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The emergence and dissemination of antibiotic resistance genes (ARGs) in the ecosystem are global public health concerns. One Health emphasizes the interconnectivity between different habitats and seeks to optimize animal, human, and environmental health. However, information on the dissemination of antibiotic resistance genes (ARGs) within complex microbiomes in natural habitats is scarce. We investigated the prevalence of antibiotic resistant bacteria (ARB) and the spread of ARGs in intensive bullfrog (Rana catesbeiana) farms in the Shantou area of China. Antibiotic susceptibilities of 361 strains, combined with microbiome analyses, revealed Escherichia coli, Edwardsiella tarda, Citrobacter and Klebsiella sp. as prevalent multidrug resistant bacteria on these farms. Whole genome sequencing of 95 ARB identified 250 large plasmids that harbored a wide range of ARGs. Plasmid sequences and sediment metagenomes revealed an abundance of tetA, sul1, and aph(3â³)-Ib ARGs. Notably, antibiotic resistance (against 15 antibiotics) highly correlated with plasmid-borne rather than chromosome-borne ARGs. Based on sequence similarities, most plasmids (62%) fell into 32 distinct groups, indicating a potential for horizontal plasmid transfer (HPT) within the frog farm microbiome. HPT was confirmed in inter- and intra-species conjugation experiments. Furthermore, identical mobile ARGs, flanked by mobile genetic elements (MGEs), were found in different locations on the same plasmid, or on different plasmids residing in the same or different hosts. Our results suggest a synergy between MGEs and HPT to facilitate ARGs dissemination in frog farms. Mining public databases retrieved similar plasmids from different bacterial species found in other environmental niches globally. Our findings underscore the importance of HPT in mediating the spread of ARGs in frog farms and other microbiomes of the ecosystem.
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Bacterias , Transferencia de Gen Horizontal , Plásmidos , Animales , Plásmidos/genética , China , Bacterias/genética , Bacterias/efectos de los fármacos , Antibacterianos/farmacología , Granjas , Farmacorresistencia Bacteriana/genética , Rana catesbeiana/microbiología , Rana catesbeiana/genética , Farmacorresistencia Microbiana/genética , Microbiota/genéticaRESUMEN
Strain sensors that can rapidly and efficiently detect strain distribution and magnitude are crucial for structural health monitoring and human-computer interactions. However, traditional electrical and optical strain sensors make access to structural health information challenging because data conversion is required, and they have intricate, delicate designs. Drawing inspiration from the moisture-responsive coloration of beetle wing sheaths, we propose using Ecoflex as a flexible substrate. This substrate is coated with a Fabry-Perot (F-P) optical structure, comprising a "reflective layer/stretchable interference cavity/reflective layer", creating a dynamic color-changing visual strain sensor. Upon the application of external stress, the flexible interference chamber of the sensor stretches and contracts, prompting a blue-shift in the structural reflection curve and displaying varying colors that correlate with the applied strain. The innovative flexible sensor can be attached to complex-shaped components, enabling the visual detection of structural integrity. This biomimetic visual strain sensor holds significant promise for real-time structural health monitoring applications.
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Sporulating bacteria can retreat into long-lasting dormant spores that preserve the capacity to germinate when propitious. However, how the revival transcriptional program is memorized for years remains elusive. We revealed that in dormant spores, core RNA polymerase (RNAP) resides in a central chromosomal domain, where it remains bound to a subset of intergenic promoter regions. These regions regulate genes encoding for most essential cellular functions, such as rRNAs and tRNAs. Upon awakening, RNAP recruits key transcriptional components, including sigma factor, and progresses to express the adjacent downstream genes. Mutants devoid of spore DNA-compacting proteins exhibit scattered RNAP localization and subsequently disordered firing of gene expression during germination. Accordingly, we propose that the spore chromosome is structured to preserve the transcriptional program by halting RNAP, prepared to execute transcription at the auspicious time. Such a mechanism may sustain long-term transcriptional programs in diverse organisms displaying a quiescent life form.
