A parabrachial to hypothalamic pathway mediates defensive behavior.

Defensive behaviors are critical for animal's survival. Both the paraventricular nucleus of the hypothalamus (PVN) and the parabrachial nucleus (PBN) have been shown to be involved in defensive behaviors. However, whether there are direct connections between them to mediate defensive behaviors remains unclear. Here, by retrograde and anterograde tracing, we uncover that cholecystokinin (CCK)-expressing neurons in the lateral PBN (LPBCCK) directly project to the PVN. By in vivo fiber photometry recording, we find that LPBCCK neurons actively respond to various threat stimuli. Selective photoactivation of LPBCCK neurons promotes aversion and defensive behaviors. Conversely, photoinhibition of LPBCCK neurons attenuates rat or looming stimuli-induced flight responses. Optogenetic activation of LPBCCK axon terminals within the PVN or PVN glutamatergic neurons promotes defensive behaviors. Whereas chemogenetic and pharmacological inhibition of local PVN neurons prevent LPBCCK-PVN pathway activation-driven flight responses. These data suggest that LPBCCK neurons recruit downstream PVN neurons to actively engage in flight responses. Our study identifies a previously unrecognized role for the LPBCCK-PVN pathway in controlling defensive behaviors.

Neural circuit control of innate behaviors.

All animals possess a plethora of innate behaviors that do not require extensive learning and are fundamental for their survival and propagation. With the advent of newly-developed techniques such as viral tracing and optogenetic and chemogenetic tools, recent studies are gradually unraveling neural circuits underlying different innate behaviors. Here, we summarize current development in our understanding of the neural circuits controlling predation, feeding, male-typical mating, and urination, highlighting the role of genetically defined neurons and their connections in sensory triggering, sensory to motor/motivation transformation, motor/motivation encoding during these different behaviors. Along the way, we discuss possible mechanisms underlying binge-eating disorder and the pro-social effects of the neuropeptide oxytocin, elucidating the clinical relevance of studying neural circuits underlying essential innate functions. Finally, we discuss some exciting brain structures recurrently appearing in the regulation of different behaviors, which suggests both divergence and convergence in the neural encoding of specific innate behaviors. Going forward, we emphasize the importance of multi-angle and cross-species dissections in delineating neural circuits that control innate behaviors.

Protocol for targeting the magnocellular neuroendocrine cell ensemble via retrograde tracing from the posterior pituitary.

The hypothalamic magnocellular neuroendocrine cells (MNCs) project to the posterior pituitary (PPi), regulating reproduction and fluid homeostasis. It has been challenging to selectively label and manipulate MNCs, as they are intermingled with parvocellular neuroendocrine cells projecting to the median eminence. Here, we provide a step-by-step protocol for specifically targeting the MNCs by infusing retrograde viral tracers into the PPi. When combined with optogenetics, chemogenetics, and transgenic animals, this approach allows cell-type-specific manipulation of MNCs in multiple sites for functional dissection. For complete details on the use and execution of this protocol, please refer to Zhang et al. (2021) and Tang et al. (2020).

Functional Outcome and Inflammatory Response of Patients with Extra-Articular Distal Humeral Fractures following Implantation of Anatomically Precontoured Locking Compression Plates through a Posterior Approach.

