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Serious haze pollution, mainly caused by fine and ultrafine particulate matters (PMs) and aerosols, poses a significant threat to the public health, especially when the aerodynamic diameter is less than 2.5 µm. Electrostatic capture techniques, such as polymer electret filters and kinetic plasma processes, are widely used instead of mechanical filtration with high removal efficiency and low wind resistance (pressure drop). However, the inability to recharge, coupled with the generation of ozone byproducts, makes it challenging to meet the requirements for both recoverability and highly efficient filtration. Here, we propose an electrostatic filter as an alternative to conventional polymer electrets, aiming to achieve an ultrahigh removal efficiency, long-term performance stability, and reusability. Piezoelectric LiNbO3 (LN) particles are integrated into the polypropylene (PP) matrix through the melt-blown strategy to fabricate the LN/PP nonwoven fabric. Benefiting from the employment of piezoelectric LN particles, the LN/PP nonwovens exhibit an ultrahigh removal efficiency of 99.9% for PM0.3 to PM10. The airflow facilitates the sustained regeneration of piezoelectric charges on the surface of LN/PP nonwovens, thereby maintaining a removal efficiency of approximately 95% for continuous filtration over 11 days. Even after eight cycles of washing, the removal efficiency of the LN/PP nonwovens remains at nearly 90%, demonstrating the excellent reusability. Our proposed strategy offers an ingenious combination of high-efficiency and recoverability for filters, holding great promise for reducing plastic pollution.
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PURPOSE: To evaluate the role of intraoperative frozen biopsy of central lymph nodes in central neck dissection and thyroidectomy in patients of unilateral, clinically negative nodes (cN0) papillary thyroid microcarcinoma (PTMC) without extra-glandular invasion. METHODS: The clinical data of 465 patients were collected retrospectively. Part of prelaryngeal, pretracheal and ipsilateral paratracheal lymph nodes were taken for frozen pathological examination during the operation. Then the thyroid lobe on the tumor side and isthmus were excised, and central neck dissection of the affected side was performed in all patients. The number of metastases in entire central lymph nodes of the affected side can be obtained by postoperative paraffin pathology. If the number of positive lymph nodes during surgery is ≥3, contralateral gland resection was performed. RESULTS: In this group of 465 patients, there were 186 cases with central lymph node metastasis. The Kappa coefficient of consistency between frozen pathology and paraffin pathology in central lymph nodes was 0.605. The ROC curve for the number of intraoperative frozen metastases-postoperative pathological metastases over 5 showed that the AUC of the curve was 0.793, while the maximum Youden index was 0.5259, whose corresponding number of positive lymph nodes was 3. CONCLUSION: Intraoperative central lymph nodes biopsy can be used as an important indicator for the status of central lymph node metastasis in unilateral cN0 PTMC patients without extra-glandular invasion and a determinant for central lymph node dissection. While the number of positive lymph nodes intraoperatively is ≥3, total thyroidectomy should be considered.
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Carcinoma Papilar , Ganglios Linfáticos , Metástasis Linfática , Neoplasias de la Tiroides , Tiroidectomía , Humanos , Masculino , Femenino , Adulto , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugía , Persona de Mediana Edad , Estudios Retrospectivos , Metástasis Linfática/patología , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Carcinoma Papilar/cirugía , Carcinoma Papilar/patología , Disección del Cuello , Anciano , Biopsia , Adulto JovenRESUMEN
BACKGROUND: The purpose of this study is to evaluate the effects of neoadjuvant therapy on glucose and lipid metabolism, bone mineral density (BMD) and muscle, and to explore the relationship between metabolic disorders and changes in body composition, so as to provide better health management strategies for breast cancer survivors. METHODS: The clinical data of 43 patients with breast cancer who received neoadjuvant therapy in Xuanwu Hospital from January 2020 to June 2021 were analyzed retrospectively. The biochemical results, including albumin, blood glucose, triglyceride and cholesterol, were collected before neoadjuvant therapy and before surgery. The pectoral muscle area, pectoral muscle density and cancellous bone mineral density of the 12th thoracic vertebra were also measured by chest CT. RESULTS: After neoadjuvant therapy, fasting blood glucose, triglyceride and cholesterol were significantly increased, albumin was decreased. At the same time, pectoral muscle area, pectoral muscle density and T12 BMD were decreased. After treatment, BMD was positively correlated with pectoral muscle area, R2 = 0.319, P = 0.037, and BMD was also positively correlated with pectoral muscle density, R2 = 0.329, P = 0.031. Multivariate analysis showed that BMD and pectoral muscle density were correlated with menstrual status, and pectoral muscle area was correlated with body mass index before treatment, none of which was related to glucose and lipid metabolism. CONCLUSION: Neoadjuvant therapy can cause glucose and lipid metabolism disorder, BMD decrease and muscle reduction. BMD was positively correlated with muscle area and density after treatment, suggesting that patients had an increased chance of developing osteosarcopenia.
