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2.
ACS Omega ; 9(25): 26973-26982, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38947776

RESUMO

With the development of high-rise and large-scale modern structures, traditional concrete has become a design limitation due to its excessive dead weight. High-strength lightweight concrete is being emphasized. Lightweight concrete has low density and the characteristics of a brittle material. This is an important factor affecting the strength and ductility of the lightweight concrete. To improve these shortcomings and proffer solutions, a three-phase composite lightweight concrete was prepared using a combination of tumbling and molding methods. This paper investigates the various influencing factors such as the stacking volume fraction of GFR-EMS, the type of fiber, and the content and length of fiber in the matrix. Studies have shown that the addition of fibers significantly increases the compressive strength of the concrete. The compressive strength of concrete with a 12 mm basalt fiber (BF) (1.5%) admixture is 9.08 MPa, which is 62.43% higher than that of concrete without the fiber admixture. The compressive strength was increased by 27.53 and 21.88% compared to concrete containing 3 mm BF (1.5%) and 0.5% BF (12 mm), respectively. Fibers can fill the pore defects within the matrix. Mutually overlapping fibers easily form a network structure to improve the bond between the cement matrix and the aggregate particles. The compressive strength of lightweight concrete with the addition of BF was 16.71% higher than that with the addition of polypropylene fiber (PPF) with the same length and content of fibers. BF has been shown to be more effective in improving the mechanical properties of concrete. In this work, the compressive mechanism and optimum preparation parameters of a three-phase composite lightweight concrete were analyzed through compression tests. This provides some insights into the development of lightweight concrete.

3.
Nat Med ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956195

RESUMO

Recent single-arm studies involving neoadjuvant camrelizumab, a PD-1 inhibitor, plus chemotherapy for resectable locally advanced esophageal squamous cell carcinoma (LA-ESCC) have shown promising results. This multicenter, randomized, open-label phase 3 trial aimed to further assess the efficacy and safety of neoadjuvant camrelizumab plus chemotherapy followed by adjuvant camrelizumab, compared to neoadjuvant chemotherapy alone. A total of 391 patients with resectable thoracic LA-ESCC (T1b-3N1-3M0 or T3N0M0) were stratified by clinical stage (I/II, III or IVA) and randomized in a 1:1:1 ratio to undergo two cycles of neoadjuvant therapy. Treatments included camrelizumab, albumin-bound paclitaxel and cisplatin (Cam+nab-TP group; n = 132); camrelizumab, paclitaxel and cisplatin (Cam+TP group; n = 130); and paclitaxel with cisplatin (TP group; n = 129), followed by surgical resection. Both the Cam+nab-TP and Cam+TP groups also received adjuvant camrelizumab. The dual primary endpoints were the rate of pathological complete response (pCR), as evaluated by a blind independent review committee, and event-free survival (EFS), as assessed by investigators. This study reports the final analysis of pCR rates. In the intention-to-treat population, the Cam+nab-TP and Cam+TP groups exhibited significantly higher pCR rates of 28.0% and 15.4%, respectively, compared to 4.7% in the TP group (Cam+nab-TP versus TP: difference 23.5%, 95% confidence interval (CI) 15.1-32.0, P < 0.0001; Cam+TP versus TP: difference 10.9%, 95% CI 3.7-18.1, P = 0.0034). The study met its primary endpoint of pCR; however, EFS is not yet mature. The incidence of grade ≥3 treatment-related adverse events during neoadjuvant treatment was 34.1% for the Cam+nab-TP group, 29.2% for the Cam+TP group and 28.8% for the TP group; the postoperative complication rates were 34.2%, 38.8% and 32.0%, respectively. Neoadjuvant camrelizumab plus chemotherapy demonstrated superior pCR rates compared to chemotherapy alone for LA-ESCC, with a tolerable safety profile. Chinese Clinical Trial Registry identifier: ChiCTR2000040034 .

