Burst Activity Research Articles

Dietary Administration Effects of Microbial Exopolysaccharide from Bacillus subtilis P1 on Growth Performance and Immunity in Nile Tilapia (Oreochromis niloticus)

Exopolysaccharide (EPS)-producing bacteria were isolated from the intestines of freshwater fish as prebiotics. Among the isolates, Bacillus sp. P1 was the potent EPS producer, with a high EPS production, and was then identified as Bacillus subtilis P1 based on 16S rRNA and biochemical characteristics. The produced microbial EPS was characterized by its functional groups by FTIR, showing a 90.20% correlation to inulin, while the EPS molecular weight was approximately 105 Da with a high PDI (>1.5). Moreover, the EPS from B. subtilis P1 was assessed for prebiotic properties by growing probiotic bacteria, and significant cell growth occurred in sugar-free TSB with 0.5% EPS (p < 0.05). EPS exhibited approximately 55.37% DPPH radical scavenging at 20 mg/mL and inhibited certain fish pathogens at 400 μg/mL (10–13 mm inhibition zone). Low EPS cytotoxicity was confirmed (<1% hemolysis) prior to use as immunobiotics in Nile Tilapia (Oreochromis niloticus) diet supplementation. Nile tilapia growth and immune response were monitored after feeding with control (C), basal diet (BD), and treatment (T): BD + EPS 5 g/kg. In the T-group, the weight gain (WG), % specific growth rate (SGR), and average daily gain (ADG) significantly increased compared to the control (p < 0.05) by week 4, with no negative effects on blood chemistry parameters. Lysozyme activity and respiratory burst activity in T-groups were significantly higher than the control (p < 0.05), with a 50% RLP survival rate of Nile Tilapia infected by Aeromonas veronii in the T-group after a two-week challenge. On the other hand, the proximate analysis revealed higher protein content in the T-group. These findings suggest that EPS from B. subtilis P1 in fish diets efficiently supports fish growth and stimulates innate immune response in Nile Tilapia, thus showing potential as the immunobiotics for aquaculture.

Hematobiochemical Changes, Immunological Response and Immune Gene Expression in Nile Tilapia (Oreochrom niloticus) Experimentally Infected with Shewanella putrefaciens

Background: In this work, hematobiochemical changes, immunological responses, and histopathological changes in Nile tilapia (Oreochromis niloticus) experimentally infected with Shewanella putrefaciens were studied. Methods: O. niloticus was experimentally infected with S. putrefaciens (4SK/SRLFDA/19) at a concentration of 1.508×106CFU/ml per fish. Gross symptoms, namely hemorrhage on the body surface, skin discoloration, slow or nervous behavior, shallow necrotizing ulcers on the skin, fin erosions and abdominal distension were observed 5 to 6 days after infection. Fish were anesthetized and blood samples were collected at 0, 2, 4, 7, 10, 14, 20 and 27 days after the experimental infection to assess the hematobiochemical and immunological responses. For haematobiochemical responses, tests that included hemoglobin (Hb), leukocyte count (Lc), erythrocyte, hematocrite (Ht), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), cholesterol (CHO), glucose (GLU) and triglyceride were assessed. Result: Values of hematocrit, hemoglobin, albumin, globulin, erythrocyte, MCHC, cholesterol and triglyceride were significantly (p less than 0.05) decreased. Lc, MCV, MCH, and glucose values were significantly (p less than 0.05) increased. Respiratory burst activity (RBA) and serum total protein values were significantly (p less than 0.05) decreased. Relative expression of immune gene toll like receptor 4 (TLR4), stress genes heat shock proteins 70, 90 (HSP70, HSP90), oxidative stress gene glutathione S-transferases (GST) and inflammatory gene interleukin 6 (IL6) was significantly higher in experimentally infected fishes compared to control.

Growth performance, immunological, and biochemical responses of stinging catfish, (Heteropneustes fossilis) fingerlings reared in a biofloc-based production system

ABSTRACT A study was conducted to compare the high-density rearing of stinging catfish (Heteropneustes fossilis) fingerlings in both a control system and a biofloc system over 100 days. In the biofloc system, probiotics and a carbon source were added, while the control group had no additions. The biofloc system showed significantly (p < .05) higher floc volume (8.34 ± 1.33 ml L−1) and improvements in growth performance, survival rate, and biomass yield. Fingerlings reared in the biofloc system had increased digestive, oxidative enzyme activities and a lower feed conversion ratio. No changes were observed in the whole-body proximate composition between the groups. However, nonspecific immune responses, such as lysozyme and myeloperoxidase, were relatively improved, and other immune parameters like respiratory burst activity and total serum immunoglobulin were significantly increased in the biofloc system. In conclusion, biofloc-based rearing significantly enhanced the growth performance, feed utilization, and immunological conditions of stinging catfish.

