Elasto-inertial particle focusing in sinusoidal microfluidic channels.

Dean flow existing in sinusoidal channels could enhance the throughput and efficiency for elasto-inertial particle focusing. However, the fundamental mechanisms of elasto-inertial focusing in sinusoidal channels are still unclear. This work employs four microfluidic devices with symmetric and asymmetric sinusoidal channels to explore the elasto-inertial focusing mechanisms over a wide range of flow rates. The effects of rheological property, flow rate, sinusoidal channel curvature, particle size, and asymmetric geometry on particle focusing performance are investigated. It is intriguing to find that the Dean flow makes a substantial contribution to the particle elasto-inertial focusing. The results illustrate that a better particle focusing performance and a faster focusing process are obtained in the sinusoidal channel with a small curvature radius due to stronger Dean flow. In addition, the particle focusing performance is also related to particle diameter and rheological properties, the larger particles show a better focusing performance than smaller particles, and the smaller flow rate is required for particles to achieve stable focusing at the outlet in the higher concentration of polyvinylpyrrolidone solutions. Our work offers an increased knowledge of the mechanisms of elasto-inertial focusing in sinusoidal channels. Ultimately, these results provide supportive guidelines into the design and development of sinusoidal elasto-inertial microfluidic devices for high-performance focusing.

Particle focusing mechanisms in λ-DNA solution flowing in a straight microchannel.

Most biological fluids (such as blood, saliva, and lymph) in nature have certain viscoelasticity and are beginning to be used as the carrying fluids for viscoelastic microfluidics. However, the particle-focusing mechanisms in these new biological viscoelastic fluids are still unclear. In this work, the particle-focusing mechanisms in λ-DNA solutions were systematically explored. We first explored the particle focusing dynamics in a square cross-section under varied flow rates to uncover the effects of flow rate on particle focusing. Three focusing stages, from the classic five-position viscoelastic focusing to single-stream focusing and finally to multiplex-stream focusing, were clearly demonstrated. In addition, the particle focusing process along the channel length was demonstrated, and a first-fast-and-then-slow focusing process was clearly observed. Then, the effects of λ-DNA concentrations on particle focusing were explored and compared using the solutions with 0-25 ppm λ-DNA. Finally, we discussed the inferences of blockage ratio on particle focusing by changing the particle diameter and cross-sectional dimensions. Our work may provide a deeper understanding on the particle focusing mechanisms in biological viscoelastic fluids and lays a foundation for the subsequent particle counting and analysis and the development of low-cost portable flow cytometers.

Nalbuphine 20 mg combined with sufentanil 2 µg/kg exerts a better postoperative analgesia effect in patients undergoing a second cesarean section: a randomised trial.

BACKGROUND: Pain management following cesarean section remains a challenge, with many puerpera suffering from severe acute postoperative pain. And for a second cesarean section the degree of uterine contraction pain is more severe and frequent than that of a primipara. This study investigated the effect of different doses of nalbuphine combined with sufentanil for postoperative analgesia in patients undergoing a second cesarean section. METHODS: We prospectively recruited 168 women with a scarred uterus undergoing elective second cesarean section and they were randomly divided into 4 groups by random number extraction. A single intravenous injection of different doses of nalbuphine was given before the intravenous drip of oxytocin, and visual analogue scale (VAS) scores of uterine contraction pain were recorded 10 minutes before intravenous infusion of oxytocin (T1) and 10 minutes (T2), 30 minutes (T3), and 60 minutes (T4) after intravenous infusion of oxytocin. At 4, 8, 12, 24, and 48 hours after patient-controlled intravenous analgesia (PCIA), pain intensity was reassessed using the VAS score. RESULTS: One hundred and sixty patients underwent elective second cesarean section in between December 2020 and May 2021 completed the study. The VAS scores of uterine contractions at T1 and T4 were 3 (1.0), while the VAS scores at T2 and T3 were 7 (1.0), 6 (1.0), 5 (1.0), 5 (1.0) and 8 (1.0), 5 (2.0), 3 (1.0), 3 (0.75). The VAS scores at 12 hours after surgery of nalbuphine10mg and sufentanil (NS1), nalbuphine 10 mg and sufentanil 20 mg (NS2) and nalbuphine 30 mg and sufentanil 20 mg (NS3) were lower than sufentanil (S) group (P<0.001). Compared with the S group, total amount of sufentanil and PCIA compression numbers in the NS1, NS2, and NS3 groups at 4-8 and 8-12 hours after surgery decreased (P<0.001), with a more significant decrease in the NS2 and NS3 groups than in the NS1 group (P<0.001). The NS3 group had a significantly higher incidence of dizziness and sleepiness (P=0.02, P=0.001). Compared with the NS2 and NS3 groups, the incidence of respiratory depression in the S group was significantly higher (P=0.001). CONCLUSIONS: A single intravenous injection of nalbuphine 20 mg 10 minutes before the infusion of oxytocin combined with sufentanil 2 µg/kg could be safely used for postoperative analgesia in patients undergoing a second cesarean section and could effectively inhibit uterine contractions induced by oxytocin and reduce adverse reactions. TRIAL REGISTRATION: Clinical Trial Registry ChiCTR2100042382.