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Bacillus subtilis , Esporas Bacterianas , Esporas Bacterianas/genética , Esporas Bacterianas/metabolismo , Bacillus subtilis/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Factor sigma/genética , Factor sigma/metabolismo , Regiones Promotoras Genéticas , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismoRESUMEN
Epithelial ovarian cancer (EOC) is a fatal gynecological malignancy with limited therapeutic options. Previous research has demonstrated that Tripterygium glycosides (GTW) can enhance effectiveness of cisplatin (DDP) chemotherapy against EOC. However, the underlying mechanism of GTW alleviating EOC still remains unclear. In this article, an ID8 cell-derived xenograft mouse model was established to evaluate the anti-tumor efficacy of GTW combined with DDP. Consistent with previous findings, the results suggested that GTW combined with DDP can exhibit a stronger tumor suppressive effect than DDP alone. Additionally, GTW was found can further exert gastrointestinal protection against DDP by reducing pathological damage on colon tissue. Secondly, to verify whether gut microbiota play an instrumental role in GTW's anticancer effect, we treated mice models with antibiotic to eliminate gut microbiota. And our experimental results indicated that all drug groups showed a weaker tumor suppressive effect and more severe gastrointestinal damage post antibiotic supplement. At genus level, the relative abundance of Lactobacillus was dramatically diminished by the antibiotic treatment, while combined treatment of GTW and DDP can significantly restore the level. Moreover, we performed Lactobacillus acidophilus transplantation and healthy mice fecal microbiota transplantation experiments to further investigate the link between the anticancer effect of GTW and gut microbiota. Our results suggested that both cisplatin-sensitizing and intestinal barrier-protecting effects of GTW can be recovered to a different extent. In conclusion, our results indicated that GTW is a promising chemosensitization and intestinal barrier repair drug for EOC, and the potential mechanism may corelate with the restoration of the compromised intestinal microbial balance.
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Microbioma Gastrointestinal , Neoplasias Ováricas , Humanos , Ratones , Femenino , Animales , Cisplatino/farmacología , Cisplatino/uso terapéutico , Tripterygium , Glicósidos/farmacología , Glicósidos/uso terapéutico , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Antibacterianos/farmacología , Antibacterianos/uso terapéuticoRESUMEN
Cisplatin resistance is the main cause of postoperative recurrence and difficulty in the treatment of ovarian cancer. It is urgently needed to identify therapeutic drugs with unique functions to overcome the current challenges in the treatment of ovarian cancer. In this study, we found that TG promoted the accumulation of ROS and MDA in A2780/DDP cells and downregulated the expression of key antioxidant molecules. In vivo, the survival rate of tumor-bearing nude mice was prolonged by TG without significant hepatotoxic reaction. The expression of key antioxidant molecules in tumor tissues was consistent with that in vitro. These findings revealed that TG disrupted homeostasis of redox reactions and induced ferroptosis in A2780/DDP cells, thereby enhancing cisplatin chemosensitivity of ovarian cancer. Overall, TG may be a novel potential therapeutic option for reversing resistance to cisplatin chemotherapy.
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Antineoplásicos , Ferroptosis , Neoplasias Ováricas , Animales , Ratones , Humanos , Femenino , Cisplatino/farmacología , Cisplatino/uso terapéutico , Neoplasias Ováricas/patología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Factor 2 Relacionado con NF-E2/metabolismo , Tripterygium , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Línea Celular Tumoral , Ratones Desnudos , Antioxidantes/farmacología , Resistencia a AntineoplásicosRESUMEN
Eu3+-doped GdAlO3 (Eu:GAP) and Gd0.5La0.5AlO3 (Eu:GLAP) perovskite single crystals were successfully grown using the optical floating zone (OFZ) method. The microstructure, optical, photoluminescence (PL) and radioluminescence (under X-ray excitation, XEL) were investigated. Under the PL excitation of 275 nm, obvious emission bands peaking at 556 nm, 592 nm, 617 nm, 625 nm, 655 nm, and 706 nm were demonstrated, which correspond to the 5D0 â 7Fj (j = 0-4) transitions of Eu3+. The grown Eu:GAP single crystal showed a stronger PL intensity compared with that of Eu:GLAP in the red light region. After annealing at 1000 °C for 4 h in weak reductive atmosphere (Ar + 5% H2), a slight redshift and dramatic enhancement of PL and XEL intensity occurred. In addition, Eu:GLAP show a more intense XEL emission than that of Eu:GAP. Considering their different densities, these two kinds of red luminescence phosphors are proposed to be promising in a wide field of X-ray imaging, warm white, or plant lighting, respectively.
