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It has been shown that exposure to hexavalent Chromium, Cr (â ¥), via nasal cavity can have neurotoxicological effects and induces behavioral impairment due to the fact that blood brain barrier (BBB) does not cover olfactory bulb. But whether Cr (â ¥) can cross the BBB and have a toxicological effects in central nervous system (CNS) remains unclear. Therefore, we investigated the effects of Cr (â ¥) on mice treated with different concentrations and exposure time (14 days and 28 days) of Cr (â ¥) via intraperitoneal injection. Results revealed that Cr accumulated in hypothalamus (HY) in a timely dependent manner. Much more severer neuropathologies was observed in the group of mice exposed to Cr (â ¥) for 28 days than that for 14 days. Gliosis, neuronal morphological abnormalities, synaptic degeneration, BBB disruption and neuronal number loss were observed in HY. In terms of mechanism, the Nrf2 related antioxidant stress signaling dysfunction and activated NF-κB related inflammatory pathway were observed in HY of Cr (â ¥) intoxication mice. And these neuropathologies and signaling defects appeared in a timely dependent manner. Taking together, we proved that Cr (â ¥) can enter HY due to weaker BBB in HY and HY is the most vulnerable CNS region to Cr (â ¥) exposure. The concentration of Cr in HY increased along with time. The accumulated Cr in HY can cause BBB disruption, neuronal morphological abnormalities, synaptic degeneration and gliosis through Nrf2 and NF-κB signaling pathway. This finding improves our understanding of the neurological dysfunctions observed in individuals who have occupational exposure to Cr (â ¥), and provided potential therapeutic targets to treat neurotoxicological pathologies induced by Cr (â ¥).
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Barrera Hematoencefálica , FN-kappa B , Ratones , Animales , Barrera Hematoencefálica/metabolismo , FN-kappa B/metabolismo , Cromo/toxicidad , Gliosis , Factor 2 Relacionado con NF-E2/metabolismo , Modelos Animales de Enfermedad , Hipotálamo/metabolismoRESUMEN
BACKGROUND: Peste des petits ruminants (PPR) disease is a cross-species infectious disease that severely affects small ruminants and causes great losses to livestock industries in various countries. Distinguishing vaccine-immunized animals from naturally infected animals is an important prerequisite for the eradication of PPR. At present PPRV are classified into lineages I through IV, and only one vaccination strain, Nigeria/75/1, belongs to lineage II, but all of the epidemic strains in China at present are from lineage IV. RESULTS: To achieve this goal, we developed an SYBR Green I real-time qRT-PCR method for rapid detection and identification of PPRV lineages II and IV by analyzing different melting curve analyses. The negative amplification of other commonly circulating viruses such as orf virus, goat poxvirus, and foot-and-mouth disease virus demonstrated that primers targeting the L gene of PPRV were extremely specific. The sensitivity of the assay was assessed based on plasmid DNA and the detection limit achieved was 100 copies of PPRV lineages II and IV. CONCLUSION: Since the method has high sensitivity, specificity, and reproducibility, it will be effectively differentiated PPRV lineages II from PPRV lineages IV in PPRV infected animals.
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Enfermedades de las Cabras , Peste de los Pequeños Rumiantes , Virus de la Peste de los Pequeños Rumiantes , Animales , Virus de la Peste de los Pequeños Rumiantes/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Reproducibilidad de los Resultados , Peste de los Pequeños Rumiantes/epidemiología , Rumiantes , Cabras , Enfermedades de las Cabras/epidemiologíaRESUMEN
Several coccoid cyanobacterial strains, morphologically similar to typical characteristics of Chroococcus, from the Qinghai-Tibet Plateau were isolated and characterized using a polyphasic approach including morphological and molecular information. Morphological characteristics, the phylogeny based on 16S rRNA gene, and 16S-23S internal transcribed spacer secondary structures support establishing a novel Chroococcus-like genus, Cryptochroococcus gen. nov., as well as Limnococcus fonticola sp. nov. Limnococcus is phylogenetically included in Chroococcaceae and has irregularly arranged thylakoids. Therefore, it should no longer be a member of Merismopediaceae (Synechococcales). The phylogeny based on the 16S rRNA gene revealed that Chroococcus-associated genera were monophyletic.
