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1.
Aquac Nutr ; 2023: 5545898, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36967811

RESUMEN

This study is aimed at establishing optimal soybean lecithin (SL) enrichment protocols in Artemia nauplii and at comparing the growth performance, body composition, and liver tissue metabolism in rock bream (Oplegnathus fasciatus) larvae reared on SL-enriched Artemia nauplii or SL-enriched microdiet (MD). The enrichment protocol experiment results indicated 12 h enrichment, and 10 g SL/m3 seawater could obtain desirable results. Rock bream larvae (25 days posthatching (dph)) were fed Artemia nauplii or MD for 30 days with three replicates. At stage 1 (larval 25-40 dph), significantly higher growth performance was observed in larvae fed the live prey (P < 0.05). Conversely, at stage 2 (41-55 dph), feeding with MD significantly increased larval standard length, and specific growth rate compared with those of larvae fed live prey. Larvae fed a MD showed decreased lipolysis-related lipase activity as well as decreased amino acid catabolism-related alanine aminotransferase and aspartate aminotransferase enzyme activities in liver tissue. RNA sequencing revealed that feeding with the MD primarily increased the expression of lipogenesis-related genes and protein translation-related gene expression in the liver tissue. Notably, feeding with MD significantly increased ribosome biogenesis-related genes as well as mitochondria synthesis-related gene expression, indicating a high protein anabolism rate and high energy production in liver tissue. In conclusion, 10 g SL/m3 seawater and 12 h could effectively enrich SL in Artemia nauplii. Retard weaning onto MD led to lower growth performance, which was likely due to the diversity of lipid and protein metabolism.

2.
Fish Physiol Biochem ; 49(6): 1277-1294, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37878190

RESUMEN

Production of sterile mono-sex fish is of great significance for sustainable aquaculture as well as germ cell transplantation. In this study, we aimed to produce mono-sex triploid yellow drum, including genotypic females (XXX female) and sex-reversed phenotypic males (XXX male). Firstly, the mono-female triploids were produced through cold-shock treatment on eggs fertilized with sperm from neo-males. Then, the mono-male triploids were produced by the sex reversal of mono-female triploids with oral administration of letrozole (LZ). We comparatively investigated the growth and gonadal development in the mono-sex triploids. The results showed that the triploids displayed similar growth performance to their diploids throughout their first year, but had impaired gonadosomatic index and gametogenesis. No mature gametes were produced in the triploids during their first spawning season. Meanwhile, we analyzed the process of gametogenesis in the both sex of triploids. Ultrastructure of gametogenesis showed that the germ cells arrested at abnormal metaphase 1 in females, while males had irregular meiotic divisions, variable-sized spermatid and degenerated cells. The expression levels of meiosis-related genes (i.e., sycp3 and rec8) confirmed the abnormal meiosis in the triploids. Furthermore, the gonadal development was also determined by the expression patterns of vasa, dmrt1 and cyp19a1a. Abnormal expression of vasa mRNA and protein were detected in triploids. High cyp19a1a expression levels suggested the sex steroid hormones production might be at least partially functional in triploid females. In addition, high dmrt1 expression levels confirmed the masculinization and testicular development of sex-reversed triploid males by LZ. Our findings provide an efficient protocol to produce sterile mono-sex triploid yellow drum and provide new insights into the mechanism of gonadal sterility of triploid fish.


Asunto(s)
Infertilidad , Perciformes , Masculino , Femenino , Animales , Triploidía , Semen , Gónadas , Gametogénesis , Peces , Perciformes/genética
3.
J Transl Med ; 20(1): 60, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35109880