4.
Clin Lab ; 70(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38965969

RESUMO

BACKGROUND: This study aimed to understand the clinical characteristics of pulmonary abscess caused by Streptococcus constellatus infection. METHODS: The clinical manifestations, laboratory examination, drug sensitivity, chest CT manifestations, and treatment and prognosis of patients with pulmonary abscess caused by Streptococcus constellatus infection were retrospectively collected and analyzed. RESULTS: A total of 9 cases of pulmonary abscess caused by Streptococcus constellatus infection were confirmed; one case was confirmed by traditional cultures, while metagenomic next-generation sequencing (mNGS) confirmed the other 8 cases. All of the 9 patients had different degrees of cough, sputum, fever, chest pain, and/or dyspnea, and the physical examination showed fast breathing, reduced respiratory sound, or moist rales on the affected side. In laboratory tests, 8 patients had elevated white blood cells and hypoproteinemia upon admission. Blood gas analysis showed an oxygenation index < 300. The antimicrobial susceptibility testing results in 1 patient with culture-confirmed pathogen diagnosis showed that Streptococcus constellatus was susceptible to ampicillin, penicillin G, cefotaxime, ceftriaxone, cefepime, meropenem, chloramphenicol, linezolid, levofloxacin, and vancomycin and resistant to tetracycline and clindamycin. Relevant antibiotic resistance genes were not detected by mNGS in the 8 patients with negative culture and positive mNGS results. A chest CT showed lung consolidation or cavity formation in 9 patients admitted to the hospital, and 5 patients had pleural effusion. 3 cases were admitted to the respiratory intensive care unit (RICU) and 6 cases were admitted to the general ward. There were 3 cases of nasal catheter oxygen inhalation, 1 case of mask oxygen inhalation, and 5 cases of non-invasive ventilator assisted ventilation. All patients received penicillin or respiratory quinolones anti-infection therapy, and 3 cases were treated with a thoracic closed drainage tube. All patients were discharged from the hospital after improvement, and the hospital stay was 15 - 23 days. CONCLUSIONS: Patients with pulmonary abscess caused by Streptococcus constellatus infection have an urgent condition and rapid progression. It is helpful to use mNGS combined with traditional culture as soon as possible to identify the pathogenic bacteria. Penicillin antibiotics should be the first choice for pulmonary abscess caused by a suspected Streptococcus constellatus infection. If a patient´s condition worsens during the treatment, especially for patients who have lesions involving the interlobar fissure or pleura, compressive atelectasis caused by pleural fluid formation or an increase in the amount of pleural effusion needs to be highly suspected.


Assuntos
Antibacterianos , Abscesso Pulmonar , Infecções Estreptocócicas , Streptococcus constellatus , Humanos , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/tratamento farmacológico , Abscesso Pulmonar/microbiologia , Abscesso Pulmonar/diagnóstico , Abscesso Pulmonar/tratamento farmacológico , Streptococcus constellatus/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Antibacterianos/uso terapêutico , Idoso , Adulto , Testes de Sensibilidade Microbiana , Tomografia Computadorizada por Raios X , Sequenciamento de Nucleotídeos em Larga Escala
5.
Front Microbiol ; 15: 1414203, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38939185

RESUMO

Tetramethylpyrazine (TTMP) is considered a crucial flavor component in Moutai-flavored liquor. Laceyeella sacchari FBKL4.010 (L. sacchari) is the dominant species found in Moutai-flavor Daqu, and this study aims to determine the mechanism by which L. sacchari produces TTMP during liquid fermentation of Moutai-flavor Daqu. The results of the liquid fermentation performance demonstrated a gradual increase in biomass over time, while there was a gradual decline in residual glucose content and pH value. Furthermore, analysis of volatile components revealed that liquid fermentation significantly enhanced the production of TTMP in Moutai-flavor Daqu, with the relative content of TTMP reaching 14.24 mg/L after 96 h of liquid fermentation. Additionally, to explore the synthesis mechanism of TTMP, we compared differentially expressed genes (DEGs) of L. sacchari between 24 and 96 h using comparative transcriptomic techniques. The results indicated that DEGs involved in isoleucine, valine, and leucine biosynthesis pathway were upregulated, while those associated with isoleucine, valine, and leucine degradation pathway were downregulated, suggesting that the valine, leucine, and isoleucine biosynthesis pathway primarily contributes ammonia for TTMP synthesis. The findings of this study present an opportunity for further elucidating the production process of TTMP in Moutai-flavor Daqu during liquid fermentation.

