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"Long, Dan"
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Copulatory mechanism and genital coupling of the longhorn beetle Moechotypa diphysis (Coleoptera, Cerambycidae)
The function of insect external genitalia has played a significant role in exploring insect mating mechanisms and male fertilization strategies. However, due to the privacy of genital coupling, insect copulatory mechanisms have only been investigated in a few insect groups. In this study, we observed the mating behavior using freeze-fixated pairs in copula to reveal the copulatory mechanism of the longhorn beetle Moechotypa diphysis (Pascoe, 1871). At the beginning stage of mating, the male M. diphysis usually takes 30 min to control the female and then extends its median lobe and endophallus. Approximately 80% of males (19/24) of M. diphysis exhibit multiple expansions (the membranous endophallus expands and enters into the female genital tract), ranging from two to five times. There are two types of expansions: short ones lasting for 1.4 to 49 s and long ones ranging from 1.03 to 7.23 min. During copulation, male tarsi continuously grasped the female elytra, thorax, and abdomen to help the male to initiate and maintain copulation. Male genital structures are closely connected to female genital structures: the apical phallomere and flagellum on the male endophallus contacting the bursa copulatrix duct and the spermathecal duct of the female, and the abundant microstructures on the surface of the everted male endophallus directly anchoring the female genital tract. Finally, we discuss the possible reasons for the evolution of their complex mating-related structures. Our research will help to explore the evolutionary mechanisms of insect genital structures.
Journal Article
Microglia sustain anterior cingulate cortex neuronal hyperactivity in nicotine-induced pain
Background
Long-term smoking is a risk factor for chronic pain, and chronic nicotine exposure induces pain-like effects in rodents. The anterior cingulate cortex (ACC) has been demonstrated to be associated with pain and substance abuse. This study aims to investigate whether ACC microglia are altered in response to chronic nicotine exposure and their interaction with ACC neurons and subsequent nicotine-induced allodynia in mice.
Methods
We utilized a mouse model that was fed nicotine water for 28 days. Brain slices of the ACC were collected for morphological analysis to evaluate the impacts of chronic nicotine on microglia. In vivo calcium imaging and whole-cell patch clamp were used to record the excitability of ACC glutamatergic neurons.
Results
Compared to the vehicle control, the branch endpoints and the length of ACC microglial processes decreased in nicotine-treated mice, coinciding with the hyperactivity of glutamatergic neurons in the ACC. Inhibition of ACC glutamatergic neurons alleviated nicotine-induced allodynia and reduced microglial activation. On the other hand, reactive microglia sustain ACC neuronal excitability in response to chronic nicotine, and pharmacological inhibition of microglia by minocycline or liposome-clodronate reduces nicotine-induced allodynia. The neuron-microglia interaction in chronic nicotine-induced allodynia is mediated by increased expression of neuronal CX3CL1, which activates microglia by acting on CX3CR1 receptors on microglial cells.
Conclusion
Together, these findings underlie a critical role of ACC microglia in the maintenance of ACC neuronal hyperactivity and resulting nociceptive hypersensitivity in chronic nicotine-treated mice.
Journal Article
The emerging role of neutrophil extracellular traps in ulcerative colitis
Ulcerative colitis (UC) is characterized by chronic non-recessive inflammation of the intestinal mucosa involving both innate and adaptive immune responses. Currently, new targeted therapies are urgently needed for UC, and neutrophil extracellular traps (NETs) are new therapeutic options. NETs are DNA-based networks released from neutrophils into the extracellular space after stimulation, in which a variety of granule proteins, proteolytic enzymes, antibacterial peptides, histones, and other network structures are embedded. With the deepening of the studies on NETs, their regulatory role in the development of autoimmune and autoinflammatory diseases has received extensive attention in recent years. Increasing evidence indicates that excess NETs exacerbate the inflammatory response in UC, disrupting the structure and function of the intestinal mucosal barrier and increasing the risk of thrombosis. Although NETs are usually assigned a deleterious role in promoting the pathological process of UC, they also appear to have a protective role in some models. Despite such progress, comprehensive reviews describing the therapeutic promise of NETs in UC remain limited. In this review, we discuss the latest evidence for the formation and degradation of NETs, focusing on their double-edged role in UC. Finally, the potential implications of NETs as therapeutic targets for UC will be discussed. This review aims to provide novel insights into the pathogenesis and therapeutic options for UC.
Journal Article
The efficacy of topological properties of functional brain networks in identifying major depressive disorder
Major Depressive Disorder (MDD) is a common mental disorder characterized by cognitive impairment, and its pathophysiology remains to be explored. In this study, we aimed to explore the efficacy of brain network topological properties (TPs) in identifying MDD patients, revealing variational brain regions with efficient TPs. Functional connectivity (FC) networks were constructed from resting-state functional magnetic resonance imaging (rs-fMRI). Small-worldness did not exhibit significant variations in MDD patients. Subsequently, two-sample t-tests were employed to screen FC and reconstruct the network. The discriminative ability of TPs between MDD patients and healthy controls was analyzed using receiver operating characteristic (ROC), ROC analysis showed the small-worldness of binary reconstructed FC network (
p
< 0.05) was reduced in MDD patients, with area under the curve (AUC) of local efficiency (Le) and clustering coefficient (Cp) as sample features having AUC of 0.6351 and 0.6347 respectively being optimal. The AUC of Le and Cp for retained brain regions by T-test (
p
< 0.05) were 0.6795 and 0.6956 respectively. Further, support vector machine (SVM) model assessed the effectiveness of TPs in identifying MDD patients, and it identified the Le and Cp in brain regions selected by the least absolute shrinkage and selection operator (LASSO), with average accuracy from leave-one-site-out cross-validation being 62.03% and 61.44%. Additionally, shapley additive explanations (SHAP) was employed to elucidate variations in TPs across brain regions, revealing that predominant variations among MDD patients occurred within the default mode network. These results reveal efficient TPs that can provide empirical evidence for utilizing nodal TPs as effective inputs for deep learning on graph structures, contributing to understanding the pathological mechanisms of MDD.