RESUMEN

BACKGROUND: High intensity interval training (HIIT) has been reported to exert better effects on cardiovascular fitness in obesity, but little known about the arterial stiffness (AS) in female university students with normal weight obesity (NWO). Thus, this study aimed to investigate the effects of HIIT on the body composition, heart rate (HR), blood pressure (BP), blood lipids metabolism as well as the novel parameters of propensity for AS (arterial velocity pulse index [AVI], arterial pressure volume index [API]) for female university students with NWO. METHODS: Forty female university students with NWO were randomly assigned to control group (n = 20) and HIIT group (3 bouts of 9­min intervals at 90% of the maximal heart rate [HRmax], interspersed by 1 min rest, 5 days a week, n = 20). Tests were performed before and after 4 weeks of training. Repeated measures ANOVA and simple effect test analysis were used to analyze dependent variable changes. RESULTS: After 4 weeks HIIT statistically significantly improved the body composition by decreasing the body mass index, body fat percent, total body fat mass (BFM), BFM of left arm, measured circumference of left arm, and obesity degree, and increasing the total body skeletal muscle mass, protein content, total body water, fat free mass, body cell mas, and InBody score. HIIT also statistically significantly decreased the HR and BP. As for the lipid profile, HIIT obviously ameliorated the blood lipids metabolism by decreasing the levels of total cholesterol (TC), triglyceride, low-density lipoprotein, and TC/HDL, and increasing the levels of high-density lipoprotein (HDL). In addition, the AVI and API were markedly decreased via HIIT intervention. CONCLUSIONS: HIIT produced significant and meaningful benefits for body composition, HR, BP, and blood lipids metabolism, and could decrease AS in female university students with NWO. This suggests that HIIT may effectively reduce the risk of arteriosclerosis and protect the cardiovascular function for female university students with NWO. Trial registration ChiCTR2100050711. Registered 3 September 2021. Retrospectively registered.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Rigidez Vascular , China , Femenino , Humanos , Obesidad/metabolismo , Obesidad/terapia , Proyectos Piloto , Estudiantes , Universidades
4.
Proc Natl Acad Sci U S A ; 116(14): 7021-7026, 2019 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-30846553

RESUMEN

The opportunistic bacterial pathogen Pseudomonas aeruginosa has a layered acyl-homoserine lactone (AHL) quorum-sensing (QS) system, which controls production of a variety of extracellular metabolites and enzymes. The LasRI system activates genes including those coding for the extracellular protease elastase and for the second AHL QS system, RhlRI. Growth of P. aeruginosa on casein requires elastase production and LasR-mutant social cheats emerge in populations growing on casein. P. aeruginosa colonizes the lungs of individuals with the genetic disease cystic fibrosis (CF), and LasR mutants can be isolated from the colonized lungs; however, unlike laboratory-generated LasR mutants, many of these CF isolates have functioning RhlR-RhlI systems. We show that one such mutant can use the RhlR-RhlI system to activate expression of elastase and grow on casein. We carried out social-evolution experiments by growing this isolate on caseinate and, as with wild-type P. aeruginosa, elastase-negative mutants emerge as cheats, but these are not RhlR mutants; rather, they are mutants that do not produce the non-AHL Pseudomonas quinolone signal (PQS). Furthermore, we generated a RhlRI mutant and showed it had a fitness defect when growing together with the parent. Apparently, RhlR QS and PQS collude to support growth on caseinate in the absence of a functional LasR. Our findings provide a plausible explanation as to why P. aeruginosa LasR mutants, but not RhlR mutants, are common in CF lungs.


Asunto(s)
Acil-Butirolactonas/metabolismo , Proteínas Bacterianas/metabolismo , Pseudomonas aeruginosa/metabolismo , Percepción de Quorum , Transducción de Señal , Transactivadores/metabolismo , Proteínas Bacterianas/genética , Humanos , Pseudomonas aeruginosa/genética , Transactivadores/genética
5.
Opt Express ; 29(6): 8171-8180, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33820268

RESUMEN

Metal-dielectric low dispersion mirrors (MLDM) have a promising application prospect in petawatt (PW) laser systems. We studied the damage characteristics of MLDM and found that the damage source of MLDM (Ag + Al2O3+SiO2) is located at the metal-dielectric interface. We present the effect of the interface on the femtosecond laser damage of MLDM. Finite element analysis shows that thermal stress is distributed at the interface, causing stress damage which is consistent with the damage morphology. After enhancing the interface adhesion and reducing the residual stress, the damage source transfers from the interface to a surface SiO2 layer, and the damage threshold can be increased from 0.60 J/cm2 to 0.73 J/cm2. This work contributes to the search for new techniques to improve the damage threshold of MLDM used in PW laser systems.