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Densidad Ósea , Neoplasias de la Mama , Terapia Neoadyuvante , Sarcopenia , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Terapia Neoadyuvante/efectos adversos , Persona de Mediana Edad , Sarcopenia/etiología , Sarcopenia/diagnóstico por imagen , Estudios Retrospectivos , Adulto , Densidad Ósea/efectos de los fármacos , Enfermedades Metabólicas/etiología , Anciano , Composición Corporal , Factores de RiesgoRESUMEN
Paddy fields are hotspots of microbial denitrification, which is typically linked to the oxidation of electron donors such as methane (CH4) under anoxic and hypoxic conditions. While several anaerobic methanotrophs can facilitate denitrification intracellularly, whether and how aerobic CH4 oxidation couples with denitrification in hypoxic paddy fields remains virtually unknown. Here we combine a ~3300 km field study across main rice-producing areas of China and 13CH4-DNA-stable isotope probing (SIP) experiments to investigate the role of soil aerobic CH4 oxidation in supporting denitrification. Our results reveal positive relationships between CH4 oxidation and denitrification activities and genes across various climatic regions. Microcosm experiments confirm that CH4 and methanotroph addition promote gene expression involved in denitrification and increase nitrous oxide emissions. Moreover, 13CH4-DNA-SIP analyses identify over 70 phylotypes harboring genes associated with denitrification and assimilating 13C, which are mostly belonged to Rubrivivax, Magnetospirillum, and Bradyrhizobium. Combined analyses of 13C-metagenome-assembled genomes and 13C-metabolomics highlight the importance of intermediates such as acetate, propionate and lactate, released during aerobic CH4 oxidation, for the coupling of CH4 oxidation with denitrification. Our work identifies key microbial taxa and pathways driving coupled aerobic CH4 oxidation and denitrification, with important implications for nitrogen management and greenhouse gas regulation in agroecosystems.
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Desnitrificación , Metano , Oryza , Oxidación-Reducción , Microbiología del Suelo , Suelo , Metano/metabolismo , Oryza/metabolismo , Oryza/microbiología , China , Suelo/química , Aerobiosis , Bacterias/metabolismo , Bacterias/genética , Bacterias/clasificación , Óxido Nitroso/metabolismo , Filogenia , Isótopos de Carbono/metabolismo , MetagenomaRESUMEN
The models used to describe the light response of electron transport rate in photosynthesis play a crucial role in determining two key parameters i.e., the maximum electron transport rate (J max) and the saturation light intensity (I sat). However, not all models accurately fit J-I curves, and determine the values of J max and I sat. Here, three models, namely the double exponential (DE) model, the non-rectangular hyperbolic (NRH) model, and a mechanistic model developed by one of the coauthors (Z-P Ye) and his coworkers (referred to as the mechanistic model), were compared in terms of their ability to fit J-I curves and estimate J max and I sat. Here, we apply these three models to a series of previously collected Chl a fluorescence data from seven photosynthetic organisms, grown under different conditions. Our results show that the mechanistic model performed well in describing the J-I curves, regardless of whether photoinhibition/dynamic down-regulation of photosystem II (PSII) occurs. Moreover, both J max and I sat estimated by this model are in very good agreement with the measured data. On the contrary, although the DE model simulates quite well the J-I curve for the species studied, it significantly overestimates both the J max of Amaranthus hypochondriacus and the I sat of Microcystis aeruginosa grown under NH4 +-N supply. More importantly, the light intensity required to achieve the potential maximum of J (J s) estimated by this model exceeds the unexpected high value of 105 µmol photons m-2 s-1 for Triticum aestivum and A. hypochondriacus. The NRH model fails to characterize the J-I curves with dynamic down-regulation/photoinhibition for Abies alba, Oryza sativa and M. aeruginosa. In addition, this model also significantly overestimates the values of J max for T. aestivum at 21% O2 and A. hypochondriacus grown under normal condition, and significantly underestimates the values of J max for M. aeruginosa grown under NO3 -N supply. Our study provides evidence that the 'mechanistic model' is much more suitable than both the DE and NRH models in fitting the J-I curves and in estimating the photosynthetic parameters. This is a powerful tool for studying light harvesting properties and the dynamic down-regulation of PSII/photoinhibition.
