis of patients, which is worthy of clinical application.

Vacuum induction-melting gas atomization (VIGA) is considered a widely applied method to prepare metal powders. However, the nozzle clogging problem in the VIGA process seriously affects the continuity of production and greatly increases the economic and time costs. In the atomization initial stage, the existence of unsteady state atomization mainly results in the nozzle clogging challenge. To understand the formation mechanism of nozzle clogging, a computational fluid dynamics (CFD) model was established to simulate the influence of unsteady state atomization sequence on the primary atomization of alloy melt. Typically, there are two kinds of sequence including starting the gas before pooling the alloy (namely, GA) and pouring the alloy before opening the gas (AG). The movement trajectory of the alloy melt droplet at the end of the delivery-tube was clarified. Based on CFD simulation, the atomization sequence of AG and GA was precisely controlled in the atomization pressure range of 2.5 MPa, 3.5 MPa, and 4.5 MPa to address the nozzle clogging issue. In the GA process, relatively finer powder was obtained at 3.5 MPa without nozzle clogging occurring. In contrast, the AG process greatly reduces the probability of nozzle clogging at 2.5–4.5 MPa, the final prepared powder is coarser. The predicted results of industrial experiments and numerical simulations are consistent. This study provides theoretical support for understanding the formation mechanism of nozzle clogging during the VIGA process.

IntroductionTraumatic brain injury (TBI) seriously affects the quality of human health and the prognosis of the patient, but the epidemiological characteristics of TBI can vary among populations. Numerous changes have occurred in the epidemiological characteristics of individuals with TBI in the fast-paced city of Shenzhen, China. However, little is known about these characteristics. This study aimed to investigate the changes in TBI epidemiology, help clinicians improve medical treatment.MethodsIn this retrospective cross-sectional analysis, we collected the data of 4,229 patients with TBI admitted to 20 hospitals in Shenzhen in 2017. We collected data on age, gender, cause and severity of the injury, eventual diagnosis, time from injury to admission in a neurosurgery department, and patient outcomes. Two neurosurgeons simultaneously collected the data. We compared these results with a similar study conducted in Shenzhen during the period from 1994 to 2003 to clarify and explain the changes in the epidemiological characteristics of TBI.ResultsThe majority of respondents were men [2,830 (66.9%)]. The mean age was 32.5 ± 21.4 years. The youngest patient was less than 1 year old, and the oldest patient was 101 years old. A total of 3,947 (93.3%) patients had a favorable outcome, 219 (5.2%) had an unfavorable outcome, and 63 (1.5%) died. The predominant external cause was falls (1,779 [42.1%]); this was the most common cause of TBI in children and older adults. Riders of electric bicycles (423 [29.0%]) were the most vulnerable to traffic accident-related injuries. Time greater than 50 h from injury to admission to a neurosurgical department had a significant effect on prognosis (p

Hydrogen via direct seawater splitting is a viable option, but anodic oxygen evolution reaction (OER) faces challenges when seawater is used, and to realize seawater splitting at full potential, efficient and effective catalysts are needed. Here, we introduced a unique two-dimensional molybdenum oxide@iron oxide (MO@FO) heterostructure synthesized via a simple hydrothermal process for anodic OER in alkaline seawater. Chemically bonded two dissimilar oxides create a unique platform that only requires 1.52 and 1.72 V to achieve current densities of 100 and 500 mA cm−2, respectively, in alkaline seawater. MO@FO displayed anti-corrosive behavior as it possesses a low corrosion current of 9 nA cm−2 and a corrosion rate of only 0.036 μm per year. It inhibits chlorine evolution reaction and hypochlorite generation, confirmed by GC-MS and DPD tests, hence remained stable for over 1000 h. The DFT calculations show that MoO2 is the active centers in the heterostructure while addition of polyanions assists in the formation of a protective layer on the catalyst surface, providing additional protection against chloride ions. Hence, this study presents an effective and efficient strategy for stable anodic reactions in alkaline seawater for hydrogen production. [ABSTRACT FROM AUTHOR]

To determine the possible role of matrix metallopeptidase (MMP)-8 and MMP-9 in the development of chronic subdural hematoma (CSDH), we investigated their expression in CSDH. In our previous study, we analyzed hematoma fluid and peripheral blood of 83 patients with CSDH, including 17 postoperative patients. Based on these results, we included 50 people in the normal group and analyzed 20 markers in the peripheral blood of each person. In order to identify representative markers, it was assessed by using overall differential gene expression. The concentration of MMP-8 was significantly higher in the normal group than that in the preoperative and postoperative groups. The concentration of MMP-9 was significantly lower in the normal group than in both preoperative and postoperative groups. Immunohistochemistry confirmed the expression of MMP-8 and MMP-9 in CSDH membranes. In conclusion, our results provide evidence of the expression of MMP-8 and MMP-9 in CSDH. In addition, the expression of MMP-8 and MMP-9 suggests angiogenesis in CSDH formation.

Abstract Rough Li plating, low ionic conductivity, and low thermal stability of conventional electrolytes post‐primary challenges for achieving reliable high‐capacity rechargeable lithium batteries, for which lithium metal is frequently proposed as the most promising anode material. Conventional low‐polarity commercial polypropylene/polyethylene separators fail to support the application of high‐energy‐density Li anodes due to their rigid physicochemical properties and the high reactivity of Li metal, leading to fatal dendrite formation and vigorous exothermic reaction with electrolytes. Herein, we develop a Li‐wetting, flame‐retardant binary polymer electrolyte by functionalizing poly(vinylidene fluoride) (PVDF) separators with nonflammable polybenzimidazole (PBI) to build safe room‐temperature solid‐state electrolyte membranes. A dendrite‐free LiFePO4 cell with the solid polymer electrolyte (SPE) delivers a discharge capacity of 127 mAh g−1 at 25°C with a capacity retention of 87.5% after 500 cycles at 0.5°C (0.15 mA cm−2). Phase‐field simulations and density functional theory calculations demonstrate that the negatively charged benzimidazole chains of PBI own superior affinity to lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and shares overlapping electron density with Li anode, giving rise to accelerated Li+ conduction at room temperature and uniform Li electrodeposition at the electrolyte/Li metal interface. The SPE is also flame‐retardant since heat‐resistant polytetrafluoroethylene and a dense, heat‐blocking graphitized carbon layer are formed in intense heat through dehydrogenation/fluorination of PVDF under the catalysis of Lewis base imidazole rings and the decomposition of benzimidazole rings in PBI. No such fire‐resistant mechanism is ever reported in conventional electrolytes.