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1.
World J Gastrointest Surg ; 16(6): 1791-1802, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38983329

RESUMO

BACKGROUND: Metastatic colorectal cancer (mCRC) is a common malignancy whose treatment has been a clinical challenge. Cancer-specific survival (CSS) plays a crucial role in assessing patient prognosis and treatment outcomes. However, there is still limited research on the factors affecting CSS in mCRC patients and their correlation. AIM: To predict CSS, we developed a new nomogram model and risk grading system to classify risk levels in patients with mCRC. METHODS: Data were extracted from the United States Surveillance, Epidemiology, and End Results database from 2018 to 2023. All eligible patients were randomly divided into a training cohort and a validation cohort. The Cox proportional hazards model was used to investigate the independent risk factors for CSS. A new nomogram model was developed to predict CSS and was evaluated through internal and external validation. RESULTS: A multivariate Cox proportional risk model was used to identify independent risk factors for CSS. Then, new CSS columns were developed based on these factors. The consistency index (C-index) of the histogram was 0.718 (95%CI: 0.712-0.725), and that of the validation cohort was 0.722 (95%CI: 0.711-0.732), indicating good discrimination ability and better performance than tumor-node-metastasis staging (C-index: 0.712-0.732). For the training set, 0.533, 95%CI: 0.525-0.540; for the verification set, 0.524, 95%CI: 0.513-0.535. The calibration map and clinical decision curve showed good agreement and good potential clinical validity. The risk grading system divided all patients into three groups, and the Kaplan-Meier curve showed good stratification and differentiation of CSS between different groups. The median CSS times in the low-risk, medium-risk, and high-risk groups were 36 months (95%CI: 34.987-37.013), 18 months (95%CI: 17.273-18.727), and 5 months (95%CI: 4.503-5.497), respectively. CONCLUSION: Our study developed a new nomogram model to predict CSS in patients with synchronous mCRC. In addition, the risk-grading system helps to accurately assess patient prognosis and guide treatment.

2.
ACS Appl Mater Interfaces ; 16(28): 36289-36294, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38954646

RESUMO

Na-O2 batteries have emerged as promising candidates due to their high theoretical energy density (1,601 Wh kg-1), the potential for high energy storage efficiency, and the abundance of sodium in the earth's crust. Considering the safety issue, quasi-solid-state composite polymer electrolytes are among the promising solid-state electrolyte candidates. Their higher mechanical toughness provides superior resistance to dendritic penetration compared with traditional liquid electrolytes. The flexibility of the composite polymer electrolyte matrix allows it to conform to various battery configurations and considerably reduces safety concerns related to the combustion risks associated with conventional liquid electrolytes. In this study, we employed poly(ethylene oxide) (PEO) and sodium bis(trifluoromethanesulfonyl)imide (NaTFSI) as the polymer matrix and sodium ion-conducting agent, respectively. We incorporated nanosized NZSP (25 wt %) to create the composite polymer electrolyte membrane. This CPE design facilitates ion conduction pathways through both sodium salt and NZSP. By utilizing a liquid electrolyte infiltration method, we successfully enhanced its ionic conductivity, achieving an ionic conductivity of 10-4 S cm-1 at room temperature.

3.
Beilstein J Nanotechnol ; 15: 664-677, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887525

RESUMO

Hair, or hair-like fibrillar structures, are ubiquitous in biology, from fur on the bodies of mammals, over trichomes of plants, to the mastigonemes on the flagella of single-celled organisms. While these long and slender protuberances are passive, they are multifunctional and help to mediate interactions with the environment. They provide thermal insulation, sensory information, reversible adhesion, and surface modulation (e.g., superhydrophobicity). This review will present various functions that biological hairs have been discovered to carry out, with the hairs spanning across six orders of magnitude in size, from the millimeter-thick fur of mammals down to the nanometer-thick fibrillar ultrastructures on bateriophages. The hairs are categorized according to their functions, including protection (e.g., thermal regulation and defense), locomotion, feeding, and sensing. By understanding the versatile functions of biological hairs, bio-inspired solutions may be developed across length scales.