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OBJECTIVE: Previous studies have shown that cancer-associated fibroblasts (CAFs) may play a role in tumor growth and development through paracrine action. Several studies reported upregulated matrix metallopeptidase 1 (MMP1) expression in various cancers. The aim is to investigate the role of elevated MMP1 expression in CAFs of breast cancer. METHODS: A total of 203 cases were used for immunohistochemical analysis based on multiple clinical parameters. Tissues for primary cultures of CAFs were collected from 10 breast cancer patients who underwent complete surgical resection of their tumors. MMP1 expression in primary CAFs was detected using reverse transcription-quantitative PCR and western blotting. MMP1-overexpressing CAFs were established via lentiviral transfection, followed by cell functional assays and animal xenograft experiments. RESULTS: MMP1 expression in CAFs of breast cancer was significantly associated with T stage, triple-negative breast cancer status, neoadjuvant chemotherapy status and Ki67 expression. Additionally, MMP1 expression was closely correlated with unfavorable prognosis based on overall survival and disease-free survival analyses. Elevated MMP1 expression in CAFs was verified to promote cell adhesion, invasion, proliferation abilities and attenuate chemosensitivity to Taxotere treatment. CONCLUSION: The results indicated that MMP1 expression in CAFs may participate in the malignant phenotype and unfavorable prognosis of breast cancer.
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Neoplasias de la Mama , Fibroblastos Asociados al Cáncer , Metaloproteinasa 1 de la Matriz , Animales , Femenino , Humanos , Neoplasias de la Mama/patología , Fibroblastos Asociados al Cáncer/metabolismo , Línea Celular Tumoral , Proliferación Celular , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 1 de la Matriz/metabolismo , Pronóstico , Neoplasias de la Mama Triple Negativas/patología , Ratones , Ratones Endogámicos BALB C , Adulto , Persona de Mediana Edad , Células MDA-MB-231RESUMEN
Establishing a multivalent interface between the biointerface of a living system and electronic device is vital to building intelligent bioelectronic systems. How to achieve multivalent binding with spatial tolerance at the nanoscale remains challenging. Here, we report an antibody nanotweezer that is a self-adaptive bivalent nanobody enabling strong and resilient binding between transistor and envelope proteins at biointerfaces. The antibody nanotweezer is constructed by a DNA framework, where the nanoscale patterning of nanobodies along with their local spatial adaptivity enables simultaneous recognition of target epitopes without binding stress. As such, effective binding affinity increases by 1 order of magnitude compared with monovalent antibody. The antibody nanotweezer operating on transistor offers enhanced signal transduction, which is implemented to detect clinical pathogens, showing â¼100% overall agreement with PCR results. This work provides a perspective of engineering multivalent interfaces between biosystems with solid-state devices, holding great potential for organoid intelligence on a chip.
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Anticuerpos de Dominio Único , Epítopos , Transducción de SeñalRESUMEN
BACKGROUND: The incidence of stroke in China ranks first in the world and is the leading cause of death and disability in adults. Urinary incontinence is an independent risk factor leading to poor prognosis of stroke. However, studies on the incidence of urinary incontinence in stroke patients and its influencing factors are different, fluctuate greatly, and there is no unified basis. OBJECTIVE: To quantitatively analyze the incidence of urinary incontinence in stroke patients and its related influencing factors, and further make public health strategic decisions to reduce the occurrence of adverse outcomes. METHODS: Computer searches were conducted in PubMed, Medline, Web of Science, Cochrane Library, Embase, CLNAHL Complete, China National Knowledge Infrastructure (CNKI), Chinese Biomedical database(CBM), Wan Fang Database, VIP Database, observational studies such as cohort studies, case-control studies or cross-sectional studies on the incidence or influencing factors of urinary incontinence in stroke patients from the establishment of the database to the publication in August 2023. Studies selection, quality evaluation and data extraction were conducted independently by two researchers according to the established search strategy. Stata 14.0 statistical software was used for meta-analysis. RESULTS: A total of 21 manuscripts were included, with a cumulative sample size of 7327 cases, including 2887 patients with urinary incontinence. Meta-analysis results showed that the incidence of urinary incontinence in stroke patients was 38% [95% confidence interval (34%, 41%)], including married patients and lacunar infarction were the protective factors for urinary incontinence in stroke patients, while age, chaperone, low educational level, chronic cough, lesion sites (parietal lobe, frontal lobe, and temporal lobe), stroke type (cerebral hemorrhage, subarachnoid hemorrhage and cerebral hemorrhage complicated with subarachnoid hemorrhage), dysfunction (aphasia dyslexia, dysphagia, eye movement abnormalities, leg muscle disorders), post-stroke depression, the higher the NIHSS score, the lower the Bachmann index (BI) score, OCSP classification (total anterior circulation infarction) and other 11 items were risk factors for urinary incontinence in stroke patients. CONCLUSION: The incidence of urinary incontinence in stroke patients is 38%. Marriage and lacunar infarction are the protective factors of urinary incontinence. Age, carer, low educational level, chronic cough, lesion site (parietal, frontal and temporal lobes), stroke type (cerebral hemorrhage, subarachnoid hemorrhage, cerebral hemorrhage combined with subarachnoid hemorrhage), dysfunction (aphasia and dysarthria syndrome, dysphagia, eye movement abnormalities, leg muscle disorders), post-stroke depression, and higher NIHSS score, Lower BI score and OCSP classification (total anterior circulation infarction) were risk factors for urinary incontinence in stroke patients.
