RESUMO
Expression of the E3 ligase TRIM21 is increased in a broad spectrum of cancers; however, the functionally relevant molecular pathway targeted by TRIM21 overexpression remains largely unknown. Here, we show that TRIM21 directly interacts with and ubiquitinates CLASPIN, a mediator for ATR-dependent CHK1 activation. TRIM21-mediated K63-linked ubiquitination of CLASPIN counteracts the K6-linked ubiquitination of CLASPIN which is essential for its interaction with TIPIN and subsequent chromatin loading. We further show that overexpression of TRIM21, but not a TRIM21 catalytically inactive mutant, compromises CHK1 activation, leading to replication fork instability and tumorigenesis. Our findings demonstrate that TRIM21 suppresses CHK1 activation by preferentially targeting CLASPIN for K63-linked ubiquitination, providing a potential target for cancer therapy.
Assuntos
Replicação do DNA , Proteínas Quinases , Proteínas de Ciclo Celular/metabolismo , Quinase 1 do Ponto de Checagem/genética , Quinase 1 do Ponto de Checagem/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , UbiquitinaçãoRESUMO
Clostridioides difficile is the predominant pathogen responsible for antimicrobial associated diarrhea (AAD) and health care facility-associated infectious diarrhea. The role of C. difficile in China and its impact on public health have gained attention in recent years. Most clinical C. difficile isolates in China belong to multilocus sequence type clade 1 with sequence types (STs) 3, 35 and 54 predominating. Of note, the proportion of C. difficile isolates from clade 4, especially ST37 (PCR ribotype 17), is much higher in China than in other areas. In China, the antimicrobial-resistance profile of C. difficile is similar to that of other countries, demonstrating a higher resistance rate to erythromycin, clindamycin, and fluoroquinolones (ciprofloxacin, levofloxacin, and moxifloxacin). In general, susceptibility to vancomycin and metronidazole of clinical C. difficile in China is high, however, some resistance to metronidazole have recently been reported. Preclinical research on C. difficile in animals in China is limited, and different studies have reported varied isolation rates and antimicrobial resistance profiles. The diverse molecular types of C. difficile in China merit further epidemiological, genomic and evolutionary investigation. While the use of probiotics in preventing C. difficile infection (CDI) have received both support and opposition, the discovery of new probiotics and new formulations are showing promising results in combating the threat posed by CDI.
Assuntos
Anti-Infecciosos , Clostridioides difficile , Infecções por Clostridium , Infecção Hospitalar , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , China/epidemiologia , Clostridioides difficile/genética , Infecções por Clostridium/tratamento farmacológico , Infecções por Clostridium/epidemiologia , Infecção Hospitalar/tratamento farmacológico , Diarreia/tratamento farmacológico , Farmacorresistência Bacteriana/genética , Humanos , Metronidazol/farmacologia , Metronidazol/uso terapêutico , Testes de Sensibilidade Microbiana , RibotipagemRESUMO
The slope-gully system, the erosion unit on the Loess Plateau, suffers from severe soil erosion and loss of soil nutrients. Restoring vegetation can effectively reduce soil erosion, thereby reducing the loss of nitrogen and phosphorus. In the Loess Plateau, owing to the shortage of water resources and the adverse effects of over-revegetation, the restoration of vegetation in large areas is limited. To efficiently prevent the loss of soil nutrients and reduce non-point source pollution, vegetation patterns need to be reasonably restored. However, it is currently not clear as to how this can be achieved. Different slope-gully systems were established in this study, including pattern A (no vegetation), pattern B (up-slope vegetation), pattern C (middle-slope vegetation), and pattern D (down-slope vegetation). Then, the effects of vegetation patterns on soil total nitrogen (TN) and soil total phosphorus (TP) losses associated with runoff and sediment processes was quantitatively evaluated through the simulated rainfall. The results showed that (1) vegetation pattern markedly affected the yields of runoff, sediment, soil nitrogen, and soil phosphorus, resulting in the following order: pattern A > pattern B > pattern C > pattern D. (2) The correlation between TN and runoff was higher than that between TN and sediment; conversely, TP was more strongly correlated with sediment than with runoff. (3) Nitrogen loss with runoff was the main source of TN (58.76-90.74%), while phosphorus loss with sediment was the main source of TP (48.51-89.30%). Compared with other vegetation patterns, the down-slope can more effectively reduce the yields of runoff and sediment, thereby reducing the loss of TN and TP. Therefore, it was suggested that the lower part of the slope should be considered when revegetating.