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Today solid-state cooling technologies below liquid nitrogen boiling temperature (77 K), crucial to quantum information technology and probing quantum state of matter, are greatly limited due to the lack of good thermoelectric and/or thermomagnetic materials. Here, we report the discovery of colossal Nernst power factor of 3800 × 10-4 W m-1 K-2 under 5 T at 25 K and high Nernst figure-of-merit of 71 × 10-4 K-1 under 5 T at 20 K in topological semimetal NbSb2 single crystals. The observed high thermomagnetic performance is attributed to large Nernst thermopower and longitudinal electrical conductivity, and relatively low transverse thermal conductivity. The large and unsaturated Nernst thermopower is the result of the combination of highly desirable electronic structures of NbSb2 having compensated high mobility electrons and holes near Fermi level and strong phonon-drag effect. This discovery opens an avenue for exploring material option for the solid-state heat pumping below liquid nitrogen temperature.
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Cefapirina , Frío , Conductividad Eléctrica , Electrónica , NitrógenoRESUMEN
Ce3+, Pr3+ co-doped Lu3Al5O12 (Ce, Pr:LuAG) single crystals and ceramics were prepared using the optical floating zone (OFZ) and reactive vacuum sintering methods, respectively. The microstructure, photo- (λex = 450 nm), and radio-luminescence (under X-ray excitation) performance, as well as scintillation light yield (LY, under γ-ray, 137Cs source) of both materials, were investigated and compared. Ce, Pr:LuAG ceramics had an in-line transmittance of approximately 20% in the visible light range, while the analogous crystals were more transparent (~65%). The X-ray excited luminescent (XEL) spectra showed the characteristic Ce 3+ and Pr3+ emissions located at 310 nm, 380 nm, and 510 nm. The highest LY of the Ce, Pr:LuAG ceramics reached 34,112 pho/MeV at 2 µs time gate, which is higher than that of a single crystal. The ratio of LY values (LY2/LY0.75) between shaping times of 0.75 µs and 2 µs indicated a faster scintillation decay of ceramics regarding single crystals. It was ascribed to the lower effective concentration of luminescent activators in single crystals because of the coefficient segregation effect.
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Endometriosis (EMS) is a disease characterized by estrogen-dependent, chronic inflammatory, and annoying symptoms, which inflicts about 10% reproductive-age women. The diagnosis of endometriosis mainly depends on pathological examination after surgical resection while the pathogenesis of EMS is not clear enough. Surgical resection and drug therapy (including painkillers and hormone therapy, especially gonadotropin-releasing hormone analogs, GnRH-a) are widely used, but they are expensive and have many side effects. There are few studies on vaginal microorganisms in women with endometriosis. We collected vaginal secretions from women with EMS confirmed by pathology and demonstrated that they were different from that of healthy women by 16s rRNA high-throughput sequencing. Additionally, we established the EMS model in female mice by intraperitoneally injecting fragments from donor mice (3-week growth). Then, the mice were treated with mixed antibiotics (vagina) and NF-κB signaling pathway inhibitors (intraperitoneal injection), respectively. The result suggested that the ectopic lesions were inhibited. In addition, inflammatory cytokines IL-1ß, IL-6, and TNF-α in peritoneal fluid, cell proliferation marker ki-67, and macrophage marker Iba-1 in ectopic lesions decreased significantly from that of mock mice. We also observed similar results as above by vaginal microbiota transplantation (VMT) and subcutaneous injection of leuprorelin acetate (LA, one of GnRH-a) for mice with EMS. These results showed that vaginal use of antibiotics or VMT is helpful to treat endometriosis in mice. However, due to the great difference between human and mouse vaginal microbiota, its mechanism and clinical transformation application still need to be further studied in the future.
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The conduction type of semiconductors is vitally important in many fields (e.g., photovoltaics, transistors, and thermoelectrics), but so far, there is no effective and simple indicator to quickly judge or predict the conduction type of various semiconductors. In this work, based on the relationship between the formation energy of charged defect and the Fermi level, we propose a simple and low-cost strategy for high-throughput screening the potential n-type or p-type semiconductors from the material database by using energy positions of band edges as indicators. As a case study, we validate this strategy in searching potential n-type thermoelectric materials from copper (Cu)-containing metal chalcogenides. A new promising thermoelectric material, CuIn5Se8, with potential intrinsic n-type conduction, is successfully screened from 407 Cu-containing metal chalcogenides and validated in the subsequent experiments. Upon doping iodine in CuIn5Se8, a peak thermoelectric figure of merit zT of 0.84 is obtained at 850 K. Beyond thermoelectrics, the strategy proposed in this study also sheds light on the new material development with desired conduction types in photovoltaics, transistors, and other fields.
