Differential expressions of hypothalamic thermosensitive TRP ion channels may underlie the posthatching ontogeny of brain cooling capacity in broiler chickens.

Two trials were performed to evaluate the association of hypothalamic abundances of thermosensitive transient receptor potential (TRP) ion channels with thermoregulation in broiler chickens. In trial 1, temporal changes in body temperatures, and hypothalamic expression patterns of TRP channels and thermoregulatory neurotransmitter concentrations were assessed from 3 to 42 d of age. In trial 2, the same variables were compared at 2 age stages between 2 distinct types of birds with high or low rectal temperatures (HRT or LRT). The core-to-brain temperature difference exhibited a rapid increase after hatching, arriving at a steady state in the fourth week (P < 0.01). The hypothalamus saw a progressive decrease of TRPV4 protein expression through 28 d (P < 0.01), followed by a great increase in the abundance of other channels right up to the end (P < 0.05). Compared to LRT birds, a decline in hypothalamic content of TRPV4 (P < 0.05), together with a bigger core-to-brain temperature difference (P < 0.01), was evident in the HRT counterpart at 33 d. In both trials, the core-to-brain and core-to-surface temperature differences were controlled in a synchronous and coordinated manner. These results allow concluding that developmental changes in the thermal sensitivity of hypothalamic neurons, determined by brain cooling capacity, involve a neuro-genomic mechanism, which regulates the ratio between thermosensitive TRP ion channels to attain a lower proportion of TRPV4 in comparison with other channels.

Reduced PGC-1ß protein expression may underlie corticosterone inhibition of mitochondrial biogenesis and oxidative phosphorylation in chicken muscles.

To uncover the molecular mechanism underlying glucocorticoid-induced loss of mitochondrial integrity in skeletal muscles, studies were performed to investigate whether the peroxisome proliferator-activated receptor γ coactivator 1 (PGC-1)-mediated pathway was involved in this process. In an in vivo trial, 3 groups of 30-d-old Arbor Acres male broilers were randomly subjected to one of the following treatments for 7 days: corticosterone (CORT, 30 mg/kg diet), control (blank), and pair-feeding (restricted to the same feed intake as for the CORT treatment), each with 6 replicates of 15 birds. Mitochondrial abundance, morphology, and function were determined in the pectoralis major and biceps femoris muscles. In an in vitro trial, a primary culture of embryonic chick myotubes was incubated with a serum-free medium for 24 h in the presence or absence of CORT (0, 200, and 1,000 nM). Results showed that CORT destroyed mitochondrial ultrastructure (p < 0.01), and decreased the enzymatic activity and protein expression of respiratory chain complexes (p < 0.05), leading to an inferior coupling efficiency (p < 0.05). As reflected by a decline in mitochondrial density (p < 0.01) and mitochondrial DNA copy number (p < 0.05), CORT reduced mitochondrial contents. Among all three PGC-1 family members, only PGC-1ß was down-regulated by CORT at the protein level (p < 0.05). Some aspects of these responses were tissue-specific and seemed to result from the depressed feed intake. Overall, CORT may impair mitochondrial biogenesis and oxidative phosphorylation in a PGC-1ß-dependent manner in chicken muscles.

Lipids associated with plant-bacteria interaction identified using a metabolomics approach in an Arabidopsis thaliana model.

Background: Systemic acquired resistance (SAR) protects plants against a wide variety of pathogens. In recent decades, numerous studies have focused on the induction of SAR, but its molecular mechanisms remain largely unknown. Methods: We used a metabolomics approach based on ultra-high-performance liquid chromatographic (UPLC) and mass spectrometric (MS) techniques to identify SAR-related lipid metabolites in an Arabidopsis thaliana model. Multiple statistical analyses were used to identify the differentially regulated metabolites. Results: Numerous lipids were implicated as potential factors in both plant basal resistance and SAR; these include species of phosphatidic acid (PA), monogalactosyldiacylglycerol (MGDG), phosphatidylcholine (PC), phosphatidylethanolamine (PE), and triacylglycerol (TG). Conclusions: Our findings indicate that lipids accumulated in both local and systemic leaves, while other lipids only accumulated in local leaves or in systemic leaves. PA (16:0_18:2), PE (34:5) and PE (16:0_18:2) had higher levels in both local leaves inoculated with Psm ES4326 or Psm avrRpm1 and systemic leaves of the plants locally infected with Psm avrRpm1 or Psm ES4326. PC (32:5) had high levels in leaves inoculated with Psm ES4326. Other differentially regulated metabolites, including PA (18:2_18:2), PA (16:0_18:3), PA (18:3_18:2), PE (16:0_18:3), PE (16:1_16:1), PE (34:4) and TGs showed higher levels in systemic leaves of the plants locally infected with Psm avrRpm1 or Psm ES4326. These findings will help direct future studies on the molecular mechanisms of SAR.