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Cianobacterias , Técnicas de Tipificación Bacteriana , Cianobacterias/genética , ADN Bacteriano , Ácidos Grasos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , TibetRESUMEN
Gnaq is a member of G protein family and is rich in brain tissue. It has attracted the attention of many researchers in melanoma due to its high ratio of mutation. We have previously reported that the expression level of Gnaq in the mouse forebrain cortex was significantly decreased with age. Oxidative stress (OS) is the main cause leading to brain aging and related diseases. The roles and mechanisms of Gnaq in antioxidation in the brain have not been fully explored. In the present study, gene recombinant technique and lentivirus transfection technique were used to generate a Gnaq-overexpression cell model (Gnaq-SY5Y) coupled with H2O2 to build an OS model. The viability of cells, concentration of reactive oxygen species (ROS), apoptosis-related proteins (Bcl-2 and Bax), and signal pathways (NF-κB and Erk1/2) were compared between model cells and control cells. Results showed that the antioxidative ability of Gnaq-SY5Y cells was significantly improved. Concomitantly, the ROS level in Gnaq-SY5Y cells was significantly decreased whether the cells were subject to or not to H2O2 treatment. Anti-apoptotic protein Bcl-2 was up-regulated and apoptosis-promoting protein Bax was down-regulated in Gnaq-SY5Y cells after treatment with H2O2. NF-κB and phosphorylated Erk1/2 (p-Erk1/2) was significantly down-regulated in Gnaq-SY5Y cells. H2O2 treatment decreased Gnaq expression but increased NF-κB and p-Erk1/2 expressions in Gnaq-SY5Y cells. It is therefore concluded that Gnaq plays a pivotal role in antioxidation in neural cells. A possible mechanism for this would be that the overexpressed Gnaq inhibits the cellular damaging effect mediated by NF-κB and Erk1/2 signal pathways.
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Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , FN-kappa B/metabolismo , Neuronas/citología , Neuronas/fisiología , Neuroprotección/fisiología , Estrés Oxidativo/fisiología , Apoptosis/fisiología , Línea Celular , Humanos , Especies Reactivas de OxígenoRESUMEN
The microbial communities of plant ecosystems are in relation to plant growing environment, but the alteration in biodiversity of rhizosphere and phyllosphere microbial communities in closed and controlled environments is unknown. The purpose of this study is to analyze the change regularity of microbial communities with wheat plants dependent-cultivated in a closed artificial ecosystem. The microbial community structures in closed-environment treatment plants were investigated by a culture-dependent approach, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), and Illumina Miseq high-throughput sequencing. The results indicated that the number of microbes decreased along with time, and the magnitude of bacteria, fungi, and actinomycetes were 10(7)-10(8), 10(5), and 10(3)-10(4) CFU/g (dry weight), respectively. The analysis of PCR-DGGE and Illumina Miseq revealed that the wheat leaf surface and near-root substrate had different microbial communities at different periods of wheat ecosystem development and showed that the relative highest diversity of microbial communities appeared at late and middle periods of the plant ecosystem, respectively. The results also indicated that the wheat leaf and substrate had different microbial community compositions, and the wheat substrate had higher richness of microbial community than the leaf. Flavobacterium, Pseudomonas, Paenibacillus, Enterobacter, Penicillium, Rhodotorula, Acremonium, and Alternaria were dominant in the wheat leaf samples, and Pedobacter, Flavobacterium, Halomonas, Marinobacter, Salinimicrobium, Lysobacter, Pseudomonas, Halobacillus, Xanthomonas, Acremonium, Monographella, and Penicillium were dominant populations in the wheat near-root substrate samples.