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To obtain a deeper understand of the energy transfer mechanism between Ce3+ and Tb3+ ions in the aluminum garnet hosts, (Ce, Tb, Gd)3Ga2Al3O12 (GGAG:Ce, Tb) single crystals grown by the optical floating zone (OFZ) method were investigated systematically in a wide range of Tb3+ doping concentration (1-66 at.%). Among those, crystal with 7 at.% Tb reached a single garnet phase while the crystals with other Tb3+ concentrations are mixed phases of garnet and perovskite. Obvious Ce and Ga loss can be observed by an energy dispersive X-ray spectroscope (EDS) technology. The absorption bands belonging to both Ce3+ and Tb3+ ions can be observed in all crystals. Photoluminescence (PL) spectra show the presence of an efficient energy transfer from the Tb3+ to Ce3+ and the gradually quenching effect with increasing of Tb3+ concentration. GGAG: 1% Ce3+, 7% Tb3+ crystal was found to possess the highest PL intensity under excitation of 450 nm. The maximum light yield (LY) reaches 18,941 pho/MeV. The improved luminescent and scintillation characteristics indicate that the cation engineering of Tb3+ can optimize the photoconversion performance of GGAG:Ce.
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Cervical cancer is the fourth most prevalent cancer type among all malignancies, so it is of great significance to find its actual pathogenesis mechanisms. In the present study, 90 women were enrolled, and high-throughput sequencing technology was firstly used to analyze the vaginal microbiota of healthy women (C group), cervical intraepithelial neoplasia patients (CIN group) and cervical cancer patients (CER group). Our results indicates that compared with C group, a higher HPV infection rate as well as increased Neutrophil ratio and tumor marker squamous cell carcinoma antigen (SCCA) were obtained, and a decrease in Lymphocyte ratio and Hemoglobin were also present. In addition, the cervical cancer showed a strong association with reduced probiotics Lactobacillus, increased pathogens Prevotella spp., Sneathia spp. and Pseudomonas spp. These results prove that the immunological changes generated by the cervical cancer and the vaginal microbiota can interact with each other. However, further study investigating the key bacteria for cervical cancer is still needed, which can be a clue for the diagnosis or treatment of cervical cancer.
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Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Papillomaviridae/genética , TecnologíaRESUMEN
In this work, we report a series of Cu3RTe3 (R = Y, Sm, and Dy) ternary compounds with a trigonal structure (R3Ì ) as a family of new thermoelectric materials. First-principles calculations show that Cu3RTe3 (R = Y, Sm, and Dy) compounds are semiconductors with similar band structures and moderate band gaps (0.69-0.82 eV). The synthesized polycrystalline Cu3RTe3 (R = Y, Sm, and Dy) compounds possess moderate carrier concentrations (0.8-2.2 × 1020 cm-3) and density-of-state effective masses (around 1.1 me), yielding decent electrical transport performance. Furthermore, intrinsically low lattice thermal conductivities, below 1 W m-1 K-1 at 300-900 K, originating from the heavy average atomic masses and large number of atoms in the unit cell, are observed for Cu3RTe3 (R = Y, Sm, and Dy). Finally, Cu3DyTe3 demonstrates a peak dimensionless figure of merit of 0.9 at 900 K, which is among the highest reported for the Cu/Ag-based tellurides.
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Present study characterized five Escherichia coli co-expressing ESBL and MCR-1 recovered from food, food-producing animals, and companion animals in China. Antimicrobial susceptibility tests, conjugation experiments, and plasmid typing were performed. Whole genome sequencing (WGS) was undertaken for all five isolates using either PacBio RS II or Illumina HiSeq 2500 platforms. The cefotaxime and colistin resistance encoded by bla CTX-M and mcr-1 genes, respectively, was transferable by conjugation either together or separately for all five strains. Interestingly, the ESBL and mcr-1 genes could be co-selected by cefotaxime, while the colistin only selected the mcr-1-carrying plasmids during the conjugation experiments. Five E. coli sequence types (ST88, ST93, ST602, ST162, and ST457) were detected. Although diverse plasmid profiles were identified, IncI2, IncFIB, and IncFII plasmid types were predominant. These five clonally unrelated isolates harbored the mcr-1 gene located on similar plasmid backbones, which showed high nucleotide similarity to plasmid pHNSHP45. The mcr-1 gene can be co-transmitted with bla CTX-M genes through IncI2 plasmids with or without ISApl1 in our study. Characterization of these co-existence ESBL and mcr-1 isolates extends our understanding on the dissemination of these resistance markers among bacteria of diverse origins.