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Fósforo , Solo , Fósforo/análise , Nitrogênio/análise , Monitoramento Ambiental/métodos , ChinaRESUMO
Carbon black nanoparticles (CBNPs) are one of the most frequently used nanoparticles. Exposure to CBNPs during pregnancy (PrE to CBNPs) can directly induce inflammation, lung injury, and genotoxicity in dams and results in abnormalities in offspring. However, whether exposure to CBNPs during pregnancy enhances the susceptibility of offspring to environmental stimuli remains unknown. To address this issue, in this study, we intranasally treated pregnant mice with mock or CBNPs from gestational day (GD) 9 to GD18, and F1 and F2 offspring were normally obtained. By intratracheal instillation of mice with lipopolysaccharide (LPS) to trigger a classic animal model for acute lung injury, we intriguingly found that after LPS treatment, F1 and F2 offspring after exposure during pregnancy to CBNPs both exhibited more pronounced lung injury symptoms, including more degenerative histopathological changes, vascular leakage, elevated MPO activity, and activation of inflammation-related signaling transduction, compared with F1 and F2 offspring in the mock group, suggesting PrE to CBNPs would aggravate LPS-induced lung injury in offspring, and this effect was intergenerational. We also observed that PrE to CBNPs upregulated the mRNA expression of DNA methyltransferases (Dnmt) 1/3a/3b and DNA hypermethylation in both F1 and F2 offspring, which might partially account for the intergenerational effect. Together, our study demonstrates for the first time that PrE to CBNPs can enhance sensitivity to LPS in both F1 and F2 offspring, and this intergenerational effect may be related to DNA hypermethylation caused by CBNPs.
Assuntos
Dano ao DNA/efeitos dos fármacos , Lesão Pulmonar/induzido quimicamente , Nanopartículas/toxicidade , Efeitos Tardios da Exposição Pré-Natal/patologia , Animais , Feminino , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Gravidez , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismoRESUMO
Alkaliptosis is a recently discovered form of regulated cell death driven by intracellular alkalization. However, the immune characteristics and mechanisms of alkaliptosis are still poorly understood. Here, we show that HMGB1, a multifunctional alarm protein that drives innate immunity, is necessary for inflammation caused by alkaliptotic damage. During alkaliptosis, HMGB1 translocation and release from the nucleus to the cytoplasm to the extracellular space requires nuclear DNA damage signals, whereas the FANCD2-dependent (but not ATM-mediated) DNA repair pathway inhibits this process. Once released by alkaliptotic cancer cells, extracellular HMGB1 binds to the AGER receptor in macrophages and then activates the STING1 pathway to produce pro-inflammatory cytokines (e.g., TNF and IL6). Consequently, the pharmacological or genetic inhibition of the HMGB1-AGER-STING1 pathway limits cytokine production during alkaliptosis. These findings provide new insight into the sterile inflammatory response to cell death.
