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Over the last half-century, direct measurements of surface forces have been instrumental in the exploration of a multitude of phenomena in liquid, soft, and biological matter. Measurements of van der Waals interactions, electrostatic interactions, hydrophobic interactions, structural forces, depletion forces, and many other effects have checked and challenged theoretical predictions and motivated new models and understanding. The gold-standard instrument for these measurements is thesurface force balance(SFB), orsurface forces apparatus, where interferometry is used to detect the interaction force and distance between two atomically smooth planes, with 0.1 nm resolution, over separations from about 1 µm down to contact. The measured interaction forcevs.distance gives access to the free energy of interaction across the fluid film; a fundamental quantity whose general form and subtle features reveal the underlying molecular and surface interactions and their variation. Motivated by new challenges in emerging fields of research, such as energy storage, biomaterials, non-equilibrium and driven systems, innovations to the apparatus are now clearing the way for new discoveries. It is now possible to measure interaction forces (and free energies) with control of electric field, surface potential, surface chemistry; to measure time-dependent effects; and to determine structurein situ. Here, we provide an overview the operating principles and capabilities of the SFB with particular focus on the recent developments and future possibilities of this remarkable technique.
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Traumatic brain injury (TBI) frequently results in cardiac dysfunction and impacts the quality of survivors' life. It has been reported that carbon monoxide-releasing molecule-3 (CORM-3) administration immediately after hemorrhagic shock and resuscitation (HSR) ameliorated the HSRinduced cardiac dysfunctions. The purpose of this study was to determine whether the application of CORM-3 on TBI exerted therapeutic effects against TBI-induced cardiac dysfunctions. Rats were randomly divided into four groups (n = 12) including Sham, TBI, TBI/CORM-3 and TBI/inactive CORM-3 (iCORM-3) groups. TBI was established by a weight-drop model. The rats in the TBI/CORM-3 group and TBI/iCORM-3 group were intravenously injected with CORM-3 and iCORM-3 (4 mg/kg) following TBI, respectively. The time of death in the rats that did not survive within 24 h was recorded. 24 h post-trauma, the cardiac function, pathological change, serum troponin T and creatine kinase-MB (CK-MB) levels, pyroptosis, apoptosis and expressions of TUNEL staining, Gasdermin D (GSDMD), IL-1ß, IL-18, ratio Bax/Bcl-2 were assessed by echocardiography, hematoxylin-eosin staining, chemiluminescence, immunofluorescence, and western blot assays, respectively. TBI-treated rats exhibited dramatically decreased ejection fraction and aggravated myocardial injury, increased mortality rate, elevated levels of serum troponin T and CK-MB, promoted cardiac pyroptosis and apoptosis, and upregulated expressions of cleaved caspase-3, GSDMD N-terminal fragments, IL-1ß, IL-18, and ratio of Bax/Bcl-2, whereas CORM-3 partially reversed these changes. CORM-3 ameliorated TBI-induced cardiac injury and dysfunction. This mechanism may be responsible for the inhibition of pyroptosis and apoptosis in cardiomyocyte.
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Severe hemorrhage shock and resuscitation (HSR) has been reported to induce myocardial ischemia-reperfusion injury (MIRI), resulting in a poor prognosis. Hirudin, an effective thrombin inhibitor, can offer protection against MIRI. This study aimed to determine if hirudin administration ameliorates HSR-induced MIRI and the underlying mechanism. A rat model of HSR was established by bleeding rats to a mean arterial blood pressure of 30-35 mmHg for 45 min and then resuscitating them with all the shed blood through the left femoral vein. After HSR, 1 mg/kg of hirudin was administrated immediately. At 24 h after HSR, the cardiac injury was assessed using serum CK-MB, cTnT, hematoxylin-eosin (HE) staining, echocardiography, M1-polarized macrophages, and pyroptosis-associated factors, including cleaved caspase-1, Gasdermin D (GSDMD) N-terminal, IL-1ß, and IL-18 were measured by immunofluorescence and western blot assays. Nigericin, a unique agonist, was utilized to evaluate the responsibilities of NLRP3 signaling. Under the HSR condition, rats exhibited a significant increase in myocardial injury score, an elevation of serum cTnT, CK-MB levels, an aggrandization of M1-polarized macrophages, an upregulation of pyroptosis-associated factors, including cleaved caspase-1, GSDMD N-terminal, IL-1ß, and IL-18, but a significant decrease in left ventricular ejection fraction (EF%) and a reduction of left ventricular fractional shortening (FS%), while hirudin administration partially restored the changes. However, the NLRP3 agonist nigericin reversed the cardioprotective effects of hirudin. We determined the cardioprotective effects of hirudin against HSR-induced MIRI. The mechanism may involve the inhibition of NLRP3-induced pyroptosis.