6.
Cancer Cell ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38942026

RESUMO

KRAS G12D is the most frequently mutated oncogenic KRAS subtype in solid tumors and remains undruggable in clinical settings. Here, we developed a high affinity, selective, long-acting, and non-covalent KRAS G12D inhibitor, HRS-4642, with an affinity constant of 0.083 nM. HRS-4642 demonstrated robust efficacy against KRAS G12D-mutant cancers both in vitro and in vivo. Importantly, in a phase 1 clinical trial, HRS-4642 exhibited promising anti-tumor activity in the escalating dosing cohorts. Furthermore, the sensitization and resistance spectrum for HRS-4642 was deciphered through genome-wide CRISPR-Cas9 screening, which unveiled proteasome as a sensitization target. We further observed that the proteasome inhibitor, carfilzomib, improved the anti-tumor efficacy of HRS-4642. Additionally, HRS-4642, either as a single agent or in combination with carfilzomib, reshaped the tumor microenvironment toward an immune-permissive one. In summary, this study provides potential therapies for patients with KRAS G12D-mutant cancers, for whom effective treatments are currently lacking.

7.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(6): 755-762, 2024 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-38918199

RESUMO

Objective: To investigate the physicochemical properties, osteogenic properties, and osteogenic ability in rabbit model of femoral condylar defect of acellular dermal matrix (ADM)/dicalcium phosphate (DCP) composite scaffold. Methods: ADM/DCP composite scaffolds were prepared by microfibril technique, and the acellular effect of ADM/DCP composite scaffolds was detected by DNA residue, fat content, and α-1,3-galactosyle (α-Gal) epitopes; the microstructure of scaffolds was characterized by field emission scanning electron microscopy and mercury porosimetry; X-ray diffraction was used to analyze the change of crystal form of scaffold; the solubility of scaffolds was used to detect the pH value and calcium ion content of the solution; the mineralization experiment in vitro was used to observe the surface mineralization. Twelve healthy male New Zealand white rabbits were selected to prepare the femoral condylar defect models, and the left and right defects were implanted with ADM/DCP composite scaffold (experimental group) and skeletal gold ® artificial bone repair material (control group), respectively. Gross observation was performed at 6 and 12 weeks after operation; Micro-CT was used to detect and quantitatively analyze the related indicators [bone volume (BV), bone volume/tissue volume (BV/TV), bone surface/bone volume (BS/BV), trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular separation (Tb.Sp), bone mineral density (BMD)], and HE staining and Masson staining were performed to observe the repair of bone defects and the maturation of bone matrix. Results: Gross observation showed that the ADM/DCP composite scaffold was a white spongy solid. Compared with ADM, ADM/DCP composite scaffolds showed a significant decrease in DNA residue, fat content, and α-Gal antigen content ( P<0.05). Field emission scanning electron microscopy showed that the ADM/DCP composite scaffold had a porous structure, and DCP particles were attached to the porcine dermal fibers. The porosity of the ADM/DCP composite scaffold was 76.32%±1.63% measured by mercury porosimetry. X-ray diffraction analysis showed that the crystalline phase of DCP in the ADM/DCP composite scaffolds remained intact. Mineralization results in vitro showed that the hydroxyapatite layer of ADM/DCP composite scaffolds was basically mature. The repair experiment of rabbit femoral condyle defect showed that the incision healed completely after operation without callus or osteophyte. Micro-CT showed that bone healing was complete and a large amount of new bone tissue was generated in the defect site of the two groups, and there was no difference in density between the defect site and the surrounding bone tissue, and the osteogenic properties of the two groups were equivalent. There was no significant difference in BV, BV/TV, BS/BV, Tb.Th, Tb.N, and BMD between the two groups ( P>0.05), except that the Tb.Sp in the experimental group was significantly higher than that in the control group ( P<0.05). At 6 and 12 weeks after operation, HE staining and Masson staining showed that the new bone and autogenous bone fused well in both groups, and the bone tissue tended to be mature. Conclusion: The ADM/DCP composite scaffold has good biocompatibility and osteogenic ability similar to the artificial bone material in repairing rabbit femoral condylar defects. It is a new scaffold material with potential in the field of bone repair.


Assuntos
Derme Acelular , Regeneração Óssea , Substitutos Ósseos , Fosfatos de Cálcio , Osteogênese , Engenharia Tecidual , Alicerces Teciduais , Animais , Coelhos , Fosfatos de Cálcio/química , Masculino , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Substitutos Ósseos/química , Materiais Biocompatíveis/química , Fêmur/cirurgia , Microscopia Eletrônica de Varredura , Teste de Materiais
8.
Front Microbiol ; 15: 1357749, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863754