Assuntos
Proteína HMGB1/metabolismo , Proteínas de Membrana/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Morte Celular Regulada , Animais , Linhagem Celular , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Humanos , Quinase I-kappa B/metabolismo , Mediadores da Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos Knockout , Transdução de SinaisRESUMO
Nonsense-mediated mRNA decay (NMD) is a quality control mechanism that plays an integral role in eliminating abnormal mRNA and corresponding proteins. It is unclear whether the NMD pathway is involved in regulating ferroptosis, which is a type of iron-dependent cell death mainly caused by the inhibition of the antioxidant SLC7A11-GPX4 axis. In this study, we conducted a small-scale RNAi screen and proved that SMG9, a component of the NMD machinery, is a selective driver for ferroptosis in human cancer cells. SMG9 positively regulates ferroptosis independent of its activity in NMD. Instead, SMG9 is a direct binding protein of GPX4 to promote the degradation of GPX4 in response to RSL3 (a GPX4 inhibitor), but not erastin (a SLC7A11 inhibitor). The genetic inhibition of SMG9 increases the accumulation of GPX4 in the mitochondria, thereby preventing mitochondrial oxidative damage, and ultimately favoring ferroptosis resistance in vitro or in xenograft mouse models. Overall, these findings establish a new mitochondrial regulation mechanism that can affect ferroptosis-mediated tumor suppression.
Assuntos
Ferroptose , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Camundongos Nus , ProteóliseRESUMO
In regulated cell death, genetically encoded molecular machinery destroys cells. This process is not only essential for organ development and homeostasis, but also leads to pathological diseases. One form of regulated cell death is ferroptosis, which is an iron-dependent oxidative cell death caused by lipid peroxidation. Although inducing ferroptosis is an emerging anticancer strategy, the molecular mechanism underlying tumor resistance to ferroptotic cell death is still unclear. Here, we show that pirin (PIR), an iron-binding nuclear protein, plays a previously unrecognized role in mediating ferroptosis resistance in human pancreatic cancer cells. The transcription factor NFE2L2 mediates the upregulation of PIR during ferroptosis caused by small-molecule compounds (e.g., erastin or RSL3). PIR is a nuclear redox sensor and regulator, and increasing it limits the oxidative damage of DNA and the subsequent cytoplasmic transport and extracellular release of HMGB1. In contrast, the depletion of PIR initiates HMGB1-dependent autophagy by binding to BECN1, and subsequently promotes ferroptosis by activating ACSL4. Consequently, in cell cultures and xenograft mouse models, blocking PIR signaling enhances ferroptosis-mediated tumor growth suppression. Together, these findings provide new insights into the molecular mechanisms of autophagy-dependent ferroptosis.
Assuntos
Autofagia , Núcleo Celular/metabolismo , Dioxigenases/metabolismo , Ferroptose , Animais , Linhagem Celular Tumoral , Coenzima A Ligases/metabolismo , Dioxigenases/genética , Proteína HMGB1/metabolismo , Humanos , Camundongos Nus , Fator 2 Relacionado a NF-E2/metabolismo , Oxirredução , Regulação para Cima/genéticaRESUMO
Dendritic cells (DCs) are antigen-presenting cells of the immune system, which play a key role in antitumor immunity by activating cytotoxic T cells. Here, we report that elevated ferroptosis, a lipid peroxidation-mediated cell death, impairs the maturation of DCs and their function in tumor suppression. Ferroptosis is selectively induced in DCs by the GXP4 inhibitor RSL3, but not the SLC7A11 inhibitor erastin. Ferroptotic DCs lose their ability to secrete pro-inflammatory cytokines (TNF and IL6) and express MHC class I in response to the maturation signal of lipopolysaccharide. Moreover, ferroptotic DCs fail to induce CD8+ T cells to produce IFNG/IFNγ. Mechanistically, PPARG/PPARγ, a nuclear receptor involved in the regulation of lipid metabolism, is responsible for RSL3-induced ferroptosis in DCs. Consequently, the genetic depletion of PPARG restores the maturation and function of DCs. Using immunogenic cell death-based DC vaccine models, we further demonstrate that PPARG-mediated ferroptosis of DCs limits antitumor immunity in mice. Together, these findings demonstrate a novel role of ferroptotic DCs in driving an immunosuppressive tumor microenvironment.