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Bacterias/clasificación , Bacterias/aislamiento & purificación , Biota , Hongos/clasificación , Hongos/aislamiento & purificación , Triticum/microbiología , Bacterias/genética , Electroforesis en Gel de Gradiente Desnaturalizante , Ecosistema , Hongos/genética , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADNRESUMEN
In order to smooth the spectra automatically and reliably, a spectral smoothing algorithm with adaptive multiscale window average (AWMA) is demonstrated. In this method, different positions of the spectra are smoothed by windows of different width, and the width of the windows will directly affect smoothing. The window with inappropriate width may cause excessive denoising (peak distortion or loss) or inadequate denoising (the flat region of the spectra still contains a lot of noise). So, how to get the right width of the window is the key of spectral smoothing. The algorithm optimized the width of windows by an iterative method, and verified whether the width is the best according to statistical Z-test. In order to increase the reliability of the algorithm, a comprehensive comparison of the thresholds of hypothesis according to simulation data of different SNR was performed. When the threshold is set to 1. 1, the denoising effect can be the best. In this work, the AMWA algorithm was tested by simulated spectra and real syectra, and it can automatically adapt to different spectral shape and different noise intensity. A comprehensive comparison of AMWA smoothing, Savitzky-Golay smoothing and moving average smoothing was performed in this paper, and the AMWA algorithm is better than the other two algorithms. Results show that the AMWA algorithm not only has better denoising effect, but also has higher accuracy and fidelity. This method has achieved great effect not only to simulated spectra but also to real spectra.
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The projection algorithm used in mixture analysis to determine whether there is unknown disturbance existing in grey system can not accurately identify different samples and similar samples at the same time when it is used in the identification of drugs, because of the insufficient criteria. In the present study, one of its criteria for whether the size of measurement error of testing sample is at a limited level is improved for whether the size and distribution of measurement error is equal and similar between testing sample and standard sample. By testing 6 kinds of normal drugs (including BAYER Aspirin Enteric-coated Tablets, TYLENOL Acetaminophen Sustained Release Tablets, BAYER Compound Paracetamol Tablets(II), HUAZHONG Compound Vitamin C, HUAZHONG Vitamin B and MADINGLIN Demperidone Tablets) and 3 kinds of similar drugs of aspirin (including BAYER Aspirin Enteric-coated Tablets, Shanghai SINE Aspirin Enteric-coated Tablets and Bamyl Aspirin Effervescent Tablets), it was found that the un-improved projection algorithm directly used in discrimination of drugs shows poor performance with many problems existing, however, the improved projection algorithm can discriminate different drugs and similar drugs with accuracy up to 100%. The improved projection algorithm can be a universal, accurate and reliable automated pharmaceutical identification algorithm and can provide a reference for the study on identification of substance.
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Algoritmos , Química Farmacéutica/métodos , Espectrometría Raman , Acetaminofén/análisis , Aspirina/análisis , ComprimidosRESUMEN
One of the primary challenges in working with adeno-associated virus (AAV) lies in the inherent instability of its inverted terminal repeats (ITRs), which play vital roles in AAV replication, encapsidation, and genome integration. ITRs contain a high GC content and palindromic structure, which occasionally results in truncations and mutations during plasmid amplification in bacterial cells. However, there is no thorough study on how these alterations in ITRs impact the ultimate AAV vector characteristics. To close this gap, we designed ITRs with common variations, including a single B, C, or D region deletion at one end, and dual deletions at both ends of the vector genome. These engineered ITR-carrying plasmids were utilized to generate AAV vectors in HEK293 cells. The crude and purified AAV samples were collected and analyzed for yield, capsid DNA-filled percentage, potency, and ITR integrity. The results show that a single deletion had minor impact on AAV productivity, packaging efficiency, and in vivo potency. However, deletions on both ends, except A, showed significant negative effects on the above characteristics. Our work revealed the role of ITR regions, A, B, C, and D for AAV production and DNA replication, and proposes a new strategy for the quality control of ITR-bearing plasmids and final AAV products.