6.
Opt Lett ; 46(21): 5336-5339, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34724469

RESUMEN

A low-dispersion mirror (LDM), an important component in ultrafast laser systems, requires both a broad low-dispersion laser-induced damage threshold (LIDT). It is difficult for a traditional quarter-wavelength-based dielectric LDM to achieve these characteristics at the same time. We propose a novel, to the best of our knowledge, low-dispersion mirror (NLDM) that combines periodic chirped layers at the top and alternating quarter-wavelength layers at the bottom. Low dispersion is achieved by introducing a large same group delay (GD) for different wavelengths, so the bandwidth is broadened greatly. In addition, owing to the staggered electric field intensity peak effect in the structure, the NLDM shows the potential for high laser damage resistance. The experiments demonstrated that the NLDM doubles the low-dispersion bandwidth, while the LIDT is also increased compared with the LDM. This novel concept results in improved performance and paves the way toward a new generation of the LDM for ultrafast bandwidth and a high laser applications.

7.
Int J Mol Sci ; 22(3)2021 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-33498889

RESUMEN

Chitosan and its derivative, chitosan oligosaccharide (CO), possess hypolipidemic and anti-obesity effects. However, it is still unclear if the mechanisms are different or similar between chitosan and CO. This study was designed to investigate and compare the effects of CO and high-molecular-weight chitosan (HC) on liver lipogenesis and lipid peroxidation, adipose lipolysis, and intestinal lipid absorption in high-fat (HF) diet-fed rats for 12 weeks. Rats were divided into four groups: normal control diet (NC), HF diet, HF diet+5% HC, and HF diet+5% CO. Both HC and CO supplementation could reduce liver lipid biosynthesis, but HC had a better effect than CO on improving liver lipid accumulation in HF diet-fed rats. The increased levels of triglyceride decreased lipolysis rate, and increased lipoprotein lipase activity in the perirenal adipose tissue of HF diet-fed rats could be significantly reversed by both HC and CO supplementation. HC, but not CO, supplementation promoted liver antioxidant enzymes glutathione peroxidase and superoxide dismutase activities and reduced liver lipid peroxidation. In the intestines, CO, but not HC, supplementation reduced lipid absorption by reducing the expression of fabp2 and fatp4 mRNA. These results suggest that HC and CO have different mechanisms for improving lipid metabolism in HF diet-fed rats.


Asunto(s)
Quitosano/farmacología , Dieta Alta en Grasa/efectos adversos , Metabolismo de los Lípidos/efectos de los fármacos , Obesidad/metabolismo , Tejido Adiposo/metabolismo , Animales , Quitosano/uso terapéutico , Absorción Intestinal , Peroxidación de Lípido , Lipogénesis , Lipólisis , Hígado/metabolismo , Masculino , Obesidad/tratamiento farmacológico , Obesidad/etiología , Ratas , Ratas Sprague-Dawley
8.
Mar Drugs ; 18(8)2020 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-32748864

RESUMEN

Chitosan oligosaccharide is known to ameliorate hypercholesterolemia and diabetes. However, some studies found that chitosan oligosaccharide might induce mild to moderate hepatic damage in high-fat (HF) diet-induced obese rats or diabetic rats. Chitosan oligosaccharide can be as a dietary supplement, functional food, or drug. Its possible toxic effects to normal subjects need to be clarified. This study is designed to investigate the effects of chitosan oligosaccharide on plasma and hepatic lipid metabolism and liver histomorphology in normal Sprague-Dawley rats. Diets supplemented with 5% chitosan oligosaccharide have been found to induce liver damage in HF diet-fed rats. We therefore selected 5% chitosan oligosaccharide as an experimental object. Rats were divided into: a normal control diet group and a normal control diet +5% chitosan oligosaccharide group. The experimental period was 12 weeks. The results showed that supplementation of 5% chitosan oligosaccharide did not significantly change the body weight, food intake, liver/adipose tissue weights, plasma lipids, hepatic lipids, plasma levels of AST, ALT, and TNF-α/IL-6, hepatic lipid peroxidation and anti-oxidative enzyme activities, fecal lipids, and liver histomorphology in normal rats. These findings suggest that supplementation of 5% chitosan oligosaccharide for 12 weeks may not induce lipid metabolism disorder and liver toxicity in normal rats.


