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1.
Medicine (Baltimore) ; 101(36): e30239, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36086787

RESUMEN

RATIONALE: Vulvar melanoma is a rare and aggressive tumor with a high risk of local recurrence and distant metastasis. The prognosis is poor with a 5-year overall survival rate of only 46.6%. Management of vulvar melanoma remains a clinical challenge. Recent evidences have shown that immune checkpoint inhibitors are effective in the treatment of vulvar melanoma. PATIENT CONCERNS AND DIAGNOSES: A 63-year-old woman with vulvar malignant melanoma suffered inguinal lymph node metastasis after vulvectomy and chemotherapy. She underwent inguinal lymph node dissection and inguinal radiotherapy. The tumor progressed again and she received immunotherapy. INTERVENTIONS: The tumor progressed again, and she was admitted to our hospital and received toripalimab combined with apatinib and abraxane. OUTCOMES: After 6 cycles of immunotherapy, the efficacy achieved partial remission. And with toripalimab as maintenance therapy, the patient achieved durable antitumor efficacy and good safety. LESSONS: In this rare case, the patient with metastatic vulvar malignant melanoma had durable antitumor efficacy and good safety when receiving toripalimab.


Asunto(s)
Melanoma , Neoplasias Primarias Secundarias , Neoplasias Cutáneas , Neoplasias de la Vulva , Anticuerpos Monoclonales Humanizados/uso terapéutico , Femenino , Humanos , Melanoma/patología , Persona de Mediana Edad , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias de la Vulva/patología
2.
Life (Basel) ; 12(7)2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35888046

RESUMEN

Complete ammonia oxidizers (comammox), which directly oxidize ammonia to nitrate, were recently identified and found to be ubiquitous in artificial systems. Research on the abundance and niche differentiation of comammox in the sludges of wastewater treatment plants (WWTPs) would be useful for improving the nitrogen removal efficiency of WWTPs. Here, we investigated the relative abundance and diversity of comammox in fifteen sludges of five WWTPs that use the anaerobic−anoxic−aerobic process in Jinan, China, via quantitative polymerase chain reaction and high-throughput sequencing of the 16S rRNA gene and ammonia monooxygenase gene. In the activated sludges in the WWTPs, comammox clade A.1 was widely distributed and mostly comprised Candidatus Nitrospira nitrosa-like comammox (>98% of all comammox). The proportion of this clade was negatively correlated (p < 0.01) with the dissolved oxygen (DO) level (1.7−8 mg/L), and slight pH changes (7.20−7.70) affected the structure of the comammox populations. Nitrospira lineage I frequently coexisted with Nitrosomonas, which generally had a significant positive correlation (p < 0.05) with the DO level. Our study provided an insight into the structure of comammox and other nitrifier populations in WWTPs that use the anaerobic−anoxic−aerobic process, broadening the knowledge about the effects of DO on comammox and other nitrifiers.

3.
Thorac Cancer ; 12(11): 1780-1783, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33949137

RESUMEN

Immune checkpoint inhibitors (ICIs) have achieved prominent efficacy in the treatment of numerous cancers, which is the most significant breakthrough in cancer therapy in recent years. However, ICIs are associated with a series of immune-related adverse events (irAEs). Pneumonitis is an uncommon but potentially fatal irAE. In the case reported here, a patient with advanced small cell lung cancer (SCLC) had rapid progression of disease following chemotherapy and received ICIs. The patient experienced severe immune-related hyperthermia followed by immune-related pneumonitis. Fortunately, a good clinical response was achieved after the patient received corticosteroids and tocilizumab.


Asunto(s)
Anticuerpos Monoclonales Humanizados/efectos adversos , Hipertermia/etiología , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Neoplasias Pulmonares/complicaciones , Neumonía/inducido químicamente , Carcinoma Pulmonar de Células Pequeñas/complicaciones , Adulto , Humanos , Hipertermia/patología , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico
4.
Appl Environ Microbiol ; 86(20)2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32826214