Development and validation of prognostic models for colon adenocarcinoma based on combined immune-and metabolism-related genes.

Background: The heterogeneity of tumor tissue is one of the reasons for the poor effect of tumor treatment, which is mainly affected by the tumor immune microenvironment and metabolic reprogramming. But more research is needed to find out how the tumor microenvironment (TME) and metabolic features of colon adenocarcinoma (COAD) are related. Methods: We obtained the transcriptomic and clinical data information of COAD patients from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Consensus clustering analysis was used to identify different molecular subtypes, identify differentially expressed genes (DEGs) associated with immune-and metabolism-related genes (IMRGs) prognosis. Univariate and multivariable Cox regression analysis and Lasso regression analysis were applied to construct the prognostic models based on the IMRG risk score. The correlations between risk scores and TME, immune cell infiltration, and immune checkpoint genes were investigated. Lastly, potential appropriate drugs related to the risk score were screened by drug sensitivity analysis. Results: By consensus clustering analysis, we identified two distinct molecular subtypes. It was also found that the multilayered IMRG subtypes were associated with the patient's clinicopathological characteristics, prognosis, and TME cell infiltration characteristics. Meanwhile, a prognostic model based on the risk score of IMRGs was constructed and its predictive power was verified internally and externally. Clinicopathological analysis and nomogram give it better clinical guidance. The IMRG risk score plays a key role in immune microenvironment infiltration. Patients in the high-risk groups of microsatellite instability (MSI) and tumor mutational burden (TMB) were found to, although with poor prognosis, actively respond to immunotherapy. Furthermore, IMRG risk scores were significantly associated with immune checkpoint gene expression. The potential drug sensitivity study helps come up with and choose a chemotherapy treatment plan. Conclusion: Our comprehensive analysis of IMRG signatures revealed a broad range of regulatory mechanisms affecting the tumor immune microenvironment (TIME), immune landscape, clinicopathological features, and prognosis. And to explore the potential drugs for immunotherapy. It will help to better understand the molecular mechanisms of COAD and provide new directions for disease treatment.

The impact of tubeless anesthesia versus intubated anesthesia on cerebral oxygen saturation and postoperative cognitive function in patients undergoing video-assisted thoracoscopic surgery: a randomized trial.

