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OBJECTIVE: To evaluate the long-term outcomes of subtotal hemispherotomy (SH) in treating drug-resistant epilepsy caused by unilateral hemispheric lesions and try to give the prognostic factors for these outcomes. METHODS: We retrospectively reviewed the clinical data of 19 patients who underwent SH in Sanbo Brain Hospital, Capital Medical University, Beijing, China, from May 2008 to April 2021. All clinical data and factors related to surgical and functional outcomes, including motor, neuropsychiatric, and language function, were collected and analyzed. RESULTS: The surgical outcomes showed 13 (68â¯%) patients were seizure-free at the last follow-up (2-14 years, mean: 5.6±2.9). No changes were found in motor outcomes in 12 (63â¯%) patients; seven (37â¯%) patients had new permanent motor deficits (NPMD). Improvement in the full-scale intelligence quotient (FIQ) (p = 0.009) was observed. Univariate analysis found that patients who did not achieve seizure freedom had a significantly older age at surgery (p = 0.017) and acute post-operative seizures (APOS) (p = 0.046). Kaplan-Meier analysis also identified significant differences in seizure outcomes between the children and adult subgroups (p = 0.0017). Multivariate Cox analysis showed that older age at surgery (HR=1.055, p = 0.034) was associated with shorter time-to-seizure-recurrence. Resection of the central operculum and insula (OR= 80.433, p =0.031) and higher monthly seizure frequency (OR= 1.073, p = 0.040) were also poor prognostic factors for motor function outcomes. CONCLUSION: SH is an effective treatment procedure in treating patients with drug-resistant epilepsy caused by hemispheric lesions with satisfied seizure outcomes, limited impairment of motor function, and preserving neuropsychiatric outcomes.
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Unlike many studies that regulate transport and separation behaviour of photogenerated charge carriers through controlling the chemical composite, our work demonstrates this goal can be achieved through simply tuning the molecular π-π packing from short-range to long-range within hydrogen-bonded organic frameworks (HOFs) without altering the building blocks or network topology. Further investigations reveal that the long-range π-π stacking significantly promotes electron delocalization and enhances electron density, thereby effectively suppressing electron-hole recombination and augmenting the charge transfer rate. Simultaneously, acting as a porous substrate, it boosts electron density of Pd nanoparticle loaded on its surfaces, resulting in remarkable CO2 photoreduction catalytic activity (CO generation rate: 48.1 µmol/g/h) without the need for hole scavengers. Our study provide insight into regulating the charge carrier behaviours in molecular assemblies based on hydrogen bonds, offering a new clue for efficient photocatalyst design.
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OBJECTIVE: To summarize the surgical outcomes of genetically refractory epilepsy and identify prognostic factors for these outcomes. METHODS: A literature search of the PubMed, Web of Science, and Embase databases for relevant studies, published between January 1, 2002 and December 31, 2023, was performed using specific search terms. All studies addressing surgical outcomes and follow-up of genetically refractory epilepsy were included. All statistical analyses were performed using STATA software (StataCorp LLC, College Station, TX, USA). This review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, 2020 (i.e., "PRISMA") reporting guidelines. RESULTS: Of the 3833 studies retrieved, 55 fulfilled the inclusion criteria. Eight studies were eligible for meta-analysis at the study level. Pooled outcomes revealed that 74 % of patients who underwent resective surgery (95 % confidence interval [CI] 0.55-0.89; z = 9.47, p < 0.05) achieved Engel I status at the last follow-up. In the study level analysis, pooled outcomes revealed that 9 % of patients who underwent vagus nerve stimulation achieved seizure-free status (95 % CI 0.00-0.31; z = 1.74, p < 0.05), and 61 % (95 % CI 0.55-0.89; z = 11.96, p < 0.05) achieved a 50 % reduction in seizure frequency at the last follow-up. Fifty-three studies comprising 249 patients were included in an individual-level analysis. Among patients who underwent lesion resection or lobectomy/multilobar resection, 65 % (100/153) achieved Engel I status at the last follow-up. Univariate analysis indicated that female sex, somatic mutations, and presenting with focal seizure symptoms were associated with better prognosis (p < 0.05). Additionally, 75 % (21/28) of patients who underwent hemispherectomy/hemispherotomy achieved Engel I status at the last follow-up. In the individual-level analysis, among patients treated with vagus nerve stimulation, 21 % (10/47) were seizure-free and 64 % (30/47) experienced >50 % reduction in seizure frequency compared with baseline. CONCLUSION: Meticulous presurgical evaluation and selection of appropriate surgical procedures can, to a certain extent, effectively control seizures. Therefore, various surgical procedures should be considered when treating patients with genetically refractory epilepsy.
