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1.
Stroke ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38881452

RESUMEN

BACKGROUND: Surgical risk assessment is intriguing for clinical decision-making of brainstem cavernous malformation (BSCM) treatment. While the BSCM grading scale, encompassing size, developmental venous anomaly, crossing axial midpoint, age, and timing of intervention, is increasingly utilized, the clinical relevance of neurological fluctuation and recurrent hemorrhage has not been incorporated. This study aimed to propose a supplementary grading scale with enhanced predictive efficacy. METHODS: Using a retrospective nationwide registry of consecutive patients with BSCMs undergoing surgery in China from March 2011 to May 2023, a new supplementary BSCM grading scale was developed from a derivative cohort of 260 patients and validated in an independent concurrent cohort of 67 patients. The primary outcome was unfavorable neurological function (modified Rankin Scale score >2) at the latest follow-up. The performance of the supplementary grading system was evaluated for discrimination, calibration, and clinical utility and further compared with its original counterpart. RESULTS: Over a follow-up of at least 6 months after surgery, the unfavorable outcomes were 31% in the overall cohort (101/327 patients). A preoperative motor deficit (odds ratio, 3.13; P=0.001), recurrent hemorrhage (odds ratio, 3.05; P<0.001), timing of intervention (odds ratio, 7.08; P<0.001), and crossing the axial midpoint (odds ratio, 2.57; P=0.006) were associated with the unfavorable outcomes and composed the initial Huashan grading variables. A supplementary BSCM grading system was subsequently developed by incorporating the Huashan grading variables into the original BSCM grading scale. The predictive capability of the supplementary scale was consistently superior to the original counterpart in either the derivative cohort (area under the receiver operating characteristic curve, 0.74 [95% CI, 0.68-0.80] for the supplementary versus 0.68 [95% CI, 0.61-0.74] for the original) or the validation cohort (0.75 [95% CI, 0.62-0.87] versus 0.64 [95% CI, 0.48-0.81]). CONCLUSIONS: This study highlights the neurological relevance of BSCM hemorrhage in surgical risk assessment. Via compositing preoperative motor function and recurrent hemorrhages, a supplementary grading scale may improve a dynamic risk assessment for clinical decisions in the management of BSCMs.

2.
Environ Res ; 256: 119207, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38782345

RESUMEN

The Laptev Sea is a major Marginal Sea in the Western Arctic Ocean. The Arctic amplification brought by global warming influences the hydrological properties of rivers passing through the permafrost zone, which would alter the biological community structure at continental margin. In this study, the structure, assembly, and gene expression of planktonic microbial communities in two estuaries (Protoka Ularovskaya River Estuary, PURE; Lena River Estuary, LRE) of Laptev Sea were examined to investigate the environmental effects of polar rivers. PURE and LRE exhibited distinct environmental characteristics: low temperature and high salinity for PURE, and high temperature and low salinity for LRE, influenced by runoff size. Salinity more closely influenced microbial communities in LRE, with freshwater species playing a significant role in community composition. The findings revealed differences between two estuaries in community composition and diversity. Prokaryotes and microeukaryotes had shown different assembly patterns in response to habitat changes caused by terrestrial freshwater input. Furthermore, compared with the PURE, the co-occurrence and inter-domain network of the LRE, which was more affected by terrestrial input, was more complex and stable. Functional gene prediction revealed a higher gene expression of methane metabolism in LRE than in PURE, particularly those related to methane oxidation, and this conclusion could help better explore the impact of global warming on the methane cycle in the Arctic Marginal Seas. This study explored the increased freshwater runoffs under the background of global warming dramatically affect Arctic microplankton communities from community structure, assembly and gene expression aspects.


Asunto(s)
Estuarios , Regiones Árticas , Plancton/genética , Expresión Génica , Salinidad
3.
Int J Mol Sci ; 25(4)2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38396857