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Traumatismo por Reperfusão Miocárdica , Choque Hemorrágico , Ratos , Animais , Traumatismo por Reperfusão Miocárdica/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Interleucina-18 , Hirudinas/farmacologia , Choque Hemorrágico/metabolismo , Volume Sistólico , Nigericina/farmacologia , Função Ventricular Esquerda , Caspase 1/metabolismo , Transdução de SinaisRESUMO
Long-term neurological deficits after severe traumatic brain injury (TBI), including cognitive dysfunction and emotional impairments, can significantly impair rehabilitation. Glial activation induced by inflammatory response is involved in the neurological deficits post-TBI. This study aimed to investigate the role of the stimulator of interferon genes (STING)-nucleotide-binding oligomerization domain-like receptor pyrin domain-containing-3 (NLRP3) signaling in a rodent model of severe TBI. Severe TBI models were established using weight-drop plus blood loss reinfusion model. Selective STING agonist ADU-S100 or antagonist C-176 was given as a single dose after modeling. Further, NLRP3 inhibitor MCC950 or activator nigericin, or caspase-1 inhibitor VX765, was given as an intracerebroventricular injection 30 min before modeling. After that, a novel object recognition test, open field test, force swimming test, western blot, and immunofluorescence assays were used to assess behavioral and pathological changes in severe TBI. Administration of C-176 alleviated TBI-induced cognitive dysfunction and emotional impairments, neuronal loss, and inflammatory activation of glia cells. However, the administration of STING agonist ADU-S100 exacerbated TBI-induced behavioral and pathological changes. In addition, STING activation exacerbated pyroptosis-associated neuroinflammation via promoting glial activation, as evidenced by increased cleaved caspase-1 and GSDMD N-terminal expression. In contrast, the administration of C-176 showed anti-pyroptotic effects. The neuroprotective effects of C-176 were partially reversed by the NLRP3 activator, nigericin. Collectively, glial STING is responsible for neuroinflammation post-TBI. However, pharmacologic inhibition of STING led to a remarkable improvement of neuroinflammation partly through suppressing NLRP3 signaling. The STING-NLRP3 signaling is a potential therapeutic target in TBI-induced neurological dysfunction.
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Lesões Encefálicas Traumáticas , Proteínas de Membrana , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Animais , Lesões Encefálicas Traumáticas/metabolismo , Inflamassomos/metabolismo , Inflamação/patologia , Proteínas de Membrana/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Nigericina/uso terapêuticoRESUMO
Using a surface force apparatus, a cholesteric liquid crystal was confined between two crossed cylindrical surfaces that induced strong planar anchoring and normal alignment of the chiral helix. The film thickness and total twist angle of the chiral molecular structure were simultaneously measured using multiple-beam optical interference. As the film thickness was increased and the chiral structure deformed, the twist angle remained almost unchanged until discontinuous changes occurred at critical distances that were equally spaced by one cholesteric half-pitch length. Structural deformations generated oscillatory elastic forces with periodically spaced maxima corresponding to twist transitions. These findings were reproduced using an equilibrium model of cholesteric confinement and force generation. The analysis indicates that the strength of the azimuthal surface anchoring on mica is high, exceeding 0.2 mJ m-2.