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Accidente Cerebrovascular , Incontinencia Urinaria , Humanos , Incontinencia Urinaria/epidemiología , Incontinencia Urinaria/fisiopatología , Incontinencia Urinaria/etiología , Incidencia , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/fisiopatología , China/epidemiologíaRESUMEN
Hematopoietic stem cells (HSCs) represent crucial target cells in the management of hematopoietic and immune system disorders. Unfortunately, the primary source of hematopoietic stem cells is limited. Hematopoietic stem cells derived from induced pluripotent stem cells (iPSCs) hold great promise for applications in cell therapy, disease modeling, and drug screening. To achieve a consistent induction method, one specific induction scheme capable of reliably generating CD34 and CD45 double-positive cells from iPSCs was optimized, employing a comparative analysis and screening of various induction methods. The comprehensive induction procedures are outlined in this document.
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Células Madre Pluripotentes Inducidas , Humanos , Células Madre Hematopoyéticas , Diferenciación Celular , Antígenos CD34RESUMEN
Based on the theory of nitrogen and phosphorus removal and technical requirements, a micro-pressure double-cycle bioreactor coupled with membrane components was used to treat municipal wastewater. The method realized the simultaneous removal of organic matter, nitrogen, and phosphorus in the same reactor and had the characteristics of membrane bioreactor process. Results showed that the average removal efficiency of COD, NH+4-N, TN, and TP were 93.74%, 95.1%, 71.85%, and 81.03%, respectively. During operation, Proteobacteria and Bacteroidetes were the main dominant bacteria, and they had complete nitrogen and phosphorus metabolic pathways. Owing to the low protein content in the mixture, the design of film placement in the micro-precipitation zone was conducive to alleviating the membrane pollution caused by the accumulation of protein, thereby improving the effluent quality and extending the service life of the membrane components.
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Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/métodos , Reactores Biológicos , Nitrógeno , FósforoRESUMEN
PURPOSES: To identify potent DNA methylation candidates that could predict response to temozolomide (TMZ) in glioblastomas (GBMs) that do not have glioma-CpGs island methylator phenotype (G-CIMP) but have an unmethylated promoter of O-6-methylguanine-DNA methyltransferase (unMGMT). METHODS: The discovery-validation approach was planned incorporating a series of G-CIMP-/unMGMT GBM cohorts with DNA methylation microarray data and clinical information, to construct multi-CpG prediction models. Different bioinformatic and experimental analyses were performed for biological exploration. RESULTS: By analyzing discovery sets with radiotherapy (RT) plus TMZ versus RT alone, we identified a panel of 64 TMZ efficacy-related CpGs, from which a 10-CpG risk signature was further constructed. Both the 64-CpG panel and the 10-CpG risk signature were validated showing significant correlations with overall survival of G-CIMP-/unMGMT GBMs when treated with RT/TMZ, rather than RT alone. The 10-CpG risk signature was further observed for aiding TMZ choice by distinguishing differential outcomes to RT/TMZ versus RT within each risk subgroup. Functional studies on GPR81, the gene harboring one of the 10 CpGs, indicated its distinct impacts on TMZ resistance in GBM cells, which may be dependent on the status of MGMT expression. CONCLUSIONS: The 64 TMZ efficacy-related CpGs and in particular the 10-CpG risk signature may serve as promising predictive biomarker candidates for guiding optimal usage of TMZ in G-CIMP-/unMGMT GBMs.