4.
World J Microbiol Biotechnol ; 40(7): 232, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38834810

RESUMO

Microbially induced carbonate precipitation (MICP) has been used to cure rare earth slags (RES) containing radionuclides (e.g. Th and U) and heavy metals with favorable results. However, the role of microbial extracellular polymeric substances (EPS) in MICP curing RES remains unclear. In this study, the EPS of Lysinibacillus sphaericus K-1 was extracted for the experiments of adsorption, inducing calcium carbonate (CaCO3) precipitation and curing of RES. The role of EPS in in MICP curing RES and stabilizing radionuclides and heavy metals was analyzed by evaluating the concentration and morphological distribution of radionuclides and heavy metals, and the compressive strength of the cured body. The results indicate that the adsorption efficiencies of EPS for Th (IV), U (VI), Cu2+, Pb2+, Zn2+, and Cd2+ were 44.83%, 45.83%, 53.7%, 61.3%, 42.1%, and 77.85%, respectively. The addition of EPS solution resulted in the formation of nanoscale spherical particles on the microorganism surface, which could act as an accumulating skeleton to facilitate the formation of CaCO3. After adding 20 mL of EPS solution during the curing process (Treat group), the maximum unconfined compressive strength (UCS) of the cured body reached 1.922 MPa, which was 12.13% higher than the CK group. The contents of exchangeable Th (IV) and U (VI) in the cured bodies of the Treat group decreased by 3.35% and 4.93%, respectively, compared with the CK group. Therefore, EPS enhances the effect of MICP curing RES and reduces the potential environmental problems that may be caused by radionuclides and heavy metals during the long-term sequestration of RES.


Assuntos
Bacillaceae , Carbonato de Cálcio , Matriz Extracelular de Substâncias Poliméricas , Metais Pesados , Tório , Urânio , Urânio/química , Urânio/metabolismo , Carbonato de Cálcio/química , Tório/química , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Matriz Extracelular de Substâncias Poliméricas/química , Bacillaceae/metabolismo , Metais Terras Raras/química , Adsorção , Precipitação Química
5.
Cell Biol Toxicol ; 40(1): 37, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777957

RESUMO

Bisphenol A (BPA) is a common component in the manufacture of daily plastic consumer goods. Recent studies have suggested that prenatal exposure to BPA can increase the susceptibility of offspring to mental illness, although the underlying mechanisms remain unclear. In this study, we performed transcriptomic and epigenomic profiling in the adult mouse brain following prenatal exposure to low-dose BPA. We observed a sex-specific transcriptional dysregulation in the cortex, with more significant differentially expressed genes was observed in adult cortex from male offspring. Moreover, the upregulated genes primarily influenced neuronal functions, while the downregulated genes were significantly associated with energy metabolism pathways. More evidence supporting impaired mitochondrial function included a decreased ATP level and a reduced number of mitochondria in the cortical neuron of the BPA group. We further investigated the higher-order chromatin regulatory patterns of DEGs by incorporating published Hi-C data. Interestingly, we found that upregulated genes exhibited more distal interactions with multiple enhancers, while downregulated genes displayed relatively short-range interactions among adjacent genes. Our data further revealed decreased H3K9me3 signal on the distal enhancers of upregulated genes, whereas increased DNA methylation and H3K27me3 signals on the promoters of downregulated genes. In summary, our study provides compelling evidence for the potential health risks associated with prenatal exposure to BPA, and uncovers sex-specific transcriptional changes with a complex interplay of multiple epigenetic mechanisms.


Assuntos
Compostos Benzidrílicos , Encéfalo , Metilação de DNA , Epigênese Genética , Fenóis , Efeitos Tardios da Exposição Pré-Natal , Animais , Compostos Benzidrílicos/toxicidade , Fenóis/toxicidade , Feminino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Epigênese Genética/efeitos dos fármacos , Masculino , Camundongos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Camundongos Endogâmicos C57BL
7.
Cancer Manag Res ; 16: 491-505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800665