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Cristais Líquidos/química , Desenho de Equipamento , Fenômenos MecânicosRESUMO
Disease transmission across built environments has been found to be a serious health risk. Airborne transmission is a vital route of disease infection caused by bacteria and virus. However, tracing methods of airborne bacteria in both lab and field research failed to veritably express the transporting process of microorganism in the air. A new tracing method of airborne bacteria used for airborne transmission was put forward and demonstrated its feasibility by conducting a field evaluation on the basis of genetic modification and bioaerosol technology. A specific gene fragment (pFPV-mCherry fluorescent protein plasmid) was introduced into nonpathogenic E. coli DH5α as tracer bacteria by high-voltage electroporation. Gel electrophoresis and DNA sequencing proved the success of the synthesis. Genetic stability, effect of aerosolization on the survival rate of tracer bacteria, and the application of the tracer bacteria to the airborne bacteria transmission were examined in both lab and field. Both the introduced plasmid stability rates of tracer E. coli in pre-aerosolization and post-aerosolization were above 95% in five test days. Survival rate of tracer E. coli at 97.5%⯱â¯1.2% through aerosolization was obtained by an air-atomizer operated at an air pressure of 30 Psi. In the field experiment, the airborne transmission of E. coli between poultry houses was proved and emitted E. coli was more easily transmitted into self-house than adjacent house due to the ventilation design and weather condition. Our results suggested that the tracing method of airborne bacteria was available for the investigation of airborne microbial transmission across built environments.
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A weak alkaline condition (pH > 8) is a general requirement for oxidative self-polymerization of dopamine. Here, we first demonstrated the generation of polydopamine in an acidic environment via a hydrothermal method. The pH scope of self-polymerization of dopamine is extended to pH â¼ 1 in a hydrothermal process. Polydopamine generated via a hydrothermal method shows similar chemical features and radical scavenging activity with that generated in a basic environment.
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Dopamina/química , Concentração de Íons de Hidrogênio , Oxirredução , PolimerizaçãoRESUMO
The effect of amygdalin joint hydroxysafflor yellow A (HSYA) on the endplate chondrocytes derived from intervertebral discs of rats induced by IL-1beta and the possible mechanism were studied and explored. Chondrocytes were obtained from endplate of one-month SD rat intervertebral discs and cultured primary endplate chondrocytes. After identification, they were divided into normal group, induced group, amygdalin group, HSYA group and combined group. CCK-8 kit was adopted to detect the proliferation of the endplate chondrocytes. FCM was measured to detect the apoptosis. Real-time PCR method was adopted to observe the mRNA expression of Aggrecan, Col 2 alpha1, Col 10 alpha1, MMP-13 and the inflammatory cytokines IL-1beta. The protein expression of Col II, Col X was tested through immunofluorescence. Compared with the normal group, the proliferation of the endplate chondrocytes decreased while the apoptosis increased (P < 0.05). With down regulation of the mRNA expressions of Aggrecan, Col 2 alpha1 and up regulation of the mRNA expressions of Col 10 alpha1, MMP-13, IL-1beta (P < 0.05), the protein expression of Col II decreased while the protein expression of Col X increased. Compared with the induced group, amygdalin group, HSYA group, the combined group could inhibit the apoptosis and promote the proliferation (P < 0.05). They could increase the mRNA expressions of Aggrecan and Col 2 alpha1 while decrease the mRNA expressions of Col 10 alpha1, MMP-13 and IL-1beta (P < 0.05). They could also enhance the protein expression of Col II while reduce the protein expression of Col X. The effect of the combined group was significantly better than that of amygdalin and HSYA. Amygdalin joint HSYA could inhibit the degeneration of the endplate chondrocytes derived from intervertebral discs of rats induced by IL-1beta and better than the single use of amygdalin or HSYA.
