Multifunctional ytterbium oxide buffer for perovskite solar cells.

Perovskite solar cells (PSCs) comprise a solid perovskite absorber sandwiched between several layers of different charge-selective materials, ensuring unidirectional current flow and high voltage output of the devices1,2. A 'buffer material' between the electron-selective layer and the metal electrode in p-type/intrinsic/n-type (p-i-n) PSCs (also known as inverted PSCs) enables electrons to flow from the electron-selective layer to the electrode3-5. Furthermore, it acts as a barrier inhibiting the inter-diffusion of harmful species into or degradation products out of the perovskite absorber6-8. Thus far, evaporable organic molecules9,10 and atomic-layer-deposited metal oxides11,12 have been successful, but each has specific imperfections. Here we report a chemically stable and multifunctional buffer material, ytterbium oxide (YbOx), for p-i-n PSCs by scalable thermal evaporation deposition. We used this YbOx buffer in the p-i-n PSCs with a narrow-bandgap perovskite absorber, yielding a certified power conversion efficiency of more than 25%. We also demonstrate the broad applicability of YbOx in enabling highly efficient PSCs from various types of perovskite absorber layer, delivering state-of-the-art efficiencies of 20.1% for the wide-bandgap perovskite absorber and 22.1% for the mid-bandgap perovskite absorber, respectively. Moreover, when subjected to ISOS-L-3 accelerated ageing, encapsulated devices with YbOx exhibit markedly enhanced device stability.

Suppressed phase segregation for triple-junction perovskite solar cells.

The tunable bandgaps and facile fabrication of perovskites make them attractive for multi-junction photovoltaics1,2. However, light-induced phase segregation limits their efficiency and stability3-5: this occurs in wide-bandgap (>1.65 electron volts) iodide/bromide mixed perovskite absorbers, and becomes even more acute in the top cells of triple-junction solar photovoltaics that require a fully 2.0-electron-volt bandgap absorber2,6. Here we report that lattice distortion in iodide/bromide mixed perovskites is correlated with the suppression of phase segregation, generating an increased ion-migration energy barrier arising from the decreased average interatomic distance between the A-site cation and iodide. Using an approximately 2.0-electron-volt rubidium/caesium mixed-cation inorganic perovskite with large lattice distortion in the top subcell, we fabricated all-perovskite triple-junction solar cells and achieved an efficiency of 24.3 per cent (23.3 per cent certified quasi-steady-state efficiency) with an open-circuit voltage of 3.21 volts. This is, to our knowledge, the first reported certified efficiency for perovskite-based triple-junction solar cells. The triple-junction devices retain 80 per cent of their initial efficiency following 420 hours of operation at the maximum power point.

Non-concordant epigenetic and transcriptional responses to acute thermal stress in western mosquitofish (Gambusia affinis).

Climate change is intensifying the frequency and severity of extreme temperatures. Understanding the molecular mechanisms underlying the ability to cope with acute thermal stress is key for predicting species' responses to extreme temperature events. While many studies have focused on the individual roles of gene expression, post-transcriptional processes and epigenetic modifications in response to acute thermal stress, the relative contribution of these molecular mechanisms remains unclear. The wide range of thermal limits of western mosquitofish (Gambusia affinis) provides an opportunity to explore this interplay. Here, we quantified changes in gene expression, alternative splicing, DNA methylation and microRNA (miRNA) expression in muscle tissue dissected from mosquitofish immediately after reaching high (CTmax) or low thermal limit (CTmin). Although the numbers of genes showing expression and splicing changes in response to acute temperature stress were small, we found a possibly larger and non-redundant role of splicing compared to gene expression, with more genes being differentially spliced (DSGs) than differentially expressed (DEGs), and little overlap between DSGs and DEGs. We also identified a small proportion of CpGs showing significant methylation change (i.e. differentially methylated cytosines, DMCs) in fish at thermal limits; however, there was no overlap between DEGs and genes annotated with DMCs in both CTmax and CTmin experiments. The weak interplay between epigenetic modifications and gene expression was further supported by our discoveries of no differentially expressed miRNAs. These findings provide novel insights into the relative role of different molecular mechanisms underlying immediate responses to extreme temperatures and demonstrate non-concordant responses of epigenetic and transcriptional mechanisms to acute temperature stress.