RESUMO

Purpose: We aimed to develop a nomogram to predict prognosis of HR+ HER2- breast cancer patients and guide the application of postoperative adjuvant chemotherapy. Methods: We identified 310 eligible HR+ HER- breast cancer patients and randomly divided the database into a training group and a validation group. The endpoint was disease free survival (DFS). Concordance index (C-index), area under the curve (AUC) and calibration curves were used to evaluate predictive accuracy and discriminative ability of the nomogram. We also compared the predictive accuracy and discriminative ability of our nomogram with the eighth AJCC staging system using overall data. Results: According to the training group, platelet-to-lymphocyte ratio (PLR), tumor size, positive lymph nodes and Ki-67 index were used to construct the nomogram of DFS. The C-index of DFS was 0.708 (95% CI: 0.623-0.793) in the training group and 0.67 (95% CI: 0.544-0.796) in the validation group. The calibration curves revealed great consistencies in both groups. Conclusion: We have developed and validated a novel and practical nomogram that can provide individual prediction of DFS for patients with HR+ HER- breast cancer. This nomogram may help clinicians in risk consulting and guiding the application of postoperative adjuvant chemotherapy.

8.
Elife ; 132024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752724

RESUMO

Eukaryotes swim with coordinated flagellar (ciliary) beating and steer by fine-tuning the coordination. The model organism for studying flagellate motility, Chlamydomonas reinhardtii, employs synchronous, breaststroke-like flagellar beating to swim, and it modulates the beating amplitudes differentially to steer. This strategy hinges on both inherent flagellar asymmetries (e.g. different response to chemical messengers) and such asymmetries being effectively coordinated in the synchronous beating. In C. reinhardtii, the synchrony of beating is known to be supported by a mechanical connection between flagella; however, how flagellar asymmetries persist in the synchrony remains elusive. For example, it has been speculated for decades that one flagellum leads the beating, as its dynamic properties (i.e. frequency, waveform, etc.) appear to be copied by the other one. In this study, we combine experiments, computations, and modeling efforts to elucidate the roles played by each flagellum in synchronous beating. With a non-invasive technique to selectively load each flagellum, we show that the coordinated beating essentially only responds to load exerted on the cis flagellum; and that such asymmetry in response derives from a unilateral coupling between the two flagella. Our results highlight a distinct role for each flagellum in coordination and have implication for biflagellates' tactic behaviors.


Many single-cell organisms use tiny hair-like structures called flagella to move around. To direct this movement, the flagella must work together and beat in a synchronous manner. In some organisms, coordination is achieved by each flagellum reacting to the flow generated by neighbouring flagella. In others, flagella are joined together by fiber connections between their bases, which allow movement to be coordinated through mechanical signals sent between flagella. One such organism is Chlamydomonas reinhardtii, a type of algae frequently used to study flagellar coordination. Its two flagella ­ named trans and cis because of their positions relative to the cell's eyespot ­ propel the cell through water using breaststroke-like movements. To steer, C. reinhardtii adjusts the strength of the strokes made by each flagellum. Despite this asymmetry, the flagella must continue to beat in synchrony to move efficiently. To understand how the cell manages these differences, Wei et al. exposed each flagellum to carefully generated oscillations in water so that each was exposed to different forces and their separate responses could be measured. A combination of experiments, modelling and computer simulations were then used to work out how the two flagella coordinate to steer the cell. Wei et al. found that only the cis flagellum coordinates the beating, with the trans flagellum simply copying the motion of the cis. A direct consequence of such one-way coupling is that only forces on the cis flagellum influence the coordinated beating dynamics of both flagella. These findings shed light on the unique roles of each flagellum in the coordinated movement in C. reinhardtii and have implications for how other organisms with mechanically-connected flagella navigate their environments.


Assuntos
Chlamydomonas reinhardtii , Flagelos , Chlamydomonas reinhardtii/fisiologia , Flagelos/fisiologia
9.
Curr Pharm Des ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38676524