Role of melatonin in UV-B signaling pathway and UV-B stress resistance in Arabidopsis thaliana.

Melatonin (N-acetyl-5-methoxytryptamine) plays important roles in plant defences against a variety of biotic and abiotic stresses, including UV-B stress. Molecular mechanisms underlying functions of melatonin in plant UV-B responses are poorly understood. Here, we show that melatonin effect on molecular signalling pathways, physiological changes and UV-B stress resistance in Arabidopsis. Both exogenous and endogenous melatonin affected expression of UV-B signal transduction pathway genes. Experiments using UV-B signalling component mutants cop1-4 and hy5-215 revealed that melatonin not only acts as an antioxidant to promote UV-B stress resistance, but also regulates expression of several key components of UV-B signalling pathway, including ubiquitin-degrading enzyme (COP1), transcription factors (HY5, HYH) and RUP1/2. Our findings indicate that melatonin delays and subsequently enhances expression of COP1, HY5, HYH and RUP1/2, which act as central effectors in UV-B signalling pathway, thus regulating their effects on antioxidant systems to protect the plant from UV-B stress.

Effects of intraoperative individualized PEEP on postoperative atelectasis in obese patients: study protocol for a prospective randomized controlled trial.

BACKGROUND: Obese patients undergoing general anesthesia and mechanical ventilation during laparoscopic abdominal surgery commonly have a higher incidence of postoperative pulmonary complications (PPCs), due to factors such as decreasing oxygen reserve, declining functional residual capacity, and reducing lung compliance. Pulmonary atelectasis caused by pneumoperitoneum and mechanical ventilation is further aggravated in obese patients. Recent studies demonstrated that individualized positive end-expiratory pressure (iPEEP) was one of effective lung-protective ventilation strategies. However, there is still no exact method to determine the best iPEEP, especially for obese patients. Here, we will use the best static lung compliance (Cstat) method to determine iPEEP, compared with regular PEEP, by observing the atelectasis area measured by electrical impedance tomography (EIT), and try to prove a better iPEEP setting method for obese patients. METHODS: This study is a single-center, two-arm, prospective, randomized control trial. A total number of 80 obese patients with body mass index ≥ 32.5 kg/m2 scheduled for laparoscopic gastric volume reduction and at medium to high risk for PPCs will be enrolled. They will be randomly assigned to control group (PEEP5 group) and iPEEP group. A PEEP of 5 cmH2O will be used in PEEP5 group, whereas an individualized PEEP value determined by a Cstat-directed PEEP titration procedure will be applied in the iPEEP group. Standard lung-protective ventilation methods such as low tidal volumes (7 ml/kg, predicted body weight, PBW), a fraction of inspired oxygen ≥ 0.5, and recruitment maneuvers (RM) will be applied during and after operation in both groups. Primary endpoints will be postoperative atelectasis measured by chest electrical impedance tomography (EIT) and intraoperative oxygen index. Secondary endpoints will be serum IL-6, TNF-α, procalcitonin (PCT) kinetics during and after surgery, incidence of PPCs, organ dysfunction, length of in-hospital stay, and hospital expense. DISCUSSION: Although there are several studies about the effect of iPEEP titration on perioperative PPCs in obese patients recently, the iPEEP setting method they used was complex and was not always feasible in routine clinical practice. This trial will assess a possible simple method to determine individualized optimal PEEP in obese patients and try to demonstrate that individualized PEEP with lung-protective ventilation methods is necessary for obese patients undergoing general surgery. The results of this trial will support anesthesiologist a feasible Cstat-directed PEEP titration method during anesthesia for obese patients in attempt to prevent PPCs. TRIAL REGISTRATION: www.chictr.org.cn ChiCTR1900026466. Registered on 11 October 2019.