RESUMEN

The differentiation and developmental trajectory of fish gonads, significantly important for fish breeding, culture, and production, has long been a focal point in the fields of fish genetics and developmental biology. However, the mechanism of gonadal differentiation in leopard coral grouper (Plectropomus leopardus) remains unclear. This study investigates the 17ß-Hydroxysteroid Dehydrogenase (Hsd17b) gene family in P. leopardus, with a focus on gene characterization, expression profiling, and functional analysis. The results reveal that the P. leopardus's Hsd17b gene family comprises 11 members, all belonging to the SDR superfamily. The amino acid similarity is only 12.96%, but conserved motifs, such as TGxxxGxG and S-Y-K, are present in these genes. Hsd17b12a and Hsd17b12b are unique homologs in fish, and chromosomal localization has confirmed that they are not derived from different transcripts of the same gene, but rather are two independent genes. The Hsd17b family genes, predominantly expressed in the liver, heart, gills, kidneys, and gonads, are involved in synthesizing or metabolizing sex steroid hormones and neurotransmitters, with their expression patterns during gonadal development categorized into three distinct categories. Notably, Hsd17b4 and Hsd17b12a were highly expressed in the testis and ovary, respectively, suggesting their involvement in the development of reproductive cells in these organs. Fluorescence in situ hybridization (FISH) further indicated specific expression sites for these genes, with Hsd17b4 primarily expressed in germ stem cells and Hsd17b12a in oocytes. This comprehensive study provides foundational insights into the role of the Hsd17b gene family in gonadal development and steroidogenesis in P. leopardus, contributing to the broader understanding of fish reproductive biology and aquaculture breeding.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas , Lubina , Animales , Masculino , Femenino , Hibridación Fluorescente in Situ , Gónadas/metabolismo , Testículo/metabolismo
4.
Bioorg Chem ; 131: 106316, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36508939

RESUMEN

The recent global Omicron epidemics underscore the great need for the development of small molecule therapeutics with appropriate mechanisms. The trimeric spike protein (S) of SARS-CoV-2 plays a pivotal role in mediating viral entry into host cells. We continued our efforts to develop small-molecule SARS-CoV-2 entry inhibitors. In this work, two sets of BA derivatives were designed and synthesized based on the hit BA-1 that was identified as a novel SARS-CoV-2 entry inhibitor. Compound BA-4, the most potent one, showed broad inhibitory activities against pOmicron and other pseudotyped variants with EC50 values ranging 2.73 to 5.19 µM. Moreover, pSARS-CoV-2 assay, SPR analysis, Co-IP assay and the cell-cell fusion assay coupled with docking and mutagenesis studies revealed that BA-4 could stabilize S in the pre-fusion step to interfere with the membrane fusion, thereby displaying promising inhibition against Omicron entry.


Asunto(s)
COVID-19 , Inhibidores de Fusión de VIH , Ácido Oleanólico , Saponinas , Virosis , Humanos , SARS-CoV-2 , Ácido Oleanólico/farmacología
5.
Neurosurg Rev ; 46(1): 153, 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37365456

RESUMEN

Arteriovenous fistulas (AVFs) at the craniocervical junction (CCJ) are uncommon conditions with complex angioarchitecture. The objective of this study was to identify the angioarchitectural features of CCJ-AVF that were predictive of clinical presentation and neurological function. The study encompassed a total of 68 consecutive patients with CCJ-AVF at two neurosurgical centers between 2014 and 2022. Additionally, a systematic review was conducted, including 68 cases with detailed clinical data obtained via PubMed database spanning 1990 to 2022. Clinical and imaging data were collected and pooled together to analyze factors associated with subarachnoid hemorrhage (SAH), myelopathy, and modified Rankin scale (mRS) at presentation. The mean age of the patients was 54.5 ± 13.1 years, with 76.5% of them being male. The most common feeding arteries were V3-medial branches (33.1%), and drainage was frequently through the anterior or posterior spinal vein/perimedullary vein (72.8%). SAH was the most common presentation (49.3%), and an associated aneurysm was identified as a risk factor for SAH (adjusted OR, 7.44; 95%CI, 2.89-19.15). Anterior or posterior spinal vein/perimedullary vein (adjusted OR, 2.78; 95%CI, 1.00-7.72) and male gender (adjusted OR, 3.76; 95%CI, 1.23-11.53) were associated with higher risk for myelopathy. Myelopathy at presentation was an independent risk factor for unfavorable neurological status (adjusted OR per score, 4.73; 95%CI, 1.31-17.12) in untreated CCJ-AVF. The present study identifies risk factors associated with SAH, myelopathy, and unfavorable neurological status at presentation in patients with CCJ-AVF. These findings may help treatment decisions for these complex vascular malformations.