Asunto(s)
Quitina/análogos & derivados , Suplementos Dietéticos , Hígado/efectos de los fármacos , Animales , Biomarcadores/sangre , Quitina/farmacología , Quitosano , Enzimas/sangre , Mediadores de Inflamación/sangre , Lípidos/sangre , Hígado/metabolismo , Oligosacáridos , Ratas Sprague-Dawley , Factores de Tiempo
9.
Appl Environ Microbiol ; 85(23)2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31540986

RESUMEN

The phytopathogen Dickeya zeae MS2 is a particularly virulent agent of banana soft rot disease. To begin to understand this banana disease and to understand the role of quorum sensing and quorum-sensing-related regulatory elements in D. zeae MS2, we sequenced its genome and queried the sequence for genes encoding LuxR homologs. We identified a canonical LuxR-LuxI homolog pair similar to those in other members of the genus Dickeya The quorum-sensing signal for this pair was N-3-oxo-hexanoyl-homoserine lactone, and the circuit affected motility, cell clumping, and production of the pigment indigoidine, but it did not affect infections of banana seedlings in our experiments. We also identified a luxR homolog linked to a gene annotated as encoding a proline iminopeptidase. Similar linked pairs have been associated with virulence in other plant pathogens. We show that mutants with deletions in the proline iminopeptidase gene are attenuated for virulence. Surprisingly, a mutant with a deletion in the gene encoding the LuxR homolog shows normal virulence.IMPORTANCEDickeya zeae is an emerging banana soft rot pathogen in China. We used genome sequencing and annotation to create an inventory of potential virulence factors and virulence gene regulators encoded in Dickeya zeae MS2, a particularly virulent strain. We created mutations in several genes and tested these mutants in a banana seedling infection model. A strain with a mutated proline iminopeptidase gene, homologs of which are important for disease in the Xanthomonas species phytopathogens, was attenuated for soft rot symptoms in our model. Understanding how the proline iminopeptidase functions as a virulence factor may lead to insights about how to control the disease, and it is of general importance as homologs of the proline iminopeptidase occur in dozens of plant-associated bacteria.


Asunto(s)
Gammaproteobacteria/fisiología , Gammaproteobacteria/patogenicidad , Factores de Virulencia/aislamiento & purificación , Dickeya , Musa/microbiología , Enfermedades de las Plantas/microbiología , Percepción de Quorum
10.
Opt Lett ; 44(24): 6053-6056, 2019 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32628219

RESUMEN

We report the feasibility of continuously tunable dispersion control with chirped mirrors (CMs). The concept of tunable second-order and higher-order dispersion is also proposed. Our prototype dispersion-tunable CM makes it possible to provide continuous dispersion support, advancing the CM technique to a new level by overcoming the drawback of the discrete dispersion compensation nature of traditional CMs. This brings extreme convenience and flexibility to the compensation of the dispersion and ensures tailored dispersion compensation in ultrafast laser systems. In our proof-of-concept study, continuously tunable group delay dispersion (GDD) is achieved by altering the angles of incidence on the mirrors. Moreover, continuous duration tunable laser pulses are demonstrated by applying our GDD-tunable CMs in an ultrafast laser system.

11.
Fish Shellfish Immunol ; 92: 341-347, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31202964

RESUMEN

The yellow drum (Nibea albiflora) is an economically important maricultured fish in China, but the aquaculture of this species has recently been limited by an increase in overwinter mortalities associated with cold and starvation stress due to global climate changes. To better understand the interaction between starvation and cold-stress-driven overwinter mortality, we investigated the effects of these stresses on the growth performance, liver lesions, and immune response of yellow drum fish. The fish were subjected to different cold treatments and under starvation stress. The experiment lasted 30 days and involved four experimental groups: a fed group and a fasted group maintained at 16 °C (control), and a fed group and a fasted group subjected to cold stress at 8 °C. We found that the growth of yellow drum was severely affected by cold temperatures and starvation. Throughout the experimental period, the body weights were significantly lower in the groups subjected to starvation and cold stress than in the control group. The liver cells showed irregular shapes and disorderly arrangements in the stress groups; indicating liver lesions. The gene expressions of antioxidant enzymes (copper, zinc superoxide dismutase, manganese superoxide dismutase, iron superoxide dismutase, and catalase) in the liver were lower in the groups subjected to starvation and cold stress than in the control groups. These results were basically consistent with the enzyme activities of superoxide dismutase and catalase tested in the livers. In addition, activities of immunomodulatory enzymes (alkaline phosphatase and acid phosphatase) were also inhibited in groups subjected to stress throughout the experiment period. These findings suggested that starvation and cold stress inhibited growth, depressed liver function, and suppressed the immune system of yellow drum, which likely would lead to physiological failure and increased susceptibility to infection. The present study offers insights into the physiological and immune response of yellow drum under cold and starvation stress. These insights not only provide baseline information from which effective strategies can be established and appropriate management decisions formulated, but can also be used to improve the overwinter survival of this important fish species in China.