Background: In video-assisted thoracoscopic surgery (VATS), intubated anesthesia may affect cerebral oxygen balance and postoperative cognitive dysfunction (POCD). To avoid complications associated with intubated anesthesia, tubeless strategies have been proposed in recent years, but its effect on cerebral oxygen balance and POCD is still unclear. This prospective study compared the cerebral oxygen saturation and the incidence of POCD in patients undergoing VATS anesthetized with tubeless anesthesia vs. intubated anesthesia. Methods: A total of 60 patients with American Society of Anesthesiologists Standard (ASA) grade I-II who planned to undergo VATS at The First People's Hospital of Yunnan Province between May and October 2021 were selected and divided into non-intubated spontaneous ventilation group (SV group) or intubated mechanical ventilation group (MV group) by random number method. The primary outcome included the incidence of POCD and Mini-Mental State Examination (MMSE) on the 1st before operation and the 4th, 7th, 14th, and 30th day postoperatively, and cerebral oxygen saturation during surgery. Other outcomes of interest include respiratory and hemodynamic parameters, serum concentration of cognitive function related proteins [S100ß, interleukin (IL)-6, IL-1ß, and tumor necrosis factor α (TNF-α)], inflammatory cell counts, perioperative adverse events (arrhythmia, hypoxemia, asphyxia, etc.), postoperative pain scores, etc. Results: The incidence of hypercapnia in the SV group was significantly higher than in the MV group (P<0.001). Cerebral oxygen saturation at intraoperative was significantly higher than that in MV group (P<0.01). There was no significant difference in the incidence of POCD and the expression of cognitive function related proteins between the two groups (P>0.05). Leukocyte and neutrophil counts were significantly higher in the MV group after operation (P<0.05), whilst compared to the MV group, the SV group showed shorter postoperative recovery time, rest time before the first out of bed activity, chest tube duration, as well as less drainage volume of the chest tube and postoperative sore throat rarely occurred (P<0.05). Conclusions: Tubeless VATS can increase the incidence of hypercapnia and intraoperative cerebral oxygen saturation, but has no statistically significant difference in the incidence of POCD. In addition, tubeless anesthesia reduces systemic inflammatory, promotes the early postoperative mobilization, and accelerates the postoperative rehabilitation of patients. Trial Registration: Chinese Clinical Trial Registry ChiCTR2100042381.

Kaempferia parviflora and Its Methoxyflavones: Chemistry and Biological Activities.

Kaempferia parviflora (KP), a health-promoting herb, has been traditionally used for treating a variety of diseases. Pharmacological studies have claimed the various benefits from KP and its main effective methoxyflavones, including cellular metabolism-regulating activity, anticancer activity, vascular relaxation and cardioprotective activity, sexual enhancing activity, neuroprotective activity, antiallergic, anti-inflammatory, and antioxidative activity, antiosteoarthritis activity, antimicroorganism activity, and transdermal permeable activity. These might be associated with increased mitochondrial functions and activated cGMP-NO signaling pathway. However, the underlying molecular mechanisms of KP and its methoxyflavones are still under investigation. The clinical applications of KP and its methoxyflavones may be limited due to their low bioavailability. But promising strategies are on the way. This review will comprehensively discuss the biological activities of KP and its methoxyflavones.

Spinal TRPC6 channels contributes to morphine-induced antinociceptive tolerance and hyperalgesia in rats.

The chronic administration of opioids results in the development of morphine analgesic tolerance and withdrawl-induced hyperalgesia, which limits their clinical utility in pain treatment. However, the cellular mechanisms underlying opioid-induced tolerance and hyperalgesia are not fully understood. The transient receptor potential canonical channel TRPC6 is important for brain development and function, as it regulates cytosolic, endoplasmic reticulum, and mitochondrial Ca2+ levels in neural cells. Here, we report that TRPC6 expression in the spinal cord was up-regulated after chronic morphine treatment. Furthermore, inhibition of TRPC6 in the spinal cord blocked the induction of morphine tolerance and hyperalgesia without affecting basal pain perception. These effects were attributed to the attenuation of morphine-induced neuroimmune activation and increased levels of CaMKIIα and nNOS in the spinal cord. This data suggests that specific TRPC6 inhibitors could be utilized for the prevention of morphine-induced antinociceptive tolerance and hyperalgesia in chronic pain management.

Complement factor C5a and C5a receptor contribute to morphine tolerance and withdrawal-induced hyperalgesia in rats.

Morphine is a potent opioid analgesic. However, the repeated use of morphine causes tolerance and hyperalgesia. Neuroinflammation has been reported to be involved in morphine tolerance and withdrawal-induced hyperalgesia. The complement system is a crucial effector mechanism of immune responses. The present study investigated the roles of complement factor C5a and C5a receptor (C5aR) in the development of morphine tolerance and withdrawal-induced hyperalgesia. In the present study, the levels of C5a and C5aR were increased in the L5 lumbar spinal cords of morphine-tolerant rats. The administration of C5a promoted the development of hyperalgesia and the expression of spinal antinociceptive tolerance to intrathecal morphine in both mechanical and thermal test. However, these phenomena caused by morphine were significantly attenuated by the C5aR antagonist PMX53. These results suggest that complement activation within the spinal cord is involved in morphine tolerance and withdrawal-induced hyperalgesia. C5a and C5aR may serve as novel targets for the control of morphine tolerance and withdrawal-induced hyperalgesia.