RESUMEN

Complete ammonia-oxidizing (comammox) bacteria play key roles in environmental nitrogen cycling and all belong to the genus Nitrospira, which was originally believed to include only strict nitrite-oxidizing bacteria (sNOB). Thus, differential estimation of sNOB abundance from that of comammox Nitrospira has become problematic, since both contain nitrite oxidoreductase genes that serve as common targets for sNOB detection. Herein, we developed novel comammox Nitrospira clade A- and B-specific primer sets targeting the α-subunit of the ammonia monooxygenase gene (amoA) and a sNOB-specific primer set targeting the cyanase gene (cynS) for quantitative PCR (qPCR). The high coverage and specificity of these primers were checked by use of metagenome and metatranscriptome data sets. Efficient and specific amplification with these primers was demonstrated using various environmental samples. Using the newly designed primers, we successfully estimated the abundances of comammox Nitrospira and sNOB in samples from two chloramination-treated drinking water systems and found that, in most samples, comammox Nitrospira clade A was the dominant type of Nitrospira and also served as the primary ammonia oxidizer. Compared with other ammonia oxidizers, comammox Nitrospira had a higher abundance in process water samples in these two drinking water systems. We also demonstrated that sNOB can be readily misrepresented by an earlier method, calculated by subtracting the comammox Nitrospira abundance from the total Nitrospira abundance, especially when the comammox Nitrospira proportion is relatively high. The new primer sets were successfully applied to comammox Nitrospira and sNOB quantification, which may prove useful in understanding the roles of Nitrospira in nitrification in various ecosystems.IMPORTANCENitrospira is a dominant nitrite-oxidizing bacterium in many artificial and natural environments. The discovery of complete ammonia oxidizers in the genus Nitrospira prevents the use of previously identified primers targeting the Nitrospira 16S rRNA gene or nitrite oxidoreductase (nxr) gene for differential determination of strict nitrite-oxidizing bacteria (sNOB) in the genus Nitrospira and among comammox bacteria in this genus. We designed three novel primer sets that enabled quantification of comammox Nitrospira clades A and B and sNOB with high coverage, specificity, and accuracy in various environments. With the designed primer sets, sNOB and comammox Nitrospira were differentially estimated in drinking water systems, and we found that comammox clade A predominated over sNOB and other ammonia oxidizers in process water samples. Accurate quantification of comammox Nitrospira and sNOB by use of the newly designed primers will provide essential information for evaluating the contribution of Nitrospira to nitrification in various ecosystems.


Asunto(s)
Amoníaco/metabolismo , Bacterias/clasificación , Cartilla de ADN/análisis , Nitritos/metabolismo , Bacterias/genética , Bacterias/metabolismo , Oxidación-Reducción
5.
Exp Neurol ; 327: 113249, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32070713

RESUMEN

Adult neurogenesis in hippocampus dentate gyrus (DG) is associated with the etiology on the early stage of Alzheimer's disease (AD). Factors that affect adult hippocampal neurogenesis have been shown to contribute to the neuropathology of AD. Adiponectin, a peptide hormone secreted by adipocytes, plays a critical role in insulin sensitizing, anti-inflammatory, and anti-diabetic effects in peripheral tissues. We previously showed that AdipoRon, as an agonist of adiponectin, promotes neurite outgrowth under ischemia. However, the role of AdipoRon on neural stem cells (NSCs) proliferation and cognitive dysfunction in the early stage of AD remains unknown. In this study, we investigated the role of AdipoRon on cognitive dysfunction and deficits of NSCs proliferation in AD. The in vivo study showed that AdipoRon improved either cognitive dysfunction or impaired NSCs proliferation in hippocampus DG region in APP/PS1 transgenic (Tg) mice. In addition, AdipoRon treatment also suppressed the ß-amyloid (Aß) deposition and inhibited ß-secretase 1(BACE1) expression in both cortex and hippocampus of APP/PS1 Tg mice. The in vitro study further suggested that AdipoRon significantly alleviated Aß-induced cell viability and neuronal morphology in primary neurons. Both AdipoR1 silencing and compound C, inhibitor of AMPK, completely abolished the effect of AdipoRon. Interestingly, AdipoRon also protected the dissipation of the ΔΨm caused by Aß toxicity in primary neurons, which was reversed by compound C. In NE-4C NSCs, AdipoRon significantly promoted the Aß-induced impaired cell proliferation through AdipoR1/AMPK/CREB pathway. Furthermore, inhibition of AMPK by compound C also reversed the promotive effects of AdipoRon on cognition and proliferation of NSCs of APP/PS1 Tg mice, suggesting a AMPK-dependent mechanism by AdipoRon in AD in vivo. Taken together, these results suggested that AdipoRon alleviated the cognitive dysfunction of AD mice, inhibited the Aß deposition by inhibiting BACE1 expression and promoted the impaired hippocampal NSCs proliferation on the early stage in vivo. The mechanisms involved activation of AdipoR1/AMPK pathway. Therefore, AdipoRon might be a potential candidate for the treatment of AD on the early stage.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Cognición/efectos de los fármacos , Disfunción Cognitiva/tratamiento farmacológico , Células-Madre Neurales/efectos de los fármacos , Piperidinas/farmacología , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Enfermedad de Alzheimer/metabolismo , Animales , Disfunción Cognitiva/metabolismo , Modelos Animales de Enfermedad , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Ratones , Ratones Transgénicos , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Piperidinas/uso terapéutico , Receptores de Adiponectina/metabolismo
6.
Appl Environ Microbiol ; 84(24)2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-30315079