RESUMO

BACKGROUND: Bear Bile Powder (BBP) is a traditional Chinese medicine. It has been widely used in clinical practices and has shown a good anti-inflammatory effect. However, its effectiveness in treating Ulcerative Colitis (UC) has not yet been studied. OBJECTIVE: To explore the therapeutic effect of BBP on ulcerative colitis and its potential mechanism by combining acute ulcerative colitis mouse models and comprehensively observing various physiological and biochemical indexes of mice. METHODS: The acute ulcerative colitis model was induced by drinking water containing dextran sulfate sodium salt (DSS) for 7 days. Studies were divided into Control, DSS, DSS+ Sulfasalazine (SASP, 450 mg/kg), and DSS + bear bile powder group (BBP, 320 mg/kg). The Disease Activity Index (DAI) and colonic tissue damage of mice were evaluated. Tissue immunofluorescence and western blot were used to determine related tight Junction Proteins (TJs), and 16S V34 amplicon was used to analyze intestinal microorganisms. The therapeutic effect of BBP on ulcerative colitis model mice was studied comprehensively. RESULTS: After treatment, BBP can significantly improve the physiological condition of acute UC mice and reduce DAI fraction. Compared with the DSS group, the BBP group significantly increased the colon length and significantly decreased the injury fraction of acute UC mice. Regarding the intestinal mechanical barrier, BBP significantly increased the expression of ZO-1, Occludin, and Claudin 1 protein in colon tissue. In terms of microbial community, the intestinal microbial diversity of mice decreased after the administration of BBP, but there was no significant difference in structural composition between the BBP group and the Control group. By comparing the four groups of species with significant differences, it was found that the BBP group significantly reduced the abundance of specific harmful microorganisms at the order, family, genus, and species levels. CONCLUSION: Oral administration of a certain dose of BBP can significantly improve the symptoms of ulcerative colitis in mice. Part of the reason may be that it increases the expression of tight junction proteins, regulates specific flora in the intestine of mice, and maintains intestinal barrier homeostasis. In the future, the clinical application value of BBP will be explored, and BBP will be developed as a drug with the potential to treat UC and alleviate the pain of UC patients.

10.
Nat Commun ; 15(1): 2489, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509103

RESUMO

The elevation gradient has long been known to be vital in shaping the structure and function of terrestrial ecosystems, but little is known about the elevation-dependent pattern of net CO2 uptake, denoted by net ecosystem productivity (NEP). Here, by analyzing data from 203 eddy covariance sites across China, we report a negative linear elevation-dependent pattern of NEP, collectively shaped by varying hydrothermal factors, nutrient supply, and ecosystem types. Furthermore, the NEP shows a higher temperature sensitivity in high-elevation environments (3000-5000 m) compared with the lower-elevation environments (<3000 m). Model ensemble and satellite-based observations consistently reveal more rapid relative changes in NEP in high-elevation environments during the last four decades. Machine learning also predicts a stronger relative increase in high-elevation environments, whereas less change is expected at lower elevations. We therefore conclude a varying elevation-dependent pattern of the NEP of terrestrial ecosystems in China, although there is significant uncertainty involved.


Assuntos
Dióxido de Carbono , Ecossistema , Temperatura , Temperatura Alta , China
11.
Medicine (Baltimore) ; 103(4): e36924, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38277562

RESUMO

BACKGROUND: One of the risk factors for esophageal adenocarcinoma is achalasia, an esophageal motility disorder that is typically treated surgically through laparotomy or laparoscopic surgery. The risk factors of gastric cardia cancer are also similar to esophageal adenocarcinoma due to the anatomical location of the gastric cardia close to the esophagus. There is currently no clinical evidence that achalching has a correlation with gastric cardia cancer. CASE SUMMARY: We report the case of an 85-year-old female patient was admitted to our department with dysphagia for 6 months. She underwent a dissecting Heller myotomy for pancreatic achalasia in 2006, with occasional postoperative symptoms of reflux and heartburn. Outpatient upper gastrointestinal imaging was suggestive of cardia cancer, and gastroscopic pathological findings were suggestive of moderately-lowly-differentiated adenocarcinoma. The patient was admitted to the operating room on August 30, 2022 to undergo radical pancreatic cancer surgery plus abdominal adhesion release, and postoperative review of the upper gastrointestinal imaging showed a patent anastomosis with no spillage, filling of the residual stomach, and duodenal visualization. CONCLUSION: Postoperative patients with achalasia often have symptoms of reflux, which may be one of the factors for the development of pancreatic cancer in this patient, thus requiring clinicians to pay more attention to the use of antireflux procedures in the surgical treatment of pancreatic achalasia. And the choice of which modality to perform surgery in patients with previous surgical history is also one of the points to be discussed.