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Imunoterapia/métodos , PPAR gama/imunologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/imunologia , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Ferroptose/imunologia , Peroxidação de Lipídeos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , PPAR gama/genética , PPAR gama/metabolismo , Neoplasias Pancreáticas/metabolismoRESUMO
OBJECTIVE: We focus on providing the first comprehensive national dataset on the incidence, injury aetiology and mortality of TSCI in China. METHODS: A multi-stage stratified cluster sampling method was used. We included TSCI cases from all hospitals in three regions, nine provinces and 27 cities in China via search of electronic medical records and retrospectively analysed the characteristics of TSCI in China from 2009 to 2018. We estimated the incidence of TSCI in the total population and subgroups. RESULTS: There were 5954 actual cases in 2009, corresponding to a total estimated TSCI incidence of 45.1 cases per million population (95% CI, 44.0-46.3). There were 10,074 actual cases in 2018, corresponding to a total estimated TSCI incidence of 66.5 cases per million population (95% CI, 65.2-67.8) (P < 0.001; annual average percentage change (AAPC), 4.4%). From 2009 to 2018, the incidence of almost all sex/age groups showed an increasing trend over time (P < 0.001; AAPC, 0.7-8.8%). The elderly population (aged 65-74) displayed the highest incidence of TSCI (with an average annual incidence of 127.1 cases per million [95% CI, 119.8-134.3]). CONCLUSIONS: The TSCI incidence increased significantly from 2009 to 2018. The incidence in the elderly populations was consistently high and continues to increase over time. The mortality of TSCI patients in hospitals is relatively low and continues to decrease each year, but elderly individuals remain at a high risk of hospital death.
Assuntos
Traumatismos da Medula Espinal , Idoso , China/epidemiologia , Humanos , Incidência , Projetos de Pesquisa , Estudos Retrospectivos , Traumatismos da Medula Espinal/epidemiologiaRESUMO
STUDY DESIGN: A hospital-based retrospective epidemiological study. OBJECTIVE: To describe the demographic and epidemiological characteristics of patients with traumatic spinal cord injury (TSCI) in Xi'an to help health-related institutions formulate corresponding measures. SETTING: People with TSCI, all spine centres and orthopaedic centres in Xi'an, China. METHODS: We retrospectively reviewed the medical records of the all spine centers or orthopedic centers in Xi'an according to the International Classification of Disease Version 10 (ICD-10) and diagnostic code of TSCI. Variables included gender, age, medical insurance, etiology, occupation, level of injury, and severity of injury, multiple injury, complication, treatment, and so on. RESULTS: The study included the medical records of 1730 patients with TSCI from 2014 to 2018. The estimated annual incidence rate increased from 39.0 cases (95% CI, 34.7-43.3 cases) per 1 million persons in 2014 to 43.2 cases (95% CI, 39.0-47.5 cases) per 1 million persons in 2018. The leading cause of TSCI was high falls (35.5%, 614 cases). The most common injury site was the cervical spinal cord, accounting for 55.7% (963 cases). The degree of injury severity with the highest proportion was incomplete tetraplegia (47.2%, 816 cases). In addition, 71.4% (1236 cases) of TSCI cases had spinal fracture or dislocation. CONCLUSIONS: There are specific epidemiological characteristics of TSCI patients in Xi'an, and preventive measures are suggested to be based on the characteristics of the different types of patients with TSCI and focused on high-risk groups.