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Methamphetamine (METH) - induced cognitive impairments may be related to synaptic degeneration at mossy fiber terminals, critical for spatial memory formation in hippocampal circuits. We have previously found METH-induced neurodegeneration in the striatum by increasing the α-synuclein (α-SYN) level. However, whether and how the METH-induced mossy fiber degeneration is also blamed for the abnormal accumulation of α-SYN remains to be elucidated. Chronic METH exposure decreased mossy fiber density but upregulatedα-SYN and phosphorylated TAU (TAU-pSer396) in hippocampal CA3, associated with glial cell overactivation, axonal neuropathies, and memory impairment. Notably, the knockout of the α-SYN gene significantly alleviated the METH-induced mossy fiber degeneration and memory impairment. Meanwhile, the TAU-pSer396 accumulation and glial activation were ameliorated by α-SYN knockout. Our findings suggest an essential role of α-SYN in mediating METH-induced mossy fiber degeneration, providing promising therapeutic and prophylactic targets for METH-related neurodegenerative diseases.
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Metanfetamina , Metanfetamina/toxicidad , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Fibras Musgosas del Hipocampo/metabolismo , Hipocampo/metabolismoRESUMEN
The type V-I CRISPR-Cas system is becoming increasingly more attractive for genome editing. However, natural nucleases of this system often exhibit low efficiency, limiting their application. Here, we used structure-guided rational design and protein engineering to optimize an uncharacterized Cas12i nuclease, Cas12i3. As a result, we developed Cas-SF01, a Cas12i3 variant that exhibits significantly improved gene editing activity in mammalian cells. Cas-SF01 shows comparable or superior editing performance compared to SpCas9 and other Cas12 nucleases. Compared to natural Cas12i3, Cas-SF01 has an expanded PAM range and effectively recognizes NTTN and noncanonical NATN and TTVN PAMs. In addition, we identified an amino acid substitution, D876R, that markedly reduced the off-target effect while maintaining high on-target activity, leading to the development of Cas-SF01HiFi (high-fidelity Cas-SF01). Finally, we show that Cas-SF01 has high gene editing activities in mice and plants. Our results suggest that Cas-SF01 can serve as a robust gene editing platform with high efficiency and specificity for genome editing applications in various organisms.
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Flavonoids are a highly abundant class of secondary metabolites present in plants. Isoflavonoids, in particular, are primarily synthesized in leguminous plants within the subfamily Papilionoideae. Numerous reports have established the favorable role of isoflavonoids in preventing a range of human diseases. Among the isoflavonoid components, glyceollins are synthesized specifically in soybean plants and have displayed promising effects in mitigating the occurrence and progression of breast and ovarian cancers as well as other diseases. Consequently, glyceollins have become a sought-after natural component for promoting women's health. In recent years, extensive research has focused on investigating the molecular mechanism underlying the preventative properties of glyceollins against various diseases. Substantial progress has also been made toward elucidating the biosynthetic pathway of glyceollins and exploring potential regulatory factors. Herein, we provide a review of the research conducted on glyceollins since their discovery five decades ago (1972-2023). We summarize their pharmacological effects, biosynthetic pathways, and advancements in chemical synthesis to enhance our understanding of the molecular mechanisms of their function and the genes involved in their biosynthetic pathway. Such knowledge may facilitate improved glyceollin synthesis and the creation of health products based on glyceollins.