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Epilepsia Refractaria , Humanos , Epilepsia Refractaria/cirugía , Epilepsia Refractaria/genética , Resultado del Tratamiento , Procedimientos Neuroquirúrgicos , Estimulación del Nervio VagoRESUMEN
The conversion of CO2 to C2 through photocatalysis poses significant challenges, and one of the biggest hurdles stems from the sluggishness of the multi-electron transfer process. Herein, taking metal-organic framework (PFC-98) as a model photocatalyst, we report a new strategy to facilitate charge separation. This strategy involves matching the energy levels of the lowest unoccupied node and linker orbitals of the MOF, thereby creating the lowest unoccupied crystal orbital (LUCO) delocalized over both the node and linker. This feature enables the direct excitation of electrons from photosensitive linker to the catalytic centers, achieving a direct charge transfer (DCT) pathway. For comparison, an isoreticular MOF (PFC-6) based on analogue components but with far apart frontier energy level was synthesized. The delocalized LUCO caused the presence of an internal charge-separated state (ICS), prolonging the excited state lifetime and further inhibiting the electron-hole recombination. The presence of an internal charge-separated state (ICS) prolongs the excited state lifetime and further inhibits the electron-hole recombination. Moreover, it also induced abundant electrons accumulating at the catalytic sites, enabling the multi-electron transfer process. As a result, the material featuring delocalized LUCO exhibits superior overall CO2 photocatalytic performance with high C2 production yield and selectivity.
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INTRODUCTION: The overall reject rate (RR) of our newly set up Radiology department was an average of 14%, higher than the recommended 8% target and 10% threshold set by the American Association of Physicists in Medicine (AAPM). An analysis done to identify potential causes of a high RR suggested that radiographers might have been rejecting images of diagnostic value. A lack of consistency in the definition of a diagnostic value image amongst radiographers may be a possible cause in the higher overall RR. This study aims to investigate potential discrepancies among radiographers in defining a diagnostic radiograph. METHODS: An online survey composed of an image bank with a questionnaire was created, participants grade each image as either accepted or rejected. Fleiss Kappa was used to determine the level of agreement between the radiographers in accepting or rejecting the images in the image bank. RESULTS: Twenty radiographers with varying years of experience participated in this study. There was fair agreement amongst the radiographers' judgements, k=.277 (95% CI, .277 to .278), p < .005. Individual kappa for the "Accept" and "Reject" categories were both 0.277. There is no significant difference in the agreement level across the junior (k=.278), intermediate (k=.371) and senior (k=.275) radiographers. CONCLUSION: The result suggests that there is discrepancy in the radiographers' definition of a diagnostic radiograph and this misalignment of radiographers' perception might be one of the underlying causes of high RR. IMPLICATIONS FOR PRACTICE: This study has provided the researchers with a better insight on the underlying cause of the department high RR. By calibrating the radiographers' definition of a diagnostic radiograph, it will help realign the radiographer's agreement on when a radiograph should be rejected. This will reduce the overall RR and patient's overall dose. A lower RR translates to a more efficient turnaround time in General Radiography services, ensuring quality service is provided without further strain on our limited resources.