Assuntos
Traumatismos da Medula Espinal , Acidentes por Quedas , China/epidemiologia , Humanos , Incidência , Estudos Retrospectivos , Traumatismos da Medula Espinal/epidemiologia , Traumatismos da Medula Espinal/etiologiaRESUMO
The risk of heavy metal cadmium (Cd) on aquatic organisms has drawn widespread attentions, but the effects of nanomaterials (e.g. graphene (G)) on Cd toxicity are rarely clarified. It was known that mixture of contaminants may exhibit more severe impact than the individual metal. Here, we conducted a study systematically on the effects of nanomaterials on the toxicity of Cd to Scenedesmus Obliquus (S. obliquus) with or without the presence of graphene family materials (GFMs) derived from G, such as graphene oxide (GO) and amine-modified graphene (GNH). Our results showed that the influence of GFMs on the acute toxicity of Cd to S. obliquus is in the order of GO > G > GNH based on their EC50 of Cd-GFMs. The effects of GFMs on the cytotoxicity and oxidative damage of Cd to S. obliquus are varied with the concentrations of GFMs. The differences between the effects of GFMs on Cd toxicity may attribute to their different surface oxygen-containing functional groups contained in the nanomaterials. The adsorption capacity of nanomaterials on metal ions, their dispersibility in water and their interaction mode with organisms, may dominate main contributions to their effects on Cd toxicity. Our study aids to clarify the interference of nanoparticles on the ecotoxicity of metals, to avoid the misunderstanding of the potential risk of metals in the complicate water environments.
Assuntos
Cádmio/toxicidade , Grafite/química , Nanoestruturas/química , Poluentes Químicos da Água/toxicidade , Adsorção , Organismos Aquáticos , Oxirredução , Scenedesmus/efeitos dos fármacos , Água/químicaRESUMO
Arsenite is a toxic metalloid that may increase the risk of Parkinson's disease by inducing dopaminergic neuronal apoptosis. Luteolin, a common dietary flavonoid, possesses variety of biological functions, but potential effects of luteolin on arsenite toxicity remain elusive. In this study, we demonstrated that luteolin prevented arsenite-induced apoptosis in the dopaminergic PC12 cells. Administration of luteolin to cells attenuated arsenite-induced ROS production, enhanced caspase-3 activity and γ-H2AX expression. Our results further showed the expression of α-Synuclein (α-Syn) was significantly increased in arsenite-treated cells, but co-treatment with luteolin reversed the expression of α-Syn back toward normal level. Inhibition of α-Syn by siRNA remarkably enhanced the beneficial effect of luteolin against arsenite-induced apoptotic cell death. Taken together, these results demonstrate that the ameliorative effects of luteolin against arsenite in the dopaminergic cell may be modulated by α-Syn, and indicating that luteolin may be developed as a chemopreventive supplementary agent to ameliorate dopaminergic cell apoptosis resulting from arsenite exposure.
Assuntos
Apoptose/efeitos dos fármacos , Arsenitos/toxicidade , Dieta , Dopamina/metabolismo , Luteolina/farmacologia , alfa-Sinucleína/antagonistas & inibidores , Animais , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
We unveiled the association of Annexin A7 with vascular endothelial growth factor-C (VEGF-C) and the effect of upregulation of Annexin A7 in Hca-F and Hca-P cells on inhibiting hepatocarcinoma (HCC) lymph node metastasis (LNM) in vitro and in vivo. A total of 200 inbred 615 mice were randomly divided into four equal groups inoculated with Hca-F, Hca-P, FAnxa7-upregulated, and PAnxa7-upregulated cells, respectively. The primary tumor, popliteal, inguinal, and iliac lymph nodes were prepared for immunohistochemical (IHC) staining, real-time quantitative polymerase chain reaction (qRT-PCR) analysis, Western blot, and hematoxylin-eosin (H&E) staining. There was over 50 % increase both in the number of FAnxa7-upregulated and PAnxa7-upregulated cells migrated through the filter compared to their controls (FAnxa7-control, Hca-F and PAnxa7-control, Hca-P). However, no significant differences were noted in invasion ability between them (all P > 0.05). Tumor lymph vessels were significantly reduced in FAnxa7-upregulated and PAnxa7-upregulated tumors when compared with Hca-F and Hca-P tumors (all P < 0.05). Blood vessel density did not differ significantly between FAnxa7-upregulated and PAnxa7-upregulated tumors and Hca-F and Hca-P tumors. Enzyme-linked immunosorbent assay (ELISA) for VEGF-C showed that upregulating Annexin A7 decreased VEGF-C secretion in FAnxa7-upregulated and PAnxa7-upregulated cells (P < 0.05). The IHC staining result showed that the level of serum Annexin A7 was found to be statistically higher in all experimental groups than that in the control group (P < 0.05). The present results indicated that alterations in serum Annexin A7 expression may be of prognostic relevance in HCC lymphatic metastasis.