Cortical, striatal, and thalamic populations self-organize into a functionally connected circuit with long-term memory properties

The human brain is a complex organ with an intricate neuronal connectivity and diverse functional regions. Neurological disorders often disrupt the delicate balance among these anatomical compartments, resulting in severe impairments. The available therapeutic options constitute an incomplete solution as many patients respond partially, highlighting the need for continued research into causes and treatments. Bottom-up approaches, like in vitro models, offer insights into brain functions as they recreate the in vivo microenvironment that allows studying how specific features affect physiological and pathological conditions. In this work, we engineered the cortical-striatal-thalamic (CST) circuit, involved in many brain functions such as action initiation and selection, using a three-compartment polymeric device. We characterized the emerging spontaneous electrophysiological activity by using Micro-Electrode Arrays (MEAs). Cortical neurons exhibited complex bursting activity, which influenced the entire circuit. Striatal and thalamic neurons displayed predominantly tonic firing when isolated, while interconnections with the cortex synchronized and organized their neuronal activity, highlighting the cortical pivotal role in bursting activity and information processing. The CST circuit demonstrated self-organization abilities and displayed high entropy values, indicative of dynamic richness and information encoding potential. Furthermore, we proved the CST’s involvement in learning and memory. Our CST model provides a platform for further exploration into brain circuitry and potential therapeutic interventions, underscoring the necessity of realistic in vitro models to fully understand neurological diseases' pathophysiology.

Neuronal sequences in population bursts encode information in human cortex.

Neural coding has traditionally been examined through changes in firing rates and latencies in response to different stimuli1-5. However, populations of neurons can also exhibit transient bursts of spiking activity, wherein neurons fire in a specific temporal order or sequence6-8. The human brain may utilize these neuronal sequences within population bursts to efficiently represent information9-12, thereby complementing the well-known neural code based on spike rate or latency. Here we examined this possibility by recording the spiking activity of populations of single units in the human anterior temporal lobe as eight participants performed a visual categorization task. We find that population spiking activity organizes into bursts during the task. The temporal order of spiking across the activated units within each burst varies across stimulus categories, creating unique stereotypical sequences for individual categories as well as for individual exemplars within a category. The information conveyed by the temporal order of spiking activity is separable from and complements the information conveyed by the units' spike rates or latencies following stimulus onset. Collectively, our data provide evidence that the human brain contains a complementary code based on the neuronal sequence within bursts of population spiking to represent information.

Schizophrenia pathology reverse-translated into mouse shows hippocampal hyperactivity, psychosis behaviors and hyper-synchronous events.

Decades of research into the function of the medial temporal lobe has driven curiosity around clinical outcomes associated with hippocampal dysfunction, including psychosis. Post-mortem analyses of brain tissue from human schizophrenia brain show decreased expression of the NMDAR subunit GluN1 confined to the dentate gyrus with evidence of downstream hippocampal hyperactivity in CA3 and CA1. Little is known about the mechanisms of the emergence of hippocampal hyperactivity as a putative psychosis biomarker. We have developed a reverse-translation mouse to study critical neural features. We had previously studied a dentate gyrus (DG)-specific GluN1 KO, which displays hippocampal hyperactivity and a psychosis-relevant behavioral phenotype. Here, we expressed an inhibitory DREADD (pAAV-CaMKIIa-hM4D(Gi)-mCherry) in granule cells of the mouse dentate gyrus, and continuously inhibited the region for 21 days in adolescent (6 weeks) and adult (10 weeks) C57BL/6 J mice with DREADD agonist Compound 21 (C21). Following this period, we quantified activity in the hippocampal subfields by assessing cFos expression, hippocampally mediated behaviors, and hippocampal local field potential with an intracerebral probe with continual monitoring over time. DG inhibition during adolescence generates an increase in hippocampal activity in CA3 and CA1, impairs social cognition and spatial working memory, as well as shows evidence of increased activity in local field potentials as spontaneous synchronous bursts of activity, which we term hyper-synchronous events (HSEs) in hippocampus. The same DG inhibition delivered during adulthood in the mouse lacks these outcomes. These results suggest a sensitive period in development in which the hippocampus is susceptible to DG inhibition resulting in hippocampal hyperactivity and psychosis-like behavioral outcomes.