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Colorectal cancer (CRC) is the third most common cancer worldwide and the second most common cause of cancer death. Nanotherapies are able to selectively target the delivery of cancer therapeutics, thus improving overall antitumor efficiency and reducing conventional chemotherapy side effects. Mesoporous silica nanoparticles (MSNs) have attracted the attention of many researchers due to their remarkable advantages and biosafety. We offer insights into the recent advances of MSNs in CRC treatment and their potential clinical application value.
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While the construction of a donor-acceptor (D-A) structure has gained great attention across various scientific disciplines, such structures are seldomly reported within the field of hydrogen-bonded organic frameworks (HOFs). Herein, a D-A based HOF is synthesized, where the adjacent D-A pairs are connected by hydrogen bonds instead of the conventionally employed covalent bonds. This structural feature imparts material with a reduced energy gap between excited state and triplet state, thereby facilitating the intersystem crossing (ISC) and boosting the generation rate of single oxygen (quantum yield = 0.98). Consequently, the resulting material shows high performance for antimicrobial photodynamic therapy (PDT). The impact of D-A moiety is evident when comparing this finding to a parallel study conducted on an isoreticular HOF without a D-A structure. The study presented here provides in-depth insights into the photophysical properties of D-A pair in a hydrogen-bonded network, opening a new avenue to the design of innovative materials for efficient PDT.
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BACKGROUND: An urgent need exists for innovative surgical video recording techniques in head and neck reconstructive surgeries, particularly in low- and middle-income countries where a surge in surgical procedures necessitates more skilled surgeons. This demand, significantly intensified by the COVID-19 pandemic, highlights the critical role of surgical videos in medical education. We aimed to identify a straightforward, high-quality approach to recording surgical videos at a low economic cost in the operating room, thereby contributing to enhanced patient care. METHODS: The recording was comprised of six head and neck flap harvesting surgeries using GoPro or two types of digital cameras. Data were extracted from the recorded videos and their subsequent editing process. Some of the participants were subsequently interviewed. RESULTS: Both cameras, set at 4 K resolution and 30 frames per second (fps), produced satisfactory results. The GoPro, worn on the surgeon's head, moves in sync with the surgeon, offering a unique first-person perspective of the operation without needing an additional assistant. Though cost-effective and efficient, it lacks a zoom feature essential for close-up views. In contrast, while requiring occasional repositioning, the digital camera captures finer anatomical details due to its superior image quality and zoom capabilities. CONCLUSION: Merging these two systems could significantly advance the field of surgical video recording. This innovation holds promise for enhancing technical communication and bolstering video-based medical education, potentially addressing the global shortage of specialized surgeons.
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COVID-19 , Grabación en Video , Humanos , COVID-19/epidemiología , Procedimientos de Cirugía Plástica/educación , Colgajos Quirúrgicos , SARS-CoV-2 , Cabeza/cirugía , Cuello/cirugíaRESUMEN
The traditional lecture-based learning (LBL) method is facing great challenges due to its low efficiency and single proceeding form. We designed a PRI-E learning mode that combined and modified problem-based, case-based, and evidence-based learning with a step-by-step approach. We evaluated the practical learning outcomes of using the PRI-E mode by comparing it with traditional lecture-based learning in oral and maxillofacial oncology education. "PRI-E" consists of the first letters of the English words Passion, Research, Innovation, and Education, and it means "the best Education". This prospective randomized controlled trial included 40 participants. We evenly divided the participants into the PRI-E (n = 20) and LBL group (n = 20) based on the entrance test scores. The same staff group designed and then taught the learning content with different group measures. The evaluation included the final test scores and questionnaire assessments. Without affecting the examination results, the PRI-E teaching method was more satisfactory and popular with participants in terms of ability development and classroom participation. Enacting the PRI-E teaching method required more time, but this did not affect its popularity among the participants. Compared with the LBL learning mode, the PRI-E learning mode was more organized and efficient in oral and maxillofacial oncology education without affecting academic performance. This model has a high degree of satisfaction, which is conducive to training students' comprehensive ability.