RESUMO

Background: Bariatric and metabolic surgery often leads to significant changes in gut microbiota composition, indicating that changes in gut microbiota after bariatric and metabolic surgery might play a role in ameliorating type 2 diabetes (T2D). However, the effects of single-anastomosis duodenal-ileal bypass with sleeve gastrectomy (SADI-S) on gut microbiota in T2D remain unclear. Objectives: To investigate the effects of SADI-S on gut microbiota and glucose metabolism in T2D rats. Methods: Nineteen T2D rats were randomly divided into the SADI-S group (n = 10) and the sham operation with pair-feeding group (sham-PF, n = 9). Fecal samples were collected to analyze the gut microbiota composition with 16S ribosomal DNA gene sequencing. The fasting blood glucose and glycated hemoglobin were measured to evaluate the effects of SADI-S on glucose metabolism. Results: The Chao and ACE index results indicated the richness of the gut microbial community. The ACE and Chao index values were significantly lower in the SADI-S group than in the sham-PF group, indicating that indicating that species richness was significantly lower in the SADI-S group than in the sham-PF group (p < 0.05). Shannon and Simpson indices were used to estimate the species diversity of the gut microbiota. Compared with the sham-PF group, the SADI-S group showed significantly lower Shannon index and higher Simpson index values, indicating that the species diversity was significantly lower in the SADI-S group than in the sham-PF group (p < 0.05). At the genus level, SADI-S significantly changed the abundances of 33 bacteria, including the increased anti-inflammatory bacteria (Akkermansia and Bifidobacterium) and decreased pro-inflammatory bacteria (Bacteroides). SADI-S significantly decreased the fasting blood glucose and glycated hemoglobin levels. The blood glucose level of rats was positively correlated with the relative abundances of 12 bacteria, including Bacteroides, and negatively correlated with the relative abundances of seven bacteria, including Bifidobacterium. Conclusion: SADI-S significantly altered the gut microbiota composition of T2D rats, including the increased anti-inflammatory bacteria (Akkermansia and Bifidobacterium) and decreased pro-inflammatory bacteria (Bacteroides). The blood glucose level of rats was positively correlated with the abundances of 12 bacteria, including Bacteroides, but negatively correlated with the relative abundance of 7 bacteria, including Bifidobacterium. These alternations in gut microbiota may be the mechanism through which SADI-S improved T2D. More studies should be performed in the future to validate these effects.

9.
BMC Infect Dis ; 24(1): 578, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862881

RESUMO

BACKGROUND: Tuberculosis (TB) remains a global public health event of great concern, however epidemic data on TB covering entire areas during the special period of the COVID-19 epidemic have rarely been reported. We compared the dissemination and multidrug-resistance patterns of Mycobacterium tuberculosis complex (MTBC) in the main urban area of Luoyang City, China (including six municipal jurisdictions) and nine county and township areas under its jurisdiction, aimed to establish the epidemiology of TB in this region and to provide reference for precision anti-TB in places with similar settings. METHODS: From 2020 to 2022, sputum samples were collected from 18,504 patients with confirmed, suspected and unexcluded TB in 10 designated TB medical institutions. Insertion sequence 6110 was amplified by PCR (rpoB gene detection if necessary) to confirm the presence of MTBC. PCR-positive specimens were analyzed by multicolor melting curve analysis to detect multidrug resistance. RESULTS: Among the 18,504 specimens, 2675 (14.5%) were MTBC positive. The positive rate was higher in the main urban area than in the county and township areas (29.8% vs. 10.9%, p < 0.001). Male, re-treated and smear-positive groups were high-burden carriers of MTBC. Individuals aged > 60 years were the largest group infected with MTBC in the main urban area, compared with individuals aged < 61 years in the county and township areas. The detection of multidrug-resistant TB (MDR-TB) was higher in the main urban area than in the county and township areas (13.9% vs. 7.8%, p < 0.001). In all areas, MDR-TB groups were dominated by males, patients with a history of TB treatment, and patients aged < 61 years. Stratified analysis of MDR-TB epidemiology showed that MDR4 (INH þ RIF þ EMB þ SM) was predominant in the main urban area, while MDR3 (INH þ RIF þ SM) was predominant in the county and township areas. MDR-TB detection rate and epidemiology differed among the county and township areas. CONCLUSIONS: For local TB control, it is necessary to plan more appropriate and accurate prevention and control strategies according to the regional distribution of MTBC infection.


