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Pleurostomatid ciliates, as a highly diverse and widely distributed unicellular eukaryote group, play a crucial role in the cycling of nutrients and energy in microbial food webs. However, research on pleurostomatids remains insufficient, resulting in a paucity of molecular information and substantial gaps in knowledge of their phylogenetic relationships. In recent years, we investigated pleurostomatid diversity in various Chinese habitats, including their systematic relationships and taxonomic circumscriptions, which were comprehensively analyzed using an integrative morphomolecular approach. Results revealed that: (1) pleurostomatids can be categorized into two suborders, Protolitonotina subord. nov. and Amphileptina Jankowski, 1967; (2) Protolitonotina subord. nov. represents the ancestral pleurostomatid group and includes two genera, Protolitonotus and Heterolitonotus gen. nov., characterized by right kineties progressively shortened along rightmost full kineties and absence of a left dorsolateral kinety; (3) Heterolitonotus gen. nov. represents an orphan lineage and is defined by an oral slit extending to its dorsal margin; (4) " Protolitonotus clampi" does not group with congeners but instead represents an orphan lineage, thus Novilitonotus gen. nov. is established to which P. clampi is transferred as Novilitonotus clampi comb. nov.; (5) three new species, Apoamphileptus paraclaparedii sp. nov., Heterolitonotus rex gen. nov., sp. nov., and Loxophyllum apohelus sp. nov., are described; and (6) helices 21es6a to 21es6d within the V4 region of small subunit ribosomal RNA (SSU rRNA) may serve as a useful tool for discriminating pleurostomatids. The evolutionary relationships among all main lineages of pleurostomatids are discussed and a key to the identification of pleurostomatid genera is provided.
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Cilióforos , Filogenia , Especificidad de la Especie , Cilióforos/clasificación , Cilióforos/genética , ChinaRESUMEN
In order to explore the impact of antibiotics (enrofloxacin) on microbial community in aquatic environment, an indoor aquatic ecological model was built, and different concentrations of enrofloxacin (0.05, 0.5, 5, and 50 mg/L) were added in the aquatic ecological model. In addition, the water and sediment samples were collected on the 0, 7, 30, and 60 days, and the changes in microbial community were studied through 16S rDNA high-throughput sequencing. The results showed that when the concentration of enrofloxacin was 50 mg/L, the relative abundance of Actinomycetes was increased. In the water, the bacterial richness and diversity communities first decreased and then gradually recovered with the passage of time; On the 7th day, the diversity and richness index of species in the treatment groups with enrofloxacin at 5 and 50 mg/L decreased to the lowest; On the 30th day, the diversity and richness index of species began to rise; On the 60th day, the diversity index and richness index of water species began to increase, while the diversity index and richness index of sediment species decreased. In conclusion, the addition of enrofloxacin negatively affected the microbial community structure in an indoor aquatic ecological model, 50 mg/L enrofloxacin could increase the relative abundance of Actinomycetes, and decrease the diversity and richness index of water and sediment.
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Temporal lobe epilepsy (TLE) is a chronic neurological disorder that is often resistant to antiepileptic drugs. The pathogenesis of TLE is extremely complicated and remains elusive. Understanding the molecular mechanisms underlying TLE is crucial for its diagnosis and treatment. In the present study, a lithium-pilocarpine-induced TLE model was employed to reveal the pathological changes of hippocampus in rats. Hippocampal samples were taken for proteomic analysis at 2 weeks after the onset of spontaneous seizure (a chronic stage of epileptogenesis). Isobaric tag for relative and absolute quantization (iTRAQ) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique was applied for proteomic analysis of hippocampus. A total of 4173 proteins were identified from the hippocampi of epileptic rats and its control, of which 27 differentially expressed proteins (DEPs) were obtained with a fold change > 1.5 and P < 0.05. Bioinformatics analysis indicated 27 DEPs were mainly enriched in "regulation of synaptic plasticity and structure" and "calmodulin-dependent protein kinase activity," which implicate synaptic remodeling may play a vital role in the pathogenesis of TLE. Consequently, the synaptic plasticity-related proteins and synaptic structure were investigated to verify it. It has been demonstrated that CaMKII-α, CaMKII-ß, and GFAP were significant upregulated coincidently with proteomic analysis in the hippocampus of TLE rats. Moreover, the increased dendritic spines and hippocampal sclerosis further proved that synaptic plasticity involves in the development of TLE. The present study may help to understand the molecular mechanisms underlying epileptogenesis and provide a basis for further studies on synaptic plasticity in TLE.