Asunto(s)
Fístula Arteriovenosa , Malformaciones Vasculares del Sistema Nervioso Central , Enfermedades de la Médula Espinal , Hemorragia Subaracnoidea , Humanos , Masculino , Adulto , Persona de Mediana Edad , Anciano , Femenino , Hemorragia Subaracnoidea/complicaciones , Fístula Arteriovenosa/complicaciones , Fístula Arteriovenosa/cirugía , Enfermedades de la Médula Espinal/cirugía , Malformaciones Vasculares del Sistema Nervioso Central/cirugía , Malformaciones Vasculares del Sistema Nervioso Central/complicaciones , Estudios Multicéntricos como Asunto
6.
Int J Syst Evol Microbiol ; 71(10)2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34694984

RESUMEN

The morphology and ciliature of a new freshwater ciliate, Frontonia apoacuminata sp. nov., isolated from an artificial pond in Qingdao, PR China, were investigated using live observation and silver staining methods. The main features separating F. apoacuminata sp. nov. from its congeners are as follows: a broad elliptical body that is slightly pointed at the posterior end, four ophryokineties, one or two spherical micronuclei of a 'compact' type, a dorsally positioned contractile vacuole, and peniculi 1-3 each with five kinetosome rows though the left-most two rows in peniculus 3 are extremely shortened (with only two or three kinetosomes each). Additionally, an improved diagnosis of F. acuminata is provided. Phylogenetic analyses based on the small subunit ribosomal RNA (SSU rRNA) gene show that F. apoacuminata sp. nov. clusters with F. atra, F. minuta, F. acuminata and F. terricola. These five species group with Disematostoma, Marituja and Stokesia rather than with other Frontonia species, causing polyphyly of the genus Frontonia.


Asunto(s)
Oligohimenóforos , Filogenia , Composición de Base , China , ADN Protozoario/genética , Agua Dulce/parasitología , Oligohimenóforos/clasificación , Oligohimenóforos/aislamiento & purificación , Análisis de Secuencia de ADN
7.
Ecotoxicol Environ Saf ; 222: 112504, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34265533

RESUMEN

This study aimed to investigate the intoxication mechanism of golden pompano (Trachinotus ovatus) exposed to high ammonia levels and the effects on the immune and antioxidant mechanisms of gills. Juvenile golden pompano was exposed to ammonia (total ammonia: 26.9 mg/L) to induce 96 h of ammonia stress, and a 96 h recovery experiment was performed after poisoning. Then, we evaluated hematological parameters, the histological structure and the expression of related genes. In this experiment, continuous exposure to high levels of ammonia led to a significant increase in plasma alkaline phosphatase (ALP), acid phosphatase (ACP) and lactate dehydrogenase (LDH) levels (P < 0.05), and the levels of triiodothyronine (T3) and tetraiodothyronine (T4) were significantly reduced (P < 0.05). Moreover, the expression of antioxidant genes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and inflammatory cytokines such as tumor necrosis factor α (TNF-α) and interleukin 1ß (IL-1ß) increased (P < 0.05). These results indicate that ammonia activates the active osmotic regulatory mechanism of fish gills and participates in defense and immune responses. However, with prolonged exposure to ammonia, the balance of the defense system is disrupted, leading to oxidative damage and inflammation of the gill tissue. This research not only helps elucidate the intoxication mechanism of golden pompano by ammonia at the molecular level but also provides a theoretical basis for further research on detoxification mechanisms.


Asunto(s)
Amoníaco , Branquias , Amoníaco/toxicidad , Alimentación Animal/análisis , Animales , Antioxidantes , Suplementos Dietéticos , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Branquias/metabolismo , Estrés Oxidativo , Transducción de Señal
8.
Int J Syst Evol Microbiol ; 70(4): 2405-2419, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32559827

RESUMEN

The morphology of two new scuticociliates, Uronema apomarinum sp. nov. and Homalogastra parasetosa sp. nov., isolated from a mangrove wetland in Shenzhen, PR China, was studied using live observation and the protargol impregnation method. Uronema apomarinum is characterized by a body size of about 20-35×10-15 µm in vivo, a partly two-rowed membranelle 1, and 12 or 13 somatic kineties. Homalogastra parasetosa is distinguished by a membranelle 1 comprising two longitudinal rows of basal bodies. Three Homalogastra setosa populations are suggested as subjective synonyms of the new species. Improved diagnoses of the genus Homalogastra Kahl, 1926 and its type species Homalogastra setosa Kahl, 1926 are provided. Results of phylogenetic analyses based on 18S rRNA gene and ITS1-5.8S-ITS2 region sequences indicate that U. apomarinum is most closely related to U. marinum, while the closest relative of H. parasetosa is H. setosa.