Assuntos
COVID-19 , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , China/epidemiologia , Adulto , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , COVID-19/epidemiologia , Idoso , Adolescente , Adulto Jovem , Farmacorresistência Bacteriana Múltipla/genética , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Criança , Escarro/microbiologia , SARS-CoV-2/genética , SARS-CoV-2/efeitos dos fármacos , Pré-Escolar , Idoso de 80 Anos ou mais , Lactente , Epidemias
10.
Hum Brain Mapp ; 45(8): e26723, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38864296

RESUMO

This study aims to investigate the structural reorganization in the sensorimotor area of the brain in patients with gliomas, distinguishing between those with impaired and unimpaired strength. Using voxel-based morphometry (VBM) and region of interest (ROI) analysis, gray matter volumes (GMV) were compared in the contralesional primary motor gyrus, primary sensory gyrus, premotor area, bilateral supplementary motor area, and medial Brodmann area 8 (BA8). The results revealed that in patients with right hemisphere gliomas, the right medial BA8 volume was significantly larger in the impaired group than in the unimpaired group, with both groups exceeding the volume in 16 healthy controls (HCs). In patients with left hemisphere gliomas, the right supplementary motor area (SMA) was more pronounced in the impaired group compared to the unimpaired group, and both groups were greater than HCs. Additionally, the volumes of the right medial BA8 in both the impaired group were greater than HCs. Contralateral expansions in the gray matter of hand- and trunk-related cortices of the premotor area, precentral gyrus, and postcentral gyrus were observed compared to HCs. Furthermore, a negative correlation was found between hand Medical Research Council (MRC) score and volumes of the contralateral SMA and bilateral medial BA8. Notably, our findings reveal consistent results across both analytical approaches in identifying significant structural reorganizations within the sensorimotor cortex. These consistent findings underscore the adaptive neuroplastic responses to glioma presence, highlighting potential areas of interest for further neurosurgical planning and rehabilitation strategies.


Assuntos
Neoplasias Encefálicas , Lateralidade Funcional , Glioma , Imageamento por Ressonância Magnética , Córtex Sensório-Motor , Humanos , Masculino , Glioma/diagnóstico por imagem , Glioma/patologia , Glioma/fisiopatologia , Feminino , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Adulto , Pessoa de Meia-Idade , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/patologia , Córtex Sensório-Motor/fisiopatologia , Lateralidade Funcional/fisiologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Córtex Motor/diagnóstico por imagem , Córtex Motor/patologia , Córtex Motor/fisiopatologia , Mapeamento Encefálico , Adulto Jovem
11.
Biomed Opt Express ; 15(6): 3795-3806, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38867797

RESUMO

Fast and efficient separation of target samples is crucial for the application of laser-assisted microdissection in the molecular biology research field. Herein, we developed a laser axial scanning microdissection (LASM) system with an 8.6 times extended depth of focus by using an electrically tunable lens. We showed that the ablation quality of silicon wafers at different depths became homogenous after using our system. More importantly, for those uneven biological tissue sections within a height difference of no more than 19.2 µm, we have demonstrated that the targets with a size of microns at arbitrary positions can be dissected efficiently without additional focusing and dissection operations. Besides, dissection experiments on various biological samples with different embedding methods, which were widely adopted in biological experiments, also have shown the feasibility of our system.

12.
Chemosphere ; 362: 142595, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38866330

RESUMO

Hemocytes of freshwater bivalves are an important target model for evaluating copper (Cu) toxicity in vitro, with excess Cu causing adverse responses in these organisms. Despite this, the mechanisms underlying cytotoxicity remain poorly understood. The freshwater bivalve Anodonta woodiana, employed as a model organism in freshwater environments, was utilized in this study. Hemocytes of A. woodiana were exposed to various aqueous Cu treatments (0.001, 0.01, 0.1, 1, and 10 mg/L), and a control group (no Cu added) for 3 h to investigate the cytotoxic mechanisms of Cu. The results showed a significant increase in the production of reactive oxygen species in hemocytes of all Cu exposed groups compared to the control (p < 0.05). Remarkably, Cu treatments disrupted the cellular membrane (p < 0.05) but did not induce significant changes in the stability of the lysosomal membrane. Cu targeted the mitochondria, leading to a reduction in mitochondrial membrane potential. Additionally, all Cu treatments significantly increased the degree of DNA damage (p < 0.05). Cellular damage and a significant decline in cell viability were observed when the Cu exposure concentration reached 0.1, 1, and 10 mg/L (p < 0.05). Our study provides new insights into the cytotoxicity mechanisms triggered by Cu in hemocytes of the freshwater bivalve A. woodiana, even under environmentally relevant conditions of 0.01 mg/L exposure.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38907064