Generation for high-dimensional caustics and artificially tailored structured caustic beams.

We theoretically propose and demonstrate topological parabolic umbilic beams (PUBs) with high-dimensional caustic by mapping catastrophe theory into optics. The PUBs are first experimentally observed via dimensionality reduction. Due to the high-dimensionality, such light beams exhibit rich caustic structures characterized by optical singularities where the high-intensity gradient appears. Further, we propose an improved caustic approach to artificially tailored structured beams which exhibit significant intensity gradient and phase gradient. The properties can trap and drive particles to move along the predesigned trajectory, respectively. The advantages for structured caustic beams likely enable new applications in flexible particle manipulation, light-sheet microscopy, and micromachining.

The role of plastic and evolved DNA methylation in parallel adaptation of threespine stickleback (Gasterosteus aculeatus).

Repeated phenotypic patterns among populations undergoing parallel evolution in similar environments provide support for the deterministic role of natural selection. Epigenetic modifications can mediate plastic and evolved phenotypic responses to environmental change and might make important contributions to parallel adaptation. While many studies have explored the genetic basis of repeated phenotypic divergence, the role of epigenetic processes during parallel adaptation remains unclear. The parallel evolution of freshwater ecotypes of threespine stickleback fish (Gasterosteus aculeatus) following colonization of thousands of lakes and streams from the ocean is a classic example of parallel phenotypic and genotypic adaptation. To investigate epigenetic modifications during parallel adaptation of threespine stickleback, we reanalysed three independent data sets that investigated DNA methylation variation between marine and freshwater ecotypes. Although we found widespread methylation differentiation between ecotypes, there was no significant tendency for CpG sites associated with repeated methylation differentiation across studies to be parallel versus nonparallel. To next investigate the role of plastic versus evolved changes in methylation during freshwater adaptation, we explored if CpG sites exhibiting methylation plasticity during salinity change were more likely to also show evolutionary divergence in methylation between ecotypes. The directions of divergence between ecotypes were generally in the opposite direction to those observed for plasticity when ecotypes were challenged with non-native salinity conditions, suggesting that most plastic responses are likely to be maladaptive during colonization of new environments. Finally, we found a greater number of CpG sites showing evolved changes when ancestral marine ecotypes are acclimated to freshwater environments, whereas plastic changes predominate when derived freshwater ecotypes transition back to their ancestral marine environments. These findings provide evidence for an epigenetic contribution to parallel adaptation and demonstrate the contrasting roles of plastic and evolved methylation differences during adaptation to new environments.

Generation of high-dimensional caustic beams via phase holograms using angular spectral representation.

Using angular spectral representation, we demonstrate a generalized approach for generating high-dimensional elliptic umbilic and hyperbolic umbilic caustics by phase holograms. The wavefronts of such umbilic beams are investigated via the diffraction catastrophe theory determined by the potential function, which depends on the state and control parameters. We find that the hyperbolic umbilic beams degenerate into classical Airy beams when the two control parameters are simultaneously equal to zero, and elliptic umbilic beams possess an intriguing autofocusing property. Numerical results demonstrate that such beams exhibit clear umbilics in 3D caustic, which link the two separated parts. The dynamical evolutions verify that they both possess prominent self-healing properties. Moreover, we demonstrate that hyperbolic umbilic beams follow along a curve trajectory during propagation. As the numerical calculation of diffraction integral is relatively complex, we have developed an effective approach for successfully generating such beams by using phase hologram represented by angular spectrum. Our experimental results are in good agreement with the simulations. Such beams with intriguing properties are likely to be applied in emerging fields such as particle manipulation and optical micromachining.

Customizing non-diffracting structured beams.