Asunto(s)
Oligohimenóforos/clasificación , Filogenia , China , ADN Espaciador Ribosómico/genética , Oligohimenóforos/aislamiento & purificación , ARN Ribosómico 18S/genética , Análisis de Secuencia de ADN , Proteínas de Plata , Humedales
9.
J Eukaryot Microbiol ; 66(5): 836-848, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30927380

RESUMEN

Pseudocohnilembus persalinus is a free-living marine scuticociliate that, as a new model organism, has been used in a wide variety of studies. However, long-term laboratory maintenance for this species is mainly achieved by subculture that requires rigorous culture environments and, too often, cultures of the organism die out for a variety of reasons. Successful transport of viable cultures also poses problems for researchers. This study describes a simple and rapid protocol for long-term cryopreservation of P. persalinus. The effects of physiological states of individuals before freezing, the type and concentration of cryoprotectant, and optimal temperatures for freezing and thawing were assessed. A cryopreservation protocol, using a mixture of 30% glycerol and 70% concentrated P. persalinus cell culture, incorporating rate-controlled freezing at -80 °C before liquid nitrogen storage, maintained a high recovery efficiency after 8 wk of storage. These results suggest that broader application of this protocol to build a cryopreserved marine protozoa culture bank for biological studies may be possible.


Asunto(s)
Criopreservación/métodos , Oligohimenóforos/química , Criopreservación/instrumentación , Crioprotectores/análisis , Oligohimenóforos/crecimiento & desarrollo , Temperatura
10.
J Eukaryot Microbiol ; 63(6): 760-770, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27115713

RESUMEN

A cryptic species of the Tetrahymena pyriformis complex, Tetrahymena australis, has been known for a long time but never properly diagnosed based on taxonomic methods. The species name is thus invalid according to the International Code of Zoological Nomenclature. Recently, a population isolated from a freshwater lake in Wuhan, China was investigated using live observations, silver staining methods and gene sequence data. This organism can be separated from other described species of the T. pyriformis complex by its relatively small body size, the number of somatic kineties and differences in sequences of two genes, namely the small subunit ribosomal RNA (SSU rRNA) and the mitochondrial cytochrome c oxidase subunit I (cox1). We compared the SSU rRNA gene sequences of all available Tetrahymena species to reveal the nucleotide differences within this genus. The sequence of the Wuhan population is identical to two sequences of a previously isolated strain of T. australis (ATCC #30831). Phylogenetic analyses indicate that these three sequences (X56167, M98015, KT334373) cluster with Tetrahymena shanghaiensis (EF070256) in a polytomy. However, sequence divergence of the cox1 gene between the Wuhan population and another strain of T. australis (ATCC #30271) is 1.4%, suggesting that these may represent different subspecies.


Asunto(s)
Tetrahymena/clasificación , Tetrahymena/aislamiento & purificación , Secuencia de Bases , ADN Mitocondrial/genética , ADN Protozoario/genética , Agua Dulce/parasitología , Mitocondrias/genética , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN , Tetrahymena/genética
11.
Mar Life Sci Technol ; 6(2): 212-235, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38827127

RESUMEN

Species of the ciliate genera Myxophyllum and Conchophthirus are found as endocommensals of terrestrial and freshwater mollusks, respectively. So far, there have been few studies of these genera and morphological data for most members are often incomplete. In the present work, two new species, Myxophyllum weishanense sp. nov. and Conchophthirus paracurtus sp. nov., and a known species, Conchophthirus lamellidens, were isolated from hosts in Lake Weishan Wetland, China. Taxonomic studies indicate that M. weishanense sp. nov. can be recognized mainly by the combination of about 60 somatic kineties on both ventral and dorsal sides and the presence of caudal cilia. Conchophthirus paracurtus sp. nov. differs from congeners in its body shape and size, having a glabrous area on the posterior right side, and having fewer somatic kineties. In addition, differences in their ITS2 (Internally Transcribed Spacer 2) secondary structures support the discrimination of the two new species from their highly similar congeners. An improved diagnosis for the poorly known species, C. lamellidens is also provided. Phylogenetic analyses reveal that members of the genus Myxophyllum belong to a fully supported clade that is sister to a large, poorly supported clade consisting of Hemispeiridae, Ancistridae, and several lineages of the nonmonophyletic Cyclidiidae. The Myxophyllum clade also includes Protophyra ovicola JQ956552, a possible misidentification. Sequences of the two new Conchophthirus species cluster with other congeners in a fully supported clade that is unrelated to either the 'typical' thigmotrichs or to pleuronematids, thus conflicting with the traditional classification, and may represent an orphan scuticociliate lineage. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-024-00230-4.