Pallidal neuronal activity in Gilles de la Tourette syndrome and dystonic patients: A comparative study.

Gilles de la Tourette syndrome (GTS) and dystonia (DYS) are both hyperkinetic movement disorders effectively treated by deep brain stimulation (DBS) of the internal part of the globus pallidus (GPi). In this study, we compared single-neuron activity in the GPi between 18 GTS patients (with an average of 41 cells per patient) and 17 DYS patients (with an average of 54 cells per patient), all of whom underwent bilateral pallidal stimulation surgery, under general anesthesia or while awake at rest. We found no significant differences in GPi neuronal activity characteristics between patients operated on under general anesthesia versus those who were awake, irrespective of their diagnosis (GTS or DYS). We found higher firing rates, firing rate in bursts, pause duration and interspike interval coefficient of variation in GTS patients compared to DYS patients. On the opposite, we found higher number of pauses and bursts frequency in DYS patients. Lastly, we found a higher proportion of GPi oscillatory activities in DYS compared to GTS patients, with predominant activity within the low-frequency band (theta/alpha) in both patient groups. These findings underscore the complex relationship between the different neuronal discharge characteristic such as oscillatory or bursting activity within the GPi in shaping the clinical phenotypes of hyperkinetic disorders. Further research is warranted to deepen our understanding of how neuronal patterns are transmitted within deep brain structures and to develop strategies aimed at normalizing these pathological activities, by refining DBS techniques to enhance treatment efficacy and individual outcomes.

Relationship between regional sympathetic vascular transduction and sympathetic transduction of blood pressure in young adults at rest.

A burst of muscle sympathetic nerve activity (MSNA) induces vasoconstriction that transiently reduces regional vascular conductance and increases systemic blood pressure (BP) over the subsequent 4-8 cardiac cycles. These responses are termed sympathetic neurovascular transduction and sympathetic transduction of BP, respectively. Sympathetic transduction of BP is commonly calculated and interpreted as a proxy measure for regional sympathetic neurovascular transduction, despite the systemic nature of BP regulation. The present analysis tested whether the peak change in signal-averaged sympathetic transduction of BP was correlated to the change in regional sympathetic vascular transduction at rest. Fourteen adults (5 females, 23±3 years) arrived at the laboratory, ate a standardized meal, and rested for 90-120 minutes. MSNA (fibular nerve microneurography), heart rate (electrocardiography), beat-to-beat BP (finger photoplethysmography), and superficial femoral artery blood flow (Doppler ultrasound) were obtained continuously for 10 minutes in the supine position. Femoral vascular conductance was calculated as blood flow divided by mean arterial BP. The peak change in diastolic BP following a burst of MSNA was correlated to the corresponding nadir change in femoral vascular conductance (r=-0.58 [-0.07 to -0.85], P=0.03) and superficial femoral artery blood flow (r=-0.54 [-0.17 to -0.83], P=0.04). The nadir change in diastolic BP in cardiac cycles not following a MSNA burst was correlated to the peak change in femoral vascular conductance (r=-0.42 [-0.83 to 0.00], p=0.05) but not superficial femoral artery blood flow (r=0.41 [-0.77 to 0.15], p=0.14). In conclusion, more commonly assessed sympathetic transduction of BP provides moderate insight into regional sympathetic neurovascular transduction.