Assuntos
Carcinoma , Cárdia , Acalasia Esofágica , Neoplasias Gástricas , Idoso de 80 Anos ou mais , Feminino , Humanos , Adenocarcinoma/diagnóstico , Carcinoma/diagnóstico , Acalasia Esofágica/cirurgia , Refluxo Gastroesofágico/etiologia , Miotomia de Heller/métodos , Laparoscopia/métodos , Neoplasias Pancreáticas/cirurgia , Neoplasias Gástricas/diagnóstico , Resultado do Tratamento
12.
BMC Pediatr ; 24(1): 51, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38229006

RESUMO

OBJECTIVE: The study aimed to explore the effectiveness of bedside lung ultrasound (LUS) combined with the PaO2/FiO2 (P/F) ratio in evaluating the outcomes of high-flow nasal cannula (HFNC) therapy in infants with severe pneumonia. METHODS: This retrospective study analyzed the clinical data of 150 infants diagnosed with severe pneumonia and treated with HFNC therapy at our hospital from January 2021 to December 2021. These patients were divided into two groups based on their treatment outcomes: the HFNC success group (n = 112) and the HFNC failure group (n = 38). LUS was utilized to evaluate the patients' lung conditions, and blood gas results were recorded for both groups upon admission and after 12 h of HFNC therapy. RESULTS: At admission, no significant differences were observed between the two groups in terms of age, gender, respiratory rate, partial pressure of oxygen, and partial pressure of carbon dioxide. However, the P/F ratios at admission and after 12 h of HFNC therapy were significantly lower in the HFNC failure group (193.08 ± 49.14, 228.63 ± 80.17, respectively) compared to the HFNC success group (248.51 ± 64.44, 288.93 ± 57.17, respectively) (p < 0.05). Likewise, LUS scores at admission and after 12 h were significantly higher in the failure group (18.42 ± 5.3, 18.03 ± 5.36, respectively) than in the success group (15.09 ± 4.66, 10.71 ± 3.78, respectively) (p < 0.05). Notably, in the success group, both P/F ratios and LUS scores showed significant improvement after 12 h of HFNC therapy, a trend not observed in the failure group. Multivariate regression analysis indicated that lower P/F ratios and higher LUS scores at admission and after 12 h were predictive of a greater risk of HFNC failure. ROC analysis demonstrated that an LUS score > 20.5 at admission predicted HFNC therapy failure with an AUC of 0.695, a sensitivity of 44.7%, and a specificity of 91.1%. A LUS score > 15.5 after 12 h of HFNC therapy had an AUC of 0.874, with 65.8% sensitivity and 89.3% specificity. An admission P/F ratio < 225.5 predicted HFNC therapy failure with an AUC of 0.739, 60.7% sensitivity, and 71.1% specificity, while a P/F ratio < 256.5 after 12 h of HFNC therapy had an AUC of 0.811, 74.1% sensitivity, and 73.7% specificity. CONCLUSION: Decreased LUS scores and increased P/F ratio demonstrate a strong correlation with successful HFNC treatment outcomes in infants with severe pneumonia. These findings may provide valuable support for clinicians in managing such cases.


Assuntos
Pneumonia , Insuficiência Respiratória , Lactente , Humanos , Cânula , Estudos Retrospectivos , Oxigenoterapia/métodos , Pulmão/diagnóstico por imagem , Pneumonia/diagnóstico por imagem , Pneumonia/terapia , Oxigênio , Insuficiência Respiratória/terapia
13.
Acta Radiol ; 65(5): 406-413, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38196245