12.
J Neurosurg ; : 1-11, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38820614

RESUMEN

OBJECTIVE: Craniocervical junction arteriovenous fistulas (CCJ-AVFs) are complex vascular shunts that present a challenge for treatment. The aim of this study was to compare the clinical outcomes of microsurgery and endovascular embolization for CCJ-AVFs and to determine whether the treatment approach affected the obliteration rate and neurological improvement. METHODS: The authors conducted a retrospective analysis of 64 patients who had undergone microsurgery or endovascular embolization for CCJ-AVF at one of two neurosurgical centers from January 2014 to February 2022. Additionally, a pooled analysis of 68 patients from 38 studies was performed. Baseline characteristics, angioarchitectural features, and clinical outcomes were compared between two treatment groups. A subgroup analysis of CCJ-AVFs with carotid artery (CA) feeders was also performed. RESULTS: In the multicenter cohort, the complete obliteration rate was 95.1% with microsurgery, 81.8% with embolization via the CA, and 50.0% with embolization via the vertebral artery (VA). After adjusting for baseline and confounding features, the occlusion rate was significantly lower in the VA embolization group (adjusted OR 41.06, 95% CI 2.37-711.9, p = 0.01). No new-onset infarctions occurred in the microsurgical group, whereas 1 patient each in the CA and VA embolization groups experienced posttreatment infarction. Microsurgery demonstrated a neurological improvement rate similar to that in the CA embolization group (65.9% vs 63.6%, respectively). In the subgroup analysis of CCJ-AVF with CA feeders in the multicenter cohort, the occlusion rate and neurological improvement in the CA embolization group were comparable to those in the microsurgery group. The subgroup analysis in the pooled analysis revealed complete obliteration rates of 100.0% in the microsurgical group, 88.9% in the CA embolization group, and 66.7% in the VA embolization group. CONCLUSIONS: This study supports microsurgery as the best treatment modality for CCJ-AVFs, exhibiting the highest rates of complete obliteration. Conversely, embolization via the VA can result in a lower occlusion rate and less neurological improvement. In CCJ-AVFs with CA feeders, embolization via the CA can be a safe and effective alternative to microsurgery.

13.
Int J Surg ; 110(4): 2217-2225, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38668661

RESUMEN

BACKGROUND: Brainstem cavernous malformations (BSCMs) often present with haemorrhage, but the optimal timing for microsurgical intervention remains unclear. This study aims to explore how intervention timing relates to neurological outcomes in haemorrhagic BSCM patients undergoing microsurgery, offering insights for clinical decisions. METHODS: A total of 293 consecutive patients diagnosed with BSCMs, who underwent microsurgery were identified between March 2011 and January 2023 at two comprehensive centres in China, with a postoperative follow-up duration exceeding 6 months. Utilizing logistic regression models with restricted cubic splines, distinct time groups were identified. Subsequently, matching weight analysis compared these groups in terms of outcomes, new haemorrhage rates, cranial nerve deficits, and perioperative complications. The primary outcome was an unfavourable outcome, which was defined as a mRS score greater than 2 at the latest follow-up. RESULTS: Among the 293 patients, 48.5% were female, median age was (39.9±14.3) years, and median haemorrhage-to-treatment time was 42 days. Patients were categorized into acute (≤21 days), subacute (22-42 days), and delay (>42 days) intervention groups. After matching, 186 patients were analyzed. Adjusted analysis showed lower unfavourable outcome rates for acute [adjusted odds ratio (OR), 0.73; 95% CI, 0.65-0.82; P<0.001] and subacute (adjusted OR, 0.83; 95% CI, 0.72-0.95; P=0.007) groups compared to the delay group. Subacute intervention led to fewer cranial nerve deficits (adjusted OR, 0.76; 95% CI, 0.66-0.88, P<0.001). New haemorrhage incidence didn't significantly differ among groups. CONCLUSIONS: For haemorrhagic BSCMs patients, delayed microsurgical intervention that exceeded 42 days after a prior haemorrhage were associated with an increased risk of unfavourable neurological outcomes.