Constitutive expression of NtabSPL6-1 in tobacco and Arabidopsis could change the structure of leaves and promote the development of trichomes.

The coding sequence of NtabSPL6-1 was cloned by high-fidelity PCR with specific primers and was used in construction of a binary vector for overexpression. Wild-type Col-0 Arabidopsis plants and Qinyan95 tobacco leaves were transformed using floral dip and leaf disc methods, respectively. Phenotypic observation showed that constitutive expression of NtabSPL6-1 in Arabidopsis could promote the development of trichomes on leaf epidermis and influence the growth pattern of cauline leaves. In tobacco, ectopic expression of NtabSPL6-1 led to dwarfism of the plants and alteration of the leaf structure, accompanied by changes of the glandular trichomes in development. At the same time, the self-regulation capability of NtabSPL6-1 was determined by yeast two-hybrid system. The results indicated that SBP-C terminal domain and C terminal domain of NtabSPL6-1 possessed strong transcriptional activation ability; the intact protein, N terminal domain, and the first peptide fragment in N terminal domain possessed weak transcriptional activation ability; and the second and the third peptide fragments in N terminal domain had no transcriptional activation ability, suggesting the N terminal domain of NtabSPL6-1 could block the activity of the C terminal domain. NtabSPL6-1 may affect the resistance of plants to biotic stress factors indirectly by regulation of the trichome growth.

Efficient soluble deep blue electroluminescent dianthracenylphenylene emitters with CIE y (y ≤ 0.08) based on triplet-triplet annihilation.

It has been challenging to develop deep blue organic molecular fluorescent emitters with CIE y (y ≤ 0.08) based on triplet-triplet annihilation (TTA). Here, we report facilely available dianthracenylphenylene-based emitters, which have a 3,5-di(4-t-butylphenyl)phenyl moiety at the one end and 4-cyanophenyl or 3-pyridyl at the other end, respectively. Both fluorophores show a high glass transition temperature of over 220 °C with a thermal decomposition temperature of over 430 °C at an initial weight loss of 1%. The preliminary characterizations of the organic light-emitting diodes (OLEDs) that utilized these nondoped emitters provided high EQEs of 4.6%-5.9% with CIE coordinates (0.15, 0.07-0.08). The analysis of the EL transient decay revealed that TTA contributed to the observed performance. The results show that the new emitters are attractive as a potential TTA-based host to afford stable deep blue fluorescent OLEDs.

Ectopic expression of IiFUL isolated from Isatis indigotica could change the reproductive growth of Arabidopsis thaliana.

The coding sequence of IiFUL in Isatis indigotica was isolated and was used in transformation of Arabidopsis. IiFUL overexpressing Arabidopsis plants exhibited early flowering phenotype, accompanied with the reduction of flower number and the production of terminal flower on the top of the main stems. In development process, the flowers located on the top of the main stems generated a lot of variations in phenotype, including abnormal swelling of pistil, withering and numerical change of stamens and petals, appearance of stigmatoid tissues and naked ovules at the margin or inside of sepals. Besides, secondary flower could be formed within the flowers on the top of the main stems. These observations illustrated that IiFUL mainly affected the development of inflorescence meristems and pistils, but its ectopic expression could also disturb the normal growth of other floral organs. Moreover, the fertile siliques produced by the lateral inflorescences of IiFUL overexpressing Arabidopsis plants showed indehiscent phenotype, and the shape of the cauline leaves was changed significantly. The results of quantitative real-time PCR revealed that higher transcriptional levels of IiFUL could be detected in flowers and silicles of I. indigotica. In comprehensive consideration of the previous reports about the dehiscence phenotype of Arabidopsis siliques and the fact that the siliques of IiFUL overexpressing Arabidopsis plants were indehiscent in the present work, it can be speculated that high expression of IiFUL in pericarp is likely the reason why the silicles of I. indigotica possess an indehiscent phenotype.

Metabolomic analysis reveals the relationship between AZI1 and sugar signaling in systemic acquired resistance of Arabidopsis.