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Epilepsia del Lóbulo Temporal , Animales , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Cromatografía Liquida , Modelos Animales de Enfermedad , Epilepsia del Lóbulo Temporal/inducido químicamente , Hipocampo/metabolismo , Plasticidad Neuronal , Pilocarpina , Proteómica , Ratas , Espectrometría de Masas en TándemRESUMEN
Heterotrimeric G proteins function as key players in guard cell signaling to many stimuli, including ultraviolet B (UV-B) and ethylene, but whether guard cell G protein signaling is activated by the only one potential G protein-coupled receptor, GCR1, is still unclear. Here, we found that gcr1 null mutants showed defects in UV-B- and ethylene-induced stomatal closure and production of reactive oxygen species (ROS) and nitric oxide (NO) in guard cells, but these defects could be rescued by the application of a Gα activator or overexpression of a constitutively active form of Gα subunit GPA1 (cGPA1). Moreover, the exogenous application of hydrogen peroxide (H2O2) or NO triggered stomatal closure in gcr1 mutants and cGPA1 transgenic plants in the absence or presence of UV-B or ethylene, but exogenous ethylene could not rescue the defect of gcr1 mutants in UV-B-induced stomatal closure, and gcr1 mutants did not affect UV-B-induced ethylene production in Arabidopsis leaves. These results indicate that GCR1 positively controls UV-B- and ethylene-induced stomatal closure by activating GPA1-dependent ROS and NO production in guard cells and that ethylene acts upstream of GCR1 to transduce UV-B guard cell signaling, which establishes the existence of a classic paradigm of G protein signaling in guard cell signaling to UV-B and ethylene.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Etilenos/metabolismo , Etilenos/farmacología , Subunidades alfa de la Proteína de Unión al GTP/metabolismo , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/farmacología , Óxido Nítrico/metabolismo , Estomas de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptores Acoplados a Proteínas G/metabolismoRESUMEN
Background and Purpose: Temporal lobe epilepsy (TLE) is a common chronic neurological disease that is often invulnerable to anti-epileptic drugs. Increasing data have demonstrated that acetylcholine (ACh) and cholinergic neurotransmission are involved in the pathophysiology of epilepsy. Cytisine, a full agonist of α7 nicotinic acetylcholine receptors (α7nAChRs) and a partial agonist of α4ß2nAChRs, has been widely applied for smoking cessation and has shown neuroprotection in neurological diseases. However, whether cytisine plays a role in treating TLE has not yet been determined. Experimental Approach: In this study, cytisine was injected intraperitoneally into pilocarpine-induced epileptic rats for three weeks. Alpha-bungarotoxin (α-bgt), a specific α7nAChR antagonist, was used to evaluate the mechanism of action of cytisine. Rats were assayed for the occurrence of seizures and cognitive function by video surveillance and Morris water maze. Hippocampal injuries and synaptic structure were assessed by Nissl staining and Golgi staining. Furthermore, levels of glutamate, γ-aminobutyric acid (GABA), ACh, and α7nAChRs were measured. Results: Cytisine significantly reduced seizures and hippocampal damage while improving cognition and inhibiting synaptic remodeling in TLE rats. Additionally, cytisine decreased glutamate levels without altering GABA levels, and increased ACh levels and α7nAChR expression in the hippocampi of TLE rats. α-bgt antagonized the above-mentioned effects of cytisine treatment. Conclusion and Implications: Taken together, these findings indicate that cytisine exerted an anti-epileptic and neuroprotective effect in TLE rats via activation of α7nAChRs, which was associated with a decrease in glutamate levels, inhibition of synaptic remodeling, and improvement of cholinergic transmission in the hippocampus. Hence, our findings not only suggest that cytisine represents a promising anti-epileptic drug, but provides evidence of α7nAChRs as a novel therapeutic target for TLE.