Asunto(s)
Hemangioma Cavernoso del Sistema Nervioso Central , Microcirugia , Tiempo de Tratamiento , Humanos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Hemangioma Cavernoso del Sistema Nervioso Central/cirugía , Hemangioma Cavernoso del Sistema Nervioso Central/complicaciones , Tiempo de Tratamiento/estadística & datos numéricos , China/epidemiología , Estudios de Cohortes , Resultado del Tratamiento , Tronco Encefálico/cirugía , Estudios Retrospectivos
14.
Mar Pollut Bull ; 199: 115960, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38159383

RESUMEN

Prometryn has been extensively detected in marine environment because of its widespread usage in agriculture and aquaculture and has been concerns since its serious effects on aquatic organisms. However, its impact on the microbial community in the marine ecosystem including seawater and biofilm is still unclear. Therefore, a short-term indoor microcosm experiment of prometryn exposure was conducted. This study found that prometryn had a more significant impact on the structure and stability of the microbial community in seawater compared to microplastic biofilms. Additionally, we observed that the assembly of the microbial community in biofilms was more affected by stochastic processes than in seawater under the exposure of prometryn. Our study provided evidence for the increasing impact of the microbial communities under the stress of prometryn and microplastics.


Asunto(s)
Microbiota , Contaminantes Químicos del Agua , Microplásticos , Ecosistema , Plásticos , Prometrina , Agua de Mar/química , Biopelículas , Contaminantes Químicos del Agua/análisis
15.
Mar Pollut Bull ; 201: 116204, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38430678

RESUMEN

Protozoan ciliates represent a common biological contaminant during microalgae cultivation, which will lead to a decline in microalgae productivity. This study investigated the effectiveness of sodium dodecyl benzene sulfonate (SDBS) in controlling ciliate populations within microalgae cultures. SDBS concentrations of 160 mg/L and 100 mg/L were found to effectively manage the representative species of ciliates contamination by Euplotes vannus and Uronema marinum during the cultivation of Synechococcus and Chlorella, and the growth vitality of microalgae has been restored. Additionally, SDBS at these concentrations reduced oxidative stress resistance and induced membrane damage to remove biological pollutants by modulating enzyme activity, affecting lipid, energy, amino acid metabolism pathways, and processes such as translation and protein folding. This research provides insights into the mechanisms through which SDBS effectively combats protozoan ciliates during the microalgal cultivation. This contributes to reduce biological pollution, ensure the overall productivity and healthy and sustainable management of microalgae ecosystems.


Asunto(s)
Bencenosulfonatos , Chlorella , Cilióforos , Microalgas , Plaguicidas , Ecosistema , Biomasa
16.
Microorganisms ; 11(2)2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36838391

RESUMEN

The objective of this study was to evaluate the effects of Lactiplantibacillus plantarum or cellulase on the fermentation characteristics and bacterial community of mixed alfalfa (Medicago sativa L., AF) and Leymus chinensis (LC) silage. The harvested alfalfa and Leymus chinensis were cut into 1-2 cm lengths by a crop chopper and they were thoroughly mixed at a ratio of 3/2 (wet weight). The mixtures were treated with no addition (CON), Lactiplantibacillus plantarum (LP, 1 × 106 cfu/g fresh material), cellulase (CE, 7.5 × 102 U/kg fresh material) and their combination (LPCE). The forages were packed into triplicate vacuum-sealed, polyethylene bags per treatment and ensiled for 1, 3, 5, 7 and 30 d at room temperature (17-25 °C). Compared to the CON groups, all the additives increased the lactic acid content and decreased the pH and ammonia nitrogen content over the ensiling period. In comparison to the other groups, higher water-soluble carbohydrate contents were discovered in the CE-inoculated silages. Compared to the CON groups, the treatment with LPCE retained the crude protein content and reduced the acid detergent fiber content. The principal coordinate analysis based on the unweighted UniFrac distance showed that individuals in the AF, LC, CON and LPCE treatment could be significantly separated from each other. At the genus level, the bacterial community in the mixed silage involves a shift from Cyanobacteria_unclassified to Lactobacillus. Lactobacillus dominated in all the treatments until the end of the silage, but when added with Lactiplantibacillus plantarum, it was more effective in inhibiting undesirable microorganisms, such as Enterobacter, while reducing microbial diversity. By changing the bacterial community structure after applying Lactiplantibacillus plantarum and cellulase, the mixed silages quality could be further improved. During ensiling, the metabolism of the nucleotide and carbohydrate were enhanced whereas the metabolism of the amino acid, energy, cofactors and vitamins were hindered. In conclusion, the relative abundance of Lactobacillus in the mixed silage increased with the addition of Lactiplantibacillus plantarum and cellulase, which also improved the fermentation quality.