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Aim: To understand the degree of oncology patients' awareness of drug clinical trials and oncology patients' willingness to participate in drug clinical trials and the factors influencing them. Methods: The differences in the relevant variables of patients' willingness to accept clinical trials were analyzed, and a descriptive analysis was done for the measurement data (mean and standard deviation). Pearson's correlation coefficient analysis was used to examine the correlation between willingness and the demographic variables. Stepwise regression analysis was used to explore the influencing factors of patients' willingness to accept clinical trials. Results: There were no statistical differences in age, gender, education level, marital status, place of residence, monthly income, medical payment method, and treatment time (P > 0.05). Patients' willingness to accept drug clinical trials differed in their cognitive degree of clinical drug trials (P = 0.002). Patients' willingness to accept drug clinical trials differed in their experience in clinical trials (P < 0.001). The correlation difference was statistically significant. The willingness to accept drug clinical trials was negatively correlated with treatment time (R = -0.16, P < 0.05) and positively correlated with awareness of clinical trials and whether they had been subjects (R = 0.16 and 0.43, P < 0.05). Multiple regression analysis showed that patients' willingness was directly influenced by age, treatment time, and whether they had been subjects (F = 21.315, P < 0.001). Conclusion: Age, treatment time, and whether they had been subjects were the direct influencing factors of patients' willingness. This study pointed out that hospitals should do a good job in the publicity of clinical trials of new drugs, expand publicity channels, increase publicity efforts, improve the awareness of clinical trials of the masses, and promote the enthusiasm of the masses to participate in clinical trials of drugs.
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Ensayos Clínicos como Asunto , Neoplasias , Participación del Paciente , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/psicologíaRESUMEN
Peste des petits ruminants (PPR) is an acute and highly pathogenic infectious disease caused by peste des petits ruminants virus (PPRV), which can infect goats and sheep and poses a major threat to the small ruminants industry. The innate immune response plays an important role as a line of defense against the virus. The effect of PPRV on the active innate immune response has been described in several studies, with different conclusions. We infected three goat-derived cell lines with PPRV and tested their innate immune response. PPRV proliferated in caprine endometrial epithelial cells (EECs), caprine skin fibroblasts cells (GSFs), and goat fibroblast cells (GFs), and all cells expressed interferon (IFN) by poly (I: C) stimulation. PPRV infection stimulated expression of type I and type III IFN on EECs, and expression of the latter was significantly stronger, but IFN was not stimulated in fibroblasts (GSFs and GFs). Our results suggested that the effect of PPRV on IFN was cell-type specific. Nine IFN-stimulated genes (ISGs) were detected in EECs, but only ISG15 and RSAD2 were significantly upregulated. The effects of PPRV on IFN and IFN-induced ISGs were cell-type specific, which advances our understanding of the innate immune response induced by PPRV and creates new possibilities for the control of PPRV infection.
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Enfermedades de las Cabras , Peste de los Pequeños Rumiantes , Virus de la Peste de los Pequeños Rumiantes , Animales , Antivirales/farmacología , Cabras/genética , Inmunidad Innata , Interferones/farmacología , Peste de los Pequeños Rumiantes/genética , Virus de la Peste de los Pequeños Rumiantes/genética , OvinosRESUMEN
Peste des petits ruminants virus (PPRV) causes a highly contagious disease in small ruminants and severe economic losses in developing countries. PPRV infection can stimulate high levels of interferon (IFN) and many IFN-stimulated genes (ISGs), such as ISG15, which may play a key role in the process of viral infection. However, the role of ISG15 in PPRV infection and replication has not yet been reported. In this study, we found ISG15 expression to be significantly upregulated after PPRV infection of caprine endometrial epithelial cells (EECs), and ISG15 inhibits the proliferation of PPRV. Further analysis showed that free ISG15 could inhibit PPRV proliferation. Moreover, ISG15 does not affect the binding, entry, and transcription but does suppress the replication of PPRV. A detailed analysis revealed that ISG15 interacts and colocalizes with both viral N and P proteins and that its interactive regions are all located in the N-terminal domain. Further studies showed that ISG15 can competitively interact with N and P proteins and significantly interfere with their binding. Finally, through the construction of the C-terminal mutants of ISG15 with different lengths, it was found that amino acids (aa) 77 to 101 play a key role in inhibiting the binding of N and P proteins and that interaction with the P protein disappears after the deletion of 77 to 101 aa. The present study revealed a novel mechanism of ISG15 in disrupting the activity of the N0-P complex to inhibit viral replication. IMPORTANCE PPRV, a widespread and fatal disease of small ruminants, is one of the most devastating animal diseases in Africa, the Middle East, and Asia, causing severe economic losses. IFNs play an important role as a component of natural immunity against pathogens, yet the role of ISG15, an IFN-stimulated gene, in protecting against PPRV infection is currently unknown. We demonstrated, for the first time, that free ISG15 inhibits PPRV proliferation by disrupting the activity of the N0-P complex, a finding that has not been reported in other viruses. Our results provide important insights that can further understand the pathogenesis and innate immune mechanisms of PPRV.