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Mitogen-activated protein kinases (MPKs) play essential roles in guard cell signaling, but whether MPK cascades participate in guard cell ethylene signaling and interact with hydrogen peroxide (H2 O2 ), nitric oxide (NO), and ethylene-signaling components remain unclear. Here, we report that ethylene activated MPK3 and MPK6 in the leaves of wild-type Arabidopsis thaliana as well as ethylene insensitive2 (ein2), ein3, nitrate reductase1 (nia1), and nia2 mutants, but this effect was impaired in ethylene response1 (etr1), nicotinamide adenine dinucleotide phosphate oxidase AtrbohF, mpk kinase1 (mkk1), and mkk3 mutants. By contrast, the constitutive triple response1 (ctr1) mutant had constitutively active MPK3 and MPK6. Yeast two-hybrid, bimolecular fluorescence complementation, and pull-down assays indicated that MPK3 and MPK6 physically interacted with MKK1, MKK3, and the C-terminal region of EIN2 (EIN2 CEND). mkk1, mkk3, mpk3, and mpk6 mutants had typical levels of ethylene-induced H2 O2 generation but impaired ethylene-induced EIN2 CEND cleavage and nuclear translocation, EIN3 protein accumulation, NO production in guard cells, and stomatal closure. These results show that the MKK1/3-MPK3/6 cascade mediates ethylene-induced stomatal closure by functioning downstream of ETR1, CTR1, and H2 O2 to interact with EIN2, thereby promoting EIN3 accumulation and EIN3-dependent NO production in guard cells.
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Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Etilenos/farmacología , MAP Quinasa Quinasa 1/metabolismo , MAP Quinasa Quinasa 3/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Estomas de Plantas/efectos de los fármacos , Estomas de Plantas/metabolismo , Receptores de Superficie Celular/metabolismo , Factores de Transcripción/metabolismo , Arabidopsis/efectos de los fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Unión al ADN/genética , MAP Quinasa Quinasa 1/genética , MAP Quinasa Quinasa 3/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Receptores de Superficie Celular/genética , Factores de Transcripción/genéticaRESUMEN
Temporal lobe epilepsy (TLE) is a chronic neurological disorder that is a refractory disease. Baicalein possesses various pharmacological activities, including neuroprotection in neurodegenerative disease. However, whether baicalein is protective in the treatment of TLE is not determined. Therefore, the present study investigated the role of baicalein in the treatment of TLE. Baicalein was injected intraperitoneally to TLE rats for two weeks after the onset of spontaneous recurrent seizures (SRS). Rats were observed for the occurrence of SRS, and cognitive and hippocampus injuries were evaluated. Oxidative stress and inflammatory cytokines were measured. Corticosterone and its receptor, actin-associated protein F-actin and cofilin-1 were investigated in the brains of epileptic rats. Baicalein significantly improved cognition and reduced hippocampus damage and mossy fibre sprouting in TLE rats without obvious SRS suppression. Baicalein produced excellent anti-oxidative and anti-inflammatory effects in TLE rats. Baicalein restored the disruption of the glucocorticoid signal pathway and actin-associated protein in TLE rats. These results suggest that the neuroprotective effects of baicalein on cognition and the hippocampus are associated with the suppression of oxidative stress and inflammation and the regulation of the glucocorticoid pathway and actin-associated protein in TLE rats. This evidence supports the use of baicalein as an adjuvant agent for epilepsy treatment.