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Amigdalina/farmacologia , Chalcona/análogos & derivados , Condrócitos/efeitos dos fármacos , Disco Intervertebral/citologia , Quinonas/farmacologia , Animais , Apoptose , Células Cultivadas , Chalcona/farmacologia , Colágeno/metabolismo , Sinergismo Farmacológico , Interleucina-1beta , RatosRESUMO
The stick-slip phenomenon widely exists in contact mechanics, from the macroscale to the nanoscale. During cholesteric-nematic unwinding by external fields, there is controversy regarding the role of planar surface anchoring, which may induce discontinuous stick-slip behaviors despite the well-known continuous transitions observed in past experiments. Here we observe three regimes, namely, constrained, stick-slip, and sliding-slip, under mechanical winding with different anchoring conditions, and measure the corresponding forces by the surface force balance. These behaviors result from a balance of cholesteric elastic torque and surface torque, reminiscent of the slip morphology on frictional substrates [T. G. Sano et al., Phys. Rev. Lett. 118, 178001 (2017)10.1103/PhysRevLett.118.178001], and provide evidence of dynamics in static rotational friction.
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The temperature inside broiler houses is crucial to broiler health, welfare, and productivity. High stocking density in broiler houses can easily lead to nonuniform temperature conditions, which would cause broilers to suffer cold and heat stress. It is essential to assess the temperature distribution inside broiler houses and investigate the factors that affect temperature uniformity. Therefore, in this study, temperature, wind velocity, and differential pressure were monitored in the aisle, at the sidewall inlet, and outside the sidewalls of a commercial stacked-deck cage broiler house in Northeast China aiming to continuously monitor the temperature throughout the entire fattening period. Results show that the maximum temperature difference increased from 1.85 °C to 6.43 °C, while the daily fluctuation increased from 2.27 °C to 5.80 °C. The highest temperature was consistently recorded at the side of the exhaust fans (p < 0.001) in the longitudinal direction. In the lateral direction, the temperature difference varies periodically with solar radiation. The average temperature at the southern location (23.58 ± 1.97 °C), which faces the sun, was higher than that at the northern location (23.35 ± 1.38 °C), which is in the shade, during periods of solar radiation (p < 0.001) at the last testing period. However, without solar radiation, the northern location recorded a warmer temperature (23.19 ± 1.41 °C) compared to the southern location (22.30 ± 1.67 °C) (p < 0.001). The lateral temperature differences are strongly positively correlated with solar radiation and wind speed (p < 0.001). In conclusion, the inside temperature nonuniformity and fluctuation increased as the broiler age increased, which affected the production performance of broilers. Nonuniform solar radiation and wind speed can lead to differences in the inlet temperature and air volume between both sidewalls, thereby affecting the uniformity of the lateral temperature inside the house.
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Manipulation of light during incubation may have an effect on post-hatch chicks through the role of prenatal stage. The effects of providing different wavelengths of light (white, blue, and green lights, dark as control) during incubation on the growth performance, organ development, immune response, stress related hormones, digestive enzymes and behaviour of post-hatch chicks were investigated for 1-42 days. A total of 60 chicks per light treatment in three batches were used in this study. The results showed that the percentage of chicks accessing to feed and water resources appeared not to be affected by incubation light. Chicks hatched under white light were found to have a growth advantage (p < 0.05). The weight of organs (except thymus), IgA, IgY, IgM and heterophil to lymphocyte (H/L) ratio for post-hatch chicks were not affected by incubation light (p > 0.05). Thymus weight was reduced in chicks incubated under blue light compared to dark incubation (p < 0.05). The jejunum amylase and ileum lipase activities were significantly affected by the light treatments (p < 0.01). All light incubation chicks had stable plasma corticosterone levels and may have better ability to cope with environmental changes. Hence, white light photoperiod incubation may have potential to improve post-hatch chicks' growth performance and environmental adaptability.