Assuntos
Anexina A7/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ensaio de Imunoadsorção Enzimática , Feminino , Imuno-Histoquímica , Metástase Linfática , Masculino , Camundongos , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Regulação para Cima , Fator C de Crescimento do Endotélio Vascular/metabolismoRESUMO
The physicochemical properties of Lipu taro starch (LTS), cassava starch (CS) and wheat starch (WS) were analyzed. These starches exhibited a comparable starch content (86 %). However, LTS had a significantly lower amylose content (15.93 %) compared to CS (26.62 %) and WS (33.53 %). Moreover, LTS demonstrated an irregular polygonal cubic morphology with a smaller particle size of 2.55 µm while possessed an A-type crystal structure with high crystallinity at 25.07 %. In contrast, CS and WS had larger particle sizes of 13.33 µm and 16.68 µm, respectively, with lower crystallinities of 22.52 % and 20.33 %. Due to these physicochemical properties, LTS exhibited superior emulsification properties with a higher emulsifying activity index of 8.63 m2/g and an emulsion stability index of 69.18 min, whereas CS and WS had values of 2.35 m2/g and 25.15 min, and 0.37 m2/g and 11.48 min, respectively. LTS also demonstrated enhanced thermal stability, characterized by higher gelatinization temperature (indicated by To, Tp, Tc, and ΔT) and reduced paste viscosity (indicated by PV, TV, FV, SBV, and BDV) compared to CS. However, the mechanical strength of the gel made from LTS (indicated by hardness, adhesiveness, springiness, gumminess, and chewiness) was comparatively inferior to those from CS and WS.
Assuntos
Colocasia , Amido , Amido/química , Colocasia/química , Amilose/química , Tamanho da Partícula , ViscosidadeRESUMO
OBJECTIVE: Multi-segmental thoracolumbar fracture (MSF) generally refers to fractures occurring in two or more segments of the thoracolumbar spine. With the development of minimally invasive concept, there is little research on its application in the field of MSF. The purpose of this study is to compare two minimally invasive surgical techniques and determine which one is more suitable for treating patients with neurologically intact MSF. METHODS: We retrospectively analyzed the clinical data of 49 MSF patients with intact nerves who were admitted from January 2017 to February 2019. Among them, 25 cases underwent percutaneous pedicle screw fixation (PPSF), and 24 cases underwent Wiltse approach pedicle screw fixation (WAPSF). The operation time, number of fixed segments, blood loss, length of incision, postoperative ambulation time, accuracy of pedicle screw placement, facet joint violation (FJV), number of C-arm exposures, as well as pre- and postoperative visual analogue scale (VAS), Oswestry disability index (ODI), local Cobb's angle (LCA), and percentage of anterior vertebral body height (PAVBH) were recorded for both groups. Paired sample t-test was used for intra-group comparison before and after surgery while independent sample t-test was used for inter-group comparison. RESULTS: The differences in the number of fixed segments, intraoperative bleeding, postoperative bed time, accuracy rate of pedicle screw placement, VAS, and ODI between the two groups were not statistically significant (p > 0.05). However, the operative time and total surgical incision length were significantly shorter in the WAPSF group than in the PPSF group (p < 0.05), and the FJV was significantly higher in the PPSF group than in the WAPSF group (p < 0.05). Also, the PPSF group received more intraoperative fluoroscopy (p < 0.05). The result of LCA and PAVBH in the WAPSF group were significantly better than in the PPSF group (p < 0.05). CONCLUSIONS: Both PPSF and WAPSF were found to be safe and effective in the treatment of MSF without neurological deficits through our study. However, considering radiation exposure, FJV, vertebral height restoration, correction of kyphosis, and learning curve, WAPSF may be a better choice for neurologically intact MSF.