Distal humeral fractures are challenging injuries to surgically correct and account for up to 2% of all adult fractures. Surgical management of extra-articular distal humeral fractures is challenging considering surgical approach, implant selection, and position of the implant owing to the availability of different precontoured implants and plate configurations. Anatomically precontoured locking compression plates (APLCPs) allow the placement of angular stable screws right underneath the reduced joint surface fragments. To date, there is a lack of evidence supporting its superiority to conventional locking plate osteosynthesis (LPO) in treating extra-articular distal humeral fractures. The objective of the study is to evaluate the efficacy and safety of APLCPs in the treatment of extra-articular distal humeral fractures. A total of 100 patients diagnosed with humeral fractures and receiving treatments in our hospital between May 2018 and May 2020 fulfilled inclusion and exclusion criteria and were randomly assigned to LPO and APLCP groups according to the odd-even of the order of hospital admission, 50 cases per groups. Clinical endpoints were assessed including operation time; in-bed time; length of hospital stay; volume of intraoperative blood loss; VSA scores before and 24, 48, and 72 h after surgery; MEPS scores before and 3, 6, and 12 months after surgery; range of motion, flexion, and extension of the elbow; serum levels of CK, CRP, and IL-6; and incidence of complications after surgery. It was found that the APLCP group exhibited shortened operation time and in-bed time, decreased length of hospital stay, and reduced volume of intraoperative blood loss compared to the LPO group (all P < 0.001). The two groups had declined VSA scores concomitant with increased MEPS scores after surgery in a time-dependent manner (P < 0.001). Notably, the VSA scores in the APLCP group were all lower than those in the LPO group at indicated time points (24, 48, and 72 h) after surgery (P < 0.001). Besides, the MEPS scores in the APLCP group were all higher than those in the LPO group at indicated time points (3, 6, and 12 months) after surgery (P < 0.001). It was revealed that the patients receiving extra-articular distal humeral APLCP through posterior approaches exhibited greater ranges of motion, flexion, and extension of the elbow than those receiving LPO after surgery (P < 0.001). The patients receiving extra-articular distal humeral APLCP through posterior approaches exhibited lower serum levels of IL-6, CRP, and CK than those receiving LPO after surgery (IL-6: P=0.007, CRP: P=0.001, CK: P=0.001). The APLCP had a lower total incidence rate of complication than the LPO group (48.00% vs. 18.00%, P=0.003). In conclusion, these data support the notion that the implantation of anatomically precontoured APLCP through a posterior approach allows for improved functional outcomes and attenuated inflammatory response and prevents the incidence of postoperative complications compared to conventional LPO for internal fixation of extra-articular distal humeral fractures.

Bioinformatic analysis and experimental identification of blood biomarkers for chronic nonunion.

BACKGROUND: Incomplete fracture healing may lead to chronic nonunion; thus, determining fracture healing is the primary issue in the clinical treatment. However, there are no validated early diagnostic biomarkers for assessing chronic nonunion. In this study, bioinformatics analysis combined with an experimental verification strategy was used to identify blood biomarkers for chronic nonunion. METHODS: First, differentially expressed genes in chronic nonunion were identified by microarray data analysis. Second, Dipsaci Radix (DR), a traditional Chinese medicine for fracture treatment, was used to screen the drug target genes. Third, the drug-disease network was determined, and biomarker genes were obtained. Finally, the potential blood biomarkers were verified by ELISA and qPCR methods. RESULTS: Fifty-five patients with open long bone fractures (39 healed and 16 nonunion) were enrolled in this study, and urgent surgical debridement and the severity of soft tissue injury had a significant effect on the prognosis of fracture. After the systems pharmacology analysis, six genes, including QPCT, CA1, LDHB, MMP9, UGCG, and HCAR2, were chosen for experimental validation. We found that all six genes in peripheral blood mononuclear cells (PBMCs) and serum were differentially expressed after injury, and five genes (QPCT, CA1, MMP9, UGCG, and HCAR2) were significantly lower in nonunion patients. Further, CA1, MMP9, and QPCT were markedly increased after DR treatment. CONCLUSION: CA1, MMP9, and QPCT are biomarkers of nonunion patients and DR treatment targets. However, HCAR2 and UGCG are biomarkers of nonunion patients but not DR treatment targets. Therefore, our findings may provide valuable information for nonunion diagnosis and DR treatment. TRIAL REGISTRATION: ISRCTN, ISRCTN13271153. Registered 05 April 2020-Retrospectively registered.

BZR1 Family Transcription Factors Function Redundantly and Indispensably in BR Signaling but Exhibit BRI1-Independent Function in Regulating Anther Development in Arabidopsis.