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Low-pressure systems (LPSs) are among the most critical weather systems, producing excessive precipitation that causes air temperatures to drop and rise considerably. Acute temperature changes directly affect poultry feed intake (FI) and laying performance. To explore the effects of LPSs on hens, the parameters of air temperature, relative humidity, egg production, and feed utilization efficiency were evaluated during different LPSs in three houses. Results indicated that about 2.8 ± 0.7 d, 2.4 ± 0.5 d, and 2.4 ± 0.5 d before the LPS landfall in houses 1, 2, and 3, respectively, the indoor air temperature started to decrease, with the average decreases being 1.7 °C ± 0.4 °C, 2.4 °C ± 0.6 °C, and 1.8 °C ± 0.4 °C, respectively. Significant differences were observed between different LPSs for reducing indoor air temperature (p < 0.05) in the three houses. In house 1, the egg production rates (EPRs) were decreased by 6.6% and 1.1% when LPSs 1 and 2 landed. The average egg weight (AEW) and FI during the LPS landfall were significantly higher than those before the LPS landfall (p < 0.01). Under successive LPSs landfall in the three houses, the EPRs initially reduced by 3.9%, 4.0%, and 0.5%, respectively, but the second LPS event increased the EPRs by 1.8%, 5.3%, and 1.0%, respectively. Furthermore, the LPS landfall increased the feed conversion ratio (FCRe) in the three houses, all above 2.00. In conclusion, LPSs can reduce heat stress, lower the EPRs, and lead to higher FI, FCRe, and AEW.
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Slightly acidic electrolyzed water (SAEW) is well-known for its highly potent antibacterial properties and safe residue-free nature. In this study, a comprehensive evaluation was conducted on 2 disinfection methods for waterline cleaning in poultry houses: (1) continuously add SAEW into the waterline and (2) the conventional waterline disinfection method, which includes regular use of high-concentration chemical disinfectant for soaking the waterline and flushing with water. The evaluation focused on the effects of these methods on bacteria levels in laying hens' drinking water, the fecal normal rate of laying hens, egg quality, as well as the economic costs and water footprint associated with each method. The results show that the inhibition rate of the control group was 52.45% to 80.36%, which used 1500 mg/L sodium dichloroisocyanurate (DCCNa) for soaking and then flushing with water. The bacterial levels in the waterline returned to pre-treatment levels 26 h after cleaning. However, the experimental group with an available chlorine concentration (ACC) of 0.3 mg/L SAEW showed a higher inhibition rate (99.90%) than the control group (P < 0.05) and exhibited a sustained antimicrobial effect. Regarding eggshell thickness, eggshell strength, and Haugh units of the egg, there were no significant differences between the experimental and control groups. However, the experimental group had higher egg weight and darker yolk color (P < 0.05) than those of the control group. Besides, the experimental group exhibited a higher fecal normal rate and a lower water footprint than those of the control group. Hence, SAEW represents a favorable choice for disinfecting drinking water in poultry houses due to its ease of preparation, lack of residue, energy efficiency, and efficient antibacterial properties. To ensure adequate sanitation, it is recommended to incorporate SAEW with an ACC of 0.3 mg/L into the daily management of the drinking water system for laying hens.
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Desinfetantes , Água Potável , Animais , Feminino , Água/química , Galinhas , Óvulo , Desinfetantes/farmacologia , Cloro/farmacologia , Bactérias , Antibacterianos/farmacologiaRESUMO
Severe traumatic brain injury (TBI) can result in persistent complications, including circadian rhythm disorder, that substantially affect not only the injured people, but also the mood and social interactions with the family and the community. Pyroptosis in GFAP-positive astrocytes plays a vital role in inflammatory changes post-TBI. We determined whether VX-765, a low molecular weight caspase-1 inhibitor, has potential therapeutic value against astrocytic inflammation and pyroptosis in a rodent model of TBI plus hemorrhagic shock and resuscitation (HSR). A weight-drop plus bleeding and refusion model was used to establish traumatic exposure in rats. VX-765 (50 mg/kg) was injected via the femoral vein after resuscitation. Wheel-running activity was assessed, brain magnetic resonance images were evaluated, the expression of pyroptosis-associated molecules including cleaved caspase-1, gasdermin D (GSDMD), and interleukin-18 (IL-18) in astrocytes in the region of anterior hypothalamus, were explored 30 days post-trauma. VX-765-treated rats had significant improvement in circadian rhythm disorder, decreased mean diffusivity (MD) and mean kurtosis (MK), increased fractional anisotropy (FA), an elevated number and branches of astrocytes, and lower cleaved caspase-1, GSDMD, and IL-18 expression in astrocytes than TBI + HSR-treated rats. These results demonstrated that inhibition of pyroptosis-associated astrocytic activations in the anterior hypothalamus using VX-765 may ameliorate circadian rhythm disorder after trauma. In conclusion, we suggest that interventions targeting caspase-1-induced astrocytic pyroptosis by VX-765 are promising strategies to alleviate circadian rhythm disorder post-TBI.
