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BackgroundExtracellular vesicles (EVs) are regulators of cell-cell interactions and mediators of horizontal transfer of bioactive molecules between cells. EV-mediated cell-cell interactions play roles in physiological and pathophysiological processes, which maybe modulated by exposure to pathogens and cocaine use. However, the effect of pathogens and cocaine use on EV composition and function are not fully understood.ResultsHere, we used systems biology and multi-omics analysis to show that HIV infection (HIV +) and cocaine (COC) use (COC +) promote the release of semen-derived EVs (SEV) with dysregulated extracellular proteome (exProtein), miRNAome (exmiR), and exmiR networks. Integrating SEV proteome and miRNAome revealed a significant decrease in the enrichment of disease-associated, brain-enriched, and HIV-associated miR-128-3p (miR-128) in HIV + COC + SEV with a concomitant increase in miR-128 targets-PEAK1 and RND3/RhoE. Using two-dimensional-substrate single cell haptotaxis, we observed that in the presence of HIV + COC + SEV, contact guidance provided by the extracellular matrix (ECM, collagen type 1) network facilitated far-ranging haptotactic cues that guided monocytes over longer distances. Functionalizing SEV with a miR-128 mimic revealed that the strategic changes in monocyte haptotaxis are in large part the result of SEV-associated miR-128.ConclusionsWe propose that compositionally and functionally distinct HIV + COC + and HIV-COC- SEVs and their exmiR networks may provide cells relevant but divergent haptotactic guidance in the absence of chemotactic cues, under both physiological and pathophysiological conditions.

To implement standardized protective measures and to evaluate the safety and effectiveness of peripherally inserted central venous catheter (PICC) for severely and critically ill patients with COVID-19 in the isolation ward. PICC catheterization was performed to 9 patients who were diagnosed with COVID-19 and treated in the isolation ward. These patients were all given standardized protective measures during the PICC operation. The one-time success rate of catheterization was 100. 00%. There was no postoperative complications such as infection, bleeding, phlebitis, thrombosis, and no nosocomial infection occurred. The implementation of PICC catheterization in severely and critically ill patients in the isolation ward is safe and effective, and standardized protection in catheterization can effectively reduce the risk of cross-infection in hospital. (通过实施规范化防护措施, 评估经外周静脉置入中心静脉导管(PICC)在隔离病房收治的重型和危重型新型冠状病毒肺炎患者中应用的安全性和有效性。回顾隔离病房接受诊治的9例确诊/疑似患者的临床资料, 患者接受PICC置管术, 且术中实施规范化防护措施。9例患者均一次置管成功, 术后未发生感染、出血、静脉炎、血栓等并发症; 无一例置管患者和医务人员发生院内感染。隔离病房收治的重型和危重型新型冠状病毒肺炎患者中实施PICC置管安全、有效, 置管中规范化防护可以有效避免院内交叉感染的发生。)

Bacterial infections, especially those from drug‐resistant strains, pose a significant threat to healing diabetic skin injuries, with current treatments being intricated and often unsatisfactory. Inspired by octopuses, a biomimetic material using α‐cyclodextrin (α‐CD) and polyethylene glycol (PEG) assembled with graphene oxide end‐capped polyrotaxanes (GO‐PR) is developed, where α‐CD mimics the flexible tentacles of an octopus. Further, α‐CD is cationically modified with polyethyleneimine (PEI) to resemble octopus suction cups, creating GO‐PRP, which effectively captures and adheres to bacteria. Importantly, to emulate an octopus's ink defense, GO‐PRP is used as a carrier for nitric oxide (NO), resulting in GO‐PRP/NONOate. Utilizing the photothermal conversion of GO, near‐infrared light exposure triggers rapid heating and NO release, providing efficient antibacterial activity and biofilm dispersion, significantly reducing inflammation in diabetic skin injuries in type I rats. During wound healing, sustained NO release promotes vascular endothelial growth factor production and blood vessel regeneration, enhancing collagen formation and shortening the healing time for diabetic skin infections. Thus, octopus‐inspired GO‐PRP/NONOate emerges as a novel biomaterial for treating drug‐resistant bacterial infections in diabetic wounds in the biomedical field. [ABSTRACT FROM AUTHOR]