Right-left sEMG burst synchronization of the lumbar erector spinae muscles of seated violin players

Burst-like activation of postural muscles has been previously described and plays a crucial role in elucidating the strategies for postural control adopted by the central nervous system (CNS). A spatio-temporal descriptor of surface electromyographic (sEMG) bursts (STB) is proposed and applied to statistically quantify the burst-like activity of the right and left (R-L) lumbar erector spinae muscle of nine seated violinists playing for two hours. The STB signal is the number of pixels of the high density sEMG (HDsEMG) maps simultaneously showing sEMG amplitude above a given threshold. Burst activity was present in all nine subjects. Four of them met four stringent criteria allowing analysis of frequency, duration, and synchronization between the R-L bursts after 0, 15, 30, 60, 120 min of playing. Mean square coherence between STBs of the two muscles was > 0.75 within ⁓1 Hz bandwidth between 2.2 Hz and 4.5 Hz depending on subject. Non-parametric statistics was applied to compare, in time and space, the R-L features of the bursts. The mean STB width was significantly associated primarily to side and secondarily to time and ranged from 100 to 250 ms. The right STB signals led the left (p < 0.02) by 0 - 160 ms.The inverted pendulum composed by the upper body of a seated violinist is controlled in an intermittent way. The erector spinae of the selected subjects were active, on average, for less than 50% of the time. These findings demonstrate a CNS strategy of intermittent back muscle activation presumably aimed to reducing fatigue during hours of playing in seated violinists.

Classifying High-Frequency Oscillations by Morphologic Contrast to Background, With Surgical Outcome Correlates.

Ictal high-frequency oscillations (HFOs) are a reliable indicator of a seizure onset zone for intracranial EEG recordings. Interictal HFOs often are also observed and may be a useful biomarker to supplement ictal data, but distinguishing pathologic from physiologic HFOs continues to be a challenging task. We present a method of classifying HFOs based on morphologic contrast to the background. We retrospectively screened 31 consecutive patients who underwent intracranial recordings for epilepsy at Stanford Medical Center during a 2-year period, and 13 patients met the criteria for inclusion. Interictal EEG data were analyzed using an automated event detector followed by morphologic feature extraction and k-means clustering. Instead of only using event features, the algorithm also incorporated features of the background adjacent to the events. High-frequency oscillations with higher morphologic contrast to the background were labeled as pathologic, and "hotspots" with the most active pathologic HFOs were identified and compared with clinically determined seizure onset zones. Clustering with contrast features produced groups with better separation and more consistent boundaries. Eleven of the 13 patients proceeded to surgery, and patients whose hotspots matched seizure onset zones had better outcomes, with 4 out of 5 "match" patients having no disabling seizures at 1+ year postoperatively (Engel I or International League Against Epilepsy Class 1-2), while all "mismatch" patients continued to have disabling seizures (Fisher exact test P-value = 0.015). High-frequency oscillations with higher contrast to background more likely represent paroxysmal bursts of pathologic activity. Patients with HFO hotspots outside of identified seizure onset zones may not respond as well to surgery.

The Northern Cross Fast Radio Burst project

Context. Fast radio bursts (FRBs) are energetic, millisecond-duration radio pulses observed at extragalactic distances and whose origins are still a subject of heated debate. A fraction of the FRB population have shown repeating bursts, however it’s still unclear whether these represent a distinct class of sources. Aims. We investigated the bursting behaviour of FRB 20220912A, one of the most active repeating FRBs known thus far. In particular, we focused on its burst energy distribution, linked to the source energetics, and its emission spectrum, with the latter directly related to the underlying emission mechanism. Methods. We monitored FRB 20220912A at 408 MHz with the Northern Cross radio telescope and at 1.4 GHz using the 32-m Medicina Grueff radio telescope. Additionally, we conducted 1.2 GHz observations taken with the upgraded Giant Meter Wave Radio Telescope (uGMRT) searching for a persistent radio source coincident with FRB 20220912A, and included high energy observations in the 0.3–10 keV, 0.4–100 MeV and 0.03–30 GeV energy range. Results. We report 16 new bursts from FRB 20220912A at 408 MHz during the period between October 16th 2022 and December 31st 2023. Their cumulative spectral energy distribution follows a power law with slope αE = −1.3 ± 0.2 and we measured a repetition rate of 0.19 ± 0.03 hr−1 for bursts having a fluence of ℱ ≥ 17 Jy ms. Furthermore, we report no detections at 1.4 GHz for ℱ ≥ 20 Jy ms. These non-detections imply an upper limit of β &lt; −2.3, with β being the 408 MHz – 1.4 GHz spectral index of FRB 20220912A. This is inconsistent with positive β values found for the only two known cases in which an FRB has been detected in separate spectral bands. We find that FRB 20220912A shows a decline of four orders of magnitude in its bursting activity at 1.4 GHz over a timescale of one year, while remaining active at 408 MHz. The cumulative spectral energy distribution (SED) shows a flattening for spectral energy Eν ≥ 1031 erg Hz−1, a feature seen thus far in only two hyperactive repeaters. In particular, we highlight a strong similarity between FRB 20220912A and FRB 20201124A, with respect to both the energy and repetition rate ranges. We also find a radio continuum source with 240 ± 36 μJy flux density at 1.2 GHz, centered on the FRB 20220912A coordinates. Finally, we place an upper limit on the γ to radio burst efficiency η to be η &lt; 1.5 × 109 at 99.7% confidence level, in the 0.4–30 MeV energy range. Conclusions. The strong similarity between the cumulative energy distributions of FRB 20220912A and FRB 20201124A indicate that bursts from these sources are generated via similar emission mechanisms. Our upper limit on β suggests that the spectrum of FRB 20220912A is intrinsically narrow-band. The radio continuum source detected at 1.2 GHz is likely due to a star formation environment surrounding the FRB, given the absence of a source compact on millisecond scales brighter than 48 μJy beam−1. Finally, the upper limit on the ratio between the γ and radio burst fluence disfavours a giant flare origin for the radio bursts unlike observed for the Galactic magnetar SGR 1806-20.