The function of AZI1 in systemic acquired resistance of Arabidopsis was confirmed by investigation of the phenotypic features of wild-type Col-0, AZI1 T-DNA knockout and AZI1 overexpressing plants after infection with virulent and avirulent Pseudomonas syringae. Real-time quantitative PCR and Northern blotting analyses showed that the transcript abundances of PR genes increased significantly in local and systemic leaves of wild-type Col-0 and AZI1 overexpressing plants challenged with avirulent P. syringae, whereas the mRNA accumulation of PR genes was obviously attenuated in local and systemic leaves of AZI1 T-DNA knockout plants after localized infiltration with avirulent Psm avrRpm1. The changes of metabolomic profiles in distal leaves of three types of materials infected with avirulent P. syringae were determined by (1)H NMR spectrometry and data mining showed that the soluble carbonhydrates might function as signal substances in the systemic immunity of Arabidopsis. At the same time, the expression of the sugar signaling genes in local and distal leaves after infection of avirulent P. syringae was compared. As a result, it was found that the transcript abundances of sugar signaling genes, including SUS1, SUS2, SUS3, SUS6, SUT1, HXK1, HXK2, SNRK1.2, ERD6, TPS1, TOR, SNRK1.1, SNRK1.3 and bZIP11, were obviously changed in distal leaves of different materials with the modulated AZI1 activities, indicating sugar-related genes are involved in regulation of the systemic immunity mediated by AZI1. These results also illustrated that the immune system associated with sugar molecules probably was an important part of the systemic acquired resistance in Arabidopsis.

Characterization and phylogenetic analysis of fifteen NtabSPL genes in Nicotiana tabacum L. cv. Qinyan95.

Fifteen SPL (SQUAMOSA PROMOTER BINDING PROTEIN-LIKE) genes were identified and characterized in Nicotiana tabacum L. cv. Qinyan95. The exon-intron structures of these genes were determined according to the coding sequences confirmed by RT-PCR and the genomic DNA sequences downloaded from the databases in Sol Genomics Network, and thirteen of them were found to carry the response element of miR156. To elucidate the origin of the validated NtabSPL genes, multiple alignments of the nucleotide sequences encompassing the open reading frames were conducted by using the orthologs in N. tabacum, Nicotiana sylvestris, Nicotiana tomentosiformis, and Nicotiana otophora. The results showed that six NtabSPL genes were derived from a progenitor of N. sylvestris, and nine NtabSPL genes were derived from a progenitor of N. tomentosiformis, further corroborating that N. tabacum came from the interspecific hybridization between the ancestors of N. sylvestris and N. tomentosiformis. In contrast to previous statements about highly repetitive sequences, the genome of N. tabacum mainly retained the paternal-derived SPL genes in diploidization process. Phylogenetic analyses based on the highly conserved SBP (SQUAMOSA PROMOTER BINDING PROTEIN) domains and the full-length amino acid sequences reveal that the SPL proteins of tobacco, tomato, and Arabidopsis can be categorized into eight groups. It is worth noting that N. tabacum contains seven NtabSPL6 genes originated from two parental genomes and NtabSPL6-2 possesses a GC-AG intron. In addition, transgenic tobacco plants harboring Arabidopsis Pri-miR156A were generated by Agrobacterium-mediated transformation method, and the constitutive expression of miR156 could obviously inhibit the activity of the NtabSPL genes containing its target site, suggesting the function of miR156 is conservative in tobacco and Arabidopsis.

CSDSymmetry: the definitive database of point-group and space-group symmetry relationships in small-molecule crystal structures.

An algorithm that perceives molecular symmetry has been applied to ca. 200,000 entries from the Cambridge Structural Database (CSD). For each molecule, the perceived point group, together with crystallographic properties such as space group, occupied Wyckoff positions and number of residues in the asymmetric unit, have been placed in a relational database, CSDSymmetry, using Microsoft Access software. Database queries can be constructed easily to find occurrences of any combination of molecular or crystallographic attributes, and thereby to answer questions on relative distributions. Some typical example queries are given. The inclusion of CSD reference codes enables direct visualization of search results using the Cambridge Crystallographic Data Centre's three-dimensional structure visualizer, Mercury.