17.
Front Microbiol ; 14: 1197059, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37520349

RESUMEN

Objective: The objectives of this study were to evaluate the effects of different forage proportions in the fermented total mixed ration (FTMR) on growth performance, muscle fatty acid profile, and rumen microbiota of lambs. Methods: Thirty 6-month-old small tail Han sheep × Ujumqin lambs with initial body weight (BW) of 27.8 ± 0.90 kg were selected for the test and divided into two groups of 15 sheep in each treatment (three pens per treatment and five lambs per pen) according to the principle of homogeneity. Two isoenergetic and isonitrogenous diets were formulated according to the NRC. The diet treatments were designed as (1) OH treatment containing 25% alfalfa hay and 35% oat hay, and (2) AH treatment containing 35% alfalfa hay with 25% oat hay. The forage-to-concentrate ratio for both diets was 65: 35 (DM basis). Three replicates were randomly selected from each treatment to determine growth performance, fatty acid profile and rumen bacterial communities in lambs. Results: Results revealed no statistically significant (p > 0.05) differences in dry matter intake and average daily gain between the two diet groups. Cholesterol and intramuscular fat were significantly (p > 0.05) higher in the AH group, while no statistically significant difference (p > 0.05) was found in pH24 value. The muscle fatty acid compositions of lambs were obviously (p < 0.05) influenced by the diet treatments. Compared with the OH group, the C16:1, C17:0, and C20:3n6 contents were higher (p < 0.05) in the AH group, whereas the content of C18:1n9c, C20:1, C18:3n3, and C22:6n3 was obviously (p < 0.05) increased in the OH group. The monounsaturated fatty acid (MUFA) contents were significantly higher in the OH group, whereas no significant differences (p > 0.05) were detected in saturated fatty acid (SFA) and polyunsaturated fatty acid (PUFA) contents among the two diet treatments. Bacterial composition was generally separated into two clusters based on principal coordinate analysis, and the OH group had a higher Shannon index. The relative abundance at the genes level of the Rikenellaceae_RC9_gut_group was obviously (p < 0.05) increased in the AH group and the relative abundances of Prevotella_1, Fibrobacter, and Bacteroidales_UCG_001_unclassified were obviously (p < 0.05) enriched in the OH group. Integrated correlation analysis also underscored a possible link between the muscle fatty acid compositions and significantly altered rumen microbiota. Conclusion: Overall, oat-based roughage in FTMR could promote a beneficial lipid pattern in the Longissimus lumborum muscles of lambs. These findings provide a potential insight into diet effects on fatty acid profile and the rumen microbiome of lambs, which may help make decisions regarding feeding.

18.
J Hazard Mater ; 459: 132315, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37604038

RESUMEN

Nanoplastic is increasing in environments and can address toxic effects on various organisms. Particle size, concentration, and surface functionalization most influence nanoplastic toxicity. Besides, nanoplastic can adsorb other contaminants (e.g., antibiotics) to aggravate its adverse effects. The combined effects of nanoplastics and antibiotics on planktonic/benthic microbial communities, however, are still largely unknown. In this study, the combined effects of polystyrene nanoplastic and ofloxacin on the structure, assembly, and metabolic activities of marine microbial communities were investigated based on amplicon sequencing data. The results mainly demonstrate that: (1) nanoplastic and ofloxacin have greater impacts on prokaryotic communities than eukaryotic ones; (2) niche breadths of planktonic prokaryotes and benthic eukaryotes were shrank with both high nanoplastic and ofloxacin concentrations; (3) increased ofloxacin mainly reduces nodes/edges of co-occurrence networks, while nanoplastic centralizes network modularity; (4) increased nanoplastic under high ofloxacin concentration induces more differential prokaryotic pathways in planktonic communities, while benthic communities are less influenced. The present work indicates that co-presence of nanoplastics and ofloxacin has synergistic combined effects on community structure shifts, niche breadth shrinking, network simplifying, and differential prokaryotic pathways inducing in marine microbial communities, suggesting nanoplastics and its combined impacts with other pollutions should be paid with more concerns.