A bibliometric analysis of alternative drug therapy options in the treatment of androgenetic alopecia.

Oral finasteride and topical minoxidil formulations are the only FDA-approved drug therapies for androgenetic alopecia (AGA). Research into dutasteride, topical finasteride, and nontopical minoxidil (low-dose oral and sublingual) formulations in the treatment of AGA has spiked within recent years. Early findings show that these alternative drug therapies may have similar to improved efficacy and safety profiles relative to the conventional treatment options. Conducting a bibliometric analysis, compare trends in publications on these alternative drug therapies, identify key contributors, evaluate major findings from top-cited articles, and elucidate gaps in evidence. A search was conducted on the Web of Science database for publications on the use of alternative drug therapies in the treatment of AGA. A total of 95 publications, published between January 2003-March 2024, and their citation metadata were included in the analysis. Dutasteride showed the greatest (n = 37) and longest (20+ years) history of publications, as well as the highest cumulative citations (n = 914); however, nontopical minoxidil showed a burst in research activity within the last 5 years (n = 33 publications since 2019). A relatively low number of randomized control trials (n = 3) for nontopical minoxidil suggests a need for higher-quality evidence. Our analysis reveals major trends, contributors, and gaps in evidence for alternative drug therapies for AGA, which can help inform researchers on their future projects in this growing field of study. There is enthusiasm for exploring off-label formulations: nontopical forms of minoxidil (oral and sublingual), topical finasteride, and mesotherapy.

Immunological, Antioxidant, Growth Responses, and Disease Resistance of Rainbow Trout, Oncorhynchus mykiss, with Feeding Diets Supplemented with Lactobacillus salivarius and Lutein

Abstract The aim of the present study was to assess the effects of dietary supplementation with Lactobacillus salivarius (LS) ATCC 11741 and lutein (LU) on immunological, antioxidant, and growth responses, and resistance against Yersinia ruckeri infection in rainbow trout (Oncorhynchus mykiss). There were seven experimental diets containing un-supplemented diet (CTL), L. salivarius at 1 × 106 (LS6) and 1 × 108 (LS8) CFU/g, lutein at 50 (LU50) and 150 (LU150) mg/kg, L. salivarius at 1 × 106 CFU/g plus lutein at 50 g/kg (LS6+LU50), and L. salivarius at 1 × 108 CFU/g plus lutein at 150 g/kg (LS8+LU150). These diets were provided to the fish (N= 735; 14.0±0.38 g). After 60 days of feeding, all experimental treatments exhibited significantly higher growth performance, compared to the CTL treatment. The intestinal protease activity and the intestinal lactic acid bacteria population in the probiotic-treated fish were significantly higher than in the CTL fish. The intestinal lipase activity was only higher in the LS6+LU50 treatment, compared to the CTL treatment. Compared to the CTL treatment, the intestinal total bacterial count, and serum superoxide dismutase significantly increased in the LS6+LU50 and LS8+LU150 treatments. The serum catalase significantly increased in LU150, LS6+LU50, and LS8+LU150 treatments, and serum glutathione peroxidase significantly increased in the lutein-treated fish. All experimental treatments, particularly LS6+LU50 and LS8+LU150, had significantly lower serum malondialdehyde levels, compared to the CTL treatment. The levels of serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase in LU50, LS6+LU50, and LS8+LU150 treatments were significantly lower than the CTL. All experimental treatments showed significantly higher serum lysozyme (LYZ), complement, blood respiratory burst activity (RB), and skin mucus alkaline phosphatase (ALP), compared to the CTL treatment. The highest serum LYZ, C4, total immunoglobulin (Ig), blood RB activity, and skin mucus peroxidase, ALP, and Ig were observed in the LS6+LU50 and LS8+LU150 treatments. All the experimental treatments, especially LS6+LU50, exhibited significantly lower mortality after the bacterial challenge compared to the CTL. In conclusion, dietary supplementation with 1 × 106 CFU/g L. salivarius and 50 mg/kg lutein can maximally improve growth performance, digestive enzymes, antioxidant parameters, immune responses, intestinal lactic acid bacteria, and resistance against yersiniosis in rainbow trout.