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Aprendizaje , Aprendizaje Basado en Problemas , Humanos , Aprendizaje Basado en Problemas/métodos , Estudios Prospectivos , Estudiantes , Evaluación EducacionalRESUMEN
The vortex flowmeter occupies a vital position in flow measurement with its unique advantages. It is essentially a fluid vibration instrument, and its measurement process is susceptible to interference, which seriously affects measurement accuracy. In particular, at low flow rates, it is an urgent problem to extract vortex signals from the complex noise. Among many signal processing methods, Empirical Mode Decomposition (EMD) is a time-frequency analysis method suitable for nonlinear, non-stationary signals. EMD can adaptively decompose noisy signals into noise and useful signal components arranged from high frequency to low frequency. For the above problems, an innovative, improved EMD method is proposed in this paper. The digital filter is designed according to the amplitude-frequency characteristic of vortex signals. After filtering, the vortex signal is adjusted to a fixed value, and high-frequency noise is filtered. According to the consistency of the filtered signal's amplitude, we design a decomposition stop criterion for EMD to process the output signal of the vortex sensor. This method not only maintains the characteristic of adaptive decomposition in EMD but also completes the automatic extraction of the vortex signal under complex noise. It provides a new comprehensive method for realizing high-precision and anti-interference vortex flowmeters.
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MOF-808, owing to the synergistic effect of its large surface area and surface charge matching, showed a diclofenac sodium (DCF) removal capacity as high as 630 mg g-1, and the ability to adsorb 436 mg g-1 DCF in two hours, outperforming many common Zr-MOFs under the same conditions. Importantly, a series of free-standing mixed-matrix membranes made by combining polyacrylonitrile with MOF-808 were fabricated and exhibited high efficiency of removing DCF from water via an easily accessible filtration method.
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Achieving active site engineering at the atomic level poses a significant challenge in the design and optimization of catalysts for energy-efficient catalytic processes, especially for a reaction with two reactants competitively absorbed on catalytic active sites. Herein, we show an example that tailoring the local environment of cobalt sites in a robust metal-organic framework through substituting the bridging atom from -Cl to -OH group leads to a highly active catalyst for oxygen activation in an oxidation reaction. Comprehensive characterizations reveal that this variation imparts drastic changes on the electronic structure of metal centers, the competitive reactant adsorption behavior, and the intermediate formation. As a result, exceptional low-temperature CO oxidation performance was achieved with T25(Temperature for 25 % conversion)=35 °C and T100 (Temperature for 100 % conversion)=150 °C, which stands out from existing MOF-based catalysts and even rivals many noble metal catalysts. This work provides a guidance for the rational design of catalysts for efficient oxygen activation for an oxidation reaction.
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BACKGROUND: Phospholipase A2 (PLA2) enzymes are pivotal in various biological processes, such as lipid mediator production, membrane remodeling, bioenergetics, and maintaining the body surface barrier. Notably, these enzymes play a significant role in the development of diverse tumors. AIM: To systematically and comprehensively explore the expression of the PLA2 family genes and their potential implications in cholangiocarcinoma (CCA). METHODS: We conducted an analysis of five CCA datasets from The Cancer Genome Atlas and the Gene Expression Omnibus. The study identified differentially expressed genes between tumor tissues and adjacent normal tissues, with a focus on PLA2G2A and PLA2G12B. Gene Set Enrichment Analysis was utilized to pinpoint associated pathways. Moreover, relevant hub genes and microRNAs for PLA2G2A and PLA2G12B were predicted, and their correlation with the prognosis of CCA was evaluated. RESULTS: PLA2G2A and PLA2G12B were discerned as differentially expressed in CCA, manifesting significant variations in expression levels in urine and serum between CCA patients and healthy individuals. Elevated expression of PLA2G2A was correlated with poorer overall survival in CCA patients. Additionally, the study delineated pathways and miRNAs associated with these genes. CONCLUSION: Our findings suggest that PLA2G2A and PLA2G12B may serve as novel potential diagnostic and prognostic markers for CCA. The increased levels of these genes in biological fluids could be employed as non-invasive markers for CCA, and their expression levels are indicative of prognosis, underscoring their potential utility in clinical settings.