In the context of eccentric micro-scale Taylor–Couette flow, variations in localized flow scales result in a non-uniform fluid–solid interface slip state, distinct from the typically studied uniform slip velocity distribution. This study introduces a boundary condition definition method aimed at characterizing partial slip states, complemented by a coupled iterative analysis system tailored to address this complexity. Key contributions include the development of a method for calculating the limiting shear stress, which considers local velocity gradients and pressures. Validation demonstrates that the locally derived slip state aligns more closely with Knudsen number distributions of local flow scales compared to traditional uniform slip models, and exhibits greater consistency with experimentally measured pressure distributions. Additionally, the study reveals that eccentric Taylor–Couette flow, characterized by significant variations in local flow scales and strong self-induced pressure effects, leads to complex distributions of local pressure, velocity gradients, and differences in local slip velocities. Specifically, the non-uniform distribution of local pressure gradients due to eccentricity results in partial slip occurring predominantly on the rotor in regions with positive pressure gradients, and on the stator in regions with negative pressure gradients. Furthermore, the variation in gap height exerts a greater influence on local slip compared to rotational speed and eccentricity ratio. Under certain conditions influenced by pressure gradients, the slip velocity on the rotor may exceed its tangential speed. [ABSTRACT FROM AUTHOR]

Ovarian cancer is one of the most common gynecologic malignancies. Recurrence and metastasis often occur after treatment, and it has the highest mortality rate of all gynecological tumors. Cancer stem cells (CSCs) are a small population of cells with the ability of self-renewal, multidirectional differentiation, and infinite proliferation. They have been shown to play an important role in tumor growth, metastasis, drug resistance, and angiogenesis. Ovarian cancer side population (SP) cells, a type of CSC, have been shown to play roles in tumor formation, colony formation, xenograft tumor formation, ascites formation, and tumor metastasis. The rapid progression of tumor angiogenesis is necessary for tumor growth; however, many of the mechanisms driving this process are unclear as is the contribution of CSCs. The aim of this review was to document the current state of knowledge of the molecular mechanism of ovarian cancer stem cells (OCSCs) in regulating tumor angiogenesis. [ABSTRACT FROM AUTHOR]

Horizontal storage tanks are integral to the petrochemical industry but pose significant risks during earthquakes, potentially causing severe secondary disasters. Current seismic designs predominantly assume rigid tank walls, which can lead to an underestimation of seismic responses. This study introduces a novel analysis method for assessing the dynamic response of flexible-walled horizontal storage tanks. By separating the liquid velocity potential into convective and impulsive components and integrating these with beam vibration theory, we developed a simplified mechanical model. A parameter analysis and dynamic response research were conducted using numerical methods. Results indicate that flexible tank walls amplify seismic responses, including liquid dynamic pressure peaks, base shear, and overturning bending moments, compared to rigid walls. Additionally, the impact of flexible walls is more pronounced in tanks with larger radii, aspect ratios, diameter–thickness ratios, and H/R ratios. These findings highlight the necessity for revised seismic design approaches that consider wall flexibility to enhance the safety and resilience of horizontal storage tanks. [ABSTRACT FROM AUTHOR]

Gas foil bearings have been utilized in high-speed rotational machinery due to their superiority of load capacity and stability, which are closely associated with the shearing flow induced by variable sections in multiwedge clearance. This study focuses on the evolution pattern of vortices in Taylor–Couette flow with three-lobe multiwedge clearance using large-eddy simulation. As the Taylor number (Ta) increases, the shearing flow transitions from separation flow to Taylor vortex flow, followed by secondary transitions leading to wavy vortex flow. Separation vortices occur around the joint between two lobes, significantly delaying the first transition. Subsequently, Taylor vortices emerge and interact with the separation vortices, resulting in a complex evolution pattern of vortex series with increasing Ta. The presence of separation vortices promotes the formation of angular periodicity in Taylor vortices, accelerating the occurrence of angular periodicity stall and enhancing energy exchange between adjacent Taylor vortices. Taylor vortices are prone to breaking and merging. Additionally, Taylor vortices disrupt the shear layer of separation vortices between the stall region and the mid-radius separation region, leading to the migration of the shear layer and the singularity toward the mid-radius. Consequently, separation vortices move toward the mid-radius and transform from a one main vortex structure to two main vortex structures. Furthermore, spectral analysis of turbulent kinetic energy (TKE) reveals an inverse energy cascade characteristic with a slope of −7/3 at high frequencies, attributed to the TKE transmission between Taylor vortices and separation vortices. Both types of vortices exhibit intermittent and periodic behavior. [ABSTRACT FROM AUTHOR]