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Peste de los Pequeños Rumiantes , Virus de la Peste de los Pequeños Rumiantes , Animales , Virus de la Peste de los Pequeños Rumiantes/genética , Peste de los Pequeños Rumiantes/metabolismo , Nucleoproteínas , Fosfoproteínas , Cabras , Interferones/genética , Rumiantes , AminoácidosRESUMEN
The cyanotoxin cylindrospermopsin (CYN), a toxic metabolite from cyanobacteria, is of particular concern due to its cosmopolitan occurrence, aquatic bioaccumulation, and multi-organ toxicity. CYN is the second most often recorded cyanotoxin worldwide, and cases of human morbidity and animal mortality are associated with ingestion of CYN contaminated water. The toxin poses a great challenge for drinking water treatment plants and public health authorities. CYN, with the major toxicity manifested in the liver, is cytotoxic, genotoxic, immunotoxic, neurotoxic and may be carcinogenic. Adverse effects are also reported for endocrine and developmental processes. We present a comprehensive review of CYN over the past four decades since its first reported poisoning event, highlighting its global occurrence, biosynthesis, toxicology, removal, and monitoring. In addition, current data gaps are identified, and future directions for CYN research are outlined. This review is beneficial for understanding the ins and outs of this environmental pollutant, and for robustly assessing health hazards posed by CYN exposure to humans and other organisms.
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Alcaloides , Toxinas Bacterianas , Cianobacterias , Animales , Toxinas de Cianobacterias , Humanos , Uracilo/toxicidadRESUMEN
Raphidiopsis raciborskii is a diazotrophic and potentially toxic cyanobacterium. To date, this species has successfully invaded many regions from the tropics to sub-tropical and temperate regions, typically forming blooms at temperatures greater than 25 °C. However, there have been a few cases in which R. raciborskii blooms have occurred at low temperatures (below 15 °C), but its cause and mechanisms remain unclear. In this study, field investigations revealed that R. raciborskii blooms occurred at 10-15 °C in Lake Xihu, Yunnan, China. The biomass of R. raciborskii was found to be positively related to nitrate concentrations in this lake. Three strains of R. raciborskii, two isolated from Lake Xihu (CHAB 6611 and CHAB 6612) and one from Lushui Reservoir in central China (CHAB 3409), were used for growth experiments at 15 °C. The three strains exhibited genotypic (16S rRNA and ITS-L genes) and physiological differences in response to nitrogen concentrations at low temperature. The growth rates of strains CHAB 6611 and CHAB 6612 increased with nitrogen concentration while CHAB 3409 could not grow at 15 °C. Furthermore, the growth and phenotypic responses of CHAB 6611 and CHAB 6612 to nitrogen concentrations were different, despite the closer genetic relationship shared by these two strains. Thus, increased nitrogen concentration in water may enhance the biological availability and utilization of nitrogen by R. raciborskii, which is the external promoter, leading to improving the resistance of R. raciborskii to low temperature. The internal cause is the presence of ecotypes in R. raciborskii populations with adaptation to low temperature. With increasing global eutrophication, the distribution range of R. raciborskii as well as the scale of its blooms will increase. As such, the risk of exposure of aquatic biota and humans to cylindrospermopsin is also expected to increase.