RESUMEN

The discovery of complete ammonia oxidizers (comammox) refutes the century-old paradigm that nitrification requires the activity of two types of microbes. Determining the distribution and abundance of comammox in various environments is important for revealing the ecology of microbial nitrification within the global nitrogen cycle. In this study, the ubiquity and diversity of comammox were analyzed for samples from different types of environments, including soil, sediment, sludge, and water. The results of a two-step PCR using highly degenerate primers (THDP-PCR) and quantitative real-time PCR (qPCR) supported the relatively high abundance of comammox in nearly half of all samples tested, sometimes even outnumbering canonical ammonia-oxidizing bacteria (AOB). In addition, a relatively high proportion of comammox in tap and coastal water samples was confirmed via analysis of metagenomic data sets in public databases. The diversity of comammox was estimated by comammox-specific partial nested PCR amplification of the ammonia monooxygenase subunit A (amoA) gene, and phylogenetic analysis of comammox AmoA clearly showed a split of clade A into clades A.1 and A.2, with the proportions of clades A.1, A.2, and B differing among the various environmental samples. Moreover, compared to the amoA genes of AOB and ammonia-oxidizing archaea (AOA), the comammox amoA gene exhibited higher diversity indices. The ubiquitous distribution and high diversity of comammox indicate that they are likely overlooked contributors to nitrification in various ecosystems.IMPORTANCE The discovery of complete ammonia oxidizers (comammox), which oxidize ammonia to nitrate via nitrite, refutes the century-old paradigm that nitrification requires the activity of two types of microbes and redefines a key process in the biogeochemical nitrogen cycle. Understanding the functional relationships between comammox and other nitrifiers is important for ecological studies on the nitrogen cycle. Therefore, the diversity and contribution of comammox should be considered during ecological analyses of nitrifying microorganisms. In this study, a ubiquitous and highly diverse distribution of comammox was observed in various environmental samples, similar to the distribution of canonical ammonia-oxidizing bacteria. The proportion of comammox was relatively high in coastal water and sediment samples, whereas it was nearly undetectable in open-ocean samples. The ubiquitous distribution and high diversity of comammox indicate that these microorganisms might be important contributors to nitrification.


Asunto(s)
Amoníaco/metabolismo , Archaea/metabolismo , Bacterias/metabolismo , Archaea/genética , Bacterias/genética , Sedimentos Geológicos/química , Metagenómica , Nitratos/metabolismo , Nitrificación , Nitritos/metabolismo , Ciclo del Nitrógeno , Oxidación-Reducción , Oxidorreductasas/genética , Filogenia , Aguas del Alcantarillado/química , Suelo/química , Microbiología del Suelo , Agua/química
7.
Medicine (Baltimore) ; 97(36): e12222, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30200142

RESUMEN

The treatment of advanced triple-negative breast cancer, which failed in first-line or second-line therapy, is a significant challenge. We conducted this retrospective study to explore the efficacy and safety of apatinib and capecitabine as the third-line treatment for advanced triple-negative breast cancer.This retrospective study involved 44 advanced triple-negative breast cancer patients who failed in first-line or second-line therapy in Tangshan People's Hospital from January 2016 to February 2017. Twenty-two patients received apatinib and capecitabine, while 22 patients were treated with capecitabine monotherapy as third-line therapy. The progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and adverse events were compared between 2 groups.The apatinib and capecitabine group exhibited a higher PFS than capecitabine group (P = .001). Meanwhile, ORR and DCR in apatinib and capecitabine group were better than in capecitabine group (P = .042; .016). The 2 groups showed no significant difference in adverse events except degree I-II bleeding (P = .021). Both the apatinib and capecitabine and the capecitabine regimens revealed good tolerability.The apatinib and capecitabine regimen can achieve a better efficacy and similar serious adverse events compared with capecitabine regimen as the third-line treatment for advanced triple-negative breast cancer.