Asunto(s)
Privación de Alimentos , Inmunidad Innata , Longevidad , Perciformes/inmunología , Animales , Frío/efectos adversos , Hígado/anatomía & histología , Hígado/fisiología , Perciformes/crecimiento & desarrollo
12.
Spine J ; 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38679076

RESUMEN

BACKGROUND: Cervical spinal cord injury usually results in cardiorespiratory dysfunctions due to interruptions of the bulbospinal pathways innervating the cervical phrenic motoneurons and thoracic sympathetic preganglionic neurons. PURPOSE: The present study aimed to evaluate the therapeutic effects of adrenergic agents on systemic and spinal hemodynamics during acute cervical spinal cord injury. STUDY DESIGN: In vivo animal study. METHODS: The cardiorespiratory function and spinal cord blood flow and oxygenation level were monitored in response to cervical spinal cord contusion and intravenous infusion of three types of adrenergic agents (phenylephrine, dobutamine, and norepinephrine). RESULTS: Cervical spinal cord contusion resulted in immediate reduction of respiratory airflow, arterial blood pressure, and spinal cord blood flow. The arterial blood pressure and spinal cord blood flow remained lower than the pre-injury value in contused animals infused with saline at 60 min post-injury. Infusion of phenylephrine (500, 1000, and 2000 µg/kg) and norepinephrine (125, 250, and 500 µg/kg) significantly increased the arterial blood pressure, while only norepinephrine augmented the spinal cord blood flow. Conversely, dobutamine (1000 and 2000 µg/kg) reduced both arterial blood pressure and spinal cord blood flow. Notably, administration of adrenergic agents tended to increase spinal cord hemorrhage in contused animals. CONCLUSIONS: Infusion of norepinephrine can effectively maintain the blood pressure and improve spinal cord blood flow during acute spinal cord injury. CLINICAL SIGNIFICANCE: Norepinephrine may be a superior medicine for hemodynamic management; however, the potential hemorrhage should be considered when utilizing the vasopressor to regulate systemic and spinal hemodynamics at the acute injured stage.

13.
Front Microbiol ; 14: 1256785, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37954251

RESUMEN

The Gram-negative opportunistic pathogen Pseudomonas aeruginosa possesses hierarchical quorum sensing (QS) systems. The intricate QS network of P. aeruginosa synchronizes a suite of virulence factors, contributing to the mortality and morbidity linked to the pathogenicity of this bacterium. Previous studies have revealed that variations in the lasR gene are frequently observed in chronic isolates of cystic fibrosis (CF). Specifically, LasRQ45stop was identified as a common variant among CF, lasR mutants during statistical analysis of the clinical lasR mutants in the database. In this study, we introduced LasRQ45stop into the chromosome of P. aeruginosa PAO1 through allelic replacement. The social traits of PAO1 LasRQ45stop were found to be equivalent to those of PAO1 LasR-null isolates. By co-evolving with the wild-type in caseinate broth, elastase-phenotypic-variability variants were derived from the LasRQ45stop subpopulation. Upon further examination of four LasRQ45stop sublines, we determined that the variation of T2SS-peptidase xcpA and mexT genes plays a pivotal role in the divergence of various phenotypes, including public goods elastase secretion and other pathogenicity traits. Furthermore, XcpA mutants demonstrated a fitness advantage compared to parent strains during co-evolution. Numerous phenotypic variations were associated with subline-specific genetic alterations. Collectively, these findings suggest that even within the same parental subline, there is ongoing microevolution of individual mutational trajectory diversity during adaptation.