RESUMO

Ozone pollution is formed through complex chemical and physical processes closely associated with emissions, photochemical reactions, and meteorological conditions. The objective of this study is to quantify the contributions of meteorological chemical formation, vertical transport, and horizontal transport to air quality during spring and summer in different regions of the Sichuan Basin. The Community Multi-scale Air Quality (CMAQ) with the Integrated Process Rate (IPR) was employed to simulate the months of April and July 2021 in the Sichuan Basin. The results indicate that both the spring and summer chemical formation of ozone in the urban centre show negative values, while the surrounding urban areas contribute positively, with chemical formation ranging from 0 to 10 µg·m-3. The maximum ozone level due to horizontal transport in the urban centre exceeds 20 µg·m-3, whereas horizontal transport in the surrounding urban areas exhibits negative values, with transport contributions concentrated within the range of -5 to 0 µg·m-3. The vertical transport in the central and southern parts of the basin shows positive values, with transport contributions ranging from 0 to 10 µg·m-3, and the urban centre exhibits relatively stronger vertical transport with contributions ranging from 10 to 20 µg·m-3. Although the chemical formation contribution in the urban centre is relatively small due to high nitrogen oxide emissions, vertical and horizontal transport play significant roles and are among the key factors contributing to ozone pollution formation.

14.
J Am Chem Soc ; 146(25): 17140-17149, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864776

RESUMO

Enantioselective three-component difunctionalization of alkenes with boron reagents represents an attractive strategy for assembling three-dimensional chiral organoboron compounds. However, regio- and enantiocontrol comprise the pivot challenges in these transformations, which predominantly require the use of activated conjugated alkenes. Herein, by utilizing various carbonyl directing groups, including amides, sulfinamides, ketones, and esters, we succeed in realizing a nickel-catalyzed 1,2-borylalkynylation of unactivated alkenes to enable the simultaneous incorporation of a boron entity and an sp-fragment across the double bond. The products contain boryl, alkynyl, and carbonyl functional groups with orthogonal synthetic reactivities, offering three handles for further derivatization to access valuable intermediates. The utility of this ligand-enabled asymmetric protocol has been highlighted through the late-stage decoration of drug-relevant molecules.

15.
Sci Total Environ ; 942: 173812, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857795

RESUMO

Prenatal exposures to toxic metals and trace elements have been linked to childhood neurodevelopment. However, existing evidence remains inconclusive, and further research is needed to investigate the mixture effects of multiple metal exposures on childhood neurodevelopment. We aimed to examine the associations between prenatal exposure to specific metals and metal mixtures and neurodevelopment in children. In this prospective cohort study, we used the multivariable linear regressions and the robust modified Poisson regressions to explore the associations of prenatal exposure to 25 specific metals with neurodevelopment among children at 3 years of age in 854 mother-child pairs from the Jiangsu Birth Cohort (JBC) Study. The Bayesian kernel machine regression (BKMR) was employed to assess the joint effects of multiple metals on neurodevelopment. Prenatal manganese (Mn) exposure was negatively associated with the risk of non-optimal cognition development of children, while vanadium (V), copper (Cu), zinc (Zn), antimony (Sb), cerium (Ce) and uranium (U) exposures were positively associated with the risk of non-optimal gross motor development. BKMR identified an interaction effect between Sb and Ce on non-optimal gross motor development. Additionally, an element risk score (ERS), representing the mixture effect of multiple metal exposures including V, Cu, Zn, Sb, Ce and U was constructed based on weights from a Poisson regression model. Children with ERS in the highest tertile had higher probability of non-optimal gross motor development (RR = 2.37, 95 % CI: 1.15, 4.86) versus those at the lowest tertile. Notably, Sb [conditional-posterior inclusion probabilities (cPIP) = 0.511] and U (cPIP = 0.386) mainly contributed to the increased risk of non-optimal gross motor development. The findings highlight the importance of paying attention to the joint effects of multiple metals on children's neurodevelopment. The ERS score may serve as an indicator of comprehensive metal exposure risk for children's neurodevelopment.