Asunto(s)
Antineoplásicos/administración & dosificación , Capecitabina/administración & dosificación , Piridinas/administración & dosificación , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Antineoplásicos/efectos adversos , Capecitabina/efectos adversos , Supervivencia sin Enfermedad , Resistencia a Antineoplásicos , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Hemorragia/inducido químicamente , Humanos , Persona de Mediana Edad , Piridinas/efectos adversos , Retratamiento , Estudios Retrospectivos , Resultado del Tratamiento
8.
Front Microbiol ; 9: 93, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29445367

RESUMEN

Intertidal mudflats are land-sea interaction areas and play important roles in global nutrient cycles. However, a comprehensive understanding of microbial communities in these mudflats remains elusive. In this study, mudflat sediment samples from the Dongtan wetland of Chongming Island, the largest alluvial island in the world, were collected. Using a modified metatranscriptomic method, the depth-wise distributions of potentially active microbial communities were investigated based on small subunit ribosomal RNA (SSU rRNA) sequences. Multiple environmental factors were also measured and analyzed in conjunction with the prokaryotic composition profiles. A prokaryotic diversity analysis based on the metatranscriptome datasets revealed two or threefold higher diversity indices (associated with potentially active microbes participating in biogeochemical processes in Dongtan) compared with the diversity indices based on 16S rRNA gene amplicons. Bacteria were numerically dominant relative to archaea, and the potentially active prokaryotic taxa were mostly assigned to the bacterial phyla Chloroflexi, Acidobacteria, and Bacteroidetes and the classes Delta- and Gamma-proteobacteria, along with the archaeal lineages phylum Bathyarchaeota and the order Thermoplasmatales. The total nitrogen and carbon content of the sediment samples were environmental factors that significantly affected the depth-wise distributions of both bacterial and archaeal communities. Furthermore, the activity of potentially active taxa (including the prevalent order Desulfobacterales and family Anaerolineaceae) appeared to be significantly underestimated by PCR-based methods, notably at the DNA level, and indicates that using normal PCR amplification of DNA limits the study of potential microbial activity. This is the first study of potentially active microbial communities in depth-wise sediments from Dongtan. The improved knowledge of microbial communities in Dongtan provides a foundation for exploring biogeochemical cycling and microbial functions.

9.
Bio Protoc ; 7(12): e2354, 2017 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-34541101

RESUMEN

We describe a two-step PCR strategy using tagged highly degenerate primer (THDP-PCR) targeting copper-containing membrane-bound monooxygenases (CuMMO) genes for community analysis of methane- or ammonia-oxidizing bacteria. This strategy consists of a primary CuMMO gene-specific PCR followed by a secondary PCR with a tag as a single primer. This strategy remarkably increases the divergence of CuMMO gene amplicons while maintaining PCR efficiency without obvious amplification bias. This THDP-PCR strategy can be extended to other functional gene-based community analysis with design of new highly degenerate primer covering target functional gene sequences.

10.
FEMS Microbiol Ecol ; 93(3)2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27940646

RESUMEN

The copper-containing membrane-bound monooxygenase (CuMMO) family comprises key enzymes for methane or ammonia oxidation: particulate methane monooxygenase (PMMO) and ammonia monooxygenase (AMO). To comprehensively amplify CuMMO genes, a two-step PCR strategy was developed using a newly designed tagged highly degenerate primer (THDP; degeneracy = 4608). Designated THDP-PCR, the technique consists of primary CuMMO gene-specific PCR followed by secondary PCR with a tag as a single primer. No significant bias in THDP-PCR amplification was found using various combinations of template mixtures of pmoA and amoA genes, which encode key subunits of the pMMO and AMO enzymes, respectively, from different microbes. THDP-PCR was successfully applied to nine different environmental samples and revealed relatively high contents of complete ammonia oxidation (Comammox)-related bacteria and a novel group of the CuMMO family. The levels of freshwater cluster methanotrophs obtained by THDP-PCR were much higher than those obtained by conventional methanotroph-specific PCR. The THDP-PCR strategy developed in this study can be extended to other functional gene-based community analyses, particularly when the target gene sequences lack regions of high consensus for primer design.