14.
Heliyon ; 9(5): e16251, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37251882

RESUMEN

The preparation of slurry from multi-source solid waste for underground backfill adds a way out for solid waste disposal, which is beneficial to reduce environmental impact. In this paper, the effects of gangue, fly ash, gasification coarse slag and desulfurization gypsum on the fluidity, early strength, thermal stability and other properties of the backfill slurry were studied by fluidity test, strength test, Thermo-Gravimetric Analysis (TGA), Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD). The results show that: (1) When G/SW (mass ratio of gangue to solid waste) < 23%, gangue is beneficial to improve the fluidity and early strength of backfill slurry; with the increase of fly ash content, the fluidity of backfill slurry decreases, but its early strength increases; gasification coarse slag has a negative effect on the fluidity of backfill slurry, but it is beneficial to its early strength when GCS/SW (mass ratio of gasification coarse slag to solid waste) < 33%; desulfurization gypsum can improve the fluidity of the backfill slurry, but it is not conducive to the increase of early strength. (2) The compression failure mode of the backfill is mainly divided into the crack-intensive failure, the single main crack penetration splitting failure, and the double main crack conjugate splitting failure. (3) Endothermic dehydration reactions of adsorbed water and crystallization water generally occur at 55-65 °C and 110-130 °C for backfill with different solid waste contents; As the temperature continues to increase, the backfill material undergoes a slow exothermic decomposition reaction; Increasing the content of gangue, fly ash and gasification coarse slag and reducing the content of desulfurized gypsum can make the backfill less weight loss at high temperature and better thermal stability. (4) The main mineral phases in the backfill material are gypsum and quartz, and there are also a small amount of acicular and hexagonal hydration products thaumasite. After high temperature, the thaumasite is dehydrated and decomposed. The research results are helpful to deeply understand the performance of multi-source solid waste for underground backfilling.

15.
J Neural Eng ; 20(5)2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37666242

RESUMEN

Objective. Decoding memory functions for each hippocampal subregion involves extensive understanding of how each hippocampal subnetwork processes input stimuli. Theta burst stimulation (TBS) recapitulates natural brain stimuli which potentiates synapses in hippocampal circuits. TBS is typically applied to a bundle of axons to measure the immediate response in a downstream subregion like the cornu ammonis 1 (CA1). Yet little is known about network processing in response to stimulation, especially because individual axonal transmission between subregions is not accessible.Approach. To address these limitations, we reverse engineered the hippocampal network on a micro-electrode array partitioned by a MEMS four-chambered device with interconnecting microfluidic tunnels. The micro tunnels allowed monitoring single axon transmission which is inaccessible in slices orin vivo. The four chambers were plated separately with entorhinal cortex (EC), dentate gyrus (DG), CA1, and CA3 neurons. The patterned TBS was delivered to the EC hippocampal gateway. Evoked spike pattern similarity in each subregions was quantified with Jaccard distance metrics of spike timing.Main results. We found that the network subregion produced unique axonal responses to different stimulation patterns. Single site and multisite stimulations caused distinct information routing of axonal spikes in the network. The most spatially similar output at axons from CA3 to CA1 reflected the auto association within CA3 recurrent networks. Moreover, the spike pattern similarities shifted from high levels for axons to and from DG at 0.2 s repeat stimuli to greater similarity in axons to and from CA1 for repetitions at 10 s intervals. This time-dependent response suggested that CA3 encoded temporal information and axons transmitted the information to CA1.Significance. Our design and interrogation approach provide first insights into differences in information transmission between the four subregions of the structured hippocampal network and the dynamic pattern variations in response to stimulation at the subregional level to achieve probabilistic pattern separation and novelty detection.


Asunto(s)
Corteza Entorrinal , Estimulación Magnética Transcraneal , Hipocampo , Región CA1 Hipocampal , Axones
16.
J Biophotonics ; 16(10): e202300149, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37491832

RESUMEN

Optical-resolution photoacoustic microscopy suffers from narrow depth of field and a significant deterioration in defocused signal intensity and spatial resolution. Here, a method based on deep learning was proposed to enhance the defocused resolution and signal-to-noise ratio. A virtual optical-resolution photoacoustic microscopy based on k-wave was used to obtain the datasets of deep learning with different noise levels. A fully dense U-Net was trained with randomly distributed sources to improve the quality of photoacoustic images. The results show that the PSNR of defocused signal was enhanced by more than 1.2 times. An over 2.6-fold enhancement in lateral resolution and an over 3.4-fold enhancement in axial resolution of defocused regions were achieved. The large volumetric and high-resolution imaging of blood vessels further verified that the proposed method can effectively overcome the deterioration of the signal and the spatial resolution due to the narrow depth of field of optical-resolution photoacoustic microscopy.