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Lesões Encefálicas Traumáticas , Transtornos Cronobiológicos , Dipeptídeos , Choque Hemorrágico , para-Aminobenzoatos , Humanos , Ratos , Animais , Roedores , Choque Hemorrágico/tratamento farmacológico , Interleucina-18 , Lesões Encefálicas Traumáticas/tratamento farmacológico , CaspasesRESUMO
Spraying slightly acidic electrolyzed water (SAEW) has been considered as a potential approach to reduce airborne bacteria in laying-hen houses. In this study, the effects of spraying SAEW on airborne bacterial reduction were investigated in a laying-hen house as compared with using diluted didecyl dimethyl ammonium bromide (DDAB). Averaged air temperature reduced by approximate 1 degrees C and average relative humidity increased by 3% at a stable ventilation rate (about 2.5 m3 hr(-1) per bird) in the laying-hen house 30 min after spraying (120 mL m(-2)). Compared with the control without spraying, the airborne bacterial concentration was reduced by about 0.70 and 0.37 log10 colony-forming units (CFU) m(-3) in the 4 hr after spraying 120 mL m(-2) SAEW (available chlorine concentration [ACC] of 156 mg L(-1)) and diluted DDAB (active compound concentration of 167 mg L(-1)), respectively. Compared with spraying diluted DDAB, spraying SAEW was determined to be more effective for reducing airborne bacterial in laying-hen houses. The effects of spraying SAEW and diluted DDAB on airborne bacterial reduction in the laying-hen house increased with the increasing available chlorine concentrations for SAEW (156, 206, 262 mg L(-1)) and increasing active compound concentrations for diluted DDAB (167, 333, 500 mg L(-1)), respectively. Spraying SAEW and diluted DDAB with two levels of spraying volumes (120 and 90 mL m(-2)) both showed significant differences on airborne bacterial reduction in the laying-hen house (P < 0.05).
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Microbiologia do Ar/normas , Poluição do Ar em Ambientes Fechados/prevenção & controle , Galinhas , Peróxido de Hidrogênio/farmacologia , Animais , Bactérias/efeitos dos fármacos , Desinfetantes , Feminino , Umidade , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Oviposição , TemperaturaRESUMO
Hemorrhagic shock and resuscitation (HSR) can induce severe intestinal damages, thereby leading to sepsis and long-term complications including dysbacteriosis and pulmonary injury. The NOD-like receptor protein 3 (NLRP3) inflammasome facilitates inflammation-associated cell recruitment in the gastrointestinal tract, and participates in many inflammatory bowel diseases. Previous studies have shown that exogenous carbon monoxide (CO) exerts neuroprotective effects against pyroptosis after HSR. We aimed to investigate whether carbon monoxide-releasing molecules-3 (CORM-3), an exogenous CO compound, could attenuate HSR-induced intestinal injury and the potential underlying mechanism.Rats were subjected to a HSR model by bleeding and re-infusion. Following resuscitation, 4 mg/kg of CORM-3 was administered intravenously into femoral vein. At 24 h and 7 d after HSR modeling, the pathological changes in intestinal tissues were evaluated by H&E staining. The intestinal pyroptosis, glial fibrillary acidic protein (GFAP)-positive glial pyroptosis, DAO (diamine oxidase) content, intestine tight junction proteins including zonula occludens-1 (ZO-1) and claudin-1 were further detected by immunofluorescence, western blot and chemical assays at 7 d after HSR. CORM-3 administration led to significantly mitigated HSR-induced intestinal injury, aggravation of intestinal pyroptosis indicated by cleaved caspase-1, IL-1ß and IL-18, upregulation of GFAP-positive glial pyroptosis, decreased intensity of ZO-1 and claudin-1 in the jejunum, and increased of DAO in the serum. Nigericin, an agonist of NLRP3, significantly reversed the protective effects of CORM-3. CORM-3 alleviates the intestinal barrier dysfunction in a rodent model of HSR, and the potential mechanism may be associated with inhibition of NLRP3-associated pyroptosis. CORM-3 administration could be a promising therapeutic strategy for intestinal injury after hemorrhagic shock.