BRASSINAZOLE-RESISTANT 1 family proteins (BZRs) are central transcription factors that govern brassinosteroid (BR)-regulated gene expression and plant growth. However, it is unclear whether there exists a BZR-independent pathway that mediates BR signaling. In this study, we found that disruption of all BZRs in Arabidopsis generated a hextuple mutant (bzr-h) displaying vegetative growth phenotypes that were almost identical to those of the null mutant of three BR receptors, bri1brl1brl3 (bri-t). By RNA sequencing, we found that global gene expression in bzr-h was unaffected by 2 h of BR treatment. The anthers of bzr-h plants were loculeless, but a similar phenotype was not observed in bri-t, suggesting that BZRs have a BR signaling-independent regulatory role in anther development. By real-time PCR and in situ hybridization, we found that the expression of SPOROCYTELESS (SPL), which encodes a transcription factor essential for anther locule development, was barely detectable in bzr-h, suggesting that BZRs regulate locule development by affecting SPL expression. Our findings reveal that BZRs are indispensable transcription factors required for both BR signaling and anther locule development, providing new insight into the molecular mechanisms underlying the microsporogenesis in Arabidopsis.

Identification of early responsive genes in human amnion epithelial FL cells induced by N-methyl-N'-nitro-N-nitrosoguanidine using oligonucleotide microarray and quantitative real-time RT-PCR approaches.

The alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) induces cellular DNA damage and other comprehensive alterations that lead to chromosomal aberrations, mutations, tumor initiation, and cell death. However, the molecular mechanism of MNNG-induced cellular stress remains unclear. We undertook a genome-wide analysis of early transcriptional responses of human FL amnion epithelial cells to three relatively low doses of MNNG (0.2, 1.0, and 10.0 microM). Using Affymetrix GeneChip HG-U133 Set oligonucleotide microarrays, a total of 281 genes were found to change their expression after exposure to all three doses of MNNG compared with the vehicle control, DMSO. Of these, 70, 112, and 146 genes showed different expression levels following treatment with low, medium, and high-dose MNNG, respectively. A subset of these genes were selected for further confirmation using quantitative real-time RT-PCR with ABI TaqMan((R)) low-density arrays, and the differential expression of 33 genes was validated. The results demonstrate that low doses of MNNG can induce various changes in gene expression at an early stage of exposure. The responsive genes are involved in multiple cellular biological processes including transcription regulation, signal transduction, cell cycle regulation, cytoskeleton organization, protein synthesis, immune responses, and metabolism. The cell cycle progression was down-regulated, in which several genes were validated involved, including the cell cycle regulators (CDK6, STK6, CENPA, and CCNF), the transcription factor ID-1, and the calcium signaling molecules (CAMK2G and NFAT5). The possible roles of the responsive genes and their related pathways in MNNG-induced cellular responses are discussed. This study helps to complete the picture of how cells respond to environmental chemical exposure via transcriptional regulation.

Zinc finger proteins and other transcription regulators as response proteins in benzo[a]pyrene exposed cells.

Proteomic analysis, which combines two-dimensional electrophoresis (2-DE) and mass spectrometry (MS), is an important approach to screen proteins responsive to specific stimuli. Benzo[a]pyrene (B[a]P), a prototype of polycyclic hydrocarbons (PAHs), is a potent procarcinogen generated from the combustion of fossil fuel and cigarette smoke. To further probe the molecular mechanism of mutagenesis and carcinogenesis, and to find potential molecular markers involved in cellular responses to B[a]P exposure, we performed proteomic analysis of whole cellular proteins in human amnion epithelial cells after B[a]P-treatment. Image visualization and statistical analysis indicated that more than 40 proteins showed significant changes following B[a]P-treatment (P < 0.05). Among them, 20 proteins existed only in the control groups, while six were only present in B[a]P-treated cells. In addition, the expression of 10 proteins increased whereas 11 decreased after B[a]P-treatment. These proteins were subjected to in-gel tryptic digestion followed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) analysis. Using peptide mass fingerprinting (PMF) to search the nrNCBI database, we identified 22 proteins. Most of these proteins have unknown functions and have not been previously connected to a response to B[a]P exposure. To further annotate the characteristics of these proteins, GOblet analysis was carried out and results indicated that they were involved in multiple biological processes including regulation of transcription, cell proliferation, cell aging and other processes. However, expression changes were noted in a number of transcription regulators, including eight zinc finger proteins as well as SNF2L1 (SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 1), which is closely linked to the chromatin remodeling process. These data may provide new clues to further understand the implication of these proteins in cellular responses to carcinogen exposure as well as the molecular mechanisms of B[a]P-induced mutagenesis and carcinogenesis.