17.
Mar Biotechnol (NY) ; 25(3): 403-414, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37162621

RESUMEN

Rock bream (Oplegnathus fasciatus) is a typical fish that has a unique multiple sex chromosome system (♀X1X1X2X2/♂X1X2Y). We examined the early gonadal development in rock bream via continuous histological observations of the gonads at 40-120 days post hatching (dph). The fish was identified as a typical gonochorist, and female gonads were found to differentiate earlier than male gonads. The ovarian cavity of the female was initially observed at 80 dph, whereas the efferent duct of the male was not observed until 100 dph. Immunofluorescence with the vasa-antibody revealed that germ cells were predominantly distributed around the ovarian cavity in females and on the edge of the gonad in males during the early stages of sex differentiation. Sex reversal was induced via the oral administration of letrozole (LTZ), 17α-methyltestosterone (MT), and 17ß-estradiol (E2), respectively, during the labile period of gonadal development. LTZ and MT induced 100% masculinization of genotype-females, whereas E2 induced only 50-60% feminization of genotype-males. Such findings suggest that the fish retained high sexual plasticity despite the existence of the neo-Y chromosome. MT and E2 had negative effect on fish growth, whereas LTZ did not exert such side effect. LTZ and MT could accelerate gonadal development in sex-reversed genotype-males, whereas E2 inhibited gonadal development in genotype-females of rock bream. These findings provide a basis for further research on the mechanisms of sex determination and differentiation in fishes with X1X2Y sex chromosome system and provide a sex reversal protocol for rock bream.


Asunto(s)
Peces , Gónadas , Testículo , Animales , Femenino , Masculino , Diferenciación Celular , Letrozol/farmacología , Metiltestosterona/farmacología , Diferenciación Sexual
18.
Front Immunol ; 14: 1296848, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38143747

RESUMEN

Soybean meal (SBM) is an acceptable replacement for unsustainable marine fish meal (FM) in aquaculture. However, we previously reported that high dietary SBM supplementation causes intestinal inflammatory injury in yellow drum (Nibea albiflora). Accordingly, a 4-week SBM-induced enteritis (SBMIE) in yellow drum trial was conducted first, followed by a 4-week additive-supplemented reparative experiment to evaluate the reparative effect of five additives on SBMIE in yellow drum. The control diet comprised 50% FM protein substituted with SBM. The additive-supplemented diet was added with 0.02% curcumin (SBMC), 0.05% berberine (SBM-BBR), 0.5% tea polyphenols (SBM-TPS), 1% taurine (SBM-TAU), or 0.8% glutamine (SBM-GLU) based on the control diet, respectively. The weight gain (WG), specific growth rate (SGR), feed efficiency ratio (FER), and survival rate (SR) of fish fed the additive-supplemented diets were significantly higher than those of fish fed the SBM diet. The WG, SGR, and FER of fish fed the SBMC, SBM-GLU and SBM-TAU diets were significantly higher than those of fish fed other diets. Moreover, fish fed the additive-supplemented diets SBMC and SBM-GLU, exhibited significantly increased intestinal villus height (IVH), intestinal muscular thickness (IMRT), and intestinal mucosal thickness (IMLT) and significantly decreased crypt depth (CD) in comparison with those fed the SBM diets. The relative expression of intestinal tight junction factors (ocln, zo1), cytoskeletal factors (f-actin, arp2/3), and anti-inflammatory cytokines (il10, tgfb) mRNA was remarkably elevated in fish fed additive-supplemented diets than those of fish fed the SBM diet. Whereas, the relative expression of intestinal myosin light chain kinase (mlck) and pro-inflammatory cytokines (il1, il6, tnfa) mRNA was markedly lower in fish fed the additive-supplemented diets. The highest relative expression of intestinal ocln, f-actin, and arp2/3 and the lowest relative expression of intestinal mlck were found in fish fed the SBMC diet. Hence, all five dietary additives effectively repaired the intestinal injury induced by SBM, with curcumin exhibiting the strongest repair effect for SBMIE in yellow drum.