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Epilepsia del Lóbulo Temporal/tratamiento farmacológico , Flavanonas/farmacología , Animales , Encéfalo/metabolismo , Cofilina 1 , Cognición/efectos de los fármacos , Trastornos del Conocimiento/tratamiento farmacológico , Disfunción Cognitiva/metabolismo , Corticosterona , Modelos Animales de Enfermedad , Electroencefalografía , Epilepsia/tratamiento farmacológico , Epilepsia/metabolismo , Epilepsia del Lóbulo Temporal/metabolismo , Flavanonas/metabolismo , Hipocampo/metabolismo , Masculino , Enfermedades Neurodegenerativas/metabolismo , Neuronas/metabolismo , Fármacos Neuroprotectores/farmacología , Ratas , Ratas Sprague-Dawley , Convulsiones/metabolismo , Estado Epiléptico/metabolismo , Lóbulo Temporal/metabolismoRESUMEN
Pharmacological data have suggested the involvement of mitogen-activated protein kinase (MPK) cascades in dark-induced stomatal closure, but which specific MPK cascade participates in the darkness guard cell signaling and its relationship with hydrogen peroxide (H2O2) and nitric oxide (NO) remain unclear. In this paper, we observed that darkness induced activation of MPK6 in leaves of wild-type Arabidopsis (Arabidopsis thaliana) and mutants for nitrate reductase 1 (NIA1), but this effect was inhibited in mutants for MPK Kinase 1 (MEK1) and ATRBOHD/F. Mutants for MEK1, MPK6 and NIA1 showed defect of dark-induced NO production in guard cells and stomatal closure, but were normal in the dark-induced H2O2 generation, while stomata of mutant AtrbohD/F showed defect of dark-induced H2O2 and NO production and subsequent closure. Moreover, exogenous NO rescued the defect of dark-induced stomatal closure in mutants of AtrbohD/F, mek1 and mpk6, while exogenous H2O2 could not rescue the defect of dark-induced stomatal closure in mutants of mek1, mpk6 and nia1. These genetic and biochemical evidences not only show that MEK1-MPK6 cascade, AtRBOHD/F-dependent H2O2 and NIA1-dependent NO are all involved in dark-induced stomatal closure in Arabidopsis, also indicate that MEK1-MPK6 cascade functions via working downstream of H2O2 and upstream of NO.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/fisiología , Oscuridad , Peróxido de Hidrógeno/metabolismo , MAP Quinasa Quinasa 1/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Óxido Nítrico/metabolismo , Estomas de Plantas/metabolismo , Estomas de Plantas/fisiología , Proteínas de Arabidopsis/genética , MAP Quinasa Quinasa 1/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Nitrato-Reductasa/genética , Nitrato-Reductasa/metabolismoRESUMEN
OBJECTIVE: Acid-sensing ion channels (ASICs) are members of the degenerin/epithelial sodium channel (DEG/ENaC) protein superfamily and play a critical role in acid-induced cell injury. In this study, we examined whether drugs such as amiloride that block ASICs could attenuate acid-induced apoptotic injury to articular chondrocytes. METHODS: Articular chondrocytes were isolated from Sprague-Dawley rats, and their phenotype was determined by toluidine blue and immunocytochemical staining. Articular chondrocyte viability assay was performed with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). Apoptosis of chondrocytes was observed by the terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling method as well as propidium iodide labeling methods. Intracellular calcium ([Ca(2+)](i)) was analyzed by a Ca(2+)-imaging method. In addition, the expression levels of calpain and calcineurin in articular chondrocytes were examined by real-time PCR and immunocytochemical staining. The activity of caspase-3 was evaluated by spectrophotometric assays. RESULTS: Positive staining for glycosaminoglycan and collagen II was seen in articular chondrocytes. Blocking acid-sensing ion channels significantly decreased the cell death percentage and increased cell viability following acid exposure. After pretreated with amiloride, acid-induced [Ca(2+)](i) rises were reduced. Amiloride also inhibited calpain and calcineurin expression levels in acid-induced chondrocytes, and inhibited caspase-3 activity. CONCLUSION: The data presented in this study provided some experimental evidence that blocking ASICs could protect acid-induced apoptotic injury to chondrocytes.
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Condrocitos/metabolismo , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Canales Iónicos Sensibles al Ácido , Amilorida/farmacología , Animales , Apoptosis/efectos de los fármacos , Calcineurina/metabolismo , Calcio/metabolismo , Calpaína/metabolismo , Caspasa 3/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Condrocitos/efectos de los fármacos , Ácido Clorhídrico , Masculino , Ratas , Ratas Sprague-Dawley , Bloqueadores de los Canales de Sodio/farmacología , Canales de SodioRESUMEN
OBJECTIVE: The aim of this study was to examine whether drugs such as amiloride that block acid sensing ion channels (ASICs) could attenuate articular cartilage destruction in adjuvant-induced arthritis (AA). METHODS: Articular chondrocytes were isolated from the normal rats, and intracellular calcium ([Ca(2+)]i) was analyzed with laser scanning confocal microscopy. The cell injury was analyzed with lactate dehydrogenase release assay and electron microscopy. Amiloride or phosphate buffered saline was administered daily to AA rats for 1 week from the time of arthritis onset. Morphology of the articular cartilage was examined by hematoxylin and eosin staining, and Mankin score was calculated. The expression level of type II collagen (COII) and aggrecan mRNA and proteins in the articular cartilage was evaluated by real-time PCR and Western blotting, respectively. RESULTS: The rapid decrease in extracellular pH (6.0) induced a conspicuous increase in [Ca(2+)]i in the articular chondrocytes. Amiloride reduced this increase in [Ca(2+)]i, and inhibited acid-induced articular chondrocyte injury. Amiloride significantly decreased Mankin scores in the articular cartilage in AA rats. COII and aggrecan mRNA and protein expression in the articular cartilage was significantly increased by amiloride. CONCLUSION: These findings represent some experimental evidence of a potential role for ASICs in the pathogenesis of articular cartilage destruction in rheumatoid arthritis.