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Fraturas Ósseas , Parafusos Pediculares , Fraturas da Coluna Vertebral , Ferida Cirúrgica , Humanos , Fraturas da Coluna Vertebral/cirurgia , Estudos Retrospectivos , Fixação Interna de Fraturas/métodos , Vértebras Torácicas/cirurgia , Vértebras Torácicas/lesões , Vértebras Lombares/cirurgia , Vértebras Lombares/lesões , Resultado do TratamentoRESUMO
This study developed a new single-tube multiplex real-time PCR method for detecting toxigenic C. difficile directly from fecal samples using tcdA, tcdB, cdtB, and internal gene tpi as targets, which could be performed on kinds of polymerase chain reaction device including point-of-care testing (POCT), with improved detection efficiency. The specificity, sensitivity, and repeatability of each gene was evaluated using 69 C. difficile isolates and 74 fecal samples. Results were compared with established PCR, qPCR, and ELISA methods. Interspecies specificity was 100% based on six common intestinal pathogens (Escherichia coli, Enterococcus Faecium, Enterococcus faecalis, Clostridium perfringens, Bacteroides fragilis, Clostridium botulinum). The lower detection limit (LDL) for tcdA, tcdB, and cdtB with pure C. difficile DNA was 101,100, and 100 copies/µL, respectively, the coefficients of variation among different experimental batches and within each experimental batch were both less than 3%, which shows that this method has strong repeatability. And the LDL of fecal DNA was 5 × 100, 5 × 103, and 5 × 102 colony-forming units (CFU)/g, respectively. In addition, the efficiency for detection of tcdA was compared with established PCR and real-time PCR methods, demonstrating high consistency (98.4%) and similar sensitivity. ELISA was used to confirm inconsistent results, which were identical with our method. The sensitivity and specificity for detecting toxigenic C. difficile in fecal samples were 96.49% and 94.12% compared with the toxigenic culture (TC). This method effectively identified the toxigenic and non-toxigenic strains with high specificity, sensitivity, and repeatability, and could reduce the false positive rate of tcdA, and accurately identify the typical Asian strain RT017, making it potentially contribute to the surveillance of CDI in China. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-022-03434-6.
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Stimulus-responsive actuators play a vital role in the new generation of intelligent systems. However, poor mechanical performance, complicated fabrication processes, and the inability to complex deformation limit their practical applications. Herein, these challenges are overcome via designing a strong hygrothermic wood actuator with asymmetric water affinity. The actuator is readily constructed by sandwiching polypyrrole-coated wood with a Ni complex hygroscopic gel top layer for moisture absorption and a polyimide bottom layer as the water barrier. The resulting hygrothermic wood spontaneously stretches and bends itself in response to moisture and thermal/light stimulation. A robotic hand and a series of grippers made of hygrothermic wood demonstrate dexterous object-hand interactions during grasping and holding, while the reversible hygrothermic property allows the actuator to be potentially applied in fire rescue scenarios to rescue trapped objects. A combination of good mechanical properties, multi-stimulus-response, complex deformation, wide working temperature range, low manufacturing cost, and biocompatibility are simultaneously realized by one device. It is thus believed that such a strong wood actuator will open up a new avenue for building intelligent robotic hand systems.