We demonstrate a universal approach to designing and generating non-diffracting structured light beams with arbitrary shapes. Such light beams can be tailored by predefining suitable spectral phases that match the corresponding beam shapes in the transverse plane. We develop a practical spectral superposition algorithm to discuss the non-diffracting properties and experimentally confirm our numerical results. Our proposed approach differs from that of classical non-diffracting beams, which are always constructed from wave equation solutions. The various non-diffracting structured beams could help manipulate particles following arbitrary transverse shapes and are likely to give rise to new applications in optical micromachining.

The Selective NLRP3-inflammasome inhibitor MCC950 Mitigates Post-resuscitation Myocardial Dysfunction and Improves Survival in a Rat Model of Cardiac Arrest and Resuscitation.

PURPOSE: To investigate the effects of the selective NLRP3 inflammasome inhibitor MCC950 on post-resuscitation myocardial function and survival in a rat model of cardiopulmonary resuscitation (CPR). METHODS: Thirty-six Sprague Dawley rats were randomized into three groups: (1) MCC950, (2) control, and (3) sham. Each group consisted of a 6 h non-survival subgroup (n = 6) and a 48 h survival subgroup (n = 6). Ventricular fibrillation (VF) was induced and untreated for 6 min. CPR was initiated and continued for 8 min. Resuscitation was attempted with a 4 J defibrillation. MCC950 (10 mg/kg) or vehicle was administered via intraperitoneal injection immediately after the return of spontaneous circulation (ROSC). Myocardial function and sublingual microcirculation were measured after ROSC in the non-survival subgroups. Plasma levels of interleukin Iß (IL-1ß) and cardiac troponin I (cTnI) were measured at baseline and 6 h in the non-survival subgroups. Heart tissue was harvested to measure the NLRP3 inflammasome constituents, including NLRP3, apoptosis-associated speck-like protein (ASC), Caspase-1, and IL-1ß. Survival duration and neurologic deficit score (NDS) were recorded and evaluated among survival groups. RESULTS: Post-resuscitation myocardial function and sublingual microcirculation were improved in MCC950 compared with control (p < 0.05). IL-1ß and cTnI were decreased in MCC950 compared to control (p < 0.01). The MCC950 treated groups showed significantly reduced ASC, caspase-1, and IL-1ß compared with the control group (p < 0.05). Survival at 48 h after ROSC was greater in MCC950 (p < 0.05) with improved NDS (p < 0.05). CONCLUSION: Administration of MCC950 following ROSC mitigates post-resuscitation myocardial dysfunction and improves survival.

Functional interplay of histone lysine 2-hydroxyisobutyrylation and acetylation in Arabidopsis under dark-induced starvation.

Lysine 2-hydroxyisobutyrylation (Khib) is a novel type of histone acylation whose prevalence and function in plants remain unclear. Here, we identified 41 Khib sites on histones in Arabidopsis thaliana, which did not overlap with frequently modified N-tail lysines (e.g. H3K4, H3K9 and H4K8). Chromatin immunoprecipitation-sequencing (ChIP-seq) assays revealed histone Khib in 35% of protein-coding genes. Most Khib peaks were located in genic regions, and they were highly enriched at the transcription start sites. Histone Khib is highly correlated with acetylation (ac), particularly H3K23ac, which it largely resembles in its genomic and genic distribution. Notably, co-enrichment of histone Khib and H3K23ac correlates with high gene expression levels. Metabolic profiling, transcriptome analyses, and ChIP-qPCR revealed that histone Khib and H3K23ac are co-enriched on genes involved in starch and sucrose metabolism, pentose and glucuronate interconversions, and phenylpropanoid biosynthesis, and help fine-tune plant response to dark-induced starvation. These findings suggest that Khib and H3K23ac may act in concert to promote high levels of gene transcription and regulate cellular metabolism to facilitate plant adaption to stress. Finally, HDA6 and HDA9 are involved in removing histone Khib. Our findings reveal Khib as a conserved yet unique plant histone mark acting with lysine acetylation in transcription-associated epigenomic processes.

Prognostic analysis of posterior fossa decompression with or without cerebellar tonsillectomy for Chiari malformation type I: a multicenter retrospective study.