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Neoplasias Encefálicas , Glioblastoma , Glioma , Humanos , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Metilación de ADN , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Temozolomida/farmacología , Temozolomida/uso terapéutico , Glioma/genética , Metilasas de Modificación del ADN/genética , Fenotipo , Antineoplásicos Alquilantes/farmacología , Antineoplásicos Alquilantes/uso terapéutico , Proteínas Supresoras de Tumor/genética , Enzimas Reparadoras del ADN/genéticaRESUMEN
The study proposed a method for determining total nitrogen (TN) content in activated sludge by ultrasound pre-treatment assisted wet method. Based on the single-factor experiment, with the TN content as the response value, the response surface methodology was employed to examine the individual and interactive effects of three factors: the dilution multiple of the sludge mixture, ultrasonic time, and ultrasonic power. At the same time, the physico-chemical parameters and the digestion-oxidation parameters were optimised. The results indicated that the optimal parameters were as follows; sludge dilution multiple of 225 times, stirring rate of 400 r/min, ultrasonic time of 22â minutes, ultrasonic power of 720 W, and optimal added volume of potassium persulfate at 8â mL with a digestion time of 40â minutes. The relative standard deviation (RSD) for the parallel determination of TN in sludge samples using ultrasonic pre-treatment assisted wet method was ≤2.77%, with a spike recovery rate of 98.49-101.43%. The method, ultrasonic pre-treatment assisted wet method to determine TN concentration in activated sludge, was simpler to operate, more accurate.
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Nitrógeno , Aguas del Alcantarillado , Aguas del Alcantarillado/análisis , Aguas del Alcantarillado/química , Nitrógeno/análisis , Eliminación de Residuos Líquidos/métodos , Ultrasonido , Contaminantes Químicos del Agua/análisisRESUMEN
PURPOSE: The high cost of cancer treatment exposes patients to financial toxicity during treatment; however, no study has comprehensively analyzed the incidence of financial toxicity using a validated assessment tool. In this study, the objective was to ascertain the incidence of financial toxicity in cancer patients and the factors influencing it. METHODS: Nine electronic databases were retrieved to collect cross-sectional studies reporting financial toxicity in cancer patients. A random effects meta-analysis was applied to yield the overall prevalence of financial toxicity. Subgroup analyses were conducted depending on the factors affecting financial toxicity. RESULTS: In total, 30 studies met our inclusion criteria. The pooled prevalence of financial toxicity in cancer patients was 48% (95%CI:38%-58%, I2 = 99.4%, p < 0.001). In the subgroup analysis, a higher prevalence of financial toxicity in patients aged <67 years (47%, 95%CI: 28%-66%, I2 = 97.5%, p < 0.001), female (46%, 95%CI:39%-53%, I2 = 94.9%,p < 0.001), lung cancer(57%, 95%CI:38%-75%, I2 = 96.9%, p < 0.001), developing countries (64%, 95%CI:55%-72%, I2 = 98.1%, p < 0.001), time of investigation following COVID-19 (53%, 95%CI:37%-69%, I2 = 99.4%, p < 0.001). CONCLUSION: Financial toxicity is prevalent in cancer patients and is increasingly evident after COVID-19. Furthermore, the odds of financial toxicity are higher in patients who are female, younger, whose cancer type is lung cancer, and from developing countries. These findings emphasize the significance of evaluating financial toxicity in cancer patients after COVID-19, especially in developing countries. This may play a pivotal role in helping patients cope with financial toxicity.
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Neoplasias , Humanos , Neoplasias/economía , Prevalencia , COVID-19/epidemiología , COVID-19/economía , Costo de Enfermedad , Femenino , Estudios Transversales , Masculino , Costos de la Atención en Salud/estadística & datos numéricosRESUMEN
OBJECTIVE: This study aimed to evaluate the improvement of cognitive impairment in older adults through probiotic supplementation. METHODS: A literature review on probiotic supplementation for treating cognitive impairment in older adults was conducted using English and Chinese databases from 1984 to 2023. Two researchers extracted relevant data independently, and a meta-analysis was performed with RevMan software. RESULTS: A comprehensive analysis of ten pertinent papers was conducted, involving a sample of 702 old adults with cognitive impairment. The findings from this study revealed that probiotic supplementation exhibited a positive impact on cognitive symptoms, specifically memory (MD = 0.14, 95% CI :0.05ï½0.22, P = 0.001) and overall cognitive function (SMD = 0.73, 95% CI: 0.25ï½1.21, P=0.003), as well as oxidative stress levels, including total antioxidant capacity (MD=52.54, 95% CI:39.52ï½65.56, P < 0.01), malondialdehyde (MD=-0.11, 95% CI:-0.15ï½-0.07, P < 0.01), and glutathione (MD=17.08, 95% CI:8.65ï½25.5, P < 0.01). However, probiotic supplementation failed to enhance patients' psychological symptoms (SMD =0.18, 95% CI:-0.56ï½0.92, P = 0.64). CONCLUSIONS: Probiotic supplementation can enhance cognitive symptoms and decrease oxidative stress in older adults with cognitive impairment. However, it does not improve psychological symptoms. More research is needed to determine the effects of probiotic supplementation on gastrointestinal symptoms and sleep quality in this population. Further supplementation and improvement will be necessary once high-quality literature becomes available.