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Ecotipo , Nitrógeno , China , Cylindrospermopsis , Humanos , ARN Ribosómico 16S , TemperaturaRESUMEN
As a successful invasive cyanobacterial species, Raphidiopsis raciborskii is distributed globally and shows a tendency to replace Microcystis aeruginosa in many subtropical and temperate waters, but the ecological traits that contribute to its invasiveness are still unclear. In this study, we found that R. raciborskii occurred in 149 sites in 42 lakes in eastern and central China and coexisted with M. aeruginosa at most sites. Based on field results, a combination of invasion and competition experiments using a biomass gradient to evaluate the invasiveness and competitiveness of R. raciborskii compared with M. aeruginosa was conducted. In invasive groups, both R. raciborskii and M. aeruginosa were shown to have positive specific growth rates, indicating that R. raciborskii could coexist with M. aeruginosa. Furthermore, R. raciborskii was shown to grow faster from invasion while M. aeruginosa reduced growth for invasion. In competitive groups, R. raciborskii reached a higher maximum biomass and grew longer than M. aeruginosa. The specific growth rate of R. raciborskii was not inhibited by M. aeruginosa biomass, whereas the growth of M. aeruginosa was inhibited by R. raciborskii biomass. It was shown during the whole experiment that R. raciborskii tended to replace M. aeruginosa to become dominant owing to its faster growth rate and the eventual decline in growth of M. aeruginosa. With an increase in biomass of M. aeruginosa, the vegetative cell size and filament length of R. raciborskii gradually increased. This study has demonstrated that the inherent invasive traits of R. raciborskii, size differences, niche differences, and relative fitness differences between R. raciborskii and M. aeruginosa are crucial reasons for the invasive success of R. raciborskii. Our results revealed the invasiveness and domination of R. raciborskii from a new perspective.
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Cylindrospermopsis , Microcystis , China , EcologíaRESUMEN
An efficient copper-catalyzed direct 2-arylation of benzoxazoles and benzoimidazoles with aryl bromides is presented. The CuI/PPh3-based catalyst promotes the installation of various aryl and heteroaryl groups through a C-H activation process in good to excellent yields. The cytotoxicity of obtained 2-aryl benzoxazoles (benzoimidazoles) was also evaluated and 1-methyl-2-(naphthalen-1-yl)benzoimidazole showed potential cytotoxicity.
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Benceno/química , Benzoxazoles/química , Bromuros/química , Cobre/química , Imidazoles/química , Benzoxazoles/síntesis química , Benzoxazoles/farmacología , Catálisis , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Células HCT116 , Células Hep G2 , Humanos , Imidazoles/síntesis química , Imidazoles/farmacología , Modelos Químicos , Estructura MolecularRESUMEN
Cell fate commitment of pre-implantation blastocysts, to either the inner cell mass or trophoblast, is the first step in cell lineage segregation of the developing human embryo. However, the intercellular signals that control fate determination of these cells remain obscure. Human embryonic stem cells (hESCs) provide a unique model for studying human early embryonic development. We have previously shown that Activin/Nodal signaling contributes to maintaining pluripotency of hESCs, which are derivatives of the inner cell mass. Here we further demonstrate that the inhibition of Activin/Nodal signaling results in the loss of hESC pluripotency and trophoblast differentiation, similar to BMP4-induced trophoblast differentiation from hESCs. We also show that the trophoblast induction effect of BMP4 correlates with and depends on the inhibition of Activin/Nodal signaling. However, the activation of BMP signaling is still required for trophoblast differentiation when Activin/Nodal signaling is inhibited. These data reveal that the early lineage segregation of hESCs is determined by the combinatorial signals of Activin/Nodal and BMP.