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Background: Increasingly, patient satisfaction after total knee arthroplasty (TKA) is being recognized as an important measure of health-care quality in osteoarthritis (OA) patients. But satisfaction after TKA has not yet been reported in Kashin-Beck disease (KBD). We aim to examine satisfaction and clinical efficacy of TKA in the treatment of OA and KBD. Methods: Retrospectively review of 37 KBD patients (45 knees) and 52 OA patients (58 knees) who underwent TKA from January 2015 to January 2017. Data of outcome measures such as Knee Society knee score (KSKS) and function score (KSFS), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and radiographic evaluation were collected preoperatively and during the last follow-up. Satisfaction was compared using the 2011 Knee Society Scoring System. Results: There were no differences in age, gender, BMI and Follow-up time. KBD patients had significantly worse preoperative range of motion, KSKS, and mechanical lateral distal femoral angle (mLDFA) compared with OA patients (P < 0.05). At the last follow-up, the KSKS, KSFS, WOMAC score, and radiographic parameters of all patients significantly improved (P < 0.05), but the satisfaction was higher in KBD patients than in OA (P < 0.05). Further analysis showed that KSFS, WOMAC total, pain, stiffness, and function scores were significantly worse for KBD (P < 0.05). Conclusion: Patient satisfaction was greater but clinical outcomes were inferior in KBD than in OA. This study also demonstrated that TKA is an effective surgical procedure for KBD, but how to improve functional outcomes needs to be further studied.
Assuntos
Artroplastia do Joelho , Doença de Kashin-Bek , Osteoartrite , Humanos , Doença de Kashin-Bek/cirurgia , Satisfação do Paciente , Estudos Retrospectivos , Satisfação PessoalRESUMO
The extensive application of biochar has drawn more attentions on its potential risk to aquatic organisms. However, the influence of environmental factors (i.e. pH, HA, SDBS and aging time) after they discharged into environment on their toxicity have not been clarified. Here, we synthesized biochar with local pine needles via pyrolysis, and then aged in different media. Followed, the toxicity of pristine and aged biochar was checked with Scenedesmus obliquus (S. obliquus). Our investigation showed that the toxicity of biochar was mitigated when aged in different pH levels or SDBS, while it was opposite in the presence of HA. The increment of pH decreased the toxicity of both the pristine and the aged biochar, while the presence of HA did same impact on the pristine biochar. The presence of SDBS decreased the toxicity of pristine biochar but increased that of aged biochar. Meanwhile, we showed these environmental factors (pH, HA, SDBS and aging time) influenced the biochar toxicity may be due to the adjustment of the aggregation and adhesion of biochar on cell surfaces or the intracellular oxidative stress. Further, the PFRs contained in biochar did influence the toxicity, along with the physicochemical properties of biochar (i.e. carbon structure, functional group or surface charge). Our results aimed to reflect the toxicity profile of biochar in the natural aquatic environment, without misunderstanding of potential ecological risk of biochar in the future application.
Assuntos
Carvão Vegetal , Pirólise , Organismos AquáticosRESUMO
The emergence of multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern threatens the efficacy of currently approved vaccines and authorized therapeutic monoclonal antibodies (MAbs). It is hence important to continue searching for SARS-CoV-2 broadly neutralizing MAbs and defining their epitopes. Here, we isolate 9 neutralizing mouse MAbs raised against the spike protein of a SARS-CoV-2 prototype strain and evaluate their neutralizing potency towards a panel of variants, including B.1.1.7, B.1.351, B.1.617.1, and B.1.617.2. By using a combination of biochemical, virological, and cryo-EM structural analyses, we identify three types of cross-variant neutralizing MAbs, represented by S5D2, S5G2, and S3H3, respectively, and further define their epitopes. S5D2 binds the top lateral edge of the receptor-binding motif within the receptor-binding domain (RBD) with a binding footprint centred around the loop477-489, and efficiently neutralizes all variant pseudoviruses, but the potency against B.1.617.2 was observed to decrease significantly. S5G2 targets the highly conserved RBD core region and exhibits comparable neutralization towards the variant panel. S3H3 binds a previously unreported epitope located within the evolutionarily stable SD1 region and is able to near equally neutralize all of the variants tested. Our work thus defines three distinct cross-variant neutralizing sites on the SARS-CoV-2 spike protein, providing guidance for design and development of broadly effective vaccines and MAb-based therapies.