Assuntos
Desenvolvimento Infantil , Exposição Materna , Metais , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Gravidez , Pré-Escolar , Estudos Prospectivos , Desenvolvimento Infantil/efeitos dos fármacos , Metais/toxicidade , Masculino , Exposição Materna/estatística & dados numéricos , Exposição Materna/efeitos adversos , Poluentes Ambientais/toxicidade , Coorte de Nascimento , China/epidemiologia
16.
Glia ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38899731

RESUMO

Spinal cord injury (SCI) can result in severe motor and sensory deficits, for which currently no effective cure exists. The pathological process underlying this injury is extremely complex and involves many cell types in the central nervous system. In this study, we have uncovered a novel function for macrophage G protein-coupled receptor kinase-interactor 1 (GIT1) in promoting remyelination and functional repair after SCI. Using GIT1flox/flox Lyz2-Cre (GIT1 CKO) mice, we identified that GIT1 deficiency in macrophages led to an increased generation of tumor necrosis factor-alpha (TNFα), reduced proportion of mature oligodendrocytes (mOLs), impaired remyelination, and compromised functional recovery in vivo. These effects in GIT1 CKO mice were reversed with the administration of soluble TNF inhibitor. Moreover, bone marrow transplantation from GIT1 CWT mice reversed adverse outcomes in GIT1 CKO mice, further indicating the role of macrophage GIT1 in modulating spinal cord injury repair. Our in vitro experiments showed that macrophage GIT1 plays a critical role in secreting TNFα and influences the differentiation of oligodendrocyte precursor cells (OPCs) after stimulation with myelin debris. Collectively, our data uncovered a new role of macrophage GIT1 in regulating the transformation of OPCs into mOLs, essential for functional remyelination after SCI, suggesting that macrophage GIT1 could be a promising treatment target of SCI.

17.
Ecotoxicol Environ Saf ; 280: 116548, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850705

RESUMO

Podophyllotoxin (PPT) is a lignan derived from the roots and stems of the Podophyllum plant. However, its enterotoxicity restricts its clinical application. The underlying mechanisms by which PPT exerts its action remain largely elusive. This study aimed to evaluate the molecular mechanisms underlying PPT-induced enterotoxicity utilizing the concept of toxicological evidence chain. Changes in body weight, behavior, and histopathological and biochemical markers in rats were observed. Additionally, microbiome, metabolome, and transcriptome analyses were integrated to identify potential microorganisms, metabolic markers, and major pathways using a co-occurrence network. Our findings suggested that PPT induced pathological changes in rats, including weight loss, diarrhea, and inflammation accompanied by increased levels of IFN-γ, IL-5, IL-6, GRO/KC, and IL-12p70. The decrease in butyrate levels in the PPT group may be related to the enrichment of Firmicutes. The reduction of butyrate levels may impair the expression of PPARγ, subsequently promoting Escherichia-Shigella proliferation. Additionally, the suppression of PPARs pathway may result in the increased production of inflammatory factors, contributing to enterotoxicity. This study offers a novel understanding of the molecular mechanisms underlying PPT-induced enterotoxicity, making a significant contribution to developing strategies to mitigate PPT toxicity and prevent associated diseases.


Assuntos
Podofilotoxina , Animais , Podofilotoxina/toxicidade , Ratos , Masculino , Microbioma Gastrointestinal/efeitos dos fármacos , Ratos Sprague-Dawley , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , PPAR gama/metabolismo , Microbiota/efeitos dos fármacos
18.
Phytomedicine ; 130: 155767, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38833789