Arginine alleviates LPS-induced leukocytes inflammation and apoptosis via adjusted NODs signaling

Arginine plays a key role in regulating the immune function of fish. To evaluate the effect of arginine on the immune response of largemouth bass (Micropterus salmoides), the effects of arginine on cell viability, NADPH oxidase activity, respiratory burst activity, and NO production of leukocytes were analyzed both in vitro and in vivo. In this study, we found that arginine could promote the respiratory burst activity of leucocytes both in vivo and in vitro. By incubating leukocytes with the combination of LPS and arginine, we found that arginine supplementation inhibited the expression of inflammatory genes (tumor necrosis factor-alpha, tnfα; interleukin(il) 8 and il10) and apoptotic genes (caspase3, caspase8, and caspase9) induced by LPS, as well as promoted the arginine metabolism. Arginine supplementation significantly induced (cd4-like)cd4 gene expression after LPS challenge. Further studies showed that LPS could significantly increase nucleotide-binding oligomerization domain containing 1 (nod1) gene expression, but decreased the nod2 gene. The arginine supplementation increased nuclear factor kappa-B (NF-κB) protein level. In conclusion, arginine can alleviate LPS-induced inflammatory response and apoptosis as well as induce cd4 gene expression against LPS challenge via adjusting the expression of NODs signaling.

Dietary Chitosan Nanoparticles Enhance Growth, Antioxidant Defenses, Immunity, and Aeromonas veronii biovar sobria Resistance in Nile tilapia Oreochromis niloticus

While chitosan is widely used in aquaculture feed, chitosan nanoparticles (CNPs) offer potential advantages due to their enhanced absorption. This study investigated the safe use of CNP levels in Nile tilapia feed, evaluating its impact on growth, immunity, and disease resistance. Five experimental diets were formulated and supplemented with zero chitosan (served as a control group), 1g/kg of chitosan (CS), and 1, 3, and 5 g/kg of CNPs. Each diet was randomly assigned to three replicate groups of 45 fish per group (15 fish/tank) with an average weight of (42.10 ± 0.05g, mean ± S.E.) twice daily (09:00 a.m. and 4:00 p.m.) to apparent satiation for two months. At the end of the feeding trial, fish fed 5 g/ kg of CNPs had the highest growth performance. However, no significant variations (p &gt; 0.05) in somatic index were seen between the experimental groups. All chitosan and CNP-enriched groups exhibited improved intestinal morphology compared to the control group, characterized by increased villus length and width, reduced necrosis of intestinal tips, and better overall tissue integrity, with the CNP 3g and 5g groups demonstrating the most favorable intestinal structure. The CNP-treated groups (3, 5 g/kg) had significantly higher blood indices and serum globulin. Malondialdehyde (MDA) levels were lower in the CNP-treated groups compared to the chitosan macromolecule group. There was a substantial rise in glutathione (GSH), total antioxidant capacity (TAC), phagocytic index, and respiratory burst activity in the 5 g/kg CNP-treated group. The dietary addition of 5 g/kg of CNPs raised mRNA expression for TLR-2, MUC-2, and IGF-1, but there was no significant difference in HSP70 expression across treatments. After the experimental challenge with Aeromonas veronii biovar sobria, the groups that received 3 and 5 g/kg of CNPs exhibited the lowest mortality rates. Overall, the results suggest that including 5g/kg of CNPs in fish food is safe and effective for enhancing their health and growth, making it a promising addition to aquaculture feed.