Asunto(s)
Amoníaco/metabolismo , Bacterias/genética , Metano/metabolismo , Oxigenasas de Función Mixta/genética , Bacterias/metabolismo , Betaproteobacteria/genética , Cobre , Cartilla de ADN/genética , Oxidación-Reducción , Oxidorreductasas , Oxigenasas , Reacción en Cadena de la Polimerasa/métodos
11.
Carbohydr Polym ; 152: 575-582, 2016 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-27516306

RESUMEN

A delignification method was employed to extract the polysaccharide from the fruiting body of Phellinus baumii. The three parameters, processing temperature, ratio of water to raw material and amount of acetic acid every time were optimized using the Box-Behnken design. As a result, the optimal extraction conditions were: processing temperature 70.3°C, ratio of water to raw material of 34.7mL/g and amount of acetic acid of 0.32mL every time. Under these conditions, the highest yield of polysaccharide (10.28%) was obtained. The main fraction (PPB-2) purified from PPB was composed of fucose, arabinose, galactose, glucose, xylose and mannose, while glucose was the predominant monosaccharide. PPB-2 exhibited noticeable antioxidant activity and strong protection against oxidative DNA damage. These findings implied that acid-chlorite delignification was a superior method to extract the polysaccharide from P. baumii and PPB-2 may be useful for cancer chemoprevention.


Asunto(s)
Antioxidantes , Basidiomycota/química , Daño del ADN , Polisacáridos Fúngicos , Plásmidos/química , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Polisacáridos Fúngicos/química , Polisacáridos Fúngicos/aislamiento & purificación
12.
Oncol Lett ; 9(2): 994-998, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25624919

RESUMEN

Accumulating evidence indicates that polymorphisms in the CRP gene are important in the development of cancer. The current meta-analysis was performed to investigate the association between CRP polymorphisms 3407 A>G (rs2808630) and 29 A>T (rs1417938), and the risk of developing cancer. A search of the relevant literature was conducted using the PubMed database to identify eligible studies published up until March 25, 2014. Five case-control studies involving 888 cases and 3,167 controls for the 3407 A>G polymorphism, and six case-control studies involving 3,110 cases and 5,951 controls for the 29 A>T polymorphism were included in the current meta-analysis. The pooled odds ratios with 95% confidence intervals were calculated using the fixed- or random-effects model. Meta-analysis identified no association between the CRP 3407 A>G and 29 A>T polymorphisms, and overall cancer risk. Additional stratified analysis by cancer type did not reveal any significant associations in the genetic models investigated. The findings of the present study indicated that CRP 3407 A>G and 29 A>T polymorphisms are not associated with cancer risk.

13.
Front Microbiol ; 4: 243, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23986751

RESUMEN

The effect of plant invasion on the microorganisms of soil sediments is very important for estuary ecology. The community structures of methanogens and sulfate-reducing bacteria (SRB) as a function of Spartina alterniflora invasion in Phragmites australis-vegetated sediments of the Dongtan wetland in the Yangtze River estuary, China, were investigated using 454 pyrosequencing and quantitative real-time PCR (qPCR) of the methyl coenzyme M reductase A (mcrA) and dissimilatory sulfite-reductase (dsrB) genes. Sediment samples were collected from two replicate locations, and each location included three sampling stands each covered by monocultures of P. australis, S. alterniflora and both plants (transition stands), respectively. qPCR analysis revealed higher copy numbers of mcrA genes in sediments from S. alterniflora stands than P. australis stands (5- and 7.5-fold more in the spring and summer, respectively), which is consistent with the higher methane flux rates measured in the S. alterniflora stands (up to 8.01 ± 5.61 mg m(-2) h(-1)). Similar trends were observed for SRB, and they were up to two orders of magnitude higher than the methanogens. Diversity indices indicated a lower diversity of methanogens in the S. alterniflora stands than the P. australis stands. In contrast, insignificant variations were observed in the diversity of SRB with the invasion. Although Methanomicrobiales and Methanococcales, the hydrogenotrophic methanogens, dominated in the salt marsh, Methanomicrobiales displayed a slight increase with the invasion and growth of S. alterniflora, whereas the later responded differently. Methanosarcina, the metabolically diverse methanogens, did not vary with the invasion of, but Methanosaeta, the exclusive acetate utilizers, appeared to increase with S. alterniflora invasion. In SRB, sequences closely related to the families Desulfobacteraceae and Desulfobulbaceae dominated in the salt marsh, although they displayed minimal changes with the S. alterniflora invasion. Approximately 11.3 ± 5.1% of the dsrB gene sequences formed a novel cluster that was reduced upon the invasion. The results showed that in the sediments of tidal salt marsh where S. alterniflora displaced P. australis, the abundances of methanogens and SRB increased, but the community composition of methanogens appeared to be influenced more than did the SRB.