OBJECTIVE: The purpose of this study was to compare the prognosis of patients with Chiari malformation type I (CM-I) treated with posterior fossa decompression with duraplasty (PFDD) and posterior fossa decompression with resection of tonsils (PFDRT). METHODS: The clinical data of patients with CM-I treated using these two procedures in three medical centers between January 2016 and June 2021 were retrospectively analyzed and divided into PFDD and PFDRT groups according to the procedures. The Chicago Chiari Outcome Scale (CCOS) was used to score the patients and compare the prognosis of the two groups. RESULTS: A total of 125 patients with CM-I were included, of whom 90 (72.0%) were in the PFDD group, and 35 (28.0%) were in the PFDRT group. There was no significant difference in the overall essential characteristics of the two groups. Moreover, there was no significant difference in complication rates (3.3% vs 8.6%, p = 0.348), CCOS scores (13.5 ± 1.59 vs 14.0 ± 1.21, p = 0.111), and the probability of poor prognosis (25.6% vs 11.4%, p = 0.096) between the two groups. Nevertheless, a subgroup of patients who had CM-I combined with syringomyelia (SM) revealed higher CCOS scores (13.91 ± 1.12 vs 12.70 ± 1.64, p = 0.002) and a lower probability of poor prognosis (13.0% vs 40.4%, p = 0.028) in the PFDRT than in the PFDD group. Also, SM relief was more significant in patients in the PFDRT compared to the PFDD group. A logistic multifactor regression analysis of poor prognosis in patients with CM-I and SM showed that the PFDRT surgical approach was a protective factor compared to PFDD. Furthermore, by CCOS analysis, it was found that the main advantage of PFDRT in treating patients with CM-I and SM was to improve patients' nonpain and functionality scores. CONCLUSIONS: Compared with PFDD, PFDRT is associated with a better prognosis for patients with CM-I and SM and is a protective factor for poor prognosis. Therefore, the authors suggest that PFDRT may be considered for patients with CM-I and SM.

Complementary genomic and epigenomic adaptation to environmental heterogeneity.

While adaptation is commonly thought to result from selection on DNA sequence-based variation, recent studies have highlighted an analogous epigenetic component as well. However, the relative roles of these mechanisms in facilitating population persistence under environmental heterogeneity remain unclear. To address the underlying genetic and epigenetic mechanisms and their relationship during environmental adaptation, we screened the genomes and epigenomes of nine global populations of a predominately sessile marine invasive tunicate, Botryllus schlosseri. We detected clear population differentiation at the genetic and epigenetic levels. Patterns of genetic and epigenetic structure were significantly influenced by local environmental variables. Among these variables, minimum annual sea surface temperature was identified as the top explanatory variable for both genetic and epigenetic variation. However, patterns of population structure driven by genetic and epigenetic variation were somewhat distinct, suggesting possible autonomy of epigenetic variation. We found both shared and specific genes and biological pathways among genetic and epigenetic loci associated with environmental factors, consistent with complementary and independent contributions of genetic and epigenetic variation to environmental adaptation in this system. Collectively, these mechanisms may facilitate population persistence under environmental change and sustain successful invasions across novel environments.

In situ siloxane passivation of colloidal lead halide perovskite via hot injection for light-emitting diodes.

All-inorganic cesium lead halide perovskite (CsPbX3; X = Cl, Br) nanocrystals (NCs) are synthesized via a modified hot injection method using 3-mercaptopropyltrimethoxysilane (MPTMS), together with oleic acid and oleylamine, for in situ passivation of the surface defects. The surface chemistry, revealed by Fourier transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS) techniques, shows an absence of Si-O-Si network and C-O groups on these in situ passivated CsPbX3 NCs, denoted as InMP-CsPbX3, which is in strong contrast to the counterpart NCs obtained via a postsynthesis exchange strategy. The x-ray diffraction (XRD) pattern indicates a lattice structure significantly strained from the cubic structure. The synthesis of these InMP-CsPbX3 NCs is highly reproducible, and the colloids are stable in nonpolar solvents. The emission wavelength of CsPb(Cl/Br)3 mixed halide perovskite NCs is tuned from 405 nm to 508 nm by reducing the nominal Cl/Br ratio, while the photoluminescence quantum yield (PLQY) is greatly enhanced over the whole spectral range. More importantly, the InMP-treatment is among the few strategies that are promising for electroluminescence in light-emitting diodes.