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Disfunción Cognitiva , Probióticos , Humanos , Anciano , Probióticos/uso terapéutico , Probióticos/farmacología , Cognición , Disfunción Cognitiva/terapiaRESUMEN
Precision chemistry demands miniaturized catalytic systems for sophisticated reactions with well-defined pathways. An ideal solution is to construct a nanoreactor system functioning as a chemistry laboratory to execute a full chemical process with molecular precision. However, existing nanoscale catalytic systems fail to in situ control reaction kinetics in a closed-loop manner, lacking the precision toward ultimate reaction efficiency. We find an inter-electrochemical gating effect when operating DNA framework-constructed enzyme cascade nanoreactors on a transistor, enabling in situ closed-loop reaction monitoring and modulation electrically. Therefore, a comprehensive system is developed, encapsulating nanoreactors, analyzers, and modulators, where the gate potential modulates enzyme activity and switches cascade reaction "ON" or "OFF." Such electric field-effect property enhances catalytic efficiency of enzyme by 343.4-fold and enables sensitive sarcosine assay for prostate cancer diagnoses, with a limit of detection five orders of magnitude lower than methodologies in clinical laboratory. By coupling with solid-state electronics, this work provides a perspective to construct intelligent nano-systems for precision chemistry.
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Bioensayo , Electricidad , Masculino , Humanos , Catálisis , Inteligencia , NanotecnologíaRESUMEN
Light response curve of photosynthesis (An-I curve) is a useful modeling tool to investigate how photosynthesis reacts with different abiotic factors, which would help quantify the response of photosynthetic rate to photosynthetically active radiation. Based on the mathematical characteristics of photosynthesis An-I models, we reviewed the advantages of using these model in practice and the potential caveats. We proposed the development of new mechanistic photosynthesis An-I models based on the primary light response and discussed its advantages in the field of plant ecology and physiology. Photosynthesis has three main steps, including the primary reaction, the assimilatory power forms, and the carbon assimilation. Changes in each step could directly affect the photochemical efficiency and carbon assimilation in photosynthesis. The primary reaction consists of a series of physical processes that are related to light energy absorption and utilization, including the absorption of light energy, the change of quantum state, and the transfer and de-excitation of exciton resonance of light-trapping pigment molecules. How-ever, the empirical photosynthesis An-I models can not explain some scenarios. For example, the non-photochemical quenching in plants increases with increasing light intensity in a non-linear manner. Further, the life-time of singlet chlorophyll molecules can be extended when plant light-harvesting pigment molecules absorb excessive light energy but would not be immediately used for the photochemical reaction. Meanwhile, the parameters obtained by fitting the mechanistic An-I curve model can not only reflect the primary photochemical reaction characteristics of plants, but also describe the physical characteristics of plant light harvesting pigment molecules, such as the number of light harvesting pigment molecules in the excited state (Nk) and effective light energy absorption cross-section (σik'). This can be used to further investigate the physical characteristics of light harvesting pigment molecules, including the light-response of Nk and σik' and the average life time of light harvesting pigment molecules in the lowest exciting state (τmin). In addition, it would be necessary to determine how to incorporate abiotic factors, such as temperature and CO2 concentration, into the mechanistic An-I curve model, as well as to determine the association between the abiotic factors and light harvesting pigment molecules, such as Nk, σik', and τmin.