RESUMO

BACKGROUND: Surveillance of pancreatic cysts are necessary due to risk of malignant transformation. However, reported progression rates to advanced neoplasia are variable and the high frequency of surveillance scans may pose a considerable burden on healthcare resources. PURPOSE: To validate the effectiveness of the Fukuoka Guidelines surveillance regime and determine if a longer surveillance interval can be established. MATERIAL AND METHODS: All magnetic resonance imaging (MRI) studies of the pancreas performed at our institution between January 2014 and December 2016 with at least one pancreatic cystic lesion and follow-up MRI or computed tomography (CT) over at least two years were reviewed for size, worrisome feature (WF), and high-risk stigmata (HRS) at diagnosis and follow-up imaging (up to year 6). Reference standards for advanced neoplasia were based on endoscopic ultrasound, fine needle aspiration cytology, or the presence of ≥2 WF or ≥1 HRS on imaging. Comparison of MRI features of progression and outcomes of diagnostic endpoints between lesions <20 mm and ≥20 mm was performed. RESULTS: A total of 270 patients were included (201 cysts <20 mm, 69 cysts ≥20 mm). Compared with cysts <20 mm, cysts ≥20 mm were more likely to be associated with WF or HRS (40.6% vs. 12.4%; P ≤0.00001), demonstrate increase in size of ≥5 mm in two years (20.3% vs. 10.9%; P = 0.049), and develop advanced neoplasia (24.6% vs. 0.5%; P <0.00001). CONCLUSION: Pancreatic cysts <20 mm have a low risk of developing WF and HRS and surveillance interval may be lengthened.


Assuntos
Imageamento por Ressonância Magnética , Cisto Pancreático , Tomografia Computadorizada por Raios X , Humanos , Cisto Pancreático/diagnóstico por imagem , Cisto Pancreático/patologia , Feminino , Masculino , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Idoso , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Adulto , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Progressão da Doença , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Idoso de 80 Anos ou mais , Fatores de Tempo
14.
J Magn Reson Imaging ; 59(3): 954-963, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37312270

RESUMO

BACKGROUND: Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter in human brains, playing a role in the pathogenesis of various psychiatric disorders. Current methods have some non-neglectable shortcomings and noninvasive and accurate detection of GABA in human brains is long-term challenge. PURPOSE: To develop a pulse sequence capable of selectively detecting and quantifying the 1 H signal of GABA in human brains based on optimal controlled spin singlet order. STUDY TYPE: Prospective. SUBJECTS/PHANTOM: A phantom of GABA (pH = 7.3 ± 0.1) and 11 healthy subjects (5 females and 6 males, body mass index: 21 ± 3 kg/m2 , age: 25 ± 4 years). FIELD STRENGTH/SEQUENCE: 7 Tesla, 3 Tesla, GABA-targeted magnetic resonance spectroscopy (GABA-MRS-7 T, GABA-MRS-3 T), magnetization prepared two rapid acquisition gradient echoes sequence. ASSESSMENT: By using the developed pulse sequences applied on the phantom and healthy subjects, the signals of GABA were successfully selectively probed. Quantification of the signals yields the concentration of GABA in the dorsal anterior cingulate cortex (dACC) in human brains. STATISTICAL TESTS: Frequency. RESULTS: The 1 H signals of GABA in the phantom and in the human brains of healthy subjects were successfully detected. The concentration of GABA in the dACC of human brains was 3.3 ± 1.5 mM. DATA CONCLUSION: The developed pulse sequences can be used to selectively probe the 1 H MR signals of GABA in human brains in vivo. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY STAGE: 1.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Estudos Prospectivos , Espectroscopia de Ressonância Magnética/métodos , Ácido gama-Aminobutírico
15.
Chemosphere ; 346: 140645, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37951407