The Epigenetic Signature of Colonizing New Environments in Anolis Lizards.

Founder populations often show rapid divergence from source populations after colonizing new environments. Epigenetic modifications can mediate phenotypic responses to environmental change and may be an important mechanism promoting rapid differentiation in founder populations. Whereas many long-term studies have explored the extent to which divergence between source and founder populations is genetically heritable versus plastic, the role of epigenetic processes during colonization remains unclear. To investigate epigenetic modifications in founding populations, we experimentally colonized eight small Caribbean islands with brown anole lizards (Anolis sagrei) from a common source population. We then quantitatively measured genome-wide DNA methylation in liver tissue using reduced representation bisulfite sequencing of individuals transplanted onto islands with high- versus low-habitat quality. We found that lizard sex and habitat quality explained a significant proportion of epigenetic variation. Differentially methylated cytosines mapped to genes that encode proteins with functions likely to be relevant to habitat change (e.g., signal transduction, immune response, circadian rhythm). This study provides experimental evidence of a relationship between epigenetic responses and the earliest stages of colonization of novel environments in nature and suggests that habitat quality influences the nature of these epigenetic modifications.

Regulation of indoleamine 2, 3-dioxygenase in hippocampal microglia by NLRP3 inflammasome in lipopolysaccharide-induced depressive-like behaviors.

In the brain, NLRP3 (Nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin-domain-containing 3) inflammasome is mainly expressed in microglia located in the hippocampus and other mood-regulated regions, which are particularly susceptible to stress. The activation of NLRP3 inflammasome and production of the activation products may contribute to the development of depressive disorder and memory deficits. Indoleamine 2, 3-dioxygenase (IDO) is a key factor mediating inflammation and major depressive disorder (MDD). We here generated NLRP3 and apoptosis-associated speck-like protein containing caspase recruitment domain (ASC)-knockout mice, respectively, to verify the effects of NLRP3 or ASC deficiency on lipopolysaccharide (LPS)-induced depressive-like behaviors, neuroinflammation, and regulation of IDO expression. Furthermore, we treated these mice with the antidepressant clomipramine (CLO) to observe its effect on depressive-like behaviors and the expression of the NLRP3 inflammasome and LPS-induced IDO. We found that intraperitoneal LPS administration led to marked depressive-like behavior and neuroinflammation. NLRP3 or ASC deficiency attenuated LPS-induced depressive-like symptoms and increased IDO gene expression, which was accompanied by inhibition of LPS-induced microglial activation, suggesting that IDO may be a downstream mediator of the NLRP3 inflammasome in inflammation-mediated depressive-like behaviors. Clomipramine administration ameliorated depressive-like behavior in LPS-treated mice by regulating the expression of ASC and IDO. In conclusion, NLRP3 inflammasome is involved in LPS-induced depressive-like behaviors, and that NLRP3 and ASC may play roles in regulating IDO expression in microglia. This may be a potential mechanism for its involvement in MDD. The antidepressant effect of clomipramine may be exerted through the regulation of ASC-mediated expression of IDO.

Effects of graded levels of starch on the non-specific immune responses, antioxidant capacities and intestinal health in Chinese mitten crab, Eriocheir inensis.