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Intrahepatic cholestasis of pregnancy (ICP) is associated with an increased risk of cesarean section and adverse fetal outcomes. Currently, ICP diagnosis depends largely on serum levels of bile acids and lacks sensitivity and specificity for accurate diagnosis. Tongue diagnosis is an important diagnostic tool in traditional Chinese medicine (TCM) and is used in our clinic as complementary treatment and personalized medicine for ICP. However, the molecular basis of the manifestation of greasy white tongue coatings in ICP remains unknown. In this study, we performed untargeted metabolomic profiling of the serum, tongue coating, and saliva of 66 pregnant women, including 22 with ICP. The metabolomic profiles of the serum and tongue coatings showed marked differences between the two clinical groups. Forty-six differentially abundant metabolites were identified, and their relative concentrations correlated with total bile acid levels. These differential metabolites included bile acids, lipids, microbiota- and diet-related metabolites, and exposomes. Conventional biochemical markers, including serum aminotransferases and bilirubin, were not significantly increased in the ICP group, whereas the total cholesterol and triglyceride levels were significantly increased as early as the first trimester. Our data provide insights into the pathophysiology of ICP and implicate the gut-liver axis and environmental exposure. Tongue coating has the potential to be a non-invasive diagnostic approach. Further studies are required to validate the clinical utility of these findings.
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Colestasis Intrahepática , Complicaciones del Embarazo , Embarazo , Femenino , Humanos , Mujeres Embarazadas , Cesárea , Ácidos y Sales Biliares , Complicaciones del Embarazo/diagnóstico , Colestasis Intrahepática/diagnóstico , LenguaRESUMEN
BACKGROUND: Postoperative ileus (POI) is a common obstruction of intestinal content passage caused by almost all abdominal operations that seriously strokes the quality of life of patients. Kuanchang-Shu granule (KCSG), a classic modified prescription based on "Da-Cheng-Qi Decoction", has obtained satisfactory efficacy in the clinical therapeutics of POI. However, its material basis and holistic molecular mechanism against POI have not been revealed. METHODS: The chemical ingredients of KCSG were first characterized by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS). Subsequently, an integration strategy of the network pharmacology and molecular docking based on above identified ingredients was performed to unveil the potential targets involved in the treatment of KCSG on POI. Finally, intestinal manipulation induced rat POI model was constructed to verify the efficacy and predicted mechanism of KCSG against POI. RESULTS: In total, 246 ingredients mainly including organic acids, flavonoids, quinones, alkaloids, terpenoids, phenylpropanoids and phenols were identified. 41 essential ingredients, 24 crucial targets as well as 15 relevant signaling pathways were acquired based on network pharmacology analysis. Pharmacodynamic research showed that KCSG treatment could protect intestinal histological damage, promote the recovery of measurement of gastrointestinal transit disorder and inhibit the secretion of myeloperoxidase in the distal ileum tissues. The up-regulated expression of p-AKT and down-regulated expression of p-eNOS and HSP9OAA1 predicted by molecular docking and validated by western blotting showed that AKT/eNOS/HSP90AA1 pathway may be one of the crucial mechanisms that mediates the protective effect of KCSG.
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Hydrogen-Bonded organic frameworks (HOFs) are a type of emerging porous materials. At present, little research has been conducted on their solution state. This work demonstrates that HOFs fragment into small particles while maintaining their original assemblies upon dispersing in solvents, as confirmed by Cryo-electron microscopy coupled with 3D electron diffraction technology. 1D and 2D-Nuclear Magnetic Resonance (NMR) and zeta potential analyses indicate the HOF-based colloid solution and the isolated molecular solution have significant differences in intermolecular interactions and aggregation behavior. Such unique solution processibility allows for fabricating diverse continuous HOF membranes with high crystallinity and porosity through solution-casting approach on various substrates. Among them, HOF-BTB@AAO membranes show high C3H6 permeance (1.979 × 10-7 mol·s-1·m-2·Pa-1) and excellent separation performance toward C3H6 and C3H8 (SF = 14). This continuous membrane presents a green, low-cost, and efficient separation technology with potential applications in petroleum cracking and purification.