Journal Article
Natural products for the treatment of ulcerative colitis: focus on the JAK/STAT pathway
Ulcerative colitis (UC) is an autoimmune disease with an incompletely understood pathogenesis. The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway plays a key role in immune response and inflammation. More and more studies demonstrated that JAK/STAT signaling pathway is associated with the pathogenesis of UC. The JAK/STAT pathway affects UC in multiple ways by regulating intestinal inflammatory response, affecting intestinal mucosal barrier, modulating T cell homeostasis, and regulating macrophages. Encouragingly, natural products are promising candidates for the treatment of UC. Natural products have the advantage of being multi-targeted and rich in therapeutic modalities. This review summarized the research progress of JAK/STAT pathway-mediated UC. Furthermore, the latest studies on natural products targeting the JAK/STAT pathway for the treatment of UC were systematically summarized, including active ingredients such as arbutin, aloe polysaccharide, berberine, matrine, curcumin, Ginsenoside Rh2, and so on. The aim of this paper is to provide new ideas for drug development to regulate JAK/STAT signaling for treating UC.
Journal Article
Task scheduling of cloud computing using integrated particle swarm algorithm and ant colony algorithm
The optimization of task scheduling in cloud computing is built with the purpose of improving its working efficiency. Aiming at resolving the deficiencies during the method deployment, supporting algorithms are therefore introduced. This paper proposes a particle swarm optimization algorithm with the combination of based on ant colony optimization, which proposes the parameter determination into particle swarm algorithm. The integrated algorithm is capable of keeping particles in the fitness level at a certain concentration and guarantee the diversity of population. Further, the global best solution with high accurate converge can be exactly gained with the adjustment of learning factor. After the implementation of proposed method in task scheduling, the scheme for optimizing task scheduling shows better working performance in fitness, cost as well as running period, which presents a more reliable and efficient idea of optimal task scheduling.
Journal Article
Yersinia pestis can infect the Pawlowsky glands of human body lice and be transmitted by louse bite
Yersinia pestis , the causative agent of plague, is a highly lethal vector-borne pathogen responsible for killing large portions of Europe’s population during the Black Death of the Middle Ages. In the wild, Y . pestis cycles between fleas and rodents; occasionally spilling over into humans bitten by infectious fleas. For this reason, fleas and the rats harboring them have been considered the main epidemiological drivers of previous plague pandemics. Human ectoparasites, such as the body louse ( Pediculus humanus humanus ), have largely been discounted due to their reputation as inefficient vectors of plague bacilli. Using a membrane-feeder adapted strain of body lice, we show that the digestive tract of some body lice become chronically infected with Y . pestis at bacteremia as low as 1 × 10 5 CFU/ml, and these lice routinely defecate Y . pestis . At higher bacteremia (≥1 × 10 7 CFU/ml), a subset of the lice develop an infection within the Pawlowsky glands (PGs), a pair of putative accessory salivary glands in the louse head. Lice that developed PG infection transmitted Y . pestis more consistently than those with bacteria only in the digestive tract. These glands are thought to secrete lubricant onto the mouthparts, and we hypothesize that when infected, their secretions contaminate the mouthparts prior to feeding, resulting in bite-based transmission of Y . pestis . The body louse’s high level of susceptibility to infection by gram-negative bacteria and their potential to transmit plague bacilli by multiple mechanisms supports the hypothesis that they may have played a role in previous human plague pandemics and local outbreaks.
Journal Article
Critical levels and nitrogen fertilizer equivalencies for grain protein in winter wheat
Precision nitrogen (N) application methods have been developed for dryland wheat that utilize site‐specific measurements of grain protein concentration (GPC) to determine N fertilizer recommendations for the next season. The objectives of this study were to determine the critical protein level and N equivalent to a unit change in GPC from relationships between GPC, and grain yield or plant‐available N in soft white winter wheat (SWW, Triticum aestivum L.), and assess the consistency of these relationships across SWW cultivars grown under a wide range of precipitation. A 3‐year study was undertaken near two sites: Lexington (225 mm of mean annual precipitation) and Adams (450 mm) in Oregon. Differences in precipitation and N fertilization rates between sites were used to induce variability in grain yield and GPC of four cultivars. A critical protein concentration of 117.5 g kg−1 was defined by Cate–Nelson analysis of scatter plots of relative yield versus GPC. Critical protein among cultivars ranged between 105 and 118 g kg−1 suggesting that 117.5 g kg−1 might be used as a general indicator of N sufficiency. Slopes of the regression of available N on GPC were consistent across cultivars and revealed that 4.2–8.4 kg N ha−1 is equivalent to a unit change protein (1 g kg−1) in lower precipitation areas of the region where SWW is under water stress during grain filling. This information is useful in calculating the N to apply from the GPC in the previous season to meet crop requirements in the next season. Core Ideas A critical Grain protein level can indicate N sufficiency for yield of winter wheat under water stress. The N equivalent to a unit change in protein concentration is generalizable across winter wheat cultivars. Critical protein level and N equivalent to unit change in protein are useful for precision N management.
Journal Article