Asunto(s)
Curcumina , Dieta , Enteritis , Perciformes , Animales , Actinas , Citocinas , Peces , Harina , ARN Mensajero
19.
Front Cardiovasc Med ; 10: 1083547, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37077735

RESUMEN

Atherosclerosis (AS) is the major form of cardiovascular disease and the leading cause of morbidity and mortality in countries around the world. Atherosclerosis combines the interactions of systemic risk factors, haemodynamic factors, and biological factors, in which biomechanical and biochemical cues strongly regulate the process of atherosclerosis. The development of atherosclerosis is directly related to hemodynamic disorders and is the most important parameter in the biomechanics of atherosclerosis. The complex blood flow in arteries forms rich WSS vectorial features, including the newly proposed WSS topological skeleton to identify and classify the WSS fixed points and manifolds in complex vascular geometries. The onset of plaque usually occurs in the low WSS area, and the plaque development alters the local WSS topography. low WSS promotes atherosclerosis, while high WSS prevents atherosclerosis. Upon further progression of plaques, high WSS is associated with the formation of vulnerable plaque phenotype. Different types of shear stress can lead to focal differences in plaque composition and to spatial variations in the susceptibility to plaque rupture, atherosclerosis progression and thrombus formation. WSS can potentially gain insight into the initial lesions of AS and the vulnerable phenotype that gradually develops over time. The characteristics of WSS are studied through computational fluid dynamics (CFD) modeling. With the continuous improvement of computer performance-cost ratio, WSS as one of the effective parameters for early diagnosis of atherosclerosis has become a reality and will be worth actively promoting in clinical practice. The research on the pathogenesis of atherosclerosis based on WSS is gradually an academic consensus. This article will comprehensively review the systemic risk factors, hemodynamics and biological factors involved in the formation of atherosclerosis, and combine the application of CFD in hemodynamics, focusing on the mechanism of WSS and the complex interactions between WSS and plaque biological factors. It is expected to lay a foundation for revealing the pathophysiological mechanisms related to abnormal WSS in the progression and transformation of human atherosclerotic plaques.

20.
J Appl Physiol (1985) ; 135(6): 1268-1283, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37855033

RESUMEN

Cervical spinal cord injury interrupts supraspinal pathways innervating thoracic sympathetic preganglionic neurons and results in cardiovascular dysfunction. Both respiratory and locomotor functions were also impaired due to damages of motoneuron pools controlling respiratory and forelimb muscles, respectively. However, no study has investigated autonomic and somatic motor functions in the same animal model. The present study aimed to establish a cervical spinal cord injury model to evaluate cardiorespiratory response and locomotor activity in unanesthetized rats. Cardiovascular response and respiratory behavior following laminectomy or cervical spinal contusion were measured using noninvasive blood pressure analyzer and plethysmography systems, respectively. Locomotor activity was evaluated by an open-field test and a locomotor rating scale. The results demonstrated that mean arterial blood pressure and heart rate were significantly reduced in contused rats compared with uninjured rats at the acute injured stage. Tidal volume was also significantly reduced during the acute and subchronic stages. Moreover, locomotor function was severely impaired, evidenced by decreasing moving ability and locomotor rating scores from the acute to chronic injured stages. Retrograde neurotracer results revealed that cervical spinal cord injury caused a reduction in number of phrenic and triceps motoneurons. Immunofluorescence staining revealed a significant attenuation of serotonergic, noradrenergic, glutamatergic, and GABAergic fibers innervating the thoracic sympathetic preganglionic neurons in chronically contused rats. These results revealed the pathological mechanism underlying the comorbidity of cardiorespiratory and locomotor dysfunction following cervical spinal cord injury. We proposed that this animal model can be used to evaluate the therapeutic efficacy of potential strategies to improve different physiological functions.NEW & NOTEWORTHY The present study establishes a preclinical rodent model to comprehensively investigate physiological functions under unanesthetized condition following cervical spinal cord contusion. The results demonstrated that cervical spinal cord contusion is associated with impairments in cardiovascular, respiratory, and locomotor function. Respiratory and forelimb motoneurons and neurochemical innervations of sympathetic preganglionic neurons were damaged following injury. This animal model can be used to evaluate the therapeutic efficacy of potential strategies to improve different physiological functions.


Asunto(s)
Médula Cervical , Traumatismos de la Médula Espinal , Ratas , Animales , Ratas Sprague-Dawley , Médula Cervical/lesiones , Médula Espinal , Comorbilidad , Vértebras Cervicales
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