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Neuroinflammation is associated with poor outcomes in patients with spinal cord injury (SCI). Recent studies have demonstrated that stimulator of interferon genes (Sting) plays a key role in inflammatory diseases. However, the role of Sting in SCI remains unclear. In the present study, it is found that increased Sting expression is mainly derived from activated microglia after SCI. Interestingly, knockout of Sting in microglia can improve the recovery of neurological function after SCI. Microglial Sting knockout restrains the polarization of microglia toward the M1 phenotype and alleviates neuronal death. Furthermore, it is found that the downregulation of mitofusin 2 (Mfn2) expression in microglial cells leads to an imbalance in mitochondrial fusion and division, inducing the release of mitochondrial DNA (mtDNA), which mediates the activation of the cGas-Sting signaling pathway and aggravates inflammatory response damage after SCI. A biomimetic microglial nanoparticle strategy to deliver MASM7 (named MSNs-MASM7@MI) is established. In vitro, MSNs-MASM7@MI showed no biological toxicity and effectively delivered MASM7. In vivo, MSNs-MASM7@MI improves nerve function after SCI. The study provides evidence that cGas-Sting signaling senses Mfn2-dependent mtDNA release and that its activation may play a key role in SCI. These findings provide new perspectives and potential therapeutic targets for SCI treatment.
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Microglía , Traumatismos de la Médula Espinal , Humanos , Microglía/metabolismo , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Regulación hacia Abajo , Inflamación/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Nucleotidiltransferasas/metabolismoRESUMEN
STUDY DESIGN: Retrospective Study. OBJECTIVE: This study aims to investigate variation in the number of thoracic and lumbar vertebrae, the prevalence of lumbosacral transitional vertebra (LSTV) and the prevalence of cervical ribs among surgical patients with adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: Due to variation in the number of thoracic or lumbar vertebrae, inaccurate identification of vertebral levels has been found to be a contributory factor to wrong-level surgery. METHODS: This was a retrospective study on AIS patients who underwent posterior spinal fusion. Demographic and anthropometric data (age, gender, height, weight, and body mass index), radiographic data (Lenke curve type, pre-operative Cobb angle, vertebra numbering of cervical, thoracic, and lumbar spine, presence of LSTV based on the Castellvi classification and the presence of cervical ribs) and clinical data were collected. Data were analysed and reported with mean and standard deviation for quantitative parameters and number and percentage for qualitative parameters. Multinomial logistic regression analyses were performed to identify factors associated with the outcomes of interest. RESULTS: A total of 998 patients met inclusion criteria, of which 135 (13.5%) were males and 863 (86.5%) were females. The vertebrae number varied between 23 to 25 total vertebrae with 24 vertebrae considered as the typical number of vertebrae. The prevalence of atypical number of vertebrae (23 or 25) was 9.8% (98 patients). We found a total of 7 different variations in number of cervical, thoracic, and lumbar vertebrae (7C11T5L, 7C12T4L, 7C11T6L, 7C12T5L, 7C13T4L, 7C12T6L, and 7C13T5L) with 7C12T5L considered as the typical vertebrae variation. The total prevalence of patients with atypical vertebrae variation was 15.5% (155 patients). Cervical ribs were found in 2 (0.2%) patients while LSTV were found in 250 (25.1%) of patients. The odds of 13 thoracic vertebrae were higher in males (OR 5.17; 95% CI: 1.25, 21.39) and the odds of 6 lumbar vertebrae were higher in LSTV (OR 3.93; 95% CI: 2.58, 6.00). CONCLUSION: In this series, we identified a total of 7 different variations in the number of cervical, thoracic, and lumbar vertebrae. The total prevalence of patients with atypical vertebrae variation was 15.5%. LSTV was found in 25.1% of the cohort. It is important to ascertain atypical vertebrae variations rather than the absolute number of vertebrae because variants such as 7C11T6L and 7C13T4L may still have typical numbers of vertebrae in total. However, due to the differences in the number of morphologically thoracic and lumbar vetrebrae, there may still be a risk of inaccurate identification.