RESUMO

BACKGROUND: Due to its high incidence and elevated mortality, hepatocellular carcinoma (HCC) has emerged as a formidable global healthcare challenge. The intricate interplay between gender-specific disparities in both incidence and clinical outcomes has prompted a progressive recognition of the substantial influence exerted by estrogen and its corresponding receptors (ERs) upon HCC pathogenesis. Estrogen replacement therapy (ERT) emerged for the treatment of HCC by administering exogenous estrogen. However, the powerful side effects of estrogen, including the promotion of breast cancer and infertility, hinder the further application of ERT. Identifying effective therapeutic targets for estrogen and screening bioactive ingredients without E2-like side effects is of great significance for optimizing HCC ERT. METHODS: In this study, we employed an integrative approach, harnessing data from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, clinical paraffin sections, adenoviral constructs as well as in vivo studies, to unveil the association between estrogen, estrogen receptor α (ESR1) and HCC. Leveraging methodologies encompassing molecular dynamics simulation and cellular thermal shift assay (CETSA) were used to confirm whether ESR1 is a molecular target of DHT. Multiple in vitro and in vivo experiments were used to identify whether i) ESR1 is a crucial gene that promotes DNA double-strand breaks (DSBs) and proliferation inhibition in HCC, ii) Dihydrotanshinone I (DHT), a quinonoid monomeric constituent derived from Salvia miltiorrhiza (Dan shen) exerts anti-HCC effects by regulating ESR1 and subsequent DSBs, iii) DHT has the potential to replace E2. RESULTS: DHT could target ESR1 and upregulate its expression in a concentration-dependent manner. This, in turn, leads to the downregulation of breast cancer type 1 susceptibility protein (BRCA1), a pivotal protein involved in the homologous recombination repair (HRR) process. The consequence of this downregulation is manifested through the induction of DSBs in HCC, subsequently precipitating a cascade of downstream events, including apoptosis and cell cycle arrest. Of particular significance is the comparative assessment of DHT and isodose estradiol treatments, which underscores DHT's excellent HCC-suppressive efficacy without concomitant perturbation of endogenous sex hormone homeostasis. CONCLUSION: Our findings not only confirm ESR1 as a therapeutic target in HCC management but also underscores DHT's role in upregulating ESR1 expression, thereby impeding the proliferation and invasive tendencies of HCC. In addition, we preliminarily identified DHT has the potential to emerge as an agent in optimizing HCC ERT through the substitution of E2.


Assuntos
Carcinoma Hepatocelular , Proliferação de Células , Quebras de DNA de Cadeia Dupla , Receptor alfa de Estrogênio , Neoplasias Hepáticas , Fenantrenos , Carcinoma Hepatocelular/tratamento farmacológico , Receptor alfa de Estrogênio/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Humanos , Proliferação de Células/efeitos dos fármacos , Fenantrenos/farmacologia , Animais , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Linhagem Celular Tumoral , Camundongos Nus , Masculino , Apoptose/efeitos dos fármacos , Camundongos , Células Hep G2 , Furanos , Quinonas
19.
J Hazard Mater ; 474: 134850, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38850947

RESUMO

Titanium dioxide nanoparticles (nTiO2) have been considered a possible carcinogen to humans, but most existing studies have overlooked the role of human enzymes in assessing the genotoxicity of nTiO2. Here, a toxicogenomics-based in vitro genotoxicity assay using a GFP-fused yeast reporter library was employed to elucidate the genotoxic potential and mechanisms of nTiO2. Moreover, two new GFP-fused yeast reporter libraries containing either human CYP1A1 or CYP1A2 genes were constructed by transformation to investigate the potential modulation of nTiO2 genotoxicity in the presence of human CYP enzymes. This study found a lack of appreciable nTiO2 genotoxicity as indicated by the yeast reporter library in the absence of CYP expression but a significantly elevated indication of genotoxicity in either CYP1A1- or CYP1A2-expressing yeast. The intracellular reactive oxygen species (ROS) measurement indicated significantly higher ROS in yeast expressing either enzyme. The detected mitochondrial DNA damage suggested mitochondria as one of the target sites for oxidative damage by nTiO2 in the presence of either one of the CYP enzymes. The results thus indicated that the genotoxicity of nTiO2 was enhanced by human CYP1A1 or CYP1A2 enzyme and was associated with elevated oxidative stress, which suggested that the similar mechanisms could occur in human cells.


Assuntos
Citocromo P-450 CYP1A1 , Dano ao DNA , Testes de Mutagenicidade , Espécies Reativas de Oxigênio , Saccharomyces cerevisiae , Titânio , Humanos , Titânio/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1A2/metabolismo , Mutagênicos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Genes Reporter , Nanopartículas/toxicidade , Nanopartículas Metálicas/toxicidade , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo
20.
Appl Opt ; 63(12): 3174-3177, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856463

RESUMO

This study reports on a composite structure composing tilted taper, and tilted and curved waveguides with the aim of enhancing the spectral width and output power of mid-infrared quantum cascade superluminescent emitters (QC-SLEs). The computational results indicate that a tilt angle of 10° and a curved angle of 20° can avoid the selectivity of a certain wavelength due to interference effects at tilt angles of 6° and 8°, resulting in the minimum reflectivity of 1.3×10-4 and 4.4×10-4 for each wide and narrow cavity surface. Simultaneously, the modes propagating perpendicular to the cavity surface exist the least. The corresponding experimental results show a significant enhancement in the spectral width to 168.5c m -1 and a high power output of 5.1 mW for the device. This study presents what we believe to be a novel concept for the designing of superluminescent emitters with both a broadband and high power output.

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