RESUMO

The advantages of microbial induced carbonate precipitation (MICP) as bio-cementation technology for tailings-solidification are under extensive investigation. In order to improve performance of bio-cementation, many strengthening materials were applied to the bio-cementation of tailings. Steel slag (SS) is a kind of industrial solid waste, its chemical composition and mineral composition are similar to cement, and it has a certain application prospect as an auxiliary cementing material. In this study, the properties and mechanism of SS strengthening MICP cementation of cyanide tailings (CT) were investigated. The results showed that Sporosarcina pasteurii growth is not inhibited by SS, and Sporosarcina pasteurii can promote the hydration reaction of SS, providing a suitable alkaline environment and Ca2+, promoting the production of more CaCO3 in the MICP process. When 200 mL of CT leachate was added 1.4 g SS (200-400 mesh), the adsorption of Cu, Pb, Zn, Cd, total cyanide (T-CN), and free cyanide (F-CN) reached 48.05%, 44.28%, 36.25%, 16.67%, 79.05%, and 67.20%, respectively. The maximum unconfined compressive strength(UCS) of the cemented body (with 5%, 150 mesh SS) was 1.97 MPa, which was 3.396 times as high as that without SS. The cemented body with the addition of SS (5%, 150 mesh) contained more carbonate bound Cu (2.75%), Pb (4.89%), Zn (5.37%), and Cd (5.75%), and less exchangeable Cu (3.65%), Pb (6.85%), Zn (2.27%), and Cd (4.42%) than that without SS. In summary, the addition of SS improved the UCS of cemented bodies and the stability of heavy metals and cyanide, reduced the environmental risks existing in the process of CT storage. Meanwhile, it also provides new ideas for resource utilization of industrial solid waste SS and improvement of mine filling materials.


Assuntos
Metais Pesados , Resíduos Sólidos , Aço , Cimentação , Cianetos , Cádmio , Chumbo , Metais Pesados/química , Carbonatos/química , Carbonato de Cálcio
16.
Opt Lett ; 48(23): 6188-6191, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039223

RESUMO

Simultaneous linewidth narrowing of a multi-wavelength laser array with an arbitrary wavelength spacing based on Rayleigh backscattering is experimentally demonstrated. Rayleigh backscattering from a single 30 m high numerical aperture fiber (HNAF) is employed to simultaneously narrow the linewidths of a DFB laser array consisting of four distributed feedback (DFB) semiconductor lasers with different wavelengths. Experimental results show that the instantaneous linewidths of the four DFB lasers can be simultaneously narrowed from megahertz to kilohertz no matter whether the wavelength spacing between the lasers is equally spaced or not, verifying the self-adaptivity of Rayleigh backscattering on laser linewidth narrowing. The method demonstrated here is also applicable for on-chip waveguides without wavelength dependence, providing a more compact narrow linewidth laser array for the wavelength-multiplexing division system and other promising applications.

17.
Nature ; 623(7986): 397-405, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37914940

RESUMO

Microglia are specialized brain-resident macrophages that arise from primitive macrophages colonizing the embryonic brain1. Microglia contribute to multiple aspects of brain development, but their precise roles in the early human brain remain poorly understood owing to limited access to relevant tissues2-6. The generation of brain organoids from human induced pluripotent stem cells recapitulates some key features of human embryonic brain development7-10. However, current approaches do not incorporate microglia or address their role in organoid maturation11-21. Here we generated microglia-sufficient brain organoids by coculturing brain organoids with primitive-like macrophages generated from the same human induced pluripotent stem cells (iMac)22. In organoid cocultures, iMac differentiated into cells with microglia-like phenotypes and functions (iMicro) and modulated neuronal progenitor cell (NPC) differentiation, limiting NPC proliferation and promoting axonogenesis. Mechanistically, iMicro contained high levels of PLIN2+ lipid droplets that exported cholesterol and its esters, which were taken up by NPCs in the organoids. We also detected PLIN2+ lipid droplet-loaded microglia in mouse and human embryonic brains. Overall, our approach substantially advances current human brain organoid approaches by incorporating microglial cells, as illustrated by the discovery of a key pathway of lipid-mediated crosstalk between microglia and NPCs that leads to improved neurogenesis.


Assuntos
Encéfalo , Colesterol , Células-Tronco Pluripotentes Induzidas , Microglia , Células-Tronco Neurais , Neurogênese , Organoides , Animais , Humanos , Camundongos , Encéfalo/citologia , Encéfalo/metabolismo , Diferenciação Celular , Células-Tronco Pluripotentes Induzidas/citologia , Microglia/citologia , Microglia/metabolismo , Organoides/citologia , Organoides/metabolismo , Colesterol/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Axônios , Proliferação de Células , Ésteres/metabolismo , Gotículas Lipídicas/metabolismo
18.
Sensors (Basel) ; 23(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37960556