A 9-week feeding trial was conducted to investigate the effects of graded levels of dietary starch (12%, 17%, 22%, 27% and 32%) on growth, non-specific immune responses, antioxidant capacities, immunity genes expression levels and pathogen resistance in Chinese mitten crab, Eriocheir inensis (initial body weight: 10.5 ± 0.5 g). Results showed that the highest weight gain rate of crabs was obtained in group containing 22% dietary starch. The highest activity of acid phosphatase, phenoloxidase and lysozyme in blood was found in crabs fed with 22-27% dietary starch. Additionally, 17%-27% dietary starch significantly increased the activities of superoxide dismutase and glutathione peroxidase, reduced malondinaldehyde content and then increased the total antioxidant capacities in hepatopancreas of crabs. The highest activity of alanine aminotransferase and aspartate aminotransferase was found in crabs fed with 32% dietary starch, indicating that excess starch had a negative effect on the liver function of crabs. With the dietary starch level increased, the transcription factors gene expression of the pro-inflammatory factors were significantly up-regulated, and the highest ILF2, IL-16, Relish and ADAM10 was found in crabs fed with dietary 32% starch, which may potentially promote the inflammatory response in intestines. Moreover, with the dietary starch increased, the activity of phenoloxidase and lysozyme, as well as the gene expression of crustin, were all increased in crabs after challenge against Citrobacter freundii, which demonstrated that additional dietary starch could provide immune-protection and help crabs improve their resistance against pathogens. In conclusion, these results suggest that adequate dietary starch can increase growth, enhance innate immune responses and promote disease resistance, reduce oxidative stress and inflammatory response in E. inensis. Taken together, 22-27% dietary starch (25.9-30.8% dietary carbohydrate) was suggested as a digestible energy source in crabs feed.

Effects of dietary Pediococcus acidilactici GY2 single or combined with Saccharomyces cerevisiae or/and ß-glucan on the growth, innate immunity response and disease resistance of Macrobrachium rosenbergii.

One Pediococcus acidilactici strain, named PA-GY2 was isolated from the gut of cultured Macrobrachium rosenbergii. In order to better examine the potential scope and applicability of this strain in M. rosenbergii culture, based on the control diet, four experimental diets containing single or combined immunostimulants were produced by supplementing with yeast (Saccharomyces cerevisiae, SC) or/and ß-glucan (G), then fed to the prawns (6.70 g ± 0.74) in five groups, which were named as group C (control group), P (PA-GY2), PS (PA-GY2 + SC, 1:1), PG (PA-GY2 + G) and PGS (PA-GY2 + SC + G), respectively. After a 60-day feeding trial, growth performance, feed utilization, immune response and disease resistance of prawns were evaluated in the present study. Results indicated that (1) The growth performance of the prawns in group PS and PGS were significantly improved. The prawns in group PGS presented the lowest feed coefficiency (FC), while prawns in group C presented the highest FC. (2) The protease activity was significantly improved by dietary immunostimulants supplementation, meanwhile, prawns in the group PS presented the highest lipase activity. (3) The highest total hemocyte count and respiratory burst activity were found in the group P and PG, respectively. The phagocytic index of the prawns in the group C was significantly lower than those in group P and PGS. (4) Dietary PA-GY2 single or combined with SC or/and ß-glucan increased the immune related genes expression, including some antibacterial and antioxidant enzymes, while decreased the tumor necrosis factor-α gene expression, which led to the decreased cumulative mortality rate of prawns during the Aeromonas hydrophila challenge test. Based on the results of growth performance, digestive enzymes activity and immune response of M. rosenbergii, PA-GY2 supplementation, single or combined with SC or/and ß-glucan could be suggested as promising immunostimulants in prawns farming.

An Efficient Resource Allocation Strategy for Edge-Computing Based Environmental Monitoring System.

The cloud computing and microsensor technology has greatly changed environmental monitoring, but it is difficult for cloud-computing based monitoring system to meet the computation demand of smaller monitoring granularity and increasing monitoring applications. As a novel computing paradigm, edge computing deals with this problem by deploying resource on edge network. However, the particularity of environmental monitoring applications is ignored by most previous studies. In this paper, we proposed a resource allocation algorithm and a task scheduling strategy to reduce the average completion latency of environmental monitoring application, when considering the characteristic of environmental monitoring system and dependency among task. Simulations are conducted, and the results show that compared with the traditional algorithms. With considering the emergency task, the proposed methods decrease the average completion latency by 21.6% in the best scenario.

Genome-wide DNA methylation signatures of infection status in Trinidadian guppies (Poecilia reticulata).