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Clorofila , Fotosíntesis , Luz , Carbono , EcologíaRESUMEN
Investigation on intrinsic properties of photosynthetic pigment molecules participating in solar energy absorption and excitation, especially their eigen-absorption cross-section (σ ik) and effective absorption cross-section (σ ' ik), is important to understand photosynthesis. Here, we present the development and application of a new method to determine these parameters, based on a mechanistic model of the photosynthetic electron flow-light response. The analysis with our method of a series of previously collected chlorophyll a fluorescence data shows that the absorption cross-section of photosynthetic pigment molecules has different values of approximately 10-21 m2, for several photosynthetic organisms grown under various conditions: (1) the conifer Abies alba Mill., grown under high light or low light; (2) Taxus baccata L., grown under fertilization or non-fertilization conditions; (3) Glycine max L. (Merr.), grown under a CO2 concentration of 400 or 600 µmol CO2 mol-1 in a leaf chamber under shaded conditions; (4) Zea mays L., at temperatures of 30°C or 35°C in a leaf chamber; (5) Osmanthus fragrans Loureiro, with shaded-leaf or sun-leaf; and (6) the cyanobacterium Microcystis aeruginosa FACHB905, grown under two different nitrogen supplies. Our results show that σ ik has the same order of magnitude (approximately 10-21 m2), and σ ' ik for these species decreases with increasing light intensity, demonstrating the operation of a key regulatory mechanism to reduce solar absorption and avoid high light damage. Moreover, compared with other approaches, both σ ik and σ ' ik can be more easily estimated by our method, even under various growth conditions (e.g., different light environment; different CO2, NO2, O2, and O3 concentrations; air temperatures; or water stress), regardless of the type of the sample (e.g., dilute or concentrated cell suspensions or leaves). Our results also show that CO2 concentration and temperature have little effect on σ ik values for G. max and Z. mays. Consequently, our approach provides a powerful tool to investigate light energy absorption of photosynthetic pigment molecules and gives us new information on how plants and cyanobacteria modify their light-harvesting properties under different stress conditions.
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BACKGROUND: A positive resection margin is a major risk factor for local breast cancer recurrence after breast-conserving surgery (BCS). Preoperative imaging examinations are frequently employed to assess the surgical margin. AIM: To investigate the role and value of preoperative imaging examinations [magnetic resonance imaging (MRI), molybdenum target, and ultrasound] in evaluating margins for BCS. METHODS: A retrospective study was conducted on 323 breast cancer patients who met the criteria for BCS and consented to the procedure from January 2014 to July 2021. The study gathered preoperative imaging data (MRI, ultrasound, and molybdenum target examination) and intraoperative and postoperative pathological information. Based on their BCS outcomes, patients were categorized into positive and negative margin groups. Subsequently, the patients were randomly split into a training set (226 patients, approximately 70%) and a validation set (97 patients, approximately 30%). The imaging and pathological information was analyzed and summarized using R software. Non-conditional logistic regression and LASSO regression were conducted in the validation set to identify factors that might influence the failure of BCS. A column chart was generated and applied to the validation set to examine the relationship between pathological margin range and prognosis. This study aims to identify the risk factors associated with failure in BCS. RESULTS: The multivariate non-conditional logistic regression analysis demonstrated that various factors raise the risk of positive margins following BCS. These factors comprise non-mass enhancement (NME) on dynamic contrast-enhanced MRI, multiple focal vascular signs around the lesion on MRI, tumor size exceeding 2 cm, type III time-signal intensity curve, indistinct margins on molybdenum target examination, unclear margins on ultrasound examination, and estrogen receptor (ER) positivity in immunohistochemistry. LASSO regression was additionally employed in this study to identify four predictive factors for the model: ER, molybdenum target tumor type (MT Xmd Shape), maximum intensity projection imaging feature, and lesion type on MRI. The model constructed with these predictive factors exhibited strong consistency with the real-world scenario in both the training set and validation set. Particularly, the outcomes of the column chart model accurately predicted the likelihood of positive margins in BCS. CONCLUSION: The proposed column chart model effectively predicts the success of BCS for breast cancer. The model utilizes preoperative ultrasound, molybdenum target, MRI, and core needle biopsy pathology evaluation results, all of which align with the real-world scenario. Hence, our model can offer dependable guidance for clinical decision-making concerning BCS.