Gut microbiome and metabolites mediate the benefits of caloric restriction in mice after acute kidney injury

The role of gut microbiome in acute kidney injury (AKI) is increasing recognized. Caloric restriction (CR) has been shown to enhance the resistance to ischemia/reperfusion injury to the kidneys in rodents. Nonetheless, it is unknown whether intestinal microbiota mediated CR protection against ischemic/reperfusion-induced injury (IRI) in the kidneys. Herein, we showed that CR ameliorated IRI-elicited renal dysfunction, oxidative stress, apoptosis, and inflammation, along with enhanced intestinal barrier function. In addition, gut microbiota depletion blocked the favorable effects of CR in AKI mice. 16S rRNA and metabolomics analysis showed that CR enriched the gut commensal Parabacteroides goldsteinii (P. goldsteinii) and upregulated the level of serum metabolite dodecafluorpentan. Intestinal colonization of P. goldsteinii and oral administration of dodecafluorpentan showed the similar beneficial effects as CR in AKI mice. RNA sequencing and experimental data revealed that dodecafluorpentan protected against AKI-induced renal injury by antagonizing oxidative burst and NFκB-induced NLRP3 inflammasome activation. In addition, we screened and found that Hamaudol improved renal insufficiency by boosting the growth of P. goldsteinii. Our results shed light on the role of intestinal microbiota P. goldsteinii and serum metabolites dodecafluorpentan in CR benefits to AKI.

Can incidental physical activity offset the deleterious associations of sedentary behaviour with major adverse cardiovascular events?

Incidental physical activity as part of daily living may offer feasibility advantages over traditional exercise. We examined the joint associations of incidental physical activity and sedentary behaviour with major adverse cardiovascular events (MACE) risk. Analyses included 22,368 non-exercising adults from the UK Biobank accelerometry sub-study (Median age [IQR]: 62.9 [11.6] years; 41.8% male). Physical activity and sedentary behaviour exposures were derived using a machine learning-based intensity and posture classification schema. We assessed the tertile-based joint associations of sedentary behaviour and: a) incidental vigorous (VPA), b) incidental moderate to vigorous (MVPA), c) vigorous intermittent lifestyle physical activity (VILPA; bouts lasting up to 1 minute), and d) moderate to vigorous intermittent lifestyle physical activity (MV-ILPA; bouts lasting up to 3 minutes) with MACE risk. Over an 8.0-year median follow-up, 819 MACE events occurred. Compared to the highest physical activity and lowest sedentary time, high sedentary behaviour (>11.4 hours/day) with low incidental VPA (<2.1 minutes/day) had an HR of 1.34 (95% CI: 0.98, 1.84) and low incidental MVPA (<21.8 minutes/day) had a 1.89 HR (95% CI: 1.42, 2.52) for MACE. Sedentary behaviour was not associated with MACE at medium and high levels of VPA or VILPA. Completing 4.1 minutes/day of VPA or VILPA may offset the MACE risk associated with high sedentary behaviour. Conversely, 31-65 minutes of incidental MVPA or 26-52 minutes of MV-ILPA per day largely attenuated the associations with MACE. Brief intermittent bursts of vigorous incidental physical activity may offset cardiovascular risks from high sedentary behaviour.

Effects of Locus Coeruleus Activation on n-Back Performance and Frontoparietal Activity.

Previous studies have linked working memory capacity to restricted hemodynamic responses within critical nodes of the frontoparietal network. Emerging evidence suggests a potential role of the locus coeruleus (LC) in modulating activation of key regions essential for working memory function. This study investigated this hypothesis by examining changes in BOLD signal within the LC and cortex during a parametrically designed verbal working memory task (n-back). fMRI revealed load-dependent task activation, with maximum activation of presumed LC neurons positively correlating with working memory capacity. Furthermore, increased hemodynamic responses in the superior parietal lobes and dorsolateral pFC corresponded with the magnitude of LC activation near working memory capacity limits. An exploratory functional connectivity analysis suggests improvements in working memory performance rely on negative functional connectivity between the LC and cortical regions not primarily involved in task completion. On the basis of previous evidence, this association may represent inhibitory input from cortical regions, enabling phasic bursts of activity from LC neurons, thereby facilitating enhanced cortical activation. This result may also indicate noradrenergic suppression of cortical regions that are not crucial for task completion, leading to enhanced network efficiency. These findings suggest a mechanism by which the LC may improve verbal working memory performance by facilitating enhanced activation in regions critical for visual working memory capacity and active maintenance, potentially enhancing network efficiency.