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Amilorida/farmacología , Artritis Experimental/patología , Cartílago Articular/citología , Condrocitos/efectos de los fármacos , Proteínas del Tejido Nervioso/metabolismo , Bloqueadores de los Canales de Sodio/farmacología , Canales de Sodio/metabolismo , Canales Iónicos Sensibles al Ácido , Agrecanos/metabolismo , Animales , Artritis Experimental/metabolismo , Células Cultivadas , Condrocitos/citología , Condrocitos/metabolismo , Colágeno Tipo II/metabolismo , Relación Dosis-Respuesta a Droga , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
Acid-sensing ion channels (ASICs) are cationic channels that are activated by extracellular acidification and implicated in pain perception, ischemic stroke, mechanosensation, learning, and memory. It has been shown that ASIC1a is an extracellular pH sensor in the central and peripheral nervous systems, but its physiological and pathological roles in non-neural cells are poorly understood. We demonstrated a novel physiological function of ASIC1a in rat articular chondrocytes. The expression of ASIC1a mRNA and protein in rat articular chondrocytes was evaluated by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting. The distribution of ASIC1a protein located in articular chondrocytes was determined by using immunofluorescence cell staining. The possible molecular mechanisms of articular chondrocytes pH sensing, as assessed by recording intracellular calcium ([Ca(2+)]i) in chondrocytes, were analyzed by using the laser scanning confocal microscopy technique. The cell injury following acid exposure was analyzed with lactate dehydrogenase release assay and electron microscopy. mRNA and protein expression showed that ASIC1a was expressed abundantly in these cells. In cultured chondrocytes, extracellular pH 6.0 increased intracellular calcium in the presence of extracellular Ca(2+). The ASIC1a-specific blocker PcTX venom significantly reduced this increase in [Ca(2+)]i, and inhibited acid-induced articular chondrocyte injury. However, the increase in [Ca(2+)]i and articular chondrocyte injury were not observed in the absence of extracellular Ca(2+). These findings show that increased [Ca(2+)]i, mediated via ASIC1a, might contribute to acidosis-induced articular chondrocyte injury.
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Calcio/metabolismo , Cartílago Articular/metabolismo , Condrocitos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Canales de Sodio/metabolismo , Canales Iónicos Sensibles al Ácido , Animales , Western Blotting , Cartílago Articular/efectos de los fármacos , Cartílago Articular/ultraestructura , Células Cultivadas , Condrocitos/efectos de los fármacos , Condrocitos/ultraestructura , Técnica del Anticuerpo Fluorescente , Concentración de Iones de Hidrógeno , L-Lactato Deshidrogenasa/metabolismo , Masculino , Microscopía Confocal , Microscopía Electrónica de Transmisión , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Proteínas del Tejido Nervioso/genética , Péptidos , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Bloqueadores de los Canales de Sodio/farmacología , Canales de Sodio/genética , Venenos de Araña/farmacología , Factores de TiempoRESUMEN
PURPOSE: To study the characters and etiology of oral ulcer and to propose the ways of prevention. METHODS: Summarize the 52 cases of oral ulcer in the earthquake area were summarized. RESULTS: The disease was related to the psychological tension, living regular and bad conditions. When the comprehensive therapies finished, the clinical curative rate was 82.7%(43/52), the efficacy was 15.4%(8/52), only one case was ineffective. CONCLUSIONS: Those patients who were diagnosed oral ulcer in the earthquake area need comprehensive therapies, including getting rid of the intensive emotion, improving the living conditions and paying attention to rest.