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Celery (Apium graveolens var. dulce), which belongs to the family Apiaceae, is one of the most widely cultivated vegetable crops in the world. During 2020 and 2021, celery plants with Fusarium yellows and root rot were observed in four approximately 0.3 ha sized fields located in Zhaili village (118°74'E, 36°67'N) of Shouguang city, Shandong province, China. Almost 50% of the plants were infected. Disease symptoms were comprised of wilting of outer-older leaves, overall stunted growth, rotted roots and stems, with eventual death of plants. A total of 7 diseased plants were collected from 4 fields and used for isolation and identification of the causal agent. Diseased root tissues were cut into 3 × 3 mm pieces from the edge of the rotting region, surface sterilized by soaking in 75% ethanol for 1 min, followed by three washes with sterile distilled water, and then placed on potato dextrose agar (PDA), and incubated at 28°C for 6 days in the dark. A total of 19 morphologically similar fungal isolates were obtained by single-spore subcultures. The colonies produced abundant, loosely floccose, white aerial mycelia and pale purple pigmentation on PDA. Microconidia were hyaline, zero to one septate, and ranged from 1.7 - 3.6 × 5.3 - 13.7 µm (n = 70). Macroconidia were falciform, hyaline, mostly four to five septate, and ranged from 2.2 - 4.2 × 12.4 - 45.4 µm in size (n = 70). These morphological characteristics were consistent with Fusarium oxysporum (Leslie and Summerell 2006). The genomic DNA of 19 isolates was extracted using the Plant Genomic DNA Kit (Tiangen, China). The translation elongation factor-1α (TEF-1α) and IGS rDNA regions were amplified with primers EF1/EF2 (O' Donnell et al. 1998) and iNL11/FoIGS-R (Epstein et al. 2017). BLAST analysis showed that 19 isolates were highly similar to Fusarium oxysporum, with 100% for TEF-1α (MN507109) and 99% for IGS rDNA (MT671188), respectively. The resulting 683-bp TEF-1α and 930-bp IGS rDNA sequences of isolate QC20091622 were deposited in GenBank with accession nos. ON260806 for TEF-1α and ON260805 for IGS rDNA, respectively. In a maximum-likelihood phylogenetic analysis based on TEF-1α and IGS rDNA sequences of F. oxysporum, using MEGAX software, isolate QC20091622 was grouped in the same clade with F. oxysporum f. sp. apii race 4, with a low bootstrap value of 54 between race 3 and race 4, indicating that the races are not distinguishable using only these two loci, as reported by Epstein et al (2022). Additional loci and other diagnostic methods are required to identify the race. Furthermore, the total DNA of 19 isolates was amplified by race-specific primers N4851-F/R (F. oxysporum f. sp. apii race 2) and N3875-2F/R (race 4), respectively (Epstein et al. 2017), and 187 bp product was amplified with primer pair N3875-2F/R, but none with primer pair N4851-F/R, so the isolates were identified as F. oxysporum f. sp. apii race 4. Pathogenicity of the 19 isolates was tested on potted celery plants (cv. 'Baimiao'). Ten healthy 6-week-old celery plants were inoculated by dipping the roots in a conidial suspension (107 conidia/mL) for 30 min. Control plants were dipped in sterile distilled water. The plants were then grown in a greenhouse maintained at 15°C (night)/26°C (day) and 90% relative humidity with natural daylight. The pathogenicity test was repeated twice. All inoculated plants started to wilt and developed root rot symptoms 14 days later, which were similar to those observed in the fields. The control plants remained healthy. F. oxysporum f. sp. apii race 4 was reisolated from the symptomatic roots, and their identity was confirmed by PCR, fulfilling Koch's postulates. To our knowledge, this is the first report of F. oxysporum f. sp. apii race 4 causing root rot on celery in China. F. oxysporum f. sp. apii race 4 has been a destructive pathogen in celery, prevention and control measures should be considered.
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Background: Individualized decisions are required in early-stage breast cancer patients. We aimed to establish a novel model for predicting non-sentinel lymph node (SLN) metastases in patients with positive SLNs, using preoperative and intraoperative characteristics and inflammatory indicators. Methods: The data of 489 patients with invasive breast cancer were retrospectively collected from Xuanwu Hospital between 2014 and 2021. Among them, 96 patients with at least one positive SLN were used to build the predictive model. Univariate and multivariate analyses were performed to identify the risk factors of non-SLN metastases. A nomogram was developed using these risk factors and was validated by calibration curves. The area under the receiver operating characteristics curve (AUC) and decision curve analyses (DCA) were used to compare our novel nomogram with the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram. Cross-validation was performed for further internal validation of the predictive model. External validation was conducted using another treatment group (n=46 patients) in Xuanwu Hospital. Results: Non-SLN metastases occurred in 42 of the 83 patients with positive SLNs (50.6%). Multivariate stepwise logistic regression indicated that the risk factors were age (P=0.032), number of positive SLNs (P=0.020), number of negative SLNs (P=0.011), resected tumor size (P=0.038), and monocyte count (P=0.012). A predictive model was developed and virtualized by nomogram using these five risk factors. The AUC of our nomogram was 0.867, which was significantly higher than that of the MSKCC model. DCA also showed a superior clinical value for our novel nomogram. After 10-fold cross-validation with 400 times repetitions, the AUC of our model was still 0.830. External validation of our model showed an AUC of 0.727. The model was well-calibrated in the internal and external validation series. Conclusions: A five-factor nomogram was developed for predicting non-SLN metastases in early-stage breast cancer patients. This novel tool exhibited good accuracy and could assist clinicians with intraoperative decisions in breast cancer patients with positive SLNs.