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Roedores , Choque Hemorrágico , Ratos , Animais , Roedores/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Monóxido de Carbono/metabolismo , Monóxido de Carbono/farmacologia , Choque Hemorrágico/complicações , Choque Hemorrágico/tratamento farmacológico , Choque Hemorrágico/metabolismo , Proteína Glial Fibrilar Ácida , Claudina-1 , Neuroglia/metabolismoRESUMO
BACKGROUND: Cognitive impairment, which includes perioperative psychological distress and cognitive dysfunction, can be determined by preoperative and post-operative neuropsychological tests. Several mechanisms have been proposed regarding the two-way communication between the immune system and the brain after surgery. We aimed to understand the mechanisms underlying perioperative neurocognitive disorders (PND) in elderly rats using an experimental abdominal surgery model. METHODS: 24-month-old SD rats were exposed to the abdominal surgery model (AEL) under 3% anesthesia. On day 15 and day 30 post-surgery, fractional anisotropy (FA) using diffusion kurtosis imaging (DKI) was measured. From day 25 to day 30 post-surgery, behavioral tests, including open field test (OFT), Morris water maze (MWM), novel object recognition (NOR), force swimming test (FST), and elevated plus maze (EPM), were performed. Then, the rats were euthanized to perform pathological analysis and western blot measurement. RESULTS: The rats exposed to AEL surgical treatment demonstrated significantly decreased time crossing the platform in the MWM, decreased recognition index in the NOR, reduced time in the open arm in the EPM, increased immobility time in the FST, and increased number of crossings in the OFT. Aged rats, after AEL exposure, further demonstrated decreased FA in the mPFC, nucleus accumbens (NAc), and hippocampus, together with reduced MAP2 intensity, attenuation of GAD65, VGlut2, CHAT, and phosphorylated P38MAPK expression, and increased reactive astrocytes and microglia. CONCLUSIONS: In this study, the aged rats exposed to abdominal surgery demonstrated both emotional changes and cognitive dysfunction, which may be associated with neuronal degeneration and reduced phosphorylated P38MAPK.
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Disfunção Cognitiva , Ratos , Animais , Sevoflurano , Ratos Sprague-Dawley , Disfunção Cognitiva/metabolismo , Emoções , Encéfalo/metabolismo , Hipocampo/metabolismo , Aprendizagem em Labirinto/fisiologiaRESUMO
Reducing airborne dust is an essential process for improving hen housing environment. Dust reduction effects of neutral electrolyzed water (pH 8.2) spray were investigated in a commercial tunnel-ventilated layer breeding house during production in northern China. A multipoint sampler was used to measure airborne dust concentration to study the dust reduction effects and distribution in the house. Compared with the control treatment (without spray), airborne dust level was reduced 34% in the 3 hr after spraying 216 mL m(-2) neutral electrolyzed water in the breeding house. The dust concentration was significantly higher during the periods of feed distribution (1.13 +/- 0.13 mg m(-3)) and artificial insemination (0.72 +/- 0.13 mg m(-3)) compared with after spray (0.47 +/- 0.09 mg m(-3)) and during lights-off period (0.29 +/- 0.08 mg m(-3)) in the three consecutive testing days (P <0.05). The experimental cage area was divided into four zones along the length of the house, with zone 1 nearest to the evaporative cooling pad and zone 4 nearest to the fans. The air temperature, relative humidity, airflow rate, and dust concentration were measured at the sampling points of the four zones in 3 consecutive days and mortality of the birds for the duration of a month were investigated. The results showed that the air temperature, airflow rate, dust concentration, and number of dead birds increase from zone 1 to zone 4 in the tunnel-ventilated layer breeding house.