RESUMO

Stockouts constitute a major challenge in the retail industry. Stockouts are caused by errors related to manual stockkeeping and by the misplacement of items on shelves. Such errors account for up to 4% of lost sales. Real-time inventory management systems for misplaced items or missing stock detection in retail stores are limited. Accordingly, a conductive polymer-based interactive shelving system for real-time inventory management is developed. The system comprises an 80 × 48 sensor array fabricated by screen-printing a piezoresistive carbon-based conductive polymer layer onto gold interdigitated electrodes deposited on a flexible substrate. Each sensing pixel has dimensions of 5 mm × 5 mm and a sensing area of 4 mm × 4 mm. The sensor mat can detect the shape and weight features of stockkeeping units (SKUs), which can then be analyzed by a TensorFlow model for SKU identification. The developed system is characterized for functional resistance range, uniformity, repeatability, and durability. The accuracy of SKU identification achieved using shape features only and the accuracy of SKU identification achieved using both shape and weight features is 95% and 99.2%, respectively. The key novelty of the work is the development of a deep learning-embedded interactive smart shelving system for retail inventory management by using the shape and weight features of SKU. Also, the developed system helps to detect the SKU if they are stacked one over the other. Furthermore, multiple sensor mats implemented on various shelves in a retail store can be modularized and integrated for monitoring under the control of a single PC. Accordingly, the proposed retail inventory tracking system can facilitate the development of automated "humanless" shops.

19.
Chemosphere ; 345: 140354, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37832879

RESUMO

Cyanide extraction dominates the gold smelting industry, which leads to the generation of large amounts of cyanide-containing wastewater. In this study, Aneurinibacillus tyrosinisolvens strain named JK-1 was used for cyanide wastewater biodegradation. First, we tested the performance of JK-1 in degrading cyanide under different conditions. Then, we screened metabolic compounds and pathways associated with cyanide degradation by JK-1. Finally, we explored the potential JK-1-mediated cyanide degradation pathway. Our results showed that the optimal pH and temperature for cyanide biodegradation were 7.0 and 30 °C, respectively; under these conditions, a degradation rate of >98% was achieved within 48 h. Untargeted metabolomics results showed that increased cyanide concentration decreased the abundance of metabolic compounds by 71.1% but upregulated 32 metabolic pathways. The Kyoto Encyclopedia of Genes and Genomes enrichment results revealed significant changes in amino acid metabolism pathways during cyanide degradation by JK-1, including cyanoamino acid metabolism, ß-alanine metabolism, and glutamate metabolism. Differential metabolic compounds included acetyl-CoA, l-asparagine, l-glutamic acid, l-phenylalanine, and l-glutamine. These results confirmed that cyanide degradation by JK-1 occurs through amino acid assimilation. This study provides new insights into the mechanism of cyanide biodegradation, which can be applied in the treatment of cyanide wastewater or tailings.


Assuntos
Cianetos , Águas Residuárias , Cianetos/análise , Biodegradação Ambiental , Reatores Biológicos , Aminoácidos
20.
Ying Yong Sheng Tai Xue Bao ; 34(9): 2429-2435, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37899109

RESUMO

The three provinces of Northeast China are crucial to national commodity grain production. Soils in those areas have begun to severely degrade after long-term high-intensity use, with wind erosion as one of the main reasons. Based on meteorological and soil data from 1981 to 2019, we evaluated the spatial-temporal characteristics of wind erosion on bare land in the three provinces of Northeast China by using the revised wind erosion equation (RWEQ), and analyzed the contributions of meteorological factors to wind erosion on bare land. The results showed that, the meteorological factors of wind erosion were overall high in southwestern part and low in northeastern part of the region. In general, wind erosion in the region was substantial, especially in Liaoning. During the 39 years, wind erosion significantly increased throughout the whole year and during the growing season, at a rate of 129 and 105 t·km-2 per decade, respectively. The obvious increase in wind erosion was observed in the northwest Liaoning, Liaohe Plain, and Changbai Mountain area. Wind speed and air temperature were the main factors affecting wind erosion during the year and non-growing season, which contributed less during the growing season when precipitation contributed the most. We concluded that climate change has aggravated soil wind erosion in the three provinces of Northeast China.


Assuntos
Mudança Climática , Vento , Solo , China , Temperatura
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