14.
Biochem Pharmacol ; 85(9): 1352-62, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23435353

RESUMEN

A-type K(+) channels are crucial in controlling neuronal excitability, and their regulation in sensory neurons may alter pain sensation. In this study, we identified the functional role of cobrotoxin, the short-chain α-neurotoxin isolated from Naja atra venom, which acts in the regulation of the transient A-type K(+) currents (IA) and membrane excitability in dorsal root ganglion (DRG) neurons via the activation of the muscarinic M3 receptor (M3R). Our results showed that cobrotoxin increased IA in a concentration-dependent manner, whereas the sustained delayed rectifier K(+) currents (IDR) were not affected. Cobrotoxin did not affect the activation of IA markedly, however, it shifted the inactivation curve significantly in the depolarizing direction. The cobrotoxin-induced IA response was blocked by the M3R-selective antagonists DAU-5884 and 4-DAMP. An siRNA targeting the M3R in small DRG neurons abolished the cobrotoxin-induced IA increase. In addition, dialysis of the cells with the novel protein kinase C-delta isoform (PKC-δ) inhibitor δv1-1 or an siRNA targeting PKC-δ abolished the cobrotoxin-induced IA response, whereas inhibition of PKA or classic PKC activity elicited no such effects. Moreover, we observed a significant decrease in the firing rate of the neuronal action potential induced by M3R activation. Pretreatment of the cells with 4-aminopyridine, a selective blocker of IA, abolished this effect. Taken together, these results suggest that the short-chain cobrotoxin selectively enhances IA via a novel PKC-δ-dependent pathway. This effect occurred via the activation of M3R and might contribute to its neuronal hypoexcitability in small DRG neurons.


Asunto(s)
Membrana Celular/fisiología , Proteínas Neurotóxicas de Elápidos/farmacología , Ganglios Espinales/fisiología , Proteínas de Interacción con los Canales Kv/fisiología , Neuronas/fisiología , Proteína Quinasa C-delta/fisiología , Animales , Membrana Celular/efectos de los fármacos , Ganglios Espinales/citología , Técnicas de Silenciamiento del Gen , Técnicas In Vitro , Ratones , Neuronas/efectos de los fármacos , Técnicas de Placa-Clamp , Proteína Quinasa C-delta/genética , Receptor Muscarínico M3/fisiología
15.
Microb Ecol ; 66(2): 257-67, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23306392

RESUMEN

Methanogen populations of an intertidal mudflat in the Yangtze River estuary of China were investigated based on the methyl coenzyme M reductase A (mcrA) gene using 454-pyrosequencing and quantitative real-time polymerase chain reaction (qPCR). Samples were collected at six depths from three locations. In the qPCR analyses, a mean depth-wise change of mcrA gene abundance was observed from (1.23 ± 0.13) × 10(7) to (1.16 ± 0.29) × 10(8) per g dried soil, which was inversely correlated with the depletion of sulfate (R(2) = 0.74; α = 0.05) and salinity (R (2) = 0.66; α = 0.05). The copy numbers of mcrA was at least 1 order of magnitude higher than dissimilatory sulfate reductase B (dsrB) genes, likely indicating the importance of methanogenesis at the mudflat. Sequences related to the orders Methanomicrobiales, Methanosarcinales, Methanobacteriales, Methanococcales and the uncultured methanogens; Rice Cluster I (RC-I), Zoige cluster I (ZC-I) and anaerobic methane oxidizing archaeal lineage-1 (ANME-1) were detected. Methanomicrobiales and Methanosarcinales dominated the entire sediment layers, but detectable changes of proportions were observed with depth. The hydrogenotrophic methanogens Methanomicrobiales slightly increased with depth while Methanosarcinales showed the reverse. Chao1 and ACE richness estimators revealed higher diversity of methanogens near the surface (0-10 cm) when compared with the bottom sediments. The near-surface sediments were mainly dominated by the family Methanosarcinaceae (45 %), which has members that can utilize substrates that cannot be used by sulfate-reducing bacteria. Overall, current data indicate that Methanosarcinales and Methanomicrobiales are the most dominant methanogens within the entire depth profile down to 100 cm, with higher abundance and diversity of methanogens in the deeper and upper sediment layers, respectively.


Asunto(s)
Bacterias/enzimología , Bacterias/aislamiento & purificación , Proteínas Bacterianas/genética , Sedimentos Geológicos/microbiología , Metano/metabolismo , Oxidorreductasas/genética , Ríos/microbiología , Bacterias/clasificación , Bacterias/genética , Proteínas Bacterianas/metabolismo , China , Ecosistema , Oxidorreductasas/metabolismo , Filogenia
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