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Costilla Cervical , Cifosis , Anomalías Musculoesqueléticas , Escoliosis , Fusión Vertebral , Masculino , Femenino , Humanos , Adolescente , Escoliosis/diagnóstico por imagen , Escoliosis/epidemiología , Escoliosis/cirugía , Estudios Retrospectivos , Prevalencia , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Vértebras Torácicas/cirugía , Resultado del TratamientoRESUMEN
Etomidate (ETO) is a highly-efficient drug that can induce anesthesia with increasing doses, thus subject to strict regulation. However, an accurate and efficient method for ETO intake detection is currently lacking. Therefore, this study developed a straightforward sample preparation method using LC-MS/MS to analyze ETO and its primary metabolite, etomidate acid (ETA), in urine, liver, and kidney samples. Snap frozen pig liver and kidney samples were ground into a fine powder. Then, all the biological samples, including human urine, pig liver and kidney tissues, were deproteinized using acetonitrile and filtered for analysis. The separation was achieved in 9.01 min with gradient elution. The calibration curves ranged from 0.5 to 50 ng/mL for ETO in urine and 0.5 to 50 ng/g in liver and kidney, while the curves ranged from 1 to 100 ng/mL for ETA in urine and 1 to 100 ng/g in liver and kidney. The correlation coefficients (R2) were greater than 0.9957. The Limit of detection (LOD) and limit of quantitation (LOQ) for ETO were 0.2 and 0.5 ng/mL in urine samples and 0.2 and 0.5 ng/g in liver and kidney samples, respectively. For ETA, the LOD and LOQ were 0.5 and 1 ng/mL in urine samples and 0.5 and 1 ng/g in liver and kidney samples. This method was assessed by validation parameters, including selectivity, intra- and inter-day precision and accuracy, recovery, matrix effect, dilution integrity and stability. It was successfully applied to a practical case, revealing ETO and ETA concentrations in urine of 1.01 and 5.58 µg/mL, in liver samples of 12.30 and 1.13 µg/g, and in kidney samples of 6.95 and 4.23 µg/g. This suggests that the method is suitable for routine forensic detection of illicit ETO abuse.
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Etomidato , Humanos , Animales , Porcinos , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Líquida con Espectrometría de Masas , Hígado , Riñón , Reproducibilidad de los ResultadosRESUMEN
Copper (Cu), with the advantage of producing a deep reduction product, is a unique catalyst for the electrochemical reduction of CO2 (CO2RR). Designing a Cu-based catalyst to trigger CO2RR to a multicarbon product and understanding the accurate structure-activity relationship for elucidating reaction mechanisms still remain a challenge. Herein, we demonstrate a rational design of a core-shell structured silica-copper catalyst (p-Cu@m-SiO2) through Cu-Si direct bonding for efficient and selective CO2RR. The Cu-Si interface fulfills the inversion in CO2RR product selectivity. The product ratio of C2H4/CH4 changes from 0.6 to 14.4 after silica modification, and the current density reaches a high of up to 450 mA cm-2. The kinetic isotopic effect, in situ attenuated total reflection Fourier-transform infrared spectra, and density functional theory were applied to elucidate the reaction mechanism. The SiO2 shell stabilizes the *H intermediate by forming Si-O-H and inhibits the hydrogen evolution reaction effectively. Moreover, the direct-bonded Cu-Si interface makes bare Cu sites with larger charge density. Such bare Cu sites and Si-O-H sites stabilized the *CHO and activated the *CO, promoting the coupling of *CHO and *CO intermediates to form C2H4. This work provides a promising strategy for designing Cu-based catalysts with high C2H4 catalytic activity.