Epigenetic modification, especially DNA methylation, can play an important role in mediating gene regulatory response to environmental stressors and may be a key process affecting phenotypic plasticity and adaptation. Parasites are potent stressors with profound physiological and ecological effects on their hosts, yet it remains unclear how parasites influence host methylation patterns. Here, we used a well-studied host-parasite system, the guppy Poecilia reticulata and its ectoparasitic monogenean Gyrodactylus turnbulli to gain mechanistic insight into the dynamics of DNA methylation in host-parasite interactions. To explore this, we quantitatively measured genome-wide DNA methylation in guppy skin tissue using reduced representation bisulphite sequencing and characterized differential methylation patterns in guppies during distinct phases of infection. We identified 365, 313, and 741 differentially methylated regions (DMRs) between infected and control fish in early infection, peak infection and recovery phases, respectively. The magnitude of the methylation difference was moderate in DMRs, with an average of 29% (early infection), 27% (peak infection) and 30% (recovery) differential methylation per DMR. Approximately 50% of DMRs overlapped with CpG islands, and over half of the DMRs overlapped with gene bodies, several of which encode proteins relevant to immune response. These findings provide the first evidence of an epigenetic signature of infection by ectoparasites and demonstrate the changing relationship between epigenetic variation and immune response in distinct phases of infection.

Hypothermia alleviated LPS-induced acute lung injury in Rat models through TLR2/MyD88 pathway.

Acute lung injury (ALI) is a common clinical syndrome in ICU departments with high mortality. The pathology of ALI is still not clear and there is no specific and efficient treatment against ALI. In this study, we established ALI rat model through lipopolysaccharide administration. We found that hypothermia therapy led to significant improvement in oxygenation index, edema formation and pathological score, demonstrating that hypothermia is beneficial to the recovery of lung function and alleviation of lung injury. Besides, hypothermia resulted in a decrease in plasminogen activator inhibitor-1(PAI-1) concentration, showing the inflammation was partially inhibited. This was also confirmed by a decrease in TNF-α mRNA and protein level in hypothermia group. The effect of hypothermia was mediated by TLR2/MyD88 signaling, which led to the alteration in NF-κB p65 level. Collectively, this study indicated that hypothermia therapy was potentially an efficient therapy against ALI.

Anti-inflammatory effect of dexmedetomidine combined with hypothermia on acute respiratory distress syndrome in rats.

BACKGROUND: To investigate the protective effect of combination of dexmedetomidine and hypothermia on lipopolysaccharide (LPS) induced acute respiratory distress syndrome in rats. METHODS: Fifty male Wistar rats were randomly divided into five groups, with 10 rats in each group. The acute respiratory distress syndrome model was reproduced by LPS injected into the right external jugular vein (L group); only saline was injected into the right external jugular vein for control group (C group). In hypothermia group (T group), the body temperature was lowered to 32.5°C-33.0°C after 1 h of LPS injection, and 10 rats were sacrificed at 8 h. Group dexmedetomidine (D group) and dexmedetomidine combined with hypothermia group (DT group) received intraperitoneal dexmedetomidine 30 min before LPS was injected. The arterial blood gas was determined in all the groups before and 8 h after instillation of saline or LPS, and the oxygenation index (PaO2/FiO2) was calculated. The pro-inflammatory cytokines TNF-alpha (TNF-α) and interleukin- 6 (IL-6) levels were determined by enzyme-linked immunosorbent assay. The expression of inflammatory signaling proteins in bronchial alveolar lavage fluid was determined by Western blot. RESULTS: Compared with group L, TNF-α and IL-6 levels in serum of rats were significantly lower (P < 0.05), the expression of toll-like receptors 4 and phosphorylated c-Jun N-terminal kinase was significantly lower (P < 0.05), and the p-Akt level was significantly higher (P < 0.05). Moreover, the dexmedetomidine combined with hypothermia treated was superior to the single method. CONCLUSIONS: The combination of dexmedetomidine and hypothermia could alleviate acute lung injury in rats.