Asunto(s)
Microbiota , Ofloxacino , Ofloxacino/toxicidad , Microplásticos/toxicidad , Poliestirenos/toxicidad , Antibacterianos/toxicidad , Plancton
19.
Microorganisms ; 11(6)2023 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-37374924

RESUMEN

The genus Pleuronema Dujardin, 1841, with nearly 40 morphospecies, is one of the largest genera in the well-known subclass Scuticociliatia. In the present study, two Pleuronema species were collected from subtropical coastal waters of the East China Sea. The morphology and molecular phylogeny were investigated using modern standard methods. Pleuronema ningboensis n. sp. is mainly characterized by an elliptical body in outline with the right ventrolateral side straight, 16-22 somatic kineties, 3-5 preoral kineties, and the posterior end of the membranelle 2a hook-like. An improved diagnosis of Pleuronema orientale Pan et al., 2015 was provided: body size in vivo usually 90-135 × 45-85 µm, right ventrolateral side convex, 36-51 somatic kineties, 1-5 preoral kineties, one to three spherical macronuclei, membranelle 2a arranged in a zig-zag pattern in middle portion, posterior region hook-like, both membranelle 1 and membranelle 3 composed of three rows of basal bodies. The small subunit ribosomal DNA (SSU rDNA) of two species is sequenced, and their molecular phylogeny is analyzed. The new species Pleuronema ningboensis n. sp. clusters with P. grolierei KF840519, P. setigerum JX310015, P. paucisaetosum KF206430, and P. cf. setigerum KF848875, basically in accord with the morphological characteristics.

20.
Plants (Basel) ; 13(1)2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38202392

RESUMEN

This study examined the impacts of growth stage and ensiling duration on the fermentation characteristics, nitrite content, and bacterial communities during the ensiling of alfalfa. Harvested alfalfa was divided into two groups: vegetative growth stage (VG) and late budding stage (LB). The fresh alfalfa underwent wilting until reaching approximately 65% moisture content, followed by natural fermentation. The experiment followed a completely randomized design, with samples collected after the wilting of alfalfa raw materials (MR) and on days 1, 3, 5, 7, 15, 30, and 60 of fermentation. The growth stage significantly influenced the chemical composition of alfalfa, with crude protein content being significantly higher in the vegetative growth stage alfalfa compared to that in the late budding stage (p < 0.05). Soluble carbohydrates, neutral detergent fiber, and acid detergent fiber content were significantly lower in the vegetative growth stage compared to the late budding stage (p < 0.05). Nitrite content, nitrate content, nitrite reductase activity, and nitrate reductase activity were all significantly higher in the vegetative growth stage compared to the late budding stage (p < 0.05). In terms of fermentation parameters, silage from the late budding stage exhibited superior characteristics compared to that from the vegetative growth stage. Compared to the alfalfa silage during the vegetative growth stage, the late budding stage group exhibited a higher lactate content and lower pH level. Notably, butyric acid was only detected in the silage from the vegetative growth stage group. Throughout the ensiling process, nitrite content, nitrate levels, nitrite reductase activity, and nitrate reductase activity decreased in both treatment groups. The dominant lactic acid bacteria differed between the two groups, with Enterococcus being predominant in vegetative growth stage alfalfa silage, and Weissella being predominant in late budding stage silage, transitioning to Lactiplantibacillus in the later stages of fermentation. On the 3rd day of silage fermentation, the vegetative growth stage group exhibited the highest abundance of Enterococcus, which subsequently decreased to its lowest level on the 15th day. Correlation analysis revealed that lactic acid bacteria, including Limosilactobacillus, Levilactobacillus, Loigolactobacillus, Pediococcus, Lactiplantibacillus, and Weissella, played a key role in nitrite and nitrate degradation in alfalfa silage. The presence of nitrite may be linked to Erwinia, unclassified_o__Enterobacterales, Pantoea, Exiguobacterium, Enterobacter, and Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium.

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