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Poluição do Ar em Ambientes Fechados/prevenção & controle , Galinhas , Poeira/prevenção & controle , Abrigo para Animais/normas , Água/química , Bem-Estar do Animal , Animais , OviposiçãoRESUMO
Carbon dioxide (CO2) is always maintained at ambient levels by ventilation in commercial egg incubators. However, elevated CO2 levels during the early and late periods have been reported to improve the quality of chicks and shorten the hatch window. This study investigated the effect of precise CO2 supplementation during the early and late periods of incubation on embryo growth and incubation performance by developing and using a CO2 supplementation system to increase the CO2 level in an experimental egg incubator. The CO2 level was maintained at 1% in the early period (from the beginning to the 10th day of incubation, E0-E10) and in the late period (from internal pipping (IP) to the 21st day of incubation (E21), IP-E21) in an incubator for the treatment group, whereas the CO2 level was maintained at the ambient level in the other incubators for the control group. A comparative assessment of embryonic development, hatching characteristics, and hormone and nutrient levels was conducted for each trial. The experiment comprised three trials, with 300 Jing Hong No. 1 breeding eggs in each incubator. The elevated CO2 treatment significantly shortened the chick hatching time (H0) by 4â¯h (Pâ¯<â¯0.05) and the hatch window by 3â¯h (Pâ¯<â¯0.05) without affecting hatchability, chick weight at 1 d of age, brooding period, or quality score. At external pipping (EP), the heart weight, intestinal weight, relative intestinal weight, and relative heart weight in the treatment group were significantly higher than those in the control group (Pâ¯<â¯0.05). In addition, the embryonic intestine, relative intestine, and relative heart weights of the newly hatched chicks in the treatment group were significantly higher than those in the control group (Pâ¯<â¯0.05) at H0. The treatment significantly increased the concentration of corticosterone in the embryonic plasma during the period from IP to EP (Pâ¯<â¯0.05), promoted the secretion of triiodothyronine and tetraiodothyronine (Pâ¯<â¯0.05), and increased the glycogen content of the embryonic liver on E21 (Pâ¯<â¯0.05). This result indicates that elevated CO2 (1%) during the early and late periods of incubation accelerated embryonic organ development and shortened the chick hatching time and hatch window without affecting hatchability or hatchling quality, which can be explained by the synergistic functions of the secretion of plasma corticosterone and thyroid hormones and the accumulation of liver glycogen between the early and late periods of incubation.
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Dióxido de Carbono , Galinhas , Animais , Corticosterona , Óvulo , Tri-IodotironinaRESUMO
Conventional chemical disinfectants used for egg disinfection could result in toxic residue and endanger hatchability, chick quality, and pullet growth performance. Slightly acidic electrolyzed water (SAEW) is known as a novel disinfectant for egg sterilization due to its high efficiency and no residue. In this study, a comprehensive assessment of slightly acidic electrolyzed water and benzalkonium bromide solution (BBS) used in the disinfection channel was conducted to assess the microbial count, eggshell quality, and hatchability concomitantly. The results show that the sterilization efficiency of SAEW increased with an increase in available chlorine concentration (ACC), spraying volume, and sterilization duration. SAEW with an ACC of 150 mg/L and 10,000 mg/L benzalkonium bromide solution had the same sterilization rates of approximately 86.2% at a spraying volume of 0.5 mL/egg and sterilization duration of 180 s. Neither had significant effect on eggshell strength or thickness. The eggshell cuticle quality in the benzalkonium bromide group was significantly higher than the control group (no disinfection) and the 150 mg/L SAEW group. The embryo weight, relative embryo weight, hatchability, and embryonic mortality in the SAEW group had no significant differences of those in the benzalkonium bromide group. SAEW should be more popular because of its simple preparation, low cost, and no residue. Our results indicate SAEW is an alternative disinfectant for the sterilization of hatching eggs instead of conventional chemical disinfectants, such as benzalkonium bromide, and give a recommendation is using SAEW as a disinfectant with 150 mg/L ACC, 0.5 mL/egg spray volume, and disinfection for 180 s in the novel disinfection channel.