Influence of pegylated graphene oxide nanoparticles on the respiratory burst and phagocytic activity of human neutrophils

Scientific and technological progress contributes to the discovery and production of innovative materials. The emergence of graphene is a clear example of this. Graphene is considered a promising material for use in nanobiomedicine and nanobiotechnology. It is therefore important to understand how it affects human immune cells. In a study, the effects of 5 and 25 μg/mL graphene oxide nanoparticles with lateral sizes of 100-200 nm and 1-5 μm, modified with linear and branched polyethylene glycol, on human neutrophils were investigated. The formation of reactive oxygen species was evaluated with a lucigenin as a chemiluminescence activator.Inaddition, we investigated theeffect of a 60-minute incubation of neutrophils with pegylated graphene oxide nanoparticles on the viability of these cells by staining with trypan blue and a 30-minute incubation on the uptake of fluorescein isocyanate-labelled E. coli. The percentage of neutrophils which engulfed E. coli and the uptake index were determined. Samples without added nanoparticles served as controls.A decrease in lucigenin-enhanced chemiluminescence of neutrophils was observed under the influence of two types of graphene oxide nanoparticles: 1-5 μm in size coated with linear polyethylene glycol, and 100-200 nm in size coated with branched polyethylene glycol, at a concentration of 25 μg/mL in the zymosan-stimulated version of the assay. No dependence of the effect on the particle size and the type of polyethylene glycol was observed. The indicators for spontaneous chemiluminescence of neutrophils did not change with the addition of PEGylated graphene oxide nanoparticles.A thirty-minute incubation of human neutrophils at 37 °C with PEGylated graphene oxide nanoparticles with lateral dimensions of 100-200 nm and 1-5 μm had no effect on the viability of these cells and on the percentage of neutrophils that engulfed E. coli. However, 1-5 μm graphene oxide modified with linear polyethylene glycol at a concentration of 25 μg/mL increased the amount of E. coli engulfed by neutrophils per cell.Thus, in the absence of cytotoxicity, PEGylated graphene oxide particles have multidirectional immunomodulatory effects on neutrophils. In this case, their concentration is decisive and not the size of the graphene oxide particles and the type of polyethylene glycol.

Interaction of motor behaviour, cortical oscillations and deep brain stimulation in Parkinson disease

Abstract Recent progress in the study of Parkinson's disease (PD) has highlighted the pivotal role of beta oscillations within the basal ganglia-thalamo-cortical network in modulating motor symptoms. Predominantly manifesting as transient bursts, these beta oscillations are central to the pathophysiology of PD motor symptoms, especially bradykinesia. Our central hypothesis is that increased bursting duration in cortex, coupled with kinematics of movement, disrupts the typical flow of neural information, leading to observable changes in motor behavior in PD. To explore this hypothesis, we employed an integrative approach, analyzing the interplay between moment-to-moment brain dynamics and movement kinematics, and the modulation of these relationships by therapeutic deep brain stimulation (DBS). Local field potentials were recorded from the hand motor (M1) and premotor cortical (PM) areas, and internal Globus Pallidus (GPi) in 26 PD patients undergoing DBS implantation surgery. Participants executed rapid alternating hand movements in 30-second blocks, both with and without therapeutic pallidal stimulation. Behaviorally, the analysis revealed bradykinesia, with hand movement cycle width increasing linearly over time during DBS-OFF blocks. Crucially, there was a moment-to-moment correlation between M1 low beta burst duration and movement cycle width, a relationship that dissipated with therapeutic DBS. Further analyses suggest that high gamma activity correlates with enhanced motor performance with DBS-ON. Regardless of the nature of coupling, DBS’s modulation of cortical bursting activity appeared to amplify the brain signals’ informational content regarding instantaneous movement changes. Our findings underscore that DBS significantly reshapes the interaction between motor behavior and neural signals in PD, not only modulating specific bands but also expanding the system's capability to process and relay information for motor control. These insights shed light on the possible network mechanisms underlying DBS therapeutic effects, suggesting a profound impact on both neural and motor domains.